Loading...
HomeMy WebLinkAboutDRC-2011-001089 - 0901a068801f2e25-2011-00 4 Received JAN 2011 'i^ (5 ro o Division of is",' V Radiation Conirol -v/ o.. A' / "•'J'r'-: 'iK^X . Denison Mines (USA)Corpr 1050 17th Street, Suite 950 Denver, CO 80265 USA Tel: 303 628-7798 Fax : 303 389-4125 www.denisonmines.com DENISO MINES January 10, 2011 VIA E-MAIL AND OVERNIGHT DELIVERY Mr. Rusty Lundberg Utah Department of Environmental Quaiity 195 North 1950 West P.O. Box 144810 Salt Lake City, UT 84114-4820 Re: State of Utah Ground Water Discharge Permit ("GWDP") No. UGW370004 Transmittal of Revised Documents Addressing White Mesa Uranium Mill New Cell 4B and Response to Division of Radiation Control ("DRC") Letter of January 6, 2011 Regarding Comprehensive Comments on Proposed Revised Plans Dear Mr. Lundberg; This letter transmits Denison Mines (USA) Corp's proposed revisions to the Tailings Management System and Discharge Minimization Technology Monitoring ("DMT") Plan, and the Best Available Technology Operations and Maintenance ("BAT O&M") Plan for the White Mesa Mill which are currently pending UDEQ approval. This letter also responds to DRC's letter of January 6, 2011 requesting additional changes to previously submitted versions of these "documents. Per DRC's letter, we understand that the Contingency Plan will be addressed separately and changes will not be tied to approval for use of Cell 4B or the New Decontamination Pad. DRC received the October 11, 2010 letter requesting changes to previously submitted versions of the DMT Plan BAT O&M Plan, and Contingency Plan. To address those comments and other changes necessary for operation of Cell 4B, Denison submitted on November 12, 2010 redline and clean copy revisions of those documents entitled DMT Plan Revision 11, BAT Q&M Plan Revision 2.0 and Contingency Plan Revision 4.0. DRC reviewed those submittals and requested additional changes to the DMT and BAT Q&M Plans in the letter of January 6, 2011. Denison has accepted all the changes submitted on November 12, 2010 to.create new black-line copies of the DMT and BAT Q&M Plans, and has prepared the additional changes, in response to DRC's January 6, 2011 letter, as redlined markups, entitled DMT Plan 11.1 and BAT Q&M Plan Revision 2.1, These revisions have been provided, respectively, as Attachments 1 and 2 to this letter. For ease of review, both of the revised documents have also been provided as clean file versions with all changes accepted. Denison requests that UDEQ review and approve the versions attached to this letter, which consolidate into one set of documents all changes submitted by Denison since September 2008, for which Denison is awaiting DRC approval. N:\Cell 4B\January 2011 Submittals and Revisions for Cell 4B\01.10.11 Transmittal to DRC Plan Revisions for Cell 4B.doc Letter to Mr. Rusty Lundberg January 12, 2011 Page 2 We have also provided, below, specific responses to each request in UDEQ's January 6, 2011 letter. The sections and numbering of the remainder of this letter follow the DRC January 6, 2011 letter. Each UDEQ request is shown in italics, below, followed by Denison's response. DEQ Comments and Responses The Continqencv Plan (11/2010 Revision: DUSA-4) Please be aware that in order to expedite the Cell 4B review process, that DRC review of the Contingency Plan will be addressed under separate cover, proceed independently, and not be tied to the use of the NDP nor Cell 4B. The following is noted for future reference: A. In the subject November 12, 2010 letter, DUSA provides proposed red-line and clean versions ofthe Contingency Plan version noted, which include aspects regarding Cell 4B. B. The third paragraph as well as Section 2 .a.1 of a September2,2010 DUSA letter discusses contingency plan comments in our May 10,2010 letter Denison Response: No response required. The DMT Plan (11/2010 Revision: DUSA-11 1. We acknowledge a section of paragraph 3 . l.e.i.D has been changed appropriately to read that, ". . . The depth to water from the top . . . of any of the three (3) observation ports to the standing water shall be no less than 6.2 feet." It appears that incorporation of this item into an approved DMT Plan would complete the issues regarding the NDP with respect to DMT Plan adjustments. Denison Response: No response required. 2. The DMT Plan (as well as the O&M Plan), incorporating necessary items for Cell 4B, must be approved prior to DRC authorization of use for Cell4B. Regarding freeboard requirements, the Plans proposed by the subject DUSA November 12, 2010 letter make the assumption that Cell 4B is currently authorized for use, and it is not necessary to establish a freeboard for Cell 4, A. However, this is incorrect. This. approach DUSA has taken appears to necessitate one of the following: a. That the last action prior to authorizing use of Cell 4B must be the approval ofthe DMT Plan (and the O&M Plan), or b. To obtain approval of the DMT and O&M Plans now, DUSA change the plans to establish the freeboard for Cell 4A. to be one of the following, either (1) . The fixed freeboard elevation for Cell 4A, established by the DRC freeboard variance letter of November 20, 2008, or (2) . Change the current freeboard determination verbiage proposed in these Plans be more robust This would include that the freeboard for Cell 4A or Cell 4B, as may be applicable, would be established by the rigorous freeboard calculation method outlined in former proposed Plans, but would be written such that if Cell 4B becomes approved, that the freeboard determination method would no longer be needed for or apply to Cell 4A. Please provide DRC your decision to us in this regard, together with any and all necessary corresponding changes to the DMT Plan. DENISO MINES Letter to Mr. Rusty Lundberg January 12, 2011 Pages Denison Response: Denison has chosen option (a.) above and will request the approval of the DMT Plan and the Q&M Plan as the last action prior to the UDEQ authorization for the use of Cell 4B. As such, the changes requested regarding the reintroduction of Freeboard limits for Cell 4A are not necessary. 3. The following changes in DMT Plan forms, related to tailings beach elevations, are needed due to the need to measure beach elevations in tailings Cells 4A or 4B, as applicable ( per paragraph 2 above). This issue was brought to your attention eadierin our letter dated October 11, 2010. The freeboard for these ponds is determined from the use of such (see paragraph 6.3 and Appendix F ofthe DMT Plan): a. On page 28 of 49 in Appendix A of the submitted clean copy of the Plan: (1) The heading numbered as one, near the left margin on that page; must state "Pond and Beach elevations . . . ,"the following earlier proposed DMT Plan versions also contained this provision; (a) . 12/08 Revision: Denison-7, (b) . 05/09 Revision: Denison-8, and (c) . 3/10 Revision:Denison-9. (2) In the corresponding page of the submitted red-line version (i. e. page 33 of 56), item number one contains sections for Cell 4A. and Cell 48. An item (d) stating "Elevation of Beach Area with the Highest Elevation (monthly)," must be added into the sections on this page for each of these cells, as applicable with paragraph 2 above. (Earlier proposed DMT Plan versions contain this item (d) for Cell 4A, in the versions given in paragraph 3.a. above). b. Section 3.1.d.vii, paragraph C should be labeled as paragraph B. The title ofthis paragraph should be "Cell 4A or 4B Beach Elevation," as needed and applicable with paragraph 2 above. The body of that paragraph should indicate that the beach elevation survey will be in Cell 4. A, or Cell 4B as applicable. (If Cell 4B becomes approved for use, it then will be is no longer necessary to establish freeboard elevation for Cell 4A). Denison Response: 3.a.(1) The heading has been changed as requested. 3.a.(2) The requested text "Elevation of Beach Area with the Highest Elevation (monthly)," has been added to Cell 4B only. As previously stated, Denison is requesting UDEQ approval of the DMT Plan as the last action prior to the use of Cell 4B, and as such the requested change to the Cell 4A weekly inspection is not necessary. 3.b. See response to 3.a.(2) above. 4. Please correct miscellaneous errors noted at the following locations on the subject submitted redline DMT Plan copy: a. The third paragraph of page 2, and in paragraph a) below it, the deletion and relocation of a sentence is erroneous. b. Last paragraph of page 3, the elevations listed for the lowest points on the flexible membrane liners . for Cells 4A and 4B conflict with the elevations listed in Appendix A (page 33 of the redline copy) for Cells 4A. and 4B. c. On page 11 heading III, (used for the Roberts Pond) should be a heading IV. OENISO MINES Letter to Mr. Rusty Lundberg January 12, 2011 Page 4 d. In Section 6.3, the fifth paragraph, the first number in the parenthetical phase appears it should be 40 rather than 45.72. e. On page 28 ofthe clean copy, corresponding to p. 33 ofthe red-line copy, for Cell 4A the FML bottom elevation line needs to be right justified. f On page 33, paragraph number 2, the statement "Pump Timer set at 15 min on ...," needs to be deleted. g. On page 36, the asterisk footnote shown refers to an elevation which appears to apply only to Cell 4A. The footnote needs to be adjusted somehow include the elevation that applies to Cell 4B as well. Denison Response: These changes have been made in the attached DMT Plan Revision 11.1. The Cell 4A & 4B O&M Plan. 11/2010 Revision Denison 2.0. ofthe submitted red-line copy: I. Figure 6B does not follow the same logic as Figure 6A I.e., the lowest FML elevation above the sump level is not 1.5-feet above the sump bottom (for the 18-inch diameter collection pipe) as in Figure 6A. Please explain and justify this difference. II. On page 11, in two separate paragraphs numbered I and 2, the second and the last sentence respectively, contain a parenthetical phase that must be deleted or adjusted, as it is incorrect III. On page 14, in the third sentence the parenthetical phrase must be deleted or adjusted, as it is incorrect. IV. Also, on page 14, the second to last sentence from the bottom ofthe page, beginning with, "Each pump is equipped with...," refers to distances of 2.25 feet and 9-inches. These distances appear to not be applicable for the Cell 4B sump and respecting Figure 6S. Please revise this sentence and or figure, to be correct for Cell 4B as well. V. On page 15, the last sentence of the first paragraph on that page must specify what Figure it refers to. VI. Page 17, the third paragraph states," Condition 10.3 states that...," however, current License Condition 10.3 does not state the verbiage quoted after that sentence. Please adjust this paragraph with the proper references and verbiage, as applicable. VII. Beginning on page 17, rewrite the section ofthe O&M Plan titled "Cell 4 A Solution Freeboard Calculation," including the title of that section. This will need to be done according to DUSA 's application of the paragraph numbered 2, under the DMT Plan comment section of this letter Vlll: Please correct miscellaneous errors noted at the following locations on the subject red-lined copy of the Cell 4A and 4B BAT O&M Plan: a. On page 6, paragraph .2, add a sentence which describes that the non-woven geotextile material is also overlain at the surface by a woven geotextile fabric, which is ballasted laterally by sandbags on each side of the backbone gravel berm. b. The above item also must be added to paragraph e.2 on page 3 and 4. c. On page 6, paragraph e.3, also add a sentence which describes that the non-woven geotextile material is also overlain at the surface by a woven geotextile fabric, which is ballasted by sandbags. d. The above item also must be added to paragraph e.3 on page 4. e. Page 20, entry 11 on the Attachments list needs to be updated, and the sentence ended with "DMTMonitoring Plan." Denison Response: DENISO MINES Letter to Mr. Rusty Lundberg January 12, 2011 Page 5 I. Figure 6B is correct. The lowest FML above the sump level is 2.06 feet for Cell 4B. II. The phrase has been deleted from both paragraphs as requested. III. The phrase has been deleted as requested. IV. The text has been corrected to reflect the actual conditions in Cell 4B as shown in Figure 6B, which is correct. V. Figure 5 was referenced in the previous version and no correction is required. VI. The correct verbiage has been added. VII. See response to 3.a.(2) above. VIII. Items a through e have been corrected or amended as requested. Please contact the undersigned if you have any questions or require any further information. Yours very truly, DENISON MINES (USA) CORP. Klo Ann Tischler Director, Compliance and Permitting cc: David C. Frydenlund Harold R. Roberts David E. Turk K. Weinel Central files DENISO MINES January 10, 2011 VIA E-MAIL AND OVERNIGHT DELIVERY Mr. Rusty Lundberg Utah Department of Environmental Quality 195 North 1950 West P.O. Box 144810 Salt Lake City, UT 84114-4820 Re: State of Utah Ground Water Discharge Permit ("GWDP") No. UGW370004 Denison Mines (USA) Corp. 1050 17th Street, Suite 950 Denver, CO 80265 USA Tel: 303 628·7798 Fax: 303389-4125 www.denisonmines.com Transmittal of Revised Documents Addressing White Mesa Uranium Mill New Cell4B and Response to Division of Radiation Control ("DRC") Letter of January 6, 2011 Regarding Comprehensive Comments on Proposed Revised Plans Dear Mr. Lundberg : This letter transmits Denison Mines (USA) Corp's proposed revisions to the Tailings Management System and Discharge Minimization Technology Monitoring ("DMT") Plan, and the Best Available Technology Operations and Maintenance ("BAT O&M") Plan for the White Mesa Mill which are currently pending UDEQ approval. This letter also responds to DRC's letter of January 6, 2011 requesting additional changes to previously submitted versions of these documents. Per DRC's letter, we understand that the Contingency Plan will be addressed separately and changes will not be tied to approval for use of Cell 4B or the New Decontamination Pad. DRC received the October 11, 2010 letter requesting changes to previously submitted versions of the DMT Plan BAT O&M Plan, and Contingency Plan. To address those comments and other changes necessary for operation of Cell 4B, Denison submitted on November 12, 2010 red line and clean copy revisions of those documents entitled DMT Plan Revision 11, BAT O&M Plan Revision 2.0 and Contingency Plan Revision 4.0. DRC reviewed those submittals and requested additional changes to the DMT and BAT O&M Plans in the letter of January 6, 2011. Denison has accepted all the changes submitted on November 12, 2010 to create new black-line copies of the DMT and BAT O&M Plans, and has prepared the additional changes, in response to DRC's January 6, 2011 letter, as redlined markups, entitled DMT Plan 11.1 and BAT O&M Plan Revision 2.1, These revisions have been provided, respectively, as Attachments 1 and 2 to this letter. For ease of review, both of the revised documents have also been provided as clean file versions with all changes accepted. Denison requests that UDEQ review and approve the versions attached to this letter, which consolidate into one set of documents all changes submitted by Denison since September 2008, for which Denison is awaiting DRC approval. N:\Cell 4B\January 2011 Submittals and Revisions for Cell 4B\01.1 0.11 Transmittal to ORC Plan Revisions for Cell4B.doc Letter to Mr. Rusty Lundberg January 12, 2011 Page 2 We have also provided, below, specific responses to each request in UDEQ's January 6, 2011 letter. The sections and numbering of the remainder of this letter follow the DRe January 6, 2011 letter. Each UDEQ request is shown in italics, below, followed by Denison's response. DEQ Comments and Responses The Contingencv Plan (1112010 Revision: DUSA-4J Please be aware that in order to expedite the Cell 48 review process, that DRC review of the Contingency Plan will be addressed under separate cover, proceed independently, and not be tied to the use of the NDP nor Cell 48. The following is noted for future reference: A. In the subject November 12, 2010 letter, DUSA provides proposed red-line and clean versions of the Contingency Plan version noted, which include aspects regarding Cell 48. 8. The third paragraph as well as Section 2 . a. 1 of a September2 ,2010 DUSA letter discusses contingency plan comments in our May 10,2010 letter. Denison Response: No response required. The DMT Plan (11/2010 Revision: DUSA-11 1. We acknowledge a section of paragraph 3 . 1. e.i. D has been changed appropriately to read that, or ••• The depth to water from the top ... of any of the three (3) observation ports to the standing water shall be no less than 6.2 feet. " It appears that incorporation of this item into an approved DMT Plan would complete the issues regarding the NDP with respect to DMT Plan adjustments. Denison Response: No response required. 2. The DMT Plan (as well as the O&M Plan), incorporating necessary items for Cell 48, must be approved prior to DRC authorization of use for Ce1l48. Regarding freeboard requirements, the Plans proposed by the subject DUSA November 12,2010 letter make the assumption that Cell 48 is currently authorized for use, and it is not necessary to establish a freeboard for CeIl4,A. However, this is incorrect. This approach DUSA has taken appears to necessitate one of the following: a. That the last action prior to authorizing use of Cell 48 must be the approval of the DMT Plan (and the O&M Plan), or b, To obtain approval of the DMT and O&M Plans now, DUSA change the plans to establish the freeboard for Cell 4A. to be one of the following, either: (1). The fixed freeboard elevation for Cell 4A, established by the DRC freeboard variance letter of November 20, 2008, or (2). Change the current freeboard determination verbiage proposed in these Plans be more robust. This would include that the freeboard for Cell 4A or Cell 48, as may be applicable, would be established by the rigorous freeboard calculation method outlined in former proposed Plans, but would be written such that if Cell 48 becomes approved, that the freeboard determination method would no longer be needed for or apply to Cell 4A. Please provide DRC your decision to us in this regard, together with any and all necessary corresponding changes to the DMT Plan. OENISOJ)J~ MINES Letter to Mr. Rusty Lundberg January 12, 2011 Page 3 Denison Response: Denison has chosen option (a.) above and will request the approval of the DMT Plan and the O&M Plan as the last action prior to the UDEQ authorization for the use of Cell 4B. As such, the changes requested regarding the reintroduction of Freeboard limits for Cell 4A are not necessary. 3. The following changes in oMT Plan forms, related to tailings beach elevations, are needed due to the need to measure beach elevations in tailings Cells 4A or 4B, as applicable ( per paragraph 2 above). This issue was brought to your attention earlier in our letter dated October 11, 2010. The freeboard for these ponds is determined from the use of such (see paragraph 6.3 and Appendix F of the OMT Plan): a. On page 2B of 49 in Appendix A of the submitted clean copy of the Plan: (1) The heading numbered as one, near the left margin on that page; must state "Pond and Beach elevations ... ," the following earlier proposed oMT Plan versions also contained this provision; (a). 12108 Revision: oenison-7, (b). 05109 Revision: oenison-B, and (c). 3110 Revision:oenison-9. (2) In the corresponding page of the submitted red-line version (i.e. page 33 of 56), item number one contains sections for Cell 4A. and Cell 48. An item (d) stating "Elevation of Beach Area with the Highest Elevation (monthly), " must be added into the sections on this page for each of these cells, as applicable with paragraph 2 above. (Earlier proposed OMT Plan versions contain this item (d) for Cell 4A, in the versions given in paragraph 3.a. above). b. Section 3.1. d. vii, paragraph C should be labeled as paragraph B. The title of this paragraph should be "Cell 4A or 4B Beach Elevation, " as needed and applicable with paragraph 2 above. The body of that paragraph should indicate that the beach elevation survey will be in Cell 4.A, or Cell 4B as applicable. (If Cell 4B becomes approved for use, it then will be is no longer necessary to establish freeboard elevation for Cell 4A). Denison Response: 3.a.(1) The heading has been changed as requested. 3.a.(2) The requested text "Elevation of Beach Area with the Highest Elevation (monthly)," has been added to Cell 4B only. As previously stated, Denison is requesting UDEQ approval of the DMT Plan as the last action prior to the use of Cell 4B, and as such the requested change to the Cell 4A weekly inspection is not necessary. 3.b. See response to 3.a.(2) above. 4. Please correct miscellaneous errors noted at the following locations on the subject submitted redline oMT Plan copy: a. The third paragraph of page 2, and in paragraph a) below it, the deletion and relocation of a sentence is erroneous. b. Last paragraph of page 3, the elevations listed for the lowest points on the flexible membrane liners for Cells 4A and 4B conflict with the elevations listed in Appendix A (page 33 of the redline copy) for Cells 4A. and 4B. c. On page 11 heading III, (used for the Roberts Pond) should be a heading IV. OENISOJ)~~ MINES Letter to Mr. Rusty Lundberg January 12, 2011 Page 4 d. In Section 6.3, the fifth paragraph, the first number in the parenthetical phase appears it should be 40 rather than 45.72. e. On page 28 of the clean copy, corresponding to p. 33 of the red-line copy, for Cell 4A the FML bottom elevation line needs to be right justified. f On page 33,paragraph number 2, the statement "Pump Timer set at 15 min on ... ," needs to be deleted. g. On page 36, the asterisk footnote shown refers to an elevation which appears to apply only to Cell 4A. The footnote needs to be adjusted somehow include the elevation that applies to Cell 4B as well. Denison Response: These changes have been made in the attached DMT Plan Revision 11 .1. The Cell 4A & 4B O&M Plan, 1112010 Revision Denison 2.0, of the submitted red-line copy: I. Figure 6B does not follow the same logic as Figure 6A I.e., the lowest FML elevation above the sump level is not 1.5-feet above the sump bottom (for the 18-inch diameter collection pipe) as in Figure 6A. Please explain and justify this difference. II. On page II, in two separate paragraphs numbered I and 2, the second and the last sentence respectively, contain a parenthetical phase that must be deleted or adjusted, as it is incorrect. III. On page 14, in the third sentence the parenthetical phrase must be deleted or adjusted, as it is incorrect. IV. Also, on page 14, the second to last sentence from the bottom of the page, beginning with, "Each pump is equipped with ... ," refers to distances of 2.25 feet and 9-inches. These distances appear to not be applicable for the Cell 4B sump and respecting Figure 6B. Please revise this sentence and or figure, to be correct for Cell 4B as well. V. On page 15, the last sentence of the first paragraph on that page must specify what Figure it refers to. VI. Page 17, the third paragraph states," Condition 10.3 states that ... ," however, current License Condition 10.3 does not state the verbiage quoted after that sentence. Please adjust this paragraph with the proper references and verbiage, as applicable. VII. Beginning on page 17, rewrite the section of the O&M Plan titled "Cell 4A Solution Freeboard Calculation, " including the title of that section. This will need to be done according to OUSA's application of the paragraph numbered 2, under the OMT Plan comment section of this letter. VIII. Please correct miscellaneous errors noted at the following locations on the subject red-lined copy of the Cell 4A and 4B BA T O&M Plan: a. On page 6 , paragraph .2, add a sentence which describes that the non-woven geotextile material is also overlain at the surface by a woven geotextile fabric, which is ballasted laterally by sandbags on each side of the backbone gravel berm. b. The above item also must be added to paragraph e.2 on page 3 and 4. c. On page 6, paragraph e.3, also add a sentence which describes that the non-woven geotextile material is also overlain at the surface by a woven geotextile fabric, which is ballasted by sandbags. d. The above item also must be added to paragraph e.3 on page 4. e. Page 20, entry 11 on the Attachments list needs to be updated, and the sentence ended with "OMT Monitoring Plan." Denison Response: OENISOJ)~~ MINES Letter to Mr. Rusty Lundberg January 12, 2011 Page 5 I. Figure 6B is correct. The lowest FML above the sump level is 2.06 feet for Cell 4B. II. The phrase has been deleted from both paragraphs as requested. III. The phrase has been deleted as requested. IV. The text has been corrected to reflect the actual conditions in Cell 4B as shown in Figure 6B, which is correct. V. Figure 5 was referenced in the previous version and no correction is required. VI. The correct verbiage has been added. VII. See response to 3.a.(2) above. VIII. Items a through e have been corrected or amended as requested. Please contact the undersigned if you have any questions or require any further information. Yours very truly, DENISON MINES (USA) CORP. ~Chl~ Director, Compliance and Permitting cc: David C. Frydenlund Harold R. Roberts David E. Turk K. Weinel Central files "ENISOJ)~J MINES ATTACHMENT 1 PROPOSED REVISON 11.1 TO DMT PLAN RED-LINED AND CLEAN VERSIONS White Mesa Mill-Standard Operating Procedures Book II: Environmental Protection Manual, Section 3.1 +QIIIGl Revision: Denisonll..l Page 1 of49 WHITE MESA MILL TAILINGS MANAGEMENT SYSTEM AND DISCHARGE MINIMIZATION TECHNOLOGY (DMT) MONITORING PLAN 1. INTRODUCTION This Tailings Management System and Discharge Minimization Technology Monitoring Plan (the "Plan") for the White Mesa Mill (the "Mill") provides procedures for monitoring ofthe tailings cell system as required under State of Utah Radioactive Materials License No. UT1900479 (the "Radioactive Materials License"), as well as procedures for operating and maintenance of monitoring equipment and reporting procedures that are adequate to demonstrate DMT compliance under State of Utah Ground Water Discharge Permit No. 370004 for the Mill (the "GWDP"). This Plan is designed as a systematic program for constant surveillance and documentation of the integrity ofthe tailings impoundment system including dike stability, liner integrity, and transport systems, as well as monitoring of water levels in Roberts Pond and feedstock storage areas at the Mill. The Plan requires daily, weekly, quarterly, monthly and annual inspections and evaluations and monthly reporting to Mill management. 2. DAILY TAILINGS INSPECTIONS The following daily tailings inspections shall be performed: 2.1. Daily Comprehensive Tailings Inspection On a daily basis, including weekends, all areas connected with the four tailings cells will be inspected. Observations will be made of the current condition of each cell, noting any corrective action that needs to be taken. The Environmental or Radiation Technician is responsible for performing the daily tailings inspections. The Radiation Safety Officer may designate other individuals with training, as described in Section 2.4 below, to perform the daily tailings inspection. Observations made by the inspector will be recorded on the Daily Inspection Data form (a copy of which is attached in Appendix A). The Daily Inspection Data form contains an inspection checklist, which includes a tailings cells map, and spaces to record observations, especially those of immediate N'\Cel] 4B\JWlunrr 201 1 Sgbmjllol'!!!!d RC)']S1pnJ forCeU 4IDPMT PI!ll1 01 10 IllTllllinga My!!! Sy",," and OMT MOD Pis" Noy ?1l 10 Ry II I - Rsdlmc;,dgc?1 'e.n 1AIl>!"""",bef.8vbmiu!ll:H!od-&M:t!on,-fj\f£fl!-4l!\BilinttMllltt!iytjmand=PM'f.Mw.P1M-NlI 2mO 8v II White Mesa Mill-Standard Operating Procedures Book II: Environmental Protection Manual, Section 3.1 .tQIIHU Revision: Denisonll.l Page 2 of49 concern and those requiring corrective action. The inspector will place a check by all inspection items that appear to be operating properly. Those items where conditions of potential concern are observed should be marked with an "X". A note should accompany the "X" specifYing what the concern is and what corrective measures will resolve the problem. This observation of concern should be noted on the form until the problem has been remedied. The date that corrective action was taken should be noted as well. Areas to be inspected include the following: CellI, 2, 3, 4A.and 4B, Dikes 1,2,3, 4A-S, 4A-W, 4B- Sand 4B-W wind movement of tailings, effectiveness of dust minimization methods, spray evaporation, Cell 2 spillway, Cell 3 spillway, Cell 3, 4A and 4B liquid pools and associated liquid return equipment, cell leak detection systems, and the wildlife ponds. Operational features of.the tailings area are checked for conditions of potential concern. The following items require visual inspection during the daily tailings i(ll;pecLion: a) Tailings slt.my and SX raffinatc transport systems from the Mill to the active fellO¥/mg items roqt:Hfe ... istiRI iflsfleelieft al:lf~Rg !:flo aSHY tailfRgIj iRBl'JOotiOJr. disposal cell(s), and pool return pipeline and pumps. Daily inspections of the tailings lines are required to be performed when the Mill is operating. The lines to be inspected include the: tailingssluny lines from CeD La lhe acti ve tai lings cell' X raffinaLe lines lhal can discharge into Ccll I, Cell 3. er--CeIl4A or Cc1l4B; the pond l'('ltUI'll line from the tailings area to the Mill' and lines transporting pond solutions from one cell to another. b) CellI. c) Cell 2. d) Cell 3. e) Ce1l4A. t) Ce1l4B. g) Dike structures including dikes 1,2,3, 4A-S, 4A-W, 4B-S and 4B-W. h) The Cell 2 spillway, Cell 3 spillway, Cell 3. tmd-CeIl4A and Cell4B liquid pools and associated liquid return equipment. i) Presence of wildlife and/or domesticated animals in the tailings area, including waterfowl and burrowing animal habitations. White Mesa Mill -Standard Operating Procedures Book II: Environmental Protection Manual, Section 3.1 +QIIIGI Revision: Denison I I.,! Page 3 of49 j) Spray evaporation pumps and lines. k) Wind movement oftailings and dust minimization. Wind movement oftailings will be evaluated for conditions which may require initiation of preventative dust minimization measures for cells containing tailings sand. During tailings inspection, general surface conditions will be evaluated for the following: 1) areas oftailings subject to blowing and/or wind movement, 2) liquid pool size, 3) areas not subject to blowing and/or wind movement, expressed as a percentage of the total cell area. The evaluations will be reviewed on a weekly basis, or more frequently if warranted, and will be used to direct dust minimization activities. I) Observation offlow and operational status ofthe dust control/spray evaporation system(s). m) Observations of any abnormal variations in tailings pond elevations in Cells 1,3, 4A, and 4B. n) Locations of slurry and SX discharge within the active cells. Slurry and SX discharge points need to be indicated on the tailings cells map included in the Daily Inspection Data form. 0) An estimate of flow for active tailings slurry and SX line(s). p) An estimate of flow in the solution return line(s). q) Daily measurements in the leak detection system (LOS) sumps of the tailings cells will be made when warranted by changes in the solution level of the respective leak detection system. The trigger for further action when evaluating the measurements in the CellI and Cell 3 leak detection systems is a gain of more than 12 inches in 24 hours. The solution level in Cell 4A or 4B leak detection system is not allowed to be more than 1.0 foot above the lowest point on the bottom flexible membrane liner (Cell 4A FML elevation is 5555.14 amsl and with the addition of the 1.0 foot of solution the solution elevation is 5556.14 feet amsl.!.. .fEor CeIl4A andCell4B the FML elevation is 5557.50 amsl and with the addition ofthe 1.0 foot of solution the solution elevation is 5558.5Q feet amsl fer CeH--4Jl). If any of these observations are made, the Mill Manager should be notified immediately and the leak detection system pump started. In addition, the requirement to notifY the N;\Co1l4B\1MUllry 7QII Subml1l.r. Md Smolo", Cor Coli 401PMT riM 01.10 II\ThlhnH:! M8Il1 S"lom Q/ld PMT Mpn PIM Ngy 2QIO Ry ! 1 I · Re4I,O!l.dpcN:\£cIHfJ\N!M1!ll!s:r&bmHhlluttd-Reyi"OIlrloti1dHI!ljfoikn ... -MI"Ht"wm-IlDlHlMtMoo-f'lon-N!rti1!W!-JW.H. ~1~~iuoJ~~r~U41M:.,llnl"""A&"I-St>I ....... ~UIH'lorH>!u 11)19 R . II ."""~ White Mesa Mill-Standard Operating Procedures Book II: Environmental Protection Manual, Section 3.1 +QIlHll Revision: Denison I [..l Page 4 of49 Executive Secretary in accordance with Parts I.D.6 and I.G.3 ofthe Groundwater Discharge Permit must be adhered to when the solution level trigger for Ce1l4A or 4B has been exceeded. Whenever the leak detection system pump is operating and the flow meter totalizer is recording, a notation of the date and the time will be recorded on the Daily Inspection Data form. This data will be used in accordance with License Condition 11.3.8 through 11.3.E ofthe Mill's Radioactive Materials License, to determine whether or not the flow rate into the leak detection system is in excess of the License Conditions. r) An estimate ofthe percentage ofthe tailings beach surface area and solution pool area is made, including estimates of solutions, cover areas, and tailings sands for Cells 3, 4A and 4B. Items (a), (m), (n), and (0) are to be done only when the Mill is operating. When the Mill is down, these items cannot be performed. 2.2. Daily Operations Inspection During Mill operation, the Shift Foreman, or other person with the training specified in Section 2.4 below, designated by the Radiation Safety Officer, will perform an inspection ofthe tailings line and tailings area at least once per shift, paying close attention for potential leaks and to the discharges from the pipelines. Observations by the Inspector will be recorded on the appropriate line on the Operating Foreman's Daily Inspection form. 2.3. Daily Operations Patrol In addition to the inspections described in Sections 2.1 and 2.2 above, a Mill employee will patrol the tailings area at least twice per shift during Mill operations to ensure that there are no.-obvious safety or operational issues, such as leaking pipes or unusual wildlife activity or incidences. No record of these patrols need be made, but the inspectors will notifY the Radiation Safety Officer and/or Mill management in the event that during their inspection they discover that an abnormal condition or tailings emergency has occurred. 2.4. Training All individuals performing inspections described in Sections 2.1 and 2.2 above must have Tailings Management System training as set out in the Tailings Inspection Training procedure, which is attached as Appendix B. This training will include a training pack explaining the procedure for performing the inspection and addressing inspection items to be observed. In addition, each N;\Ccn 4BVAI!u!l!Y 2011 SybroUtul. end Revisions (or CdI48\QMT Phm 01 10 I [ITwlinlll MMOI S",em!lld 0 IT MOD riM Nov 2010 Ry II t • Redlin. dRl\N-I££lHByJII'f!'!Dbq-8yIlmi'I!!!t ... IHI."";'ifm Ii1f Cell 4A'Tathn .... ~ft1!D" Q/ff 11M PkH!=N<w-iffil!.&t±l White Mesa Mill -Standard Operating Procedures Book II: Environmental Protection Manual, Section 3.1 +.QIIHU Revision: Denison 11.1 Page 5 of49 individual, after reviewing the training pack, will sign a certification form, indicating that training has been received relative to his/her duties as an inspector. 2.5. Tailings Emergencies Inspectors will notifY the Radiation Safety Officer and/or Mill management immediately if, during their inspection, they discover that an abnormal condition exists or an event has occurred that could cause a tailings emergency. Until relieved by the Environmental or Radiation Technician or Radiation Safety Officer, inspectors will have the authority to direct resources during tailings emergencies. Any major catastrophic events or conditions pertaining to the tailings area should be reported immediately to the M ill Manager or the Radiation Safety Officer, one of whom will notifY Corporate Management. If dam failure occurs, notifY your supervisor and the Mill Manager immediately. The Mill Manager will then notifY Corporate Management, MSHA (303-231-5465), and the State of Utah, Division of Dam Safety (801-538-7200). 3. WEEKLY TAILINGS AND DMT INSPECTION 3.1. Weekly Tailings Inspections Weekly tailings inspections are to be conducted by the Radiation Safety Department and include the following: a) Leak Detection Systems Each tailings cell's leak detection system shall be checked weekly to determine whether it is wet or dry. Ifmarked wet, the liquid levels need to be measured and reported. In Cell 1 and Cell 3 the leak detection system is measured by use of a pipe that is removed from the system which will indicate the presence of solutions in the LDS system. The Cell 4A and 4B leak detection systems are monitored on a continuous basis by use of a pressure transducer that feeds water level information to an electronic data collector. The pressure transducer is calibrated for fluid with a specific gravity of 1.0. The water levels are measured every hour and the information is stored for later retrieval. The water levels are measured to the nearest 0.10 inch. The data collector is currently programmed to store 7 days of water level information. The number of days of stored data can be increased beyond 7 days if needed. The water level data is downloaded to a laptop computer on a weekly basis and incorporated into the Mill's environmental monitoring data base, and into the files for weekly inspection reports of the tailings cell leak detection systems N'\CcI! 1D\J,nuwy2011 Submntolsand Rcyj.'QD. rorC$1I1BIOMTP'an OI.l.Q.III'Uilin8'l MODI S .. 'tID and PMI Moo Plan Ncy2010 By II I . Redlin. docN:\GclI-4B\Nret<mhtt6ulmHllof!.and.Rcmi!!!!t-liJr..£t!!-4BI-Iail'nttMslll-Sv!t,em1llMi-QM:f-.Mon-PlAn-NsrclOJ.9.&o±t ~'-4B1N<w<.o!nbe< ubm;UaIHn4-R.""0fI.