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HomeMy WebLinkAboutDRC-2012-003701 - 0901a068809be151ogR0-ecL2-0trI087 DEN,ronDll MINES January 27,2012 VIA PDF AND FEDERAL EXPRESS Mr. Rusty Lundberg Executive Secretary Utah Division of Radiation Control Utah Department of Environmental Quality 195 North 1950 West Salt Lake City, UT 84116-3097 i", ' dl at r.'.":,).'.=.'\-',"vt.J. /LJ Re: Response to DRG Letter on Failure to Meet Affirmative Defense Requirements Cell2 Slimes Drain Recovery Elevation Utah Ground Water Discharge Permit UGW370004 This letter responds to Utah Division of Radiation Control's ("DRC's") December 20,2011 letter regarding Denison Mines (USA) Corp.'s ("Denison's") White Mesa Mill's (the "Mill's') compliance with the Discharge Minimization Technology ('DMT') provisions in Utah Groundwater Discharge Permit UGW370004 (the "GWDP' or the "Permit") regarding Tailings Cell 2 Slimes Drain recovery elevation. Reference is also made to: o the DMT Report for the fourth quarter of 2011 submitted by Denison on February 25,2011, which identified that the monthly slimes drain monitoring requirement seriously interferes with the pumping needed to reduce the slimes drain level,. a conference call with DRC on May 25,2011,. the Notice pursuant to Part 1.G.3 of the GWDP, submitted by Denison on May 27,2011,o the Plan and Schedule submitted by Denison on June 17,2011 which identified the actions which Denison considered would be sufficient to return the slimes drain system to compliance with the GWDP, ando the Status Update Report submitted by Denison on August 1,2011, which confirmed that the actions proposed in the June 17,2011 Plan and Schedule to be performed by Denison had been completed. DRC's December 20,2011 letter identifies a number of requirements, based on the assumption that the actions completed in 2011 were not sufficient to reduce the Cell 2 slimes drain level and that the actions identified in the letter and its accompanying Stipulated Consent Agreement would be necessary to bring the Cell 2 slimes drain recovery system into compliance with the provisions of the GWDP. However, as discussed with you on January 19,2012, because the Cell 2 slimes drain system is now in compliance with the DMT provisions of the GWDP as a result of the actions completed during 2011, it is our understanding that the requirements set out in DRC's December 20, 2011 letter are no longer required. lncluded with this letter is information demonstrating that the Cell 2 slimes drain has achieved compliance with Part 1.D.3 of the Permit for 2011. Part 1.D.3(bX3) of the Permit requires that annual slimes drain C:\Users\DFRYDENLUND\AppData\Local\Microsoft\Windows\Temporary lnternet Files\Content.Outlook\M5MKKEM0\01 27 12ltr to R Lundberg slimes drain Cell2 compliance.docx rt{. iil, ^r I t'l r,f.,.: - '-.lt\" tr)\ ;:- t, ""fi \ r:;) tl.J 1..) "..;, Denison Mines (USA) Corp. 1050 17th Strset, Suite 950 Denver, CO 80265 USA r fel : 303 628-7798i Fax: 303 3894{25 www.denisonmines.com o ndbergLetter to Mr. Rusty Lu January 27,2012 Page 2 compliance shall be achieved when the average annualwastewater recovery elevation in the slimes drain access pipe, as determined in the currently approved DMT Plan, meets the conditions in the formula (the "Formula") spelled out in Part 1.D.3(bX3) of the Permit. Attachment 1 contains the Cell 2 Head Measurement Test data forms for the months of January through June 2011, when the measurement requirement was monthly, and for the third and fourth quarters of 2011, after the GWDP was changed to require quarterly measurements. Attachment 2 contains the Cell 2 slimes drain elevation plot for 2009, 2010, and 2011. Attachment 3 contains a spreadsheet with calculations demonstrating compliance with the formula in Part 1.D.3(b)(3) of the Permit for 2011. It should be noted that as a result of the additional volume of cut and fill added to the Cell 2 interim cover during the re-grading completed in July 2011 to minimize the accumulation of storm water, the slimes drain access pipe was extended 6.97 feet to maintain the monitoring point above the interim cover. This extension is reflected in the entry for the "Elevation of the Measuring Point" and the "Depth to Liquid" in Attachment 2 for the fourth quarter of 2011 (December 19, 2011). The axis for "Feet Below Top of Standpipe" (the y-axis) in the Cell 2 slimes drain elevation time plot in Attachment 2, has also been adjusted to be consistent with the new elevation of the Measurement Point at the top of the standpipe. ln addition, the standpipe elevation was re-surveyed in 2011, which indicated that the elevation of the measuring point of 5614.83 feet above mean sea level (fmsl) reported to date (prior to the 6.97 foot extension) was 3.07 feet higher than the 2011 survey result of 5611.76 fmsl (prior to the 6.97 foot extension). The y-axis has also been corrected to reflect this 2011 survey data. These corrections of axis have no effect on the resulting slimes drain elevation values listed in and used in the calculation in Attachment 3, or plotted in Attachment 2, since those values are generated from the difference between the elevation of the measurement point and the depth from the measurement point to the solution level, both of which have increased by the same value of 6.97 feet and both of which reflect the correct survey results. Since the Cell2 slimes drain system is now in compliance with Part 1.D.3(b)(3) of the Permit, based on the actions proposed and installed by Denison during 2011, we understand thatfuture compliance will be determined using the provisions of the GWDP and that a Stipulated Consent Agreement is not required. Further, based on the 2011 results, which indicate achievement of compliance through the actions proposed and completed by Denison to date, Denison believes that those measures will be sutficient to maintain compliance in the future and that it is not necessary at this time to consider any of the further actions discussed with DRC. As a final point in response to your December 20,2011 letter, there appears to be a misunderstanding or confusion regarding what commitments were made by Denison to DRC in the communications during 2011. During the May 25,2011 telephone call, DRC and Denison discussed the factors that Denison believes led to the non-compliance situation, specifically: o that the frequency of monitoring (monthly) interfered with the pumping time needed to reduce the slimes drain level, and. that the formula used for determining compliance may be flawed. DRC and Denison also discussed a number of potential actions including reduction of the monitoring frequency, re-grading of the interim cover, an engineering evaluation of the current pump, installation of one or more piezometers, and other potential engineering changes, which DRC identified as optional actions for Denison's evaluation. DRC requested that Denison evaluate these options and submit a formal notice under Part 1.G.3 of the Permit on or before May 27,2011. Based on these discussions, Denison submitted the Notice on May 27,2011 identifying the following proposed actions: DENISOJ)// ,YTINES o ndbergLetter to Mr. Rusty Lu January 27,2012 Page 3 . re-grading the interim fill on Cell 2 in order to reduce the potential for the accumulation of stormwater on the surface of Cell 2, which can potentially infiltrate into Cell 2;o installing one or more piezometers into Cell 2 for the purposes of monitoring the water level inCell2 in lieu of continued monitoring of the Cell 2 slimes drain access pipe, and to submit a plan and schedule to the Executive Secretary on or before June 17, 2011 with respectthereto. The Plan and Schedule was to be subject to Executive Secretary approval, and piezometer installation was to occur after Executive Secretary approval;. performing an engineering evaluation of the current pump in the Cell 2 access pipe to determine if any changes can be made to improve its efficiency and output; ando amending the Permit to adjust Part 1.D.3(b)(2) to reflect the changes in the monitoring of the Celt2 water level, resulting from the installation of the piezometer(s) and approved monitoringprocedure set out in the amended DMT Plan, and to reduce the frequency of monitoring from monthly to quarterly. Shortly thereafter, when preparing the plan and schedule, Denison completed an engineering evaluation which determined that the installation of piezometers would not be feasible or effective. The engineering issues precluding the use of piezometers were discussed in Denison's June 17, 2011 Plan and Schedule-. Shortly thereafter, on June 30, 2011, DRC issued a draft revision of the GWDP for Denison's review,which reduced the frequency of monitoring the Cell 2 slimes drain from monthly to quarterly, but which did not contemplate any changes in the monitoring of the Cell 2 slimes drain water level resulting from the installation of any piezometers. DRC published the amended Statement of Basis and GWDP, containing no requirements for additional piezometers, on July 14,2011. Based on the foregoing, Denison's understanding is that DRC did not require the installation ofpiezometers, nor did Denison commit to installing additional piezometers during the May 25, 2011 call. Denison proposed to add one or more piezometers in its May 27, 2011 Notice, to be detailed in a plan and Schedule to be submitted by June 17,2011. ln preparing that Plan and Schedule, Denison concluded that the installation of additional piezometers would not be feasible and effective, and explained the reasons for that conclusion in its June 17, 2011 submittal and in so doing revised its proposal to exclude the installation of any additional piezometers. The June 17,2011 Plan and Schedule was subject to Executive Secretary approval. On June 30 DRC issued a draft revision to the GWDp thatwas consistent with continued monitoring at a reduced frequency in the existing slimes drain and whichdid not address the installation of piezometers to be used for monitoring in lieu of the existing slimesdrain. On August 1,2011, Denison provided DRC with a letter confirming that Denison had completedthe items set out in the June 17, 2011 Plan and Schedule, and restating that no piezometers wereproposed to be installed. Denison was not aware that DRC disagreed with Denison's revised proposal until receipt of your December 20,2011 letter. ln any event, given that the Mill is now in compliance with Part 1.D.3(b)(3) of the Permit, it would appear that no further actions are required at this time. Please contact me if our understanding is incorrect or if you have any questions or require any further information. v, DEN'SOJ)// ,UINES o LundbergLetter to Mr. Rusty January 27,2012 Page 4 cc: Ron F. Hochstein Harold R. Roberts Jo Ann Tischler David E. Turk Kathy A. Weinel 4 oEN'soNt)// o ndbergLetter to Mr. Rusty Lu January 27,2012 Page 5 ATTACHMENT 1 DENISOJ)// ,YIINES MONTHLY HEAD MEASUREMENT TEST January-11 Date:u2112077Location: Slimes Cell# 2 Sampler: thTl2ott tlL8.lz9tL L/79l2OtL Garrin Palmer, Ryan Schierman Tanner Holliday Ll20l20L1 Ll21/aOLL 600 700 800 900 1000 1100 1200 1300 1400 1s00 1500 16.15 15.10 t4.73 L3.74 13.15 16.09 15.08 73.73 13.1514.L3 16.03 15.06 L4.t2 13.73 13.15 15.98 15.04 14.05 13.72 L5.92 15.00 14.03 13.59 15.86 t5.73 L4.84 14.00 13.95 L3.92 13.90 14.9s 14.89 L3.67 13.5415.79 15.59 14.80 13.59 13.55 All measurements are in inches. Comments: Report number is 13.15 for the month of January. The tested started with a partialy recovered head because there was an unplanned power loss to the tailings area over the weekend which allowed the head to recover for a day and a half to two days before the monthly head recovery test was started. they continue to have some problems with the power supply out on the tailings area. We may continue to see some problems with the slimes drain on Cell 2 until these issues are resolved. MONTHTY HEAD MEASUREMENT TEST Location:Date: Sampler: 2/2312O1L 2128l20tt Slimes Cell# 2 Tanner Holliday Garrin Palmer 2l2u20lt 2122/20Lt 2/2412O1L 2l2s/2O7L 2/28/2017 600 700 800 900 1000 1100 1200 1300 1400 1500 1600 1o.42 L4.7 - 14.59 12.73 to.42 LO.4212.7 11.8 LL.82 14.47 L4.35 12.63 Lt.79 1!.2 12.6 12.s6 77.77 11.18 t4.22 L7.73 11.18 t4.L L2.5 11.59 11.15 13.96 L2.M 11.65 11,11 13.87 L2.38 11.63 11.03 24.85 13.77 t2.32 tt.6 10.99 All Measurements are in inches. Comments: Test got started late on th 21st and ran over the weekend. The stable readings were taken the follswing Monday morning on the 28th. The number being used as stable head for the report is 10.42 feet. MONTHLY HEAD MEASUREMENT TEST Location: Slimes Cell# 2 Date: Sampler: 3176/20L73lL4l2O7t 3l7s/20L7 3/t&laOLL Tanner Holliday Garrin Palmer 3lfil20fl 3ltglzgl1- 600 700 800 900 1000 1100 1200 1300 1400 1500 1500 24.75 14.31 12.56 t4.45 12.67 Lt.76 Lt.73 L7.71 11.69 11.55 LL.64 17.62 LL.32 11.31 23.25 74.L9 12.53 11.31 22.31 21.2L L4.O5 73.92 12.50 12.46 12.42 11.31 20.68 13.82 19.78 79.25 78.76 13.72 L2.36 13.61 13.53 12.30 11.60 12.22 Ll.52 AII measurements are in inches. Comments:The report number for the month of March is 11.31 MONTHTY HEAD ME ENT TEST Location: Slirnes Cell# 2 Date:412slz0Lt Sampler: Tanner Holliday 4l22l2}tt 4l23l20tL 4/241207L 4l2sl2o11 lL,57 tL.57 11.57 11.55 4l20lzott 600 700 8@ 900 1000 1r00 1200 1300 1400 1500 1600 24.48 15.40 13.69 L2.94 ----- 23.02 15.26 13.68 12.91 ----- 22,23 1s.12 13.68 12.88re----2t.52 15.03 L3.67 12.85 20.80 14.95 13.61 72.82 20.37 t4.82 13.50 L2.81re 19,73 14.77 13.40 12.78 19.40 14.53 13.35 12.75 19.01 L4.6L 13.29 12.72 Comments: The report number for the month of April is 11.57 The Head test was started on a Tuesday due to some minor power lssues that needed to be adressed on Monday the 18th. MONTHTY HEAD MEASUREMENT TEST Location: - Slimes Cell fi 2 Date: slzc,lz0ll Sampler: Tanner Holliday 600 7N 8m 900 1000 1100 1200 1300 1400 1500 1600 Garrin Palmer slt'l?ott sltilIotL 5178120L7 'ltglzott 'lzolzaLt ---- ----- 15.55 I'1.61 13.69 13.20 -- 14.ss 13.65 13.1923.4sE---- 22.85 14.48 13.53 13.18 21.91 16.20 14.41 13.61 13.L7 ----- 21.53 16.07 14.36 13.58 L3.17 21,10 15.95 t4.12 13.55 13.17 -u--- 20.52 X5.85 74.21 13.54 Il|E----20.09 75.76 14.22 13.52 --m-- 19.75 15.64 14.L6 13.50 24,89 16.44 -16.30 Comments: the report number ls 13,17 for the month of May. MONTHTY HEAD MEASUREMENT TEST Locatlon:Date: 6123/20LL Sllmes Cell# 2 Sampler: tannerHolliday Ryan Shierman 6l73l20tL 6h4l2ott, 6ltsl20L7 6l16l20lt 6l7l2ott 6l18l20tL 6l2ol21t1m--G--- 500 ------- 700 24'90 t7.t6 15.28 t4,14 13.s5 13.04 t2.t8 ---G--E 800 23.90 17.05 75.24 14.10 13,49 12.18 900 21.26 16.9s 15.20 14.0s 13.47 L2.t8 -G----- 1000 22.49 16,84 Ls.77 14.02 13.46 -EG---m 1100 21.9s t6.7L 15.11 13.99 13.46 ------- 1200 21.53 16.63 15.03 13.95 13.45 ------E 1:100 2L.01 16.55 14.9s 13.91 13.43 ------- 1400 20.51 16.40 L4,87 13.85 13.40 -----E- 1s00 19.97 15.31 L4.79 13.79 13.32 ------- '1500 ----re- 12.18 ------- Comments The report number ls 12.18 for the month of June 2011. MONTHLY HEAD MEASUREMENT TEST Location: Slimes Cell# 2 Date: Sampler: 15.81 - 15.75 7lzolzolt Ryan Sheirman Ryan Palmer 7l,JlzAfl 7lt2l2o17 7l13l201-t 7lt4lzolL il75120t7 600 700 800 900 1000 1100 L200 1300 1400 1500 1600 - 23.81 - 23.24 - 22.9t - 22.t 2L.9 - 27.49 L4.89 - 14.85 14,82 - t4.12 - 14.09 7he/20t1 - - 12.59 - 12.59 12.s9 t7.43 16.90 - 16.U 15.73 17.21 15.70 - 15.64 L7.O6 1s.615-21.15 16.95 15.55 - 15.49 15,43 - t4.o7 74.78 14.05 74.73 t4.77 14.00 -14,66 14.63 - 14.59 73.97 - 13.95 - Comments:Addatlonal were taken on Saturday the 15th and Sunday the 17th. Saturday at 1800 hrs the leve! was :!3.:!l_1teg1 lq9unday at lzqq hours the levelwas 12.70 number will be 12.59 which was taken on the 19th. The slimes draln ptpe and the LDS pipe on Cell 2 will have to be raised up to maintain a reasonable amount of exposed plpe above ground elevation. The dlrt work ls moving forward and oioes will be extended with in the next week to ten days. QUARTERLY H D MEASUREMENT I TEST o EA Location: Slimes Cell # 2 Date: Sampler: l2lt9t20tt Garrin Palmer Tanner Holliday tzn2nt tzlt3nt 35.55 26.24 t2n4nt t2nsnt 23.90 22.7 t2n6nt 2t.94 rznTnt t2n8nt 12n9nt 600 700 800 900 1000 I 100 1200 1300 1400 1500 1600 34.63 33.69 26.09 25.85 32.78 25.61 23.81 22.63 22.57 23.72 22.55 21.94 21.93 2r.88 19.83 20.31 32.13 31.89 25.67 25.43 23.63 22.51 23.59 22.48 21.84 22.4731.22 25.29 22.44 21.8 21.7730.74 29.99 25.12 24.95 23.52 23.48 22.42 21.76 Comments: Two readings were missed on l2ll4 because of monthly GW sampling event. Readings were taken Saturday the lTth and Sunday the 18th. The final number will be 19.83 The slimes drain was extended on Cell 2 when the cell's final cover was placed. The slimes two head measurement is now 45' which is up from 38'previously. o LundbergLetter to Mr. Rusty January 27,2012 Page 6 ATTACHMENT 2 6 DEN'SOJ)// IUIINES TnzllelTr rnzlulor TTOZIOEI6 TTOZITEl8 filzlrclL fiozlle/s filzlrcls rrozl0eln rrozlEle ttozlszlz rwzlfflr otlzltElzt orozl0Eltr otlzlrEl0r or0zl0E/6 owzlfils otozltElL orozl0E/s orozlTEls onzl0el? orozlrElE orozlszlz OTOZITEIT 600zlrElzr 600zloE/1r 600zltEl0r 600zllel6 600zlIL€l8 600zlrelL 600zllels 6002/E/s 600zlleln 600zlt€.le 600zl8zlz 600zl,e/r N o'tro.h (EoL = I F{ F{oNdoF{oN orooN I .= lUSo lno .E -lrl N -o(J (\ .g oItt + oooqqq60NFINN edldpuels 1o dol flrotag laal Letter to Mr. Rusty January 27,2012 Page 7 o Lundberg ATTACHMENT 3 DEMsoJ)l/ TUIINEg N) \o N) { \ot) o N.J [.J Ur N tl + N N 6 NJ N) NJa NJ N) N) t'J Y3(!o q 0q UIo @\()) (Jro\ .J UIo\ i UIo\ \ UTo\ \ Ur01 \ (Jlo\ \ Uro\ .J t! p -O ^z ,E Ft(! 6 (, (/J Or Io iri +6I@ N)(^t.,!^,iJl L,J s |, N)o\\t \o !.,\o{ Ur(,\o oo UlUl\op UI L'T\o\o Ul UlUl\ooo UI Uro\(Jlo\ s Uro\ U)N L'IUI\o@ b. 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(\ G. i\)q G'at\ s t\)S 6 \ S oG \i G o V) s a bJ-* PB,oo o o0 0 eI t) N oG ha\) v) R'S.e(st, U s o \JSl\lr.(\ S- 5e\, S oGG UG SS eu, si, S o IlRc-zo1l-oen g MINES /S ?l rer:303628'77e8 l|R k'i Fax:30338e4125 \*). ;!l www.denisonmines.com\+. t"/ \{ , e",/ August l.20ll VIA PDF AND FEDERAL EXPRESS Mr. Rusty Lundberg Executive Secretary Utah Division of Radiation Control Utah Department of Environmental Quality 195 North 1950 West Salt Lake city, UT 84116-3097 Re: White Mesa Mill Cell2 Slimes Drain Compliance - Confirmation of Completed Steps from June 17,20ll Plan Letter This letter provides confirmation of the actions committed to during discussions in Denison Mines (USA) Corp.'s ("Denison's") conference call with Utah Division of Radiation Control ("DRC") on May 25,2011 and in a in June 17,2011 Status Update letter regarding Cell 2 Annual Slimes Drain Compliance (the "June Status Update" or the "Status Update Letter") at White Mesa Mill. The actions are addressed in this letter in the same order as they were discussed in the Status Update Letter. Re-grading of Interim Fill on Cell2 The Status Update Letter committed that Denison would re-grade the interim fill on Cell2 on or before August 1,2011 in order to reduce the potential for the accumulation of stormwater on the surface of Cell 2, which can potentially infiltrate into Cell2. Denison believes that the reduction of infiltration by removal of low areas and filling of potential pooling spots will have a positive effect on the slimes drain level. Denison completed f,rlling and regrading of Cell 2 on July 30, 2011. The regrade required 62,000 cubic yards of cut and fill, consisting of alluvial material and/or rock. Drawings of the cell regrading plan are provided in Attachment 1. Photographs of the completed regrading are provided in Attachment 2. N:\Cell 2\08.01.11 ltr to R lundberg Cell 2 completion\O8.01.11 ltr to R Lundberg Cell 2 modifications.docx Letter to Mr. Rusty Lrrd;g August l,20ll Page 2 Installation of Piezometers As discussed in the Status Update Letter Denison has performed an engineering evaluation of issues related to the feasibility of installation and use of piezometers in Cell 2 for the above purpose. Based upon this further evaluation, Denison does not believe that it is feasible to install and operate peizometers that would provide representative and dependable measure of the slimes drain level for the following reasons. For the reasons stated in the letter, including l. The likelihood that artesian effects will create piezometer levels inconsistent with slimes drain levels; 2. The fact that no piezometer or collection of piezometers could represent cell-wide conditions; and 3. The high risk of continual plugging Denison has determined that piezometer installation is not feasible in Cell 2 and, as stated in the Status Update Letter, has not installed piezometers. Engineering Evaluation of Pump in Cell2 Denison performed an engineering evaluation of the current pump in the Cell2 access pipe to determine if any changes can be made to improve its efficiency and output and has made mechanical changes to the pump configuration and adjustments to the pump operational cycle as discussed below. As discussed in the June Status Letter, the sensor settings (which trigger pump startup) were adjusted from the former 0 feet to 4 feet setting to the current setting of 0 feet to 2 feet. As a result, the pump rate has been slowed sufficiently to allow the pump to cycle on more frequently for a longer time at a narrower range of solution levels, in effect, performing like a smaller pump, as suggested by DRC. This mode of operation has been maintaining as lower slimes drain level based on the increased frequency of pumping. Amendment of the Groundwater Discharge Permit for Reduced Monitoring Frequency Denison has received DRC's June 30, 2011 Draft Statement of Basis Memorandum and Draft amended Groundwater Discharge permit. As agreed upon in a telephone conversation between Denison and DRC during the week of July 25, 2011, Denison will provide comments or proposed markups to the draft documents by August 17 ,2011. Please contact me if you have any questions or require any further information. DENISOJY/MINES Letter to Mr. Rusty Lrrt, August l,20ll Page 3 Yours very truly, Drxrsox Mnrns (USA) Conp. Jo Ann Tischler Director, Compliance and Permitting cc: David C. Frydenlund Ron F. Hochstein Harold R. Roberts David E. Turk Kathy A. 