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HomeMy WebLinkAboutDRC-2014-007061 - 0901a068804c1185Department of Environmental Quality Amanda Smith Executive Director State of Utah GARY R. HERBERT Governor DIVISION OF RADIATION CONTROL Rusty Lundberg Director SPENCER J. COX Lieutenant Governor MEMORANDUM FROM: TO: Phil Goble Dean Henderson W DRC-2014-007061 0 DATE: April 24, 2014 SUBJECT: Review of the 4th Quarter 2013 Chloroform Monitoring Report for the Chloroform Contamination Investigation, Energy Fuels Resources (USA) Inc. ("EFR") White Mesa Uranium Mill, near Blanding, Utah The Utah Division of Radiation Control ("DRC") has reviewed the February 21, 2013, 4th Quarter 2013 Chloroform Monitoring Report ("Report") for the Chloroform Contamination Investigation. For the review of this report the following regulatory enforcement documents were used: • EFR was issued Ground Water Quality Discharge Permit No. UGW370004 ("Permit") on March 8, 2005; last revised on June 8, 2013. • The EFR Quality Assurance Plan ("QAP") June 7, 2012 (Revision. 7.2) REVIEW Monitor Well Sampling The following monitor wells were sampled as required in the QAP (see Table 1 below): TW4-1, TW4-2, TW4-3, TW4-4, TW4-5, TW4-6, TW4-7, TW4-8, TW4-9, TW4-10, TW4-11, TW4-12, TW4-13, TW4-14, TW4-16, TW4-18, TW4-19, TW4-20, TW4-21, TW4-22, TW4-23, TW4-24, TW4-25, MW-4, MW-26 (formerly TW4-15), MW-32 (formerly TW4-17), TW4-26, TW4-27, TW4-28, TW4-29, TW4-30, TW4-31, TW4-32, TW4-33, and TW4-34. The following monitoring wells were purged using the three approved QAP well purging strategies and meet QAP requirements for each strategy: 195 North 1950 West • Salt Lake City, UT Mailing Address: P.O. Box 144850 • Salt Lake City, UT 84114-4850 Telephone (801) 536-4250 • Fax (801-533-4097 • T.D.D. (801) 536-4414 www.deq.utah.gov Printed on 100% recycled paper Page 2 1. Purging two casing volumes with stable field parameters for specific conductivity, turbidity, pH, redox potential, and water temperature (within 10% RPD): Wells: MW-32, TW4-1, TW4-5, TW4-8, TW4-9, TW4-11, TW4-12, TW4-16, TW4-18, TW4-21, TW4-23, TW4-28, and TW4-32. 2. Purging a well to dryness and stability of field parameters for pH, specific conductivity, and water temperature only after recovery: Wells: TW4-2, TW4-3, TW4-6, TW4-7, TW4-10, TW4-13, TW4-14, TW4-26, TW4-27, TW4-29, TW4-30, TW4-31, TW4-33, and TW4-34. 3. Pumping Wells: MW-4, MW-26, TW4-4, TW4-19, TW4-20, TW4-22, TW4-24, and TW4-25. The water samples for the above wells were analyzed for the following constituents as required in the QAP: Chloroform, Chloromethane, Carbon tetrachloride, Methylene chloride, Chloride and Nitrate plus Nitrite as Nitrogen. Use of analytical methods is consistent with the requirements of the QAP requirements. QAQC Holding Times The method holding times for each parameter for samples collected at each monitor well were received and analyzed within the required holding times in the QAP. Receipt Temperature All samples were received within the required QAP temperature limit of 6° C. Detection Limits All analytes were measured and reported to the required reporting limits. However, several sets of sample results had the reporting limit raised for at least one analyte due to matrix interference and/or sample dilution. In all cases the reported value for the analyte was higher than the increased detection limit. Sample Duplicates Two duplicate samples were collected. Well MW-32 and its duplicate sample TW4-65, TW4-16 and its duplicate sample TW4-70. All analytical results for the two sample/duplicate pairs were within the 20% acceptance limits as required in the QAP (see Table 2 below). Groundwater Head Monitoring Depth to groundwater was measured in the following wells and/or piezometers, as required in Part I.E.3 of the Permit: Page 3 • The quarterly groundwater compliance monitoring wells. • Existing monitoring well MW-4 and all of the temporary chloroform investigation wells. • Piezometers P-l, P-2, P-3, P-4 and P-5. • MW-20 and MW-22. • Nitrate monitoring wells. • The DR piezometers which were installed during the Southwest Hydrologic Investigation. In addition, weekly and monthly depth to groundwater measurements were taken in MW-4, MW- 26, TW4-4, TW4-19, TW4-20, TW4-22, TW4-24, and TW4-25 and TWN-2. Mass Removed Chloroform removal was first estimated from the first quarter 2007. Since that estimation the mass removed by each pumping well for each quarter has been calculated. Estimated reported mass removed in 4lh quarter 2013 is 10.37 lbs. Table 3 below verifies this estimate. Reporting The Report included the following information as required in the QAP: a) Introduction b) Sampling and Monitoring Plan -Description of monitor wells -Description of sampling methodology, equipment and decontamination procedures -Identify all quality assurance samples, e.g. trip blanks, equipment blanks, duplicate samples c) Data Interpretation -Interpretation of groundwater levels, gradients, and flow directions. Interpretations will include a discussion on: 1) A current site groundwater contour map, 2) hydrographs to show groundwater elevation in each monitor well over time, 3) depth to groundwater measured and groundwater elevation from each monitor well summarized in a data table, that includes historic groundwater level data for each