·~~4&I1=mI,np-Mgn~t!H),""'J!.M_PI~~UI,dGO White Mesa Mill-Standard Operating Procedures Book 11: Environmental Protection Manual, Section 3.1 -l-.QIIlBl Revision: Denisonll~ Page 6 of49 If sufficient fluid is present in the leak detection system of any cell, the fluid shall be pumped from the LOS, to the extent reasonably possible, and record the volume offluid recovered. Any fluid pumped from an LOS shall be returned to a disposal cell. Iffluid is pumped from an LOS, the flow rate shall be calculated by dividing the recorded volume of fluid recovered by the elapsed time since fluid was last pumped or increases in the LOS fluid levels were recorded, whichever is the more recent. This calculation shall be documented as part of the weekly inspection. Upon the initial pumping offluid from an LOS, a fluid sample shall be collected and analyzed in accordance with paragraph 11.3 C. of the Radioactive Materials License. For Cell 4A and 4B, under no circumstance shall fluid head in the leak detection system sump exceed a I-foot level above the lowest point in the lower flexible membrane liner. To determine the Maximum Allowable Daily LOS Flow Rates in the Cell 4A and 4B leak detection systems, the total volume of all fluids pumped from the LOS on a weekly basis shall be recovered from the data collector, and that information will be used to calculate an average volume pumped per day. Under no circumstances shall the daily LOS flow volume exceed 24,160 gallons/day for Ce1l4A or 26,145gallons/day for Cell 4B. The maximum daily LOS flow volume will be compared against the measured cell solution levels detailed on Table IA and IB (for Cells 4A and 4B, respectively) in Appendix E, to determine the maximum daily allowable LDS flow volume for varying head conditions in Cell 4A and 4B. b) Slimes Drain Water Level Monitoring (i) Cell 3 is -nearly full and will commence closure when filled. Cell 2 is partially reclaimed with the surface covered by platform fill. Each cell has a slimes drain system which aids in dewatering the slimes and sands placed in the cell; (ii) Cell 2 has a pump placed inside ofthe slimes drain access pipe at the bottom of the slimes drain. As taken from actual measurements, the bottom of the slimes drain is 38 feet below a water level measuring point at the centerline of the slimes drain access pipe, at the ground surface level. This means that the bottom of the slimes drain pool and the location of the pump are one foot above the lowest point of the N.1Cc111IDJMY"'Y 2211 Sybmtllw .. !!d Rc,.mjoo. fQrCcIl4BID/yrUIII! 01 10 11\TaJlln", Mso! Sl'llcm 111" PMT Man Plan Nov 2210 Ry II I • Redlin" docN:\{'t!HB\N&vs:mbWivhmiJlolt1l!ld-llMoi!H!tfor.tcll-4!!ffi!i1!nsH.4t!n~DbfI'=Mo<tI'!oHkl. 2019 8 II White Mesa Mill-Standard Operating Procedures Book II: Environmental Protection Manual, Section 3.1 +.Q IIHll Revision: Denison 11..1 Page 7 of49 FML in Cell 2, which, based on construction reports, is at a depth of 39 feet below the water level measuring point on the slimes drain access pipe for Cell 2; (iii)The slimes drain pump in Cell 2 is activated and deactivated by a float mechanism and water level probe system. When the water level reaches the level of the float mechanism the pump is activated. Pumping then occurs until the water level reaches the lower probe which turns the pump off. The lower probe is located one foot above the bottom of the slimes drain standpipe, and the float valve is located at five feet above the bottom ofthe slimes drain standpipe. The average wastewater head in the Cell 2 slimes drain is therefore less than 5 feetand is below the phreatic surface of tailings Cell 2, about 20 feet below the water level measuring point on the slimes drain access pipe. As a result, there is a continuous flow of wastewater from Cell 2 into the slimes drain collection system. Mill management considers that the average allowable wastewater head in the Cell 2 slimes drain resulting from pumping in this manner is satisfactory and is as low as reasonably achievable. (iv)The Cell 2 slimes drain pump is checked weekly to observe that it is operating and that the water level probe and float mechanism are working properly, which is noted on the Weekly Tailings Inspection Form. If at any time the pump is observed to be not working properly, it will be fixed or replaced within 15 days; (v) Depth to wastewater in the Cell 2 slimes drain access pipe shall be monitored and recorded weekly to determine maximum and minimum fluid head before and after a pumping cycle, respectively. All head measurements must be made from the same measuring point (the notch at the north side of the access pipe), and made to the nearest 0.01 foot. The results will be recorded as depth-in-pipe measurements on the Weekly Tailings Inspection Form; (vi)On a monthly basis, the slimes drain pump will be turned off and the wastewater in the slimes drain access pipe will be allowed to stabilize for at least 90 hours. Once the water level has stabilized (based on no change in water level for three (3) successive readings taken no less than one (1) hour apart) the water level of the wastewater will be measured and recorded as a depth-in-pipe measurement on the Monthly Inspection Data form, by measuring the depth to water below the water level measuring point on the slimes drain access pipe; (vii) No process liquids shall be allowed to be discharged into Cell 2; (viii) If at any time the most recent average annual head in the Cell 2 slimes drain is found to have increased above the average head for the previous calendar year, the Licensee will comply with the requirements of Part I.G.3 ofthe GWDP, including the requirement to provide notification to the Executive Secretary orally within 24 hours followed by written notification; (ix)Because Cell 3 and Ce1l4A are currently active, no pumping from the Cell 3 or Cell 4A slimes drain is authorized. No pumping from the Cell 4B slimes drain will be authorized once it is put into service and while it is active. Prior to initiation of tailings dewatering operations for Cell 3,_Cell 4A, or Cell 4B, a similar procedure will be developed for ensuring that average head elevations in the Cell 3 and Ce1l4A N'\Cpll1D\!WlUllIY 2011 Subm.llnl. Nld BI'Y;.joo. fOr c.n 4B\PMT Pion 0\ 10 I I\TwliDIIJ M"", Sn"m ADd pM! MOD Pion NoY 2QI O By II 1- Redlin. docN;-\Q!!!:!ll1N ..... nboHiubmtIIDHHI-Rll.;:!io!It.fqr£el!-48\Iethng:tMj!lt&to!t'lIHIII!I-Q"ff-MIlItP!wtNI!lt@H).fl"* ~~:.'.ccll 4W1oyembef..SubmilIA\HoId-R<Mti;)M-f....e.,Jl.4sm..J~I\I" yll.m-<IIIil-&M'I'-MOIW'I ..... ~R~ White Mesa Mill-Standard Operating Procedures Book II: Environmental Protection Manual. Section 3.1 +QIIHU Revision: Denison I 1,1 Page 8 of49 slimes drains are kept as low as reasonably achievable, and that the Cell 3, Cell 4A, and Cell 4 slimes drains are inspected and the results reported in accordance with the requirements of the permit." c) Wind Movement a/Tailings An evaluation of wind movement of tailings or dusting and control measures shall be taken ifneeded. d) Tailings Wastewater Pool Elevation Monitoring Solution elevation measurements in Cells 14A, and 4B and Roberts Pond are to be taken by survey on a weekly basis, and the beach area in Cell 4A and 4B with the maximum elevation is to be taken by survey on a monthly basis, as follows: (i) The survey will be performed by the Mill's Radiation Safety Officer or designee (the "Surveyor") with the assistance of another Mill worker (the "Assistant"); (ii) The survey will be performed using a survey instrument (the "Survey Instrument") accurate to 0.01 feet, such as a Sokkai No. B21, or equivalent, together with a survey rod (the "Survey Rod") having a visible scale in 0.01 foot increments; (iii)The reference Points (the "Reference Points") for Cells 14A, and 4B, and Roberts Pond are known points established by professional survey. For Cell 1 and Roberts Pond, the Reference Point is a wooden stake with a metal disk on it located on the southeast corner of Cell I. The elevation ofthe metal disk (the "Reference Point Elevation") for Cell 1 and Roberts Pond is at 5,623.14 feet above mean sea level ("FMSL"). For Cell 3 Cell 4A, and Cell 4B, the Reference Point is a piece of metal rebar located on the south dike of Cell 3. The elevation at the top ofthis piece ofrebar (the Reference Point Elevation for Ce\14A and 4B) is at 5,607.83 FMSL. The Surveyor will set up the Survey Instrument in a location where both the applicable Reference Point and pond surface are visible. For Cell 1 and Roberts Pond, this is typically on the road on the Cell 1 south dike between Cell 1 and Roberts Pond, approximately 100 feet east of the Cell lIRoberts Pond Reference Point. For Cell 4A and Cell 4B, this is typically on the road on the Cell 3 dike approximately 100 feet east ofthe Cell 3 Reference Point; (iv)Once in location, the Surveyor will ensure that the Survey Instrument is level by centering the bubble in the level gauge on the Survey Instrument; (v) The Assistant will place the Survey Rod vertically on the Reference Point (on the metal disk on the Cell lIRoberts Pond Reference Point on the top of the rebar on the Cell 4A and 4B Reference PoinL T~e_ ~~sis!~n! ~jl1 ~I!s_u~e_ tp~t_t~~ §~ry~y __ J _ --{ Formatted: Not Highlight Rod is vertical by gently rocking the rod back and forth until the Surveyor has established a level reading; N,IC"U 4BVMuAQ' 201 I Subm;UII\' pnd Rcyjllgn. for Cell ~B\QMT PIm! 01 I Q I lITailin8' MUD! SyJIom ood PM.,. Mon Pion Nov 2010 By II I - ROJIUn"docNt\Ge]l-4l!\N!rtcmbo!-SubmiH"IHn!I-JlI:yjJjnn:t-!l!f.-f.gJ!-1f11ifA11HItIt-Mgnt,s"",,:m-wHl Q!f[ !lon-f1kvt1>kt;2!lK!:Ry-H: ~,""II\N~ubmiIIillHllld·R .. ·""._fo<-G<ll-4BlTruhl,gHilgnHiyo_td Qt.O'Mon~llI-R~ White Mesa Mill -Standard Operating Procedures Book 11: Environmental Protection Manual, Section 3.1 +Q llIGl Revision: Denisonll~ Page 9 of49 (vi) The Surveyor will focus the cross hairs of the Survey Instrument on the scale on the Survey Rod, and record the number (the "Reference Point Reading"), which represents the number of feet the Survey Instrument is reading above the Reference Point; (vii) The Assistant will then move to a designated location where the Survey Rod can be placed on the surface of the main solution pond in the Cell 1, Cell 4A, CeIl4B, or Roberts Pond, or the area of the beach in Cell 4A or Cell 4B with the highest elevation, as the case may be. These designated locations, and the methods to be used by the Assistant to consistently use the same locations are as follows: A. Pond Surface Measurements L Cell 4A The Assistant will walk down the slope in the northeast corner of Cell 4A and place the Survey Rod at the liquid level. II. Ce\14B The Assistant will walk down the slope in the northwest corner of Cell 4B and place the Survey Rod at the liquid level. IlL Cell 1 A mark has been painted on the north side of the ramp going to the pump platform in Cell I. The Assistant will place the Survey Rod against that mark and hold the rod vertically, with one end just touching the liquid surface; and Roberts Pond A mark has been painted on the railing of the pump stand in Roberts Pond. The Assistant will place the Survey Rod against that mark and hold the rod vertically, with one end just touching the liquid surface. Based on the foregoing methods, the approximate coordinate locations for the measuring points for Roberts Pond and the Cells are: Northing Easting Roberts Pond 323,041 2579,697 Cell 1 322,196 2,579,277 Cell 4A 320,300 2,579,360 Ce1l4B 320,690 2,576,200 NICcJl4A\lnollWY 201 I Sybmjual! and RC\1lons Cor Cell "810M]' Pion 01 IQ I llInihnl!5 MPJI! SY!ltm IIld OM! MOil riM Nov lOlD Ry II I • Bedim. docNt\GvlHB\N(!\'OIft!tet.iiulml1ltilIs-gpd-SmajpM.{""'-'<'IHBlT"';ijo!WdsnHM!wtood-QM'F-MOft:fl)an-Nw2QlfI.B,rlt ~Nf\G"U-4~.mber-8ubmittfth-Blld4u",iti"n5-'roo{;el~1~gnr8yol..,.-and-~~l;dao +----{ Formatted: Tab stops: 1.25", Left + Not at 1" 1 White Mesa Mill-Standard Operating Procedures Book 11: Environmental Protection Manual, Section 3.1 +QI /I Gl Revision: Denison I 1..1. Page 10 of49 Ga· These coordinate locations may vary somewhat depending on solution elevations in the Pond and Cells; Celt-4B Beach Elevation The Assistant will place the Survey Rod at the point on the beach area of Cell 4B that has the highest elevation. Ifit is not clear which area of the beach has the highest elevation, then multiple points on the beach area will be surveyed until the Surveyor is satisfied that the point on the Cell 4B beach area with the highest elevation has been surveyed. If it is clear that all points on the Cell 4B beach area are below 5,593 FMSL, then the Surveyor may rely on one survey point; (viii) The Assistant will hold the Survey Rod vertically with one end of the Survey Rod just touching the pond surface. The Assistant will ensure that the Survey Rod is vertical by gently rocking the rod back and forth until the Surveyor has established a level reading; (ix)The Surveyor will focus the cross hairs of the Survey Instrument on the scale on the Survey Rod, and record the number (the "Pond Surface Reading"), which represents the number of feet the Survey Instrument is reading above the pond surface level. The Surveyor will calculate the elevation of the pond surface as FSML by adding the Reference Point Reading for the Cell or Roberts Pond, as the case may be, to the Reference Point Elevation for the Cell or Roberts Pond and subtracting the Pond Surface Reading for the Cell or Roberts Pond, and will record the number accurate to 0.01 feet. e) Decontamination Pads (i) New Decontamination Pad The New Decontamination Pad is located in the southeast corner of the ore pad, near the Mill's scale house. A. In order to ensure that the primary containment of the New Decontamination Pad water collection system has not been compromised, and to provide an inspection capability to detect leakage from the primary containment, vertical inspection portals have been installed between the primary and secondary containments; B. These portals will be visually observed on a weekly basis as a means of detecting any leakage from the primary containment into the void N·\C.II 1!!VMUmy 2911 SUbmillab Md Rnons for Cpll 4B1PMT PIM 01 10 IIIT"jlja .. Mga! SYJu:m ODd PM! Man riM Nov 201 0 Ii. II ) • Rcdllaa.daaN!W1>II-4B\ !M!!!Ix:r-Ijtibn"I!piHqd-RHi!li!Jnt-lj!r£<!H-tBI'foj\t!!!ftMtmt.Syo!~v-I± ~\Gel~B\N.,....nbefo&lbtn!llOb-Md-ltoYiSlOtoHOI-<:~KB\·r.nll~' )'O\ ... ~oo-Piaft.Noy..»IO-&..-+k~ ... White Mesa Mill-Standard Operating Procedures Book II: Environmental Protection Manual, Section 3.1 +QlIHU Revision: Denisonll~ Page I I of49 between the primary and secondary containment. The depth to water in each portal will be measured weekly, by physically measuring the depth to water with an electrical sounding tape/device. All measurements must be made from the same measuring point and be made to the nearest 0.01 foot; C. These inspections will be recorded on the Weekly Tailings Inspection form; D. The water level shall not exceed 0.1 0 foot above the concrete floor in any standpipe, at any time. This will be determined by subtracting the weekly depth to water measurement from the distance from the measuring point in the standpipe to the dry concrete floor The depth to water from the top (elevation 5589.8 feet amsl) of any ofthe three (3) observation ports to the standing water shall be no less than 6.2 feet. Depths less than 6.2 feet shall indicate more that 0.1 foot of standing water above the concrete floor (elev. 5583.5 feet amsl), and shall indicate a leak in the primary containment. E. Any observation of fluid between the primary and secondary containments will be reported to the Radiation Safety Officer (RSO). F In addition to inspection of the water levels in the standpipes, the New Decontamination Pad, including the concrete integrity of the exposed surfaces ofthe pad, will be inspected on a weekly basis. Any soil and debris will be removed from the New Decontamination Pad immediately prior to inspection ofthe concrete wash pad for cracking. Observations will be made of the current condition of the New Decontamination Pad. Any abnormalities relating to the pad and any damage to the concrete wash surface of the pad will be noted on the Weekly Tailings Inspection form. Ifthere are any cracks greater than 118 inch separation (width), the RSO must be contacted. The RSO will have the responsibility to cease activities and have the cracks repaired. (ii) Existing Decontamination Pad The Existing Decontamination Pad is located between the northwest comer ofthe Mill's maintenance shop and the ore feeding grizzly. A. The Existing Decontamination Pad will be inspected on a weekly White Mesa Mill-Standard Operating Procedures Book II: Environmental Protection Manual, Section 3.1 +QIIlGl Revision: Denison 1 1..1 Page 12 of 49 j) Summary basis. Any soil and debris will be removed from the Existing Decontamination Pad immediately prior to inspection of the concrete wash pad for cracking Observations will be made of the current condition of the Existing Decontamination Pad, including the concrete integrity of the exposed surfaces of the pad. Any abnormalities relating to the pad and any damage or cracks on the concrete wash surface of the pad will be noted on the Weekly Tailings Inspection form. If there are any cracks greater than 1/8 inch separation (width), the RSO must be contacted. The RSO will have the responsibility to cease activities and have the cracks repaired. In addition, the weekly inspection should summarize all activities concerning the tailings area for that particular week. Results of the weekly tailings inspection are recorded on the Weekly Tailings and DMT Inspection form. An example of the Weekly Tailings and DMT Inspection form is provided in Appendix A. 3.2. Weekly Inspection of Solution Levels in Roberts Pond On a weekly basis, solution elevations are taken on Roberts Pond, in accordance with the procedures set out in Section 3.1 d) above. The Weekly solution level in Roberts Pond is recorded on the Weekly Tailings and DMT Inspection form. Based on historical observations, the FML at the Pond Surface Reading area for Roberts Pond, is approximately six inches above the lowest point on the pond's FML. Ifthe pond solution elevation at the Pond Surface Reading area is at or below the FML for that area, the pond will be recorded as being dry. 3.3. Weekly Feedstock Storage Area Inspections Weekly feedstock storage area inspections will be performed by the Radiation Safety Department to confirm that: a) the bulk feedstock materials are stored and maintained within the defined area described in the GWDP, as indicated on the map attached hereto as Appendix D; b) a 4 ft. buffer is maintained at the periphery ofthe storage area which is absent bulk material in order to assure that the materials do not encroach upon the boundary ofthe storage area; and c) all alternate feedstock located outside the defined Feedstock Area are maintained within water tight containers. N-\Ccll 4BVnnuIlI'Y 201' Sybm]l!DI"lnd Royjfion. for CdI4B1PMT PIp!! 01 10! IITB,!JDfl! M8/l1 System I/!ld PM! MOD PIon Noy 2010 Ry II I- Redlin. dpcN.~!HI!W9Y!!mb9f=Sllbmjl"'*nntf.!!tw";lHlffor£rlHB\IoIHn!!:l-M~M=f..M?JI:iII~tlHb:H­ ~!H{I\NfW.",beHlubmitIlllHnd-Rev""'~J.4fIl,.Hihn8,,·M8ftI-S1,"em-ond-PM'I'-Moo-Pl .. H'Iil, 2Q1Q R. II okItin doo White Mesa Mill-Standard Operating Procedures Book II : Environmental Protection Manual, Section 3.1 +.QI/lGI Revision: Denison I 1..1 Page 13 of49 The results of this inspection will be recorded on the Ore Storage/Sample Plant Weekly Inspection Report, a copy of which is contained in Appendix A. Any variance in stored materials from this requirement or observed leaking alternate feedstock drums or other containers will be brought to the attention of Mill Management and rectified within 15 days. 4. MONTHLY TAILINGS INSPECTION Monthly tailings inspections will be performed by the Radiation Safety Officer or his designee from the Radiation Safety Department and recorded on the Monthly Inspection Data form, an example of which is contained in Appendix A. Monthly inspections are to be performed no sooner than 14 days since the last monthly tailings inspection and can be conducted concurrently with the quarterly tailings inspection when applicable. The following items are to be inspected: a) Tailings Slurry Pipeline When the Mill is operating, the slurry pipeline will be inspected at key locations to determine pipe wear. Pipe thickness will be measured using an ultrasonic device by either the radiation safety staff or other trained designees. The critical points of the pipe include bends, slope changes, valves, and junctions, which are critical to dike stability. These locations to be monitored will be determined by the Radiation Safety Officer or his designee from the Radiation Safety Department during the Mill run. b) Diversion Ditches Diversion ditches 1, 2 and 3 shall be monitored monthly for sloughing, erosion, undesirable vegetation, and obstruction offlow. Diversion berm 2 should be checked for stability and signs of distress. c) Sedimentation Pond Activities around the Mill and facilities area sedimentation pond shall be summarized for the month. d) Overspray Dust Minimi=ation The inspection shall include an evaluation of overspray minimization, if applicable. This entails ensuring that the overspray system is functioning properly. In the event that overspray is carried more than 50 feet from the cell, the overspray system should be immediately shut-off. N-\CSII 4BV.nuAly20! I Sybm!]llllund Rcvj"on. forCc!l4IJ1OMTPIM!! 01 10 lIlIa/lin ... MW'iSyl\c1!! and PM! Man riM Nov 2010 By 1],1 • Bodhng dooNJ,!;dl-4B1N!\mnbod;!Ibmjllql!-U!!d-R""';"IjmH~I!" .. ~""'I S',",t'fttiIfHIPb9'-MRn1'l~IQ.Rrlt ~N!\(.~~ubm~lUb-~~l-4fI\'feil,~~t-NiI. 2lIIO 11."11 ~ White Mesa MiIl-Standard Operating Procedures Book 11: Environmental Protection Manual, Section 3.1 e) Remarks +.QI 11 !ll Revision: Denisonll.l Page 14 of49 A section is included on the Monthly Inspection Data form for remarks in which recommendations can be made or observations of concern can be documented. j) Summary of Daily, Weekly and Quarterly Inspections The monthly inspection will also summarize the daily, weekly and, if applicable, quarterly tailings inspections for the specific month. In addition, settlement monitors are typically surveyed monthly and the results reported on the Monthly Inspection Data form. 5. QUARTERLY TAILINGS INSPECTION The quarterly tailings inspection is performed by the Radiation Safety Officer or his designee from the Radiation Safety Department, having the training specified in Section 2.4 above, once per calendar quarter. A quarterly inspection should be performed no sooner than 45 days since the previous quarterly inspection was performed. Each quarterly inspection shall include an Embankment Inspection, an Operations/Maintenance Review, a Construction Review and a Summary, as follows: a) Embankmenllnspection The Embankment inspection involves a visual inspection ofthe crest, slope and toe of each dike for movement, seepage, severe erosion, subsidence, shrinkage cracks, and exposed liner. b) Operations/Maintenance Review The Operations/Maintenance Review consists of reviewing Operations and Maintenance activities pertaining to the tailings area on a quarterly basis. c) Construction Review The Construction Review consists of reviewing any construction changes or modifications made to the tailings area on a quarterly basis. N'\C,111BVnnullrt ~O\ I Submittal' pod RCOOriQllI for CcI14B\DMI elm 01 10 II\TruIinp MaJll Syslcm !I!!d oW Moo rIM Nw 2QI 0 Ry II I . Redlin. dQllN;'A1! 4B\N!lYm!milvl>nwlqlt1vt<H\1wi5!tl!!,.,.......c--<iHft\I!lilIn~l'!l.JI\M-No¥i!II9-&t+l- White Mesa Mill-Standard Operating Procedures Book 11: Environmental Protection Manual, Section 3.1 d) Summary +QIIHU Revision: Denison I t l Page 15 of49 The summary will include all major activities or observations noted around the tailings area on a quarterly basis. If any of these conditions are noted, the conditions and corrective measures taken should be documented in the Quarterly inspection Data form. An example ofthe Quarterly inspection Data form is provided in Appendix A. 6. ANNUAL EV ALUA TIONS The following annual evaluations shall be performed: 6.1. Annual Technical Evaluation An annual technical evaluation of the tailings management system is performed by a registered professional engineer (PE), who has experience and training in the area of geotechnical aspects of retention structures. The technical evaluation includes an on-site inspection of the tailings management system and a thorough review of all tailings records for the past year. The Technical Evaluation also includes a review and summary of the annual movement monitor survey (see Section 5.2 below). All tailings cells and corresponding dikes will be inspected for signs of erosion, subsidence, shrinkage, and seepage. The drainage ditches will be inspected to evaluate surface water control structures. In the event tailings capacity evaluations (as per SOP PBL-3) were performed for the receipt of alternate feed material during the year, the capacity evaluation forms and associated calculation sheets will be reviewed to ensure that the maximum tailings capacity estimate is accurate. The amount oftailings added to the system since the last evaluation will also be calculated to determine the estimated capacity at the time of the evaluation. Tailings inspection records will consist of daily, weekly, monthly, and quarterly tailings inspections. These inspection records will be evaluated to determine if any freeboard limits are being approached. Records will also be reviewed to summarize observations of potential concern. The evaluation also involves discussion with the Environmental and/or Radiation Technician and the Radiation Safety Officer regarding activities around the tailings area for the past year. During the annual inspection, photographs ofthe tailings area will be taken. The training of individuals will be reviewed as a part of the Annual Technical Evaluation. White Mesa Mill -Standard Operating Procedures Book 11 : Environmental Protection Manual, Section 3 I +QIIlIU Revision: Denison Il~ Page 16 of 49 The registered engineer will obtain copies of selected tailings inspections, along with the monthly and quarterly summaries of observations of concern and the corrective actions taken. These copies will then be included in the Annual Technical Evaluation Report. The Annual Technical Evaluation Report must be submitted by November 15th of every year to: Directing Dam Safety Engineer State of Utah, Natural Resources 1636 West North Temple, Suite 220 Salt Lake City, Utah 84116-3156 6.2. Movement Monitors A movement monitor survey is to be conducted by a licensed surveyor annually during the second quarter of each year. The movement monitor survey consists of surveying monitors along dikes 3-S, 4A-W, and 4A-S to detect any possible settlement or movement of the dikes. The data generated from this survey is reviewed and incorporated into the Annual Technical Evaluation Report ofthe tailings management system. 6.3. Freeboard Limits The freeboard limits set out in this Section are intended to capture the Local 6-hour Probable Maximum Precipitation (PMP) event, which was determined in the January 10, 1990 Drainage Report (the "Drainage Report") for the White Mesa site to be 10 inches. The flood volume from the PMP event over the Cell 1 pond area plus the adjacent drainage areas, was calculated in the Drainage Report to be 103 acre feet of water, with a wave run up factor of 0.90 feet. The flood volume from the PMP event over the Cell 2 and Cell 3 pond areas, plus the adjacent drainage areas was calculated in the Drainage Report to be 123.4 acre-feet of water. The flood volume from the PMP event over the Cell 4A area was calculated in the Drainage Report to be 36 acre-feet of water (40 acres, plus the adjacent drainage area of3.25 acres), times the PMP oflO inches), with a wave run up factor of 0.77 feet. The flood volume from the PMP event over the Ce1l4B area has been calculated to be 38.1 acre- feet of water (~O acres, plus the adjacent drainage area of 5.72 acres), times the PMP of 10 inches, with a wave run up factor of 0.77 feet. The total pool surface area in Cell 1 is 52.9 acres, in Cell 4A is 40 acres, and in Cell 4B is 40 acres. The top of the flexible membrane liner ("FML") for Cell 1 is 5,618.2 FMSL, for Cell 4A White Mesa Mill -Standard Operating Procedures Book 11: Environmental Protection Manual, Section 3.1 ,JQIIHU Revision: DenisonllJ. Page 17 of49 is 5,598.5 FMSL and for Cell 4B is 5600.4 FMSLL _____ n _______________________ ~ _ --{ Formatted: Not Highlight Based on the foregoing, the freeboard limits for the Mill's tailings cells will be set as follows: 6.3.1. Cell 1 The freeboard limit for Cell 1 will be set at 5,615.4 FMSL. This will allow Cell 1 to capture all of the PMP volume associated with Cell 1. The total volume requirement for Cell 1 is 103 acre feet divided by 52.9 acres equals 1.95 feet, plus the wave run up factor of 0.90 feet equals 2.85 feet. The freeboard limit is then 5,618.2 FMSL minus 2.85 feet equals 5,615.4 FMSL. Under Radioactive Materials License condition 10.3, this freeboard limit is set and is not recalculated annually. 6.3.2. Cell 2 The freeboard limit for Cell 2 is inapplicable, since Cell 2 is filled with solids. All of the PMP volume associated with Cell 2 will be attributed to Cell 4A (and/or any future tailings cells). 6.3.3. Cell 3 The freeboard limit for Cell 3 is inapplicable, since Cell 3 is close to being filled with solids, and all of the PMP flood volume associated with Cell 3 will be attributed to Cell 4B (and/or any future tailings cells). 6.3.4. Ce1l4A The freeboard limit for Cell 4A is inapplicable since all ofthe PMP flood volume associated with Ce1l4A will be attributed to Ce1l4B. A spillway has been added to Ce1l4A to allow overflow into Ce1l4B. 6.3.5. Cell 4B The freeboard limit for Cell 4B will be set assuming that the total PMP volume for Cells 2, 3, 4A, and 4B of 159.4 acre feet will be accommodated in Cell 4B. The procedure for calculating the freeboard limit for Cell 4B is as follows: (aJ When the Pool Surface Area is 40 Acres When the pool surface area in Cell 4B is 40 acres (i.e., when there are no beaches), the freeboard limit for Ce1l4B will be 5,594.6FMSL, which is 5.7 feet below the FML. This freeboard value was developed as follows: PMP Flood Volume Overflow from Cell 4A assuming no storage in Cell 3 or 4A Sum of PMP volume and overflow volume 38.1 acre-feet 159.4 acre-feet 197.5 acre-feet ij-ICgtl4B\1l!!lun 201 I SubmjllnIs Md 8""''';00' forCen 4BIPMI rloo 01 10 II\TJiling. Msnl SY5!e!D alld PMT MoO r iM Ngv 2010 8v II 1- R.dlio" do<tW'-elHB\N~bmil!O,""d-lieyjr!jonH'!!r£tIl-4i\ItjljnI>'tM."HWHm;pKWM%-Mm.fI(on-Hffl!!iQ-Rv=H ~\No .... mII .. S.~~lill.IHM-R~II-4I11'f~~~'H-fOfHlI ... ~!~.doo White Mesa Mill -Standard Operating Procedures Book II: Environmental Protection Manual, Section 3.1 Depth to store PMP an overflow volume = 197.5 acre-feetl40 acres Wave run up factor Total required freeboard +QI/lGl Revision: Denisonl U . Page 18 of49 4.9 feet 0.77 feet 5.7 feet (all values in the above calculation have been rounded 10 the nearest one-tenth of afoot)~ ________ ~ -{ Formatted: Not Highlight (b) When the Maximum Elevation of the Beach Area is 5,594 FMSL or Less When the maximum elevation ofthe beach area in Cel14B is 5594 FMSL or less, then the freeboard limit will be 5,594.6 FMSL, which is the same as in (a) above. This allows for the situation where there may be beaches, but these beaches are at a lower elevation than the freeboard limit established in (a) above, and there is therefore ample freeboard above the beaches to hold the maximum PMP volume. The maximum elevation of the beach area will be determined by monthly surveys performed by Mill personnel in accordance with the Mill's DMT Plan. (c) When the Maximum Elevation of the Beach Area First Exceeds 5,594 FMSL When the maximum elevation of the beach area in Cell 4B first exceeds 5,594 FMSL~ tl!~T!. th~ ___ --I Formatted: Not Highlight freeboard limit for the remainder ofthe ensuing year (period t=O) (until the next November 1) will be calculated when that elevation is first exceeded (the "Initial Calculation Date"), as follows: i) The total number of dry tons oftailings that have historically been deposited into Cell 4B prior to the Initial Calculation Date ("To") will be determined; ii) The expected number of dry tons to be deposited into Cell 4B for the remainder ofthe ensuing year (up to the next November 1), based on production estimates for that period ("L'.o*"), will be determined; iii) L'.o* will be grossed up by a safety factor of 150% to allow for a potential underestimation of the number of tons that will be deposited in the cell during the remainder of the ensuing year. This grossed up number can be referred to as the "modeled tonnage" for the period; iv) The total design tailings solid storage capacity of Cell 4A will be accepted as 2,094,000 dry tons of tailings; v) The available remaining space in Ce1l4B for solids as at the Initial Calculation Date will be calculated as 2,094,000 dry tons minus To; vi) The reduction in the pool surface area for the remainder of the ensuing year will be assumed to be directly proportional to the reduction in the available space in Cell4A for solids. That is, the reduced pool surface area for period t=O ("RPAo"), after the reduction, will be calculated to be: (1 -(L'.o* x 1.5) / (2,094,000 -To)) x 40 acres = RPAo vii) The required freeboard for Cell 4A for the remainder of the period t=O can be calculated in feet to be the wave run up factor for Cell 4B of 0.77 feet plus the quotient of 197.5 acre feet divided by the RP Ao. The freeboard limit for Cell 4B for the remainder of period t=O would then be the elevation of the FML for Cell 48 of N<lCoU4UVADUI!!y201! Submiuo!urul RcyisionsforCcl!4B\I)MT r!m PI 10 IJlIailin .. Mgnl SyllCQ'l!,d Pb-IT Mgn PilI' Npy 2010 Ry 11 I • lIed!!n. dwN;\(iell-4ilNwwlbsr-Sybm;!l!!b~t.foM>elI 1B'.Tei!jIl¥' !I8!Jt-Sytj1:m1!l!d-GM3:.M!l!!=P!qn-N1l'fi9i9-&tl+ White Mesa Mill-Standard Operating Procedures Book II: Environmental Protection Manual, Section 3.1 +.QIIHll Revision: Denison 11.1 Page 19 of49 5594.0 FMSL less this required freeboard amount, rounded to the nearest one-tenth of a foot; and viii) The foregoing calculations will be performed at the Initial Calculation Date and the resulting freeboard limit will persist until the next November 1. An example of this calculation is set out in Appendix F. (d) Annual Freeboard Calculation When the Maximum Elevation of the Beach Area Exceeds 5,594FMSL On November 1 of each year (the "Annual Calculation Date"), the reduction in pool area for the ensuing year (referred to as period t) will be calculated by: i) First, calculating the Adjusted Reduced Pool Area for the previous period (ARPAI.I) to reflect actual tonnages deposited in Cell 4B for the previous period (period t-l). The RPAt.! used for the previous period was based on expected tonnages for period t- 1, grossed up by a safety factor. The ARPAt.! is merely the RPA that would have been used for period t-l had the actual tonnages for year t-l been known at the outset of period t-l and had the RPA been calculated based on the actual tonnages for period t-1. This allows the freeboard calculations to be corrected each year to take into account actual tonnages deposited in the cell as of the date of the calculation. The ARPAt.! can be calculated using the following formula: (1 -~t.! / g,Q~4):1.0_0_-::. It:J2t x_ ~~ ~!:2_~ ~!.{!' ~H ________________________ --{ Formatted: Not Highlight Where: • ~t.! is the actual number of dry tons of tailings solids deposited in Cell 4B during period t-I; • Tt.t is the actual number of dry tons of tailings solids historically deposited in Cell 4B prior to the beginning of period t-1; and • ARPAt_2 is the Adjusted Reduced Pool Area for period t-2. If period t-2 started at the Initial Calculation Date, then ARP At-2 is 40 acres; ii) Once the ARP At-! for the previous period (period t-I) has been calculated, the RP A for the subject period (period t) can be calculated as follows: (1 -(~t* x 1.5) / L2 OJ~.o_09 ~ .T.J2 ~ A~~t:J _=_~~~L ___________________ -_ --{ Formatted: Not Highlight Where: • ~t* is the expected number of dry tons of tailings to be deposited into Cell4B for the ensuing year (period t), based on production estimates for the year (as can be seen from the foregoing formula, this expected number is grossed up by a safety factor of 1.5); • Tt is the actual number of dry tons oftailings solids historically deposited in Cell4B prior to the beginning of period t; and N'ICtU4DVanynry lll! I Sybmjnnltand Bcmi!!!l5 CorCcll dDIDMT PIIII'l 01 10 11\'CoIl!ojll MBIlI Sy.'em Md Dr-IT Moo PlanNqy2010 By II 1- Bcdllnl!.docN:l&!HS\Ne ..... b .. SIl"Ill~:f9f C$il 48lTtj!iftirl.4l!!!tS"" ..... IlfKI:mff:M~QJ9-R.y-It ~~~ilings-MgnI~ .... Id~I_PIIIH'l~lJIgR,II'-OOO White Mesa MiIl-Standard Operating Procedures Book II: Environmental Protection Manual, Section 3.1 .J.QI1191 Revision: Denisonll..l Page 20 of49 • ARPAI•1 is the Adjusted Reduced Pool Area for period t-l, which is the pool surface area for the previous period (period t-1) that should have applied during that period, had modeled tonnages (i.e., expected tonnages grossed up by the 150% safety factor) equaled actual tonnages for the period; iii) The required freeboard for period t can be calculated in feet to be the wave run up factor for Ce1l4B of 0.77 feet plus the quotient of 197.5 acre feet divided by the RPAI. The freeboard limit for Cell 4A for period t would then be the elevation ofthe FML for Cell 4B of 5594.0 FMSL less this required freeboard amount, rounded to the nearest one-tenth of a foot; and iv) The foregoing calculations will be performed at the Annual Calculation Date for period t and the resulting freeboard limit will persist until the next Annual Calculation Date for period t+ 1. An example of this calculation is set out in Appendix F. (e) When a Spillway is Added to Cell 4B that Allows Overflow Into a New Tailings Cell When a spillway is added between Cell 4B and a new tailings cell then, if an approved -freeboard limit calculation method for the new cell is set to cover the entire PMP event for Cells 2, 3, 4A, 4B and the new tailings cell, the freeboard limit for Cell 4B will be inapplicable, except for approved provisions to prevent storm water runoff from overtopping dikes. 6.3.6. Roberts Pond The freeboard limit for Roberts Pond is a liquid maximum elevation of 5,624.0 feet above mean sea level, as specified in the GWDP. 6.4. Annual Leak Detection Fluid Samples In the event solution has been detected in a leak detection system, a sample will be collected on an annual basis. This sample will be analyzed according to the conditions set forth in License Condition II.3.e. The results of the analysis will be reviewed to determine the origin of the solution. 