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N BcJ rele sElln R6 E X d -ldi oi ci Ail$i + E=5"1 g lg Hs lfi H !- I oolo ;Hq 3313 ;ed IEl$ SEiln $.E = <l O) lo) N C\ llfl lfl,sEl H lH E' lil H = I '+ -l< o .o .olo =gd 3:13 [:31[ E=IIIE s= I sxls PEslE H Ed - dl; oi ci cjlc,iiol I I I o-l- -o.l-q €l i [l= i s:l;Ed 8:lE E$EIHI R lR P' IE i@lN; 9roN6i at,ool -dEO ON 8EeEXolu H'o-;1 I "i9d,sl:6$-9:< LoCLxtrl Eo<L E t.llg B IN Go ICD .Et(!ooE*l oo =:oiIEEooLL!la ii 'ii!16(d t\\-r ;B(\ttl 5NN6)6(u2EE C"I^I F:l4H -clroEElE.?E 99=tses:e ,aS:#:iE#li rr9:i866ooo L c(gt (L Ior,rE aeqEo-qi:dL OE6*l E edHEt E,gE*:; b =p,r.S oE.>f- !DEEBE < (5 Letter to Mr. Rusty L*dtg August l,20ll Page 5 ATTACHMENT 2 DENISOJY/ ,YIINES $S.,r, ,u - ', e!...e,r..... n'r&s Cell 2 - Looking Northeast Cell 2 - Looking Southeast #1 Cell 2 - Looking East #2 Cell 2 - Looking East #1 Denison Mines (USA) Corp. 1050 17th Stre€t Sulte 950 Denver, GO 80265 USA Tel : 303 628-7798 Fax : 303 389.4125 www.denisonmines,com June 17,2011 VIA PDF AND FEDERAL EXPRESS Mr. Rusty Lundberg Executive Secretary Utah Division of Radiation Control Utah Department of Environmental Quality 195 North 1950 West Salt Lake city, uT 84116-3097 Re: White Mesa Mill Cell2 Slimes Drain Compliance -Status Update and Plan and Schedule This letter provides an update on the status of actions committed to in Denison Mines (USA) Corp.'s ("Denison's") May 27,2011 Notice regarding Cell 2 Annual Slimes Drain Compliance (the "May 27, 20ll Notice" or the 'Notice") at White Mesa Mill and discussions during our conference call with Utah Division of Radiation Control ("DRC") on May 25,2011. Re-grading of Interim Fill on Cell 2 The Notice committed that Denison would re-grade the interim fill on Cell2on or before August 1,2011 in order to reduce the potential for the accumulation of stormwater on the surface of Cell 2, which can potentially infiltrate into Cell2. Denison has completed an updated survey of the Cell2 surface which has identified low areas that could be regraded. Denison has prepared a plan for regrading the surface. The completed plan will require 50,000 cubic yards of cut and fill, consisting of alluvial material and/or rock, to level out low areas on the current surface. Denison believes that the removal of low areas and filling of potential pooling spots will have a positive effect on the slimes drain level, by reducing inf,rltration. As proposed in the Notice, Denison expects to compete the proposed regrading by August 1, 20il. NlCell 2\06.17.11 Plan and sched slimes drain dewateA06.17.11 ltr to R Lundberg Cell 2 plan and sched.docx o LundbergLetter to Mr. Rusty June 17, 201 1 Page 3 Engineering Evaluation of Pump in Cell The Notice proposed that Denison would perform an engineering evaluation of the current pump in the Cell 2 access pipe to determine if any changes can be made to improve its efficiency and output, in light of the changes described above. Denison has completed an engineering evaluation of potential changes to the pump and made changes to the pump operation as described below to address DRC's preference that pumping occur more consistently at a lower flow rate over a nalTower range of solution levels. The slimes currently-installed drain pump is a Marinemate submersible pump Model 50TM2.45. The titanium alloy materials of construction are required to withstand the corrosive conditions in the cell slimes drain solution environment. Denison has previously used a number of other smaller pumps of other materials of construction in the slimes drain, with a resulting rapid corrosion and burnout of the pump. The currently-installed titanium-alloy model is the smallest (lowest flow rate) size pump available from any manufacturer in the appropriate materials of construction. In order to address DRC's concems, Denison has installed a reducing neck to reduce the pump discharge from 2 inches to I inch, this increasing the discharge head on the pump and reducing the discharge flow rate. The sensor settings (which trigger pump startup) have been adjusted from the former 0 feet to 4 feet setting to the current setting of 0 feet to 2 feet. As a result, the pump rate has been slowed sufficiently to allow the pump to cycle on for a longer time at a narrower range of solution levels, in effect, performing like a smaller PumP, as suggested by DRC. Amendment of the Groundwater Discharge Permit for Reduced Monitoring Frequency The Notice proposed that Denison would amend the Permit to adjust Part LD.3(b)(2) to reflect the changes in the monitoring of the Cell 2 water level, resulting from the installation of the piezometer(s) and approved monitoring procedure set out in the amended DMT Plan, and to reduce the frequency of monitoring from monthly to quarterly. As described above, Denison does not believe installation of piezometers to be feasible. However, as discussed with DRC, reduction in the number of sampling periods will reduce the number of days the pump is off to allow stabilization of levels to meet the data quality criteria in the DMT Plan, that is, will allow the pump to run for more days per year. As indicated in the Notice Denison believes a reduction in the monitoring frequency under the current pumping and monitoring regime will likely be sufficient to result in compliance with the Formula over time. Following DRC's approval of the plan included in this update letter, Denison would like to discuss with DRC a timetable for amendment of the permit to address the agreed-upon changes. ,)EH's$t{D#,d T}TINE$ I LundbergLetter to Mr. Rusty June l7,20ll Page 5 DBxrson Mrxrs (USA) Conr. Jo Ann Tischler Director, Compliance and Permitting cc: David C. Frydenlund Ron F. Hochstein Harold R. Roberts David E. Turk Kathy A. Weinel W d')/'Ltu OEH'5Oil$JJffINE3 DENlsOJY/ MINES Denison Mines (USA) Corp. 1050 lTth Stroet Suito 950 Denver, CO 80265 USA Tel : 303 628-7798 Fax: 303 3894125 wwwdenisonmines.com May 27,2011 VIA PDF AND FEDERAL EXPRESS Mr. Rusty Lundberg Executive Secretary Utah Division of Radiation Control Utah Department of Environmental Quality 195 North 1950 West salt Lake city, UT 84116-3097 Re: State of Utah Ground Water Discharge Permit No. UGW370004 White Mesa Uranium Mill - Notice Pursuant to Part I.G.3 of the Permit -Cell 2 Annual Slimes Drain Compliance Please take notice pursuant to Part I.G.3 of the White Mesa Mill's (the "Mi11's") State of Utah Groundwater Discharge Permit No. UGW370004 (the "Permit") and Utah Administrative Code ("UAC") R3l7-6-6.16(C)(1) that Denison Mines (USA) Co.p., as operator of the Mill and holder of the Permit, failed to meet the standards in Part I.D.3.(bX3) of the Permit, as described in more detail below. Facts and Background Information Part I.D.3(b)(1) of the Permit requires that the Permittee shall at all times maintain the average wastewater recovery head in the slimes drain access pipe to be as low as reasonably achievable (ALARA) in each tailings disposal cell, in accordance with the currently approved Discharge Minimization Technology Monitoring Plan ("DMT Plan"); Part I.D.3(b)(2) of the Permit requires that the Permittee shall conduct a monthly slimes drain recovery test at the Cell2 slimes drain that meets the following minimum requirements: (i) Includes a duration of at least 90-hours, as measured from the time that pumping ceases; and DRC- 20LL- CC6069 z#6o'-D}.$ Ru"#,^.\r R J(tN '' j. 3\<i - i.t't CJI fu,-r,ff# ::i,!1",, r:ll/\.>\Qu, errvE'D) ' 1. a) b) (ii)Achieves a stable water level at the end of the test, as measured by three consecutive hourly water level depth measurements, with no change in water level, as measured to the nearest 0.01 foot. Part I.D.3(b)(3) of the Permit requires that annual slimes drain compliance shall be achieved when the average annual wastewater recovely elevation in the slimes drain access pipe, as determined in the currently approved DMT Plan, meets the conditions in the formula (the "Formula") spelled out in Part I.D.3(b)(3) of the Permit. That Part also states that failure to satisfy the conditions in the Formula shall constitute DMT failure and non-compliance with the Permit. Section 3.l(bXviii) of the DMT Plan further states that 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 Permit, including the requirement to provide notification to the Executive Secretary orally within 24 hours followed by written notification. On February 25, 2011, Denison submitted its White Mesa Uranium Mill DMT Performance Standards Monitoring Report and Cell 4A BAT Performance Standards Monitoring Report for the 4th Quarter of 2010 (the "DMT Report"), in which it concluded that, on the application of the Formula, annual slimes drain compliance has not been achieved for 2010, in accordance with Part I.D.3 of the Permit. Denison first came to this realization while finalizing the DMT Report for submittal to the Executive Secretary. Denison also noted in the DMT Report that for the reasons detailed in the Report, Denison believes that the monitoring requirements of Part I.D.3(b)(2) of the Permit seriously interfere with Denison's ability to comply with Parts I.D.3(bXl) and I.D.3(bX3) and should be amended. Denison noted that the required monitoring prevented pumping of the slimes drain in Cell2 for approximately 77 days in 2010, or approximately 20o/o of the year. Denison also noted that the overall elevation measured from the first data point in 2009 to the last data point in 2010 indicated an overall reduction in elevation over the two year period, notwithstanding the fact that precipitation in 2010 was significantly higher than in 2009. Denison recommended that the monitoring requirement in the Permit be modified to allow the slimes drain pump sufficient running time to dewater the cell, and suggested as an example that the monitoring requirement could be reduced from monthly to quarterly. c) d) e) DENISOJ)// ,|ilNES g) This matter was discussed during a conference call held on lli4ay 25, 201I between Denison and State of Utah Division of Radiation Control ("DRC") staff. In particular, the parties discussed the impact the current monitoring requirements have on pumping, the possible need to amend the Permit to reduce the frequency of monitoring, the appropriateness of the Formula and whether or not any amendments to the Formula may be required, and a number of measures that could be taken in the field to improve the Cell 2 dewatering efforts. DRC staff advised that, notwithstanding these issues and the potential need to amend the Permit, Denison may be considered in violation of the Permit at this time. Denison and DRC staff agreed that Denison would provide this Notice to the Executive Secretary setting out Denison's plan and schedule for addressing this matter. This Notice is also intended to more formally provide the information contemplated by the 5-day written notice requirement under Part I.G.3 of the Permit relating to this matter. 2. Actions Taken At this time Denison is continuing to pump and monitor the Cell 2 slimes drain in the same manner it has since prior to the beginning of 2009. Included with this Notice is a figure that shows the monthly Cell 2 slimes drain elevations, in Feet Below Top of Standpipe, from January 2009 through May 2011. It is evident from a review of the figure that the most recent monthly result, May 2011, is lower than the last result reported for December 2010, although there continues to be variability from month to month. Further, the overall trend in the data since the beginning of 2009 continues to be downward, which suggests that the Formula may not be adequately capturing this trend. This trend also existed from January 2009 through December 2010, although not as pronounced over that shorter period of time. The failure of the Formula to adequately track this downward trend may result from the fact that the four years of data required as inputs into the Formula will not be available until the end of 2012 or from some other feature of the Formula that may need to be addressed. 3. Actions That Wiil be Taken to Prevent a Reoccurrence of this Incident Denison believes that a reduction in the monitoring frequency under the current pumping and monitoring regime will likely be sufficient to result in compliance with the Formula over time, although possibly not by the end of 2011, given that half the year has already passed. Therefore, Denison proposes that the following additional actions, over and above a reduction in the frequency of monitoring, also be taken to provide more assurance that a reoccurence of this incident will not occur: DENISOJ)I/ MINES a) Denison will re-grade the interim fill on Cell 2 in order to reduce the potential for the accumulation of stormwater on the surface of Cell 2, which can potentially infiltrate into Cell 2. This re-grading will be completed on or before August l,20ll, which is expected to be prior to the start of the late summer Monsoon season; b) Denison will install one or more piezometers into Cell 2 for the purposes of monitoring the water level in Cell 2 in lieu of continued monitoring of the Cell 2 slimes drain access pipe. This will allow for the pump that is located in the access pipe to operate without intemrption from monitoring activities. Denison will submit a plan and schedule to the Executive Secretary on or before June 17, 20ll that will address the plan and schedule for installing such piezometer(s). That Plan and Schedule will contemplate that the current DMT Plan be amended, with the Executive Secretary's approval, to reflect the manner of sampling the piezometer(s) prior to commencement of monitoring. The piezometer(s) will be installed within 30 days after Executive Secretary approval ofthe Plan and Schedule; c) Denison will perform an engineering evaluation of the current pump in the Cell 2 access pipe to determine if any changes can be made to improve its efficiency and output, in light of the changes described above. The results of that evaluation will be described in the Plan and Schedule referred to in paragraph b) above; and d) The Permit will be amended to adjust Part I.D.3(b)(2) to reflect the changes in the monitoring of the Cell2 water level, resulting from the installation of the piezometer(s) and approved monitoring procedure set out in the amended DMT Plan, and to reduce the frequency of monitoring from monthly to quarterly. The Cell 2 water level will continue to be monitored in accordance with the current Permit conditions and, after amended, the amended Permit conditions, through the remainder of 2011. The monitoring results for 2011 will be compared to the results for previous years through application of the Formula, and the comparison will be submitted to the Executive Secretary in the DMT Report for the 4th quarter of 2011, which must be submitted on or before March l, 2012. If the conditions in the Formula are satisfied, then Denison will continue its dewatering activities in 2012 and subsequent years in accordance with the amended Permit conditions and will continue to compare the results annually as contemplated by the Formula. If the conditions in the Formula are not satisfied for 2011, but it appears from a review of the results that the measures described in paragraphs 3 a) through d) above have been working to improve dewatering activities after August 2011 and if implemented for a full year would appear DENISOJ)// ,YIINES to be likely to be successful in meeting the conditions in the Formula, then the Executive Secretary will determine whether to exercise his discretion to allow the pumping and monitoring to continue in the same manner through the rernainder of 2012, after which the results for 2012 will be compared to the results for previous years using the Formula. If the conditions in the Formula are not satisfied for 20l l and the Executive Secretary does not exercise his discretion as contemplated by the previous paragraph, then either: e) The Executive Secretary and Denison will review the Formula to determine if it is appropriate to determine if the pumping is maintaining the average wastewater level in Cell 2 as low as reasonably achievable ("ALARA"), u. contemplated by Part I.D. 3(b)(1) of the Permit, and if not agree on appropriate modifications to the Permit; or 0 The Executive Secretary and Denison will consider further field activities that may be performed in order to achieve the ALARA goal contemplated by Part I.D.3(b)(l) of the Permit and a Plan and Schedule for implementing any such activities, and the Permit will be amended to reflect the foregoing. 4. Affirmative Defense Denison believes that the failure to meet the conditions of the Formula was caused by the monitoring requirements of the Permit, which prevented the ability of the pump from being active for 20o/o of the time. This amount of pump downtime was not contemplated by the Permit. This is almost twice the downtime that would result from the pump being off for the 90 hours per month contanplated by Part I.D.3(b)(2) of the Permit. As a result, Denison believes that its inability to be able to comply with the Permit conditions was caused by the Permit itself and not by its own actions or inactions. However, if any potential violation were to be identified, Denison believes that the affirmative defense in Part I.G.3.(c) of the Permit should be applicable to this incident, for the following reasons: a)Notification Oral notification was not given to the UDEQ Duty Officer within 24 hours of the discovery (which was made at the time the DMT Report was being prepared for submittal to the Executive Secretary on February 25,2011). However, written notice was given to UDEQ within 24 hours of the discovery through the submittal of the DMT Report. Further, this Notice is being given by Denison within five days of the i|lday 25,2011 conference call during which DRC staff advised that they thought this matter may constitute a violation of the Permit. Although the oral notification was not given, Denison submits that the written notifications given to the Executive DENISOJ)//MINES Secretary in these particular circumstances constitute substantial compliance with the notification requirements of Part I.G.3 of the Permit and Section 3.1(b)(viii) of the DMT Plan. Denison has noted, however, that in future circumstances such as these it will also provide the 24 hour oral notice and will ensure that the written notification is given in a stand-alone notice within 5 days of the oral notification. b) Failure was not Intentional or Caused by the Permittee's Neeligence The failure to satisff the conditions in the Formula was not intentional or caused by Denison's negligence, either in action or in faihne to act. Denison continued to perform the pumping and monitoring that is contemplated by the Permit and the DMT Plan and that it had been performing over the last several years. Denison believes that the excessive pump downtime caused by the frequency of monitoring has prevented Denison from meeting the conditions in the Formula. Further, given the variability of the water levels, it has been difficult to predict annual results prior to year end, based on monthly results or even cumulative month-to-date results at any time during the year. It was therefore not possible to predict with any certainty during the year whether or not compliance would be achieved for the year. c) The Permittee has Taken Adequate Measures to Meet Permit Conditions Denison believes that the proposed measures described in Section 3 above will be adequate to meet Permit conditions in the future. d) The Provisions of UCA 19-5-107 Have Not Been Violated The provisions of Utah Code 19-5-107 have not been violated. There has been no discharge of a pollutant into waters of the state. Denison has not caused pollution which constifutes a menace to public health and welfare, or is harmful to wildlife, fish or aquatic life, or impairs domestic, agricultural, industrial, recreational, or other beneficial uses of water, nor has Denison placed or caused to be placed a.ry waste in a location where there is probable cause to believe it will cause pollution. Please contact the undersigned ifyou have any questions or require any DENISOJ)// ,YIINES furthet information. cc:Ron F. Hochstein Harold R. Roberts Jo Ann S. Tischler David E. Turk Kathy A. Weinel Regulatory Affairs and Counsel DENISON]YI TUIINES ao ITOZ/OE/9 TIOZIT€./S t10z/0Eln tt1z/tE/E ttoz/8zlz rrozlttlr 0t0zlrElzr OIOZIOEITT 0t0zltE/0r fi\zl0e/6 orozlTe/8 0t07.ltElL 0t0zl0E/s otlzlrE/s 0r0zl0Elv owzlwle oro7./82/z OIOZlTEIT 6002/tElzr 600zl0Elrt 6002/rEl0t 600zloel6 600zltEl8 600zltElL 600zloEl9 600zlrEls 6002/oElv 600ZlIEIE 6002/8zlz 6002/oElr Nqo'tr o.)I (!oc J I r{doNdoF{oN orooN I .s(uLo tao .E Ih N oI N o'troCI + (o60 d edldpuels lo dol mo;ag 1aa1 tsR C- 2rl 1-,g"g.