well, and 4) an evaluation of the effectiveness of hydraulic capture of all contaminants of concern. -Interpretation of all analytical results for each well, including a discussion on: 1) a current chloroform isoconcentration map with one of the isoconcentration lines showing the 70 pg/L boundary, 2) graphs showing chloroform concentration trends in each well through time and, 3) analytical results for each well summarized in a data table, that includes historic analytical results for each well. -Calculate chloroform mass removed by pumping wells. Calculations would include: 1) total historic chloroform mass removed, 2) total historic chloroform mass removed for each pumping well, 3) total chloroform mass removed for the quarter and, 4) total chloroform mass removed from each pumping well for the quarter. Page 4 d) Conclusions and Recommendations e) Electronic copy of all laboratory results for Chloroform Investigation monitoring conducted during the quarter. f) Copies of DUSA field records, laboratory reports and chain of custody forms. Evaluation of the Chloroform Contaminate Plume and Its Associated Contaminants Bounding Chloroform Plume Groundwater monitoring data for the 4th quarter 2013 monitoring event appeared to show that the chloroform contaminate plume and associated contaminants, carbon tetrachloride, chloromethane, and methylene chloride is bound by up gradient, cross gradient, and down gradient wells that have a chloroform concentration of <70 pg/L (GWQS = 70 pg/L). However, there is a concern about the chloroform concentrations at TW4-29 that continue to exceed the GWQS at 260 pg/L (see Table 1, 27 of 27 below). Therefore, two new wells, TW4-33 and TW4-34, were installed in September of 2013 define the chloroform plume in the vicinity of TW4-29. In the Report it showed that TW4-33 located northwest cross/up gradient of TW4-29 had a chloroform concentration of 126 pg/L and TW4-34 located south and cross gradient of TW4-29 had a chloroform concentration of <1.0 pg/L. The DRC has finished the review of the Contamination Investigation Report TW4-12 and TW4-27 Areas White Mesa Uranium Mill Near Blanding, Utah C'CIR ") submitted to DRC on January 24, 2014. The CIR addressed the chloroform plume in the vicinity of TW4-29 and concluded that there is sufficient wells up, down and cross gradient of TW4-29 to bound the plume. However, although in the The Kriged 4th Quarter, 2013 Water Levels and Estimated Chloroform Capture Zones Chloroform Capture Zones map " ("Map") the groundwater contour lines show that well TW4-30 is downgradient of well TW4-29, because of the extent of the chloroform plume it may continue to migrate through the gap between the well TW4-34 and TW4-30. Therefore, DRC has determined that there needs to be at least one more monitor well to bound the chloroform plume located half way between well TW4-30 and TW4-34 and 200 feet southeast of TW4-29. In a conference call on April 10, 2014 with EFR, EFR agreed to install one more monitor well at the locations describe above. In addition, EFR informed DRC that monitor well TW4-8, that has historically bound the plume east of MW-4, had exceeded the 70 pg/L GWQS in the 1st quarter 2014 monitoring event. In order to bound the plume east MW-4 EFR proposed to install an additional well approximately 250 east of TW4-8. Later that day (April 10, 2014) EFR emailed DRC a map showing the two new well locations. By email DRC agreed with the well locations and EFR will be submitting for DRC review and approval when the two new wells will be drilled and installed, developed, hydraulic tested, (see Attachment 1). Well construction will be documented in an As-Built Report and groundwater sampling well be included in the next monitoring report. Monitor Wells Exceeding Chloroform Concentrations of 70pg/L Eight monitor wells: TW4-1, TW4-2, TW4-7, TW4-10, and TW4-11 increased and TW4-21 and TW4-29 have decreased chloroform concentrations since the 3rd quarter 2013. TW4-33 was sampled for the first time. Page 5 Monitor Wells with Chloroform Concentrations between 1 pg/L and 70ug/L Five monitor wells: TW4-5, TW4-6, TW4-16, TW4-18, and TW4-26 chloroform concentrations of <70pg/L. TW4-6, TW4-16, and TW4-18, appears to have a increasing trend. Pumping Wells Chloroform Concentrations Pumping wells MW-4, MW-26, TW4-4, TW4-19, TW4-20, and TW4-22 exceed chloroform concentrations of 70pg/L. Pumping well TW4-24 had a historic high chloroform concentration of 32.5 pg/L and TW4-25 have non-detectable chloroform concentrations (<1.0 pg/L). Monitor Wells Below the Laboratory Chloroform Detection Limit (<1.0 ug/L) The following monitor wells are below laboratory detection limit for chloroform (<1.0 pg/L): MW-32, TW4-3, TW4-8, TW4-9, TW4-12, TW4-13, TW4-14, TW4-23, TW4-27, TW4-28, TW4-30, TW4-31, TW4-32 and TW4-34. Nitrate, Nitrate + Nitrite ("nitrate") Concentrations Monitor wells TW4-21, TW4-22, TW4-24, and TW4-25 all exceed the nitrate GWQS of 10 mg/l. All of these nitrate exceedances for these wells appear to be a result of the nitrate contaminant plume up-gradient of the chloroform contaminant plume. This nitrate contaminant plume is being addressed under the Nitrate Corrective Action Plan, approved on December 12, 2012. Nitrate concentrations in TW4-12, TW4-26, TW4-27 continue to exceed the GWQS (10 