6.5. Annual Inspection of the Decontamination Pads a) New Decontamination Pad During the second quarter of each year, the New Decontamination Pad will be taken out of service and inspected to ensure the integrity of the wash pad's exposed concrete surface. If any abnormalities are identified, i.e. cracks in the concrete with greater than 118 inch separation (width) or any significant deterioration or damage of the pad surface, repairs will be made prior to resuming White Mesa Mill-Standard Operating Procedures Book 11 : Environmental Protection Manual, Section 3.1 +QIIl gl Revision: Denison 11.1 Page 21 of 49 the use ofthe facility. All inspection findings and any repairs required shall be documented on the Annual Decontamination Pad Inspection form. The inspection findings, any repairs required and repairs completed shall be summarized in the 2nd Quarter DMT Monitoring Report due September I of each calendar year. b) Existing Decontamination Pad During the second quarter of each year, the Existing Decontamination Pad will be taken out of service and inspected to ensure the integrity ofthe steel tank. Once the water and any sediment present is removed from the steel tank containment, the walls and bottom of the tank will be visually inspected for any areas of damage, cracks, or bubbling indicating corrosion that may have occurred since the last inspection. If any abnormalities are identified, defects or damage will be reported to Mill management and repairs will be made prior to resuming the use of the facility. All inspection findings and any repairs required shall be documented on the Annual Decontamination Pad Inspection form. A record of the repairs will be maintained as a part of the Annual Inspection records at the Mill site. The inspection findings, any repairs required and repairs completed shall be summarized in the 2nd Quarter DMT Monitoring Report due September 1 of each calendar year. 7. OTHER INSPECTIONS All daily, weekly, monthly, quarterly and annual inspections and evaluations should be performed as specified in Sections 2, 3, 4, 5 and 6 above. However, additional inspections should be conducted after any significant storm or significant natural or man-made event occurs. 8. REPORTING REQUIREMENTS In addition to the Daily Inspection Data, Weekly Tailings Inspection, Monthly Inspection Data and Quarterly Inspection Data forms included as Appendix A and described in Sections 2, 3, 4 and 5 respectively, and the Operating Foreman's Daily Inspection and Weekly Mill Inspection forms described in Sections 2 and 3, respectively, the following additional reports shall also be prepared: 8.1. Monthly Tailings Reports Monthly tailings reports are prepared every month and summarize the previous month's activities around the tailings area. If not prepared by the Radiation Safety Officer, the report shall be submitted to the Radiation Safety Officer for review. The Mill Manager will review the report as well before the report is filed in the Mill Central File. The report will contain a summary of observations of concern noted on the daily and weekly tailings inspections. Corrective measures taken during the month will be documented along with the observations where appropriate. All daily and weekly tailings inspection forms will be attached to the report. A monthly inspection form will also be attached. Quarterly inspection forms will accompany the report when applicable. The report will be signed and dated by the pre parer in addition to the Radiation Safety Officer and the Mill N\Cc1l4BVpnyary 2011 SubmmAlund Reyf5loos (or Ce1l4B\pMT rIM 01 10-' I\T"ljw Mell! Snlpm AJU! PM! Man PI", NI!V 2010 Rv II I · Redline docNAfc:lHmN<......m.er-sybmtfm1m S"i.fon. fur £e]l 4Bll'qj!ittp.M8n\:Syl!lcm QIld RIIT IIIlft£oo·NretilH2-B"ttt ~B~milllllHfld.ll~""""I"of'..£eII-4m:l'eiliflll-M8f'\"&"'IenHnd-DM1'-M..,.pItln-N~!eorHIoo White Mesa Mill-Standard Operating Procedures Book 1 J: Environmental Protection Manual, Section 3 1 Manager. 8.2. DMT Reports +QJIlGl Revision: Denison11..! Page 22 of49 Quarterly reports ofDMT monitoring activities, which will include the following information, will be provided to the Executive Secretary on the schedule provided in Table 5 of the GWDP: a) On a quarterly basis, all required information required by Part 1.F.2 ofthe GWDP relating to the inspections described in Section 3.1(b) (Slimes Drain Water Level Monitoring), 3.1(d) (Tailings Wastewater Pool and Beach Area Elevation Monitoring), 3.2 (Weekly Inspection of Solution Levels in Roberts Pond) and 3.3 (Weekly Feedstock Storage Area Inspections); b) On a quarterly basis, a summary ofthe weekly water level (depth) inspections for the quarter for the presence offluid in all three vertical inspection portals for each of the three chambers in the concrete settling tank system for the New Decontamination Pad, which will include a table indicating the water level measurements in each portal during the quarter; c) With respect to the annual inspection ofthe New Decontamination Pad described in Section 6.5(a), the inspection findings, any repairs required, and repairs completed shall be summarized in the 2nd Quarter report, due September 1 of each calendar year; d) With respect to the annual inspection of the Existing Decontamination Pad described in Section 6.5(b), the inspection findings, any repairs required, and repairs completed shall be summarized in the 2nd Quarter report, due September 1 of each calendar year; and e) An annual summary and graph for each calendar year ofthe depth to wastewater in the Cell 2 slimes drain must be included in the fourth quarter report. After the first year, and beginning in 2008, quarterly reports shall include both the current year monthly values and a graphic comparison to the previous year. N IC.1l 4BVMI!I\O'?0! I SybmillAl. And RMsjon. (or Cell 4BIPMT rloo 01.10 lllTajlin81 MWlI SyUem!!lld PMT Mpn rIM No. 2010 Ry II I . Rcdllnr,docN!IGc!f.4B\NJMmhtftivbmillol ....... 8!wi!ioM{<ri'riHBffiJiIjnat-Mjn!-SYllmtj!n!H)Mf-MI~¥±t ~11-4~bot>&IbnUJIiIIt.""""RcoMi~J-4B\+iujl!lllO"MI!fI+"S)'OIem-tInd-SM+-M<lII PI",,"~r... 2919 R. II .I.-..1oa White Mesa Mill-Standard Operating Procedures Book II: Environmental Protection Manual, Section 3.1 APPENDIX A FORMS +QI/](}l Revision: Denisonll.l Page 230[49 N;\CcIl4OVDnIlOCY 2011 Sl!bml!\n!, Dod Rovision. tin Csll1BIDMI Pjoo OJ 10 II\TBihn ... MMDI System I!)d PMT Moo rll!) Noy '010 By II 1- Redbn.,dOl1N:\($II·4B\NomnPctSvbminoJt..arwHlgyi~tm-M.~klnt.n4 mH-M~ White Mesa Mill -Standard Operating Procedures Book 11: Environmental Protection Manual, Section 3.1 +QI/W! Revision: Denisonll~ Page 24 of49 APPENDIX A (CONT.) DAILY INSPECTION DATA Any Item not "OK" must be documented. A check mark = OK, X = Action Required I. TAILINGS SLURRY TRANSPORT SYSTEM I Inspection Items Conditions of Potential Concern CellI Slurry Pipeline Leaks, Damage, Blockage, Sharp Bends Pipeline Joints Leaks, Loose Connections Pipeline Supports Damage, Loss of Support Valves Leaks, Blocked, Closed Point(s) of Discharge Improper Location or Orientation II. OPERATIONAL SYSTEMS I Inspection Items Conditions of Potential Concern Cell I Water Level Greater Than Operating Level, Large Change Since Previous Inspection Beach Cracks, Severe Erosion, Subsidence Liner and Cover Erosion of cover, Exposure of Liner Liner Observable Liner Damage Cell 2 Cell 2 Inspector: ______ _ Date; ________ _ Accompanied by: ___ _ Time: ________ _ Cell 3 Ce1l4A Ce1l4B Cell 3 Ce1l4A Ce1l4B White Mesa Mill -Standard Operating Procedures Book 11: Environmental Protection Manual, Section 3.1 III. DIKES AND EMBANKMENTS +QIIHU Revision: DenisonlI"l Page 250[49 I InsQection Items Conditions of Potential Dike I-I Dike 1-Dike 2 Dike 3 Dike Dike Dike Dike I Concern lA 4A-S 4A-W 4B-S 4B-W Slopes Sloughs or Sliding Cracks, Bulges, Subsidence, Severe Erosion, Moist Areas, Areas of Seepage Outbreak Crest Cracks, Subsidence, Severe Erosion - IV. FLOW RATES I SluITY Line(s) Pond Return GPM V. PHYSICAL INSPECTION OF SLURRY LINES(S) Walked to Discharge Point Observed Entire Discharge Line VI. DUST CONTROL Dusting Wind Movement of Tailings Precipitation: inches liquid General Meteorological conditions: Ce\l2 S-X Tails ______ yes ______ yes Ce\l3 Spray System ____ ---'No _____ No Ce\l4A Ce\l4B N:ICe1i4BVonupry20J I SUbmilblls IDd RCyl5jQOS (or CJ;U48\DMT Plan 01 10 II\TBilinss MpH System and DMT Mon Plan Nov 2010 Rv II 1 • Redline doc":l&ell 4B\tJ8".~.ti!ffl!ttl!d ~1l"Sicn 4R1jftilillS5 !lg'lp!\Y$! ..... Ad DMT 14e. PI •• ~I. aGIO p,. Ilel.eM dee~I!\(;elI48~18'.-e .. btf8 .. bIflilllls I,ul Be ~5ie", fe. Col! 4811=liliA!1 M&f11 &)51 ....... d 9H+"fell PIIlI! ~hl'Y 2919 Ro 11 .I ..... EI •• White Mesa Mill -Standard Operating Procedures Book 11: Environmental Protection Manual, Section 3.1 VII. DAILY LEAK DETECTION CHECK Cell 1 Leak Checked Detection I I Cell 2 Checked -lQlIHU Revision: Denisonll,.! Page 26 of49 Cell 3 Cell4A Ce1l4B Checked Checked Checked System ___ Wet ___ Dry ___ Wet ___ Dry __ Wet __ Dry __ Wet __ Dry ___ Wet ___ Dry Checked Initia1level Initial level Initial level Initial level Initial level Final Final Final Final Final level level level level level Gal. pumped Gal. pumped Gal. pumped Gal. pumped ___ Gal, pumped -- VIII OBSERVATIONS OF POTENTIAL CONCERN Action Required N,\c.n4B\!puuIIlY2011 S bm' .; U Iltlll$ and RevillAn! for Ccll4BIDMT ' . ~J",!lS Me!! Sm ..... ..wHT . , rIM 01 10.II\TI,I!D8< MilD! SYlkm And PMT M ~ He PI.., ),!!y 2010 R" II ol.A".~8'~I!\{"eIl4B~' ~ slit) Pllln Nov 2010 Bv I \.I -RsdJjnc,dQ!1N~HffiN ,8 _ or ~1IM'II&1s .~d Re";ti_ Iiw Coli IB'l'6ili . """'~I!<I ~ While Mesa MiII-Siandard Operating Procedures Book 11 : Environmemal Prolection Manual. Section 3.1 [MAP OF TAl LING S AREA) -tQ11l91 Revision: Denison IIJ. Page 27 of49 N;\Cc1l 4B\lanunrvl01 I Submi!loJ$ Ind Revillon. for Cc!14IDPMT Plan Ol.IO 1)\Tailings Melli SYllkm and PMI Mon PIAn Noy 2010 Ry II ) -Rcd!jnc.tI!lCN;Gt!~II .. 8 ...... illol! !lId ~"(j,1I 48\i&j!j"t<rM~'\I §: ....... d QUI !jen pin" tl •. 2910 R" II .lenft.d<HlR\Cdl 4B~'~.~1-4B\l=eIIiAg$ M/lIII S)'SMl'Rd QMT >let. Pia. Ney ~9R/I).'-.1k!a White Mesa Mill-Standard Operating Procedures Book II: Environmental Protection Manual, Section 3.1 ,J.Q1IIGI Revision: Denisonll.J. Page 28 of49 Oalc: ______ _ 1. Pond !lJ1d Beach elevations (msl, ft) APPENDIX A (CONT) DENISON MINES (USA) CORP. WEEKLY TAILINGS INSPECTION Inspectors: ____________ _ CellI: (a) Pond Solution Elevation (b) FML Bottom Elevation ___ 5597 __ _ (c) Depth of Water above FML «a)-(b» _____ _ Ce114A: (a)Pond Solution Elevation (b )FML Bottom Elevation __ 5555.14-= (c) Depth of Water above FML «a)-(b» ____ _ CeIl4B: (a)Pond Solution Elevation (e)FML BetleRi Ele~'atieft (b)FML Bottom Elevation 5S75.5 5557.50 (c)Depth of Water above FML «a)-(b» ____ _ Roberts (d)Elevl1tion of Beach Area witll HiMe t Elevation (monthly) Pond: (a)Pond Solution Elevation (b)FML Bottom Elevation ___ 5612.3_ (c)Depth of Water above FML «a)-(b» _____ _ 2. Slimes Drain Liquid Levels Cell 2 Pump functioning properly ___ _ PIHBIl Timer set at 15Riift eft 45 Rim eff ______ ---::Depth to Liquid pre-pump _______ D plh to Liquid Post-pump (all measurements are depth-in-pipe) Pre-pump head is 38'-Depth to Liquid Pre-pump = Post-pump head is 38' -Depth to Liquid Post- pump= __ _ .--- -[ Formatted: Indent: Left: 0.55" .----{ Formatted: Indent: Left: 0.55" .-- --{ Formatted: Indent: Left: 0.55" White Mesa Mill -Standard Operating Procedures Book 11: Environmental Protection Manual, Section 3.1 +QI/IGI Revision: Denisonll.J. Page 29 of49 3. Leak Detection Systems Observation: Celli Cell 2 Cell 3 Ce1l4A Ce1l4B Is LDS wet or __ wet __ wet wet __ wet wet dry? dry dry dry dry dry If wet, Record Ftto Ftto ---Ft to ___ Ftto ---Ft to liquid level: Liquid Liquid Liquid Liquid * Liquid * If sufficient Volume Volume Volume Volume Volume fluid is present, record Flow Flow Flow Flow Flow volume of Rate ---Rate ---Rate ___ Rate ___ Rate ---fluid pumped and flow rate: Was fluid ----..Yes __ no ----..Yes __ no ----..Yes __ no ----..Yes __ no ----..Yes __ no sample collected? Observation: New Decon Pad, New Decon Pad, Ne~ Decon Pad Portal I Portal 2 Portal 3 Is LDS (Portal) __ wet __ dry __ wet __ dry __ wet __ dry wet or dry? If wet, Record Ftto ___ Ftto Ftto liquid level: Liquid Liquid Liquid Ifwet, Report to RSO 4. Tailings Area Inspection (Note dispersal of blowing tailings): 5. Control Methods Implemented:, _____________________ _ 6. RemM~: ______________________________ _ N:\CeU 4BUMUory '01 I Submillal. ondRev,.;on. foc Cell 411lDMT rIm OJ IQ I J\TAihog5 MeD! SY""," A/,d OMI foo PliID NaY 2OJO By II J. Rc;d!jn .. dgrN%js:lJ.4H\Nor.mb .. :8!JI!!Di"·IHOd=R~I_4H'r'FaiIt""'_M~gnfJaretfO'!'=i2W_R¥_H_ ~-.nhc>f-SubRl~e'/I.......r.,..Q,""'BI'I'effl~wt-~~.pI~QIW\~ White Mesa Mill -Stpndard Operating Proc ... 'durcs I.!ook II: Environmentol Protection Manual, Seetion 3.1 7. Contaminated Waste Dump: ,JQIIIQl Revision: I)enisonll.! Poge 30 of49 • Docs Level exceed 12 inches above the lowest point on the bollOln flexible membrane liner ~ elevation..Q[5556.14 amsl for Cell4A and 5558.50 for Ce!l 4B)? no __ y'" If Ce1l4A leak detection system level exceeds 12 inches above the lowest point on the bottom flexible membmne liner (eb'!ltion 5556. I 4 OlllS]), notify supervisor or Mill manager immediately. N"..cal1111\l"1IKY~IJ Syba"'N'ogd Bmy"" f«Ct!J 'HIDMT PM 0[ 10 II\Tajhpu MMIII Snlm! ",4 DMI Mill Pi.. Nm:2010 By II 1. Rr4hntdo<!:j '£.11 111"" .. b, &1 ...... "" ..... ~..tHlf'Fwih". "",! & "'" MId mFf..Mon-Ploo.Jiw.&lHy±l White Mesa Mill -Standard Operating Procedures Book II: Environmental Protection Manual, Section 3.1 APPENDIX A (CONT.) .j.QIIHU Revision: Denisonll.J. Page 31 of49 MONTHL Y INSPECTION DATA Inspector: ____________ _ Date: _________________________ _ 1. Slurry Pipeline: _______________________________________________________ _ Pipe Thickness: ______ {To be measured only during periods when the Mill is operating) 2. Diversion Ditches and Diversion Berm: Observation: Diversion Ditches: Sloughing Erosion Undesirable Vegetation Obstruction of Flow Diversion Benn: Stability Issues Signs of Distress Diversion Ditch 1 Diversion Ditch 2 ~es __ no ~es __ no ~es __ no ~es __ no ~es __ no ~es __ no ~es __ no ~es __ no Diversion Ditch 3 ~es __ no ~es __ no ~es __ no ~es __ no Diversion Benn 2 ~es __ no ~es __ no Comments:. __________________________________ ___ 3. Summary of Activities Around Sedimentation Pond: _________________ __ N'\CJ:1I4B\!MII"'Y lOll SubrnilU!l. and Rcyilil'!lI [or C.Y 4B\DMI PIg!! 01 II) IllTaihn .. Msnt SvslemlDli PMI Moo elM Nov 2010 Ry II I .. Rtdhng d""NJ\(:;eJHfI\N<wl'f!lbt:tfivbmit!g~ti_f;1r.{'c11-4Iffi1Mhn'"' Mont lint .... and mIT !4!l!tP~rulHW+t ~14B\~lo,~llbmiIlS-nnd-l\0Y~-ell ... 48\'Feih"80 .. ~·IsnH>~IO-R~ White Mesa Mill-Standard Operating Procedures Book II: Environmental Protection Manual, Section 3.1 4. Overspray Dust Minimization: Overspray system functioning properly: ___ Jyes ___ no +QIIHll Revision: Denison I I...!. Page 32 of49 Overspray carried more than 50 feet from the cell: ~es ___ no If "yes", was system immediately shut off? ~es __ no Commen~: _____________________________________________________________ _ s. Rcmarks: ___________________________________________________________ __ 6. Settlement Monitors Cell 2 WI: Cell 2W3-S: ____ _ Cell 3-1N: ____ _ Cell 2 W2: Ce1l2EI-N: ____ _ Cell 3-1C: ____ _ Cell 2 W3: Ce1l2El-IS: ____ _ Cell 3-1S: ____ _ Cell 2 W4: Ce1l2EI-2S: ____ _ Ce1l3-2N: ____ _ Cell 2W7-C: ____ _ Cell 2 East: Ce1l2W5-N: ___ _ Cell 2 W7N: ____ _ Cell 2 W7S: CeIl2W6N: ___ _ Cell 2 W6C: Cell 2 W6S: Cell 2 W4N: ___ _ CeIl4A-Toe: Cell 3-2C: ---- Cell 2 W4S: Ce1l3-2S: Cell 2 W5C: ___ _ Cell 2 W5S: ___ _ Cell ~B 7. Summary of Daily, Weekly and Quarterly [nspections: _____________________________ _ 8. Monthly Slimes Drain Static Head Measurement for Cell 2 (Depth-in-Pipe Water Level Reading): 9. Monthly Slimes Drain Static Head Measurement for Cell 3 (Depth-in-Pipe Water level) (after Cell 3 is closed): N:lCgU (B\/bJU!l!fY 2QI I Sub/villi!)' and Revnion. forCcU 1B\1lMI riM 01 10 IllTail!nl!!! Mgnt Svllcm aod D~IT Moo r iM Noy:20I O BY 11,1· Rsdline.dgcN!>&lt4i!INJwmJbsr.StthmH'Q~tont{ri<'ll_4B'ffiIiltIli!.'l=M8'"_8ymmjwd_Ii!Mf_M0!I.pIaIl·NI!'tWibBv±t White Mesa Mill -landard Operating Procedures Oook 11 : Envlronmcntoll'rotection Manual, Section 3.1 AI'PE "OIX (CONT.) +.!J1/191 Revision: Denison II..l Pagel30r49 WHITE MESA MILL TAILINGS MANAGEMENT SYSTEM QUARTERLY INSPECTiON DATA In pector: ____________ _ Date: _______________ __ 1. Embankment Inspection: 2. Operations/Maintenance Review: 3. COAStruction Activities: _____________________ __ 4. ummary: ______________________________ ___ While MI."$lI MIII -Standard Operating PrOttdurc:s I100k II : Environmental ProIet\lon Manual. Sec1ion), I .JOt/IOl Revision: Denisonll.! Page 14 of49 API'ENDIX A (CONT.) ORE STORAG~:ISAMJ'U: PLANT WEEKLY INS I'Ecn ON REPORT Week of ____ through ____ Date of Inspeetion: ______ _ Inspcctor: __________ _ Wemhcr conditions for the week: Blowing dust conditions for the week: COlTCctive actions needed or taken for the week: Arc all bulk feedstock materials stored in the area indicated on the attached diagram: yes: no: comments: Arc all oitenmte feedstock mmerials located outside the area indicated on the auaehed diugram maintained within watcr.ti ght contninCfll: yes: ___ no:.:::::;;;;:: comments (e.g., conditions of oontainer.o): Arc all sumps and low lying areas free of standing solutions? Yes: ___ No: __ _ Ir"No", how was the situation com:cted, supervisor contacted IlIld cOlTCetion date? Is there free standing water or waler nmning ofT orlhe feedstock stockpiles? Yes: No: __ _ Comments:' _________________________________ _ White Mesa MilI -Standard Opcl1l!ing Procedures Rook I I: Environmental rrole<:lion Manool, Section 3.1 Olher oomments: -ijllf191 Revision: OcnisonllJ. Page 3S or49 N''C!I .. m' ..... lIIlI 'kg,.a.". Bm_ .... c.UB\DMT"" Ol Io II\Ye'iouM .. s ......... QMT M,. PI.. NpralllO It II I • bdhn"wttOC."PS trS t • t .. , ",ftllllf&f ." •• (l ...... !)f,ffMe"" 'I. aGllIIl.'cl4 White Mesa Mill-Standard Operating Procedures Book II: Environmental Protection Manual, Section 3.1 APPENDIX A (CONT.) +QI II Gl Revision: Denisonll~ Page 36 of49 ANNUAL DECONTAMINATION PAD INSPECTION Date of Inspection: _______ _ Inspector: __________ _ New Decontamination Pad: Are there any cracks on the wash pad surface greater than 1/8 inch of separation? _Yes _No Is there any significant deterioration or damage of the pad surface? __ Yes __ No Findings: Repair Work Required: Existing Decontamination Pad: Were there any observed problems with the steel tank? __ Yes __ No Findings: Repair Work Required: Note For the annual inspection of the both the Existing and New Decontamination Pads, the annual inspection findings, any repairs required, and repairs completed, along with a summary of the weekly inspections, shall be discussed in the 2nd Quarter report, due September 1 of each calendar year White Mesa Mill-Standard Operating Procedures Book II: Environmental Protection Manual, Section 3.1 APPENDIX B +QlIlGl Revision: Denisonll~ Page 37 of 49 TAILINGS INSPECTOR TRAINING This document provides the training necessary for qualitying management-designated individuals for conducting daily tailings inspections. Training information is presented by the Radiation Safety Officer or designee from the Environmental Department. Daily tailings inspections are conducted in accordance with the White Mesa Mill Tailings Management System and Discharge Minimization Technology (DMT) Monitoring Plan. The Radiation Safety Officer or designee from the Radiation Safety Department is responsible for performing monthly and quarterly tailings inspections. Tailings inspection forms will be included in the monthly tailings inspection reports, which summarize the conditions, activities, and areas of concern regarding the tailings areas. Notifications: The inspector is required to record whether all inspection items are normal (satisfactory, requiring no action) or that conditions of potential concern exist (requiring action). A "check" mark indicates no action required. If conditions of potential concern exist the inspector should mark an "X" in the area the condition pertains to, note the condition, and specity the corrective action to be taken. If an observable concern is made, it should be noted on the tailings report until the corrective action is taken and the concern is remedied. The dates of all corrective actions should be noted on the reports as well. Any major catastrophic events or conditions pertaining to the tailings area should be reported immediately to the Mill Manager or the Radiation Safety Officer, one of whom will notity Corporate Management. Ifdam failure occurs, notity your supervisor and the Mill Manager immediately. The Mill Manager will then notity Corporate Management, MSHA (303-231-5465), and the State of Utah, Division of Dam Safety (801-538-7200). Inspections: All areas of the tailings disposal system are routinely patrolled and visible observations are to be noted on a daily tailings inspection form. Refer to Appendix A for an example ofthe daily tailings inspection form. The inspection form consists ofthree pages and is summarized as follows: 1. Tailings Slurry Transport System: The slurry pipeline is to be inspected for leaks, damage, and sharp bends. The pipeline joints are to be monitored for leaks, and loose connections. The pipeline supports are to be N"',csU 4QVAIluary 2011 SlIlnnllll!!und Rqyj.ion. fQ(Cc!l4BlQMT Ph., OJ 10 IIITII\I"!15 MgOlSYltem PIld PMTMD!l PIAl! NoviGIO Ry II I • Redlin; dooN\lG<!!I-IIDN!lY!!I!Ibct-SubmIU.lHrNf.lI1wHHlntfoM?rli-4!Mqj!m~-QMJ-Mon-PJoo.No 29 I II fly II ~1l-4B\November-8t.lbmlunlHnd.fl~~hfl8O"M8f!I-8_d-9M+-Mon--PI~~ White Mesa Mill-Standard Operating Procedures Book 11: Environmental Protection Manual, Section 3.1 +QIIlGl Revision: Denisonll,l Page 38 of49 inspected for damage and loss of support. Valves are also to be inspected particularly for leaks, blocked valves, and closed valves. Points of discharge need to be inspected for improper location and orientation. 2. Operational Systems: Operating systems including water levels, beach liners, and covered areas are items to be inspected and noted on the daily inspection forms. Sudden changes in water levels previously observed or water levels exceeding the operating level of a pond are potential areas of concern and should be noted. Beach areas that are observed as having cracks, severe erosion or cavities are also items that require investigation and notation on daily forms. Exposed liner or absence of cover from erosion are potential items of concern for ponds and covered areas. These should also be noted on the daily inspection form. Cells 1, 3, 4A and 4B solution levels are to be monitored closely for conditions nearing maximum operating level and for large changes in the water level since the last inspection. All pumping activities affecting the water level will be documented. In Cells 1 and 3, the PVC liner needs to be monitored closely for exposed liner, especially after storm events. It is important to cover exposed liner immediately as exposure to sunlight will cause degradation ofthe PVC liner. Small areas of exposed liner should be covered by hand. Large sections of exposed liner will require the use of heavy equipment These conditions are considered serious and require immediate action. After these conditions have been noted to the Radiation Safety Officer, a work order will be written by the Radiation Safety Officer and turned into the Maintenance Department. All such repairs should be noted in the report and should contain the start and finish date of the repairs. 3. Dikes and Embankments: Inspection items include the slopes and the crests of each dike. For slopes, areas of concern are sloughs or sliding cracks, bulges, subsidence, severe erosion, moist areas, and areas of seepage outbreak. For crests, areas of concern are cracks, subsidence, and severe erosion. When any of these conditions are noted, an "X" mark should be placed in the section marked for that dike. In addition, the dikes, in particular dikes 3, 4A-S, 4A-W, 4B-S, and 4B-W, should be inspected closely for mice holes and more importantly for prairie dog holes, as the prairie dogs are likely to burrow in deep, possibly to the liner. If any ofthese conditions exist, the inspection report should be marked accordingly. N,\C.U4B\1AlnHPY 201 1 Sybm;l!;!ls AIld Boon. (ur Cdl4BIDMT PIAn 01 10 IllTadjnn MIUJI Systom ROd D~!T Moo Plan Noy WIO By II I - Redl,IJ.' d~K8ltitwmH ... &b!!lt!I.IHnd·B!M!!!l!lt{ .... £clHffifti!!o~lctJHlll!H»ff-Mon-jI1vrtNw-2iIAAclt ~I "'~II jB\N.......w-lM>m~"""~\I-<\B\:reiIina.o--M~ .. lHIftd.DM+.Mon-Pl~ White Mesa Mill -Standard Operating Procedures Book 11: Environmental Protection Manual, Section 3.1 4. Flow Rates: -l-QllHll Revision: Denison I 1.1 Page 39 of49 Presence of all flows in and out of the cells should be noted. Flow rates are to be estimated in gallons per minute (OPM). Rates need to be determined for slurry lines, pond return, SX- tails, and the spray system. During non-operational modes, the flow rate column should be marked as "0". The same holds true when the spray system is not utilized. 5. Physical Inspection of Slurry Line(s): A physical inspection of all slurry lines has to be made every 4 hours during operation ofthe mill. If possible, the inspection should include observation ofthe entire discharge line and discharge spill point into the cell. If "fill to elevation" flags are in place, the tailings and build-up is to be monitored and controlled so as to not cover the flags. 6. Dust Control: Dusting and wind movement of tailings should be noted for Cells 2, 3, 4A, and 4B. Other observations to be noted include a brief description of present weather conditions, and a record of any preci pitation received. Any dusting or wind movement of tailings should be documented. In addition, an estimate should be made for wind speed at the time of the observed dusting or wind movement of tailings. The Radiation Safety Department measures precipitation on a daily basis. Daily measurements should be made as near to 8:00 a.m. as possible every day. Weekend measurements will be taken by the Shifter as close to 8:00 a.m. as possible. All snow or ice should be melted before a reading is taken. 7. Observations of Potential Concern: All observations of concern during the inspection should be noted in this section. Corrective action should follow each area of concern noted. All work orders issued, contacts, or notifications made should be noted in this section as well. It is important to document all these items in order to assure that the tailings management system records are complete and accurate. 8. Map of Tailings Cells: The last section ofthe inspection involves drawing, as accurately as possible, the following items where applicable. N·\C.114BVQllum 2011 SUbmil!a!s Md B.,."i,jon$ for Cg\14D\PMI rIM 01 10 I !IDuna .. MluIl SyOlgn Md PMI MOD rIM Noy 2910 By II, I • BodIID"d!lCl%<i<!lHB\NoYmDbot-IM!mjtJo!!H!!!!l-So';·il!!lf:!l!Mlt\l-4Btfajljn·tMBnt-lj"ICfD1II!IH)M±-Mo.pI~1lHW±t ~l-4BIN<wem~ilHI~Iln!H.!t-GelI4lJl.+tii"fl8I"Mtp!l-S)'!l!<!fIH>ftlH)M-1'-MotH'~~doo White Mesa Mill -Standard Operating Procedures Book I I: Environmental Protection Manual, Section 3. I 1. Cover area 2. Beach/tailing sands area 3. Solution as it exists 4. Pump lines +QII1Gl Revision: DenisonllJ. Page 40 of49 S. Activities around tailings cell (i.e. hauling trash to the dump, liner repairs, etc.) 6. Slurry discharge when operating 7. Over spray system when operating 9. Safety Rules: All safety rules applicable to the mill are applicable when in the tailings area. These rules meet the required MSHA regulations for the tailings area. Please pay particular notice to the following rules: 1. The posted speed limit for the tailings area is IS mph and should not be exceeded. 2. No food or drink is permitted in the area. 3. All personnel entering the tailings area must have access to a two-way radio. 4. Horseplay is not permitted at any time. S. Only those specifically authorized may operate motor vehicles in the restricted area. 6. When road conditions are muddy or slick, a four-wheel drive vehicle is required in the area. 7. Any work performed in which there is a danger of falling or slipping in the cell will require the use of a safety belt or harness with attended life line and an approved life jacket. A portable eyewash must be present on site as well. 8. Anytime the boat is used to perform any work; an approved life jacket and goggles must be worn at all times. There must also be an approved safety watch with a two-way hand- held radio on shore. A portable eyewash must be present on site as well. 10. Preservation of Wildlife: Every effort should be made to prevent wildlife and domesticated animals from entering the tailings area. All wildlife observed should be reported on the Wildlife Report Worksheet during each shift. Waterfowl seen near the tailings cells should be discouraged from landing by the use of noisemakers. 11. Certification: Following the review of this document and on-site instruction on the tailings system inspection program, designated individuals will be certified to perform daily tailings inspections. The Radiation Safety Officer authorizes certification. Refer to the Certification Form, Appendix C. This form should be signed and dated only after a thorough review ofthe tailings information previously presented. The form will then be signed by the Radiation White Mesa Mill -Standard Operating Procedures Book 1 \: Environmental Protection Manual, Section 3.1 Safety Officer and filed. +QI/lGl Revision: Denison I 1,1 Page 41 of49 N\CcU4BVgmIQCY 2QI] Subm!uAls .I]d RomiQD$ Coc CeIl4B\DMT rlnn 0] IQ IIIIaili.", Mgp! Sy510Jn IIld PM! MOl! Plnn No. 2010 By II 1- Bodlin. dgc:N-\GsIl-4B\WgyembcNiuhmillDfHnd..Roy;,.on..ror£t!HffiIadIll8tMIUlHlyOIroHl!Jd.DMtMpn-Jllon-No, 29 I 9 R t II ~~B\N,,""""-Subtn~lJIIt.otId.R;wHI~J..48\~I\f1I-8r<il .... -iIfHI.G~,.pI""~...+kI<!IlMuo While Mesa Mill -tMdard Operating Procedures Dook II: Environmental Protection Mnnual, Section 3.1 APPENDlXC CERTIFICATION FORM Date: __________ _ Name: ________________ ___ ~lIHU Revision: Denison I U . Page 42 of49 I have read the documenllitled 'Tailings Management yslcm, White Mesa Mill Tailings Inspector Training and have received on-sile instruction at the tailings system. Thi instruction included documentation of daily tailings in pections, analysis of potential problems (dike failures, unusual l1ows), notification procedures and saf'ety. ignature I eerlify thallhe above-named person is qualifi.ed to perl'orm the daily inspection of the tailings ystcm at Lhe While Mesa Mill. Radiation afely Personnel! Tailings System upervisor N.IC.U 4!NDDulllY 20] I Subn"IIn1'Md Royjaiool for Cel! groPM], Plan 01 ]0 11\IlIlhn •• MsO) SyOlem and PM! Moo PIQ!! Noy 2010 Ry I I I . Rcdlinq doc?l;lGcl!-48\N_bttSvl>mI!!DIt=nn<H{VI~-tB\-Iol!in .... Mgnl-S:ol"'"1l!]d_PMI_Mon_JIIA.WI~(l.Rrlt ~-i!lI-48\Nuv""'l>et-&bm;lloIs-.nd-l'levioiOM-for.(;.,I~llop_Mllnl~om-tI1I~MtlIH'~~lean,doo White Mesa Mill -Standard Operating I'roccdurcs I100k 11. Environmental PrOlttlion Manual, Section 3.1 ~1I1g1 Itevision: DeniiiOnll.l Page 43 0(49 APPENDIX D FEEDSTOCK STORAGE AREA White Mesa Mill -Standard Operating Procedures Book II: Environmental Protection Manual, Section 3.1 APPENDIXE TABLES +Q IIIGI Revision: Denison I I....!. Page 44 of49 J\~\CcIl4!l1bnunry i ll!! SUbmittoh AlId R .. i"on. for Cl>U4mOMT rilL? OU O J IlTaihnp MIlD! Sworn mel PMT Mon Phut Nux 2010 By I J I - Redlin. d""''I:WcIHB\I'!tmmbtr-Su'''"ittal'·ond-Rffioloo .. rnr£<:!H8ffip~letlH!I!!I-GM'f..M!!!INtNffl9t!!-!W-!+ ~cl!-48\Nov .... bc...submi!~""".·r~1'oiIiH~yftI~l~ White Mesa Mill -Standard Operating Procedures Book II: Environmental Protection Manual, Section 3.1 +QI/IGl Revision: Denisonll.J. Page 45 of49 Table lA Calculated Action leakage Rates for Various head Conditions Cell 4A White mesa Mill Blanding, Utah Head above Liner System (feet) Calculated Action leakage Rate 5 10 15 20 25 30 35 37 ( gallons / acre / day) Table lB Calculated Action leakage Rates for Various head Conditions Cell 4B White mesa Mill Blanding, Utah 222.04 314.01 384.58 444.08 496.50 543.88 587.46 604.01 Head above Liner System (feet) Calculated Action leakage Rate ( gallons / acre / day) 5 211.40 10 317.00 15 369.90 20 422.70 25 475.60 30 528.40 35 570.00 37 581.20 N 'Cell 4B\lonuAry 2011 SubmIUBl .. ndR"Yj.jQnG (0' eRU 18\QMTPIgp OJ JO mUllin •• MaD) SvSle!D ond PM! Moo PhI!! Noy 2010 Ry II I · Rildljn .. d!l<!NJM!HINfflyemberliltbmul!!h-on!HW."'oo .. rot£elH8ffiioo!liS-MJmHilosI..........wMHdl!f!:!llgn-NoyiM!!-l\rl+ ~~eIJ..48'No""",b<t'-Subml""IHrnHl"'~!lI'€e1l4IM'eili~-&yol.~/wR:..p.fon.p~I<1lIHIoG White Mesa Mill-Standard Operating Procedures Book 11: Environmental Protection Manual, Section 3.1 +1l I/IGl Revision: Denisonll.J. Page 46 of49 N lCeO 4BVnDllary ZO! ! Submlll'" lod Br!ljljoDs for CgIl4B\DM! PIM 01 10 IIITwhn .. Msn' Sy51cm Md PM! Moo riM No\' 291Q By II I • RMUDg dooN-¥'idHB\Npy!l!!I!!ft§vblllil!*~' GrIl4Rffiti!,"a-M&n!-I!ytttm-totH».f!:..Mo!H1~y-tt ~W/oY<:m~bmil'JtlHItd.R.,m~lMwlingHwl8l"~ PI~ .. _ White Mesa Mill -Standard Operating Procedures Book II : Environmental Protection Manual, Section 3.1 +..QIIHll Revision: Denison 11.1 Page 47 of 49 Assumptions and Factors: APPENDIXF Example of Freeboard Calculations For Cell4B o Total PMP volume to be stored in Cell 4A -159.4 acre feet o Wave runup factor for Ce1l4A -0.77 feet o Total capacity of Cell 4B -2,094,000 dry tons o Elevation ofFML ofCe1l4B -5,600.35 FMSL o Maximum pool surface area of Cell 4A -40 acres o Total tailings solids deposited into Cell 4B at time beach area first exceeds 5,594 FMSL -1,000,000 dry tons* o Date beach area first exceeds 5,594, FMSL -March 1,2012* o Expected and actual production is as set forth in the following table: Time Period Expected Expected Actual Tailings Tailings Solids Tailings Solids Disposition into Solids Disposition into CeH 4B Disposition Cell 4B Determined at into CeH determined at the beginning of 4B at the end of the the period (dry beginning period (dry tons)* of the tons)* period, multiplied by 150% Safety Factor (dry tons) March 1, 2012 150,000 225,000 225,000 to November 1, 2012 November 1, 300,000 450,000 275,000 2012 to November 1, 2013 November 1, 200,000 300,000 250,000 2013 to November 1, 2014 White Mesa Mill-Standard Operating Procedures Book II: Environmental Protection Manual, Section 3.1 +.QI/IGl Revision: Denisonll..l Page 48 of49 *These expected and actual tailings and production numbers and dates are fictional and have been assumed for illustrative purposes only. Based on these assumptions and factors, the freeboard limits for Ce1l4B would be calculated as follows: 1. Prior to March 1,2012 Prior to March 1,2012, the maximum elevation ofthe beach area in Ce1l4B is less than or equal to 5,594 FMSL, therefore the freeboard limit is set at 5,594.6 FMSL. 2. March 1, 2012 to November 1, 2012 The pool surface area would be reduced to the following amount (1 -225,000 / (2,094,000 -1,000,000)) x 40 acres = 31.77 acres Based on this reduced pool area, the amount offreeboard would be 197.5 acre feet divided by 31.77 acres equals 6.22 feet. When the wave run up factor for Ce1l4B of 0.77 feet is added to this, the total freeboard required is 6.99 feet. This means that the freeboard limit for Cell 4B would be reduced fi'om 5594.6 FMSL to 5592.2 FMSL (5594.6 FMSL minus 6.22 feet, rounded to the nearest one- tenth of a foot). This calculation would be performed at March 1, 2012, and this freeboard limit would persist until November 1,2012. 3. November 1, 2012 to November 1. 2013 The pool surface area would be reduced to the following amount: First, recalculate the pool surface area that should have applied during the previous period, had modeled tonnages (i.e., expected tonnages grossed up by the 150% safety factor) equaled actual tonnages for the period. Since the actual tonnage of225,000 dry tons was the same as the modeled tonnage of 225,000 dry tons, the recalculated pool surface area is the same as the modeled pool surface area for the previous period, which is 31.77 acres. Then, calculate the modeled pool surface area to be used for the period: (1-450,000/ (2,094,000 -1,000,000 -225,000)) x 31.77 acres = 15.32 acres Based on this reduced pool area, the amount offreeboard would be 197.5 acre feet divided by 15.32 acres equals 12.89 feet. When the wave run up factor for Ce1l4B of 0.77 feet is added to this, the total freeboard required is 13.66 feet. This means that the freeboard limit for Cell 4B would be reduced from 5592.2 FMSL to 5586.7 FMSL (5600.35 FMSL minus l3.66 feet, rounded to the nearest one-tenth of a foot). This calculation would be performed at November 1, 2012, and this freeboard limit would persist until November 1, 20l3. H·\C.U 48Voouprv 2011 Suhmjuolund Rpvi.i!!!ll CQ{ c.!I41l\I)MT riM D\ 10 IIIItJl in!t2 Msnl SYllom IDd P M]" Mon Pion NoY 2010 Ry II I - Redlin. docN:\bt!H8\Nomnbrr~Wmilll!!Hn!!-lW'imnrltlf:M!HIII71j!infl.MxnrliY2lmt1l!l!l.DMif.Mort-II!M.,~y-tt ~-tiJ.4~~lin,""tJ.R...n.H.rar...CeI14B'~ailinp-Msn~.j>I~Hl-R~"" White Mesa MiII-Standard Operating Procedures Book 11 : Environmental Protection Manual, Section 3.1 -lQIIHll Revision: Denisonl 1J. Page 49 of49 4. November I, 2013 to November 1. 2014 The pool surface area would be reduced to the following amount: First, recalculate the pool surface area that should have applied during the previous period, had modeled tonnages (i.e., expected tonnages grossed up by the 150% safety factor) equaled actual tonnages for the period. Since modeled tonnages exceeded actual tonnages, the pool area was reduced too much during the previous period, and must be adjusted. The recalculated pool area for the previous period is: (1 -275,000 / (2,094,000 -1,000,000 -225,000) x 31.77 acres = 2l.72 acres. This recalculated pool surface area will be used as the starting point for the freeboard calculation to be performed at November 1,2013. Then, calculate the modeled pool surface area to be used for the period: (1-300,000 / (2,094,000 -1,000,000 -225,000 -275,000)) x 21.72 acres = 10.75 acres Based on this reduced pool area, the amount offreeboard would be 197.5 acre feet divided by 10.75 acres equals 18.37 feet. When the wave run up factor for Ce1l4B of 0.77 feet is added to this, the total freeboard required is 19.14 feet. This means that the freeboard limit for Cell 4B would be reduced from 5586.7 FMSL to 5581.2 FMSL (5600.4 FMSL minus 18.4 feet, rounded to the nearest one-tenth of a foot). This calculation would be performed at November 1,2013, and this freeboard limit would persist until November 1,2014. No)CeU 4BVMllA0' 20\ I Subm!tllII. ond Rcvi,;w fgC C.!I4BIDMI PlIO 01 10 J I1TAdlOQI My!!! SmC!D and OMI Moo rIM NoY 2010 By I! I • Redlin. dQCltf-\lidHll\N;wqnbof.SybmIIIQI~IIlt!Hi!t-G.IHf!\IaWI!!liM!lDt-S~fl'.Mon£lgn:f:l!w-aqIQ-!lrlt ~"""'"4BINOYtttIbof.SubtutllJllHnd.R""'!t0!" (or GeI141M'<!i11~f!llt-Sy5ImHII\d,DM+M_PkwWlo~..Joo White Mesa Mill -Standard Operating Procedures Book II: Environmental Protection Manual, Section 3.1 01111 Revision: Denison 1 1.1 Page 1 of49 WHITE MESA MILL TAILINGS MANAGEMENT SYSTEM AND DISCHARGE MINIMIZATION TECHNOLOGY (DMT) MONITORING PLAN 1. INTRODUCTION This Tailings Management System and Discharge Minimization Technology Monitoring Plan (the "Plan") for the White Mesa Mill (the "Mill") provides procedures for monitoring of the tailings cell system as required under State of Utah Radioactive Materials License No. UT1900479 (the "Radioactive Materials License"), as well as procedures for operating and maintenance of monitoring equipment and reporting procedures that are adequate to demonstrate DMT compliance under State of Utah Ground Water Discharge Permit No. 370004 for the Mill (the "GWDP"). This Plan is designed as a systematic program for constant surveillance and documentation of the integrity of the tailings impoundment system including dike stability, liner integrity, and transport systems, as well as monitoring of water levels in Roberts Pond and feedstock storage areas at the Mill. The Plan requires daily, weekly, quarterly, monthly and annual inspections and evaluations and monthly reporting to Mill management. 