*.,0,^g,p ;'{or"i12-,si}',' .,,';'*' A "'.di, i'i! Received i3\ lI JAN zor r E)\1 Division of S/t,)., Radiation Control ,tl;,\?,.,- "i;'l/'-.i',lrrrgi:YJanuary 10,2011 VIA E.MAIL AND OVERNIGHT DELIVERY Mr. Rusty Lundberg Utah Department of Environmental Ouaiity 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 Transmiftalof Revised Documents A?dressing 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 UDEO 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 thit the Contingency Plan will be addressed separately and changes will not be tied to approval for use of Cell 48 or the New :Decontamination Pad. DRC received the October 11,2010letter requesting changes to previously'submitted versiirns of the DMT Plan BAT O&M Plan, and Contingency Plan. To address those comments and other changes necessary for operation of Cell 48, Denison submitted on November 12;2010 redline and clean copy revisions of those documents entitled DMT Plan Revision 1 1, 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 letterof January 6,2011. Denison has accepted allthe 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 UDEO 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. DENrsohsdd MINES t050 ,l7th Street, Suite 950 Denver, CO 80265 usA Tel :303 828-7798 Fax :303 389"4125 www.denisonmines.com N:\Cell 4B\January 2011 Submithls and Revisions for Cell 48\01.10.11 lp6ns6ittal to DRC Plan Rerrisions for Cell 4B.doc Lefter to Mr. Rusfy f-rrOO"rP January 12,2011 Page 2 We have also provided , below,specific responses to each request in UDEQ's January 6,2011 letter fhe secfions and numbering of the remainder of this lefter 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 Continoencv Plan fi 12010 Revision: DUSA-4\ P/ease be aware.that in order,to expedite the Cett 48 review process, that DRC rcview of,the Contingency Plan will be addresse d under separate cover, proceed independently, and nott be tied to the use ofrthe NDP nor Cell 48. The following is noted for,future reference: A. tn the subject-November,12,2010 tefter, DIJSA provides proposed red-line and clean yersions oftthe Contingency Plan version noted, which inctude aspecfs rcgaiding Cell48. B. The third paragraph as well as Section 2 .a.1 ofra September? ,2010 DUSA /efter discusses contingency plan comments in our,May 10,2010letter. Denison Response: No response required. : The DMT.Plan fi1f2010 Revision: DUSA-I1 1. We acknowledge a section oftparagraph 3 .1.e.i D has been changed appropriately to read that, ". . . The depth to water'from the top . . . oftany oftthe three (3) obseruation pofts to the standing water, shall be no /ess than 6.2 feet." lt appears that incorporation ofrthis item into an approved DMT PlanwouldcompletefheissuesregardingtheNDPwithrdspecttoDMT'Ptanadjustmenfs.' Denison Response: No response required. 2. The DMT Plan (as well as the O&M Plan), incorporating necessary items for, Cetl 48, must be approvedpiorto DRC authorization oftuse forCell4B. Regarding freeboard requirements, the Ptans proposed by the subiect DUSA November'12, 20l0lettermake the assumption that:Cell48 is cunently authoized for use, and it is not necessary to estabf'sh a freeboard forCelt 4,A. However, fhis is incorrect. This . approach DUSA has taken appears fo necessltate one oftthe following: a. That the last action prior'to authorizing use of,Cell 48 must be the approval of,the DMT Ptan (and the O&M Plan), orb, To obtain approval oftthe DMT and O&M Plans now, DUSA change the ptans to estabtish the freeboard for,Cell 4A. to be one ofrthe following, either. ('1). The fixed freeboard elevation for,Celt 4A,6stablished by the DRC freeboard vaiance 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 appticable, would be esfab/ish ed by the igorous freeboard calcutation method outlined in foimer,ptroposed P/ans, but would be witten such that iftCell 48 becomes approved, thatthe freeboard determination method would no longerbe needed for,or,apply to Cell4A. Ptease provide DRC yourdecision to us in this regard, togetherwith any and allnecessary conesponding changes to the DMT Plan. DENISOJ)I/illlNEs Letter to Mr. Rusty nnaO} January 12,2011 Page 3 Denison Response: Denison has chosen option (a.) above and will request the approval ofithe DMF Plan and the Q&M Plan as the last aclion prior to the UDEQ authorizatiori for the use of Cell48. As such, the changes requested regarding the reintroduclion ol Freeboard limits for Cell 4A aie not necessary. 3. The fottowing changes in DMT Ptan forms, retated to tailings beach elevations, are needed due to the need to measure beach elevations in tailings Cells 4A or48, as applicable ( perparagraph 2 above). Ihrs issue was brought to your attention eadier in our,letter dated October 1 1 , 201 0. The freeboard for these ponds is determined from the use oftsuch (see paragraph 6.3 and Appendix F of,the DMT Ptan): a. On page 28 of,49 in Appendix A of,the submitted clean copy of,the Ptan:(1) The heading numbered as one, near,the left margin on that page; must state'Pond and Beach elevations . . . ," the following eartier,proposed DMT Plan versions also contained this provision; (a). 12/0E Revision: Denison-7, (b). 05/09 Revision : Denison-E, and (c). 3/rl 0 Revision:Denison-9. (2) tn the conesponding page of,the submitted redJine version ( i.e. page 33 of,56), item number, one contains secfions for,Cell 44. 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 foreach of, fhese cel/s, as applicable with paragraph 2 above. (Earlier proposed DMT Plan Versions contain this item (d) forCell 44, in the versions given in paragraph 3.a. above). b. Section 3.l.d.vii, paragraph C shoutd be labeled as paratgraph B. The title of'this paragraph should be 'Cell 4A or48 Beach Elevation," as needed and applicable with paragraph 2 above. The body of,that paragraph should indicate that the beach elevation suruey will be in Cell4.A, or,Cell 48 as applicable. (lf,Cell 48 becomes approved for, use, it then wilt be is no tonger, necessary to estabtish freeboard elevation forCell4A). Denison Response: g.a.fi) The heading has been changed as requested. 3.a.(2) fhe requested text "Elevation of' Beach Area with the Highest Elevation (monthty)," has been added to Cell 48 only. As previously stated, Denison is requesting UDEQ agproval of the DMf Phn as the last action prior to the use of Cell 48, and as such the requested change to the Cell 4A weekly inspection is not necessary. 3.b. See response to 3.a.(21above. 4. Ptease correct miscetlaneous errors noted at the fottowing locations on the subject submitted redtine DMT Plan copy: a. The third paragraph ofipaee 2, and in paragraph a) betow it, the detetion and relocation of,a sentence ls erroneousb. Last paragraph oftpoee 3, the elevafions /isfed for,the towest points on the flexible membrane liners for,Cells 4A and 48 conflict with the elevations listed in Appendix A (page 33 of,the redline copy) for Cells 4A. and 48.c. On page 11 heading lll, (used for,the Roberfs Pond) should be a heading lV. oEN'soJ)/lItiINES Lefter toMr, Rusty tunOOer! January 12,2011 Page 4 d. ln Section 6.3, the fifth paragraph, the first number,in the parcnthetical phase appears it should be ':r';':;:y;:;ilfJ'ri"r, copy, corresponding to p. 33 onthe red-tine copy, ror,cer 4A the FML bottom elevation line needs to be rightljustified. On page 33,paragraph number,2 , the statement "Pump Timer set at15 min on ...," needs to be deleted.g On page 36, the asterisk footnote shown refers to an elevation which appears to apply onty to Cetl 44. The footnote needs to be adjusted somehow include the elevation that applies to Cell 48 as well. Denison Response: Iiese changes have been made in fhe affached DMT,Plan Revision 1 1.1. The Celt 4A & 48 A&M Plan. 11/2010 Revision Denison 2.A. oftthe submitted red-tine copy: l. Figure6B does not fottow the same logic as Figure 64 t.e., the lowest FML elevatiotn aboiue the sump level is not 1.*feet above the sump bottom (for the 1?-inch diameter collection pipe) as in Figure 6A. Please explain and justify this difference.ll. On page I l, in two separate paragraphs numbercd I and 2, the second and the /ast sentence respectively, contain a parenthetical phase that must be deleted or,adjusted, as rt r.s incorrectlll. On page 14, in the third sentence the parenthetical phrase must be deleted or, adjusted, as if rs , incorrect. tV. Atso, on pa'ge 14, the second fo /asf sentence from the boftom oftthe page, beginning with, "Each pump is equipped with...," refers to disfances oft2.25 feet and 9-inches. Ihese distances appear,to not be appticable for,the Cett 48 sump and respecting Figure 68, P/ease revr.se this senfence and or figure, to be correct for Cell 48 as well.V. On page 15, the /asf senfence,ofihe first paragraph on that page must spectfy what Figure it refersto. : Vl. Page 17, the third paragraph stafeq " Condition 70.3 stafes that...," however, cunent !-icense Condition 10.3 does not state the verbiage quote.! after,that sentence. Please adjust this paragraph with the proper,references and verbiage, as applicable. Vll. Beginning on page 17, rewrite the section oftthe O&M Plan titled "Cell 44 Solutioi Freeboard , : Catculation," including the title ofihat sectrbn. This will need to be done according to DUSAS application oftthe paragraph numbered 2, under,the DMT,Plan comment sec0bn oftthis letter, Vlll.Please conect miscellaneous errors noted at the following locations on the subject redJined copy oft the Cell44 and 48 BAT,O&M Plan: a. On page 6 , paragraph .2, add a sentence which describes fhat the non=woven geotextile materialrs a/so overlain at the surface by a woven geotextile fabric, which is ballasted latenlly by sandbags on each side ofrthe backbone gravel berm.b. The above item also must be added to pamgraph 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 materialrs also overlain at the surtace 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 'DMT,Monitoring Plan. : . Denison Response: e. fl DENISOJ)I/ I}IINES ondbergLetter to Mr. Rusty Lu January'12,201'l Page 5 l. Figure 68 is correct. The lowest FML above the sump level is 2.06 feet for Cell48.ll. The phrase has been deleted from both paragraphs as requested.lll. The phrase has been deleted as requested.lV. The text has been corrected to reflect the actual conditions in Cell48 as shown in Figure 68, which is correct.V. Figure 5 was referenced in the previous version and no correction is required.Vl. The conect verbiage has been added. : : Vll. See response to 3.a.(2) above.Vlll. ltems 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, Deusoru Mrues (USA) Cone. Director, Compliance and Permitting cc: David C. Frydenlund Harold R. Roberts David E. Turk K. Weinel Centralfiles DENISOJ}/I MINES Statp GARY R. HERBERT Govetnor GREG BELL Lieutenant Govemor TO: THROUGH: FROM: DATE: SUBJECT: Department of Environmental Quality Amanda Smith Executive Director DTVISION OF RADIATION CONTROL Rusty Lundberg Director MEMORANDUM DRC- 20L2-OO TTB4 Rusty Lundberg / ,/ Phir Gobre ?b z/ts/zarz David Rupp flZZ -February 16,2012 Denison Mines Tailings Cell2 Slimes Drain Recovery Results for: Calendar Years 2009, 2010 and}0ll References: a. DRC MEMO dated May 3, 2011, subject: Decision Paper for Possible NOV; DUSA Exceedance of Ground Water Discharge Permit Elevation Requirements for Dewatering of Tailings Cell No. 2; Fourth Quarter, 2010 DMT Monitoring Report. b. DRC Transmittal Letter dated Dec. 20,2011. subject: Same as above, Failure to Meet Affirmative Defense Requirements and Draft Stipulated Consent Agreement. c. DUSA Letter dated January 27,2012, subject: Failure to Meet Affirmative Defense Requirements Cell2 Slimes Drain Recovery Elevation. d. Ground Water Discharge Permit for DUSA, Part I.D.3. As you are aware, DUSA is in process to dewater Tailings Cell2 at DUSA. To date, this process has consisted of pumping and diverting water from a "slimes drain" system and placing temporary soil cover over the tailings cell. The slimes drain system is a drainage system above the synthetic liner in the bottom tailings cell. The intent of the slimes drain system is to collect and allow the removal of residual water inventory from the system via a single access pipe. Therefore, when pumping ceases for a sufficient time, the access pipe acts as a piezometer and the water surface becomes static. This static level is known as the slimes drain recovery elevation (SDRE). The elevation of the water inventory in the cell is determined by stopping the pump for a sufficient time, then measuring the distance from a known elevation at the top of the access pipe to the static water surface. Temporary soil covers have been placed on Cell 2 prior to 2006 and in 201 1 , to divert storm water off the cell, and prevent it from becoming part of the water inventory below the surface. I 95 North 1950 West . Salt t ake City, UT Mailing Address; P.O. Box 144850. Salt [ake City, UT 84114-4850 rerephone (801) 536-42s0 .7:f}ir"ijr;!ie7 . r.D.D. (801) s36-.1414 Printed on 10070 recycled paper Page2 The permit, reference (d), requires the average annual slimes drain recovery elevation to decrease each year, and to be calculated by using a moving 3-year annual average. DRC is now in possession of figures for three distinct 3-year annual averages of the slimes drain recovery elevation (SDRE) for Cell 2 at DUSA. These figures are given in feet above mean sea level (fmsl). These average SDREs,-corrected for survey errors, are as follows: Calendar Year 3-vear SDRE Annual Averase 2009 5600.16 fmsl 20to 5600.25 fmsl 2011 5600.00 fmsl For 2010 DUSA reported the rise from 5600.16 to 5600.25 fmsl. This 1-l/8 inch rise in the average annual SDRE elevation is a violation of the permit. This event is. documented in references (a) and (b) above. DRC also proposed a stipulated consent agreement (SCA) to DUSA via reference (b) to encourage DUSA to come into compliance with the permit beginning in 2011 and future years. DRC chose this approach rather than issue an NOV for the violation in 2010. DUSA demonstrated in reference (c), dated Jan. 27,2OI2, that for 2011 the average SDRE decreased to 5600.00 fmsl, or dropped 3-inches. Thus calendar yezr 2011 is in compliance. DUSA has stated there is no need for a SCA, as they are now in compliance. I tend to agree with them at this point. Therefore, as far as the average annual SDRE is concerned, I suggest we issue an NOED for the 2010 violation, and watch future annual reports. If DUSA is ineffective in future years in coming into compliance, we can reissue the SCA for DUSA's consideration or take other action. -END- {n & /i"neelh utr'/h P'lnn#ny Yt'? 2/22h' l. /i fibafuJ fita{ an t/ooo B;'/ neeJeJ ' 7hr} ls bu, ause, a4 o/era-il o/."nor. /; €DR€ las yccuhre.d 4ro- ''ooq h zo // 4-b , (See. ab'rc) . Page I of2 Phillip Goble - Re: Fwd: Denison Response to Ce!! 2 Slimes Drain Recovery Elevation From: To: Date: Subject: CC: Loren Mofton Phillip Goble 2l3l20LZ B:04 AM Re: Fwd: Denison Response to Cell 2 Slimes Drain Recovery Elevation Dave Rupp; John Hultquist; Rusty Lundberg Phil, Dave Rupp sent me a copy of the DUSA response. I have a few questions / thoughts for you to consider: 1. What are the next steps for DRC on this? Looks like Dave Frydenlund wants to avoid a consent agreement. 2. They extended the vertical slimes drain access pipe - has anyone verified what they really did? Have our staff done any field inspections, i.e. measured the new depth of the access pipe and compared it to the former total depth? Where is the recovery water level elevation now, and how does that compare to previous elevations. It's important that extending the pipe not be used as a ruse to come back into "compliance" on the slimes drain water level recovery elevation. 3. Adding more temporary cover to Cell 2 should have increased the static load on the tailings, decreased the porosity, and increased the leachate water level elevation. This transient response, should make more water available inside the access pipe for removal (per hour), but given the low permeability of the tailings and the fact under-drain piping system is so limited across the floor of Cell 2, it may take a significant amount of time for the water level elevations to return to a steady state, and decline to levels that are below where they previously were. In other words, water levels may rise before they start to fall (get better) again. Have we seen any corresponding transient response in the recovery water level elevations (rise or fall)? 4. It is apparent that they are putting all their marbles on re-grading the temporary cover, as a means of denying stormwater accumulation and recharge to the cell. That is fine, but they are ignoring what the added load will do to the water levels. Almost Final Thought: overall, increasing the density of the tailings to provide a stable platform for the cover system is our primary goal (Job 1). Next to that, getting a final cover system constructed is Job 2 (to deny infiltration / radon emanation). Leachate removal along the way is a side benefit - although important for GW protection. Considering Sarah Fields'comments regarding interim milestones for DUSA reclamation, we may be able to provide more protection to the environment, by changing the strategy in the Permit / License to focus on tailings settlement monitoring, and setting deadlines for completion of cover construction. FinalThought (really): improved slimes drain design / performance in future construction is critical. What do you think? Loren >>> Phillip Goble 1/30/L2 LL:44 AM >>> See the attached. >>> Rusty Lundberg tl30l20L? 7:48 AM >>> FYI file:/iC:\Documents and Settings\Pgoble\Local Settings\TempU(Pgrpwise\4F2B95lAEQDO... 21612012 >>> KathyWeinel <KWeinel@denisonmines.com> Ll27l20L2 5:27 PM >>> Mr. Lundberg, Attached please find Denison's Response to DRC's Letter regarding Failure to Meet Affirmative Defense Requirements Cell 2 Slimes Drain Recovery Elevation Utah Ground Water Discharge Permit UGW370004. Please contact me if you have any questions on this transmittal. Yours truly, Kathy Weinel Page2 of2 DENTSON MINES (USA) CORP !4M1"'/-.denls!runl,1_es.*cgm Kathy Weinel Q u a I ity Assurance M a n a ge r t: 303-389-4'1 34 | f: 303-3894'125 1050 17th Street, Suite 950 Denver, CO, US, 80265 This e-mail is intended for the exclusive use the of person(s) mentioned as the recipient(s). This message and any attached ,iles with it are confidential and may contain privileged or proprietary information. lf you are not the intended recipient(s) please delete this message and notify the sender. You may not use, distribute print or copy this message if you are not the intended recipient(s). file://C:\Documents and Settings\Pgoble\Local Settings\TempU(Pgrpwise\4F2B95IAEQDO... 21612012 lbnvcrs.F"oo,J /' 24' /2 . - frorlv9ua,rs"f , ?t!sA;3c{ L/, ,bD,Ec,%p".zol/ !'sr4e oe// ?- R"rt infrmol. Ho Ai:'-i:hi,'frr/*, /noJ /^t c o /t7d?td h{ fi,??, b so, I ,Yri F, h.;J, ol"ful il,*t?IA Ddt hoa i; comF/,;rre' usrlk lha SDZ,6 raX*r/s, f" cyzotl- flust, euJ we uill rerriw /hd, ,q,or{ ortr,n ;{ a,,,va it* liu SwE cL , *" u;U, rt,,/ &/rZ* ,r,/,"tt afi,A rt fr/* /-d"rl- c,- fi,,o- % f d^* '#, ,/o. t State of Utah CARY R. HERBERT Govemor CREG BELL Lieutenant Governor Department of Environmental QualitY Amanda Smith Executive Director DTVISION OF RADIATION CONTROL RustY Lundberg Direcror December 20,2011 David C. Frydenlund Vice President and Counsel Denison Mines (USA) CorP.