mg/L) and have wells downgradient to with nitrate concentrations <1.0 mg/L Conclusions on Compliance with the Permit and QAP Per the DRC review it appears that the Report complies with Permit and QAP. Therefore a letter will be drafted for the Director Signature, notifying EFR of the review and closing out of the 4th Quarter 2013 Chloroform Monitoring Report for the chloroform contamination investigation. Page 6 References Energy Fuels Resources (USA) Inc., June 7, 2012 White Mesa Uranium Mill, Ground Water Monitoring Quality Assurance Plan (Revision 7.2). Energy Fuels Resources (USA) Inc., November 19, 2013 White Mesa Uranium Mill Chloroform Monitoring Report 3rd Quarter 2013 (July through September 2013). Hydro Geo Chem, Inc., January 23, 2014, Contamination Investigation Report TW4-12 and TW4- 27 Areas White Mesa Mesa Uranium Mill Near Blanding Utah. State of Utah Division of Water Quality Department of Environmental Quality, June 8, 2013, Ground Water Discharge Permit for Denison Mines (USA) Corp. at the White Mesa Mill Facility Near Blanding, Utah. State of Utah Division of Water Quality Department of Environmental Quality, August 23, 1999, White Mesa Uranium Mill: Notice of Violation and Groundwater Corrective Action Order, Docket No UGW-20-01. Attachment 1 Emails Between EFR and DRC 4/24/2014 Proposed Chloroform new well locations - dhenderson@utah gov- State of Utah Mail Click here to enable desktop notifications for State of Utah Ms Mail LaKeWood, UU, US, «U^« http //www enerqvfuels com COMPOSE Inbox (14) Starred Important Sent Mail Drafts Categories Cabinet DOE DOE sent DUSA eDoc tasks This e-mail is intended for the exclusive use the of person(s) mentioned as tl message and any attached files with it are confidential and may contain privi information. If you are not the intended recipient(s) please delete this messa You may not use, distribute print or copy this message if you are not the int Search people.. Edith Barker Kaye Crawford Rusty Lundberg Woodrow Campbell ilene staker Jule Fausto Phillip Goble Thomas Rushing 4352243286 aalder@tsocorp.c. Alder, Anne M Brown, Jaleel - (GT) Bruce Madsen • Dean Henderson <dhenderson@utah gov> Hi Kathy, We agree with the two new well locations for TW4-35 and TW4-36. Please 5 schedule for DRC review and approval on when the two new wells will be drill developement, hydraulic testing, well asbuilt report, and sampled. Thanks K Click here to Reply, RepJy„_to alj, or Forward 5% full Using 1.79 GB of your 30 GB ©2014 Google - Terms of Service • Policy - Program Policies Powered by Privacy La https //mail.google conVmail/u/0/ttnbox'1454cfd1b539485a 1/1 1 K TWN<» .... 5 ?TW4.25 N-01 PIEZ-03 i » TW4- 1 r # m»1 4 8 TW4-I O 4-0 ON 9k, TW4-1 ON 220 TW4-03 ON0 OTW4 28 • TW4 32 TW4-13 ONO 03Z< *afkl4-i MW-04 "W4-07O# rm OTW4-O80TW4 36 TW4-01 O1280 TW4-04 )1360 O TW4-14 O-i V4-27 O OTW4 ND ND 4-23 31 126 TW4526 TW4-29 OTW4-30 ' ND 260 ®TW4 35 TW4-34 * ND PIEZ-04 rti 1 1000 feet ESB1 EXPLANATION ND = nol detected; NS = not sampled TW4-35 proposed perched monitoring well kngcd chloroform isocon and label nand *awn chloroform isocon *^p"^410 perched monitoring well showing concentration in ug/L T>o"t280 tei,,porary perched monitoring well showing concentration in ug/L PIEZ-2 perched piezometer showing * NS concentration in ug/L TW4-32 temporary perched monitoring well #ND installed September, 2013 showing concentration in ug/L NOTE: MW-4. MW-26, TW4-4, TW4-19. and TW4-20 are chloroform pumping wells; TW4-25 is a nitrate pumping well HYDRO GEO CHEM, INC. KRIGED 4th QUARTER, 2013 CHLOROFORM (ug/L) AND PROPOSED PERCHED MONITORING WELLS DATE 04-10-2014 Hy71800Q/nitrateast/CIR/prop_wells14.srf 4/24/2014 State of Utah Mail - Proposed Chloroform new well locations *rt prop_wells14.pdf ^ 126K Dean Henderson <dhenderson@utah.gov> Thu, Apr 10, 2014 at 1:39 PM To: Kathy Weinel <KWeinel@energyfuels.com> Cc: Phillip Goble <pgoble@utah.gov> Hi Kathy, We agree with the two new well locations for TW4-35 and TW4-36. Please submit a plan and a schedule for DRC review and approval on when the two new wells will be drilled and installed, well developement, hydraulic testing, well asbuilt report, and sampled. Thanks Kathy. Dean [Quoted text hidden] https//mail google corrv'rrail/u/0/?ui=2&ik=50c70a6199^^ 2/2 TABLE 1 (1 of 27) Historic Summary Of Monitoring Parameters Up To The 4th Quarter 2013 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Parameter GWQS Carbon Tetrachloride (5 MQ/L) Chloride No GWQS (mg/L) Chloroform Chloromethane <3°"g"-) Methylene Chloride (5 M9/L) Nitrate, Nitrate + Nitrite (10 mg/L) MW-4 (chloroform Dumptngwelt) 1stQ.tr 3/16/05 2nd Qtr 5/25/05 3rdQtr 8/31/05 4th Qtr 12/7/05 1st Qtr 3/9/06 2nd Qtr 6/14/06 3rd Qtr 7/20/06 4th Qtr 11/8/06 1st Qtr 2/28/07 2nd Qtr 6/27/07 3rd Qtr 8/15/07 4th Qtr 10/10/07 1st Qtr 3/28/08 2nd Qtr 6/25/08 3rd Qtr 9/10/08 4th Qtr 10/15/08 1st Qtr 3/4/09 2nd Qtr 6/23/09 3rd Qtr 9/14/09 4th Qtr 12714/09 1st Qtr 2/17/10 2nd Qtr 6/14/10 3rd Qtr 8/6/10 4th Qtr 10/15/10 1st Qtr 2/23/11 2nd Qtr 6/1/11 3rd Qtr 8/17/11 4th Qtr 11/16/11 1st Qtr 1/23/12 2nd Qtr 6/6/12 3rd Qtr 9/4/12 4th Qtr 10/4/12 1st Qtr 2/11/13 2nd Qtr 6/5/13 3rd Qtr 9/3/13 4th Qtr 10/29/13 NA NA <10 <so <50 <50 <50 NA NA NA 2 1 1 6 1 8 1 9 1 7 1 7 1 8 1 8 1 7 1 5 1 3 1 4 1 6 1 2 1 2 1 5 1 4 1 5 1 4 1 1 1 3 1 1 2 