2. DAILY TAILINGS INSPECTIONS The following daily tailings inspections shall be performed: 2.1. Daily Comprehensive Tailings Inspection On a daily basis, including weekends, all areas connected with the four tailings cells will be inspected. Observations will be made of the current condition of each cell, noting any corrective action that needs to be taken. The Environmental or Radiation Technician is responsible for performing the daily tailings inspections. The Radiation Safety Officer may designate other individuals with training, as described in Section 2.4 below, to perform the daily tailings inspection. Observations made by the inspector will be recorded on the Daily Inspection Data form (a copy of which is attached in Appendix A). The Daily Inspection Data form contains an inspection checklist, which includes a tailings cells map, and spaces to record observations, especially those of immediate N:\Ce1l4B\January 2011 Submittals and Revisions for CeU4B\DMT Plan Ol.lO.II\Tailings Mgnt System and DMT Mon Plan Nov 2010 Rv 11.1 - clean.doc White Mesa Mill -Standard Operating Procedures Book 11: Environmental Protection Manual, Section 3.1 01/11 Revision: Denison 11.1 Page 2 of49 concern and those requiring corrective action. The inspector will place a check by all inspection items that appear to be operating properly. Those items where conditions of potential concern are observed should be marked with an "X". A note should accompany the "X" specifying what the concern is and what corrective measures will resolve the problem. This observation of concern should be noted on the form until the problem has been remedied. The date that corrective action was taken should be noted as well. Areas to be inspected include the following: CellI, 2,3, 4A and4B, Dikes 1,2,3, 4A-S, 4A-W, 4B- Sand 4B-W wind movement of tailings, effectiveness of dust minimization methods, spray evaporation, Cell 2 spillway, Cell 3 spillway, Cell 3, 4A and 4B liquid pools and associated liquid return equipment, cell leak detection systems, and the wildlife ponds. Operational features of the tailings area are checked for conditions of potential concern. The following items require visual inspection during the daily tailings inspection: a) Tailings slurry and SX raffinate transport systems from the Mill to the active disposal cell(s), and pool return pipeline and pumps. Daily inspections of the tailings lines are required to be performed when the Mill is operating. The lines to be inspected include the: tailings slurry lines from CCD to the active tailings cell; SX raffinate lines that can discharge into CellI, Cell 3, Ce1l4A or Ce1l4B; the pond return line from the tailings area to the Mill; and, lines transporting pond solutions from one cell to another. b) CellI. c) Cell 2. d) Cell 3. e) Ce1l4A. f) Ce1l4B. g) Dike structures including dikes 1,2,3, 4A-S, 4A-W, 4B-S and 4B-W. h) The Cell 2 spillway, Cell 3 spillway, Cell 3, Ce1l4A and Ce1l4B liquid pools and associated liquid return equipment. i) Presence of wildlife and/or domesticated animals in the tailings area, including waterfowl and burrowing animal habitations. N:\CeIl4BVanuary 2011 Submittals and Revisions for CeIl4B\DMT Plan OI.lO.II\Tailings Mgnt System and DMT Mon Plan Nov 2010 Rv 11.1- clean.doc White Mesa Mill -Standard Operating Procedures Book II: Environmental Protection Manual, Section 3.1 j) Spray evaporation pumps and lines. 01 III Revision: Denison ILl Page 3 of49 k) Wind movement of tailings and dust minimization. Wind movement of tailings will be evaluated for conditions which may require initiation of preventative dust minimization measures for cells containing tailings sand. During tailings inspection, general surface conditions will be evaluated for the following: 1) areas of tailings subject to blowing and/or wind movement, 2) liquid pool size, 3) areas not subject to blowing and/or wind movement, expressed as a percentage of the total cell area. The evaluations will be reviewed on a weekly basis, or more frequently if warranted, and will be used to direct dust minimization activities. 1) Observation of flow and operational status ofthe dust control/spray evaporation system(s). m) Observations of any abnormal variations in tailings pond elevations in Cells 1,3, 4A, and 4B. n) Locations of slurry and SX discharge within the active cells. Slurry and SX discharge points need to be indicated on the tailings cells map included in the Daily Inspection Data form. 0) An estimate of flow for active tailings slurry and SX line(s). p) An estimate of flow in the solution return line(s). q) Daily measurements in the leak detection system (LDS) sumps of the tailings cells will be made when warranted by changes in the solution level of the respective leak detection system. The trigger for further action when evaluating the measurements in the CellI and Cell 3 leak detection systems is a gain of more than 12 inches in 24 hours. The solution level in Cell4A or 4B leak detection system is not allowed to be more than 1.0 foot above the lowest point on the bottom flexible membrane liner (Cell 4A FML elevation is 5555.14 amsl and with the addition of the 1.0 foot of solution the solution elevation is 5556.14 feet amsl. For Cell 4B the FML elevation is 5557.50 amsl and with the addition of the 1.0 foot of solution the solution elevation is 5558.50 feet amsl). If any of these observations are made, the Mill Manager should be notified immediately and the leak detection system pump started. In addition, the requirement to notify the Executive Secretary in accordance with Parts I.D.6 and I.G.3 ofthe Groundwater Discharge Permit must N:\Ce1l4BVanuary 2011 Submittals and Revisions for CeIl4B\DMT Plan Ol.lO.II\Tailings Mgnt System and DMT Mon Plan Nov 2010 Rv 11.1 - clean.doc White Mesa MiIl-Standard Operating Procedures Book II: Environmental Protection Manual, Section 3.1 01111 Revision: Denison Il.l Page 4 of49 be adhered to when the solution level trigger for Cell 4A or 4B has been exceeded. Whenever the leak detection system pump is operating and the flow meter totalizer is recording, a notation of the date and the time will be recorded on the Daily Inspection Data form. This data will be used in accordance with License Condition 11.3.B through II.3.E of the Mill's Radioactive Materials License, to determine whether or not the flow rate into the leak detection system is in excess of the License Conditions. r) An estimate ofthe percentage of the tailings beach surface area and solution pool area is made, including estimates of solutions, cover areas, and tailings sands for Cells 3, 4A and 4B. Items (a), (m), (n), and (0) are to be done only when the Mill is operating. When the Mill is down, these items cannot be performed. 2.2. Daily Operations Inspection During Mill operation, the Shift Foreman, or other person with the training specified in Section 2.4 below, designated by the Radiation Safety Officer, will perform an inspection of the tailings line and tailings area at least once per shift, paying close attention for potential leaks and to the discharges from the pipelines. Observations by the Inspector will be recorded on the appropriate line on the Operating Foreman's Daily Inspection form. 2.3. Daily Operations Patrol In addition to the inspections described in Sections 2.1 and 2.2 above, a Mill employee will patrol the tailings area at least twice per shift during Mill operations to ensure that there are no obvioussafety or operational issues, such as leaking pipes or unusual wildlife activity or incidences. No record ofthese patrols need be made, but the inspectors will notify the Radiation Safety Officer and/or Mill management in the event that during their inspection they discover that an abnormal condition or tailings emergency has occurred. 2.4. Training All individuals performing inspections described in Sections 2.1 and 2.2 above must have Tailings Management System training as set out in the Tailings Inspection Training procedure, which is attached as Appendix B. This training will include a training pack explaining the procedure for performing the inspection and addressing inspection items to be observed. In addition, each individual, after reviewing the training pack, will sign a certification form, indicating that training N:\Cell 4BVanuary 2011 Submittals and Revisions for Cell 4B\DMT Plan Ol.lO.ll\Tailings Mgnt System and DMT Mon Plan Nov 2010 Rv 11.1 - clean.doc White Mesa Mill -Standard Operating Procedures Book ll: Environmental Protection Manual, Section 3.1 has been received relative to his/her duties as an inspector. 2.5. Tailings Emergencies 01111 Revision: Denison 11.1 Page 5 of49 Inspectors will notify the Radiation Safety Officer and/or Mill management immediately if, during their inspection, they discover that an abnormal condition exists or an event has occurred that could cause a tailings emergency. Until relieved by the Environmental or Radiation Technician or Radiation Safety Officer, inspectors will have the authority to direct resources during tailings emergencIes. Any major catastrophic events or conditions pertaining to the tailings area should be reported immediately to the Mill Manager or the Radiation Safety Officer, one of whom will notify Corporate Management. If dam failure occurs, notify your supervisor and the Mill Manager immediately. The Mill Manager will then notify Corporate Management, MSHA (303-231-5465), and the State of Utah, Division of Dam Safety (801-538-7200). 3. WEEKLY TAILINGS AND DMT INSPECTION 3.1. Weekly Tailings Inspections Weekly tailings inspections are to be conducted by the Radiation Safety Department and include the following: a) Leak Detection Systems Each tailings cell's leak detection system shall be checked weekly to determine whether it is wet or dry. If marked wet, the liquid levels need to be measured and reported. In Cell 1 and Cell 3 the leak detection system is measured by use of a pipe that is removed from the system which will indicate the presence of solutions in the LDS system. The Cell 4A and 4B leak detection systems are monitored on a continuous basis by use of a pressure transducer that feeds water level information to an electronic data collector. The pressure transducer is calibrated for fluid with a specific gravity of 1.0. The water levels are measured every hour and the information is stored for later retrieval. The water levels are measured to the nearest 0.10 inch. The data collector is currently programmed to store 7 days of water level information. The number of days of stored data can be increased beyond 7 days if needed. The water level data is downloaded to a laptop computer on a weekly basis and incorporated into the Mill's environmental monitoring data base, and into the files for weekly inspection reports of the tailings cell leak detection systems N:\Ce1l4BVanual)' 2011 Submittals and Revisions for Ce1l4B\DMT Plan 01.10. 1 llTailings Mgnt System and DMT Mon Plan Nov 2010 Rv 11.1 - clean.doc White Mesa Mill-Standard Operating Procedures Book 11: Environmental Protection Manual, Section 3.1 01 III Revision: Denison 11.1 Page 6 of49 If sufficient fluid is present in the leak detection system of any cell, the fluid shall be pumped from the LDS, to the extent reasonably possible, and record the volume of fluid recovered. Any fluid pumped from an LDS shall be returned to a disposal cell. If fluid is pumped from an LDS, the flow rate shall be calculated by dividing the recorded volume of fluid recovered by the elapsed time since fluid was last pumped or increases in the LDS fluid levels were recorded, whichever is the more recent. This calculation shall be documented as part of the weekly inspection. Upon the initial pumping of fluid from an LDS, a fluid sample shall be collected and analyzed in accordance with paragraph 11.3 C. of the Radioactive Materials License. For Cell4A and 4B, under no circumstance shall fluid head in the leak detection system sump exceed a 1-foot level above the lowest point in the lower flexible membrane liner. To determine the Maximum Allowable Daily LDS Flow Rates in the Ce1l4A and 4B leak detection systems, the total volume of all fluids pumped from the LDS on a weekly basis shall be recovered from the data collector, and that information will be used to calculate an average volume pumped per day. Under no circumstances shall the daily LDS flow volume exceed 24,160 gallons/day for Ce1l4A or 26, 145gallons/day for Ce1l4B. The maximum daily LDS flow volume will be compared against the measured cell solution levels detailed on Table 1A and IB (for Cells 4A and 4B, respectively) in Appendix E, to determine the maximum daily allowable LDS flow volume for varying head conditions in Cell4A and 4B. b) Slimes Drain Water Level Monitoring (i) Cell 3 is nearly full and will commence closure when filled. Cell 2 is partially reclaimed with the surface covered by platform fill. Each cell has a slimes drain system which aids in dewatering the slimes and sands placed in the cell; (ii) Cell 2 has a pump placed inside of the slimes drain access pipe at the bottom of the slimes drain. As taken from actual measurements, the bottom of the slimes drain is 38 feet below a water level measuring point at the centerline of the slimes drain access pipe, at the ground surface level. This means that the bottom of the slimes drain pool and the location of the pump are one foot above the lowest point of the N:\Cell 4BVanual)' 2011 Submittals and Revisions for Cell 4B\DMT Plan OI.ID.II\Tailings Mgnt System and DMT Mon Plan Nov 2010 Rv 11.1 • clean.doc White Mesa Mill -Standard Operating Procedures Book I I: Environmental Protection Manual, Section 3.1 01 II I Revision: Denison I 1.I Page 7 of49 FML in Cell 2, which, based on construction reports, is at a depth of 39 feet below the water level measuring point on the slimes drain access pipe for Cell 2; (iii)The slimes drain pump in Cell 2 is activated and deactivated by a float mechanism and water level probe system. When the water level reaches the level of the float mechanism the pump is activated. Pumping then occurs until the water level reaches the lower probe which turns the pump off. The lower probe is located one foot above the bottom of the slimes drain standpipe, and the float valve is located at five feet above the bottom of the slimes drain standpipe. The average wastewater head in the Cell 2 slimes drain is therefore less than 5 feet and is below the phreatic surface of tailings Cell 2, about 20 feet below the water level measuring point on the slimes drain access pipe. As a result, there is a continuous flow of wastewater from Cell 2 into the slimes drain collection system. Mill management considers that the average allowable wastewater head in the Cell 2 slimes drain resulting from pumping in this manner is satisfactory and is as low as reasonably achievable. (iv)The Cell 2 slimes drain pump is checked weekly to observe that it is operating and that the water level probe and float mechanism are working properly, which is noted on the Weekly Tailings Inspection Form. If at any time the pump is observed to be not working properly, it will be fixed or replaced within 15 days; (v) Depth to wastewater in the Cell 2 slimes drain access pipe shall be monitored and recorded weekly to determine maximum and minimum fluid head before and after a pumping cycle, respectively. All head measurements must be made from the same measuring point (the notch at the north side of the access pipe), and made to the nearest 0.01 foot. The results will be recorded as depth-in-pipe measurements on the Weekly Tailings Inspection Form; (vi)On a monthly basis, the slimes drain pump will be turned off and the wastewater in the slimes drain access pipe will be allowed to stabilize for at least 90 hours. Once the water level has stabilized (based on no change in water level for three (3) successive readings taken no less than one (1) hour apart) the water level of the wastewater will be measured and recorded as a depth-in-pipe measurement on the Monthly Inspection Data form, by measuring the depth to water below the water level measuring point on the slimes drain access pipe; (vii) No process liquids shall be allowed to be discharged into Cell 2; (viii) If at any time the most recent average annual head in the Cell 2 slimes drain is found to have increased above the average head for the previous calendar year, the Licensee will comply with the requirements of Part I.G.3 of the GWDP, including the requirement to provide notification to the Executive Secretary orally within 24 hours followed by written notification; (ix)Because Cell 3 and Ce1l4A are currently active, no pumping from the Cell 3 or Cell 4A slimes drain is authorized. No pumping from the Ce1l4B slimes drain will be authorized once it is put into service and while it is active. Prior to initiation of tailings dewatering operations for Cell 3, Cell 4A, or Cell 4B, a similar procedure will be developed for ensuring that average head elevations in the Cell 3 and Ce1l4A N:ICell4BVanuary 2011 Submittals and Revisions for Ce114BIDMT Plan 01.IO.IIITailings Mgnt System and DMT Mon Plan Nov 2010 Rv 11 .1 - clean.doc White Mesa Mill -Standard Operating Procedures Book II: Environmental Protection Manual, Section 3.1 01111 Revision: Denison11.1 Page 8 of49 slimes drains are kept as low as reasonably achievable, and that the Cell 3, Cell4A, and Cell 4 slimes drains are inspected and the results reported in accordance with the requirements of the permit." c) Wind Movement a/Tailings An evaluation of wind movement of tailings or dusting and control measures shall be taken if needed. d) Tailings Wastewater Pool Elevation Monitoring Solution elevation measurements in Cells 14A, and 4B and Roberts Pond are to be taken by survey on a weekly basis, and the beach area in Cell 4A and 4B with the maximum elevation is to be taken by survey on a monthly basis, as follows: (i) The survey will be performed by the Mill's Radiation Safety Officer or designee (the "Surveyor") with the assistance of another Mill worker (the "Assistant"); (ii) The survey will be performed using a survey instrument (the "Survey Instrument") accurate to 0.01 feet, such as a Sokkai No. B21, or equivalent, together with a survey rod (the "Survey Rod") having a visible scale in 0.01 foot increments; (iii)The reference Points (the "Reference Points") for Cells 14A, and 4B, and Roberts Pond are known points established by professional survey. For CellI and Roberts Pond, the Reference Point is a wooden stake with a metal disk on it located on the southeast comer of Cell 1. The elevation of the metal disk (the "Reference Point Elevation") for Cell 1 and Roberts Pond is at 5,623.14 feet above mean sea level ("FMSL"). For Cell 3 CeIl4A, and CeIl4B, the Reference Point is a piece of metal rebar located on the south dike of Cell 3. The elevation at the top of this piece ofrebar (the Reference Point Elevation for Cell4A and 4B) is at 5,607.83 FMSL. The Surveyor will set up the Survey Instrument in a location where both the applicable Reference Point and pond surface are visible. For Cell 1 and Roberts Pond, this is typically on the road on the Cell 1 south dike between Cell 1 and Roberts Pond, approximately 100 feet east of the CellI/Roberts Pond Reference Point. For Cell4A and Cell4B, this is typically on the road on the Cell 3 dike approximately 100 feet east of the Cell 3 Reference Point; (iv)Once in location, the Surveyor will ensure that the Survey Instrument is level by centering the bubble in the level gauge on the Survey Instrument; (v) The Assistant will place the Survey Rod vertically on the Reference Point (on the metal disk on the CellI/Roberts Pond Reference Point on the top of the rebar on the Cell4A and 4B Reference Point. The Assistant will ensure that the Survey Rod is vertical by gently rocking the rod back and forth until the Surveyor has established a level reading; N:\Ce1l4BVanuary 2011 Submittals and Revisions for Ce1l4B\DMT Plan OLlO.II\Tailings Mgnt System and DMT Mon Plan Nov 2010 Rv ILl - clean.doc White Mesa Mill-Standard Operating Procedures Book 11: Environmental Protection Manual, Section 3.1 01111 Revision: Denisonll.1 Page 9 of49 (vi) The Surveyor will focus the cross hairs of the Survey Instrument on the scale on the Survey Rod, and record the number (the "Reference Point Reading"), which represents the number of feet the Survey Instrument is reading above the Reference Point; (vii) The Assistant will then move to a designated location where the Survey Rod can be placed on the surface of the main solution pond in the CellI, CeIl4A, CeIl4B, or Roberts Pond, or the area ofthe beach in Cell 4A or Cell 4B with the highest elevation, as the case may be. These designated locations, and the methods to be used by the Assistant to consistently use the same locations are as follows: A. Pond Surface Measurements I. Cell4A The Assistant will walk down the slope in the northeast comer of Cell 4A and place the Survey Rod at the liquid level. II. Cell4B The Assistant will walk down the slope in the northwest comer of Cell4B and place the Survey Rod at the liquid level. III. Cell 1 A mark has been painted on the north side of the ramp going to the pump platform in Cell 1. The Assistant will place the Survey Rod against that mark and hold the rod vertically, with one end just touching the liquid surface; and IV Roberts Pond A mark has been painted on the railing of the pump stand in Roberts Pond. The Assistant will place the Survey Rod against that mark and hold the rod vertically, with one end just touching the liquid surface. Based on the foregoing methods, the approximate coordinate locations for the measuring points for Roberts Pond and the Cells are: Northing Easting Roberts Pond 323,041 2,579,697 CellI 322,196 2,579,277 Ce1l4A 320,300 2,579,360 Ce1l4B 320,690 2,576,200 N:\CeIl4BIJanuary 20 II Submittals and Revisions for Cell 4B\DMT Plan 01.10.11 \Tailings Mgnt System and DMT Mon Plan Nov 2010 Rv 11.1 - clean.doc White Mesa Mill -Standard Operating Procedures Book 11: Environmental Protection Manual, Section 3.1 01/11 Revision: Denison11.1 Page 10 of49 B. These coordinate locations may vary somewhat depending on solution elevations in the Pond and Cells; Cell 4 B Beach Elevation The Assistant will place the Survey Rod at the point on the beach area ofCe1l4B that has the highest elevation. If it is not clear which area of the beach has the highest elevation, then multiple points on the beach area will be surveyed until the Surveyor is satisfied that the point on the Cell4B beach area with the highest elevation has been surveyed. If it is clear that all points on the Ce1l4B beach area are below 5,593 FMSL, then the Surveyor may rely on one survey point; (viii) The Assistant will hold the Survey Rod vertically with one end of the Survey Rod just touching the pond surface. The Assistant will ensure that the Survey Rod is vertical by gently rocking the rod back and forth until the Surveyor has established a level reading; (ix)The Surveyor will focus the cross hairs of the Survey Instrument on the scale on the Survey Rod, and record the number (the "Pond Surface Reading"), which represents the number of feet the Survey Instrument is reading above the pond surface level. The Surveyor will calculate the elevation of the pond surface as FSML by adding the Reference Point Reading for the Cell or Roberts Pond, as the case may be, to the Reference Point Elevation for the Cell or Roberts Pond and subtracting the Pond Surface Reading for the Cell or Roberts Pond, and will record the number accurate to 0.01 feet. e) Decontamination Pads (i) New Decontamination Pad The New Decontamination Pad is located in the southeast corner of the ore pad, near the Mill's scale house. A. In order to ensure that the pnmary containment of the New Decontamination Pad water collection system has not been compromised, and to provide an inspection capability to detect leakage from the primary containment, vertical inspection portals have been installed between the primary and secondary containments; B. These portals will be visually observed on a weekly basis as a means of detecting any leakage from the primary containment into the void N :\CelJ 4BVanuary 2011 Submittals and Revisions for Cell 4B\DMT Plan 01.10.11 \Tailings Mgnt System and DMT Mon Plan Nov 20 I 0 Rv 11.1 - clean.doc White Mesa Mill -Standard Operating Procedures Book 11: Environmental Protection Manual, Section 3.1 01111 Revision: Denison 11.1 Page 11 of49 between the primary and secondary containment. The depth to water in each portal will be measured weekly, by physically measuring the depth to water with an electrical sounding tape/device. All measurements must be made from the same measuring point and be made to the nearest 0.01 foot; C. These inspections will be recorded on the Weekly Tailings Inspection form; D. The water level shall not exceed 0.10 foot above the concrete floor in any standpipe, at any time. This will be determined by subtracting the weekly depth to water measurement from the distance from the measuring point in the standpipe to the dry concrete floor The depth to water from the top (elevation 5589.8 feet amsl) of any of the three (3) observation ports to the standing water shall be no less than 6.2 feet. Depths less than 6.2 feet shall indicate more that 0.1 foot of standing water above the concrete floor (elev. 5583.5 feet amsl), and shall indicate a leak in the primary containment. E. Any observation of fluid between the primary and secondary containments will be reported to the Radiation Safety Officer (RSO). F In addition to inspection of the water levels in the standpipes, the New Decontamination Pad, including the concrete integrity of the exposed surfaces of the pad, will be inspected on a weekly basis. Any soil and debris will be removed from the New Decontamination Pad immediately prior to inspection of the concrete wash pad for cracking. Observations will be made of the current condition of the New Decontamination Pad. Any abnormalities relating to the pad and any damage to the concrete wash surface of the pad will be noted on the Weekly Tailings Inspection form. If there are any cracks greater than 1/8 inch separation (width), the RSO must be contacted. The RSO will have the responsibility to cease activities and have the cracks repaired. (U) Existing Decontamination Pad The Existing Decontamination Pad is located between the northwest comer ofthe Mill's maintenance shop and the ore feeding grizzly. A. The Existing Decontamination Pad will be inspected on a weekly N:\CeIl4BlJanuary 2011 Submittals and Revisions for CeIl4B\DMT Plan 01.10.II\Tailings Mgnt System and DMT Man Plan Nov 2010 Rv 11.1 - clean. doc White Mesa MiIl-Standard Operating Procedures Book II: Environmental Protection Manual, Section 3.1 01111 Revision: Denison 11.1 Page 12 of 49 j) Summary basis. Any soil and debris will be removed from the Existing Decontamination Pad immediately prior to inspection ofthe concrete wash pad for cracking Observations will be made of the current condition of the Existing Decontamination Pad, including the concrete integrity of the exposed surfaces of the pad. Any abnormalities relating to the pad and any damage or cracks on the concrete wash surface of the pad will be noted on the Weekly Tailings Inspection form. Ifthere are any cracks greater than 118 inch separation (width), the RSO must be contacted. The RSO will have the responsibility to cease activities and have the cracks repaired. In addition, the weekly inspection should summarize all activities concerning the tailings area for that particular week. Results ofthe weekly tailings inspection are recorded on the Weekly Tailings and DMT Inspection form. An example of the Weekly Tailings and DMT Inspection form is provided in Appendix A. 3.2. Weekly Inspection of Solution Levels in Roberts Pond On a weekly basis, solution elevations are taken on Roberts Pond, in accordance with the procedures set out in Section 3.1 d) above. The Weekly solution level in Roberts Pond is recorded on the Weekly Tailings and DMT Inspection form. Based on historical observations, the FML at the Pond Surface Reading area for Roberts Pond, is approximately six inches above the lowest point on the pond's FML. If the pond solution elevation at the Pond Surface Reading area is at or below the FML for that area, the pond will be recorded as being dry. 3.3. Weekly Feedstock Storage Area Inspections Weekly feedstock storage area inspections will be performed by the Radiation Safety Department to confirm that: a) the bulk feedstock materials are stored and maintained within the defined area described in the GWDP, as indicated on the map attached hereto as Appendix D; b) a 4 ft. buffer is maintained at the periphery of the storage area which is absent bulk material in order to assure that the materials do not encroach upon the boundary ofthe storage area; and c) all alternate feedstock located outside the defined Feedstock Area are maintained within water tight containers. N:\CeIl4BVanuary 2011 Submittals and Revisions for CeIl4B\DMT Plan 01.10.l1\Tailings Mgnt System and DMT Mon Plan Nov 2010 Rv 11.1 - clean.doc White Mesa Mill -Standard Operating Procedures Book 11: Environmental Protection Manual, Section 3.1 01111 Revision: Denison 1l.1 Page 13 of49 The results of this inspection will be recorded on the Ore Storage/Sample Plant Weekly Inspection Report, a copy of which is contained in Appendix A. Any variance in stored materials from this requirement or observed leaking alternate feedstock drums or other containers will be brought to the attention of Mill Management and rectified within 15 days. 4. MONTHL Y TAILINGS INSPECTION Monthly tailings inspections will be performed by the Radiation Safety Officer or his designee from the Radiation Safety Department and recorded on the Monthly Inspection Data form, an example of which is contained in Appendix A. Monthly inspections are to be performed no sooner than 14 days since the last monthly tailings inspection and can be conducted concurrently with the quarterly tailings inspection when applicable. The following items are to be inspected: a) Tailings Slurry Pipeline When the Mill is operating, the slurry pipeline will be inspected at key locations to determine pipe wear. Pipe thickness will be measured using an ultrasonic device by either the radiation safety staff or other trained designees. The critical points of the pipe include bends, slope changes, valves, and junctions, which are critical to dike stability. These locations to be monitored will be determined by the Radiation Safety Officer or his designee from the Radiation Safety Department during the Mill run. b) Diversion Ditches Diversion ditches 1, 2 and 3 shall be monitored monthly for sloughing, erosion, undesirable vegetation, and obstruction of flow. Diversion berm 2 should be checked for stability and signs of distress. c) Sedimentation Pond Activities around the Mill and facilities area sedimentation pond shall be summarized for the month. d) Overspray Dust Minimization The inspection shall include an evaluation of overspray minimization, if applicable. This entails ensuring that the overspray system is functioning properly. In the event that overspray is carried more than 50 feet from the cell, the overspray system should be immediately shut-off. N:\CeU4B\January 201 J Submittals and Revisions for Ce1l4B\DMT Plan 01.10. J I\Tailings Mgnt System and DMT Mon Plan Nov 2010 Rv 11.1 - clean. doc White Mesa Mill -Standard Operating Procedures Book I J: Environmental Protection Manual, Section 3.1 e) Remarks 01111 Revision: Denisonll.l Page 14 of49 A section is included on the Monthly Inspection Data form for remarks in which recommendations can be made or observations of concern can be documented. j) Summary of Daily, Weekly and Quarterly Inspections The monthly inspection will also summarize the daily, weekly and, if applicable, quarterly tailings inspections for the specific month. In addition, settlement monitors are typically surveyed monthly and the results reported on the Monthly Inspection Data form. 5. QUARTERLY TAILINGS INSPECTION The quarterly tailings inspection is performed by the Radiation Safety Officer or his designee from the Radiation Safety Department, having the training specified in Section 2.4 above, once per calendar quarter. A quarterly inspection should be performed no sooner than 45 days since the previous quarterly inspection was performed. Each quarterly inspection shall include an Embankment Inspection, an Operations/Maintenance Review, a Construction Review and a Summary, as follows: a) Embankment Inspection The Embankment inspection involves a visual inspection of the crest, slope and toe of each dike for movement, seepage, severe erosion, subsidence, shrinkage cracks, and exposed liner. b) Operations/Maintenance Review The Operations/Maintenance Review consists of reviewing Operations and Maintenance activities pertaining to the tailings area on a quarterly basis. c) Construction Review The Construction Review consists of reviewing any construction changes or modifications made to the tailings area on a quarterly basis. N:\Ce1l4BlJanuary 2011 Submittals and Revisions for CeU4B\DMT Plan Ol.lO.II\Tailings Mgnt System and DMT Mon Plan Nov 2010 Rv 11.1 - clean.doc White Mesa Mill -Standard Operating Procedures Book II: Environmental Protection Manual, Section 3.1 d) Summary 01 /11 Revision: Denisonll.l Page 15 of 49 The summary will include all major activities or observations noted around the tailings area on a quarterly basis. If any of these conditions are noted, the conditions and corrective measures taken should be documented in the Quarterly Inspection Data form. An example of the Quarterly Inspection Data form is provided in Appendix A. 6. ANNUAL EVALUATIONS The following annual evaluations shall be performed: 6.1. Annual Technical Evaluation An annual technical evaluation of the tailings management system is performed by a registered professional engineer (PE), who has experience and training in the area of geotechnical aspects of retention structures. The technical evaluation includes an on-site inspection of the tailings management system and a thorough review of all tailings records for the past year. The Technical Evaluation also includes a review and summary of the annual movement monitor survey (see Section 5.2 below). All tailings cells and corresponding dikes will be inspected for signs of erosion, subsidence, shrinkage, and seepage. The drainage ditches will be inspected to evaluate surface water control structures. In the event tailings capacity evaluations (as per SOP PBL-3) were performed for the receipt of alternate feed material during the year, the capacity evaluation forms and associated calculation sheets will be reviewed to ensure that the maximum tailings capacity estimate is accurate. The amount of tailings added to the system since the last evaluation will also be calculated to determine the estimated capacity at the time of the evaluation. Tailings inspection records will consist of daily, weekly, monthly, and quarterly tailings inspections. These inspection records will be evaluated to determine if any freeboard limits are being approached. Records will also be reviewed to summarize observations of potential concern. The evaluation also involves discussion with the Environmental and/or Radiation Technician and the Radiation Safety Officer regarding activities around the tailings area for the past year. During the annual inspection, photographs ofthe tailings area will be taken. The training ofindividuals will be reviewed as a part of the Annual Technical Evaluation. N:\CclI 4BVanuary 2011 Submittals and Revisions for Ce1l4B\DMT Plan 01.10.ll\Tailings Mgnt System and DMT Man Plan Nov 2010 Rv 11.1 - clean. doc White Mesa Mill -Standard Operating Procedures Book 11: Environmental Protection Manual, Section 3.1 01/11 Revision: Denisonll.l Page 16 of49 The registered engineer will obtain copies of selected tailings inspections, along with the monthly and quarterly summaries of observations of concern and the corrective actions taken. These copies will then be included in the Annual Technical Evaluation Report. The Annual Technical Evaluation Report must be submitted by November 15th of every year to: Directing Dam Safety Engineer State of Utah, Natural Resources 1636 West North Temple, Suite 220 Salt Lake City, Utah 84116-3156 6.2. Movement Monitors A movement monitor survey is to be conducted by a licensed surveyor annually during the second quarter of each year. The movement monitor survey consists of surveying monitors along dikes 3-S, 4A-W, and 4A-S to detect any possible settlement or movement of the dikes. The data generated from this survey is reviewed and incorporated into the Annual Technical Evaluation Report ofthe tailings management system. 6.3. Freeboard Limits The freeboard limits set out in this Section are intended to capture the Local 6-hour Probable Maximum Precipitation (PMP) event, which was determined in the January 10, 1990 Drainage Report (the "Drainage Report") for the White Mesa site to be 10 inches. The flood volume from the PMP event over the Cell 1 pond area plus the adjacent drainage areas, was calculated in the Drainage Report to be 103 acre feet of water, with a wave run up factor of 0.90 feet. The flood volume from the PMP event over the Cell 2 and Cell 3 pond areas, plus the adjacent drainage areas was calculated in the Drainage Report to be 123.4 acre-feet of water. The flood volume from the PMP event over the Cell4A area was calculated in the Drainage Report to be 36 acre-feet of water (40 acres, plus the adjacent drainage area of 3.25 acres), times the PMP of 10 inches), with a wave run up factor of 0.77 feet. The flood volume from the PMP event over the Cell 4B area has been calculated to be 38.1 acre- feet of water (40 acres, plus the adjacent drainage area of 5.72 acres), times the PMP of 10 inches, with a wave run up factor of 0.77 feet. The total pool surface area in Celli is 52.9 acres, in Cell4A is 40 acres, and in Ce1l4B is 40 acres. The top of the flexible membrane liner ("FML") for Celli is 5,618.2 FMSL, for Cell4A N:\CeIl4BVanuary 2011 Submittals and Revisions for Ce1l4B\DMT Plan 01.10.II\Tailings Mgnt System and DMT Mon Plan Nov 2010 Rv 11.1 - clean.doc White Mesa Mill-Standard Operating Procedures Book 11: Environmental Protection Manual, Section 3.1 is 5,598.5 FMSL and for Cell4B is 5600.4 FMSL. o III 1 Revision: Denison 11.1 Page 17 of49 Based on the foregoing, the freeboard limits for the Mill's tailings cells will be set as follows: 6.3.1. Celli The freeboard limit for Cell 1 will be set at 5,615.4 FMSL. This will allow CellI to capture all of the PMP volume associated with Cell 1. The total volume requirement for Cell 1 is 103 acre feet divided by 52.9 acres equals 1.95 feet, plus the wave run up factor of 0.90 feet equals 2.85 feet. The freeboard limit is then 5,618.2 FMSL minus 2.85 feet equals 5,615.4 FMSL. Under Radioactive Materials License condition 10.3, this freeboard limit is set and is not recalculated annually. 