(DUSA) 1050 17th Sfieet, Suite 950 Denver, CO 80265 Dear Mr. Frydenlund: SIIBJECT: Cell2SlimesDrain RecoveryElevation Requirements Utah Ground Water Discharge Permit UGW370004: Failure to Meet Affirmative Defense Requirements [Part I.G.3(cX3)] and Draft Stipulated Consent Agreement Division of Radiation Control (DRC) representatives havq reviewed the February 25,20L1 Denison Mines (USA) Corp. (DUSA) DMT Perfotmance Standards Monitoring Report and Cell 4A BAT performance Standards Monitoing Report for the 4th Quarter of 2010. It has been determined the facility is not in compliance with a Discharge Minimization Technology (DMT) requirement in part f.b.g@)t:) of thi subject Groundwater Discharge Permit, as it relates to the required decreasing annual 3-year average water level elevations in the Cell 2 slimes drain observation pipe. This conclusion is supported by the February 25,2011 DUSA report that states "...annual slimes drain compliance tras not been achieved for 2OlO, in accordance with Part I.D.3 of the Permit." DRC has also reviewed DUSA letters dated May 27, June 17, and August l,20ll in regard to this matter. The review shows that none of these letters fully meets the Affirmative Defense requirements found in Part I.G.3(cX3) of the Permit, in that: l. In the May 27,2011 letter DUSA made a commitment to improve the Cell2tailings water level monitoring by installing multiple piezometers in the tailings (ibid, p. 4, Item b). DUSA and the DRC (parties) agreed upon this monitoring improvement during a May 25,2011 telephone call. Then, in letter dated June 17, 201I DUSA unilaterally ietracted this commitment on the basis that piezometers would experience 195 North 1950 west'Salt l,ake City' UT Mailing Address: P.O. Box 144850 ' Salt Lake City, UT 84114-4850 Telephoni (801 ) 536-42s0 . Fax (801 ) 533-4097' T.D.D. (801 ) 5364414 www.deq.utah.gov hinted on 100% recYcled PaPer i,f'\n CERTIFIED MAIL Page2 artesian conditions, be difficult to maintain, and not be representative of head conditions in the Cell2 tailings or slimes drain. These arguments were repeated in the August l,2}ll DUSA letter. After review of this matter, we find that DUSA withdrawal of the agreed on improvement to head monitoring raises significant concerns. We acknowledge your preferred actions, that being a decrease in frequency of recovery testing (and related gain in pumping efficiency), and re-grading of the tailings surface. However, due to possible small gains from this work, we have little confidence that these actions alone will result in a substantive and sustained decline in the Cell2 tailings solutions levels, and ultimately prevent or minimize the potential for groundwater pollution Further, in a May 25,2}ll telephone call we discussed other options available to actively remove water from the Cell2 slimes drain, including, but not limited to addition of a series of pumping wells and/or vertical wick drains in the tailings, etc. To date, you have declined to consider such active alternatives that would lead to definitive reduction of wastewater elevation and inventory in Cell 2. None of the letters from DUSA provides a definite date by which the annual water level trend in question will come back into compliance with the requirements of Pan LD.3 of the Permit (to have a decreasing water level trend). Instead, DUSA has expressed their opinion that at some future date the Co-Executive Secretary should consider enforcement discretion and/or agree to modify Equation I in the Permit. This is premature and not appropriate in that: a. Future water level data has not yet been collected and evaluated by DUSA, and shared with the DRC; and b. DUSA has failed to provide a definitive determination of all the physical, mechanical or hydraulic factors that control water levels in the Cell2 Slimes Drain; nor has DUSA provided any justification of how many of these are controlling or sensitive to solving the non-compliance. c. Uncertainty in the effectiveness of the DUSA proposed action raises ongoing concerns. Because of this lack of deadline and justification, the DUSA responses appear to: a. Avoid operational responsibility for the increased water level trend observed in Cell2, b. Fail to take the opportunity to maintain more of the wastewater inventory in the more advanced and robust tailings Cells 4A and 48, and c. Delay efforts to prepare Cell2 for reclamation, thus deferring these costs to some future date. In light of these findings, DRC has determined it will not approve the DIJSA proposed actions, pursuant to Part I.G.3(cX3) of the Permit. As a result, DUSA has been unsuccessful in defending itself against enforcement action at this time. ? 2. 3. t ;:;:end, a draft stipulated consent agreement (scA) is attached for your review and comment. The DRC is providing OUSA this opportunity to negotiate and sign this voluntary SCA in order to resolve this matter without further administrative proceedings. please give this letter and the enclosed SCA your immediate attention. In the absence of your ,rrp"nr" to this letter prior to January 3l,2\L2,we will consider other administrative altematives. If you wish to discussihe draft SCA, we are available for a conference call or meeting in Salt Lake City. please contact me (801-53 64257) or Loren Morton of my staff (801-536-4262),to arrange for a discussion. UTAH WATER QUALITY BOARD T'Yl-6-l; Rusty Lundberg, Co-Executive Secretary RL:DAR:LBM Attachment F:UDUSA\NOVs\SCA Xmtllrr l2'20ll.M Fllc: DUSA GW Pcrmit EnforcenPut UTAH WATER QUALITY BOARI) DRAITT IN THE MATTER OF DENISON MINES (usA) CORPORATION 105017th Street, SUITE 950 DBNVER, COLORADO 80265 DOCI(ETNo.ucwll-06 STIPI.]LATED CONSENT AGREEMENT This STIpULATED CONSENT AGREEMENT ("AGREEMENT") is between DENISON MINES (USA) CORP. ("DUSA") and the UTAH WATER QUALITY BOARD ("BOARI)"), conceming violations of the Utah Water Quality Act, ("Act"), including sections 19-5-104, -106, - lll and -115, Utah Code Annotated ("UCA") and in accordance with the Utah Administrative procedures Act, UCA 63G-4-101 to -601 andthe Utah Environmental Quality Code, UCA 19-1-301. l. The BOARD has authority to administer the Utah Water Quality Act. 2. The CO-EXECUTM SECRETARY of the BOARD (hereinafter the "EXECUTM SECRETARY") will administer the terms and provisions of this AGREEMENT. Utah Code Ann. $ 19-5-115. 3. The parties wish to resolve this matter fully without further administrative proceedings except to the extent provided herein by entering into this AGREBMENT. 4. This AGREEMENT does not in any way relieve DUSA from any other obligation imposed under the Act or any other State or Federal laws, rules and regulations. 5. DUSA accepts the following facts and stipulations: A. DUSA owns and operates a facility located approximately 6 miles south of Blanding, Utah on White Mesa in Sections 28,29,32, and 33, Township 37 South, Range Z?East, Salt Lake Baseline and Meridian, San Juan County, Utah. The DUSA facility receives and processes natural uranium-bearing ores including certain specified alternate feed materials, and possesses byproduct material in the form of uranium waste tailings and other uranium byproduct waste generated by the licensee' s milling operations. In accordance with the requirements of the Utah Administrative Code (hereinafter "UAC") Ground Water Quality Protection R317-6-6.4(CX3), "[t]he Executive Secretary may issue a ground water discharge permit for an existing facility provided: ... 3) the applicant utilizes treatment and discharge minimization technology commensurate with plant process design capability and similar or equivalent to that utilized by facilities that produce similar products or services with similar production process technology ..." In accordance with the requirements of the UAC Ground Water Quality Protection R317-6-6.14, "[i]f monitoring or testing indicates that the permit conditions may be or are being violated by ground water discharge operations or the facility is otherwise in an B. C. D. E. F. out-of-compliance status, the permittee shall promptly make corrections to the system to correct all violations of the discharge permit." Utah Ground Water Discharge Permit No. UGW370004 ("Permit"), was originally issued to DUSA on March 8, 2005; the Permit was last modified on July 14,2}ll. part I.D.3.(bX3) of the March 17 ,2008* Permit issued to DUSA defines Discharge Minimization Technology ( "DMT") performance standards and states as follows: "Annual Slimes Drain Compliance - shall be achieved when the average annual wastewater recovery elevation in the slimes drain access pipe, as determined pursuant to the currently approved DMT Monitoring PIan, meets the conditions in Equation 1..." In turn, Equation 1 is defined in Part I.D.3 of the Permit, and mandates: i) monthly measurement of the slimes drain recovery elevation ("SDRE"); ii) calculation of a 3-year running average of the SDRE; and iii) that the overall average SDRE for the most recent year (hereinafter "Y"), and rhe 2 previous years (Y-1 and Y-2) is LESS than the average SDRE for the previous 3 year interval, i.e. the running average for years Y-l,Y-2, and Y-3. In other words, DUSA is required to demonstrate a declining trend in 3-year running average SDRE values. * The declining annual 3-year running average SDRE requirements at Part I.D.3(b)(3) and Equation I became effective upon execution of the March 17,2008 Permit, and have remained in force since. The Permit change was first proposed by the Utah Division of Radiation Control (hereafter "DRC') in a Draft Permit dated October 24,2007. The Draft Permit was made public for comment between late October and November 28,2N7. On November 27,20A7, a public meeting was held to receive public comment on the Draft Permit. A detailed chronology of the SDRE testing requirements and the new performance standards of the Permit were found in the october 24,2007 DRC Statement of Basis (pp. 7 -8). During the public comment period, no written or verbal comments were received from DUSA or any member oi the public per March 14, 2008 DRC Public Participation Summary. G.In a letter dated February 25,2011, DUSA provided the DRC with the results of their Annual Slimes Drain Compliance efforts in a combined report titled, DMT Perfolmance Standards Monitoring Report and Cell4A BAT Performance Standards Monitoring Report for the 4tr quarter of 2010. This report includes, in part, the following information: i). The last determination of the Tailings Cell 2 SDRE for 2010 was completed on December 20,2010. ii). The conditions in Equation I had not been met at Tailings Cell 2, and "...annual slimes drain compliance has not been achieved for 2010, in accordance with Part I.D.3 of the Permit. iii). A recommendation that, "the monitoring requirement in the Permit be modified to allow the slimes drain pump sufficient running time to dewater the cell. For example, the monitoring requirement could be reduced from monthly to quarterly." Part I.G.3(c) of the Permit provides DUSA an opportunity to affirmatively defend itself against enforcement action, in the event of a DMT or BAT failure, provided four conditions are met, as follows: i) DUSA must provide 24-hour verbal and 5-day written notice of the non- compliance; ii) The failure or non compliance was not intentional or caused by negligence, either in action or inaction; iii) DUSA has already taken adequate measures to meet all Permit conditions in a timely manner, or has submitted for Executive Secretary approval;'an adequate plan and schedule for meeting the Permit conditions; and, iv) DUSA has not caused pollution or potential for future pollution to Waters of the State under UCA S19-5-107. In a letter dated May 27,2011 DUSA provided notice to the Executive Secretary regarding Cell2 annual slimes drain compliance. In this letter DUSA Stated that, "Denison recommended that the monitoring requirement in the Permit be modified to allow the slimes drain pump sufficient running time to dewater the cell, and suggested as an example that the monitoring requirement could be reduced from monthly to quarterly." On June 30,2011, the Executive Secretary sent an email to DUSA with draft changes to the Ground Water Discharge Permit to change the slimes drain monitoring frequency from monthly to quarterly. This Permit modification was later executed by the Executive Secretary on July 14,2011. In a letter dated June l'7,2011, DUSA provided the DRC with a status update with a plan and schedule regarding Cell2 slimes drain compliance. In this letter, DUSA committed to the following three items: i. To regrade the interim cover fill on CellZby August l,2Oll; ii. That it has adjusted the slimes drain dewatering pump to cycle on for a longer time and at a narrower range of solution levels than before; and 3 H. L J. K. iii. That, "...Denison believes a reduction in the monitoring frequency under the cuffent pumping and monitoring regime will likely be sufficient to result in compliance with the Formula over time." L. After DRC review of the above mentioned DUSA submittals, the Executive Secretary concludes that DUSA failed to meet the affirmative defense provisions of the Permit as required by part LG.3(c) on at least one count because DUSA failed to provide a schedule for return to compliance with the Equation I requirements, i.e., re-establishment of a declining trend in the 3-year running average SDRE at Tailings CellZ' 6. DUSA agrees tol A. Come into compliance with the requirements of Part I.D.3.(bX3) and Equation I of the permit by re-establishing a declining 3-year running average SDRE trend at Tailings Cell 2 on or before December 31,2012, as determined by the Executive Secretary after DUSA submission of the Fourth Quarter, 2012 Routine DMT Performance Standards Monitoring Report (hereafter "Routine DMT PSM Report"), due on March 1,2013 pursuant to Part I.F.2 of the Permit, and B. Thereafter, maintain compliance with all requirements at the Tailings Cell2 slimes drain each and every calendar year for a minimum l0-year period. Each year DUSA's compliance *itt br determined by the Executive Secretary after review of the Fourth euarter Routine DMT PSM Report, for each calendar year. Pursuant to Part I.F.2 of the permit, the Routine DMT PSM Report is due on or before March 1 of the following year. DUSA agrces to pay stipulated penalty amounts for partial compliance or non compliance with this STIpULATED CONSENT AGREEMENT. If DUSA fails to comply or only partially complies with the terms in paragraph 6 of this STIPULATED CONSENT AGREEMENT, DUSA agrees to pay the stipulated amounts set forth below within 30 days of receipt of written request from the EXECUTIYE SECRETARY: A. If DUSA fails to come into compliance by the end of calendar year 2012, as required in Itern 6.A, DUSA agrees ro pay stipulated penalties in the amount of $1,000 per calendar day for every calendar day of non compliance in calendar yeat 2012; and B. If DUSA fails to maintain compliance for each calendar year between January 1, 2013 and December 31,2A22,as required in Item 6.8, DUSA agrees to pay stipulated penalties in the amount of $5,000 per calendar day for every calendar day after December 3l of each respective calendar year, i.e., 2013 thru 2022. DUSA agrees to pay any required penalties within 30 days of written notice from the EXECUTM SECRETARY, in the form of a check, made payable to the State of Utah, and delivered or mailed to: Division of Radiation Control Utah Department of Environmental Quality P.O. Box 144850 195 North 1950 West' Salt Lake City Utah, 84114-4850 g. The BOARD will view completion all of the requirements outlined in.this STIPULATED CONSENT AGREEMENT as compliance with the AGREEMENT. 7. 8. o 10. The deadline stipulated in items 6.A and/or 6.8 may be amended by prior written mutual agreement of the DUSA and the DRC ("Party"). The Party requesting the amendment must write to the other Party 30 days before the stipulated deadline and request an amendment of the deadline. The other Party will either agree to or deny the amendment in writing within 30 days. I 1 Nothing contained in this AGREEMENT shall preclude the BOARD from taking additional actions to include additional penalties against DUSA for permit violations not resolved by this AGREEMENT. l2.lf an agreement between DUSA and the EXECUTM SECRETARY cannot be reached in a dispute arising under any provision of this AGREEMENT, DUSA or the EXECUTM SECRETARY may commence an adjudicative proceeding in accordance with the Utah Environmental Quality Code, UCA l9-l-301 and the Utah Administrative Procedures Act to resolve the dispute. A final decision in any adjudicative proceeding shall be subject to judicial review under applicable state law. 13. Nothing in this AGREEMENT shall constitute a waiver by DUSA to raise in defense of any legal or factual contention for future allegations of noncompliance. 14. Nothing in this AGREEMENT shall constitute or be considered as a release from any claims, to include natural resource damage claims, cause of action, or demand in law or equity which the STATE may have against DUSA, or any other person, firm, partnership or corporation for any liability arising out of or relating in any way to the release of pollutants to waters of the State. 15. While the BOARD is presently not considering additional enforcement actions for any past or ongoing violations, nothing in this AGREEMENT shall preclude the BOARD from taking such actions to include other penalties against DUSA for violations of the ACT or permit violations not resolved by this AGREEMENT. DUSA AGREED to this day of David C. Frydenlund Vice President and Counsel Denison Mines (USA) Corp. 2011. UTAH WATBR QUALITY BOARD Rusty Lundberg Co-Executive Secretary By By F:\...\SCA Blackline final drft to Xmt l0-l l.doc --r-4- State of Utah GARY R. HERBERT Goverlor GREC BELL Lieutenant Governor Department of Environmental Quality Amanda Smith Execative Director DTVISION OF RADIATION CONTROL Rusty I-undberg Director lr*n., ( m,,ron )w?., fi3ffi0-20 1x_0tr'vg7 7 July 14, 2011 David C. Frydenlund Vice President and Counsel Denison.Mines (USA) Corp (DUSA) 1050 l Tth Street, Suite 950 Denver, CO 80265 Dear Mr. Frydenlund: SUBJECT:Ground Water Discharge Permit UGW370004 Permit Amendment The following are attached for your attention: I , a. Executed subject Ground Water Discharge Permit UGW370004 (Permit) Amendment, b. SiliiJ:llil;1ll'r*,orandum dated July 13,201r, ror the subject permit Amendment. c. Marked copy of the subject Permit Amendment indicating the changes from tlie previous Permit. This Permit change is a minor modification to the Permit. This Permit Amendment changes the monitoring requirements for the slimes drain recovery elevation testing from monthly to quarterly. The various changes to the permit are discussed in detail in item b. above. If you have questions on this Permit Amendment, please contact David Rupp ofmy staff. UTAH WATER QUALITY BOARD Ik-<l6uwao"7' Rusty Lundberg, Co-Executive Secretary DAR:dr Attachments F:\DUSA\GWDP\XmtlLtr 7-l 4-l l.doc 195 North I 950 West . Salt ,Jke City, I"rT Mailing Address: P O. Box 144850 'Sah take Ciry, UT 841 144850 Telephooe (80t) 536-4250. Fax (801) 5334097'T.D.D. (801) 5364414 wtuu'.deg.ilalLgor Printed on [00P./o rtrycle d paper rur!EoJ' r{[r'ruIT r;IEIEItf EI Eo.nrc ITEtEfr! David C Frydenlund Vice President & General Counsel Denison Mines (USA) CorP (DUSA) 1050 17th sT sTE 950 Denverco 80265 r Complete items 1, 2, and 3. Also complete item 4 it Restricted Delivery is desirsd.r Print your name and address on the reverse so that wo can return the card to you.r Attach this card to the back ot the mailpiece, or on the ftont lf space permits. DenverCO 80265 2. Artlcle Number David C Frydenlund Vice President & Generat Counsel Pgl.f .uines (usA) corp (ouinl 1050 17th sT sTE 950 I E Erpress Mall i E Betum Recddlot Merchandise : E c.o.D. l ,,ervico Typ€ E Cerrified Mall EJ Beglstereo El lnsured Mail 4. R€stdcted Ddverfi (EnE Fa)El ves ?0n1 lt6u 0001 lall, h67afr?Ensferfrorn servberab€, i Postsmil ii, iiiti; GWDP/perm't amendment / DR D. ls delivery add€ss dtfrer€nt from item 1? lf YES, enter delivery address below: PS Form 381 1, feOruary eOOa oomestic Retum Receipt rozss$oz-frr-r540 |l.