1 5 1 1 48 1 31 1 13 5 58 53 49 49 48 50 47 45 47 45 42 42 35 45 37 34 43 44 45 41 38 41 40 35 41 40 41 39 41 41 37 8 44 41 4 40 1 2,900 3,170 3,500 3,000 3,100 3,000 2,820 2,830 2,300 2,000 2,600 2,300 2,400 2,500 1,800 2,100 2,200 1,800 2,000 1,800 1,600 2.100 1,900 1,500 1,700 1,700 1,700 1,600 1,500 1,400 1,500 _1J300 1,670 1,490 1,520 1,410 NA NA <10 <50 <50 <50 <50 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 1 4 NA NA <10 <50 <50 <50 <50 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 6 3 7 1 70 70 60 6 0 1 2 64 6 3 70 6 2 6 2 5 8 6 1 64 59 57 52 5 3 58 40 5 1 4 8 4 9 4 6 49 49 5 1 4 8 4 9 50 4 8 4 8 4 2 4 9 5 3 MW-4A(TW4-A) 1st Qtr 3/16/05 2nd Qtr 5/25/05 3rd Qtr 8/31/05 4th Qtr 12/7/05 1st Qtr 3/9/06 2nd Qtr 6/14/06 3rd Qtr 7/20/05 4th Qtr 11/8/05 1st Qtr 2/28/07 NA NA <10 <50 <50 <50 <50 NA NA NA 24 1 9 3,700 3,740 3,800 3,000 3,700 3,300 3,190 3,370 NA NA <10 <SO <50 <50 <50 <1 0 <1 0 2,500 Well abandonded NA NA <10 <50 <50 <50 <50 <1 0 <1 0 7 1 78 6 9 67 5 8 7 3 1 2 7 1 7 1 NA = not analyzed Shaded indicates concentrations exceeding GWQS Bold and italics indicates the MDL exceeded the GWQS TABLE 1 (2 of 27) Historic Summary Of Monitoring Parameters Up To The 4th Quarter 2013 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Parameter GWQS Carbon Tetrachlonde |5ug/L) Chloride No GWQS (mg/L) Chloroform (70 ug/L) Chloromethane (30 ug/L) Methylene Chloride (5 ug/L) Nitrate, Nitrate + Nitrite (10 mg/L) MW-26 (former TW4-15) Chloroform pumping well 1st Qtr 3/16/05 2nd Qtr 5/25/05 3rd Qtr 8/31/05 4th Qtr 12/7/05 1st Qtr 3/9/06 2nd Qtr 6/14/06 3rd Qtr 7/20/06 4th Qtr 11/8/06 1st Qtr 2/28/07 2nd Qtr 6/27/07 3rd Qtr 8/15/07 4th Qtr 10/10/07 1st Qtr 3/28/08 2nd Qtr 6/25/08 3rd Qtr 9/10/08 4th Qtr 10/15/08 4th Qtr 11/18/09 1 st Qtr 3/4/09 2nd Qtr 6/23/09 3rd Qtr 9/14/09 4th Qtr 12/14/09 1st Qtr 2/17/10 2nd Qtr 6/14/10 3rd Qtr 8/16/10 4th Qtr 10/15/10 1st Qtr 2/23/11 2nd Qtr 5/31/11 3rd Qtr 8/17/11 4th Qtr 11/16/11 '"12/5/11 1st Qtr 2/7/12 2nd Qtr 6/6/12 3rd Qtr 9/4/12 4th Qtr 10/4/12 1st Qtr 2/11/13 2nd Qtr 6/5/13 3rd Qtr 9/3/13 4th Qtr 10/29/13 NA NA <5 0 <50 <50 <50 <50 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA <2 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 <1 <1 <1 0 <1 0 <1 NA NA NA NA 55 52 52 65 54 56 49 57 57 49 57 44 64 49 48 46 60 57 40 49 65 57 88 58 69 98 73 73 68 81 9 77 9 60 5 72 3 NA 310 442 960 1,000 1,100 830 2,170 262 570 300 1,400 2,000 930 1,300 630 1,700 950 410 850 1,100 730 1,600 2,200 970 450 1,800 720 _1J300 2,400~ 3,000 3,100 1,200 2,120 4,030 2,940 1,410 NA NA 54 <50 <50 <50 <50 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA <2 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 <1 <1 <1 0 <1 0 <1 NA NA <5 0 <50 <50 <50 <50 NA 26 5.5 13 36 14 40 53 24 100 51 12 30 _40 19 21 6.5 36 1 3 7.2 29 16 21 31 4 9.34 52.4 33 2 4 03 NA 0 3 02 02 0 3 02 02 1 4 03 06 04 1 06 0 1 06 02 0 1 04 02 0 1 23 0 2 6 8 06 07 05 04 0 9 20 1 7 2 5 26 1 8 23 2 1 1 2 1 4 (1) VOCs were resampled because laboratory missed holding time NA = not analyzed Shaded indicates concentrations exceeding GWQS Bold and italics indicates the MDL exceeded the GWQS TABLE 1 (3 of 27) Historic Summary Of Monitoring Parameters Up To The 4th Quarter 2013 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Parameter GWQS Carbon Tetrachloride Chloride (5 ug/L) | No GWQS (mg/L) Chloroform (7Q pg/L) Chloromethane (3Q pg/L) Methylene Chloride (5 pg/M Nitrate, Nitrate + Nitrite (10 mg/L) MW-32 (former TW4-17} 1st Qtr 3/16/05 2nd Qtr 5/25/05 3rd Qtr 8/31/05 4th Qtr 12/7/05 1st Qtr 3/9/06 2nd Qtr 6/14/06 3rd Qtr 7/20/06 4th Qtr 11/8/06 1st Qtr 2/28/07 2nd Qtr 6/27/07 3rd Qtr 8/15/07 4th Qtr 10/10/07 1 st Qtr 3/28/08 2nd Qtr 6/25/08 3rd Qtr 9/10/08 4th Qtr 10/15/08 1st Qtr 3/4/09 2nd Qtr 6/23/09 3rd Qtr 9/14/09 4th Qtr 12/16/09 1st Qtr 2/17/10 2nd Qtr 6/14/10 3rd Qtr 8/16/10 4th Qtr 10/15/10 1st Qtr 2/23/11 2nd Qtr 5/25/11 3rd Qtr 8/16/11 4th Qtr 11/16/11 "'12/7/11 1st Qtr 1/18/12 2nd Qtr 6/22/12 3rd Qtr 9/5/12 4th Qtr 10/10/12 1st Qtr 2/11/13 2nd Qtr 6/18/13 3rd Qtr 9/3/13 4th Qtr 10/29/13 NA NA <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA NA NA 33 32 30 32 31 32 32 31 32 31 29 30 26 30 31 33 35 38 32 28 24 40 31 33 32 21 32 33 35 34 3 34 9 33 35 7 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA NA <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 32 3 5 1 1 5 NA NA <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <0 1 <0 1 <0 1 <0 1 <0 1 <0 1 <1 0 < 1 <1 0 <1 0 <1 0 <1 0 < 1 <1 0 <1 0 <0 05 < 1 <0 1 <0 1 <0 1 <0 1 <0 1 <0 1 <0 1 <0 1 <0 1 <0 1 <0 1 <0 1 <0 1 <0 1 <0 1 <0 1 <0 1 <0 1 <0 1 (1) VOCs were resampled because laboratory missed holding time NA = not analyzed Shaded indicates concentrations exceeding GWQS TABLE 1 (4 of 27) Historic Summary Of Monitoring Parameters Up To The 4th Quarter 2013 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Parameter GWQS Carbon Tetrachloride (5 MQ/L) Chloride No GWQS (mg/L) Chloroform (70 ug/L) Chloromethane (30 ug/L) Methylene Chloride (5 Mg/L) Nitrate, Nitrate + Nitrite (10 mg/L) TW4-1 1st Qtr 3/16/05 2nd Qtr 5/25/05 3rd Qtr 8/31/05 4th Qtr 12/7/05 1st Qtr 3/9/06 2nd Qtr 6/14/06 3rd Qtr 7/20/06 4th Qtr 11/8/06 1st Qtr 2/28/07 2nd Qtr 6/27/07 3rd Qtr 8/15/07 4th Qtr 10/10/07 1st Qtr 3/28/08 2nd Qtr 6/25/08 3rd Qtr 9/10/08 4th Qtr 10/15/08 1st