6.3.2. Cell 2 The freeboard limit for Cell 2 is inapplicable, since Cell 2 is filled with solids. All of the PMP volume associated with Cell 2 will be attributed to Cell4A (and/or any future tailings cells). 6.3.3. Cell 3 The freeboard limit for Cell 3 is inapplicable, since Cell 3 is close to being filled with solids, and all of the PMP flood volume associated with Cell 3 will be attributed to Cell 4B (and/or any future tailings cells). 6.3.4. Cell4A The freeboard limit for Cell4A is inapplicable since all of the PMP flood volume associated with Cell4A will be attributed to Ce1l4B. A spillway has been added to Ce1l4A to allow overflow into CeIl4B. 6.3.5. Cell4B The freeboard limit for Cell4B will be set assuming that the total PMP volume for Cells 2, 3, 4A, and 4B of 159.4 acre feet will be accommodated in Cell 4B. The procedure for calculating the freeboard limit for Cell 4B is as follows: (aJ When the Pool Surface Area is 40 Acres When the pool surface area in Cell4B is 40 acres (i.e., when there are no beaches), the freeboard limit for Cell4B will be 5,594.6FMSL, which is 5.7 feet below the FML. This freeboard value was developed as follows: PMP Flood Volume Overflow from Cell4A assuming no storage in Cell 3 or 4A Sum of PMP volume and overflow volume 38.1 acre-feet 159.4 acre-feet 197.5 acre-feet N:\CeIl4B\January 2011 Submittals and Revisions for CeIl4B\DMT Plan Ol.lO.II\Tailings Mgnt System and DMT Mon Plan Nov 2010 Rv 11.1 - clean.doc White Mesa Mill -Standard Operating Procedures Book II: Environmental Protection Manual, Section 3.1 Depth to store PMP an overflow volume = 197.5 acre-feet/40 acres Wave run up factor Total required freeboard 01/11 Revision: DenisonIl.l Page 18 of49 4.9 feet 0.77 feet 5.7 feet (all values in the above calculation have been rounded to the nearest one-tenth of afoot); (b) When the Maximum Elevation of the Beach Area is 5,594 FMSL or Less When the maximum elevation ofthe beach area in Cell4B is 5594 FMSL or less, then the freeboard limit will be 5,594.6 FMSL, which is the same as in (a) above. This allows for the situation where there may be beaches, but these beaches are at a lower elevation than the freeboard limit established in (a) above, and there is therefore ample freeboard above the beaches to hold the maximum PMP volume. The maximum elevation of the beach area will be determined by monthly surveys performed by Mill personnel in accordance with the Mill's DMT Plan. (c) When the Maximum Elevation of the Beach Area First Exceeds 5,594 FMSL When the maximum elevation of the beach area in Cell 4B first exceeds 5,594 FMSL, then the freeboard limit for the remainder of the ensuing year (period t=O) (until the next November 1) will be calculated when that elevation is first exceeded (the "Initial Calculation Date"), as follows: i) The total number of dry tons of tailings that have historically been deposited into Cell 4B prior to the Initial Calculation Date ("To") will be determined; ii) The expected number of dry tons to be deposited into Cell4B for the remainder of the ensuing year (up to the next November 1), based on production estimates for that period ("L1o*"), will be determined; iii) L10* will be grossed up by a safety factor of 150% to allow for a potential underestimation of the number of tons that will be deposited in the cell during the remainder of the ensuing year. This grossed up number can be referred to as the "modeled tonnage" for the period; iv) The total design tailings solid storage capacity of Cell 4A will be accepted as 2,094,000 dry tons of tailings; v) The available remaining space in Cell4B for solids as at the Initial Calculation Date will be calculated as 2,094,000 dry tons minus To; vi) The reduction in the pool surface area for the remainder ofthe ensuing year will be assumed to be directly proportional to the reduction in the available space in Ce1l4A for solids. That is, the reduced pool surface area for period t=O ("RP Ao"), after the reduction, will be calculated to be: (1-(L10* x 1.5) 1(2,094,000 -To» x 40 acres = RPAo vii) The required freeboard for Cell 4A for the remainder of the period t=O can be calculated in feet to be the wave run up factor for Cell 4B of 0.77 feet plus the quotient of 197.5 acre feet divided by the RP Ao. The freeboard limit for Cell4B for the remainder of period t=O would then be the elevation of the FML for Ce1l4B of N:\CeIl4BVanuary 2011 Submittals and Revisions for Ce114B\DMT Plan 01.10.II\Tailings Mgnt System and DMT Mon Plan Nov 2010 Rv 11.1 - clean. doc White Mesa Mill-Standard Operating Procedures Book 11: Environmental Protection Manual, Section 3.1 01/11 Revision: Denisonl1.1 Page 19 of49 5594.0 FMSL less this required freeboard amount, rounded to the nearest one-tenth of a foot; and viii) The foregoing calculations will be performed at the Initial Calculation Date and the resulting freeboard limit will persist until the next November 1. An example of this calculation is set out in Appendix F. (d) Annual Freeboard Calculation When the Maximum Elevation of the Beach Area Exceeds 5,594 FMSL On November 1 of each year (the "Annual Calculation Date"), the reduction in pool area for the ensuing year (referred to as period t) will be calculated by: i) First, calculating the Adjusted Reduced Pool Area for the previous period (ARP At-I) to reflect actual tonnages deposited in Cell4B for the previous period (period t-1). The RP At-I used for the previous period was based on expected tonnages for period t- 1, grossed up by a safety factor. The ARPAt_1 is merely the RPA that would have been used for period t-1 had the actual tonnages for year t-1 been known at the outset of period t -1 and had the RP A been calculated based on the actual tonnages for period t-1. This allows the freeboard calculations to be corrected each year to take into account actual tonnages deposited in the cell as of the date of the calculation. The ARPAt_1 can be calculated using the following formula: (l-llt-I / (2,094,000 - Tt-I)) X ARPAt_2 = ARPAt_1 Where: • llt-I is the actual number of dry tons of tailings solids deposited in Cell 4B during period t-1; • Tt-I is the actual number of dry tons oftailings solids historically deposited in Cell4B prior to the beginning of period t-1; and • ARP At-2 is the Adjusted Reduced Pool Area for period t-2. If period t-2 started at the Initial Calculation Date, then ARP At-2 is 40 acres; ii) Once the ARP At-I for the previous period (period t-1) has been calculated, the RP A for the subject period (period t) can be calculated as follows: (1 -(llt* x 1.5) / (2,094,000 - Tt)) x ARPAt_1 = RPAt Where: • llt * is the expected number of dry tons of tailings to be deposited into Cell 4 B for the ensuing year (period t), based on production estimates for the year (as can be seen from the foregoing formula, this expected number is grossed up by a safety factor of 1.5); • Tt is the actual number of dry tons of tailings solids historically deposited in Cell4B prior to the beginning of period t; and N:\Ce1l4BlJanuary 2011 Submittals and Revisions for CeU4B\DMT Plan 01.10.1I\Tailings Mgnt System and DMT Man Plan Nov 2010 Rv 11.1 - clean. doc White Mesa Mill-Standard Operating Procedures Book 11: Environmental Protection Manual, Section 3.1 01111 Revision: Denisonll.l Page 20 of49 • ARP At-l is the Adjusted Reduced Pool Area for period t-l, which is the pool surface area for the previous period (period t-l) that should have applied during that period, had modeled tonnages (i.e., expected tonnages grossed up by the 150% safety factor) equaled actual tonnages for the period; iii) The required freeboard for period t can be calculated in feet to be the wave run up factor for Cell4B of 0.77 feet plus the quotient of197.5 acre feet divided by the RPAt• The freeboard limit for Cell4A for period t would then be the elevation ofthe FML for Cell 4B of 5594.0 FMSL less this required freeboard amount, rounded to the nearest one-tenth of a foot; and iv) The foregoing calculations will be performed at the Annual Calculation Date for period t and the resulting freeboard limit will persist until the next Annual Calculation Date for period t+ 1. An example of this calculation is set out in Appendix F. (e) When a Spillway is Added to Cell 4B that Allows Overflow Into a New Tailings Cell When a spillway is added between Cell 4B and a new tailings cell then, if an approved freeboard limit calculation method for the new cell is set to cover the entire PMP event for Cells 2,3, 4A, 4B and the new tailings cell, the freeboard limit for Ce1l4B will be inapplicable, except for approved provisions to prevent storm water runoff from overtopping dikes. 6.3.6. Roberts Pond The freeboard limit for Roberts Pond is a liquid maximum elevation of 5 ,624.0 feet above mean sea level, as specified in the GWDP. 6.4. Annual Leak Detection Fluid Samples In the event solution has been detected in a leak detection system, a sample will be collected on an annual basis. This sample will be analyzed according to the conditions set forth in License Condition 11.3. C. The results of the analysis will be reviewed to determine the origin of the solution. 6.5. Annual Inspection of the Decontamination Pads a) New Decontamination Pad During the second quarter of each year, the New Decontamination Pad will be taken out of service and inspected to ensure the integrity of the wash pad's exposed concrete surface. If any abnormalities are identified, i.e. cracks in the concrete with greater than 1/8 inch separation (width) or any significant deterioration or damage of the pad surface, repairs will be made prior to resuming N:\Ce1l4BVanuary 2011 Submittals and Revisions for Ce1l4B\DMT Plan 01.10.IIITailings Mgnt System and DMT Mon Plan Nov 2010 Rv 11.1- c1ean.doc White Mesa Mill -Standard Operating Procedures Book 11: Environmental Protection Manual, Section 3.1 01111 Revision: Denison 11.1 Page 21 of49 the use of the facility. All inspection findings and any repairs required shall be documented on the Annual Decontamination Pad Inspection form. The inspection findings, any repairs required and repairs completed shall be summarized in the 2nd Quarter DMT Monitoring Report due September 1 of each calendar year. b) Existing Decontamination Pad During the second quarter of each year, the Existing Decontamination Pad will be taken out of service and inspected to ensure the integrity of the steel tank. Once the water and any sediment present is removed from the steel tank containment, the walls and bottom of the tank will be visually inspected for any areas of damage, cracks, or bubbling indicating corrosion that may have occurred since the last inspection. If any abnormalities are identified, defects or damage will be reported to Mill management and repairs will be made prior to resuming the use of the facility. All inspection findings and any repairs required shall be documented on the Annual Decontamination Pad Inspection form. A record of the repairs will be maintained as a part of the Annual Inspection records at the Mill site. The inspection findings, any repairs required and repairs completed shall be summarized in the 2nd Quarter DMT Monitoring Report due September 1 of each calendar year. 7. OTHER INSPECTIONS All daily, weekly, monthly, quarterly and annual inspections and evaluations should be performed as specified in Sections 2,3,4,5 and 6 above. However, additional inspections should be conducted after any significant storm or significant natural or man-made event occurs. 8. REPORTING REQUIREMENTS In addition to the Daily Inspection Data, Weekly Tailings Inspection, Monthly Inspection Data and Quarterly Inspection Data forms included as Appendix A and described in Sections 2, 3, 4 and 5 respectively, and the Operating Foreman's Daily Inspection and Weekly Mill Inspection forms described in Sections 2 and 3, respectively, the following additional reports shall also be prepared: 8.1. Monthly Tailings Reports Monthly tailings reports are prepared every month and summarize the previous month's activities around the tailings area. If not prepared by the Radiation Safety Officer, the report shall be submitted to the Radiation Safety Officer for review. The Mill Manager will review the report as well before the report is filed in the Mill Central File. The report will contain a summary of observations of concern noted on the daily and weekly tailings inspections. Corrective measures taken during the month will be documented along with the observations where appropriate. All daily and weekly tailings inspection forms will be attached to the report. A monthly inspection form will also be attached. Quarterly inspection forms will accompany the report when applicable. The report will be signed and dated by the preparer in addition to the Radiation Safety Officer and the Mill N:\CelJ 4BVanuary 2011 Submittals and Revisions for Ce1l4B\DMT Plan 0I.10.1I\Tailings Mgnt System and DMT Mon Plan Nov 2010 Rv 11.1 - clean.doc White Mesa Mill -Standard Operating Procedures Book 11: Environmental Protection Manual, Section 3.1 Manager. 8.2. DMT Reports 01111 Revision: Denisonll.1 Page 22 of49 Quarterly reports ofDMT monitoring activities, which will include the following information, will be provided to the Executive Secretary on the schedule provided in Table 5 of the GWDP: a) On a quarterly basis, all required information required by Part I.F.2 ofthe GWDP relating to the inspections described in Section 3.1 (b) (Slimes Drain Water Level Monitoring), 3.1(d) (Tailings Wastewater Pool and Beach Area Elevation Monitoring), 3.2 (Weekly Inspection of Solution Levels in Roberts Pond) and 3.3 (Weekly Feedstock Storage Area Inspections); b) On a quarterly basis, a summary of the weekly water level (depth) inspections for the quarter for the presence of fluid in all three vertical inspection portals for each of the three chambers in the concrete settling tank system for the New Decontamination Pad, which will include a table indicating the water level measurements in each portal during the quarter; c) With respect to the annual inspection of the New Decontamination Pad described in Section 6.5(a), the inspection findings, any repairs required, and repairs completed shall be summarized in the 2nd Quarter report, due September 1 of each calendar year; d) With respect to the annual inspection of the Existing Decontamination Pad described in Section 6.5(b), the inspection [mdings, any repairs required, and repairs completed shall be summarized in the 2nd Quarter report, due September 1 of each calendar year; and e) An annual summary and graph for each calendar year of the depth to wastewater in the Cell 2 slimes drain must be included in the fourth quarter report. After the first year, and beginning in 2008, quarterly reports shall include both the current year monthly values and a graphic comparison to the previous year. N:\Ce1l4BVanuary 2011 Submittals and Revisions for CeIl4B\DMT Plan OI.lO.ll\Tailings Mgnt System and DMT Mon Plan Nov 2010 Rv 11.1 - clean.doc While Mesa Mill -Standard Opcrating Procedures Book II: Environmental Protection Manu al, Section 3.1 APPENDIX A FORMS 01 /11 Revision: Denison I 1.1 Page 23 of49 N:\CeIl41J\J anuary 201 1 Submil10ls an d Revisions forCeIl4B\J)MT 1'1110 OI.IO.I I\Tailiogs Mgol Sysltm 80d DMT Moo I'lan Nov 2010 Rv 11 .1 • clean.doc White Mesa Mill-Standard Operating Procedures Book 11: Environmental Protection Manual, Section 3.1 01111 Revision: Denisonl1.1 Page 24 of49 APPENDIX A (CONT.) DAILY INSPECTION DATA Any Item not "OK" must be documented. A check mark = OK, X = Action Required I. TAILINGS SLURRY TRANSPORT SYSTEM I Insoection Items Conditions of Potential Concern CellI Slurry Pipeline Leaks, Damage, Blockage, Sharp Bends Pipeline Joints Leaks, Loose Connections Pipeline Supports Damage, Loss of Support Valves Leaks, Blocked, Closed Point(s) of Discharge Improper Location or Orientation II. OPERATIONAL SYSTEMS I Inspection Items Conditions of Potential Concern CellI Water Level Greater Than Operating Level, Large Change Since Previous Inspection Beach Cracks, Severe Erosion, Subsidence Liner and Cover Erosion of cover, Exposure of Liner Liner Observable Liner Damage Cell 2 Cell 2 Inspector: ______ _ Date; ----------Accompanied by: ___ _ Time: --------- Cell 3 Cell4A Cell4B Cell 3 Cell4A Cell4B N:\CeIl4B\January 2011 Submittals and Revisions for CeIl4B\DMT Plan 01.10.11\Tailings Mgnt System and DMT Mon Plan Nov 2010 Rv 11.1 -clean.doc White Mesa Mill-Standard Operating Procedures Book 11: Environmental Protection Manual, Section 3.1 III. DIKES AND EMBANKMENTS Insl2ection Items Conditions of Potential Concern Slopes Sloughs or Sliding Cracks, Bulges, Subsidence, Severe Erosion, Moist Areas, Areas of Seepage Outbreak Crest Cracks, Subsidence, Severe Erosion IV. FLOWRATES SluITV Line(s) GPM Dike I-I I 01111 Revision: Denisonl1.l Page 25 of49 Dike 1-Dike 2 Dike 3 lA Dike 4A-S Pond Return S-X Tails V. PHYSICAL INSPECTION OF SLURRY LINES(S) Walked to Discharge Point Observed Entire Discharge Line VI. DUST CONTROL Dusting Wind Movement of Tailings Precipitation: inches liquid General Meteorological conditions: Cell 2 ______ yes Yes ------ Cell 3 N:\Ce1l4BlJanuary 2011 Submittals and Revisions for Ce1l4B\DMT Plan o 1.10. l1\Tailings Mgnt System and DMT Mon Plan Nov 2010 Rv 11.1 -clean.doc Dike Dike Dike 4A-W 4B-S 4B-W Spray System ______ No No -------' Cell4A Cell4B I White Mesa Mill -Standard Operating Procedures Book 11: Environmental Protection Manual, Section 3.1 VII. DAILY LEAK DETECTION CHECK CellI J l Ce112 Leak Checked Checked Detection System Wet Dry Wet Dry Checked Initial level Initial level Final Final level level Gal. pumped Gal. pumped 01/11 Revision: Denisonll.l Page 26 of49 Cell 3 Ce114A Checked Checked Wet Dry Wet Dry Initial level Initial level Final Final level level Gal. pumped Gal. pumped Cell4B Checked Wet Dry Initial level Final level Gal. pumped VIII OBSERVATIONS OF POTENTIAL CONCERN Action Required N:\Ce1l4B\January 2011 Submittals and Revisions for Ce1l4B\DMT Plan Ol.lO.ll\Tailings Mgnt System and DMT Mon Plan Nov 2010 Rv IU-clean.doc White Mesa Mill -Standard Operating Procedures Book 11: Environmental Protection Manual, Section 3.1 [MAP OF TAILINGS AREA] 01111 Revision: Denisonll.l Page 27 of49 N:\Ce1l4BlJanuary 2011 Submittals and Revisions for Ce1l4B\DMT Plan 01.10.ll\Tailings Mgnt System and DMT Mon Plan Nov 2010 Rv 11.1 -clean. doc White Mesa Mill -Standard Operating Procedures Book 11: Environmental Protection Manual, Section 3.1 01111 Revision: Denison 11.1 Page 28 of49 Date: '-------- 1. Pond and Beach elevations (msl, ft) APPENDIX A (CONT) DENISON MINES (USA) CORP. WEEKLY TAILINGS INSPECTION Inspectors: ____________ _ CellI: (a) Pond Solution Elevation (b) FML Bottom Elevation 5597 __ _ (c) Depth of Water above FML «a)-(b» _____ _ Ce1l4A: (a)Pond Solution Elevation (b)FML Bottom Elevation 5555.14 (c)Depth of Water above FML «a)-(b» _____ _ Ce1l4B: (a)Pond Solution Elevation Roberts (b)FML Bottom Elevation 5557.50 (c)Depth of Water above FML «a)-(b» ____ _ (d)Elevation of Beach Area with Highest Elevation (monthly) Pond: (a)Pond Solution Elevation (b)FML Bottom Elevation ___ 5612.3_ (c)Depth of Water above FML «a)-(b» _____ _ 2. Slimes Drain Liquid Levels Cell 2 Pump functioning properly ___ _ _______ Depth to Liquid pre-pump _______ Depth to Liquid Post-pump (all measurements are depth-in-pipe) Pre-pump head is 38 '-Depth to Liquid Pre-pump = Post-pump head is 38' -Depth to Liquid Post- pump= __ _ N:\CeIl4B\January 2011 Submittals and Revisions for CeIl4B\DMT Plan 01.10.II\Tailings Mgnt System and DMT Mon Plan Nov 2010 Rv 1l.1 - clean. doc White Mesa Mill -Standard Operating Procedures Book 11: Environmental Protection Manual, Section 3.1 3. Leak Detection Systems Observation: CellI Cell 2 Cell 3 01111 Revision: Denisonll.l Page 29 of49 Ce1l4A Cell4B Is LDS wet or wet wet wet wet wet dry? dry dry dry dry dry If wet, Record Ftto Ft to Ftto Ftto Ftto liquid level: Liquid Liquid Liquid Liquid * Liquid * If sufficient Volume Volume Volume Volume Volume fluid is present, record Flow Flow Flow Flow Flow volume of Rate Rate Rate Rate Rate fluid pumped and flow rate: Was fluid --yes __ no --yes __ no --yes __ no --yes __ no --yes __ no sample collected? Observation: New Decon Pad, New Decon Pad, New Decon Pad Portal I Portal 2 Portal 3 Is LDS (Portal) __ wet __ dry __ wet __ dry __ wet __ dry wet or dry? If wet, Record Ftto Ftto Ftto liquid level: Liquid Liquid Liquid If wet, Report to RSO 4. Tailings Area Inspection (Note dispersal of blowing tailings): 5. Control Methods Implemented: _____________________ _ 6. Remarks: ------------------------------------------------------------- N:\Ce1l4B\January 2011 Submittals and Revisions for Ce1l4B\DMT Plan 01.l0.ll\Tailings Mgnt System and DMT Mon Plan Nov 2010 Rv 11.1 - clean.doc White Mesa Mill-Standard Operating Procedures Book 11: Environmental Protection Manual, SectiQn 3. 1 01111 Revision: Denisonll.1 Pagf) 30 of49 7. Contaminated Waste Dump: ______________________ _ * Does Level exceed 12 inches above the lowest point on the bottom flexible membrane liner (solution elevation of 5556.14 amsl for Ce1l4A and 5558.50 for Cell 4B)? no __ yes If Ce1l4A leak detection system level exceeds 12 inches above the lowest point on the bottom flexible membrane liner (elevation 5556.14 amsl), notify supervisor or Mill manager immediately. N:\CcIl 413\Jalluary 2011 Subminals and Revisions for CcIl4 B\OMT Plan OI.IO.II\Tailing' MgOl System and OMT Mon Plan Nov 2010 Rv 11.1 • c1ean.doc White Mesa Mill -Standard Operating Procedures Book 11: Environmental Protection Manual, Section 3.1 APPENDIX A (CONT.) 01111 Revision: Denisonll.1 Page 31 of49 MONTHLY INSPECTION DATA Inspector: __________________________ _ Date: ____________________________ __ 1. Slurry Pipeline: Pipe Thickness: _____ CTo be measured only during periods when the Mill is operating) 2. Diversion Ditches and Diversion Berm: Observation: Diversion Ditches: Sloughing Erosion Undesirable Vegetation Obstruction of Flow Diversion Berm: Stability Issues Signs of Distress Diversion Ditch 1 Diversion Ditch 2 -------.Yes __ no -------.Yes __ no -------.Yes __ no -------.Yes __ no -------.Yes __ no -------.Yes __ no -------.Yes __ no -------.Yes __ no Diversion Ditch 3 Diversion Berm 2 -------.Yes __ no -------.Yes __ no -------.Yes __ no -------.Yes __ no -------.Yes __ no -------.Yes __ no Comments: ______________________________________________________________________ _ 3. Summary of Activities Around Sedimentation Pond: ________________________________ _ N:\Ce1l4BVanuary 2011 Submittals and Revisions for CeU4B\DMT Plan OI.IO.II\Tailings Mgnt System and DMT Mon Plan Nov 2010 Rv 11.1 - clean.doc White Mesa Mill-Standard Operating Procedures Book I I: Environmental Protection Manual, Section 3. I 4. Overspray Dust Minimization: Overspray system functioning properly: __ ~yes ___ no o I III Revision: Denison I 1.I Page 32 of49 Overspray carried more than 50 feet from the cell: ~es no If"yes", was system immediately shut off? ~es __ no Comments: ________________________________ _ 5. Remarks: _______________________________ _ 6. Settlement Monitors Cell 2 WI: Cell 2W3-S: ____ _ Cell 3-1N: ____ _ Cell 2 W2: CeIl2EI-N: ____ _ CeI13-1C: ------Cell 2 W3: Cell 2E1-1S: ____ _ CeIl3-1S: ____ _ Cell 2 W4: Cell 2EI-2S: ____ _ Cell 3-2N: ____ _ Cell 2W7-C: -----Cell 2 East: Cell 2W5-N: ___ _ Cell 2 W7N: ____ _ Cell 2 W7S: ____ _ CeIl 2 W6N: Cell 2 W6C: ____ _ Cell 2 W6S: ____ _ Cell 2 W4N: ___ _ Cell 4A-Toe: -----Cell 2 W4S: ____ _ CeIl 2 W5C: ___ _ Cell 3-2C: ____ _ Cell 3-2S: ____ _ CeIl 2 W5S: ____ _ 7. Summary of Daily, Weekly and Quarterly Inspections: ______________ _ 8. Monthly Slimes Drain Static Head Measurement for Cell 2 (Depth-in-Pipe Water Level Reading): 9. Monthly Slimes Drain Static Head Measurement for Cell 3 (Depth-in-Pipe Water level) (after Cell 3 is closed): N:\CeIl4BVanuary 2011 Submittals and Revisions for CeIl4B\DMT Plan 01.10.II\Tailings Mgnt System and DMT Mon Plan Nov 2010 Rv 11.1 - clean.doc White Mesa MilJ -Standard Operating Procedures Book 11: Environmental Protection Manual, Section 3. I APPENDIX A (CONT.) 0111 1 Revision: Denisonll.l Page 33 of49 WHITE MESA MILL TAILINGS MANAGEMENT SYSTEM QUARTERLY INSPECTION DATA Inspector: __________________________ _ Date: -------------------------------- 1. Embankment Inspection: 2. Operations/Maintenance Review: 3. Construction Activities: -------------------------------------------- 4. Summary: ____________________________________________________ ___ N:\CeIl4B\January 2011 Submittals and Revisions for CeIl4B\DMT Plan 01.10.ll\Tailings Mgnt System and DMT Mon Plan Nov 2010 Rv 11.1 - clean.doc White Mesa Mill-Standard Operating Procedures Book 11: Environmental Protection Manual, Section 3.1 APPENDIX A (CONT.) 01111 Revision: Denisonl1.1 Page 34 of49 ORE STORAGE/SAMPLE PLANT WEEKLY INSPECTION REPORT Week of ____ through ____ Date of lnspection :, _______ _ Inspector: ___________ _ Weather conditions for the week: Blowing dust conditions for the week: Corrective actions needed or taken for the week: Are all bulk feedstock materials stored in the area indicated on the attached diagram: yes: no: ___ _ comments: ------------------------------------- Are all alternate feedstock materials located outside the area indicated on the attached diagram maintained within water-tight containers: yes: no: __ _ comments (e.g., conditions of containers): _________________ _ Are all sumps and low lying areas free of standing solutions? Yes: No: ----If"No", how was the situation corrected, supervisor contacted and correction date? Is there free standing water or water running off of the feedstock stockpiles? Yes: No: ---Comments: ------------------------------------ N:\Ce1l4B\.January 2011 Submittals and Revisions for Ce1l4B\DMT Plan 01.10.ll\Tailings Mgnt System and DMT Mon Plan Nov 2010 Rv 11.1 - clean,doc While Mesa MiII -Standard Operating Procedures l300k I I: Environmental Protection Manual, Section 3. I Other comments: o til I Revision: Denison ILl Page 35 or 49 N:\CcIl4IJ\J8nuary201 I Submil1als Dnd Rl;vislons for Cell 4mDM'!' l'lnn OI.IO.IJ\"allings Mgnt System and I)M'l' Mon I'IHn Nov 2010 Rv 11.1 • clean.doc White Mesa Mill -Standard Operating Procedures Book 11: Environmental Protection Manual, Section 3.1 APPENDIX A (CONT.) 01111 Revision: Denison 1 1.1 Page 36 of49 ANNUAL DECONTAMINATION PAD INSPECTION Date of Inspection: _______ _ Inspector: ___________ _ New Decontamination Pad: Are there any cracks on the wash pad surface greater than 1/8 inch of separation? _Yes _No Is there any significant deterioration or damage of the pad surface? __ Yes __ No Findings: Repair Work Required: Existing Decontamination Pad: Were there any observed problems with the steel tank? __ Yes __ No Findings: Repair Work Required: Note For the annual inspection ofthe both the Existing and New Decontamination Pads, the annual inspection findings, any repairs required, and repairs completed, along with a summary of the weekly inspections, shall be discussed in the 2nd Quarter report, due September 1 of each calendar year N:\CeIl4B\January 2011 Submittals and Revisions for CeIl4B\DMT Plan Ol.lO.II\Tailings Mgnt System and DMT Mon Plan Nov 2010 Rv 11.1 - clean. doc White Mesa Mill -Standard Operating Procedures Book 11: Environmental Protection Manual, Section 3.1 APPENDIXB 01111 Revision: DenisonIl.l Page 37 of49 TAILINGS INSPECTOR TRAINING This document provides the training necessary for qualifying management-designated individuals for conducting daily tailings inspections. Training information is presented by the Radiation Safety Officer or designee from the Environmental Department. Daily tailings inspections are conducted in accordance with the White Mesa Mill Tailings Management System and Discharge Minimization Technology (DMT) Monitoring Plan. The Radiation Safety Officer or designee from the Radiation Safety Department is responsible for performing monthly and quarterly tailings inspections. Tailings inspection forms will be included in the monthly tailings inspection reports, which summarize the conditions, activities, and areas of concern regarding the tailings areas. Notifications: The inspector is required to record whether all inspection items are normal (satisfactory, requiring no action) or that conditions of potential concern exist (requiring action). A "check" mark indicates no action required. If conditions of potential concern exist the inspector should mark an "X" in the area the condition pertains to, note the condition, and specify the corrective action to be taken. If an observable concern is made, it should be noted on the tailings report until the corrective action is taken and the concern is remedied. The dates of all corrective actions should be noted on the reports as well. Any major catastrophic events or conditions pertaining to the tailings area should be reported immediately to the Mill Manager or the Radiation Safety Officer, one of whom will notify Corporate Management. If dam failure occurs, notify your supervisor and the Mill Manager immediately. The Mill Manager will then notify Corporate Management, MSHA (303-231-5465), and the State of Utah, Division of Dam Safety (801-538-7200). Inspections: All areas of the tailings disposal system are routinely patrolled and visible observations are to be noted on a daily tailings inspection form. Refer to Appendix A for an example of the daily tailings inspection form. The inspection form consists of three pages and is summarized as follows: 1. Tailings Slurry Transport System: The slurry pipeline is to be inspected for leaks, damage, and sharp bends. The pipeline joints are to be monitored for leaks, and loose connections. The pipeline supports are to be N:\Ce1l4BVanuary 2011 Submittals and Revisions for Ce1l4B\DMT Plan 01.l0.II\Tailings Mgnt System and DMT Mon Plan Nov 2010 Rv 11.1 - clean.doc White Mesa Mill -Standard Operating Procedures Book II: Environmental Protection Manual, Section 3.1 01111 Revision: Denisonll.l Page 38 of49 inspected for damage and loss of support. Valves are also to be inspected particularly for leaks, blocked valves, and closed valves. Points of discharge need to be inspected for improper location and orientation. 2. Operational Systems: Operating systems including water levels, beach liners, and covered areas are items to be inspected and noted on the daily inspection forms. Sudden changes in water levels previously observed or water levels exceeding the operating level of a pond are potential areas of concern and should be noted. Beach areas that are observed as having cracks, severe erosion or cavities are also items that require investigation and notation on daily forms. Exposed liner or absence of cover from erosion are potential items of concern for ponds and covered areas. These should also be noted on the daily inspection form. Cells 1, 3, 4A and 4B solution levels are to be monitored closely for conditions nearing maximum operating level and for large changes in the water level since the last inspection. All pumping activities affecting the water level will be documented. In Cells 1 and 3, the PVC liner needs to be monitored closely for exposed liner, especially after storm events. It is important to cover exposed liner immediately as exposure to sunlight will cause degradation ofthe PVC liner. Small areas of exposed liner should be covered by hand. Large sections of exposed liner will require the use of heavy equipment These conditions are considered serious and require immediate action. After these conditions have been noted to the Radiation Safety Officer, a work order will be written by the Radiation Safety Officer and turned into the Maintenance Department. All such repairs should be noted in the report and should contain the start and finish date of the repairs. 3. Dikes and Embankments: Inspection items include the slopes and the crests of each dike. For slopes, areas of concern are sloughs or sliding cracks, bulges, subsidence, severe erosion, moist areas, and areas of seepage outbreak. For crests, areas of concern are cracks, subsidence, and severe erosion. When any of these conditions are noted, an "X" mark should be placed in the section marked for that dike. In addition, the dikes, in particular dikes 3, 4A-S, 4A-W, 4B-S, and 4B-W, should be inspected closely for mice holes and more importantly for prairie dog holes, as the prairie dogs are likely to burrow in deep, possibly to the liner. If any of these conditions exist, the inspection report should be marked accordingly. N:\Ce1l4BVanuary 2011 Submittals and Revisions for Ce1l4B\DMT Plan 01.10.ll\Tailings Mgnt System and DMT Mon Plan Nov 2010 Rv 11.1 - clean.doc White Mesa Mill -Standard Operating Procedures Book II: Environmental Protection Manual, Section 3. I 4. Flow Rates: Ol/ll Revision: DenisonIl.1 Page 39 of49 Presence of all flows in and out of the cells should be noted. Flow rates are to be estimated in gallons per minute (GPM). Rates need to be determined for slurry lines, pond return, SX- tails, and the spray system. During non-operational modes, the flow rate column should be marked as "0". The same holds true when the spray system is not utilized. 5. Physical Inspection of Slurry Line(s): A physical inspection of all slurry lines has to be made every 4 hours during operation of the mill. Ifpossible, the inspection should include observation of the entire discharge line and discharge spill point into the cell. If "fill to elevation" flags are in place, the tailings and build-up is to be monitored and controlled so as to not cover the flags. 6. Dust Control: Dusting and wind movement of tailings should be noted for Cells 2,3, 4A, and 4B. Other observations to be noted include a brief description of present weather conditions, and a record of any precipitation received. Any dusting or wind movement of tailings should be documented. In addition, an estimate should be made for wind speed at the time of the observed dusting or wind movement oftailings. The Radiation Safety Department measures precipitation on a daily basis. Daily measurements should be made as near to 8:00 a.m. as possible every day. Weekend measurements will be taken by the Shifter as close to 8:00 a.m. as possible. All snow or ice should be melted before a reading is taken. 7. Observations of Potential Concern: All observations of concern during the inspection should be noted in this section. Corrective action should follow each area of concern noted. All work orders issued, contacts, or notifications made should be noted in this section as well. It is important to document all these items in order to assure that the tailings management system records are complete and accurate. 8. Map of Tailings Cells: The last section of the inspection involves drawing, as accurately as possible, the following items where applicable. N:\Ce1l4BVanuary 2011 Submittals and Revisions for Ce1l4B\DMT Plan 0I.10.11\Tailings Mgnt System and DMT Mon Plan Nov 2010 Rv 11.1 - clean.doc White Mesa Mill -Standard Operating Procedures Book 11: Environmental Protection Manual, Section 3.1 1. Cover area 2. Beach/tailing sands area 3. Solution as it exists 4. Pump lines 01 /11 Revision: Denisonl1.1 Page 40 of49 5. Activities around tailings cell (i.e. hauling trash to the dump, liner repairs, etc.) 6. Slurry discharge when operating 7. Over spray system when operating 9. Safety Rules: All safety rules applicable to the mill are applicable when in the tailings area. These rules meet the required MSHA regulations for the tailings area. Please pay particular notice to the following rules: 1. The posted speed limit for the tailings area is 15 mph and should not be exceeded. 2. No food or drink is permitted in the area. 3. All personnel entering the tailings area must have access to a two-way radio. 4. Horseplay is not permitted at any time. 5. Only those specifically authorized may operate motor vehicles in the restricted area. 6. When road conditions are muddy or slick, a four-wheel drive vehicle is required in the area. 7. Any work performed in which there is a danger of falling or slipping in the cell will require the use of a safety belt or harness with attended life line and an approved life jacket. A portable eyewash must be present on site as well. 8. Anytime the boat is used to perform any work; an approved life jacket and goggles must be worn at all times. There must also be an approved safety watch with a two-way hand- held radio on shore. A portable eyewash must be present on site as well. 10. Preservation of Wildlife: Every effort should be made to prevent wildlife and domesticated animals from entering the tailings area. All wildlife observed should be reported on the Wildlife Report Worksheet during each shift. Waterfowl seen near the tailings cells should be discouraged from landing by the use of noisemakers. 11. Certification: Following the review of this document and on-site instruction on the tailings system inspection program, designated individuals will be certified to perform daily tailings inspections. The Radiation Safety Officer authorizes certification. Refer to the Certification Form, Appendix C. This form should be signed and dated only after a thorough review of the tailings information previously presented. The form will then be signed by the Radiation N:\CeI14B\January 2011 Submittals and Revisions for CeIJ 4B\DMT Plan 01.10.II\Tailings Mgnt System and DMT Mon Plan Nov 2010 Rv 11.1 - clean.doc White Mesa Mill -Standard Operating Procedures Book 11: Environmental Protection Manual, Section 3.1 Safety Officer and filed. 