-'-....llg.ulllllq9glPr I State of Utah GARY R. HERBERT Governor GREC BELL Lieutenant Governor TO: FROM: DATE: STIBJECT: Additional A. See attached markup of the current Permit,last modified on February 15,2011. This proposed markup is a monitoring change for the subject SDRE from monthly to quarterly lPart I.D.3(b), etc.l. This change was proposed by DUSA in three (3) submittals from DUSA dated February 25,May 27, and June 17, 2OIl. After review of the requested change in monitoring frequency, the DRC considers the proposed change to be a minor modification to the permit, and it is recommended we proceed with the change, as this action has the potential to l) increase the annual volume of slimes drain wastewater pumped from Cell 2, and 2) reduce the volume of wastewater stored in the Cell 2 tailings, that otherwise might have potential to leak to underlying soil and groundwater without this change. Department of Environmental Quality Amanda Smith Executive DireclLtr DTVISION OF RADIATION CONTROL Rusty Lundberg Director MEMORANDUM Rusty Lundberg Dave Rupp and Loren Morton July 13, 2011 / Statement of Basis for Minor Modification to DUSA Ground Water Discharge Permit (the Permit); Reduced Slimes Drain Recovery Elevation (SDRE) for Cell 2 Monitoring Frequency: Change of SDRE Testing to Quarterly Monitoring from Monthly Monitoring collateral changes were also made to the Permit, including: Parallel changes for Cells 3,4A and 48 slimes drain SDRE monitoring, as shown in various locations in the permit text. These are related to the following Permit sections: a. Consistent performance standards for Cells 4,A. and 4B [shown in Parts I.D.6(c) and I.D.13(c)1. b. Consistent monitoring requirements for Cells 2 and 3 [Part I.E.7(b)] and Cells 4,{ and 48 [Parts I.E.8(b) and I.E.l2(b)], c. Consistent reporting requirements for Cells 2 and 3 lPart I.F.1l]. Repoting requirements for Cells 4,A. and 48 will need to be added to the Permit at a future date when dewatering begins there. Change to the Cell2 Slimes Drain Performance Standard - The mathematics of 195 North 1950 West. Salt Lake City, UT Mailing Address: P.O. Box 1214850. Salt Lake City, UT 841l4-4850 Telephone (801) 536-4250. Fax (801) 5334W7 . T.D.D. (801) 5364414 www.deq.uloh.gov Printed on 1007o recycled paper B. Page 2 Equation I given in I.D.3(bX3) are changed to accommodate the new quarterly monitoring frequency. This formula is used to determine and compare the average head of three earlier years (years 2,3 and 4 years ago) in the slimes drain, to the average annual head of the three most current years (years 1,2, and 3 years ago). The purpose of this formula change is to equally weight the entries for new quarterly readings with the former monthly readings. Thus, the fewer quarterly readings will not be diminished in weight relative to the former monthly readings in calculation of annual average head. C. New compliance schedule item at Part I.H.7 to require DUSA to update / revise the DMT Monitoring and the Cell4,A. and 48 BAT O&M plans to reflect this change. The July ll,20ll effective date for use of quarterly monitoring [Part I.D.3(bX2)], and the August l,2Ol1 deadline for DUSA to submit the revised DMT and BAT monitoring plans [Part 1.H.7), were provided as a means of expediting implementation of the new monitoring frequency, and to encourage DUSA progress in de-watering the Cell2 tailings. Attachment: Changes to G.W.P. 01-14-ll SDRE Mos to Quarterly Monitoring.doc D. ,t r*o",.,* Govemor JON M GARY HERBERT Lieutenant Governor State of Utah Department of Environmental Quality Richard W. Sprott Executive Director Division of Radiation Control Dane L. Finerfrock Director April 10,2008 CERTIFIED MAIL (Return Receipt Requested) Mr. Steven D. Landau Manager, Environmental Affairs Denison Mines (USA) Corp. 1050 Seventeenth Street, Suite 950 Denver, CO 80265 Dear Mr. Landau: SUBJECT:2007 Fourth Quarter Discharge Minimization Technology (DMT) Performance Standard Monitoring Report for the White Mesa Uranium Mill. Cell2 Slimes Drain Monitoring: Confirmatory Action Letter with Comments and Recommendations We received the subject fourth quarter report on February 28,2008. As you will recall, effective March 17 , 2008, Part I.F.2 of the Ground Water Discharge Permit requires this report be submitted for Executive Secretary approval. However, at this time the report need not be approved. Comments; We have reviewed the subject report, and have the following comments: A). From the reported static water levels on the subject, we observe that there is a general trend for the water level to be rising in this slimes drain during 2007. We determined the average distance to water level reported for the year 2007 to be I1.29 feetbelow the access pipe measuring point, corresponding to a depth in pipe elevation above the slimes drain bottom of 26.7 | feet (38.00 - 11.29). This elevati on of 26.7 I feet will be used as the 2007 average elevation value in equation 1, found in Part I.D.3 of the current ground water discharge permit. This value will be incorporated into the permit at the next modification. B). We observed that on four (4) inconsecutive months (July, August, October, and November) of 2007 the cell 2 slimes drain pump was found to be not operating when the monthly inspectors arrived. No information was provided in the report regarding timing of pump repairs or the duration of pump breakdowns. I68 North 1950 West. PO Box 144850. Salt Lake City, UT 841 l4-4850. phone (801) 536-4250. fax (801) 533-4091 T.D.D. (801) 536-4414 . www.deq.utah.gov Mr. Steven D. Landau April 10,2008 Page2 As required by the Part I.D.3.b.I of the permit, "the Permittee shall at all times maintain the average wastewater head in the slimes drain access pipe to be as low as reasonably achievable in each tailings disposal cell, in accordance with a DMT Monitoring Plan. Compliance shall be achieved when the average annual wastewater recovery elevation in the slimes drain access pipe, determined pursuant to the currently approved DMT Monitoring Plan, meets the conditions in Equation 1 . . ." We acknowledge that compliance in this matter cannot be determined until after submittal of the 4ft Quarter, 2008 DMT Monitoring Report. Recommendation: In light of the above findings DUSA may need to make changes to the DMT Monitoring Plan and make other efforts to ensure future compliance with the requirement for declining annual average head in the Cell2 slimes drain. Confirmatory Action: However, the elevations of the slimes drain need to be expressed in terms of elevation above mean sea level. Therefore, the elevation of the water level measuring point on the slimes drain access pipe needs to be surveyed to establish its elevation. This elevation shall be certified in writing by a Utah Registered Land Surveyor or Professional Engineer. ln a conversation with you and Mr. David Rupp of this office on April4, 2008 you agreed to supply the above survey information in writing to DRC by the next quarterly DMT Performance Standard Monitoring Report due June 1, 2008. If you disagree with the above commitment and compliance schedule, please respond in writing within three (3) working days of receipt of this letter. UTAH RADIATION CONTROL BOARD, Dane Finerfrock Executive Secretary LBM:DAR:dr F:\dropp\DUSA\GWDPrelated docs\DMT\ 2007 4th Qtr 03-08 cmtltr.dm State of Utah Department of Environmental Quality Richard W. Sprott Executive Director DTVISION OF RADIATION CONTROL Dane L. Finerfrock Dire(tor TO: FROM: DATE: roN M rtr,ro*, r* Govetnor GARY HERBERT Lieutenant Governor File, DUSA Ground Water #1374 Dave Rupp, Environmental Engineer April4,2008 MEMORANDUM SUBJECT: Engineering Module 75A,2007 Fourth Quarter Discharge Minimization Technology (DMT) Performance Standard Monitoring Report for the White Mesa Uranium Mill dated Feb. 28, 2008. Confirmatory Action Letter with Comments dated April4, 2008; Critique on Cell2 Slimes Drain Dewatering Attached is a two-page spread sheet I created titled, DUSA Cell2 Slimes Drain Recovery Testing updated 3-6-08. On it there is a graph of the static or approximately static water levels of the slimes drain recovery testing since it began for Cell 2. Observe that the static water level shows a general trend to be rising in this slimes drain. The permit in effect at the time of this and earlier reports does not require approval of the report_s. Howiver, future reports will require approval per the current permit of March l7 ,2008. The 4ft Quarter 2007 rcport is not approvable, in that the slimes drain head in2007 shows a steady increasing trend (see attached chart). Consequently, if this trend continues this should be so stated in DRC cornment letters on quarterly reports. Report approval can only be attained by lowering the average annual head in the slimes drain as per Part I.F.11 of the permit. That cannot be determined until the first quarterly report in March 2009. The overriding goal on this subject is the performance standard of lowering of the ayerage annual head. This performance goal for DUSA must not be lost in pointing out specific problem issues, such as doing things to get better pumping efficiency. There are many avenues for DUSA to attain the overriding goal. We need not give them specific guidance, or even emphasize improvement items in inspections, which could form an excuse for non-compliance, should DUSA only comply with specific directives, and not take responsibility for reducing the head in the slimes drain. The following is a summary of some DRC pump efficiency related observations: l). On four (4) inconsecutive months (July, August, October and November), the pump was found to be not operating when the DUSA monthly inspectors arrived. Only attending to the pump site once per month seems problematic, and could leave month-long gaps in pump operation. DUSA inspectors should understand there is a recharge period between active operating times, and still 168 North 1950 West. P0 Box 144850. Salt Lake City, UT 841 l4-4850. phone (801) 536-4250. fax (801) 533'4091 T.D.D. (80 1 ) 536-441 4 . ww'w.de q.utah. gov z) 3). Memo on Module 75A March 27,2008 Page2 verify the pump is routinely turning on as required. They should be aware of monthly slimes drain level measurement. They should note when the pump is turned off for monthly water level recovery measurements. For other times if they find the pump is not operating, they should document it, and report to management. Documentation of timely repair of a malfunctioning pump couldbe an inspection item. E.g. per the provisions of Part IV.E (Duty to Provide Information) of the ground water discharge permit, we could get partial documentation by obtaining the Weekly Tailings Inspection Forms for the period of June I , 2007 through December 31, 2007 . The back page of the spread sheet shows more specific comments on the monthly readings. These were made by me, and the comments in italics by the DUSA inspectors, which measure the monthly slimes drain water levels. The allowed time in the DMT Monitoring Plan for restoring pump operation is l5-days after finding it not operating properly. Fifteen days to obtain parts and do repairs seems reasonable. However, multiple fifteen day repair periods separated only by short periods of operation seem unreasonable. There could be possible scenarios when a newly repaired pump might run for a few hours or days, then stop again. Such could result in long periods of down time. Under the existing plan, in the worst case, operating with a chronically inactive pump system problem could continue nearly indefinitely, as long as there is continual decrease in the average annual slimes drain water level (Permit LD.3). However, as the permit requires continued decrease in the annual average level, eventually efforts beyond using only the current pumping setup to lower the level will probably be needed. 4). DUSA may have had a short stint of bad luck with this pump system, or it simply should be upgraded before future breakdowns continue to occur (like an old car). To remedy or avoid chronic improper pump operation, it seems the DMT plan may need to be adjusted. (To eliminate chronic breakdowns, and eventually keep the water level lowering the company may elect to replace the entire pump system with new, unused equipment designed for the particular application, as endorsed by the manufacturer). Other means are available to improve pumping efficiency, including but not limited to changes in the following:(a). Pump control systems, i.e. replace the current clock timer with a water level based controller.(b). Pump size or capacity. i.e. use a smaller pump that runs for more hours per year, etc. We could strain at the issue of chronic improper operation, but eventually the company will have to come to grips with the reality, that they must make improvements to attain the DMT standard of lowering the water levels annually. However, we should encourage DUSA to make improvements, but reminding them of the end goal of meeting the annual average water level reduction requirement, as defined in the current permit dated March 17,2008. Attachment: DUSA Cell2 Slimes Drain Recovery Testing two-page spread sheet. F:\drupp\DUSA\GWDPrelated docs\DMT\N,lem on 2007 4th Quarter Rpt 03-08.doc o T1'e #Wcnhd e{-pr Aa)"& t4 (u\7 zot\ {o*nJ b. ^t 9BC */,atl- AV7077 (-',,r?yl X4^rt LL,*") State of Utah GARY R. HERBERT Governor GREG BELL I-ieutenant Governor TO: FROM: DATE: SUBJECT: Department of Environmental Quality Amanda Smith Executive Director DIVISION OF RADTATION CONTROL Rusty Lundberg Director MEMORANDUM Rusty Lundberg and Loren Morton DaveRupp fur-, May 3,2011 Decision Paper for Possible NOV DUSA Exceedance of Ground Water Discharge Permit Elevation Requirements for Dewatering of Tailings Cell No. 2; Fourth Quarter, 2010 DMT Monitoring Report Summary: The DUSA Ground Water Discharge Permit requires that the below ground, stabilized phreatic water surface elevation in tailings Cell2 drop when compared to the previous average years, as defined by a formula found in the permit. In the year 2010, this stabilized phreatic surface rose 0.09 feet (1.0S-inches) compared to previous years. This violates the permit requirements. This MEMO discusses the background of the dewatering requirements. Some verbiage is also quoted. Quoted verbiage of significance is underlined and is in blue below for emphasis. It appears we have a positive position for issuing an NOV for this result. However, DUSA appears to have a weaker argument, based on the fact that we have created this problem by being prescriptive with monitoring requirements for Cell 2 dewatering efforts. Please let me know if you have questions or wish to proceed or not to issuance of an NOV regarding their unsuccessful dewatering of Cell2. I.Esslsd: Historically, beginning in2007, DRC has attempted to write Permit requirements on this subject to be non- prescriptive. This was to allow DUSA freedom to take whatever actions they deem necessary to meet the requirement. The permit requirement is to keep reducing the annual average slimes drain recovery elevation (SDRE) below the arurual average SDRE of the previous year, which is defined as being ALARA. In the subject 2010 4m Quarter report, DUSA states a position that the DRC monitoring requirements are prescriptive, and it interferes with the dewatering of the tailings cell. As a result of the prescriptive nature of the monitoring, coupled with unusually wet weather, DUSA is unable to meet the permit requirements, and thus the current annual average SDRE is above the annual average SDRE ofa year ago. II. hrguments. f indinss. and References: A. ALARA Argument: The monitoring method to determine the SDRE is prescriptive. It is defined in the DMT Plan. However, the DMT Plan and Permit attempt to be silent with respect to methods to 195 North 1950 West . Salt lake City, UT Mailing Address: P.O. Box 144850 . Salt Inke City, UT 84114-4850 Telephone (801) 5364250. Fax (801) 5334097 ' T.D.D. (801) 5364414 ww.deq.utah.gov Printed on 100% recycled paper Page2 attain compliance. 1. E.g. some possible methods, in addition to the status quo are: Covering the tailings surface with some type of liner system to divert storm water and reduce infiltration, and thus the SDRE. Installing an orgarized vegetative cover to increase transpiration and thus reduce the SDRE. Use of an additional well point(s), pu-p(s), and piezometers to reduce the SDRE. Adjustment of the pump specifications to be more efficient, and increase the annual volume of discharge, and thus reduce the SDRE . Other innovative methods. In the approved DMT Plan, DUSA makes a statement that, "Mill manaeement con averaee allowable wastewater head in the Cell 2 slimes drain resulting from pumping in this manner is satisfactory and is as low as reasonably achievable." Although the DMT Plan was approved by DRC, DRC only accepts this statement at face value, i.e., that Mill management considers the configuration as ALARA. DUSA argues in the subject 20rc 4h Quarter report, the following pertaining to prescriptive requirements: "...for the reasons discussed below, Denison believes that the monitoring requirements of Part LD.3(.b X2) seriously interfere with Denison's ability to comply with Parts I.D.3(bXi) and I.D.3 &X3) and should be amended." "Part LD.3(b)(2) of the Permit requires that each slimes drain monthly monitoring test: 1) includes a duration of at least 9O-hours, as measured from the time that pumping ceases, and2) achieves a stable water level at the end of the test, as measured by three consecutive hourly water level depth measurements, with no change in water level, as measured to the nearest 0.01 foot. "It should be noted that. in 2010. order to meet the test requirements: "1. The slimes drain pump has remained off an averase of 6.42 days per month every month for performance of the measurements. and "2. This means that the slimes drain pump remains off approximatelv 77 days (11 weeks) per vear or 20 percent of the vear for performance of measurements. "That is. in order to meet the reouirements for testins in Part I.D.3(b)(2) of the Permit. it has not been possible to run the slimes drain pump often enoush to meet the requirement in Part I.D.3(bX1) of the Permit that Denison maintain the averase wastewater recovery head in the slimes drain access pipe as low as reasonably achievable. when the pump can only be run 80o% of the time. That is. the monitorins requirement to demonstrate the slimes drain level has been reduced. seriously interferes with the pumping needed to reduce the slimes drain level. "Nonetheless. even with the limitation of qperatine only 800/0 of the year due to the monitoring constraint. the Mill has maintained the slimes drain at an approximately constant level. It is anticipated that if the monitorine constraint were modified to allow more pumpine time. compliance with the Part I.D.3(b) requirements could be achieved. Denison recommends that the monitorine requirement in the Permit be modified to allow the slimes drain prmp sufficient a. b. c. d. e. 2. 3. Page 3 runnins time to dewater the cell. For example. the monitorins requirement could be reduced "In addition, the following factors should be noted: " 1 . The slimes drain elevation measured at the end of 2010 was lower than the slimes drain elevation measured at the beginning of 2009, indicating an overall reduction in elevation; "2.For both 2009 and 2010 there appeared to be a rise in elevation over the period from January through March, followed by a reduction over the remainder of the year. The rate of reduction for the remainder of the year in 2010 was lower than in 2009, possibly due to the significantly higher precipitation experienced in 2010 of 15.13 inches compared to the 2009 total precipitation of 8.13 inches. The Mill was able to maintain the 2010 slimes drain recovery level within 1 inch of the preceding year's level despite the fact that the annual precipitation was 7 inches (186%) higher than the preceding year." B. Duration Period of Interest: All SDRE data collected from 2006-2008 was deemed unacceptable to DRC and has not been used. For the subject 2OlO 4t'Quarter report, the period of interest is data from 2009 and 2010. C. Documents of Interest l.Ground Water Discharse Permit. Since the August 26,2009 DRC review letter regarding of the first quarter 2009 DMT Monitoring Report (reference 1 below), DRC review of these quarterly reports has stated that, "As you are aware as required by the Part I.D.3.b.1 of the permit, 'the Permittee shall at all times maintain the average wastewater head in the slimes drain access pipe to be as low as reasonably achievable in each tailinss disposal cell. in accordance with a DMT Monitorine Plan. Compliance shall be achieved when the averase annual wastewater recovery elevation in the slimes drain access pipe. determined pursuant to the currentlv approved DMT Monitoring Plan. meets the conditions in Equation l . .'We note ' that pursuant to Part I.D.3(b) of the upcoming Ground Water Discharge Permit modification, that Cell 2 compliance in this matter will be determined after submittal of the 4ft Quarter, 2010 DMT Monitoring Report." Wite Mesa Mill Tailings Management System; and Discharge Minimization Technologt @MD Monitoring Plan IDMT Planl, 01/1 1 Revision: Denison- 11.1. Documentum No. DRC-2011-001089. The latest plan was approved on January 20,2011. It requires the following, with some verbiage underlined and in blue for emphasis: a. Section 3.1.b, ".. .Slimes Drain Water Level Monitoring. .. "(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 2. ' OUSR appears to now believe that the existing conf,rguration is not ALARA, as they had earlier written that it was. Page 4 at five feet above the bottom of the slimes drain standpipe. The average wastewater head in the Cell 2 slimes drain fstandpipe] is therefore less than 5 feet and is below the phreatic surface of tailings Cell2, 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 Cell2 into the slimes drain collection system. Mill manaeement considers that the averaee allowable wastewater head in the Cell 2 slimes drain resulting from pumpine in this manner is satisfactory and is as low as reasonabl], achievable. .." .. .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 chanqe 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 measurine the depth to water below the water level measurins point on the slimes drain access pipe... "(vii). No process liquids shall be allowed to be discharged into Cell2; "(viii)- If at anv time the most recent averase 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 complv with the requirements of Part I.G.3 of the GWDP. includins the requirement to provide notification to the Executive Secretary orally within 24 b. DMT Plan. Section 8.2.e "An annual summary and graph for each calendar year of the depth to wastewater in the Cell2 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." Chronolosical References : 1. February 25,2071 the subject Wite Mesa Mill Discharge Minimization Technologt @Mf) Pedormance Standard Monitoring Report (DMT Report), and Cell 4A BAT Performance Standards Monitoring Report (Cell 4A BAT Report) for the 4ft Quarter, 2010, submitted as a single volume. DRC-201 l-002214. 2. June 30, 2010 Ground Water Discharge Permit Part I.D.1.b.4, regarding CellZ, states, a. "...At cell closure. leachate head inside the pipe network will be removed via a submersible pump installed inside the 24-inch diameter HDPE access pipe." b. Part I.D.3.b(l) states, "slimes Drain Maximum Allowable Head - the Permittee shall at all times maintain the averase wastewater head in the slimes drain access pipe to be as low as reasonabllr achievable in each tailinss disposal cell. in accordance with a DMT Monitoring Plan." c. Part LD.3.b.3 also states, "Annual Slimes Drain Compliance - shall be achieved when the average annual wastewater recovery elevation in the slimes drain access pipe, as determined pursuant to the currently approved DMT Monitoring Plan, meets the conditions in Equation 1..." 3. April 7, 2009 DRC Notice of Non-Compliance letter states, "DUSA must become more pro-active in providing intemal QA control in areas of both test performance and report preparation. Further, "(vi). Page 5 we encourase DUSA to come to DRC with revisions to the DMT Plan. or other plan required by the Permit. immediately after a problem is identified." 