Qtr 3/11/09 2nd Qtr 6/23/09 3rd Qtr 9/14/09 4th Qtr 12/29/09 1st Qtr 3/3/10 2nd Qtr 6/14/10 3rd Qtr 8/18/10 4th Qtr 10/15/10 1st Qtr 2/24/11 2nd Qtr 6/1/11 3rd Qtr 8/18/11 4th Qtr 11/29/11 1st Qtr 1/24/12 2nd Qtr 6/14/12 3rd Qtr 9/28/12 4th Qtr 10/4/12 1st Qtr 2/13/13 2nd Qtr 6/19/13 3rd Qtr 9/3/13 4th Qtr 11/14/14 NA NA <10 <50 <50 <50 <50 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 1 4 1 2 1 4 1 3 1 3 1 3 1 1 1 3 1 3 1 1 1 1 2 1 3 66 NA NA NA 52 49 48 51 47 47 45 43 43 39 39 35 41 37 37 36 41 35 40 35 40 41 35 36 40 38 42 39 40 37 6 39 1 37 6 36 5 2,700 3,080 2,900 2,400 2,700 2,200 2,840 2,260 1,900 1,900 2,300 2,000 2,000 1,900 1.700 1J00 1,700 1,500 1,700 1,400 1,300 1,600 1,600 1,500 1,300 1.200 1,300 1,500 1,300 1,000 1,000 V go 1,320 1,100 1,150 1,280 NA NA <10 <50 <50 <50 <50 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA NA <10 <50 <50 <50 <50 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 9 1 10.6 98 97 94 96 92 8 9 9 84 7 76 8 68 8 15 9 3 7 5 6 9 7 3 68 7 1 6 8 6 7^ 66 66 66 68 66 68 7 1 50 6 5 7 0 69 7 1 7 1 NA = not analyzed Shaded indicates concentrations exceeding GWQS Bold and italics indicates the MDL exceeded the GWQS TABLE 1 (5 of 27) Historic Summary Of Monitoring Parameters Up To The 4th Quarter 2013 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Parameter GWQS Carbon Tetrachloride (5 pg/L) Chloride No GWQS (mg/L) Chloroform (70M9/L) Chloromethane (30 M9/L) Methylene Chloride (5 M9/L) Nitrate, Nitrate + Nitrite (10 mg/L) TW4-2 1st Qtr 3/16/05 2nd Qtr 5/25/05 3rd Qtr 8/31/05 4th Qtr 12/7/05 1st Qtr 3/9/06 2nd Qtr 6/14/06 3rd Qtr 7/20/06 4th Qtr 11/8/06 1st Qtr 2/28/07 2nd Qtr 6/27/07 3rd Qtr 8/15/07 4th Qtr 10/10/07 1st Qtr 3/28/08 2nd Qtr 6/25/08 3rd Qtr 9/10/08 4th Qtr 10/15/08 4th Qtr 11/18/09 1st Qtr 3/11/09 2nd Qtr 6/23/09 3rd Qtr 9/14/09 4th Qtr 12/29/09 1st Qtr 3/3/10 2nd Qtr 6/14/10 3rd Qtr 8/18/10 4th Qtr 10/15/10 1st Qtr 2/24/11 2nd Qtr 6/2/11 3rd Qtr 8/17/11 4th Qtr 11/29/11 1st Qtr 1/24/12 2nd Qtr 6/14/12 3rd Qtr 9/28/12 4th Qtr 10/4/12 1st Qtr 2/13/13 2nd Qtr 6/19/13 3rd Qtr 9/3/13 4th Qtr 11/14/14 NA NA <10 <50 <50 <50 <50 NA 2 3 1 8 2 5 22 2 1 23 22 24 24 22 2 2 2 2 26 2 5 2 1 24 22 1 6 2 8 2 2 1 1 8 2 5 17 2 65 2 41 3 15 NA NA NA NA 56 56 56 54 55 54 50 49 51 48 46 42 47 46 44 43 46 42 43 43 41 46 42 48 49 49 52 76 49 46 46 9 44 9 43 9 3,700 3,750 3,900 _ 3,500 3,800 3,200 4,120 3^420 NA 2,300 3,000 340 (?) 3,200 3,300 3,100 2,800 _ 3,200 3,100 2,800 3,000 1,600 2,600 3,300 3,300 3,000 3.100 3,000 2,400 3,900 2,500 2,500 2,900 3,100 3,580 3,110 3,480 3,740 NA NA <10 <50 <50 <50 <50 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA <2 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA NA <10 <50 <50 <50 <50 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA <2 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA 7 7 8 6 80 78 75 7 1 74 76 7 3 7 73 69 6 9 74 7 1 80 6 5 64 66 64 6 8 87 66 6 5 70 68 60 7 0 7 1 77 40 76 8 1 7 5 9 3 84 NA = not analyzed Shaded indicates concentrations exceeding GWQS Bold and italics indicates the MDL exceeded the GWQS TABLE 1 (6 of 27) Historic Summary Of Monitoring Parameters Up To The 4th Quarter 2013 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Parameter GWQS Carbon Tetrachloride 15 Mfl/L) Chloride No GWQS (mg/L) Chloroform (70 ug/L) Chloromethane (30 H9'1-) Methylene Chloride (5 Mg/L) Nitrate, Nitrate + Nitrite (10 mg/L) TW4-3 1st Qtr 3/16/05 2nd Qtr 5/25/05 3rd Qtr 8/31/05 4th Qtr 12/7/05 1st Qtr 3/9/06 2nd Qtr 6/14/06 3rd Qtr 7/20/06 4th Qtr 11/8/06 1st Qtr 2/28/07 2nd Qtr 6/27/07 3rd Qtr 8/15/07 4th Qtr 10/10/07 1st Qtr 3/28/08 2nd Qtr 6/25/08 3rd Qtr 9/10/08 4th Qtr 10/15/08 1st Qtr 3/4/09 2nd Qtr 6/23/09 3rd Qtr 9/14/09 4th Qtr 12/29/09 1st Qtr 2/23/10 2nd Qtr 6/14/10 3rd Qtr 8/10/10 4th Qtr 10/15/10 1st Qtr 2/15/11 2nd Qtr 5/25/11 3rd Qtr 8/16/11 4th Qtr 11/14/11 1st Qtr 1/17/12 2nd Qtr 5/31/12 3rd Qtr 8/29/12 4th Qtr 10/3/12 1st Qtr 2/7/13 2nd Qtr 6/29/13 3rd Qtr 9/3/13 4th Qtr 11/6/13 NA NA <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA NA NA 26 26 26 26 23 22 23 24 27 21 19 19 22 21 20 21 22 23 24 22 26 23 23 23 23 21 24 25 25 23 7 23 8 25 24 1 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA NA <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 64 2 3 1 6 22 NA NA <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 3 5 3 7' 3 5 3 3 3 3 7 1 29 1 5 3 1 3 3 3 1 28 2 8 2 9 27 26 2 5 29 2 8 2 6 28 30 3 1 33 35 37 4 0 4 4 7 1 4 4 4 9 4 8 5 1 58 4 9 59 NA = not analyzed Shaded indicates concentrations exceeding GWQS TABLE 1 (7 of 27) Historic Summary Of Monitoring Parameters Up To The 4th Quarter 2013 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Parameter GWQS Carbon Tetrachloride 15 pg/D Chloride No GWQS (mg/L) Chloroform 170 pg/L) Chloromethane (30 pg/L) Methylene Chloride (5 pg/L) Nitrate, Nitrate + Nitrite (10 mg/L) TW4-4 (chioroi pumping well) 1st Qtr 3/16/05 2nd Qtr 5/25/05 3rd Qtr 8/31/05 4th Qtr 12/7/05 1 st Qtr 3/9/06 2nd Qtr 6/14/06 3rd Qtr 7/20/06 4th Qtr 11/8/06 1st Qtr 2/28/07 2nd Qtr 6/27/07 3rd Qtr 8/15/07 4th Qtr 10/10/07 1 st Qtr 3/28/08 2nd Qtr 6/25/08 3rd Qtr 9/10/08 4th Qtr 10/15/08 4th Qtr 11/18/09 1 st Qtr 3/4/09 2nd Qtr 6/23/09 3rd Qtr 9/14/09 4th Qtr 12/29/09 1st Qtr 2/17/10 2nd Qtr 6/14/10 3rd Qtr 8/10/10 4th Qtr 10/15/10 1st Qtr 2/23/11 2nd Qtr 6/1/11 3rd Qtr 