011ll Revision: Denisonl1.1 Page 41 of49 N:\CeIl4BVanuary 2011 Submittals and Revisions for CeIl4B\DMT Plan Ol.lO.II\Tailings Mgnt System and DMT Man Plan Nov 2010 Rv 11.1 - clean.doc White Mesa Mill -Standard Operating Procedures Book II : Environmental Protection Manual, Section 3.1 Al'PENDlXC CERTIFICATION FORM Date: ~~~~~~~~~_ Name: _~~~~~~~~~~ 01/11 Revision: Denison 11 .1 Page 42 of49 I have read the document titled "Tailings Management System, White Mesa Mill Tai lings Inspector Training" and have received on-site instruction at the tailings system. This instruction included documentation of dai ly tai lings inspections, analysis of potential problems (dike failures, unusual flows), notification procedures and safety. Signature I certify that the above-named person is qualified to perform the dai ly inspection of the tail.ings system at the Whi te Mesa Mill. Radiation Safety Personnel! Tailings System Supervi sor N:\CeI14B\lanuary 2011 Sublllinals and Kcvisions lor CcI14u\DMT Ptan OI.IO.II\Tllilings Mgnl SYSlem and DMT Mon I'lan Nov 2010 Rv 11 .1 • clean.doc White Mesa Mill -tandard Operating Procedures Book II: Environmental Protection Manual, Section 3.1 01111 Revision: Denison ILl Page 43 of49 APPENDIXD FEEDSTOCK STORAGE AREA N:\Celi 4B\Jllnuury 20 II ubmiltnls find Revisions for Cell 4B\DMT Plan 0 1.10.II\Tailings Mglll yslclIl and DMT Mon Plan Nov 20 10 Rv ILl - clean.doc White Mesa Mill -Siandard Operating Procedures Ilook I I: Environmental Prolcclion Manual, Section 3.1 APP EN DIX E TABLES 01 /11 Revision: Dcnison l l.l Page 44 of49 N:\CcIl411\January 2011 Subul inal s /lnd Revisions for CcIl4B1DMT Plan 01.10. I I\Tailings Mgnl Syslcm and DMT Mon I'lan Nov 2010 ltv J 1.1 - clean.doc White Mesa Mill-Standard Operating Procedures Book 11: Environmental Protection Manual, Section 3.1 Table lA Calculated Action leakage Rates for Various head Conditions Cell 4A White mesa Mill Blanding, Utah 01111 Revision: Denison 11.1 Page 45 of49 Head above Liner System (feet) Calculated Action leakage Rate 5 10 15 20 25 30 35 37 ( gallons / acre / day) Table IB Calculated Action leakage Rates for Various head Conditions Cell 4 B White mesa Mill Blanding, Utah 222.04 314.01 384.58 444.08 496.50 543.88 587.46 604.01 Head above Liner System (feet) Calculated Action leakage Rate ( gallons / acre / day) 5 211.40 10 317.00 15 369.90 20 422.70 25 475.60 30 528.40 35 570.00 37 581.20 N:\Ce1l4BVanuary 2011 Submittals and Revisions for Ce1l4B\DMT Plan Ol.lO.II\Tailings Mgnt System and DMT Mon Plan Nov 2010 Rv 11.1 - clean. doc White Mesa Mill -Standard Operating Procedures Book II: Environmental Protection Manual, Section 3.1 01 III Revision: Denison 11.1 Page 46 of49 N:ICeIl4B\January 2011 Submittals and Revisions for Cell4BIDMT Plan OI .IO.IIITailings Mgnt System and DMT Mon Plan Nov 2010 Rv 11.1 - clean. doc White Mesa Mill -Standard Operating Procedures Book 11: Environmental Protection Manual, Section 3.1 Assumptions and Factors: APPENDIXF Example of Freeboard Calculations For Ce1l4B 01111 Revision: Denisonl1.1 Page 47 of49 o Total PMP volume to be stored in Cell4A -159.4 acre feet o Wave runup factor for Cell4A -0.77 feet o Total capacity of Cell 4B -2,094,000 dry tons o Elevation ofFML ofCell4B -5,600.35 FMSL o Maximum pool surface area of Cell 4A -40 acres o Total tailings solids deposited into Cell 4B at time beach area first exceeds 5,594 FMSL -1,000,000 dry tons* o Date beach area fust exceeds 5,594, FMSL -March 1,2012* o Expected and actual production is as set forth in the following table: Time Period Expected Expected Actual Tailings Tailings Solids Tailings Solids Disposition into Solids Disposition into Cell 4B Disposition Cell 4B Determined at into Cell determined at the beginning of 4B at the end of the the period (dry beginning period (dry tons)* of the tons)* period, multiplied by 150% Safety Factor (dry_tonsl March 1, 2012 150,000 225,000 225,000 to November 1, 2012 November 1, 300,000 450,000 275,000 2012 to November 1, 2013 November 1, 200,000 300,000 250,000 2013 to November 1, 2014 N:\Cell 4BVanuary 2011 Submittals and Revisions for Cell 4B\DMT Plan 0l.1O.11 \Tailings Mgnt System and DMT Mon Plan Nov 2010 Rv 11 .1 - clean. doc White Mesa Mill -Standard Operating Procedures Book 11: Environmental Protection Manual, Section 3.1 01111 Revision: Denisonl1.1 Page 48 of49 *These expected and actual tailings and production numbers and dates are fictional and have been assumed for illustrative purposes only. Based on these assumptions and factors, the freeboard limits for Ce1l4B would be calculated as follows: 1. Prior to March 1, 2012 Prior to March 1,2012, the maximum elevation of the beach area in Ce1l4B is less than or equal to 5,594 FMSL, therefore the freeboard limit is set at 5,594.6 FMSL. 2. March 1, 2012 to November 1, 2012 The pool surface area would be reduced to the following amount (1 -225,000/ (2,094,000 -1,000,000)) x 40 acres = 31. 77 acres Based on this reduced pool area, the amount of freeboard would be 197.5 acre feet divided by 31.77 acres equals 6.22 feet. When the wave run up factor for Ce1l4B of 0.77 feet is added to this, the total freeboard required is 6.99 feet. This means that the freeboard limit for Ce1l4B would be reduced from 5594.6 FMSL to 5592.2 FMSL (5594.6 FMSL minus 6.22 feet, rounded to the nearest one- tenth of a foot). This calculation would be performed at March 1,2012, and this freeboard limit would persist until November 1,2012. 3. November 1, 2012 to November 1, 2013 The pool surface area would be reduced to the following amount: First, recalculate the pool surface area that should have applied during the previous period, had modeled tonnages (i.e., expected tonnages grossed up by the 150% safety factor) equaled actual tonnages for the period. Since the actual tonnage of225,000 dry tons was the same as the modeled tonnage of 225,000 dry tons, the recalculated pool surface area is the same as the modeled pool surface area for the previous period, which is 31.77 acres. Then, calculate the modeled pool surface area to be used for the period: (1-450,000/ (2,094,000 -1,000,000 -225,000)) x 31.77 acres = 15.32 acres Based on this reduced pool area, the amount of freeboard would be 197.5 acre feet divided by 15.32 acres equals 12.89 feet. When the wave run up factor for Ce1l4B of 0.77 feet is added to this, the total freeboard required is 13.66 feet. This means that the freeboard limit for Cell 4B would be reduced from 5592.2 FMSL to 5586.7 FMSL (5600.35 FMSL minus 13.66 feet, rounded to the nearest one-tenth of a foot). This calculation would be performed at November 1, 2012, and this freeboard limit would persist until November 1,2013. N:\CeIl4BVanuary 201 I Submittals and Revisions for CeIl4B\DMT Plan 0l.I0. I I\Tailings Mgnt System and DMT Mon Plan Nov 2010 Rv 1l.I - clean.doc White Mesa Mill -Standard Operating Procedures Book 11: Environmental Protection Manual, Section 3.1 4. November 1, 2013 to November 1, 2014 The pool surface area would be reduced to the following amount: 01111 Revision: Denisonl1.1 Page 49 of49 First, recalculate the pool surface area that should have applied during the previous period, had modeled tonnages (i.e., expected tonnages grossed up by the 150% safety factor) equaled actual tonnages for the period. Since modeled tonnages exceeded actual tonnages, the pool area was reduced too much during the previous period, and must be adjusted. The recalculated pool area for the previous period is: (1 -275,0001 (2,094,000 -1,000,000 -225,000) x 31.77 acres = 21.72 acres. This recalculated pool surface area will be used as the starting point for the freeboard calculation to be performed at November 1,2013. Then, calculate the modeled pool surface area to be used for the period: (1-300,0001 (2,094,000 -1,000,000 -225,000 -275,000)) x 21.72 acres = 10.75 acres Based on this reduced pool area, the amount of freeboard would be 197.5 acre feet divided by 10.75 acres equals 18.37 feet. When the wave run up factor for Ce1l4B of 0.77 feet is added to this, the total freeboard required is 19.14 feet. This means that the freeboard limit for Cell 4B would be reduced from 5586.7 FMSL to 5581.2 FMSL (5600.4 FMSL minus 18.4 feet, rounded to the nearest one-tenth of a foot). This calculation would be performed at November 1,2013, and this freeboard limit would persist until November 1,2014. N:\CeI14BVanuary 2011 Submittals and Revisions for CeIl4B\DMT Plan 01.10. l1\Tailings Mgnt System and DMT Mon Plan Nov 2010 Rv 11.1 - clean.doc ATTACHMENT 2 PROPOSED REVISON 2.1 TO BAT OPERATIONS AND MANAGEMENT PLAN RED-LINED AND CLEAN VERSIONS ~01/2011 Revision Denison 2.1Q Cell 4A and 4B BAT Monitoring, Operations and Maintenance Plan. Introduction Construction of Cell 4A was authorized by the Utah Department of Environmental Quality, Division of Radiation Control ("DRC) on June 25, 2007. The construction authorization provided that Ce1l4A shall not be in operation until after a BAT Monitoring, Operations and Maintenance Plan is submitted for Executive Secretary review and approval. The Plan shall include requirements in Part LF.3 of the Groundwater Discharge Permit No. UGW370004 ("GWDP") and fulfill the requirements of Parts 1.0.6, 1.E.8, and I.F.9 of the GWDP. Construction ofCell4B was authorized by DRC on June 21, 2010. The construction authorization provided that Cell 4B shall not be in operation until after a BAT Monitoring, Operations and Maintenance Plan is submitted for Executive Secretary review and approval. The Plan shall include requirements in Part I.F.3 of the GWDP and fulfill the requirements of Parts 1.0.12, I.E.12, and I.F.9 ofthe GWDP Cell Design Tailings Ce1l4A consists of the following major elements: a) Dikes -consisting of earthen embankments of compacted soil, constructed between 1989-1990, and composed of four dikes, each including a IS-foot wide road at the top (minimum). On the north, east, and south margins these dikes have slopes of 3H to 1 V. The west dike has an interior slope of 2H to 1 V. Width of these dikes varies; each has a minimum crest width of at least 15 feet to support an access road. Base width also varies from 89-feet on the east dike (with no exterior embankment), to 21 I-feet at the west dike. b) Foundation -including subgrade soils over bedrock materials. Foundation preparation included excavation and removal of contaminated soils, compaction of imported soils to a maximum dry density of 90%. Floor of Cell 4A has an average slope of 1 % that grades from the northeast to the southwest comers. c) Tailings Capacity -the floor and inside slopes of Cell 4A encompass about 40 acres and have a maximum capacity of about 1.6 million cubic yards of tailings material storage (as measured below the required 3-foot freeboard). d) Liner and Leak Detection Systems -including the following layers, in descending order: 1) Primary Flexible Membrane Liner (FML) -consisting of impermeable 60 N'\Ccl! 4!3\J nuary 2011 Submil!als !lnd Rcvi ions for CcIl4BIQ&M Plnn QI.IO.I1ICcI14A nnd 48 0 M PIAn Rev 2-' -Redline docN!\CeIl4Q\J>Iey~~~1I qQ'.o&!M PIIl~II-4A-mId-4B-G-M PlaA ClelHl 2Q IQ JIQ3 .aee Page I ~ Revision [}cni$Oll 2.19 mil high density polyethylene (HOPE) membrane that extends across both the entire cell floor and the inside side-slopes, and is anchored in a trench atlhe top of the dikes on all four sides. The primary FML will be in direct physical contact with the tailings material over most of the Ce ll4A floor area. In Olher locations, the primary FML will be in conlact with the slimes drain collection system (discussed below). NWcll 4/ru'!!!!I'Y 2011 Submjllllaind ItCYlsjo!!S ror Ccll 1PWM PI. 01 10 11\9;11 410 IOd 111 Q M Ply Sa2 ! • RWhnc.4QUI;'C.1I 4iWole" ... h., ''''''''ilH I1114 lhIYisillM I"« CAli 48\OAM 111_ 1I,II.IIJIC.1I4A .... mO M PluCI_ ~OIOIIOUu Page 2 Ce1l4A BAT Monitoring, Operations and Maintenance Plan 1112010 Revision Denison 2.Gl 2) Leak Detection System -includes a permeable HDPE geonet fabric that extends across the entire area under the primary FML in Cell 4A, and drains to a leak detection sump in the southwest corner. Access to the leak detection sump is via an I8-inch inside diameter (ID) PVC pipe placed down the inside slope, located between the primary and secondary FML liners. At its base this pipe will be surrounded with a gravel filter set in the leak detection sump, having dimensions of 10 feet by 10 feet by 2 feet deep. In turn, the gravel filter layer will be enclosed in an envelope of geotextile fabric. The purpose of both the gravel and geotextile fabric is to serve as a filter. 3) Secondary FML -consisting of an impermeable 60-mil HDPE membrane found immediately below the leak detection geonet. Said FML also extends across the entire Cell 4A floor, up the inside side-slopes and is also anchored in a trench at the top of all four dikes. 4) Geosynthetic Clay Liner -consisting of a manufactured geosynthetic clay liner (GCL) composed of 0.2-inch of low permeability bentonite clay centered and stitched between two layers of geotextile. Prior to disposal of any wastewater in Cell 4A, the Permittee shall demonstrate that the GCL has achieved a moisture content of at least 50% by weight. This item is a revised requirement per DRC letter to DUSA dated September 28,2007 e) Slimes Drain Collection System -including a two-part system of strip drains and perforated collection pipes both installed immediately above the primary FML, as follows: 1) Horizontal Strip Drain System -is installed in a herringbone pattern across the floor of Cell 4A that drain to a "backbone" of perforated collection pipes. These strip drains are made of a prefabricated two-part geo-composite drain material (solid polymer drainage strip) core surrounded by an envelope of non-woven geotextile filter fabric. The strip drains are placed immediately over the primary FML on 50-foot centers, where they conduct fluids downgradient in a southwesterly direction to a physical and hydraulic connection to the perforated slimes drain collection pipe. A series of continuous sand bags, filled with filter sand cover the strip drains. The sand bags are composed of a woven polyester fabric filled with well graded filter sand to protect the drainage system from plugging. 2) Horizontal Slimes Drain Collection Pipe System -includes a "backbone" piping system of 4-inch ill Schedule 40 perforated PVC slimes drain collection (SDC) pipe found at the downgradient end of the strip drain lines. This pipe is in turn overlain by a berm of gravel that runs the entire diagonal length of the cell, surrounded by a geotextile fabric cushion in immediate contact with the primary FML. The non-woven geotextile material is overlain at the surface by a woven geotextile fabric. which is N'\Cell 4BVi!!ll!ll/'Y 2011 SubmjUllls and Revisions (orCeIl 4G\Q&MPlan 01 10.l l1Cc1l4A ond 4B Q M Plan Rey 2,1 -Redline.doc~H>\ibmiIl&lH~ien5-ferGe PieR CleaR 2QHlIIQ].aee Page 3 Cell4A BAT Monitoring, Operations and Maintenance Plan \112010 Revision Denison 2·g1 ballasted laterally bv sandbags Oil each side of the backbone of the benn. In turn, the gravel is overlain by a layer of non-woven geotextile to serve as an additional filter material. This perforated collection pipe serves as the "backbone" to the slimes drain system and runs from the far northeast corner downhill to the far southwest corner of Cell 4A where it joins the slimes drain access pipe. 3) Slimes Drain Access Pipe -consisting of an I8-inch ID Schedule 40 PVC pipe placed down the inside slope of Cell 4A at the southwest corner, above the primary FML. Said pipe then merges with another horizontal pipe of equivalent diameter and material, where it is enveloped by gravel and nonwoven geotextile that serves as a cushion to protect the primary FML. The non-woven geotextile material is overlain at the surface by a woven. geotexti le fabric, wh ich is ballasted by sandbags.A reducer connects the horizontal I8-inch pipe with the 4-inch SDC pipe. At some future time, a pump will be set in this I8-inch pipe and used to remove tailings wastewaters for purposes of de-watering the tailings cell. f) Dike Splash Pads - A minimum of eight (8) 20-foot wide splash pads are installed on the interior dike slopes to protect the primary FML from abrasion and scouring by tailings slurry. These pads consist of an extra layer of 60 mil HDPE membrane that is placed down the inside slope of Cell 4A, from the top of the dike and down the inside slope. The pads extend to a point 5-feet beyond the toe of the slope to protect the liner bottom during initial startup of the Cell. The exact location of the splash pads is detailed on the As-Built Plans and Specifications. g) Rub Protection Sheets -In addition to the splash pads described in f) above, rub sheets are installed beneath all piping entering or exiting Cell 4A that is not located directly on the splash pads. h) Emergency Spillway - a concrete lined spillway constructed near the western corner of the north dike to allow emergency runoff from Cell 3 into Cell 4A. This spillway will be limited to a 6-inch reinforced concrete slab set directly over the primary FML in a 4-foot deep trapezoidal channel. A second spillway has been constructed in the southwest corner of Cell 4A to allow emergency runoff from Cell 4A into Cell 48. All stormwater runoff and tailings wastewaters not retained in Cells 3 and 4A, will be managed and contained in Cell 4B, including the Probable Maximum Precipitation and flood event. Tailings Ce1l4B consists of the following major elements: a) Dike -consisting of a newly-constructed dike on the south side of the cell with a I5-foot wide road at the top (minimum) to support an access road. The grading plan for the Cell 4B excavation includes interior slopes of 2H to 1 V. The exterior slope of the southern dike will have the typical slopes of 3H to 1 V. Limited portions of the Cell 4B interior sideslopes in the northwest corner and southeast corner of the cell (where the slimes drain N'\Cel! 1 BIJgnugry 2011 SubmiUals and Revjsions [<;If Ccll4BIQ&M Pllm 01.10.1 1\0:11 4A lind 4B Q M Plgn RI'V 2.1 -Redline doc~~visien!l-fl!r Ce1l 4B\O&M-PI~ntl-48-Q-M Pillfl Clellfl 2QHlI Hl3.ase Page 4 Ce1l4A BAT Monitoring, Operations and Maintenance Plan 1112010 Revision Denison 2.Gl and leak detection sump will be located) will also have a slope of 3H to 1 V. The base width of the southern dike varies from approximately 100 feet at the western end to approximately 190 feet at the eastern end of the dike, with no exterior embankment present on any other side of the cell. b) Foundation -including subgrade soils over bedrock materials. Foundation preparation included 6-inch over excavation of rock and placement and compaction of imported soils to a maximum dry density of 90% at a moisture content between +3% and -3% of optimum moisture content, as determined by ASTM D-1557. The floor of Cell 4B has an average slope of I % that grades from the northwest corner to the southeast corner. c) Tailings Capacity -the floor and inside slopes of Cell 4B encompass about 45 acres and the cell will have a water surface area of 40 acres and a maximum capacity of about 1.9 million cubic yards of tailings material storage (as measured below the required 3-foot freeboard). d) Liner and Leak Detection Systems -including the following layers, in descending order: 1) Primary Flexible Membrane Liner (FML) -consisting of 60 mil high density polyethylene (HDPE) membrane that extends across both the entire cell floor and the inside side-slopes, and is anchored in a trench at the top of the dikes on all four sides. The primary FML will be in direct physical contact with the tailings material over most of the Cell 4B floor area. In other locations, the primary FML will be in contact with the slimes drain collection system (discussed below). 2) Leak Detection System -includes a permeable HDPE geonet fabric that extends across the entire area under the primary FML in Cell 4B, and drains to a leak detection sump in the southeast corner. Access to the leak detection sump is via aft ~2-foot inside diameter (ID) PVC pipe placed down the inside slope, located between the primary and secondary FML liners. At its base this pipe will be surrounded with a gravel filter set in the leak detection sump, having dimensions of 10 feet by 10 feet by 2 feet deep. In turn, the gravel filter layer will be enclosed in an envelope of geotextile fabric. The purpose of both the gravel and geotextile fabric is to serve as a filter. 3) Secondary FML -consisting of a 60-mil HDPE membrane found immediately below the leak detection geonet. Said FML also extends across the entire Cell 4B floor, up the inside side-slopes and is also anchored in a trench at the top of all four dikes. 4) Geosynthetic Clay Liner -consisting of a manufactured geosynthetic clay liner (GCL) composed of 0.2-inch of low permeability bentonite clay centered and stitched between two layers of geotextile. Prior to disposal of any wastewater in Cell 4B, the Permittee shall demonstrate that the GCL ha_~. achieved a moisture content of at least 50% by weight. N'\Cc]! 40\Jnnunry 201 1 Subminalsand Revisio!!$ for CcIl 4B\Q&M Plnn 91 \0.I 1\C9114A nnd 40 0 M Phm Rev 2.1 - Redline docN:l,(;eIl4Q\,N_bef-SIJbmiual. Blld Re'fisiens fer~n 11.1 \,IQ'£e114i\ &nd4B-G-M PlaR CleaR 2QHJ\ \Q3.!lss Page 5 Cell 4A BAT Monitoring, Operations and Maintenance Plan 1112010 Revision Denison 2.01 e) Slimes Drain Collection System -including a two-part system of strip drains and perforated collection pipes both installed immediately above the primary FML, as follows: 1) Horizontal Strip Drain System -is installed in a herringbone pattern across the floor of Cell 4B that drain to a "backbone" of perforated collection pipes. These strip drains are made of a prefabricated two-part geo-composite drain material (solid polymer drainage strip) core surrounded by an envelope of non-woven geotextile filter fabric. The strip drains are placed immediately over the primary FML on 50-foot centers, where they conduct fluids downgradient in a southeasterly direction to a physical and hydraulic connection to the perforated slimes drain collection pipe. A series of continuous sand bags, filled with filter sand cover the strip drains. The sand bags are composed of a woven polyester fabric filled with well graded filter sand to protect the drainage system from plugging. 2) Horizontal Slimes Drain Collection Pipe System -includes a "backbone" piping system of 4-inch ill Schedule 40 perforated PVC slimes drain collection (SOC) pipe found at the down gradient end of the strip drain lines. This pipe is in tum overlain by a berm of gravel that runs the entire diagonal length of the cell, surrounded by a geotextile fabric cushion in immediate contact with the primary FML. In tum, the gravel is overlain by a layer of non-woven geotextile to serve as an additional filter material. The non-woven geotextile material is overlain at the surface by a woven geotextile fabric. which is ballasted by sandbags. This perforated collection pipe serves as the "backbone" to the slimes drain system and runs from the far northwest corner downhill to the far southeast comer of Cell 4B where it joins the slimes drain access pipe. 3) Slimes Drain Access Pipe -consisting of an IS-inch ID Schedule 40 PVC pipe placed down the inside slope of Cell 4B at the southeast comer, above the primary FML. Said pipe then merges with another horizontal pipe of equivalent diameter and material, where it is enveloped by gravel and non:woven geotextile that serves as a cushion to protect the primary FML. The non-woven geotextile material is overlain at the surface by a woven geotextile fabric, which is ballasted laterally by sandbags on each side of the backbone of the berm. A reducer connects the horizontal IS- inch pipe with the 4-inch SDC pipe. At some future time, a pump will be set in this IS-inch pipe and used to remove tailings wastewaters for purposes of de-watering the tailings cell. f) Cell 48 North and East Dike Splash Pads -Nine 20-foot-wide splash pads will be constructed on the north and east dikes to protect the primary FML from abrasion and scouring by tailings slurry. These pads will consist of an extra layer of textured, 60 mil HDPE membrane that will be installed in the anchor trench and placed down the inside slope of Cell 48, from the top of the dike, under the inlet pipe, and down the inside slope to a point at N:\Gc1l4QUanUllry 2011 Sybmjllplsand Rcyi~ion~ forCeIl4B\Q&M Plan 01 10 !I\c&1I 4A Md 4B 0 M Pion Rev 2 I -Redline.do~)I:\Cell 4B'~low"lbef-SllhmittaJs-&lId Re"isioAS rer Cell 4B\O&M PIIiR 11.11.1~Cell 41. &11 a 49 0 M PlaH CleaH 2(JHlI IIn.ase Page 6 Cell4A BAT Monitoring, Operations and Maintenance Plan 1112010 Revision Denison 2.Gl least 5 feet onto the Cell 4B floor beyond the toe of the slope. g) Rub Protection Sheets -In addition to the splash pads described in f) above, rub sheets are installed beneath all piping entering or exiting Cell 4B that is not located directly on the splash pads. h) Emergency Spillway - a concrete lined spillway constructed near the southern corner of the east dike to allow emergency runoff from Cell 4A into Cell 4B. This spillway will be limited to a 6-inch reinforced concrete slab, with a welded-wire fabric installed within its midsection, set atop a cushion geotextiJe placed directly over the primary FML in a 4-foot deep trapezoidal channel. A 100 foot wide, 60 mil HDPE geomembrane splash pad will be installed beneath the emergency spillway. No other spillway or overflow structure will be constructed at Cell 4B. All storm water runoff and tailings wastewaters not retained in Cells 2, 3 and 4A, will be managed and contained in Cell 4B, including the Probable Maximum Precipitation and flood event. Cell Operation Solution Discharge to Cell 4A Cell 4A will initially be used for storage and evaporation of process solutions from the Mill operations. These process solutions will be from the uranium/vanadium solvent extraction circuit, or transferred from Cell 1 evaporation pond or the free water surface from Cell 3, or transferred from Cell 2 tailings dewatering operations. The solution will be pumped to Cell 4A through 6 inch or 8 inch diameter HDPE pipelines. The initial solution discharge will be in the southwest comer of the Cell. The solution will be discharged in the bottom of the Cell, away from any sand bags or other installation on the top of the FML. Building the solution pool from the low end of the Cell will allow the solution pool to gradually rise around the slimes drain strips, eliminating any damage to the strip drains or the sand bag cover due to solution flowing past the drainage strips. The solution will eventually be discharged along the dike between Cell 3 and CeIl4A, utilizing the Splash Pads described above. The subsequent discharge of process solutions will be near the floor of the pond, through a discharge header designed to discharge through multiple points, thereby reducing the potential to damage the Splash Pads or the Slimes Drain system. At no time, subsequent to initial filling, will the solution be discharged into less than 2 feet of solution. As the cell begins to fill with solution the discharge point will be pulled back up the Splash Pad and allowed to continue discharging at or near the solution level. Solution Discharge to Cell 4B Cell 4B will initially be used for storage and evaporation of process solutions from the Mill operations. These process solutions will be from the uranium/vanadium solvent extraction circuit, or transferred from Cell 1 evaporation pond or the free water surface from Cell 3 or Cell 4A, or transferred N'\CcIl 4B\lanupry 2011 SUbmi!lals and Revisions fQcCeIl 4l3IQ&M plan 01 10 Il\Ce1l 4A and 4B 0 M Plan Rev 2, I -Redline docNi\Ge1l 4BINevemger SIlbmi-ltlH9il~R~&M IIla~\Cel! 4,0. and 4B 0 M ~R CleaR 2GJQJJG3 .eee Page 7 Ce1l4A BAT Monitoring, Operations and Maintenance Plan 1112010 Revision Denison 2.01 from Cell 2 dewatering operations. The solution will be pumped to Cell 4B through 6 inch or 8 inch diameter HDPE pipelines. The initial solution discharge will be in the southeast comer of the Cell. The discharge pipe will be routed down the Splash Pad provided in the southeast comer of the Cell at the spillway to protect the primary FML. The solution will be discharged in the bottom of the Cell, away from any sand bags or other installation on the top of the FML. Building the solution pool from the low end of the Cell will allow the solution pool to gradually rise around the slimes drain strips, eliminating any damage to the strip drains or the sand bag cover due to solution flowing past the drainage strips. The solution will eventually be discharged along the dike between Cell 3 and Cell 4B, utilizing the Splash Pads described above. The subsequent discharge of process solutions will be near the floor of the pond, through a discharge header designed to discharge through multiple points, thereby reducing the potential to damage the Splash Pads or the Slimes Drain system. At no time, subsequent to initial filling, will the solution be discharged into less than 2 feet of solution. As the cell begins to fill with solution the discharge point will be pulled back up the Splash Pad and allowed to continue discharging at or near the solution level. Initial Solids Discharge into Cell 4A Once Cell 4A is needed for storage for tailings solids the slurry discharge from No.8 CCD thickener will be pumped to the cell through 6 inch or 8 inch diameter HDPE pipelines. The pipelines will be routed along the dike between Cell 3 and Cell 4A, with discharge valves and drop pipes extending down the Splash Pads to the solution level. One or all of the discharge points can be used depending on operational considerations. Solids will settle into a cone, or mound, of material under the solution level, with the courser fraction settling out closer to the discharge point. The initial discharge locations are shown on Figure lAo Figure 2A illustrates the general location of the solution and slurry discharge pipelines and control valve locations. The valves are 6" or 8" stainless steel knife-gate valves. The initial discharge of slurry will be at or near the toe of the Cell slope and then gradually moved up the slope, continuing to discharge at or near the water surface. This is illustrated in Section A-A on Figure 2A. Because of the depth of Cell 4A, each of the discharge points will be utilized for an extended period of time before the cone of material is above the maximum level of the solution. The discharge location will then be moved further to the interior of the cell allowing for additional volume of solids to be placed under the solution level. The solution level in the cell will vary depending on the operating schedule of the Mill and the seasonal evaporation rates. The tailings slurry will not be allowed to discharge directly on to the Splash Pads, in order to further protect the FML. The tailings slurry will discharge directly in to the solution contained in the Cell, onto an additional protective sheet, or on to previously deposited tailings sand. Initial Solids Discharge into Cell 4B N'\CcIl 4BlJanuarv 2011 Submj!!lIlsandRevisjons for Cel! 4BIO&M Plan DI.lO l llCel\ 4A and 43 0 M Plnn Rev 2 I -Redline.doci>l!'£eIl 48\N()Yembef.SOOllliltlliHna Re .. isioll5 fur GeIl 4B\.o&~4 Pla~ PlaR CleaR 2QHlI Hl3.dee Page 8 Cell4A BAT Monitoring, Operations and Maintenance Plan 1112010 Revision Denison 2·()1 Once Cell 4B is needed for storage for tailings solids the slurry discharge from No.8 CCO thickener will be pumped to the cell through 6 inch or 8 inch diameter HOPE pipelines. The pipelines will be routed along the dike between Cell 3 and Cell 4B, with discharge valves and drop pipes extending down the Splash Pads to the solution level. One or all of the discharge points can be used depending on operational considerations. Solids will settle into a cone, or mound, of material under the solution level, with the courser fraction settling out closer to the discharge point. The initial discharge locations are shown on Figure 1 B. Figure 2B illustrates the general location of the solution and slurry discharge pipelines and control valve locations. The valves are 6" or 8" stainless steel knife-gate valves. The initial discharge of slurry will be at or near the toe of the Cell slope and then gradually moved up the slope, continuing to discharge at or near the water surface. This is illustrated in Section A-A on Figure 2B. Because of the depth of Cell 4B, each of the discharge points will be utilized for an extended period of time before the cone of material is above the maximum level of the solution. The discharge location will then be moved further to the interior of the cell allowing for additional volume of solids to be placed under the solution level. The solution level in the cell will vary depending on the operating schedule of the Mill and the seasonal evaporation rates. The tailings slurry will not be allowed to discharge directly on to the Splash Pads, in order to further protect the FML. The tailings slurry will discharge directly in to the solution contained in the Cell, onto an additional protective sheet, or on to previously deposited tailings sand. Equipment Access to Cell 4A and Ce1l4B Access will be restricted to the interior portion of the cells due to the potential to damage the flexible membrane liners. Only low pressure rubber tired all terrain vehicles or foot traffic will be allowed on the flexible membrane liners. Personnel are also cautioned on the potential damage to the flexible membrane liners through the use and handling of hand tools and maintenance materials. Reclaim Water System at Cell 4A A pump barge and solution recovery system is operating in the southwest comer of the cell to pump solution from the cell for water balance purposes or for re-use in the Mill process. Figure 3A illustrates the routing of the solution return pipeline and the location of the pump barge. The pump barge will be constructed and maintained to ensure that the flexible membrane liner is not damaged during the initial filling of the cell or subsequent operation and maintenance activities. The condition of the pump barge and access walkway will be noted during the weekly Cell inspections. Reclaim Water System at Cell 4B A pump barge and solution recovery system will be installed in the southeast N;\CeIl 4B\lnnuruy 201 I Submittals And Revisions for Cell 4B\Q&M Plnn 01.10 II\Cell4A and 4B 0 M Plan Rev 2; I -Redline.doc~ll-4ffiNiJYe~~i!;ieA~ fer Cell 4B-\O&M Pin" 1\.11.1 o\C811 V, and 4B-Q-.M PlaA CleaR 2QIQ]IQJ.eae Page 9 Cell4A BAT Monitoring, Operations and Maintenance Plan 1112010 Revision Denison 2.Ql corner of the cell to pump solution from the cell for water balance purposes or for re-use in the Mill process. Figure 3B illustrates the routing of the solution return pipeline and the location of the pump barge. The pump barge will be constructed and maintained to ensure that the flexible membrane liner is not damaged during the initial filling of the cell or subsequent operation and maintenance activities. The condition of the pump barge and access walkway will be noted during the weekly Cell inspections. Interim Solids Discharge to Ce1l4A Figure 4A illustrates the progression of the slurry discharge points around the north and east sides of Cell 4A. Once the tailings solids have been deposited along the north and east sides of the Cell, the discharges points will subsequently be moved to the sand beaches, which will eliminate any potential for damage to the liner system. Interim Solids Discharge to Cell 4B Figure 4B illustrates the progression of the slurry discharge points around the north and east sides of Cell 4B. Once the tailings solids have been deposited along the north and east sides of the Cell, the discharges points will subsequently be moved to the sand beaches, which will eliminate any potential for damage to the liner system. Liner Maintenance and QAlQC for Cell 4A Any construction defects or operational damage discovered during observation of the flexible membrane liner will be repaired, tested and documented according to the procedures detailed in the approved Revised Construction Quality Assurance Plan for the Construction of the Cell 4A Lining System, May 2007, by GeoSyntec Consultants. Liner Maintenance and QA/QC for Cell 4B Any construction defects or operational damage discovered during observation of the flexible membrane liner will be repaired, tested and documented according to the procedures detailed in the approved Construction Quality Assurance Plan for the Construction of the Cell 4B Lining System, October 2009, by Geosyntec Consultants. BAT Performance Standards for Tailings Cell 4A and 4B DUSA will operate and maintain Tailings Cell 4A and 4B so as to prevent release of N;\cc:.!l 4B\Jnnuary2Ql ! SubmiUnlsgnd Revjsions for Ce1l4I3\O&M Plan QUO JJ\Ce1l 4A and 46 Q M rlgn Rqv2, J . RedJine doc~I-4~&Yeftlbllr-SuIImit~1lS-fuf'-Ge1l 4B\O&H Plan 11.1 1.1 QlCllll 4A II!Id 48 Q H PieR CleaR 2!lHlII!l3.dse Page 10 Cell4A BAT Monitoring, Operations and Maintenance Plan 1112010 Revision Denison 2.G! wastewater to groundwater and the environment in accordance with this BAT Monitoring Operations and Maintenance Plan, pursuant to Part I.H.8 of the GWDP. These performance standards shall include: 1) Leak Detection System Pumping and Monitoring Equipment -the leak detection system pumping and monitoring equipment in each cell includes a submersible pump, pump controller, water level indicator (head monitoring), and flow meter with volume totalizer. The pump controller is set to maintain the maximum level in the leak detection system in each cell at no more than 1 foot above the lowest level of the secondary flexible membrane, not including the sump (i.e. lie mele !:haft 3 feet eee,'e ike BOttOfB of the Sl:lfBfJ). A second leak detection pump with pressure transducer, flow meter, and manufacturer recommended spare parts for the pump controller and water level data collector is maintained in the Mill warehouse to ensure that the pump and controller can be replaced and operational within 24 hours of detection of a failure of the pumping system. The root cause of the equipment failure will be documented in a report to Mill management with recommendations for prevention of a re- occurrence. 2) Maximum Allowable Head -the Permittee shall measure the fluid head above the lowest point on the secondary flexible membrane in each cell by the use of procedures and equipment specified in the White Mesa Mill Tailings Management System and Discharge Minimization Technology (DMT) Monitoring Plan, 10/10 Revision: Denison-tO.2, or the currently approved DMT Plan. Under no circumstance shall fluid head in the leak detection system sump exceed a I-foot level above the lowest point in the lower flexible membrane liner, not including the sump (Le. Re lIIore tBlIfI 3 feet aBeo.'e the aoUem efttie Sl:lH'Ip). 3) Maximum Allowable Daily LDS Flow Rates -the Permittee shall measure the volume of all fluids pumped from each LDS on a weekly basis, and use that information to calculate an average volume pumped per day. Under no circumstances shall the daily LDS flow volume exceed 24,160 gallons/day for Cell 4A or 26,145 gallons/day for Cell 4B. The maximum daily LDS flow volume will be compared against the measured cell solution levels detailed on the attached Table lA or IB for Cells 4A or 4B, respectively, to determine the maximum daily allowable LDS flow volume for varying head conditions in the cell. 4) 3-foot Minimum Vertical Freeboard Criteria -the Permittee shall operate and maintain wastewater levels to provide a 3-foot Minimum of vertical freeboard in Tailings Cell 4A and Cell 4B. Said measurements shall be made to the nearest 0.1 foot. 5) Slimes Drain Recovery Head Monitoring -immediately after the N·\(".t1l4B\1anuary 2011 Submjllal. pnd Revisions for Ce1l4B\O&M plan QJ JO I !