4. April 10, 2008 DRC Confirmatory Action Letterwith Comments and Recommendations. This letter states that: "From the reported static water levels on the subject, we observe that there is a general trend for the water level to be rising in this slimes drain during 2007." "We obseryed that on four (4) inconsecutive months (July, August, October, and Novernber) of 2007 the cell2 slimes drain pump was found to be not operating when the monthly inspectors arrived. " "ln lieht of the above findings DUSA may need to make changes to the DMT Monitoring Plan and make other efforts to ensure future comoliance with the requkement for declining annual averase head in the Cell 2 slimes drain." 5. October 4,2007,GroundWater Quality Discharge Permit, Statement of Basis, p.7 states: a. "...During review of the DMT Monitoring Plan for Cells 1, 2, and 3, the Executive Secretary determined it necessary to impose certain operational, monitoring, and reporting requirements. The purpose of these new requirements is to: 1) accelerate the dewatering of the tailing cells during post operations, and 2) mirrtmize the accumulation and storage of fluids and contaminants in the tailing cells, in order to protect public health, and the environment, and local ground water resources. To this end, a new performance standard was added to Part I.D.3(bX1) to require that compliance at the Cell 2 and3 slimes drain is defined as continuously declining waste water head, as determined on an annual average basis. Conversely, an increase in the annual average slimes head, over that of the previous year will be considered non-compliant with the Permit." "To standardize slimes drain monitoring at cells 2 and 3, additional requirements were added to Part I.E.6(b). These changes include monitoring in accordance with the currently approved DMT Monitoring Plan, which in tum calls for a monthly slimes drain recovery head test of90 hours. "To ensure the monthly and annual average slimes drain head data is provided to the Executive Secretary for approval, a new requirement was added atPart I.F.1 1. In the event that the average annual slimes drain recoverv head for a given year is greater than the previous ]uear [see Part I.D.3(a)] and the Executive Secretary may take enforcement action to re-establish DMT at Cells 2 and 3. "The Permittee is required to: 1) measure individual monthly slimes drain recover head .monitoring data [as required in Part I.E.6(b)], 2) calculate the average slimes drain recovery head and, 3) demonstrate compliance status with the requirements of Part I.D.3 and 6 of this Permit for Tailing Cells 3 and 3. This section of the Permit was added to require the Permittee to submit an annual slimes drain recovery head report for Tailing Cells 2 and 3 to summarize the above data." DUSA l't Quarter DMT Monitoring report dated June 1,2009. This is the frst report which established the new basis for the average annual SDRE for 2009. May 9, 2007 DRC Letter regarding the DMT Plan states, "2. Regardine Cell2. A.)The DMT plan and the cover letter express that there is no need to consider other types of pumpins svstems. as the reduction of the static head in Cell 2 is not a function of the speed a. b. b. d. 6. 7. Page 6 of pumpine out of the slimes drain access pipe and there are no oractical altematives. However. no justification for these claims was provided." "B.) Apart from pumpins. it is important to note that the depth of static head on the Cell 2 liner can be reduced blz methods such as coverins the tailines. improvine transpiration" etc.. to meet the DMT performance standards (Ground Water Discharse Permit I.D.3.b). "C.) Attainins minimum head on the Cell 2 liner is a major step to closure of the cell." 8. January 24,2007 DRC Letter, regarding a draft DMT Plan states, "Regardiqq the wastewater head on the liner in Cell 2... the Permit requires the permittee to determine an averaee allowable head that is as low as reasonablv achievable (ALARA). The existinq pumping system has been functioning there for a long time. If there have been no process inflows. the head mav have been stabilized to a static level by that same pumping system. However. the head could also be increasing or decreasins. The monthly chanses in the head are unknown. because no historic head monitorins has been done." "Paraeraoh 3.1.b.iii of the current DMT plan mentions that mill manasement considers that the head in Cell 2 from the existing pumpinq system is ALARA. However. no justification for this claim was provided. As noted above. the head in the cell may have been stabilized by the existing pumpins slustem. but it malz not be ALARA. This is because more efficient pumpinq systems mav be available to lower the head even firrther. "Please provide additional information and justification to show the existing pumping system equipment and operation provides both a cost effective and maximum annual wastewater removal. Conversely, if there are other pumping systems that can produce a maximum annual removal of wastewater in a cost effective manner, please identiff and describe them." The following appears to be verv important: "To veriflr that the existins pumping system is ALARA will require two demonstrations. as follows: a. Maximum and Cost Effective Removal of Wastewater. as mentioned above. and b. A Declinine or Static Wastewater Head - Evidence must be provided that the slimes drain wastewater head in Cell 2 is declinine or static. The static head case is appropriate in the event that the above cost effective and maximum pumpins case is made and accepted. Conversely. an increasine wastewater head in Cell 2 is not ALARA. and is not acceptable to the DRC." "...Therefore, the DMT Plan needs to include the following: ... c. A performance standard such that if at any time the most recent averase annual head is found to have increased above the average head for the previous calendar year. Denison Mines will comply with the DMT Failure requirements of Part I.G.3 of the Permit (includins but not limited to reportine and corrective actions)." 9. September 26,2006 DRC Letter, regarding a draft DMT Plan states, "The DMT plan needs to include a method to measure the static head above the liner in Cell No. 2 as part of the performance criteria for the Ground Water Discharge Permit...By measuring the o static water level in the tailines. IUC will be able to show if the drop in head is beine optimized by the pumpinq technique beins used." PageT "Potential options to measure the static head above the liner include installing a piezometer near the slimes drain access pipe. or shuttins of the pump and measuring the water level after static equilibrium has been reached (i.e. a head recovery test)... "As a future reference, the Ground Water Discharge Permit will need to be modified to include a decline of the static water levels in the tailings as a performance criterion..." Other Minor Miscellaneous Observations reeardine the 2010 4ft Ouarter DMT Report: L LDS inspections for the New Decontamination Pad (NDP) Sedimentation Tank at the mill are recordedinthesubjectreportfortheperiod of 4l2ll0 through 6125110. Theseinspections occurred; although the NDP was not in use after a DRC Cease and Desist order regarding use of this pad was issued on May 13,2010. DRC authorized use of the NDP on February 7,2011. II. The report in paragraph 3.0 as well as Attachment A shows that numerous freeboard exceedances for Cell 3 occurred during the 4ft Quarter of 2010. Freeboard exceedances for tailings Cell 3 were not resolved during this reporting period, but were resolved in the next quhrter per DRC letter dated March 14,2011. IIL Paragraph 7.0 of the report discusses liner repairs are underway for the Cell I liner, as a result of discovery of leakage in the Cell 1 LDS on June 2, 2010 and later on August 7 , 2010. As approved in a DRC Confirmatory Action Letter (CAL) dated September 22,2010, DUSA has committed to complete repair of these leaks by July 3 1 , 2012, and submittal of the required repair report by December 1,2072. -END- F:\GWDP RelDocs\DMT&BAT Reports\2010\l\,IEMO on Slimes Dewatering 5-201 l.doc State of Utah GARY R. HERBERT Govemor GREG BELL Lieutenant Govemor Department of Environmental Quality Amanda Smith Exerutive Director DIVISION OF RADIATION CONTROL Rusty Lundberg Director January 20,2OIl CERTIFIED MAIL (Return Receipt Requested) Ms. Jo Ann Tischler Director, Compliance and Permitting Denison Mines (USA) Corp (DUSA) 1050 17u'Street, Suite 950 Denver, CO 80265 Dear Ms. Tischler: SUBJECT:January 10, 2011 DUSA Letter, Transmits Revised DMT and BAT O&M Plans, which addresses White Mesa Uranium Mill Tailings Cell 4B, etc.; January 6,2011 DRC Letter, Review of Revised DMT and BAT O&M Plans; Contingent Approval of the Proposed DMT Plan We have reviewed the subject letter from DUSA dated January 10, 2011, which is a response to the subject DRC comment letter of January 6,2011. The DUSA letter proposes the two subject documents, noted above. However, this letter only addresses the proposed DMT Plan, as revised, known as The White Mesa Mill Tailings Management System and Discharge Minimization Technology (DMT) Monitoring Plan (DMT Plan), 0l/11 Revision: Denison-11.1. After review of this plan, we have no further cornments. Therefore, the DMT PIan as titled immediately above, is approved, contingent upon DUSA receiving written DRC authorization to use CelI4B. UTAH RADIATION CONTROL BOARD Rusty Lundberg, Executive Secretary DAR: dr Cc:Harold R. Roberts, DUSA Phillip Goble, DRC F:\DUSA\ CWDPermiI\DMT PIan History\DMT Plan ContApproval 0l -20-201 I .doc 195 North 1950 West. Salt t-ake City, UT Mailing Address: P.0. Box 144850. Salt hke City. UT 841 14-4850 Telephone (801 ) 536-4250. Fax (801) 533-4U)7 . T.D D. (801) 536-4414 www.tleq.utah.gov Printed on 100% recycled paper State of Utah Department of Environmental Quality Richard W. Sprott Executive Director DIVISION OF RADIATION CONTROL Dane L. Finerfrock Dire(lor TO: FROM: DATE: oJON M. HLINTSMAN. JR. Govemor GARY HERBERT Lieutenant Covernor File, DUSA Ground Water #137 A Dave Rupp, Environmental Engineer February 7 ,2008 MEMORANDUM SUBJECTz 2007 First, Second and Third Quarter Discharge Minimization Technology (DMT) Performance Standard Monitoring Reports for the White Mesa Uranium Mill. Notice of Enforcement Discretion: Quarterly Reporting of Cell2 Omission of Monthly Slimes Drain Recovery Test Results and Readings A letter, subject as above dated February 7,2008, discusses the details of omission of all of the slimes drain test results and readings from the first three quarterly reports of 7007 . Attached to this memo is the email data supplied by DUSA via an email on October 31,2007. Also attached is a spread sheet titled DUSA Cell2 Slimes Drain Recovery Testing. Included on this spread sheet is a graph of the end point of the static or approximately static water levels of the slimes drain recovery testing for Cell 2. Note that the recovered slimes drain surface graph shows an overall increasing pattern at this time. The difference of barometric pressure from the mill to the tailings cell should not be significant. Also, at most, only one reading of barometric pressure was recorded per day on the submitted data. The DUSA DMT monitoring plan requires the recovery test to be at least 90 hours. This was not always followed, if the water level was found to be static for a period of time. Attachments: l. submitted data by DUSA (oct. 31, 2007). 2. DUSA Cell 2 Slimes Drain Recovery Testing spread sheet. F:\drupp\DUSA\CWDhelated docs\DMT\Memo on 2007 I sr3rd Quarter Rpts 02-08 168 North 1950 West . PO Box 144850 . Salt Lake City, UT 841 14-4850 . phone (801) 536-4250 . fax (801) 533-4097 T.D.D. (801) 536-4414 . www.deq.utah.gov DBc'Joll'oo ?ztt1I I I I I I I I I I I I I I I I I t I DEN,ronDll MINES February 25,2011 Sent VIA Federal Express Mr. Rusty Lundberg Co-Executive Secretary Utah Water Quality Board Utah Department of Environmental Quality 195 North 1950 West P.O. Box 144810 Salt Lake city, UT 84114-4820 Re: Transmittat of DMT Performance Standards Monitoring Report and Cell 4A BAT Performance Standards Monitoring Report for the 4th Quarter of 2010 Dear Mr. Lundberg: Enclosed please find two copies of the DMT Performance Standards Monitoring Report and Cell 4A BAT Performance Standards Monitoring Report for the 4s Quarter of 2010, as required under Parts I.F.2 and I.F.3 of the White Mesa Mill's State of Utah Groundwater Discharge Permit No. UGW370004. Also enclosed are two CDs, each with an electronic word-searchable copy of the enclosed Report. If you have any questions regarding this Report, please contact the undersigned at (303) 389- 4132 or Mr. David Turk at (435) 678-2221. Yours very truly,Ofr*fu / DnNrsox MrxBs (USA) Conp. Jo Ann Tischler Director, Compliance and Permitting cc David C. Frydenlund Ron F. Hochstein Harold R. Roberts David E. Turk Kathy Weinel Denison Mines (USA) Corp. 1050 17th Strset Suite 950 Denver, CO 80265 USA Tel : 303 628-7798 Fax : 303 389.4125 www.denisonmines.com I t WHITE MESA URANIUM MILL DMT PERFORMANCE STANDARDS MONITORING REPORT AND CELL 4A BAT PERFORMANCE STANDARDS MONITORING REPORT 4th Quarter October through December 2010 State of Utah Groundwater Discharge Permit No. UGW370004 Prepared By: Denison Mines (USA) Corp. 1050 lTth Street, Suite 950 Denver, CO. 80265 February 25,2011 1.0 2.0 I I I I I I I t I I I I I I I I I I I 3.0 4.0 4.1 4.2 4.3 4.4 5.0 6.0 TABLE OF CONTENTS INTRODUCTION MEASUREMENTS TAKEN AND MONITORING PERFORMED DURING THE QUARTER.............. ...................1 WEEKLY TAILINGS WASTEWATER POOL ELEVATION MONITORING ......2 MONTHLY SLIMES DRAIN WATER LEVEL MONITORING Rrsulrs FoR THE Quanren.. ..........................4 Quelrrv AssuReuce EvaluarroN AND Dere VelmertoN .........4 Gnepnrc CoupenrsoN ro PRsvrous Yra.R.... .................5 WEEKLY WASTEWATER LEVEL MONITORING: ROBERTS POND................5 WEEKLY FEEDSTOCK STORAGE AREA INSPECTIONS AND INSPECTIONS OF FEEDSTOCK MATERIAL STORED OUTSIDE THE FEEDSTOCK STORAGE AREA ......................5 7.0 TAILINGS CELLS AND POND LINER SYSTEM REPAIRS ..................5 8.0 DECONTAMINATION PADS..,.........6 8.1 SuuuaRy or WepKLy WersR LBver. (DeerH) INspecrroNs.................. ...........6 8.2 Alwuel INspecrroN or Exsrrxc DecoNreMrNATroN Peo............ ....................8 8.3 Npw DgcoNTAMTNATToN Pen........ ................8 9.0 CELL 4A BAT PERFORMANCE STAI\DARDS REPORT FOR THE QUARTER............8 9.1 LDS MoNrroRrNG...... ...................8 9.1.1 Operational Status of LDS Pumping and Monitoring Equipment ..............8 9.1.2 Measurement of Weekly Fluid Headatthe Lowest Point inthe Secondary Membrane...........9 9.1.3 Measurement of the Volume of Fluids Pumpedfrom the LD9.......... ..........9 9.2 MsasuRpvtENT oF Wpxr,y Wasrewernn Flurps n r CrLL 44.............. ...........9 9.3 Sr-rvrps DnerN Rrcoveny Hnep MoNrroRnqc................. ..................9 1O.O ANINUAL SLIMES DRAIN RECOVERY HEAD REPORT FOR THE CALENDAR YEAR 2O1O 10.1 INprvtpuel Slnars DReru Recovsny Hrep ron 2009.. ............... l0 10.2 AveRnce SLrN,tes DnerN RBcovsRy Heeo ron 2010.. ................... l0 10.3 TrMr SBRrss CHARr.... ................10 i N:\Required Reports\DMT Reports\2010 DMT Report\q4 2010 DMT Report\q+ 2010 DMT RepOrt dfaft.dOCX 15 A B C D E F G I I I I I I I I I I I I I I I I I I I 10.4 Quelrrv AssuneNce EvnluerloN AND Dere ValIoattoN .......10 10.5 DekroNsrRArroN oF CouplreNcs Srerus wrrH rHE RseuInsMENrs oF eenr I.D.3(e) exo I.E.7(e) or rur Penvn .........................11 10.5.1 Permit Requiremenls................ ...............11 10.5.2 Demonstration of Compliance with Permit Requiremenls................ ...............12 11.0 SIGNATURE AND CERTIF'ICATION LIST OF TABLES Table I - Summary of Waste Water Pool Elevations Table 2 -New Decontamination Pad Inspection Portal Level for the Second Quarter 2010 Table 3 - SDRE Data to be Used for Certain Years Table 4 - Cell2 Slimes Drain Recovery Head and SDRE Values for 2010 Table 5 - Cell 2 Slimes Drain Recovery Head and SDRE Values for 2009 ATTACHMENTS Tailings Cell and Roberts Pond Wastewater Elevations Notices Pursuant to Part I.G.3 of the Permit Monthly Cell2 Slimes Drain Monitoring Data for 2010 Graph of Cell2 Slimes Drain Water Levels Over Time Cell Liner Repair Reports and Notices Cell 4,A. Leak Detection System Data for the Quarter and BAT O&M Plan Table 1A Annual Inspection Forms for Existing and New Decontamination Pads (Part I.F.12) a a a 1.0 I I I I I I t I I I I I I I I t I I I WHITE MESA URANIUM MILL DMT PERFORMANCE STANDARDS MONITORING REPORT AND CELL 4A BAT PERFORMANCE STANDARDS MONITORING REPORT FoR THE 4'h qUARTER oF 2o1o TNTRODUCTION This is the routine Discharge Minimization Technology ("DMT") Performance Standards Monitoring Report for the 4th quarter of 2010 (the "Quarter") prepared by Denison Mines (USA) Corp. ("Denison"), as required under Part I.F.2 of the White Mesa Mill's (the "Mill's") State of Utah Groundwater Discharge Permit No. UGW370004 (the "Permit"), and the Routine Cell 4,{ Best Available Technology ("BAT") Performance Standards Monitoring Report for the Quarter, as required under Part I.F.3 of the Permit. 2.0 MEASUREMENTS TAKEN AND MONITORING PERFORMED DURING THE QUARTER During the Quarter, the following DMT monitoring was performed or addressed, as required under Part I.D.3, I.8.7, and I.F.11 of the Permit: Weekly tailings wastewater pool elevations for tailings Cells I and 3 (Part I.E.7(a)); Monthly slimes drain water levels in Cell 2 (Part I.D.3(b)(1) and (2)); Annual Slimes Drain Compliance (Part I.D.3 (b) and LF.l1 Weekly wastewater level measurements in Roberts Pond (Part I.D.3(e) and Part I.E.7(a)); Weekly feedstock storage area inspections and inspections of feedstock materials stored outside of the feedstock storage area (Part I.D.3(f) and Parts I.E.7(d) and (e)); Any tailings cell and pond liner system repairs (Part I.E.7 (0 and Part I.E.(8)(c)); Weekly New Decontaminatin Pad Inspection (Part I.E.7 (g)) and Annual Decontamination Pad Concrete Inspection (Part I.F.l1) (not required this reporting period) Also during the Quarter, the following Cell 4A BAT performance standards monitoring was performed or addressed, as required by Parts I.E.8 and I.E.lz of the Permit: o Leak detection system ("LDS") monitoring for Cell4A (Part I.E.8.(a)); and o Weekly tailings wastewater pool elevations for tailings Cell4,A. (Part I.E.8 (a)). L N:\Required Reports\DMT Reports\2010 DMT Report\Q4 2010 DMT Report\Q4 2010 DMT Report draft'dOCx a o a I I I I I I I t I I I I I 3.0 WEEKLY TAILINGS WASTEWATER POOL ELEVATION MONITORING Mill personnel monitored and recorded weekly the elevation of wastewater in Tailings Cells l, 3 and 4,{ to ensure compliance with the maximum wastewater elevation criteria mandated by Condition 10.3 of the Mill's State of Utah Radioactive Materials License No. UT 1900479 (the "License"). These measurements were made from an elevation survey. The results of such monitoring, reported as feet above mean sea level (fmsl), are included in Attachment A. Condition 10.3 of the License provides that the freeboard limit for Cell 1 shall be set in accordance with procedures that have been approved by the U.S. Nuclear Regulatory Commission ("NRC"). Under those procedures the freeboard limit for Cell I is set as per the January 10, 1990 Drainage Report for Cell 1 at a liquid maximum elevation of 5,615.4 fmsl. Condition 10.3 of the License also provides that the freeboard limit for Cells 3, 44 and 48 shall be recalculated annually in accordance with the procedures approved by the Executive Secretary of the State of Utah Radiation Control Board (the "Executive Secretary"). The current freeboard limit for Cell 3 was previously calculated under this procedure at 5,601.6 fmsl. However, in a letter from the Executive Secretary dated November 20,2008, an interim variance and limit was established at 5,602.5 fmsl for Cell 3. The Mill has filled Cell 3 to its final tailings solids capacity in preparation for closure, and pre- closure activities are underway. As discussed in the DMT Performance Standards Monitoring Report and Cell4A BAT Performance Standards Monitoring Report for the 3'd Quarter of 2010, the process of filling Cell 3 with solids and the reduction of the liquid "pool" area to a number of small "puddles" has rendered the freeboard limit meaningless. The solids filling activities in the third quarter of 2010 resulted in two apparent exceedances of the freeboard limit, which were the subject of a Notice to the Executive Secretary under Part I.G.3 of the Permit and Utah Administrative Code ("UAC") R3l7-6-6.16(C), dated August 4,2010. The notice of August 4, 2010 explained that it is no longer possible to manage the Cell 3 freeboard to achieve the calculated freeboard limit during the final stages of filling Cell 3 with solids and closing Cell 3. The continuing solids filling process during the fourth quarter of 2010 resulted in all but one of the weekly fluid elevation measurements remaining above the freeboard limit of 5,602.50 fmsl as anticipated in the notice of August 4,2010. However, as discussed below, at no time has the fluid level exceeded the maximum wastewater elevation of 5605.5 fmsl as required under Part I.D.2 of the Permit. In addition, Part I.D.2 of the Permit provides that under no circumstances shall the freeboard of any tailings cell be less than three feet, as measured from the top of the flexible membrane liner ("FML"). The top of the FML in Cell 1 is at 5,618.5 fmsl, the top of the FML in Cell 3 is at 5,608.5 fmsl and the top of the FML in Cell 4A is at 5,598.5 fmsl. This means that the maximum wastewater pool elevations in Cells 1, 3 and 4,A, permitted under Part 1.D.2 of the Permit are 5,615.5, 5,605.5 and 5,595.5 fmsl, respectively. The wastewater pool elevations in Cells l, 3 and 44, as measured during the Quarter, are summarized in the following Table 1. As indicated in Table l, the applicable freeboard limits 2 N:\Required Reports\DMT ReportsUOl0 DMT Report\Q4 2010 DMT Report\Q4 2010 DMT Report draft.dOCX I I I t I I I I were not exceeded during the Quarter for Cell 1 and Cell 4,A'. As discussed above, Cell 3 is currently filled with solids and the freeboard limits are no longer meaningful. I I Table I - Summary of Waste Water Pool Elevations I I I I *This is the maximum wastewater elevation in Cell 3 during the Quarter.