8/17/11 4th Qtr 11/16/11 1st Qtr 1/23/12 2nd Qtr 6/6/12 3rd Qtr 9/4/12 4th Qtr 10/3/12 1st Qtr 2/11/13 2nd Qtr 6/29/13 3rd Qtr 9/3/13 4th Qtr 10/3/13 NA NA <10 <50 <50 <50 <50 NA <2 0 <1 0 <1 0 <1 0 1 2 1 1 <1 0 1 2 5.3 1 7 1 5 1 7 1 5 1 5 1 6 1 5 1 4 1 2 1 2 1 1 1 1 1 1 2 1 3 1 3 1 4 1 2 NA NA NA NA 54 51 48 50 49 49 47 45 47 43 42 39 44 37 34 39 41 48 35 36 38 41 35 40 39 38 43 39 38 39 39 6 38 8 43 9 NA 3,100 2,400 3,200 2,800 2,900 2,600 2,850 2,670 2,200 2,400 2,700 2,500 2,800 2,500 2,200 2,500 2,200 1,800 2,000 950 " 1,700 1,700 2,100 1,700 1,800 1,700 1,500 1J500 1,200 1,500 1,600 1,400 1,460 1,330 1,380 1,360 NA NA <10 <50 <50 <50 <50 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA <2 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA NA <10 <50 <50 <50 <50 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA <2 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA 10 0 11.3 99 10.2 95 86 97 10.1 90 94 95 9 5 9 2 10.8 8 8 10.1 10 2 8 2 8 4 76 6 6 7 6 73 7 1 7 0 7 0 66 7 0 7 1 7 1 7 1 7 0 74 6 3 72 78 NA = not analyzed Shaded indicates concentrations exceeding GWQS Bold and italics indicates the MDL exceeded the GWQS TABLE 1 (8 of 27) Historic Summary Of Monitoring Parameters Up To The 4th Quarter 2013 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Parameter GWQS Carbon Tetrachloride (5 ug'L) Chloride No GWQS (mg/L) Chloroform (70 M^L) Chloromethane (30 pg/L) Methylene Chloride (5H9/L) Nitrate, Nitrate + Nitrite (10 mg/L) TW4-5 1st Qtr 3/16/05 2nd Qtr 5/25/05 3rd Qtr 8/31/05 4th Qtr 12/7/05 1st Qtr 3/9/06 2nd Qtr 6/14/06 3rd Qtr 7/20/06 4th Qtr 11/8/06 1st Qtr 2/28/07 2nd Qtr 6/27/07 3rd Qtr 8/15/07 4th Qtr 10/10/07 1 st Qtr 3/28/08 2nd Qtr 6/25/08 3rd Qtr 9/10/08 4th Qtr 10/15/08 1st Qtr 3/4/09 2nd Qtr 6/23/09 3rd Qtr 9/14/09 4th Qtr 12/29/09 1st Qtr 2/25/10 2nd Qtr 6/14/10 3rd Qtr 8/11/10 4th Qtr 10/15/10 1 st Qtr 2/22/11 2nd Qtr 5/26/11 3rd Qtr 8/7/11 4th Qtr 11/16/11 11112/7/11 1st Qtr 1/18/12 2nd Qtr 6/6/12 3rd Qtr 9/11/12 4th Qtr 10/3/12 1st Qtr 2/13/13 2nd Qtr 6/13/13 3rd Qtr 9/5/13 4th Qtr 11/13/13 NA NA <2 5 <2 5 <2 5 <2 5 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA NA NA 56 52 51 54 55 57 45 38 39 36 37 34 37 34 37 48 41 43 28 38 41 34 35 37 30 22 39 37 38 34 3 36 5 39 1 41 1 120 113 82 63 66 51 53 7 47 1 35 26 9 2 94 11 93 11 10 12 13 12 8 5 13 12 12 11 10 9 10 7 9 7 6 84 12 8 108 11 2 11 6 14 4 NA NA <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 58 25 3 1 3 1 NA NA <2 5 <2 5 <2 5 <2 5 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 4 9 37 60 60 60 59 67 29 78 7 0 77 82 74 87 79 9 3 7 9 7 5 8 3 7 5 68 7 1 70 72 7 0 72 7 5 60 58 80 8 1 77 82 107 78 78 (1) VOCs were resampled because laboratory missed holding time NA = not analyzed Shaded indicates concentrations exceeding GWQS TABLE 1 (9 of 27) Historic Summary Of Monitoring Parameters Up To The 4th Quarter 2013 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Parameter GWQS Carbon Tetrachloride (5 ug'L) Chloride No GWQS (mg/L) Chloroform (70 M9/L) Chloromethane (30 ^'D Methylene Chloride (5 ug/L) Nitrate, Nitrate + Nitrite (10 mg/L) TW4-6 1st Qtr 3/16/05 2nd Qtr 5/25/05 3rd Qtr 8/31/05 4th Qtr 12/7/05 1st Qtr 3/9/06 2nd Qtr 6/14/06 3rd Qtr 7/20/06 4th Qtr 11/8/06 1st Qtr 2/28/07 2nd Qtr 6/27/07 3rd Qtr 8/15/07 4th Qtr 10/10/07 1st Qtr 3/28/08 2nd Qtr 6/25/08 3rd Qtr 9/10/08 4th Qtr 10/15/08 1st Qtr 3/11/09 2nd Qtr 6/23/09 3rd Qtr 9/14/09 4th Qtr 12/29/09 1st Qtr 2/25/10 2nd Qtr 6/14/10 3rd Qtr 8/11/10 4th Qtr 10/15/10 1st Qtr 2/23/11 2nd Qtr 5/26/11 3rd Qtr 8/17/11 4th Qtr 11/16/11 12/7/11 12111/16/11 1st Qtr 1/18/12 2nd Qtr 6/13/12 3rd Qtr 9/11/12 4th Qtr 10/3/12 1st Qtr 2/13/13 2nd Qtr 6/13/13 3rd Qtr 9/5/13 4th Qtr 11/13/13 NA NA <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA NA NA <1 0 32 31 30 37 65 32 38 36 35 33 35 35 33 35 37 37 41 45 33 31 41 40 42 39 36 33 38 40 21 41 40 4 37 9 40 6' 40 2 25 10 17 31 19 11 42 8 46 11 18 18 52 24 39 37 81 120 280 250 1000 590 630 420 47 96 16 21 50 38 47 69 9 6 89 4 86 5 93 5 51 NA NA <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 28 1 3 NA NA <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 02 04 0 8 0 9 1 2 1 0 06 1 4 1 8 06 07 0 8 1 1 09 1 1 1 0 22 27 5 0 6 1 1 8 2 5 39 4 3 07 03 0 3 08 08 07 0 2 0 1 02 02 02 02 1 5 (1) VOCs were resampled because laboratory missed holding time (2) Results of the TW4-70 the duplicate sample for TW4-6 NA = not analyzed Shaded indicates concentrations exceeding GWQS TABLE 1 (10 of 27) Historic Summary Of Monitoring Parameters Up To The 4th Quarter 2013 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Parameter GWQS Carbon Tetrachloride 15 ua/L) Chloride No GWQS (mg/L) Chloroform (70 ug/L) Chloromethane (30 M9/L) Methylene Chloride 15 ug/L) Nitrate, Nitrate + Nitrite (10 mg/L) TW4-7 1st Qtr 3/16/05 2nd Qtr 5/25/05 3rd Qtr 8/31/05 4th Qtr 12/7/05 1st Qtr 3/9/06 2nd Qtr 6/14/06 3rd Qtr 7/20/06 4th Qtr 11/8/06 1st Qtr 2/28/07 2nd Qtr 6/27/07 3rd Qtr 8/15/07 4th Qtr 10/10/07 1st Qtr 3/28/08 2nd Qtr 6/25/08 3rd Qtr 9/10/08 4th Qtr 10/15/08 4th Qtr 11/18/09 1st Qtr 3/11/09 2nd Qtr 6/23/09 3rd Qtr 9/14/09 4th Qtr 12/29/09 1st Qtr 3/3/10 2nd Qtr 6/14/10 3rd Qtr 8/11/10 4th Qtr 10/15/10 1st Qtr 2/23/11 2nd Qtr 6/1/11 3rd Qtr 8/18/11 4th Qtr 11/29/11 1st Qtr 1/19/12 2nd Qtr 6/14/12 3rd Qtr 9/13/12 4th Qtr 10/4/12 1st Qtr 2/13/13 