\Coll4Aand 4S 0 M Plan"Rey 2.1 -Redline docNH.GeU-4W.We~ul!mtI~Rd ReYISi9RHer Cell 4B\o&M PlaR II.ll.lGiCeli 4 ... BAd 'IS 0 .4 PlaR CleaR 2()HlI Hl3.89G Page 11 Cel14A BAT Monitoring, Operations and Maintenance Plan \112010 Revision Denison 2·Ql Permittee initiates pumping conditions in the Tailings Cell 4A or Cell 4B slimes drain system, monthly recovery head tests and fluid level measurements will be made in accordance with a plan approved by the DRC Executive Secretary. The slimes drain system pumping and monitoring equipment, includes a submersible pump, pump controller, water level indicator (head monitoring), and flow meter with volume totalizer. Routine Maintenance and Monitoring Trained personnel inspect the White Mesa tailings system on a once per day basis. Any abnormal occurrences or changes in the system will be immediately reported to Mill management and maintenance personnel. The inspectors are trained to look for events involving the routine placement of tailings material as well as events that could affect the integrity of the tailings cell dikes or lining systems. The daily inspection reports are summarized on a monthly basis and reviewed and signed by the Mill Manager. Solution Elevation Measurements of solution elevation in Cell 4A and Cell 4B are to be taken by survey on a weekly basis, and measurements of the beach area in Cell4A and Cell 4B with the highest elevation are to be taken by survey on a monthly basis, by the use of the procedures and equipment specified in the latest approved edition ofthe DMTPlan. Leak Detection System The Leak Detection System in Cell 4A and Cell 4B is monitored on a continuous basis by use of a pressure transducer that feeds water level information to an electronic data collector. The water levels are measured every hour and the information is stored for later retrieval. The water levels are measured to the nearest 0.10 inch. The data collector is currently programmed to store 7 days of water level information. The number of days of stored data can be increased beyond 7 days if needed. The water level data is downloaded to a laptop computer on a weekly basis and incorporated into the Mill's environmental monitoring data base, and into the files for weekly inspection reports of the tailings cell leak detection systems. Within 24 hours after collection of the weekly water level data, the information will be evaluated to ensure that: 1) the water level in the Cell 4A and Cell 4B leak detection sumps did not exceed the allowable level (5556.14 feet amsl in the Cell 4A LDS sump and 5558.5 feet amsl in the Cell4B sump), and 2) the average daily flow rate from the LDS did not exceed the maximum daily allowable flow rate at any time N; Ce1l 4B\janUArv 2011 Submll1!!ls and Revisinn~ far CcJl1B\O&M plan 01.10, \1\Ceu 16 And 413 0 M Plan Rev 2 I -Redline doc~l:\CeIl1B\l>lovelllb*&Jbllliiltls ellil Re'~siIlRs fer Cell 4B\o&M Plan 'I II Hl\c~I~ PlaR CleaR 2()IQIW3.Elae Page 12 Ce1l4A BAT Monitoring, Operations and Maintenance Plan 1112010 Revision Denison 2.()! during the reporting period. For Cell 4A and Cell 4B, under no circumstance shall fluid head in the leak detection system sump exceed a I-foot level above the lowest point in the lower flexible membrane liner, not including the sump~aa 3 feet above ilie bortoffi ef the SttHtpj. To determine the Maximum Allowable Daily LDS Flow Rates in the Cell 4A and Cell 4B leak detection system, the total volume of all fluids pumped from the LDS of each cell on a weekly basis shall be recovered from the data collector, and that information will be used to calculate an average volume pumped per day for each cell. Under no circumstances shall the daily LDS flow volume exceed 24,160 gallons/day from Cell 4A or 26,145 gallons/day from Cell 4B. The maximum daily LDS flow volume will be compared against the measured cell solution levels detailed on the attached Tables lA and lB, to determine the maximum daily allowable LDS flow volume for varying head conditions in Cell 4A and Cell 4B. Any abnormal or out of compliance water levels must be immediately reported to Mill management. The data collector on each cell is also equipped with an audible alarm that sounds if the water level in the leak detection sump exceeds the allowable level (5556.14 feet amsl in the Cell4A LDS sump and 5558.5 feet amsl in the Cell 4B sump). The current water level is displayed at all times on each data collector and available for recording on the daily inspection form. Each leak detection system is also equipped with a leak detection pump, EPS Model # 25S05- 3 stainless steel, or equal. Each pump is capable of pumping in excess of 25 gallons per minute at a total dynamic head of 50 feet. Each pump has a 1.5 inch diameter discharge, and operates on 460 volt 3 phase power. Each pump is equipped with a pressure sensing transducer to start the pump once the level of solution in the leak detection sump is approximately 2.25 feet (elevation 5555.89 in the Cell 4A LOS sump and 5557.69 feet amsl in the Cell 4B sump) above the lowest level of the leak detection sump (9 inches above the lowest point on the lower flexible membrane liner for Cell 4A and 3 inches for Cell 4B), to ensure the allowable 1.0 foot (5556.14 feet amsl in the Cell 4A LOS sump and 5558.5 feet amsl in the Cell4B sump) above the lowest point on the lower flexible membrane liner is not exceeded). The attached Figures 6A and 6B (Cell 4A and 4B, respectively), Leak Detection Sump Operating Elevations, illustrates the relationship between the sump elevation, the lowest point on the lower flexible membrane liner and the pump-on solution elevation for the leak detection pump. The pump also has manual start and stop controls. The pump will operate until the solution is drawn down to the lowest level possible, expected to be approximately 4 inches above the lowest level of the sump (approximate elevation 5554.0 and 5555.77 ft amsl for Cells 4A and 4B, respectively). The pump discharge is equipped with a 1.5 inch flow meter, EPS Paddle Wheel Flowsensor, or equal, that reads the pump discharge in gallons per minute, and records total gallons pumped. The flow rate and total gallons are recorded by the Inspector on the weekly inspection form. The leak detection pump is N'\CcI! 4B\Januarv 201 I Sybmitl4!s and Revisions [or Cell 4B\Q&M PI n () I 10. I I\CoII 4A ond 4B a M Plan Rev 2. I -RedlinedocJ>l;l.GeU-4i1l.N_~&I5-iI~I~QI~ PIIIR CleaR 2QHlI Hl3.eae Page 13 Cell 4A BAT Monitoring, Operations and Maintenance Plan 1112010 Revision Denison H l installed in the horizontal section of the 18 inch, perforated section of the PVC collection pipe. The distance from the top flange face, at the collection pipe invert, to the centerline of the 22.5 degree elbow is 133.4 feet in Cell 4A and 135.6 feet in Cell 4B, and the vertical height is approximately 45 feet in Cell 4A and approximately 42.5 feet in Cell 4B. The pump is installed at least 2 feet beyond the centerline of the elbow. The bottom of the pump will be installed in the leak detection sump at least 135.4 feet in Cell 4A and l37.6 feet in Cell 4B or more from the top of the flange invert. A pressure transducer installed within the pump continuously measures the solution head and is programmed to start and stop the pump within the ranges specified above. The attached Figure 5, illustrates the general configuration of the pump installation. A spare leak detection pump with pressure transducer, flow meter, and manufacturer recommended spare parts for the pump controller and water level data collector will be maintained in the Mill warehouse to ensure that the pump and controller on either cell can be replaced and operational within 24 hours of detection of a failure of the pumping system. The root cause of the equipment failure will be documented in a report to Mill management with recommendations for prevention of are-occurrence. Slimes Drain System (i) A pump, Tsurumi Model # KTZ23.7-62 stainless steel, or equal, will be placed inside of the slimes drain access riser pipe of each cell and a near as possible to the bottom of the slimes drain sump. The bottom of the slimes drain sump in Cell 4A and Cell 4B are 38 and 35.9 feet below a water level measuring point, respectively, at the centerline of the slimes drain access pipe, near the ground surface level. Each pump discharge will be equipped with a 2 inch flow meter, E/H Model #33, or equal, that reads the pump discharge in gallons per minute, and records total gallons pumped. The flow rate and total gallons will be recorded by the Inspector on the weekly inspection form. Cii) The slimes drain pumps will be on adjustable probes that allow the pumps to be set to start and stop on intervals determined by Mill management. (iii)The Cell 4A and Cell 4B slimes drain pumps will be checked weekly to observe that they are operating and that the level probes are set properly, which is noted on the Weekly Tailings Inspection Form. If at any time either pump is observed to be not working properly, it will be repaired or replaced within 15 days; (iv)Depth to wastewater in the Cell 4A and Cell 4B slimes drain access riser pipes shall be monitored and recorded weekly to determine maximum and minimum fluid head before and after a pumping cycle, respectively. All head measurements must be made from the same measuring point, to the N'\Ce!l 4B\1nnuarv 2011 Submit!81~qnd Rcvi~ions for CcIl4mO&M Plan 01.10 I IICcll4A and4B 0 M Plen Rev 2 I -RedJjne.do~l~bmit~~JI-4~4 Plan 11 _11.1I1\GeIl4i'.a~ Plan CleaR ;!QHlIIQ3.dae Page 14 Ce1l4A BAT Monitoring, Operations and Maintenance Plan 1112010 Revision Denison 2·Ql nearest 0.01 foot. The results will be recorded as depth-in-pipe measurements on the Weekly Tailings Inspection Form; (v) On a monthly basis, each slimes drain pump will be turned off and the wastewater in the slimes drain access pipe will be allowed to stabilize for at least 90 hours. Once the water level has stabilized (based on no change in water level for three (3) successive readings taken no less than one (1) hour apart) the water level of the wastewater will be measured and recorded as a depth-in-pipe measurement on the Monthly Inspection Data form, by measuring the depth to water below the water level measuring point on the slimes drain access pipe; The slimes drain pumps for each cell will not be operated until Mill management has determined that no additional process solutions will be discharged to that cell, and the cell has been partially covered with the first phase of the reclamation cap. The long term effectiveness and performance of the slimes drain dewatering will be evaluated on the same basis as the currently operating slimes drain system for Cell 2. Tailings Emergencies Inspectors will notify the Radiation Safety Officer and/or Mill management immediately if, during their inspection, they discover that an abnormal condition exists or an event has occurred that could cause a tailings emergency. Until relieved by the Environmental or Radiation Technician or Radiation Safety Officer, inspectors will have the authority to direct resources during tailings emergencies. Any major catastrophic events or conditions pertaining to the tailings area should be reported immediately to the Mill Manager or the Radiation Safety Officer, one of whom will notify Corporate Management. If dam failure occurs, notify your supervisor and the Mill Manager immediately. The Mill Manager will then notify Corporate Management, MSHA (303-231-5465), and the State of Utah, Division of Dam Safety (801-538-7200). Ce1l4A Solution Freeboard Calculation The maximum tailings cell pond wastewater levels in Cells 1-1, Cell 2, Cell 3, CeIl4A, and Cell 4B are regulated by condition 10.3 of the White Mesa Mill l1e.(2) Materials License. Condition 10.3 states that "The FreellElImJ limit fer Celllsltsil be S61S.4 feet sbove meso sell leYel;-&IHHIJe fnebosf'd limit feF Cell 41. 8~1 4B 5hel~ iD-&eee-RJollee "'ith the flroee9ures set eut ill tbe latest edition of the Wbite-Mess Mill Tailings M8A&gem:e:ot-System snd l)isehftrge MittimiMtioll Technology (DMT) ~Ait9Fiflg Plftll 'lllIiefi.-is inchlded os s seetion of the Mill's Environmental N;\Ccl] 1B\Jnnunrv 20) I Submitmls and Revisions for <&1\4BIQ&M PIM 01.10. I I\Cell 4A od 4·B Q M Plan Rev 2 I -Redline.dooN;l,(;;eIl-4B\Novembe~llul~ IlREI RedsiollS for Cell 4BIO&M-Pl&n 1 1.1 l.IQ\CellAA 8nd-4~ PlaR CleaR 2Q1Q11Q3.aee Page 15 Cel14A BAT Monitoring, Operations and Maintenance Plan 1112010 Revision Denison 2·Ql Pretemao MeRuel. Said eeleulotieHs SMillie submitted as paFt ef t:he Attaua! Teeh&ieal E-.'ohmti&n RepeR. Sltid FepeFt shall be submitted fer Elleeuti'le SeeFetary optJf'6val fie later th1lH NO'leHlber lS ef eoeh )'eor.Freeboard limits. stonnwaler and wastewater management for the railings cells shall be detennined as follows: A. The freeboard limit for CellI shall be set annually in accordance with the procedures set out in Section 3.0 to Appendix E of the previously approved NRC license application. including the January 10, 1990 Drainage Report. Discharge of any surface water or wastewater from Cell I is expressly prohibited.!! B. The freeboard limit for Cells 3. 4A and 4B shall be recalculated annually in accordance with the procedures established by the Executive Secretary. Said calculations for freeboard limits shall be submitted as part of the Annual Technical Evaluation Report CATER), as described in Condition 12.3 below [of the licesnse and not included herein]. C. The clischarge of any surface water. stormwater. or wastewater from Cells 3. 4A. and 48 shall only be through an Executive Secretary authorized spiOway structure. [Applicable NRC Amendment:161 [Applicable UORC Amendment: 31 [Applicable UDRC Amendment:4] , The freeboard limits set out in Section 6.3 of the DMT Plan are intended to capture the Local 6-hour Probable Maximum Precipitation (PMP) event, which was detennined in the January 10, 1990 Drainage Report for the White Mesa site to be 10 inches. Based on the PMP storm event, the freeboard requirement for Cell 1 is a maximum operating water level of 5615.4 feet above mean sea level (amsl). The Cell 1 freeboard limit is not affected by operations or conditions in Cells 2, 3, 4A, or 4B. Cells 2 and 3 have no freeboard limit because those Cells are full or near full oftailings solids. Cell 4A has no freeboard limit because it is assumed that all precipitation falling on Cell 4A will overflow to Cell 4B. All precipitation falling on Cell 2, 3, and 4A and the adjacent drainage areas must be contained in Cell 4B. The flood volume from the PMP event over the Cell 2, 3, and Cell4A pond areas, plus the adjacent drainage areas, which must be contained in Cell 48, is 159.4 acre-feet of water. The flood volume from the PMP event over the Cell 4A area is 36 acre-feet of water (40 acres, plus the adjacent drainage area of 3 .25 acres, times the PMP of 10 inches). For the purposes of establishing the freeboard in Cell 4B, it is assumed Cell 4A has no freeboard limit and all of the flood volume from the PMP event will be contained in Ce1l4B. The flood volume from the PMP event over the Ce1l4B area is 38.l acre-feet of water (40 acres, plus the adjacent drainage area of 5.7 acres, times the PMP of 10 inches). This would result in a total flood volume of 197.5 acre-feet, including the 123.4 acre-feet of solution from Cells 2 and 3 and 36 acre-feet of solution from Cells 2, 3, and 4A that must N;\Co1l 4B\Januarv ZOI I Submittalsaod Revisions Cor Cc!l 4B\Q&M Plan 0 I. 10. I I\Cc!l 4A and 4B 0 M Plan Rev 2.1 -Redljne.dodl;\b~!1 ~B\Jole"em~llUm' . . "d 49 0 M PIEHl Clean ;!QHllIQ3.dee Page 16 Formatted: Outline numbered + Level: 6 + Numbering Style: A, B, C, ... + Start at: 1 + Alignment: Left + Aligned at: 1.15" + Tab after: 1.5" + Indent at: 1.5" Cell4A BAT Monitoring. Operations UJld Maintenance Plan J 1120JORevision Denison 2.01 be contained in Cell 48. The procedure for calculating the freeboard limit for Cell4B is set oUl in the DMT Plan. The Groundwater Quality Discharge Permit. 0.UGW370004, for the White Mesa Mill requires thatlhe minimum freeboard be no less than 3.0 feet for Cells I, 4A, and 4B bul based on License condition 10.3 and the procedure set out in the DMT Plan, the fi'eeboard limits for Cells I, 4A and 48 will be at leasl three feet. Figure 7, Hydraulic Pro'file Schematic, shows the relationship between the Cells and the relative elevations of the solution pools and the spillway elevations. The required freeboard for Cells 4A and 48 will be recalculated annually. N'\ccU 413\JanuDJY 2011 Subminols lind Revisions rQr Cell 4BIQ&M Plan 0 1.10.11\CcU 4A and 4B 0 M PI n Rev 2 J -Rcdlinc,dQcW:~1 4&\NoYemllef-SublllitlAl!Hl~ns-f~I-48\Q&M Phm 11.11.IQlCeJl ~ ... alJli.4B..G.-M ~1l201011Q3,dee Page 17 Cell 4A BAT Monitoring, Operations and Maintenance Plan 1112010 Revision Denison 2.()1 Attachments 1) Figures 1A and lB, Initial Filling Plan, Geosyntec Consultants 2) Figure 2A and 2B, Initial Filling Plan, Details and Sections, Geosyntec Consultants 3) Figure 3A and 3B, Initial Filling Plan, Solution and Slurry Pipeline Routes, Geosyntec Consultants 4) Figure 4A and 4B, Interim Filling Plan, Geosyntec Consultants 5) Figure 5, Leak Detection System Sumps for Cell 4A and 4B, Geosyntec Consultants 6) Figure 6A and 6B, Leak Detection Sump Operating Elevations, Geosyntec Consultants 7) Figure 7, Hydraulic Profile Schematic 8) Cell 4A and Cell 4B Freeboard Calculations 9) Table lA, Calculated Action leakage Rates for Various Head Conditions, Cell 4A, White Mesa Mill, Blanding, Utah, Geosyntec Consultants 10) Table 1B, Calculated Action leakage Rates for Various Head Conditions, Cell 4B, White Mesa Mill, Blanding, Utah, Geosyntec Consultants +---"\ Formatted: Tab stops: 4.99", Left 11) White Mesa Mill Tailings Management System and Discharge Minimization Technology (DMT) Monitoring Plan", 19/HI Re'oIisieA: DUSA 19, , eF eurreBtly IlJ3Pfe'JeEl .... ersiaR afthe DMT N;\Ccll mlJRHWyY 20' 1 Submjltals gnd Revisions for Cd' 4B\O&M Plan 0' 1O.11\Ce1l4A and 4B 0 M Plan Rev 2.1 -Redline.doc~!;'.Cell 4B\)l~I&l5-oRd R-e"iSiQA~ Iilr Cell 4B\Q&.H Plan Il.11.10\Gell 4"" BAd 49 0 H Phm ClelHl21lHll Hl3.dee Page 18 ~ " ."'" \ I -_. ,,600 --EXISTING GROUND CONTOUR -MAJOR EXISTING GROUND CONTOUR -MINOR --5590--PROPOSED SURFACE CONTOUR -MAJOR PROPOSED SURFACE CONTOUR -MINOR ~ -- LIMIT OF LINER SPLASH PAD HDPE PIPELINE SLURRY OR SOULTION SOLUTION RETURN SLIMES DRAIN "--c-'" ' , ~ 1 ~-r",,/ __ ) ' .... l ~ () 200' 400' L;;;;-' I Geosyntec () C:OnSllllants SCALE IN FEET INITIAL FILLING PLAN CELL4A BLANDING, UTAH DATE: OCTOBER 2010 PROJECT NO. SC0349 j FIGURE 1A L TSOfUllEll ,,-.... -.... ,./ ----r I , ==-=.. ~""::::'-- I I -J~~-I I " I -;;;;;---.., , , I , , :"""i::;- 6" OR S" HOPE PIPEUNE SLURRY OR SOLUTION I , " " / I I , r --:::----1. I ' I ' ..... ...:...::::-::.:0--I 'I ' J -_. I I I I I I I \ , I I I I , j -'" : /~~/ / ,.. / !JJJJ;;; / I I I I I I I I I I I I I I I I I \ , ------------ ' .... _---- ---------------------- --- ----------------------------------------.. -...... - ------------------------------------------------... _--------- --. REllJRN 1 LEGEND EXISl1NG GROUND CONTOUR -MAJOR EXISl1NG GROUND CONTOUR -MINOR --5590--PROPOSED SURFACE CONTOUR -MAJOR PROPOSED SURFACE CONTOUR -MINOR ------UMIT OF UNER == SPLASH PAD ---HOPE PIPELINE SLURRY OR SOUL 110N SOLU110N RETURN --------~ SLIMES DRAIN o 200' 400' \;;;M-' I SCALE IN FEET INITIAL FILLING PLAN CELL4B BLANDING, UTAH Geosyntecbl DATE: OCTOBER20'0 I FIGURE 18 consultants PROJECT NO SC0349 RETURN 8" HDPE PIPELINE SOLU1l0il: SLURRY OR SOLUTION " J , r ;' . '-. I , ./ .",.. . =----................ ---;;:-. ::::--............ / I A ..;;;t- : I / A I ~~ ..... ~ .... =---. ........ / I I I / / CREST Of SLOPE "$i 'i 60 WIL HOPE GEOIAE~BRANE (SIoIOO1t<) GEOS'INlI1ETIC etA Y UN'" WATERLINE ~1?5'N.r~~ . 4::::;'5 '11 LEGEND EXISTING GROUND CONTOUR -f.4AJOR EXISTING GROUND CONTOUR -f.4INOR --5590--PROPOSED SURFACE CONTOUR -MAJOR ----PROPOSED SURFACE CONTOUR -MINOR - - - - - -UMIT OF UNER ~ SPLASH PAD - . -HOPE PIPELINE SLURRY OR SOULTION VALVE • SOLUTION RETURN SLlf.4ES DRAIN ~ . JUMITS Of UN'" _ .................. -;;--.... =---1 ................ '-........ . I I I ! I I I I---\ _§g95~ o 100' ZOO' --- SCALE IN FEET INITIAL FILLING PLAN, DETAILS AND SECTIONS CELL4A BLANDING, UTAH T @ ~~PAD G C> 0: ;;;,~.s. eosyntec I DATE OCTOBER 2010 I consultan ts PROJECT NO. SC0349 FIGuRE 2A , I I I r , I I , I I I , , , I I I I , , I I • I , I , , I I , ~ SECllON \:=.J ~~~ PAD , , I I I , , I I , , , I I I I I I I I , , r I I , '.(MIN.> "NlllU~ 2d .. DE SlllIP OF C(QU£)OlAAI<E----'l W~1ERLJNE LEGEND EXISTING GROUND CONTOUR -MAJOR EXISllNG GROUND CONTOUR -MINOR --5590--PROPOSED SURFACE CONTOUR -MAJOR PROPOSED SURFACE CONTOUR -MINOR - - - - - -UMIT OF UNER t 222222221 SPLASH PAD • ~ HOPE PIPEUNE SLURRY OR SOUL llON -SOLUllON RETURN ---------SLIMES DRAIN 1 o 100· 200· t;;;-: I SCALE IN FEET INITIAL FILLING PLAN, DETAILS AND SECTIONS CELL4B BLANDING. UTAH Geosyntect> DhTE: OCTOBER 2010 F,GuRE ~I I consultants I PROJECT NO SCD349 I 28 SOLUTION RETURN ~~-----------------------..... , -- , \ 8" HDPE PIPELINE ~, / ~, I ~\ ':\ I ~ SOLUTION V RECLAIM , "BARGE , r, --~ \ \ "\ -0 \ \ ~ \ \ \~\J T \ \ \ \ \ \ , \ LEGEND EXlsnNG GROUND CONTOUR -~AJOR EXISllNG GROUND CONTOUR -MINOR --5590--PROPOSED SURFACE CONTOUR -MAJOR ----PROPOSED SURFACE CONTOUR -MINOR ~~ --.-- UMIT OF LINER SPLASH PAD HOPE PIPEUNE SLURRY OR SOUL 1l0N SOLUllON RETURN SUMES DRAIN SLURRY OR SOLUTION r \\ ~ \. '\ '\ \\ \. I. ~ o 100' 200· ----- SCALE I N FEET INITIAL FILLING PLAN, SOLUTION AND SLURRY PIPELINE ROUTES CELL4A BLANDING, UTAH 3A FlI3tlRE GeosyntecD ClJn~ultanl~ DATE: OCTOBER 2010 PROJECT NO SC0349 'i' SOlUTION 1It'N!l1I r -'-~' , .. -----., ,~ \~ ·1 \~ 6' aI e'" ~OP£ 1'1i'~E \ I, Sl.IJMY OR SQUI1lOfl ~ 'I , I \1 ,-\~ -------------- LEGEND ~STlNG GROUND CONTOUR -MAJOR EXISTING GROUND CONTOUR -MINOR --5590--PROPOSED SURFACE CONTOUR -MAJOR PROPOSED SURFACE CONTOUR -MINOR --- - --WAIT OF UNER fIZ;IIZ?)" SPLASH PAD , ____ HOPE PIPELINE SlURRY OR SOUlTION ... SOlUTION RETURN SUMES DRAIN I I I I I I I , I , , I '-, , VUMITS OF UNER -, , , , , I , , , , ~~ a 100' 200' W-' : SCALE IN FEET INITIAL FILLING PLAN, SOLUTION AND SLURRY PIPELINE ROUTES CELL4B BLANDING, UTAH FlGURE PROJECT NO, SC0349 38 Geosyntecbl DATE: OCTOBER2010 I consultants '",- / "r.,,--· .. ~<4~" ---.... ,/-' ~600 --EXISTING GROUND CONTOUR -MAJOR ----EXISTING GROUND CONTOUR -MINOR --S~90 --PROPOSED SURFACE CONTOUR -MAJOR ~ -- PROPOSED SURFACE CONTOUR -MINOR UMIT OF LINER SPLASH PAD HOPE PIPELINE SLURRY OR SOUL TlON SOLUTlON RETlJRN SLIMES DRAIN // 4', ..... -" ........... / \~ "'\ / ~ o 200' 400' ~' I SCALE IN FEET INITERIM FILLING PLAN CELL4A BLANDING, UTAH Geosyntec D DATE: OCTOBER 2010 consultants PROJECT NO. SC0349 FIGURE 4A ';;1 f! " --_, L ""lS CIi' U!'£R ." -=--: I ' I -,-r ~:...-==--r I ' I ~~. I I I I .... :::--: I J/ ;' " 't,' / -r:...-:::---==--.~ . I t I 6 --:;- I ~ I I I ' I .... ~. I I I I I - I \:\: I I " I I,' / I I I I I I I I I [ I I I I I I I I I I I I I \ , .. _---------- -----.... _-------------------------------- ' ... _---- ------------------------------------------------------------- --------------------- ~.". untw RElURN l LEGEND EXISl1NG GROUND CONTOUR MAJOR EXlSl1NG GROUNO CONTOUR -MINOR --5590--PROPOSED SURFACE CONTOUR -MAJOR PROPOSED SURfACE CONTOUR - - - - --UtoilT OF UNER I2=:zzzI SPLASH PAD MINOR ._-HDPE PIPEUNE SLURRY OR SOUL 11 ON SOLUTION RETURN SLIMES DRAIN o 200' 400' ~-' I SCALE IN FEET INTERIM FILLING PLAN CELL48 BLANDING, UTAH fiGURE 48 Geosyntect>1 DATE OCTOBER201 0 I consultants PROJECT NO. SC0349 22.5' ELBOW 18" II> SCHEDULE 40 PVC 60 MIL HDPE GEOMEMBRANE (TEXTURED) CUSHION GEOTEXTILE ./'"PREPARED SUBGRADE-/1 ' --~ .... ..( PUMP""/ SECTION LEAK DETECTION SYSTEM SUMP N_T.S, 1S"X6" REDUCER 6"X4" REDUCER LEAK DETECnON SYSTEM 4" ~ SCHEDULE 40 PVC 4" ~ SCHEDULE 40 PVC GEOSYNTHETIC CLAY LINER 60 MIL HDPE GEOMEMBRANE (SMOOTH) CUSHION GEOTEXTILE LEAK DETECT10N SYSTEM SUMP CELLS 4A AND 4B BLANDING, UTAH UA I ~: uCTOBER 2010 ~~ I Geo!~~~~l-i -PR-~-JE-CT-N-O.-SC0349 I V ~I S, ~ ~ ~ I PUMP· ON LEVEl.. ~;89 FEET MlSI u;,\I( PEl'E,C11ON SUMP El..EVAn~N: ~.64 FEET AMSI MAXIMUM S0LU110N ELEVATION.: 5556.14 Fm AMSI I,.QWEST IIOI..UTlON aEYATION: l!55S.14 FEET AMir I.l!AK DETECTION SUMP CELI,.':A BtAN.D1NG. lJTAH ~1e ~·ao10 flGURE i 1 Geosyntec (>1 1 COtllIUltnnts ~NO. SC03'I9 OJ-\ XI MAXIMUM SOLUTION ELEVATION: 5558.5 FEET AMSI --.--.--.----_. __ .-_._- PUMP ON LEVEL 5557.69 FEET AMSI ---. - -• -- LEAK DETECnON SUMP ELEVATION: 6555.44 FEET AMSI LOWEST SOLUnON ELEVAnON: 5557.5 FEET AMSI LEAK DETEcnON SUMP CELL4B BLANDING. UTAH Geosyntec t> amsultants DATE: OCTOBER 2010 PROJECT NO. SC0349 FIGURE 68 PMP VOLUME 38.1 AC-FT. PLUS 159.40 AC-FT FROM CELLS -, • I • 2,3,AND4A TOTAL 1.97.50 AC-FT CELL4B FREEBOARD LIMIT 55!M.64 FT. MSL PMPVOLUME,36AC-FT. PLUS 123.4 AC-FT FROM CELL 2 AND CELL 3 159.40 AC-FT OVERFLOWS TO CELL4B PMP VOLUME, 123.4 AC-Fr OVERFLOWS TO CELL 4A NOT TO SCALE HYDRAULIC PROFILE SCHEMATIC CELL4B Geosyntec E> consultants BLANDING, UTAH DATE: OCTOBER 2010 PROJECT NO. SC0349 AGURE 7 Geosyntec Consultants Table 1A Calculated Action Leakage Rates for Various Head Conditions Cel14A, White Mesa Mill Blanding, Utah Head Above Liner Calculated Action Leakage Rate System (feet) (gallons/aue/day) 5 222.04 10 314.0 15 384.58 20 444.08 25 496.5 30 543.88 35 587.5 37 604.0 Geosyntec Consultants Table 16 Calculated Action leakage Rates for Various Head Conditions Cell 46, White Mesa Mill Blanding, Utah Head Above Liner System Calculated Action Leakage Rate (feet) (gallons/acre/day) 5 211.4 10 317.0 15 369.9 20 422.7 25 475.6 30 528.4 3S 570.0 37 581.2 01 /2011 Revision Denison 2.1 Cell 4A and 4B BAT Monitoring, Operations and Maintenance Plan. Introduction Construction of Cell 4A was authorized by the Utah Department of Environmental Quality, Division of Radiation Control ("ORC) on June 25, 2007. The construction authorization provided that Cell 4A shall not be in operation until after a BAT Monitoring, Operations and Maintenance Plan is submitted for Executive Secretary review and approval. The Plan shall include requirements in Part I.F.3 of the Groundwater Discharge Permit No. UGW370004 ("GWDP") and fulfill the requirements of Parts I.D.6, I.E.8, and I.F.9 of the GWDP. Construction ofCe1l4B was authorized by DRC on June 21, 2010. The construction authorization provided that Cell 4 B shall not be in operation until after a BA T Monitoring, Operations and Maintenance Plan is submitted for Executive Secretary review and approval. The Plan shall include requirements in Part I.F.3 of the GWDP and fulfill the requirements of Parts I.D.12, I.E. 12, and I.F.9 of the GWDP Cell Design Tailings Ce1l4A consists of the following major elements: a) Dikes -consisting of earthen embankments of compacted soil, constructed between 1989-1990, and composed of four dikes, each including a IS-foot wide road at the top (minimum). On the north, east, and south margins these dikes have slopes of 3H to 1 V. The west dike has an interior slope of 2H to 1 V. Width of these dikes varies; each has a minimum crest width of at least 15 feet to support an access road. Base width also varies from 89-feet on the east dike (with no exterior embankment), to 211-feet at the west dike. b) Foundation -including sub grade soils over bedrock materials. Foundation preparation included excavation and removal of contaminated soils, compaction of imported soils to a maximum dry density of 90%. Floor of Cell 4A has an average slope of 1 % that grades from the northeast to the southwest corners. c) Tailings Capacity -the floor and inside slopes of Cell 4A encompass about 40 acres and have a maximum capacity of about 1.6 million cubic yards of tailings material storage (as measured below the required 3-foot freeboard). d) Liner and Leak Detection Systems -including the following layers, in descending order: 1) Primary Flexible Membrane Liner (FML) -consisting of impermeable 60 mil high density polyethylene (HDPE) membrane that extends across both N:\Ce1l4BVanuary 2011 Submittals and Revisions for Ce114B\O&M Plan 01.10.11\Ce1l4A and 4B 0 M Plan Rev 2.1 -clean. doc Page 1 01/2011 Revision Denison 2.1 the entire cell floor and the inside side-slopes, and is anchored in a trench at the top of the dikes on all four sides. The primary FML will be in direct physical contact with the tailings material over most of the Ce1l4A floor area. In other locations, the primary FML will be in contact with the slimes drain collection system (discussed below). N:\Ccll 4B\.Ianllary 20 II llbmittnls ru1d Revi ions for Ce ll 4B\O&M Plan 01.1 O.II\Cell 4A and 480 M Plan Rcv 2.1 -clean.doe Page 2 Ce1l4A BAT Monitoring, Operations and Maintenance Plan 1112010 Revision Denison 2.1 2) Leak Detection System -includes a permeable HDPE geonet fabric that extends across the entire area under the primary FML in Cell 4A, and drains to a leak detection sump in the southwest corner. Access to the leak detection sump is via an I8-inch inside diameter (ID) PVC pipe placed down the inside slope, located between the primary and secondary FML liners. At its base this pipe will be surrounded with a gravel filter set in the leak detection sump, having dimensions of 10 feet by 10 feet by 2 feet deep. In turn, the gravel filter layer will be enclosed in an envelope of geotextile fabric. The purpose of both the gravel and geotextile fabric is to serve as a filter. 3) Secondary FML -consisting of an impermeable 60-mil HDPE membrane found immediately below the leak detection geonet. Said FML also extends across the entire Cell 4A floor, up the inside side-slopes and is also anchored in a trench at the top of all four dikes. 4) Geosynthetic Clay Liner -consisting of a manufactured geosynthetic clay liner (GCL) composed of O.2-inch of low permeability bentonite clay centered and stitched between two layers of geotextile. Prior to disposal of any wastewater in Cell 4A, the Permittee shall demonstrate that the GCL has achieved a moisture content of at least 50% by weight. This item is a revised requirement per DRC letter to DUSA dated September 28,2007 e) Slimes Drain Collection System -including a two-part system of strip drains and perforated collection pipes both installed immediately above the primary FML, as follows: I) Horizontal Strip Drain System -is installed in a herringbone pattern across the floor of Cell 4A that drain to a "backbone" of perforated collection pipes. These strip drains are made of a prefabricated two-part geo-composite drain material (solid polymer drainage strip) core surrounded by an envelope of non-woven geotextile filter fabric. The strip drains are placed immediately over the primary FML on 50-foot centers, where they conduct fluids downgradient in a southwesterly direction to a physical and hydraulic connection to the perforated slimes drain collection pipe. A series of continuous sand bags, filled with filter sand cover the strip drains. The sand bags are composed of a woven polyester fabric filled with well graded filter sand to protect the drainage system from plugging. 2) Horizontal Slimes Drain Collection Pipe System -includes a "backbone" piping system of 4-inch ID Schedule 40 perforated PVC slimes drain collection (SDC) pipe found at the downgradient end of the strip drain lines. This pipe is in turn overlain by a berm of gravel that runs the entire diagonal length of the cell, surrounded by a geotextile fabric cushion in immediate contact with the primary FML. The non-woven geotextile material is overlain at the surface by a woven geotextile fabric, which is ballasted laterally by sandbags on each side of the backbone of the berm. N:\Ce1l4B\January 2011 Submittals and Revisions for Ce1l4B\O&M Plan 01.10.ll\Ce1l4A and 4B 0 M Plan Rev 2.1 -clean.doc Page 3 Ce1l4A BAT Monitoring, Operations and Maintenance Plan 11/2010 Revision Denison 2.1 In turn, the gravel is overlain by a layer of non-woven geotextile to serve as an additional filter material. This perforated collection pipe serves as the "backbone" to the slimes drain system and runs from the far northeast corner downhill to the far southwest corner of Cell 4A where it joins the slimes drain access pipe. 3) Slimes Drain Access Pipe -consisting of an I8-inch ID Schedule 40 PVC pipe placed down the inside slope of Cell 4A at the southwest corner, above the primary FML. Said pipe then merges with another horizontal pipe of equivalent diameter and material, where it is enveloped by gravel and nonwoven geotextile that serves as a cushion to protect the primary FML. The non-woven geotextile material is overlain at the surface by a woven geotextile fabric, which is ballasted by sandbags.A reducer connects the horizontal I8-inch pipe with the 4-inch SDC pipe. At some future time, a pump will be set in this 18-inch pipe and used to remove tailings wastewaters for purposes of de-watering the tailings cell. f) Dike Splash Pads - A minimum of eight (8) 20-foot wide splash pads are installed on the interior dike slopes to protect the primary FML from abrasion and scouring by tailings slurry. These pads consist of an extra layer of 60 mil HDPE membrane that is placed down the inside slope of Cell 4A, from the top of the dike and down the inside slope. The pads extend to a point 5-feet beyond the toe of the slope to protect the liner bottom during initial startup of the Cell. The exact location of the splash pads is detailed on the As-Built Plans and Specifications. g) Rub Protection Sheets -In addition to the splash pads described in f) above, rub sheets are installed beneath all piping entering or exiting Cell 4A that is not located directly on the splash pads. h) Emergency Spillway - a concrete lined spillway constructed near the western corner of the north dike to allow emergency runoff from Cell 3 into Cell 4A. This spillway will be limited to a 6-inch reinforced concrete slab set directly over the primary FML in a 4-foot deep trapezoidal channel. A second spillway has been constructed in the southwest corner of Cell 4A to allow emergency runoff from Cell 4A into Cell 4B. All stormwater runoff and tailings wastewaters not retained in Cells 3 and 4A, will be managed and contained in Cell 4B, including the Probable Maximum Precipitation and flood event. Tailings Cell4B consists of the following major elements: a) Dike -consisting of a newly-constructed dike on the south side of the cell with a IS-foot wide road at the top (minimum) to support an access road. The grading plan for the Cell 4B excavation includes interior slopes of 2H to IV. The exterior slope of the southern dike will have the typical slopes of 3H to IV. Limited portions of the Cell 4B interior sideslopes in the northwest corner and southeast corner of the cell (where the slimes drain and leak detection sump will be located) will also have a slope of 3H to N :\Ce1l4B\January 2011 Submittals and Revisions for Ce1l4B\O&M Plan 01.10.II\Ce1l4A and 4B 0 M Plan Rev 2.1 -clean.doc Page 4 Cell 4A BAT Monitoring, Operations and Maintenance Plan 11120 I 0 Revision Denison 2.1 1 V. The base width of the southern dike varies from approximately 100 feet at the western end to approximately 190 feet at the eastern end of the dike, with no exterior embankment present on any other side of the cell. b) Foundation -including subgrade soils over bedrock materials. Foundation preparation included 6-inch over excavation of rock and placement and compaction of imported soils to a maximum dry density of 90% at a moisture content between +3% and -3% of optimum moisture content, as determined by ASTM D-1557. The floor of Cell 4B has an average slope of 1 % that grades from the northwest corner to the southeast comer. c) Tailings Capacity -the floor and inside slopes of Cell 4B encompass about 45 acres and the cell will have a water surface area of 40 acres and a maximum capacity of about 1.9 million cubic yards of tailings material storage (as measured below the required 3-foot freeboard). d) Liner and Leak Detection Systems -including the following layers, in descending order: 1) Primary Flexible Membrane Liner (FML) -consisting of 60 mil high density polyethylene (HDPE) membrane that extends across both the entire cell floor and the inside side-slopes, and is anchored in a trench at the top of the dikes on all four sides. The primary FML will be in direct physical contact with the tailings material over most of the Cell 4B floor area. In other locations, the primary FML will be in contact with the slimes drain collection system (discussed below). 2) Leak Detection System -includes a permeable HDPE geonet fabric that extends across the entire area under the primary FML in Cell 4B, and drains to a leak detection sump in the southeast corner. Access to the leak detection sump is via a 2-foot inside diameter (ID) PVC pipe placed down the inside slope, located between the primary and secondary FML liners. At its base this pipe will be surrounded with a gravel filter set in the leak detection sump, having dimensions of 10 feet by 10 feet by 2 feet deep. In turn, the gravel filter layer will be enclosed in an envelope of geotextile fabric. The purpose of both the gravel and geotextile fabric is to serve as a filter. 3) Secondary FML -consisting of a 60-mil HDPE membrane found immediately below the leak detection geonet. Said FML also extends across the entire Cell 4B floor, up the inside side-slopes and is also anchored in a trench at the top of all four dikes. 4) Geosynthetic Clay Liner -consisting of a manufactured geosynthetic clay liner (GCL) composed of O.2-inch of low permeability bentonite clay centered and stitched between two layers of geotextile. Prior to disposal of any wastewater in Cell 4B, the Permittee shall demonstrate that the GCL has achieved a moisture content of at least 50% by weight. e) Slimes Drain Collection System -including a two-part system of strip drains and perforated collection pipes both installed immediately above N:\Ce1l4B\January 2011 Submittals and Revisions for Ce1l4B\O&M Plan 01.10. I I\Ce1l4A and 4B 0 M Plan Rev 2.1 -clean. doc Page 5 Cell 4A BAT Monitoring, Operations and Maintenance Plan the primary FML, as follows: 1112010 Revision Denison 2.1 1) Horizontal Strip Drain System -is installed in a herringbone pattern across the floor of Cell 4B that drain to a "backbone" of perforated collection pipes. These strip drains are made of a prefabricated two-part geo-composite drain material (solid polymer drainage strip) core surrounded by an envelope of non-woven geotextile filter fabric. The strip drains are placed immediately over the primary FML on 50-foot centers, where they conduct fluids downgradient in a southeasterly direction to a physical and hydraulic connection to the perforated slimes drain collection pipe. A series of continuous sand bags, filled with ftlter sand cover the strip drains. The sand bags are composed of a woven polyester fabric filled with well graded filter sand to protect the drainage system from plugging. 