** Cell 3 is now full of solids, is undergoing pre-closure steps, and the freeboard limit specified here is no longer meaningful.**r' The freeboard limit for Cell 4A is not set out in the License. The freeboard limit of 5,593.74 for Cell 4A is set out in a letter from the Executive Secretary dated November 20,2008. Denison proposed in the DMT Plan revision dated November 12, 2010 the removal of the freeboard limit for Cell 4A' to be replaced by a freeboard limit for new Cell 48 that will accommodate the freeboard requirements of Cells 2, 3, 4A, and 48. The Executive Secretary granted a variance from the Cell 44 freeboard limit on January 13,20ll and approved the removal of the Cell 4A limit and the use of Cell 4B on January 27 ,2011 . It should be noted that the maximum elevation of 5,593.74 fmsl for Cell 4,{ has been set assuming that the total probable maximum precipitation ("PMP") volume for Cells 2,3 and 4A will be accommodated in Cell 4A. By letter dated December 11, 2008, Denison applied for an amendment to the License to set the freeboard limit for Cell 4A at 5,593.74 fmsl and to eliminate the need to set a freeboard limit for Cell 3, given that the freeboard limit of 5,593.74 fmsl for Cell 44 is adequate to accommodate the total PMP volume for Cells 2,3 and 4A. The Utah Division of Radiation Control ("DRC") has indicated, in a letter of April 29, 2010, their agreement with Denison's proposed revisions to the freeboard limits for Cells 3 and 4.{, pending Denison's submittal of revisions to the Permit and the W'hite Mesa Mill Tailings Management System and Discharge Minimization Technologt Monitoring Plan ("DMT Plan") reflecting the proposed changes. Denison prepared and submitted these revisions on November 12,2010. The Executive Secretary approved the revisions to the DMT Plan, and authorized use of Cell 4B on January 27,2011. 4.0 MONTHLY SLIMES DRAIN WATER LEVEL MONITORING I I t I t I I I 4.1 General f Part t.D.3(b)(1) of the Permit provides that the Permittee shall at all times maintain the average I wastewater recovery head in the slimes drain access pipes of each of Cells 2 and 3 to be as low I I 3 N:\Required ReportsU)MT Reports\2010 DMT Report\Q4 2010 DMT Report\Q4 2010 DMT Report draft.dOCX Tailings Cell Maximum Wastewater Elevation Measured During the Quarter (fmsl) Maximum Wastewater Elevation Permitted Under License Condition 10.3 (fmsl) Maximum Wastewater Elevation Permitted Under Part t.D.2 of the Permit (fmsl) Cell I s613.82 5,615.40 5,615.50 Cell3 5,604.54*5,602.50**5,605.50** Cell4,A 5.593. I 3 5.593.74**x 5.595.50 as is reasonably achievable, in accordance with the DMT Plan. Part I.D.3(b)(3) of the Permit provides that for Cell 3, this requirement shall apply after initiation of dewatering operations. Similarly, Part t.D.6(c) of the Permit provides that, after the Permittee initiates pumping conditions in the slimes drain layer in Cell 44, the Permittee will provide: l) continuous declining fluid heads in the slimes drain layer, in a manner equivalent to the requirements found in Part I.D.3(b), and 2) a maximum head of 1.0 feet in the tailings (as measured from the lowest point of the upper FML) in6.4 years or less. Part I.D.3(b)(2) of the Permit provides that the Permittee shall conduct a monthly slimes drain recovery test at each tailings cell that meets the following minimum requirements: l) includes a duration of at least 9O-hours, as measured from the time that pumping ceases, and 2) achieves a stable water level at the end of the test, as measured by three consecutive hourly water level depth measurements, with no change in water level, as measured to the nearest 0.01 foot. At this time, initiation of dewatering operations has not commenced in Cell 3 nor has the Mill initiated pumping conditions in the slimes drain layer of Cell 4A. As a result, the requirements in Part I.E.7(b) to monitor and record monthly the depth to wastewater in the slimes drain access pipes as described in Part I.D.3 of the Permit apply only to Cell 2 at this time. Accordingly, this Report is limited to slimes drain recovery head information relating to Cell 2 only. Pursuant to Parts I.E.7(b) and I.F.2 of the Permit, Section 8.2 of the DMT Plan and correspondence from DRC, dated February 7,2008, the results of monthly recovery monitoring of the slimes drain for Cell 2 are to be recorded and included with the results of quarterly monitoring in the quarterly White Mesa Mill DMT Performance Stondards Monitoring Report and Cell 4A BAT Performance Standards Monitoring Report (the "DMT Reports"). Further, beginning in 2008, quarterly DMT Reports must include both the current year monthly values and a graphic comparison to the previous year. An annual slimes drain recovery head report, that addresses the requirements of Part I.F.11 of the Permit and Section 8.2 of the DMT Plan must be included in the 4th quarter DMT Report. 4.2 Results for the Quarter In accordance with these requirements, the individual monthly slimes drain recovery head monitoring data for the Quarter, which includes the date and time for the start and end of the recovery test, the initial water level, and the final depth to stable water level, is included as Attachment C to this Report. Those data, as well as the data for the previous year, including the slimes drain recovery elevations ("SDRE"), are presented graphically in Attachment D. 4.3 Quality Assurance Evaluation and Data Yalidation Denison management has evaluated all slimes drain data collected, data collection methods, and all related calculations required by the Permit, and have verified the accuracy and reliability of both the data and calculations reported. I I I I I I I I I I I I I I I I I 4 N:\Required Reports\DMT ReportsU0l0 DMT Report\Q4 2010 DMT Report\Q4 2010 DMT Report draft.dOCX I I I I I t t I I I I T I I I I I I I I I As a result of its quality assurance evaluation and data validation review, Denison has concluded that all of the 2010 monthly and all of the 2009 monthly slimes drain tailings fluid elevation measurements set out in Tables 2 and 3 meet the test performance standards found in Part I.D.3(bX2) of the Permit and can be used for purposes of determining compliance with the requirements of Part LD.3(bX2) of the Permit. 4.4 Graphic Comparison to Previous Year A graph showing the final depth to stable water level readings for each month in 2010 atd2009, for which validated data is available (see Section 4.3 above), is included as Attachment D, which shows a graphic comparison of this Quarter's data to data for the previous year. 5.0 WEEKLY WASTEWATER LEVEL MONITORING: ROBERTS POND During the Quarter, Mill personnel monitored and recorded weekly the wastewater levels at Roberts Pond to determine compliance with the DMT operations standards in Part I.D.3(e) of the Permit. Part t.D.3(e) of the Permit provides that the water level in Roberts Pond shall not exceed an elevation of 5,624 fmsl. The maximum wastewater elevation measured in Robert's Pond during the quarter was 5,622.96 fmsl, which did not exceed the maximum permitted elevation of 5,624 fmsl. The results of such monitoring are included in Attachment A. 6.0 WEEKLY FEEDSTOCK STORAGE AREA INSPECTIONS AND INSPECTIONS OF FEEDSTOCK MATERIAL STORED OUTSIDE THE FEEDSTOCK STORAGE AREA Weekly feedstock storage area inspections were performed by the Mill's Radiation Safety Department, to conf,rrm that the bulk feedstock materials are stored and maintained within the defined area described in the Permit and that all alternate feedstock located outside the defined feedstock area is maintained within containers that comply with the requirements of Part I.D.l l of the Permit. The results of these inspections are recorded on the Weekly Mill Inspection forms, which are available at the Mill for inspection. No variance from the requirements of part I.D.l I was noted during the weekly feedstock storage area inspections. 7.0 TAILINGS CELLS AND POND LINER SYSTEM REPAIRS The liner systems at Cells l, 2, and 3 were inspected on a daily basis pursuant to the requirements of Sections 2.1 and2.2 of the Mill's DMT Plan. The results of those inspections are recorded on the Mill's Daily Inspection Data sheets, which are available at the Mill for review. A visual inspection of Roberts Pond was performed on a weekly basis. The results of those inspections are recorded on the Weekly Mill Inspection forms, which are available at the Mill for review. 5 N:\Required Reports\DMT Reports\2010 DMT Report\Q4 2010 DMT Report\Q4 2010 DMT Report draft.dOCX In accordance with Part I.8.7(f) of the Permit, in the event that any liner defect or damage is identified during a liner system inspection, the Mill shall immediately implement the currently approved Liner Maintenance Provisions. Further, Part l.F. 2 of the Permit provides that when a liner repair is performed at any tailings cell or at Roberts Pond, a Repair Report shall be prepared and included with the next quarterly DMT report. Mill personnel detected an accumulation of fluid in the LDS standpipe of Cell 1 on Wednesday, June 2, 2010. Transfer of fluids from Cell I to Cell 4,A. to lower the Cell I level sufficiently to detect and repair any damage began on June 2,2010. Maintenance identified some FML damage and performed repairs during the period when the level was lowest. Following the repairs, the level was allowed to gradually return to its June 3 level of 5614.57 feet and the LDS remained dry until, after a period of heavy rains in late July and early August (and an increase in the solution in level in Cell 1), a recurrence of the LDS liquid level was identified on August 7, 2010. At that time, Mill resumed pumping Cell 1 to Cell4A. to lower the solution level. During discussions on August 12,2010, DRC personnel agreed with Denison that both the June and August identifications of LDS solutions were part of one event. The temporary cessation of flow into the LDS between June and August detections may have resulted from lowering the solution level to a point below some tears or damage that were not identified during the July repair efforts. Denison submitted to DRC a plan and schedule for inspection and repair, if necessary, of the inside slope areas of the Cell I FML above the 5613 foot level, on August 18, 2010, and updated plan on August 30, 2010. DRC conditionally approved the updated plan in a letter dated September 22,2010. The updated plan commits to completion of the repairs by July 31,2012. The September 22 DRC letter and Part 1.F.2 of the groundwater discharge permit require that the repairs be documented in a liner repair report which shall be included with the next quarterly DMT report, that is, following completion of the repairs to be reported. Consistent with the proposed date for completion of repairs in July 2012, Denison will include the required repair report with the third quarter DMT report to be submitted on December 1,2012. During the Quarter, no liner repairs were performed at any of the Mill's tailings cells other than Cell 1. Consistent with the approved repair plan and schedule, repairs to the Cell I FML were conducted during the months of September and October 2010, ceased during the months of November and December 2010, and are scheduled to resume in the month of April 2011. DECONTAMINATION PADS Summary of Weekly Inspections Part I.F.7 (g) of the Permit and Section 3.1 of the DMT Plan requires that a weekly inspection of the New Decontamination Pad be performed, including that the vertical inspection portals on the New Decontamination Pad which are located between the primary and secondary containments be visually observed on a weekly basis as a means of detecting any leakage from the primary containment into the void between the primary and secondary containments. The BAT 6 N:\Required ReportsU)MT Reports\2010 DMT Report\Q4 2010 DMT Report\Q4 2010 DMT Report draft.dOCX 8.0 8.1 I t I I t I I I t t I T I I I I I t I I t I I performance standards for the New Decontamination Pad are set out in Part I.D.14 of the Permit. The New Decontamination Pad was placed into service on March 22, 2010. Use of the New Decontamination Pad was temporarily suspended during the second quarter 2010 as a result of a cease and desist order from DRC dated May 18, 2010. Because the New Decontamination Pad was not in use, the weekly inspections of the containments were stopped. Table 4 below indicates the water level measurements in each portal measured during the second quarter 2010 that correspond to the last usage of the New Decontamination Pad. The data have been maintained here for information purposes only. Table 2 - New Decontamination Pad Inspection Portal Level for the Second Quarter 2010 Date Portal I Liquid Level (in Feet)r Portal I Liquid Level (in Feet) Portal I Liquid Level (in Feet) 412l 0 0.00 0.00 0.00 4t9t 0 0.00 0.00 0.00 4/t6l 0 0.00 0.00 0.00 4/23/0 0.00 0.00 0.00 4/30/0 0.00 0.00 0.00 sl7/0 0.00 0.00 0.00 slt4l 0 0.00 0.00 0.00 5l2U 0 0.00 0.00 0.00 5t28t 0 0.00 0.00 0.00 6l4t 0 0.00 0.00 0.00 6/1v 0 0.00 0.00 0.00 6lt8/0 0.00 0.00 0.00 6t25t 0 0.00 0.00 0.00 L As per part LD. 14 of the Permit, the water level shall not exceed 0.10 foot above the cement floor in any LDS access pipe at any time. As can be seen from the foregoing table, no fluids were observed to be present in any of the portals during the second quarter. The New Decontamination Pad remained out of service during the third and fourth quarters. Any soil and debris identified during the weekly inspections was removed from the wash pad of the New Decontamination Pad, in accordance with part I.D.14 (a) of the Permit and Section 3.1 (eXi)(F) of the DMT Plan. No cracks greater than l/8" were observed during any weekly inspections. The Executive Secretary provided an authorization for use of the New Decontamination Pad in a letter dated February l, 2011. Use of the New Decontamination Pad is expected to resume in February 2011. 7 N:\Required Reports\DMT Reports9010 DMT Report\Q4 2010 DMT Report\Q4 2010 DMT Report draft.doCX I t I I I I I I t I I I I I I I 8.2 Annual Inspection of Existing Decontamination Pad I As required by Part I.F.l2 of the Permit, annual inspections of the existing decontamination were conducted during the second quarter 2010. The documentation for the annual inspections are reported in the Second Quarter DMT report submitted on August 30, 2010. 8.3 Annual Inspection of New Decontamination Pad As previously stated, the New Decontamination Pad was placed into service on March 22,2010. Use of the New Decontamination Pad was temporarily suspended as a result of a cease and desist order from DRC dated May 18, 2010. DRC's approval for use of the New Decontamination Pad was granted on February l,20ll, following submittal of revisions to the DMT Plan and DRC observation of hydrostatic testing of the in-ground water holding tanks. Revisions to the DMT Plan were submitted by Denison on November 12,2010 and reviewed by DRC. Hydrostatic testing was re-performed from November 24 to 26,2010 following a 10-day advanced notice to DRC on November 12,2010. As of December 31,2010 the New Decontamination Pad had not yet been approved for use. The New Decontamination Pad was taken out of service and inspected during the second quarter on April 13,2010 to ensure integrity of the wash pad's exposed concrete surface, as required by Paft I.F.l2 of the Permit and Section 6.5 of the DMT Plan. No abnormalities were identified. No significant cracks (greater than 1/8 inch), deterioration or damage were identified. No repairs were required at the time of the inspection. A few minor cracks (less than 1/8 inch) were observed. These minor cracks are being monitored to determine whether they expand over time and require repair. 9.0 CELL 4A BAT PERFORMANCE STANDARDS REPORT FOR THE QUARTER This Section constitutes the routine Cell 4A BAT Perforrnance Standards Monitoring Report for the Quarter, as required under Part I.F.3 of the Permit. 9.1 LDS Monitoring 9.1.1 Operational Status of LDS Pumping and Monitoring Equipment The LDS pumping and monitoring equipment, including, but not limited to, the submersible pump, pump controller, head monitoring, and flow meter equipment operated continuously during the Quarter. During the Quarter, there were no failures of any pumping or monitoring equipment not repaired and made fully operational within 24-hours of discovery, as contemplated by Part I.E.8(a)(1) of the Permit. I I I I I I I I I I I I t t I 8 N:\Required Reports\DMT ReportsV0l0 DMT Report\Q4 2010 DMT Report\Q4 2010 DMT Report draft.dOcx t t I I I I T I I T I I T I I I I T I t I 9.1.2 Measurement of Weekly Fluid Head at the Lowest Point in the Secondary Membrane The readings pertaining to the fluid head above the lowest point in the secondary FML for Cell 44 are provided in Attachment F. As can be seen from a review of Attachment F, at no point in the Quarter did the fluid head in the Cell 4,A. LDS sump exceed a l-foot level above the lowest point in the lower FML on the Cell floor (where for purposes of compliance monitoring this 1- foot distance equates to 2.28 feet above the LDS system transducer), as stipulated by Part I.E.S(a)(2) of the Permit. During the Quarter, the fluid head in the Cell 4,A. LDS sump did not exceed 9.6 inches above the LDS transducer. 9.1.3 Measurement of the Volume of Fluids Pumped from the LDS The readings pertaining to the volume of fluids pumped are provided in Attachment F. As can be seen from a review of Attachment F, during the Quarter, the average daily LDS flow volume did not exceed 24,160 gallons/day, as stipulated by Part I.E.8(a)(3) of the Permit. Based on the maximum head recorded on the FML during the Quarter of about 37 feet, the allowable flow rate would actually be approximately 23,955 gallons per day, as determined under the Mill's Cell 4A BAT Operations and Maintenance Plan, Table 1A (also included in Attachment F of this report), and assuming a liner elevation of 5555.55 feet and approximately 39.66 acres of liquid area. For fourth quarter 2010, a total of 0 gallons were pumped. 9.2 Measurement of Weekly Wastewater Fluids in Cell4A Weekly fluid elevations for Cell 44. are provided in Attachment A along with elevations for Cells I and 3 and Roberts Pond. During the Quarter, the Mill operated and maintained wastewater levels in Cell 44. to provide the minimum vertical freeboard as required by Part I.E.8(aXa) of the Permit. See the discussion in Section 3 above. 9.3 Slimes Drain Recovery Head Monitoring As the Mill has not initiated pumping conditions in the Cell 44. slimes drain system at this time, monthly recovery head tests and fluid level measurements are not required to be made at this time pursuant to Part I.E.8(b) of the Permit. 1O.O ANNUAL SLIMES DRAIN RECOVERY HEAD REPORT FOR THE CALENDAR YEAR 2O1O This Section constitutes the annual slimes drain recovery head report for calendar year 2010 (the "Period"), as required under Parts I.D.3 (b) and I.F.l I of the Permit and Section 8.2 of the DMT Plan. 9 N:\Required Reports\DMT Reportsg0l0 DMT Report\Q4 2010 DMT Report\Q4 2010 DMT Report draft.dOCx 10.1 Individual Slimes Drain Recovery Head for 2009 The individual monthly slimes drain recovery head monitoring data for the Period, which includes the date and time for the start and end of the recovery test, the initial water level, and the final depth to stable water level, is included as Attachment C to this Report. The equivalent recovery water level elevation is determined by subtracting the final depth to stable water measurement from the sheets in Attachment C or D from 5614.83 fmsl, being the surveyed elevation of the measuring point. Those elevations are set out in Tables 3 and 4 below. 10.2 Average Slimes Drain Recovery Head for 2010 The simple average of the slimes drain recovery head for Cell 2 for the Period was 5603.49 fmsl. By comparison, the simple average slimes drain recovery head for the year immediately prior to the Period was 5603.23 fmsl, using data that meet the test performance standards found in Part I.D.3(b)(2) of the Permit. See Section 10.4 below. 10.3 Time Series Chart Included in Attachment D is a time series chart that shows trends in the monthly recovery water level elevations in the Cell 2 slimes drain over time, using data that meet the test performance standards found in Part I.D.3(bX2) of the Permit. See Section 10.4 below. 