2nd Qtr 6/18/13 3rd Qtr 9/12/13 4th Qtr 11/14/13 NA NA <10 <50 <SO <50 <50 NA <2 0 <1 0 <1 0 <1 0 <1 0 1 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA NA NA 1 5 1 1 1 5 1 4 1 2 1 3 1 3 1 4 1 2 1 NA 52 48 47 51 49 47 45 44 45 43 43 35 40 35 37 37 37 35 31 36 38 45 35 37 37 37 41 40 41 37 7 39 3 36 4 37 2 NA 3,100 2,700 3,100 2,500 1,900 2,200 2,140 2,160 1,830 2,600 2,300 1,900 2,200 1,800 1,600 2,500 1,800 1,400 1,500 1,300 1,200 1,100 1,500 1,100 1,300 1,200 1,200 1,000 1,000 790 870 940 940 953 1,040 NA NA <10 <50 <50 <50 <50 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA <2 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA NA <10 <50 <50 <50 <50 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA <2 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA 5 2; 54 52 53 1 4 5 47 4 6 6 5 1 47 47 42 4 8 4 16 4 01 37 38 4 1 42 38 39 39 4 3 6 40 4 1 38 39 4 0 3 8 38 3 5 4 0 4 2 4 1 NA = not analyzed Shaded indicates concentrations exceeding GWQS Bold and italics indicates the MDL exceeded the GWQS TABLE 1 (11 of 27) Historic Summary Of Monitoring Parameters Up To The 4th Quarter 2013 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Parameter GWQS Carbon Tetrachloride (5 M9/L) Chloride No GWQS (mg/L) Chloroform (70 M9/L) Chloromethane Methylene Chloride (5 M9/L) Nitrate, Nitrate + Nitrite (10 mg/L) TW4-8 1st Qtr 3/16/05 2nd Qtr 5/25/05 3rd Qtr 8/31/05 4th Qtr 12/7/05 1st Qtr 3/9/06 2nd Qtr 6/14/06 3rd Qtr 7/20/06 4th Qtr 11/8/06 1st Qtr 2/28/07 2nd Qtr 6/27/07 3rd Qtr 8/15/07 4th Qtr 10/10/07 1st Qtr 3/28/08 2nd Qtr 6/25/08 3rd Qtr 9/10/08 4th Qtr 10/15/08 1st Qtr 3/4/09 2nd Qtr 6/23/09 3rd Qtr 9/14/09 4th Qtr 12/17/09 1st Qtr 2/24/10 2nd Qtr 6/14/10 3rd Qtr 8/18/10 4th Qtr 10/15/10 1st Qtr 2/16/11 2nd Qtr 5/25/11 3rd Qtr 8/16/11 4th Qtr 11/16/11 (,)12/7/11 1st Qtr 1/18/12 2nd Qtr 5/13/12 3rd Qtr 8/29/12 4th Qtr 10/3/12 1st Qtr 2/7/13 2nd Qtr 5/30/13 3rd Qtr 9/5/13 4th Qtr 11/7/13 NA NA <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA NA NA 41 39 37 39 40 39 42 42 43 46 45 39 44 42 44 44 51 57 42 45 46 52 45 46 45 45 44 48 47 46 6 45 5 47 5 46 1 holding time <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 10 1 3 1 25 2 5 1 5 35 NA NA <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 1 7 2 1 1 0 NA NA NA <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <0 1 <1 0 <1 0 <1 0 < 1 <1 0 <1 0 <0 05 <0 05 <0 1 <0 1 <0 1 <0 1 <0 1 <0 1 <0 1 0 1 <0 1 02 0 3 0 1 07 02 0 5 0 1 0 1 0 1 02 03 02 0 1 <0 1 04 <0 1 0 1 <0 1 (1) VOCs were resampled because laboratory missed NA = not analyzed Shaded indicates concentrations exceeding GWQS TABLE 1 (12 of 27) Historic Summary Of Monitoring Parameters Up To The 4th Quarter 2013 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Parameter GWQS Carbon Tetrachloride (5 ug/L) Chloride No GWQS (mg/L) Chloroform (7Q ug/L) Chloromethane (30 pg/L) Methylene Chloride (5 pg/L) Nitrate, Nitrate + Nitrite (10 mg/L) TW4-9 1st Qtr 3/16/05 2nd Qtr 5/25/05 3rd Qtr 8/31/05 4th Qtr 12/7/05 1st Qtr 3/9/06 2nd Qtr 6/14/06 3rd Qtr 7/20/06 4th Qtr 11/8/06 1st Qtr 2/28/07 2nd Qtr 6/27/07 3rd Qtr 8/15/07 4th Qtr 10/10/07 1st Qtr 3/28/08 2nd Qtr 6/25/08 3rd Qtr 9/10/08 4th Qtr 10/15/08 1st Qtr 3/4/09 2nd Qtr 6/23/09 3rd Qtr 9/14/09 4th Qtr 12/17/09 1st Qtr 2/23/10 2nd Qtr 6/14/10 3rd Qtr 8/13/10 4th Qtr 10/15/10 1st Qtr 2/17/11 2nd Qtr 5/25/11 3rd Qtr 8/16/11 4th Qtr 11/16/11 (1) 12/7/11 1st Qtr 1/18/12 2nd Qtr 5/31/12 3rd Qtr 8/30/12 4th Qtr 10/3/12 1st Qtr 2/7/13 2nd Qtr 5/30/13 3rd Qtr 9/5/13 4th Qtr 11/7/13 NA NA <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA NA NA 42 38 39 41 44 44 42 38 40 35 35 28 58 30 30 30 37 47 33 40 34 41 38 21 38 28 23 22 21 20 6 21 4 22 7 23 6 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 38 1 2 19 21 9 5 8 7 1 3 1 NA NA <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 29 26 27 NA NA <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 1 3 1 3 1 3 1 3 1 5 1 5 09 07 06 1 3 1 8 2 2 1 23 2 79 1 99 2 5 23 2 5 1 7 1 4 1 5 1 2 1 1 3 34 4 2 3 2 3 4 0 39 38 4 5 4 5 40 49 (1) VOCs were resampled because laboratory missed holding time NA = not analyzed Shaded indicates concentrations exceeding GWQS TABLE 1 (13 of 27) Historic Summary Of Monitoring Parameters Up To The 4th Quarter 2013 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Parameter GWQS Carbon Tetrachloride I5M9/L) No Chloride GWQS (mg/L) Chloroform (70 M9/L) Chloromethane (30 ug/L) Methylene Chloride (5 pg/L) Nitrate, Nitrate + Nitrite (10 mg/L) TW4-10 1st Qtr 3/16/05 2nd Qtr 5/25/05 3rd Qtr 8/31/05 4th Qtr 12/7/05 1 st Qtr 3/9/06 2nd Qtr 6/14/06 3rd Qtr 7/20/06 4th Qtr 11/8/06 1st Qtr 2/28/07 2nd Qtr 6/27/07 3rd Qtr 8/15/07 4th Qtr 10/10/07 1st Qtr 3/28/08 2nd Qtr 6/25/08 3rd Qtr 9/10/08 4th Qtr 10/15/08 4th Qtr 11/18/09 1st Qtr 3/11/09 2nd Qtr 6/23/09 3rd Qtr 9/14/09 4th Qtr 12/22/09 1st Qtr 3/3/10 2nd Qtr 6/14/10 3rd Qtr 8/12/10 4th Qtr 10/15/10 1st Qtr 2/23/11 2nd Qtr 6/14/11 3rd Qtr 8/17/11 4th Qtr 11/16/11 1st Qtr 1/19/12 2nd Qtr 6/14/11 3rd Qtr 9/12/12 4th Qtr 10/3/12 1st Qtr 2/13/13 2nd Qtr 6/13/13 3rd Qtr 9/12/13 4th Qtr 11/14/13 NA NA <2 5 <2 5 <5 0 <5 0 <5 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA <2 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA NA NA NA 52 50 54 61 58 2 54 59 59 55 58 51 61 64 62 51 51 48 42 38 52 32 42 41 45 40 46 44 45 