2) Horizontal Slimes Drain Collection Pipe System -includes a "backbone" piping system of 4-inch ID Schedule 40 perforated PVC slimes drain collection (SDC) pipe found at the downgradient end of the strip drain lines. This pipe is in turn overlain by a berm of gravel that runs the entire diagonal length of the cell, surrounded by a geotextile fabric cushion in immediate contact with the primary FML. In turn, the gravel is overlain by a layer of non-woven geotextile to serve as an additional filter material. The non-woven geotextile material is overlain at the surface by a woven geotextile fabric, which is ballasted by sandbags. This perforated collection pipe serves as the "backbone" to the slimes drain system and runs from the far northwest corner downhill to the far southeast corner of Ce1l4B where it joins the slimes drain access pipe. 3) Slimes Drain Access Pipe -consisting of an 18-inch ID Schedule 40 PVC pipe placed down the inside slope of Cell 4B at the southeast corner, above the primary FML. Said pipe then merges with another horizontal pipe of equivalent diameter and material, where it is enveloped by gravel and non-woven geotextile that serves as a cushion to protect the primary FML. The non-woven geotextile material is overlain at the surface by a woven geotextile fabric, which is ballasted laterally by sandbags on each side of the backbone of the berm. A reducer connects the horizontal 18- inch pipe with the 4-inch SDC pipe. At some future time, a pump will be set in this 18-inch pipe and used to remove tailings wastewaters for purposes of de-watering the tailings cell. f) Ce1l4B North and East Dike Splash Pads -Nine 20-foot-wide splash pads will be constructed on the north and east dikes to protect the primary FML from abrasion and scouring by tailings slurry. These pads will consist of an extra layer of textured, 60 mil HDPE membrane that will be installed in the anchor trench and placed down the inside slope of Cell 4B, from the top of the dike, under the inlet pipe, and down the inside slope to a point at least 5 feet onto the Cell4B floor beyond the toe of the slope. g) Rub Protection Sheets -In addition to the splash pads described in f) N:\Ce1l4BVanuary 2011 Submittals and Revisions for Ce1l4B\O&M Plan 01.10.11\Ce1l4A and 4B 0 M Plan Rev 2.1 -clean. doc Page 6 Cell4A BAT Monitoring, Operations and Maintenance Plan 11/2010 Revision Denison 2.1 above, rub sheets are installed beneath all piping entering or exiting Cell 4B that is not located directly on the splash pads. h) Emergency Spillway - a concrete lined spillway constructed near the southern corner of the east dike to allow emergency runoff from Cell 4A into Cell 4B. This spillway will be limited to a 6-inch reinforced concrete slab, with a welded-wire fabric installed within its midsection, set atop a cushion geotextile placed directly over the primary FML in a 4-foot deep trapezoidal channel. A 100 foot wide, 60 mil HDPE geomembrane splash pad will be installed beneath the emergency spillway. No other spillway or overflow structure will be constructed at Cell 4B. All stormwater runoff and tailings wastewaters not retained in Cells 2, 3 and 4A, will be managed and contained in Cell 4B, including the Probable Maximum Precipitation and flood event. Cell Operation Solution Discharge to Cell 4A Cell 4A will initially be used for storage and evaporation of process solutions from the Mill operations. These process solutions will be from the uranium/vanadium solvent extraction circuit, or transferred from Cell 1 evaporation pond or the free water surface from Cell 3, or transferred from Cell 2 tailings dewatering operations. The solution will be pumped to Cell4A through 6 inch or 8 inch diameter HDPE pipelines. The initial solution discharge will be in the southwest corner of the Cell. The solution will be discharged in the bottom of the Cell, away from any sand bags or other installation on the top of the FML. Building the solution pool from the low end of the Cell will allow the solution pool to gradually rise around the slimes drain strips, eliminating any damage to the strip drains or the sand bag cover due to solution flowing past the drainage strips. The solution will eventually be discharged along the dike between Cell 3 and Ce1l4A, utilizing the Splash Pads described above. The subsequent discharge of process solutions will be near the floor of the pond, through a discharge header designed to discharge through multiple points, thereby reducing the potential to damage the Splash Pads or the Slimes Drain system. At no time, subsequent to initial filling, will the solution be discharged into less than 2 feet of solution. As the cell begins to fill with solution the discharge point will be pulled back up the Splash Pad and allowed to continue discharging at or near the solution level. Solution Discharge to Ce1l4B Cell 4B will initially be used for storage and evaporation of process solutions from the Mill operations. These process solutions will be from the uranium/vanadium solvent extraction circuit, or transferred from Cell 1 evaporation pond or the free water surface from Cell 3 or Cell 4A, or transferred from Cell 2 dewatering operations. The solution will be pumped to Cell 4B through 6 inch or 8 inch diameter HDPE pipelines. The initial solution discharge will be in the southeast corner of the Cell. The discharge pipe will be routed N:\Celi 4B\January 2011 Submittals and Revisions for CeI14B\O&M Plan 01.10.11 \Cell 4A and 4B 0 M Plan Rev 2.1 -clean.doc Page 7 Cell 4A BAT Monitoring, Operations and Maintenance Plan 1112010 Revision Denison 2.1 down the Splash Pad provided in the southeast corner of the Cell at the spillway to protect the primary FML. The solution will be discharged in the bottom of the Cell, away from any sand bags or other installation on the top of the FML. Building the solution pool from the low end of the Cell will allow the solution pool to gradually rise around the slimes drain strips, eliminating any damage to the strip drains or the sand bag cover due to solution flowing past the drainage strips. The solution will eventually be discharged along the dike between Cell 3 and Cell4B, utilizing the Splash Pads described above. The subsequent discharge of process solutions will be near the floor of the pond, through a discharge header designed to discharge through multiple points, thereby reducing the potential to damage the Splash Pads or the Slimes Drain system. At no time, subsequent to initial filling, will the solution be discharged into less than 2 feet of solution. As the cell begins to fill with solution the discharge point will be pulled back up the Splash Pad and allowed to continue discharging at or near the solution level. Initial Solids Discharge into Cell 4A Once Cell 4A is needed for storage for tailings solids the slurry discharge from No.8 CCD thickener will be pumped to the cell through 6 inch or 8 inch diameter HDPE pipelines. The pipelines will be routed along the dike between Cell 3 and Ce1l4A, with discharge valves and drop pipes extending down the Splash Pads to the solution level. One or all of the discharge points can be used depending on operational considerations. Solids will settle into a cone, or mound, of material under the solution level, with the courser fraction settling out closer to the discharge point. The initial discharge locations are shown on Figure IA. Figure 2A illustrates the general location of the solution and slurry discharge pipelines and control valve locations. The valves are 6" or 8" stainless steel knife-gate valves. The initial discharge of slurry will be at or near the toe of the Cell slope and then gradually moved up the slope, continuing to discharge at or near the water surface. This is illustrated in Section A-A on Figure 2A. Because of the depth of Cell 4A, each of the discharge points will be utilized for an extended period of time before the cone of material is above the maximum level of the solution. The discharge location will then be moved further to the interior of the cell allowing for additional volume of solids to be placed under the solution level. The solution level in the cell will vary depending on the operating schedule of the Mill and the seasonal evaporation rates. The tailings slurry will not be allowed to discharge directly on to the Splash Pads, in order to further protect the FML. The tailings slurry will discharge directly in to the solution contained in the Cell, onto an additional protective sheet, or on to previously deposited tailings sand. Initial Solids Discharge into Ce1l4B Once Cell 4B is needed for storage for tailings solids the slurry discharge from No.8 CCD thickener will be pumped to the cell through 6 inch or 8 inch diameter HDPE pipelines. The pipelines will be routed along the dike between Cell 3 and Cell4B, with discharge valves and drop pipes extending down the Splash Pads to N:\Ce1l4B\January 2011 Submittals and Revisions for CeIl4B\O&M Plan 01.10.II\CeIl4A and 4B 0 M Plan Rev 2.1 -clean. doc Page 8 Ce1l4A BAT Monitoring, Operations and Maintenance Plan 11/2010 Revision Denison 2.1 the solution level. One or all of the discharge points can be used depending on operational considerations. Solids will settle into a cone, or mound, of material under the solution level, with the courser fraction settling out closer to the discharge point. The initial discharge locations are shown on Figure lB. Figure 2B illustrates the general location of the solution and slurry discharge pipelines and control valve locations. The valves are 6" or 8" stainless steel knife-gate valves. The initial discharge of slurry will be at or near the toe of the Cell slope and then gradually moved up the slope, continuing to discharge at or near the water surface. This is illustrated in Section A-A on Figure 2B. Because of the depth of Cell 4B, each of the discharge points will be utilized for an extended period of time before the cone of material is above the maximum level of the solution. The discharge location will then be moved further to the interior of the cell allowing for additional volume of solids to be placed under the solution level. The solution level in the cell will vary depending on the operating schedule of the Mill and the seasonal evaporation rates. The tailings slurry will not be allowed to discharge directly on to the Splash Pads, in order to further protect the FML. The tailings slurry will discharge directly in to the solution contained in the Cell, onto an additional protective sheet, or on to previously deposited tailings sand. Equipment Access to Ce1l4A and Ce1l4B Access will be restricted to the interior portion of the cells due to the potential to damage the flexible membrane liners. Only low pressure rubber tired all terrain vehicles or foot traffic will be allowed on the flexible membrane liners. Personnel are also cautioned on the potential damage to the flexible membrane liners through the use and handling of hand tools and maintenance materials. Reclaim Water System at Ce1l4A A pump barge and solution recovery system is operating in the southwest comer of the cell to pump solution from the cell for water balance purposes or for re-use in the Mill process. Figure 3A illustrates the routing of the solution return pipeline and the location of the pump barge. The pump barge will be constructed and maintained to ensure that the flexible membrane liner is not damaged during the initial filling of the cell or subsequent operation and maintenance activities. The condition of the pump barge and access walkway will be noted during the weekly Cell inspections. Reclaim Water System at Cell4B A pump barge and solution recovery system will be installed in the southeast comer of the cell to pump solution from the cell for water balance purposes or for re-use in the Mill process. Figure 3B illustrates the routing of the solution return pipeline and the location of the pump barge. The pump barge will be constructed and maintained to ensure that the flexible membrane liner is not damaged during N:\CeI14B\January 2011 Submittals and Revisions for Ce114B\O&M Plan 01.10.11\Ce114A and 4B 0 M Plan Rev 2.1 -clean. doc Page 9 Ce1l4A SAT Monitoring, Operations and Maintenance Plan 1112010 Revision Denison 2.1 the initial filling of the cell or subsequent operation and maintenance activities. The condition of the pump barge and access walkway will be noted during the weekly Cell inspections. Interim Solids Discharge to Cell 4A Figure 4A illustrates the progression of the slurry discharge points around the north and east sides of Cell 4A. Once the tailings solids have been deposited along the north and east sides of the Cell, the discharges points will subsequently be moved to the sand beaches, which will eliminate any potential for damage to the liner system. Interim Solids Discharge to Cell4B Figure 4B illustrates the progression of the slurry discharge points around the north and east sides of Cell 4B. Once the tailings solids have been deposited along the north and east sides of the Cell, the discharges points will subsequently be moved to the sand beaches, which will eliminate any potential for damage to the liner system. Liner Maintenance and QAlQC for Cell 4A Any construction defects or operational damage discovered during observation of the flexible membrane liner will be repaired, tested and documented according to the procedures detailed in the approved Revised Construction Quality Assurance Plan for the Construction of the Cell 4A Lining System, May 2007, by GeoSyntec Consultants. Liner Maintenance and QA/QC for Ce1l4B Any construction defects or operational damage discovered during observation of the flexible membrane liner will be repaired, tested and documented according to the procedures detailed in the approved Construction Quality Assurance Plan for the Construction of the Cell 4B Lining System, October 2009, by Geosyntec Consultants. BAT Performance Standards for Tailings Cell 4A and 4B DUSA will operate and maintain Tailings Ce1l4A and 4B so as to prevent release of wastewater to groundwater and the environment in accordance with this BAT Monitoring Operations and Maintenance Plan, pursuant to Part I.H.8 of the GWDP. These performance standards shall include: N:\Ce1l4B\January 2011 Submittals and Revisions for Ce1l4B\O&M Plan 01.l0.II\Ce1l4A and 4B 0 M Plan Rev 2.1 -clean.doc Page 10 Cell 4A BAT Monitoring, Operations and Maintenance Plan 1112010 Revision Denison 2.1 1) Leak Detection System Pumping and Monitoring Equipment -the leak detection system pumping and monitoring equipment in each cell includes a submersible pump, pump controller, water level indicator (head monitoring), and flow meter with volume totalizer. The pump controller is set to maintain the maximum level in the leak detection system in each cell at no more than 1 foot above the lowest level of the secondary flexible membrane, not including the sump. A second leak detection pump with pressure transducer, flow meter, and manufacturer recommended spare parts for the pump controller and water level data collector is maintained in the Mill warehouse to ensure that the pump and controller can be replaced and operational within 24 hours of detection of a failure of the pumping system. The root cause of the equipment failure will be documented in a report to Mill management with recommendations for prevention of are-occurrence. 2) Maximum Allowable Head -the Permittee shall measure the fluid head above the lowest point on the secondary flexible membrane in each cell by the use of procedures and equipment specified in the White Mesa Mill Tailings Management System and Discharge Minimization Technology (DMT) Monitoring Plan, 10/10 Revision: Denison-l0.2, or the currently approved DMT Plan. Under no circumstance shall fluid head in the leak detection system sump exceed a 1-foot level above the lowest point in the lower flexible membrane liner, not including the sump. 3) Maximum Allowable Daily LDS Flow Rates -the Permittee shall measure the volume of all fluids pumped from each LDS on a weekly basis, and use that information to calculate an average volume pumped per day. Under no circumstances shall the daily LDS flow volume exceed 24,160 gallons/day for Ce1l4A or 26,145 gallons/day for Cell 4B. The maximum daily LDS flow volume will be compared against the measured cell solution levels detailed on the attached Table 1A or 1B for Cells 4A or 4B, respectively, to determine the maximum daily allowable LDS flow volume for varying head conditions in the cell. 4) 3-foot Minimum Vertical Freeboard Criteria -the Permittee shall operate and maintain wastewater levels to provide a 3-foot Minimum of vertical freeboard in Tailings Ce1l4A and Ce1l4B. Said measurements shall be made to the nearest 0.1 foot. 5) Slimes Drain Recovery Head Monitoring -immediately after the Permittee initiates pumping conditions in the Tailings Cell4A or Cell 4B slimes drain system, monthly recovery head tests and fluid level measurements will be made in accordance with a plan approved by the DRC Executive Secretary. The slimes drain system pumping and monitoring equipment, includes a submersible pump, pump controller, water level indicator (head monitoring), and flow meter with volume N:\Ce1l4B\January 2011 Submittals and Revisions for Ce1l4B\O&M Plan 01.10.ll\CeU4A and 4B 0 M Plan Rev 2.1 • clean.doc Page 11 Ce1l4A BAT Monitoring, Operations and Maintenance Plan totalizer. Routine Maintenance and Monitoring 11/2010 Revision Denison 2.1 Trained personnel inspect the White Mesa tailings system on a once per day basis. Any abnormal occurrences or changes in the system will be immediately reported to Mill management and maintenance personnel. The inspectors are trained to look for events involving the routine placement of tailings material as well as events that could affect the integrity of the tailings cell dikes or lining systems. The daily inspection reports are summarized on a monthly basis and reviewed and signed by the Mill Manager. Solution Elevation Measurements of solution elevation in Ce1l4A and Ce1l4B are to be taken by survey on a weekly basis, and measurements of the beach area in Ce1l4A and Cell 4B with the highest elevation are to be taken by survey on a monthly basis, by the use of the procedures and equipment specified in the latest approved edition of the DMT Plan. Leak Detection System The Leak Detection System in Cell 4A and Cell 4B is monitored on a continuous basis by use of a pressure transducer that feeds water level information to an electronic data collector. The water levels are measured every hour and the information is stored for later retrieval. The water levels are measured to the nearest 0.10 inch. The data collector is currently programmed to store 7 days of water level information. The number of days of stored data can be increased beyond 7 days if needed. The water level data is downloaded to a laptop computer on a weekly basis and incorporated into the Mill's environmental monitoring data base, and into the files for weekly inspection reports of the tailings cell leak detection systems. Within 24 hours after collection of the weekly water level data, the information will be evaluated to ensure that: 1) the water level in the Cell 4A and Cell 4B leak detection sumps did not exceed the allowable level (5556.14 feet amsl in the Cell 4A LDS sump and 5558.5 feet amsl in the Cell4B sump), and 2) the average daily flow rate from the LDS did not exceed the maximum daily allowable flow rate at any time during the reporting period. For Cell 4A and Cell 4B, under no circumstance shall fluid head in the leak detection system sump exceed a I-foot level above the lowest point in the lower flexible membrane liner, not including the sump. To determine the Maximum Allowable Daily LDS Flow Rates in the Cell 4A and Cell 4B leak detection system, the total volume of all fluids pumped from the LDS of each cell on a weekly basis shall be recovered from the data collector, and that information will N:\Cell 4B\January 2011 Submittals and Revisions for CeIl4B\O&M Plan 01.10.11 \Cell 4A and 4B 0 M Plan Rev 2.1 -clean. doc Page 12 Ce1l4A BAT Monitoring, Operations and Maintenance Plan 11 /2010 Revision Denison 2.1 be used to calculate an average volume pumped per day for each cell. Under no circumstances shall the daily LDS flow volume exceed 24,160 gallons/day from Cell 4A or 26,145 gallons/day from Cell 4B. The maximum daily LDS flow volume will be compared against the measured cell solution levels detailed on the attached Tables lA and 1B, to determine the maximum daily allowable LDS flow volume for varying head conditions in Cell 4A and Cell 4B. Any abnormal or out of compliance water levels must be immediately reported to Mill management. The data collector on each cell is also equipped with an audible alarm that sounds if the water level in the leak detection sump exceeds the allowable level (5556.14 feet amsl in the Cell 4A LDS sump and 5558.5 feet amsl in the Cell 4B sump). The current water level is displayed at all times on each data collector and available for recording on the daily inspection form. Each leak detection system is also equipped with a leak detection pump, EPS Model # 25S05-3 stainless steel, or equal. Each pump is capable of pumping in excess of 25 gallons per minute at a total dynamic head of 50 feet. Each pump has a 1.5 inch diameter discharge, and operates on 460 volt 3 phase power. Each pump is equipped with a pressure sensing transducer to start the pump once the level of solution in the leak detection sump is approximately 2.25 feet (elevation 5555.89 in the Cell 4A LDS sump and 5557.69 feet amsl in the Cell4B sump) above the lowest level of the leak detection sump (9 inches above the lowest point on the lower flexible membrane liner for Cell 4A and 3 inches for Cell 4B), to ensure the allowable 1.0 foot (5556.14 feet amsl in the Cell4A LDS sump and 5558.5 feet amsl in the Cell 4B sump) above the lowest point on the lower flexible membrane liner is not exceeded). The attached Figures 6A and 6B (Cell 4A and 4B, respectively), Leak Detection Sump Operating Elevations, illustrates the relationship between the sump elevation, the lowest point on the lower flexible membrane liner and the pump-on solution elevation for the leak detection pump. The pump also has manual start and stop controls. The pump will operate until the solution is drawn down to the lowest level possible, expected to be approximately 4 inches above the lowest level of the sump (approximate elevation 5554.0 and 5555.77 ft amsl for Cells 4A and 4B, respectively). The pump discharge is equipped with a 1.5 inch flow meter, EPS Paddle Wheel Flowsensor, or equal, that reads the pump discharge in gallons per minute, and records total gallons pumped. The flow rate and total gallons are recorded by the Inspector on the weekly inspection form. The leak detection pump is installed in the horizontal section of the 18 inch, perforated section of the PVC collection pipe. The distance from the top flange face, at the collection pipe invert, to the centerline of the 22.5 degree elbow is 133.4 feet in Cell 4A and 135.6 feet in Cell 4B, and the vertical height is approximately 45 feet in Ce1l4A and approximately 42.5 feet in Cell 4B. The pump is installed at least 2 feet beyond the centerline of the elbow. The bottom of the pump will be installed in the leak detection sump at least 135.4 feet in Cell 4A and N:\CeU4B\January 2011 Submittals and Revisions for CeI14B\O&M Plan 01. 1D.II\Cell 4A and 4B 0 M Plan Rev 2.1 -clean.doc Page 13 Ce1l4A BAT Monitoring, Operations and Maintenance Plan 1112010 Revision Denison 2.1 137.6 feet in Cell4B or more from the top of the flange invert. A pressure transducer installed within the pump continuously measures the solution head and is programmed to start and stop the pump within the ranges specified above. The attached Figure 5, illustrates the general configuration of the pump installation. A spare leak detection pump with pressure transducer, flow meter, and manufacturer recommended spare parts for the pump controller and water level data collector will be maintained in the Mill warehouse to ensure that the pump and controller on either cell can be replaced and operational within 24 hours of detection of a failure of the pumping system. The root cause of the equipment failure will be documented in a report to Mill management with recommendations for prevention of are-occurrence. Slimes Drain System (i) A pump, Tsurumi Model # KTZ23.7-62 stainless steel, or equal, will be placed inside of the slimes drain access riser pipe of each cell and a near as possible to the bottom of the slimes drain sump. The bottom of the slimes drain sump in Cell 4A and Cell 4B are 38 and 35.9 feet below a water level measuring point, respectively, at the centerline of the slimes drain access pipe, near the ground surface level. Each pump discharge will be equipped with a 2 inch flow meter, EIH Model #33, or equal, that reads the pump discharge in gallons per minute, and records total gallons pumped. The flow rate and total gallons will be recorded by the Inspector on the weekly inspection form. (ii) The slimes drain pumps will be on adjustable probes that allow the pumps to be set to start and stop on intervals determined by Mill management. (iii)The Cell 4A and Cell 4B slimes drain pumps will be checked weekly to observe that they are operating and that the level probes are set properly, which is noted on the Weekly Tailings Inspection Form. If at any time either pump is observed to be not working properly, it will be repaired or replaced within 15 days; (iv)Depth to wastewater in the Cell 4A and Cell 4B slimes drain access riser pipes shall be monitored and recorded weekly to determine maximum and minimum fluid head before and after a pumping cycle, respectively. All head measurements must be made from the same measuring point, to the nearest 0.01 foot. The results will be recorded as depth-in-pipe measurements on the Weekly Tailings Inspection Form; (v) On a monthly basis, each slimes drain pump will be turned off and the wastewater in the slimes drain access pipe will be allowed to stabilize for at least 90 hours. Once the water level has stabilized (based on no change in water level for three (3) successive readings taken no less than one (1) hour apart) the water level of the wastewater will be measured and recorded as a depth-in-pipe measurement on the Monthly Inspection Data form, by measuring the depth to water below the water level measuring N:\Ce1l4B\January 2011 Submittals and Revisions for Ce1l4B\O&M Plan 01.10.11\Ce1l4A and 4B 0 M Plan Rev 2.1 -clean.doc Page 14 Cell 4A BAT Monitoring, Operations and Maintenance Plan point on the slimes drain access pipe; 11120 I 0 Revision Denison 2.1 The slimes drain pumps for each cell will not be operated until Mill management has determined that no additional process solutions will be discharged to that cell, and the cell has been partially covered with the first phase of the reclamation cap. The long term effectiveness and performance of the slimes drain dewatering will be evaluated on the same basis as the currently operating slimes drain system for Cell 2. Tailings Emergencies Inspectors will notify the Radiation Safety Officer andlor Mill management immediately if, during their inspection, they discover that an abnormal condition exists or an event has occurred that could cause a tailings emergency. Until relieved by the Environmental or Radiation Technician or Radiation Safety Officer, inspectors will have the authority to direct resources during tailings emergencies. Any major catastrophic events or conditions pertaining to the tailings area should be reported immediately to the Mill Manager or the Radiation Safety Officer, one of whom will notify Corporate Management. If dam failure occurs, notify your supervisor and the Mill Manager immediately. The Mill Manager will then notify Corporate Management, MSHA (303-231-5465), and the State of Utah, Division of Dam Safety (801-538-7200). Cell 4A Solution Freeboard Calculation The maximum tailings cell pond wastewater levels in CellI, Cell 2, Cell 3, Ce1l4A, and Ce1l4B are regulated by condition 10.3 of the White Mesa Mill lle.(2) Materials License. Condition 10.3 states that "Freeboard limits, stormwater and wastewater management for the tailings cells shall be determined as follows: A. The freeboard limit for Cell 1 shall be set annually in accordance with the procedures set out in Section 3.0 to Appendix E of the previously approved NRC license application, including the January 10, 1990 Drainage Report. Discharge of any surface water or wastewater from Cell 1 is expressly prohibited. B. The freeboard limit for Cells 3, 4A and 4B shall be recalculated annually in accordance with the procedures established by the Executive Secretary. Said calculations for freeboard limits shall be submitted as part of the Annual Technical Evaluation Report (ATER), as described in Condition 12.3 below [of the licesnse and not included herein]. C. The discharge of any surface water, stormwater, or wastewater from Cells 3, 4A, and 4B shall only be through an Executive N:\Ce1l4B\January 2011 Submittals and Revisions for Ce1l4B\O&M Plan 01.10.ll\Ce1l4A and 4B 0 M Plan Rev 2.1 -clean. doc Page 15 Cell 4A BAT Monitoring, Operations and Maintenance Plan 1112010 Revision Denison 2.1 Secretary authorized spillway structure. [Applicable NRC Amendment:16] [Applicable UDRC Amendment: 3] [Applicable UDRC Amendment:4]" The freeboard limits set out in Section 6.3 of the DMT Plan are intended to capture the Local 6-hour Probable Maximum Precipitation (PMP) event, which was determined in the January 10, 1990 Drainage Report for the White Mesa site to be 10 inches. Based on the PMP storm event, the freeboard requirement for Cell 1 is a maximum operating water level of 5615.4 feet above mean sea level (amsl). The Cell 1 freeboard limit is not affected by operations or conditions in Cells 2, 3, 4A, or 4B. Cells 2 and 3 have no freeboard limit because those Cells are full or near full of tailings solids. Ce1l4A has no freeboard limit because it is assumed that all precipitation falling on Ce1l4A will overflow to Ce1l4B. All precipitation falling on Cell 2, 3, and 4A and the adjacent drainage areas must be contained in Ce1l4B. The flood volume from the PMP event over the Cell 2, 3, and Cell4A pond areas, plus the adjacent drainage areas, which must be contained in Ce1l4B, is 159.4 acre-feet of water. The flood volume from the PMP event over the Cell4A area is 36 acre-feet of water (40 acres, plus the adjacent drainage area of 3.25 acres, times the PMP of 10 inches). For the purposes of establishing the freeboard in Ce1l4B, it is assumed Ce1l4A has no freeboard limit and all of the flood volume from the PMP event will be contained in Ce1l4B. The flood volume from the PMP event over the Cell 4B area is 38.1 acre-feet of water (40 acres, plus the adjacent drainage area of 5.7 acres, times the PMP of 10 inches). This would result in a total flood volume of 197.5 acre-feet, including the 123.4 acre-feet of solution from Cells 2 and 3 and 36 acre-feet of solution from Cells 2, 3, and 4A that must be contained in Ce1l4B. The procedure for calculating the freeboard limit for Cell4B is set out in the DMT Plan. The Groundwater Quality Discharge Permit, No. UGW370004, for the White Mesa Mill requires that the minimum freeboard be no less than 3.0 feet for Cells 1, 4A, and 4B but based on License condition 10.3 and the procedure set out in the DMT Plan, the freeboard limits for Cells 1, 4A, and 4B will be at least three feet. Figure 7, Hydraulic Profile Schematic, shows the relationship between the Cells, and the relative elevations of the solution pools and the spillway elevations. The required freeboard for Cells 4A and 4B will be recalculated annually. N:\Ce1l4BVanuary 2011 Submittals and Revisions for Cell 4B\O&M Plan 01.1O.11\Ce1l4A and 4B 0 M Plan Rev 2.1 -clean. doc Page 16 Cell 4A BAT Monitoring, Operations and Maintenance Plan Attachments 11120 lO Revision Denison 2.1 1) Figures lA and IB, Initial Filling Plan, Geosyntec Consultants 2) Figure 2A and 2B, Initial Filling Plan, Details and Sections, Geosyntec Consultants 3) Figure 3A and 3B, Initial Filling Plan, Solution and Slurry Pipeline Routes, Geosyntec Consultants 4) Figure 4A and 4B, Interim Filling Plan, Geosyntec Consultants 5) Figure 5, Leak Detection System Sumps for Cell 4A and 4B, Geosyntec Consultants 6) Figure 6A and 6B, Leak Detection Sump Operating Elevations, Geosyntec Consultants 7) Figure 7, Hydraulic Profile Schematic 8) Ce1l4A and Ce1l4B Freeboard Calculations 9) Table 1 A, Calculated Action leakage Rates for Various Head Conditions, Ce1l4A, White Mesa Mill, Blanding, Utah, Geosyntec Consultants 10) Table 1B, Calculated Action leakage Rates for Various Head Conditions, Ce1l4B, White Mesa Mill, Blanding, Utah, Geosyntec Consultants 11) White Mesa Mill Tailings Management System and Discharge Minimization Technology (DMT) Monitoring Plan. N:\Ce1l4BVanuary 2011 Submittals and Revisions for Ce1l4B\O&M Plan 01.lO.11\CeIl4A and 4B 0 M Plan Rev 2.1 -c1ean.doc Page 17 ~ '\. ''\ -_ •. "GUD--EXISTING GROUND CONTOUR -MAJOR EXISTING GROUND CONTOUR -MINOR --5590--PROPOSED SURFACE CONTOUR -MAJOR PROPOSED SURFACE CONTOUR -MINOR ~ -- LIMIT OF LINER SPLASH PAD HOPE PIPELINE SLURRY OR SOUL TION SOLUTION RETURN SLIMES DRAIN "","-,---.~ "-, ~ :~ o 200' 400' ~-' ! GeosyntecD cOllsultants SCALE IN FEET INITIAL FILLING PLAN CELL4A BLANDING, UTAH DATE: OCTOBER 2010 PROJECT NO. SC0349 T FIGURE 1A ,.,.____ LTSOf~£R ,. --- I I - I ' -r==-' , ( "'--"":::- I I I I -, I I '" ~ I I ' -~, I I ' " --=-::.. I i J I r;...,-:::- I ' :,' ,', -=. I 1,'1 " I.' I ' I 1 J I I -;;;;-;:. I 1 1 1 1 ;;;;-;:.. I ' " ' - I ," I I I I I I I I I I I I I I I \ '\ ... _---- ---~-.--- ' .... _------- ------------ ------------ --------... -.-------------------------::~::::---------------- SCUlTION RETURN T LEGEND EXISTING GROUND CONTOUR EXISTING GROUND CONTOUR MAJOR MINOR --5590--PROPOSED SURFACE CONTOUR -MAJOR ---PROPOSED SURFACE CONTOUR -MINOR - - - - - -UMIT OF UNER = SPLASH PAD HOPE PIPEUNE SlURRY OR SOUL TION SOLUTION RETURN ----- -- --SliMES DRAIN o 200' 400' ~' I SCALE IN FEET INITIAL FILLING PLAN CELL4B BLANDING, UTAH GeosyntecDI DATE: OCTOBER2010 I FIGURE 18 consultants PROJECT NO SC0349 RETURN 8" HOPE PIPELINE SOLUTlOi~ SLURRY OR SOLUTION r I I I I I r ./ L.... ,.. . ==---r-- A .................... ~. ~ -.L.... .................... ~ ! j , 00 "IL HOPE GEO"EM""~NE (5"001>1) aoOS'INl1£l1C CLAY LlNEll -:::--.. -:--.......................... ---=---. .................... I / I I I I WAIDlLINE I./" T;~ ~:·~OPE1 LEGEND EXISTING GROUND CONTOUR -MAJOR EXISTING GROUND CONTOUR -MINOR --5590--PROPOSED SURFACE CONTOUR -MAJOR PROPOSED SURfACE CONTOUR -MINOR - - - - - -UMIT Of UNER ~ SPLASH PAD -• -HDPE PIPELINE SlURRY OR SOULTlON SOLUTION RETURN SUMES DRAIN VALVE ==--. JLlMITS OF UNER _ ------;;;;-;:;. --;;;;--,. -.......... I I / I I I I----\ _~85--~ o 100' 200' to;;;-. I SCALE IN FEET INITIAL FILLING PLAN, DETAILS AND SECTIONS CELL4A BLANDING, UTAH T A SECTION .J \.:::7 ~~ PAD I GeosyntecC>1 DATE: OCTOBER 2010 C()ItSUlla.llts I PROJECT NO SC0349 FIGURE 2A , , I , ( , , , I I I I I A. SECllON \9 SPLASH PAD SCAl.[; N.T.S. LEGEND EXISTING GROUND CONTOUR EXISTING GROUND CONTOUR MAJOR MINOR --5590--PROPOSED SURFACE CONTOUR -MAJOR PROPOSED SURFACE CONTOUR -MINOR -- - - - -UMIT OF UNER r 7 Z 7 Z?? ? 21 SPLASH PAD • ~ HDPE PIPEUNE SLURRY OR SOUL TION ... SDlU110N RETURN ---------SUMES DRAIN T o 100' 200' \;;;;-' I SCALE IN FEET INITIAL FILLING PLAN, DETAILS AND SECTIONS CELL4B BLANDING, UTAH GeosyntecC> DP.1E: OCTOBER 2010 consultants PROJECT NO_ SC0349 AGURE 2B SOLun ON RETURN ~---~----------------------..... ~ / ,\ I ~\. I '\0 ~~~~l:~N I j I' ( I \ \ BARGE I , f" --~ , \ \-.......... \ , \ , \ \ \ , LEGEND EXISTING GROUND CONTOUR -MAJOR EXISTING GROUND CONTOUR -MINOR --5590--PROPOSED SURFACE CONTOUR -MAJOR PROPOSED SURF'ACE CONTOUR -MINOR - - -LIMIT OF UNER ~ SPLASH PAD --'-HOPE PIPELINE SLURRY OR SOULTION • SOLUTION RETURN SLIMES DRAIN , t:---,I 8" HOPE PIPELINE SLURRY OR SOLUTION \' '\ ~ \, '\ \\ \~ \' 1\ ~ o 100' 200' --- SCALE IN FEET INITIAL FILLING PLAN, SOLUTION AND SLURRY PIPELINE ROUTES CELL4A BLANDING, UTAH FIGURE PROJECT NO SC0349 3A GeosyntecC>1 DATE; OCTOBER 2010 I cllr$ullarll~ SOlUTION RElVRtI 6" OR B" HDPE PIPEUNE \ II SLURRY OR SOLUTION """"-,I \1 , \1 I \~ LEGEND ~S~NG GROUND CONTOUR -MAJOR EXIS~NG GROUND CONTOUR -MINOR --5SS0--PROPOSED SURFACE CONTOUR -MAJOR ----PROPOSED SURFACE CONTOUR -MINOR - - - - - -UMIT OF UNER rlZZI 2 2 2 2. SPLASH PAD • ~ HOPE PIPEUNE SLURRY OR SOUL ~ON ~ SOLU~ON RETURN ---------SUMES DRAIN , \ I I \ , ... .... , V UMITS Of UNER , I I I , • , • , • • ~~ o 100' 200' ~ I SCALE I N FEET INITIAL FILLING PLAN, SOLUTION AND SLURRY PIPELINE ROUTES CELL4B Geosyntec t> consultants BLANDING, UTAH DATE: OCTOBER 2010 PROJECT NO SC0349 AGURE 38 • I 'I ( , ____ --:1: a . " 0 z is '" 0 c .:g 0 z 5 a:: " " z ~ III X '" .... 0: '" 0 < 0 z ::< ~ I I '" oc ::::J ::::J 0 g r-z z 0 0 fJ U W fJ « LL Q: '" :::J III w Z 0 0 ::J « "-w III "- 0 0 I III <L .... 0 « '" ~ ..J "-"-III I 0 rn '" on I ~-~--,. --;' -- I I UIIIlS Of' UtI9l I , • OPE PIPELONE 6" OR B oi: SOLUTION SLURRY , , -r::;-;:;";"~-'~~-"::::-::..r " "'-:---"1. -------..~~;... ' , I I ' ,,' "" , , , ' , , " , ' , , , " , , " , , . ,', :', --- .. _---------------............. _._----._-------------------... -I I I I \ ---------------------------------------------- '\ , .... -----------.... _----- ------------- -------------- RETURN 1 LEGEND EXISllNG GROUND CONTOUR MAJOR EXISllNG GROUND CONTOUR -MINOR --5590--PROPOSED SURFACE CONTOUR -MAJOR PROPOSED SURFACE CONTOUR -MINOR = UMIT OF UNER SPLASH PAD "-HOPE PIPEUNE SLURRY OR SOUL 1l0N SOlU1lON REllJRN SUMES DRAIN o 200' 400' ~-' I SCALE IN FEET INTERIM FILLING PLAN CELL4B BLANDING, UTAH FIGURE 4B GeosyntecP DATE: OCTOBER 2010 consultants PROJECT NO" SC0349 22.5" ELBOW 18" '/J SCHEDULE 40 PVC SECTION [EAK~ DETECTIOI'fSYSTEM-SD MP N.T.S. LEAK DETECTION SYS1EM 4" \!l SCHEDULE 40 PVC 4" ¢ SCHEDULE 40 PVC GEOSYNTHEll C CLAY LINER 60 MIL HOPE GEOMEMBRANE (SMOOTH) CUSHION GEOTEXTILE LEAK DETECTION SYSTEM SUMP CELLS 4A AND 4B BLANDING, UTAH ~ Geosyntec t;. .. I consultants I PROJECT NO SC034 9 I DATE: OCTOBER 2010 IGURE 5 PUMP bN LEVEL 5655.69 FEET MlSI LEAK DETECllON SUMP ELEVATION: 5553.64 FEET.AMSI MAXIMUM SOWnON EU:VATlON: 5556.14 FEET AMSI LOWEST SOLlITlON ELEVATlON: 5555.14 FEET AMS( LEAK DETEC110N SUMP CELL4A BLANDING. UTAH Geosyntec D I DIllE! OCTOBE.R.2Il-10 Cllll~\II:ums I PROJeCT NO. SC0349 FlGuRE 6A ;1;' MAXIMUM S.OLUTION ELEVATION: 5558.5 FEEt AMSI ____ c __ • __ • __ • __ PUMP ON LEVEL 5557.69 FEET AMSI - -. --• -- LEAl< DETECTION SUMP EI.,I;VATION: 5555.44 PEET AMSI LOWEST SOlUTION aevATlON: 5557.5 FEET AMSI LEAK DETEcnON SUMP CELL 48 BlANDING. UTAH J I GeosyntecC>\ DATE! 0cr08ER2010 I fiGURE. (lfJQSuJtan1s AAOJECTNO. SC0349 68 PMP VOLUME 38.1 AC-FT. PLUS 159.40 AC-Ff FROM CELL~ -I 'I • 2,3,AND4A TOTAL 197.S0 AC-FT CELL4B FREEBOARD LIMIT 5594.64 FT. MSL PMP VOLUME, 36 AC-Ff. PLUS 123.4 AC-Ff FROM CELL 2 AND CELL 3 159.40 AC-FT OVERFLOWS TO CELL4B PMP VOLUME, 123.4 AC-FT OVERFLOWS TO CELL 4A NOT TO SCALE HYDRAULIC PROFILE SCHEMATIC CELL 4B BLANDING. UTAH ~r.0349 ~ Geosyntec t> .. I consultants I PROJECT NO. DATE: OCTOBER2010 AGURE 7 Geosyntec Consultants Table 1A Calculated Action Leakage Rates for Various Head Conditions CeIl4A, White Mesa Mill BTanding, Utah Head Above Liner CaJculated Action Leakage Rate System (feet) (gallons/acre/day) S 222.04 10 314.0 15 384.58 20 444.08 25 496.5 30 543.88 35 587.5 37 604.0 Geosyntec Consultants Table lB Calculated Action leakage Rates for Various Head Conditions Cell 4B, White Mesa Mill Blanding. Utah Head Above Liner System Calculated Action Leakage Rate (feet) (ganons/acre/dav) 5 211.4 10 317.0 15 369.9 20 422.7 25 475.6 30 528.4 35 570.0 37 581.2