10.4 Quality Assurance Evaluation and Data Validation Denison management has evaluated all data collected, data collection methods, and all related calculations required by the Permit, and have verified the accuracy and reliability of both the data and calculations reported. Based on these evaluations, the following observations were made: The monthly tailings fluid elevation measurements for each month in 2010 were reviewed and found to meet the test performance standards found in Part I.D.3(bX2) and to be suitable for use in demonstrating compliance status in Section 10.5 below. As a result of its quality assurance evaluation and data validation review, Denison has concluded that: 1. All of the 2009 monthly slimes drain tailings fluid elevation measurements meet the test performance standards found in Part I.D.3(bX2) of the Permit and can be used for purposes of determining compliance with the requirements of Part I.D.3(bX2) of the Permit. 2. All of the 2010 monthly slimes drain tailings fluid elevation measurements meet the test performance standards found in Part I.D.3(b)(2) of the Permit and can be used for purposes of determining compliance with the requirements of Part I.D.3(b)(2) of the Permit. 10 N:\Required Reports\DMT Reports\2010 DMT Report\Q4 2010 DMT Report\Q4 2010 DMT Report draft.dOCX I t I I I I I I I I I t I I I I I I I I I t I I I I I I I I I I I I I I t I 10.5 Demonstration of Compliance Status with the Requirements of part I.D.3(b) and I.E.7(b) of the Permit 1 0.5. I Permit Requirements Part I.D.3 f the Permit provides that annual slimes drain compliance shall be achieved when the average annual wastewater recovery elevation in the slimes drain access pipe, as determined pursuant to the DMT Plan, meets the conditions in Equation 1, below: Equation 1: [IE, + Ey-r * Zy-zf lNy +Ny-r *Nv-z] < [xEv-1 *Iy-2t Zy-tllNy-r rNy-z+Ny-:J Where: IEv : IEv-r: IEv-z: IEv-:: Nv-r = Nv-z : year ofinterest. Ny Total number of SDRE tests that meet the test performance standards found in Part I.D.3(b)(2), conducted during the calendar year of interest. Sum of all monthly slimes drain tailings fluid elevation measurements that meet the test performance standards found in Part I.D.3(b)(2), during the calendar year of interest. Hereafter, these water level measurements are referred to as slimes drain recovery elevations (SDRE). Pursuant to the DMT Plan, these recovery tests are to be conducted monthly and the SDRE values reported in units of feet above mean sea level (amsl). Sum of all SDRE measurements made in the year previous to the calendar year of interest. Sum of all SDRE measurements made in the second year previous to the calendar year of interest. Sum of all SDRE measurements made in the third year previous to the calendar Total number of SDRE tests that meet the test performance standards found in Part I.D.3(bX2), conducted in the year previous to the calendar year of interest. Total number of SDRE tests that meet the test performance standards found in Part I.D.3(b)(2), conducted in the second year previous to the calendar year of interest. Total number of SDRE tests that meet the test performance standards found in Part I.D.3(b)(2), conducted in the third year previous to the calendar year of interest. Nv_: : TL N:\Required Reports\DMT ReportsU0l0 DMT Report\Q4 2010 DMT Report\Q4 2010 DMT Report draft.dOCX I I I Part I.D.3 further provides that prior to January 1,2013, the following values for E and N in Equation I shall be based on SDRE data from the following calendar years. Table 3 - SDRE Data to be Used for Certain Years Report for Calendar Year Source of Data By Calendar Year for Equation 1 Variables (right side) Ev-t Ev-z Ev-r Nv-t Nv-z Ny-: 2010 2009 2009 2009 2009 2009 2009 20t1 2010 2009 2009 20t0 2009 2009 20t2 2011 20t0 2009 20rl 20t0 2009 Part I.D.3 provides that failure to satisfr conditions in Equation 1 shall constitute DMT failure and non-compliance with the Permit, and that for Cell 3, this requirement shall apply after initiation of de-watering operations. 10.5.2 Demonstration of Compliance with Permit Requirements 2010 SDRE values that meet the test performance standards found in Part I.D.3(bX2), reported in units of FMSL are as follows: Table 4 - Cell2 Slimes Drain Recovery Head and SDRE Values for 2010 12 N:V{equired Reports\DMT Reports\2010 DMT Report\Q4 2010 DMT Report\Q4 2010 DMT Report draft.dOCX I I I t I I I t I I t I I I I t 2010 Test Closing Date Elevation of Measurement Point Reported Final Depth to Stable Water Level SDRE Values Renorted as fmsl ll15l20t0 5"614.83 t3.96 5,600.87 2t2U2010 5.614.83 12.50 5,602.33 3lt5t20t0 5.614.83 I 1.04 5,603.79 4lt2l20t0 5,614.83 10.40 5,604.43 5lt9l20r0 5,614.83 10.43 s.604.40 6/30/2010 5.614.83 10.13 5.604.70 8t2/2010 5,614.83 10.74 5.604.09 8125t2010 5.614.83 10.65 5,604.18 912412010 s.614.83 l 1.50 5.603.33 t0125120t0 5.614.83 t2.35 5602.48 tU23t20t0 5.614.83 10.81 5604.02 12t22t2010 5.614.83 I 1.58 5603.25 IEzoro : 67,241.87 Nzoro:12 2009 SDRE values that meet the test performance standards found in Part I.D.3(bX2), reported in units of FMSL are as follows: Table 5 - SDRE Values for 2009 Based on the foregoing, it is evident that lEzoro : 67,241.87 fmsl, and Nzoro : 12, and that lEzooq: 67238.8 fmsl, and N2s6e: 12 Also, based on Table 2 above, for year 2010, Ey-r : Ey-z: Ey-:, that is all are to be based on 2009 data, and Ny-l : Ny-2 : Ny-:, that is, all are to be based on 2009 data Based on these values, equation 1 can be applied as follows: [IEv+ IEv-r + fEy-z ]/ [Nv +Ny-r +Ny-zl:167,241.87 + 67,238.8+ 67,238.8]/[12 + 12+12] :5603.32 fmsl and [IEy-r + fEy-z + )Ey-: ] / [ Ny-r + Ny-z + Ny-: ]:167,238.8 + 67,238.8 + 67,238.811U2 + 12 + l2l:5603.23 fmsl Although 5,603.32 fmsl is essentially the same level as 5,603.23 fmsl, it is 0.09 foor (1") higher. Therefore, annual slimes drain compliance has not been achieved for 2010, in accordance with Part LD.3 of the Permit. However, for the reasons discussed below, Denison believes that the 13 N:\Required Reports\DMT Reports\2010 DMT Report\Q4 2010 DMT Report\Q4 2010 DMT Report draft.dOCX 2009 Test Closing Date Elevation of Measurement Point (fmsl) Reported Highest Level (feet) SDRE Values (Reported as fmsl) U3012009 5614.83 11.25 5603.58 2127t2009 5614.83 9.35 s605.48 312812009 5614.83 8.84 5605.99 4t27t2009 5614.83 11.98 5602.85 s12012009 5614.83 10.28 5604.55 6t22t2009 s614.83 13 s601.83 713012009 s614.83 t3 5601.83 813U2009 5614.83 1 1.04 5603.79 9t28t2009 s614.83 1r.46 s603.37 t013012009 5614.83 13.3s 5601.48 tU2312009 5614.83 12.49 s602.34 1211412009 5614.83 13.12 s60r.7t FErooq :67.238.8 Nroos :12 monitoring requirements of Part I.D.3(b)(2) seriously interfere with Denison's ability to comply with Parts I.D.3(b)(i) and I.D.3 (b)(3) and should be amended. Part I.D.3(b)(2) of the Permit requires that each slimes drain monthly monitoring test: l) includes a duration of at least 90-hours, as measured from the time that pumping ceases, and2) achieves a stable water level at the end of the test, as measured by three consecutive hourly water level depth measurements, with no change in water level, as measured to the nearest 0.01 foot. It should be noted that, in 2010, order to meet the test requirements: l. The slimes drain pump has remained off an average of 6.42 days per month every month for performance of the measurements, and 2. This means that the slimes drain pump remains off approximately 77 days (11 weeks) per year or 20 percent of the year for performance of measurements. That is, in order to meet the requirements for testing in Part I.D.3(b)(2) of the Permit, it has not been possible to run the slimes drain pump often enough to meet the requirement in Part I.D.3(b)(l) of the Permit that Denison maintain the average wastewater recovery head in the slimes drain access pipe as low as reasonably achievable, when the pump can only be run 80% of the time. That is, the monitoring requirement to demonstrate the slimes drain level has been reduced, seriously interferes with the pumping needed to reduce the slimes drain level. Nonetheless, even with the limitation of operating only 80% of the year due to the monitoring constraint, the Mill has maintained the slimes drain at an approximately constant level. It is anticipated that if the monitoring constraint were modified to allow more pumping time, compliance with the Part LD.3(b) requirements could be achieved. Denison recommends that the monitoring requirement in the Permit be modified to allow the slimes drain pump sufficient running time to dewater the cell. For example, the monitoring requirement could be reduced from monthly to quarterly. This would reduce the downtime to approximately 26 days per year, or increase the pumping time to 339 days per year, or 93Yo,which would help. In addition, the following factors should be noted: I . The slimes drain elevation measured at the end of 2010 was lower than the slimes drain elevation measured at the beginning of 2009, indicating an overall reduction in elevation; 2. For both 2009 and 2010 there appeared to be a rise in elevation over the period from January through March, followed by a reduction over the remainder of the year. The rate of reduction for the remainder of the year in 2010 was lower than in 2009, possibly due to the significantly higher precipitation experienced in 2010 of 15.13 inches compared to the 2009 total precipitation of 8. 1 3 inches. The Mill was able to maintain the 20 1 0 slimes drain recovery level within I inch of the preceding year's level despite the fact that the annual precipitation was 7 inches (186%) higher than the preceding year. I T I I I I t T I I I I I I I t4 N:\Required Reports\DMT Reports\2010 DMT Report\Q4 2010 DMT Report\Q4 2010 DMT Report draft.dOCX t I I t I I I I I I I I I I I I I I t I I I I 11.0 SIGNATURE AND CERTIFICATION This document was prepared by Denison on February 25,2011. Denison By: ) Corp. David C!lund Vice PresidentlRegulatory Affairs and Counsel CERTIFICATION: I certify, under penalty of law, that this document and all attachments were prepared under my direction or supervision in accordance with a system designed to assure that qualified personnel properly gather and evaluate the information submitted. Based on my inquiry of the person or persons who manage the system, or those persons directly responsible for gathering the information, the information submitted is, to the best of my knowledge and belief, true, accurate and complete.. I am that there are significant penalties for submitting false information, including ilfllity of fine and imprisonment for knowing violations. David Vice President, \pgulatory affairs and Counsel 15 N:\Required Reports\DMT Reports\2010 DMT Report\Q4 2010 DMT Report\Q4 2010 DMT Report draft.doCX Denison Mines (USA) Corp. Tab A I I I I I t I I I I I I I I I t I I I Tailings Pond Elevations 4th Quarter Elevations Date Free Board 1 10t1t2010 10t8t2010 10t15t2010 10t22t2010 10129t2010 11t5t2010 11t12t2010 11t19t2010 11t26t2010 12t3t2010 12t10t2010 12t17t2010 12t23t2010 12t31t2010 Cell 1 Gell 3 Roberts Pond Cell 4A 5615.40 5602.50 5624.00 5593.74 5613.45 5604.41 5617.97 5588.75 5613.81 5603.23 5618.39 5588.73 5612.38 5604.47 5617.98 5589.675613.34 5604.43 5618.48 5589.695613.44 5603.21 DRY 5589.94 5613.44 5603.35 5619.42 5589.915613.38 5604.14 5619.64 5590.185613.49 5604.54 5620.48 5590.475613.51 5602.02 5620.53 5591.015613.48 5602.59 5620.78 5591.31 5613.48 5602.88 5622.84 5591.855613.48 5602.98 5622.96 5592.03 5613.67 5603.66 5622.14 5592.635613.82 5603.92 5622.28 5593.13 Notes: 1. Freeboard as permitted under License condition 10.3 2. The Mill has filled Cell 3 to its final tailings solids capacity in preparation for closure, and pre-closure activities are underway. There is no remaining pool area of any significance in Cell3. Tab B I I I I I I I I I I I I I I T I I I I This attachment has been deliberately left blank. Tab C I I I I I I I I I I I I T I I I I I I I I I MONTHLY HEAD MEASUREMENT TEST Location: January-10 Date:LlLslzOtO Slimes Cell # 2I Sampler:Tanner Holliday Ryan Palmer I I LlLtlzOtO L/L2/2OLO tlL3/2OL0 !/L4/2OLO uLslzoL0 - -- L4.42 13.96 600 700 800 900 1_OO0 1100 1200 1300 1400 1500 1500 24.75 - L7.53 - L7.4 L5,4L 24.O5 15.39 L4.4 13.96 - 13.96 - 13.96I23.37 - 22.72 77.28 15.35 - 75.29 - 15.25 1.4.39 t I 22.23 77.L6 - 17.o3 - L6.92 L4.37 - 14.35 t4.342L.7t 2L.24 16.79 - 16.65 - L6.52 15.19 L5.L2 20.87 15.03 14.26 L4.24 I - 13.96 I I Comments: The Reporting number is 13.96 I I I I I T I MONTHLY HEAD MEASUREMENT TEST t I I t Location: Slimes Cell# 2 Date: 2l2Ll2O1O Sampler: Tanner Holliday Ryan Palmer 2!s!l:oLo 2/16/2oto 2/77l2oto zlLylzoto zltslzoLo 2/2ol2o7o 2lztl2oLo I 600 I700 L7.55 75.47 L4.4 13.66 13.05 r800 -G -z5t',G-;:;; -I 900 24.34 77.31 1s.4 L4.34 13.63 t3.O2 I1000 23.9L L7.2 15.35 L4.3 13.61 1100 23.32 17.08 15.31 L4.27 13.s8 1200 G---?E---.;;Eru-1ffi 1300 22.06 16.81 15.19 14.t8 13.54 1400 21.65 L6.7 15.12 L4.t5 13.48 '-- I1500 2L.72 16.59 15.05 14.08 73.43 1500 L2.5 t2.5 I I t I I I t I I I Comments: The report number is 12.5 it took longer than usual to stablize I don't know if the weather had anything to do with this or not? I I MONTHLY HEAD MEASUREMENT TEST I I I I I I Location: Slimes Cell# 2 Date: Sampler: 3lLOlzOtO3/8/2olo 3lsl20t9 3/Ls|2OLO Tanner Holliday Ryan Palmer 3lLLlzOtO 3lt2/2}Lo 3lL4/2OtO 3l7s/2OLO 600 700 800 900 1000 1100 1200 1300 1400 1_500 1600 L2.46 L2.46 \2.46 12.30 L2.26 L2.23 - LL.O4 - LT.O4 L6.47 - 16.31 L4.O9 13.07 16.15 15.00 t5.79 L4.06 14.03 L3.97 13.90 - 13.82 L3.75 13.58 13.61 L3.O7 t3.o7 13.03 13.00 12.97 72.93 72.89 lL.O4 13.05 72.43 t2.40 12.35 23.73 23.27 22.s3 21.80 21.3L L5.76 - L5.64 L5.52 -iF4'- I I I t I I I 11.09 - LL.O4 - Comments: Three consecutive readings was obtained earlier in the week but the 90 hrs had not been reached. The pump remained off during the weekend, one reading was taken on Sunday the 14th at 1730 hrs. Monday Morning we achieved three consecutive readings once again and by this time the 90 hr requirement was also meet. The reading at this time was 11.04 which will be the reporting number for this recovery test. I I I I MONTHLY HEAD MEASUREMENT TEST Location: Slimes Cell# 2 Date: Sampler: 4lL2l^OLO Tanner Holliday 4lslzot} 4/6|2OLO 4/7lzOLO 4/8l20LO 4lel2oL0 4lL2|20LO 600 700 800 900 1000 L100 L200 1300 1400 1500 1500 20.83 20.37 15.29 19.93 75.2 15.38 13.81 -- L3.78 L2.78 \2.76 11.88 LO.4 13.75 12.7 11_.85 10.4 19.58 15.09 L3.7 L2.67 11.83 L9.23 L4.99 13.66 73.62 L2.62 11.8 18.85 L4.9 12.58 7L.77 18.57 14.81 - 18.2L L4.73 13.56 13.5 L2.5L L7.73 t2.47 11.69 77.93 14.65 73.44 LL.64 Comments: Additional readings were taken over the weekend, each day had one reading taken. On the 10th the level was 11.41 the reading on the 11th was LO.77. t2.39 The report number was 10.4 for the month of April. I I I MONTHLY HEAD MEASUREMENT TEST 11.3 13.68 73.64 I t I t I t I I I I Location: Slimes Cell# 2 slt1l2oto sl].tl2oL1 slt2lzoto slLg|aOLO Tanner Holliday, Ryan Palmer sh4/20t0 5lt7l201o sl78lz}t9 sllslzoTo Date: Sampler: slt3l2olo 600 700 800 900 1000 1100 1200 L300 1400 1500 1500 L7.29 17.08 16.93 t6.75 16.50 15.06 13.07 14.98 13.85 13.04 14.90 13.82 13.00 11.35 10.78 10.4313.87 13.8 13.75 LL.34 L0.77 71.32 10.75 10.43 14.85 - 14.79 t2.96 to.72 72.93 12.90 17.24 10.58 lL.27 10.7 23.64 22.95 L6.47 L6.34 L6.23 15.13 -- 14.72 L3.7t 14.66 14.60 - t4.54 13.59 12.85 7t.27 L2.82 L2.80 - 11.13 L0.62 r1.17 - Comments: The report number is 10.43 When the slimes test was started it was found that the main breaker was tripped. lt was determined that the breaker couldn't have tripped to long ago based on the first depth reading of 23.64I I I I I I I MONTHLY HEAD MEASUREMENT TEST I I Location: Slimes Cell# 2 Date:6l30l20to I I I Sampler: TannerHolliday Garrin Palmer, Ryan Palmer 6l2t/2}t} 6/22l2OtO 6123/2OtO 6/24/2OtO 6/2sl20Lo 6128/2OtO 600 700 800 900 1000 1100 L200 1300 1400 1500 1600 23.37 L4.97 13.3 L2.3t 11.55 10.13 22.LL 14.88 13.3 L2.29 11.56 10.13 -- - I I I I 2L.36 14.80 13.2 \2.26 11.55 10.13 20.66 L4.7L L3.2 t2.23 LL,52 20.01 14.62 13.L L2,L9 11.48 t9.62 L4.53 13.1 72.t5 L]-.45 19.13 t4.43 13.0 L2.LO Lt.47 t8.7L L4.34 13.0 L2.O6 11.38 L8.29 t4.27 L2.9 12.O2 11.35 10.13 I I I I I Cor."ntt At 1120 and the measurement was 10.90. t I I I I MONTHLY HEAD MEASUREMENT TEST I I I t I I I I I T I I I I I t I I t Location: Slimes Cell # 2 7126lLo-8lzlLo Tanner Holliday Garrin Palmer 7lzelzoLo 7l3Ol20L0 8/L{2OLO7l26l2oto 7/27lzoto 16.09 23.95 15.99 Date: Sampler: 7l28l2OLO - 14.t9 14.t5 812/zo1:o 600 700 800 900 1000 1100 1200 1300 1400 1500 1600 13.16 L2.32 LO.74 LO.74 - 10.74 13.13 12.30 23.18 22.25 15.90 15.82 LA.!O 13.10 72.28 L2.24 L2.2215.64 14.00 13.05 13.01 12.98 12.27 L2.94 L2.L4 L2.86 L2.LO t2.82 12.05 14.05 2L.6L 20.99 1s.s3 20.55 15.42 13.95 L3.89 13.83 L3.77 20.13 L9.79 L5.32 - t5.24 10.94 LO.74 Comments: Report number that will be used is LO.74 MONTHLY HEAD MEASUREMENT TEST Location: Slimes Cell# 2 Date: Sampler: 8/27lzlLo8l2sl207} 8/26|2OLO 8l28lzOtO 8/2sl2OLO Tanner Holliday Garrin Palmer 8l2el2o1o 8/3Ol2OtO 8/3L/2O1O eltlzlll 15.85 L3.92 LL.46 11.08 t5.75 13.88 13.83 lL.43 11.06 2L.85 15.61 LL.42 11.05 10.55 21.40 15.50 L3.77 L1,.40 LL.O4 600 700 800 900 1000 1100 L200 1300 1400 1500 1500 20.96 L5.44 13.70 11.38 11.03 20.38 15.34 13.62 11.36 It.32 11.00 10.97L9.97 15.25 13.58 I t I I I I I I I I I I I I t I I I I 13.45 7L.29 10.9515.15 L3.5219.58 79.23 15.04 11.56 LL.25 10.93 10.65 Comments: Slimes Drain was started a little late on the 25th of August. The full test was completed on September 1st 2010. the report number is 10.65 for this, August 2010. I I t MONTHLY HEAD MEASUREMENT TEST Location: Slimes Cell# 2 Date: Sampler: e/24/2OLO I Tanner Holliday Garrin Palmer I I I 9|2O/2O7O 9l2t/2OLO 9l22l21t} 9/2312010 9l24l2O1O _ 600 700 800 900 1000 1100 1200 1300 1400 1500 1600 - 15.35 L3.O7 11.99 11.98 - 11.50 25.9s 23.78 15.20 13.00 11.50 15.06 14.90 L4.77 L2.95 - L2.90 tt.97 11.50 23.22 I 22.30 12.85 1L.94 2L.48 20.67 14.65 L2.79 - L2.73 tL.92 11.8914.52t20.32 t4.40 L4.28 t2.67 Lt.87 L9.75 t2.67 LL.84 I I I Comments:Report number that will be used is 11.50 I I I T t I I MONTHLY HEAD MEASUREMENT TEST Location:Date: Sampler: LO/2s/2010 Slimes Cell# 2 Garrin Palmer Tanner Holliday LO/L8/2OL0 7O|Lq/}OLO LO|1O(1OilO LO/2L/2O7O LO/22/2OLO 16.77 14.87 13.91 13.09 12.35 16.L4 74.8L L3.87 12.35 16.08 14.80 13.84 13.06 72.35 600 700 800 900 1000 1100 L200 r.300 1400 1500 1600 76.02 L4.76 L4.72 13.78 15.89 L3.74 13.82 13.03 L2.9915.96 t2.96 15.81 14.59 L3.70 12.93 L5.72 14.55 15.65 t4.49 13.65 L2.89 13.60 12.85 Comments: when test was started the breaker was found tripped. That's why the beginning levels were up from what they normally start at. The reporting nubmer is 12.35 I t MONTHTY HEAD MEASUREMENT TEST t I I Location: - Slimes Cell# 2 Date: Samplen 7u23l2OL0 Garrin Palmer Tanner Holliday LLI!6|2OilO tuluzAfi fl11812070 tTltelzot0 LLlZLlzOtl 7tl22l20Lo I Goo ------ 700 28.60 15.98 13.84 12.63 10.81 ------ r 800 25.82 15.84 13.78 12.s8 10.81I ------ I 900 25.33 15.7L 13.77 L2.54 10.81 lllllllllllllllllllll-----1000 24.45 1s.s8 13.66 12.51f 11oo --il; -iil; -iffi'---EF - I 12oo .:-i:t'....,.'...E ---i53I-:r.lm - - - --- 1300 22.49 15.19 13.46 12.3sf ----- I 14oo z:..s7 15.07 13.3s tz.3zI ------ 1500 21.28 14.95 13.31 L2.25 10.95 ------ I 1600 I Comments: I I I I I I I I MONTHTY HEAD MEASUREMENT TEST I I Location: - Slimes Cell# 2 Date: Sampler: t2l22l20LO I I t I t I I t Tanner Holliday Garrin Palmer tzlt3lzDl0 tzlI^4lz}t0 tallslzota nl$lzo7o 72lt7l2oL0 72l2Ol2OtO 600 ------ 700 29,10 17.s0 15.08 14.05 13.32 11.s8 ---E-- 800 27.75 t7.?7 15.04 14.04 13.31 11.58 ------ 900 26.70 17.24 15.00 14.01 13.30 11.s8 ------ 1000 25.75 17.10 14.9s 13.98 13.29 ------ 1100 24.90 16.93 14.87 13.93 t3.26 ------ 1200 24.39 15.75 14.80 13.87 13.23 --- -- 1300 23.70 16.65 14.73 13.83 13.19 --- -- !400 23.24 16.55 t4.70 13.79 13.16 ------ 1500 22.62 L6.43 14.68 13.76 L3.L2 ----- 1600 t Comments: Report number is 11.58 I I I I t I I I Tab D I I I I I t I I I I I t I I I I I I I --1 I I I 0T0zlfflzr or0z/08/tr fi\(.lrL/01 or0zl0E/6 0t0zltEl8 filzlrelL 0102/08/9 0TozltE/s ofizllelv 0t0zlrElE 0\oz/82lz OTOZ/IEIT 6002/rtlzr 6002/0Eltt 600ZITE/OT 600zloEl6 6002/rE/8 600z-/TE/L 600zl0ele 600ZITE/S 600zloe/n 6002/rE/e 6002/82/z 600zloElr or{oNd cllooN I .s(uLo tao .Eln N o(J N .9 o!t (EoC = I N o'- OJV' + i I I I---,+*-- - -- t I I I I I I t I I t I I I I T T I t This attachment has been deliberately left blank. I I I t I t I I I I I I I I I t t I I I t I t I I I I I I t I I I I I I I T Cell 4A LDS monitoring information Fourth Quarter 2010 October 2010 Date Measurements in lnches Flow Meter in Gallons tolLlLo 3.0 LO/8/!O 4.4 \O|L'/LO 4.L 7ol22lto 7.O LO/Z9/!O 7.3 2608s0 Lowest level for the month was 3.0 inches. Total number of gallons pumped was 0. November 2010 Date Measurements in lnches Flow Meter in Gallons 2608s0 260850 2508s0 260850 260850 260850 260850 260850 |L/s/to 7.7 LL|LL|LO 7.7 7L/t9/L0 8.3 71/26lLO 8.4 Lzl3lLO 8.e LZ|LOILO 9.2 t2/t7/LO 9.0 L2/23(LO s.5 LZ|3L|LO s.4 Lowest level for the month was 6.9 inches. Total number of gallons pumped was 0. December 2010 Date Measurements in lnches Flow Meter in Gallons 250850 260850 2608s0 260850 260850 Lowest level for the month was 8.3 inches. Total number of gallons pumped was 0. For the 4th Quarter 2010, the lowest level was 3.0 inches and a total of 0 gallons were pumped. GoosyntarConsultaag T.bhlA Calculated Action Lrakagc iatls for Varhur Head Condltionr Cell4A, Whlte Mera MIll ElaMlng Utah Heed Abova Unsr syrtsm (fea0 Celculrtrd Aclon l$rhrlr tttte fiellonr/rcn/dryl 5 22?.,W 10 314.0 15 384,s8 20 t144.08 25 496.5 30 543.t8 35 587.5 37 604.0 Tab G This attachment has been deliberately left blank. I t I t I I I I I I T I t I I t t T t