49 1 51 5 67 9 70 9 NA 140 62 4 110 300 190 300 504 452 500 350 660 470 620 720 660 1,200 1,100 1,200 910 300 460 220 100 1100 620 280 180 110 76 79 130 140 154 486 1126 1380 NA NA <2 5 <5 0 <5 0 <5 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA <2 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 62 1 6 NA NA <2 5 <2 5 <5 0 <5 0 <5 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA <2 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <t 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA 1 6 0 8 1 1 3 3 2 4 3 5 6 8 57 73 5 1 7 3 67 7 3 99 9 23 10.5 11.6 98 8 1 3 8 50 1 6 0 8 11.0 90 33 1 9 1 1 09 0 1 0 1 6 1 2 56 13 0 160 NA = not analyzed Shaded indicates concentrations exceeding GWQS TABLE 1 (14 of 27) Historic Summary Of Monitoring Parameters Up To The 4th Quarter 2013 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Parameter GWQS Carbon Tetrachloride (5 ug/L) Chloride No GWQS (mg/L) Chloroform (70 jig/L) Chloromethane (3Q pg/n Methylene Chloride (5 pg/L) Nitrate, Nitrate + Nitrite (10 mg/L) TW4-11 1st Qtr 3/16/05 2nd Qtr 5/25/05 3rd Qtr 8/31/05 4th Qtr 12/7/05 1st Qtr 3/9/06 2nd Qtr 6/14/06 3rd Qtr 7/20/06 4th Qtr 11/8/06 1st Qtr 2/28/07 2nd Qtr 6/27/07 3rd Qtr 8/15/07 4th Qtr 10/10/07 1st Qtr 3/28/08 2nd Qtr 6/25/08 3rd Qtr 9/10/08 4th Qtr 10/15/08 4th Qtr 11/18/09 1st Qtr 3/11/09 2nd Qtr 6/23/09 3rd Qtr 9/14/09 4th Qtr 12/29/09 1st Qtr 3/3/10 2nd Qtr 6/14/10 3rd Qtr 8/12/10 4th Qtr 10/15/10 1st Qtr 2/23/11 2nd Qtr 6/1/11 3rd Qtr 8/17/11 4th Qtr 11/16/11 1st Qtr 1/24/12 2nd Qtr 6/13/12 3rd Qtr 9/13/12 4th Qtr 10/3/12 1st Qtr 2/13/13 2nd Qtr 6/18/13 3rd Qtr 9/12/13 4th Qtr 11/13/13 NA NA <10 <100 <50 <50 <50 <1 0 <1 0 <1 0 NA <2 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA NA NA 1 7 1 3 1 6 1 7 1 6 NA 3 23 58 56 56 55 55 54 53 53 53 63 46 42 47 49 44 49 46 42 40 43 49 46 49 48 46 43 52 49 50 47 3 49 3 46 6 46 7 NA 4,400 3,590 4,400 4,400 4,400 4,300 4,080 ^660 3,600 3,800 4,500 4,400 340 640 900 1,000 1,000 980 1,000 860 820 820 800 720 1,000 930 820 1500 610 660 740 730 867 788 865 874 NA NA <10 <100 <50 <50 <50 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA <2 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 27 NA NA <10 <100 <50 <50 <50 <1 0 <1 0 <1 0 <1 0 <1 0 NA <2 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 1 3 1 6 1 2 NA 87 10.3 94 94 92 10 0 100 100 10.1 10.6 102 9 8 77 7 3 79 9 5 7 3 68 70 66 6 8 6 9 67 64 6 5 7 3 7 1 7 1 68 67 30 70 68 74 78 8 0 NA = not analyzed Bold and italics indicates the MDL exceeded the GWQS Bold and italics indicates the MDL exceeded the GWQS TABLE 1 (15 of 27) Historic Summary Of Monitoring Parameters Up To The 4th Quarter 2013 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Parameter GWQS Carbon Tetrachloride (Sug/U Chloride No GWQS (mg/L) Chloroform (70 ug/L) Chloromethane (30 ug/L) Methylene Chloride (5 ug/L) Nitrate, Nitrate + Nitrite (10 mg/L) TW4-12 1st Qtr 3/16/05 2nd Qtr 5/25/05 3rd Qtr 8/31/05 4th Qtr 12/7/05 1st Qtr 3/9/06 2nd Qtr 6/14/06 3rd Qtr 7/20/06 4th Qtr 11/8/06 1st Qtr 2/28/07 2nd Qtr 6/27/07 3rd Qtr 8/15/07 4th Qtr 10/10/07 1st Qtr 3/28/08 2nd Qtr 6/25/08 3rd Qtr 9/10/08 4th Qtr 10/15/08 1st Qtr 3/11/09 2nd Qtr 6/23/09 3rd Qtr 9/14/09 4th Qtr 12/16/09 1st Qtr 2/23/10 ' 2nd Qtr 6/14/10 3rd Qtr 8/10/10 4th Qtr 10/15/10 1 st Qtr 2/15/11 2nd Qtr 5/25/11 3rd Qtr 8/16/11 4th Qtr 11/15/11 1st Qtr 1/17/12 2nd Qtr 5/31/12 3rd Qtr 8/29/12 4th Qtr 10/3/12 1st Qtr 2/13/13 2nd Qtr 5/29/13 3rd Qtr 8/29/13 4th Qtr 11/6/13 NA NA <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA NA NA 19 19 16 16 16 16 18 29 16 16 19 18 22 23 22 22 23 22 29 35 31 31 32 31 30 28 34 39 39 36 7 38 6 41 7 41 4 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA NA <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 58 1 0 26 1 4 1 4 NA NA <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 1 4 1 6 1 5 1 4 1 3 1 4 1 4 1 4 1 5 1 5 1 4 1 4 1 6 27 27 25 24 38 5 1 36 4 0 11 0 9 0 80 65 7 0 6 8 8 0 7 7 100 13.0 13.0 12.6 14 2 17.4 164 NA = not analyzed Shaded indicates concentrations exceeding GWQS TABLE 1 (16 of 27) Historic Summary Of Monitoring Parameters Up To The 4th Quarter 2013 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Parameter GWQS Carbon Tetrachloride (5 MQ'L) Chloride No GWQS (mg/L) Chloroform (70 pg/L) Chloromethane (30 ug/L) Methylene Chloride (5 Mg/L) Nitrate, Nitrate + Nitrite (10 mg/L) TW4-13 1st Qtr 3/16/05 2nd Qtr 5/25/05 3rd Qtr 8/31/05 4th Qtr 12/7/05 1st Qtr 3/9/06 2nd Qtr 6/14/06 3rd Qtr 7/20/06 4th Qtr 11/8/06 1st Qtr 2/28/07 2nd Qtr 6/27/07 3rd Qtr 8/15/07 4th Qtr 10/10/07 1st Qtr 3/28/08 2nd Qtr 6/25/08 3rd Qtr 9/10/08 4th Qtr 10/15/08 1st Qtr 3/4/09 2nd Qtr 6/23/09 3rd Qtr 9/14/09 4th Qtr 12/16/09 1st Qtr 2/24/10 2nd Qtr 6/14/10 3rd Qtr 8/10/10 4th Qtr 10/15/10 1st Qtr 2/15/11 2nd Qtr 5/25/11 3rd Qtr 8/16/11 4th Qtr 11/15/11 1st Qtr 1/17/12 2nd Qtr 5/31/12 3rd Qtr 8/29/12 4th Qtr 10/3/12 1st Qtr 2/13/13 2nd Qtr 5/29/13 3rd Qtr 8/29/13 4th Qtr 11/6/13 NA NA <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA NA NA 69 67 66 65 33 59 59 58 58 54 58 50 58 58 57 63 60 53 53 55 55 60 56 60 54 55 59 60 60 59 3 56 63 5 58 5 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA NA <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 3 1 1 7 1 4 NA NA <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 4 2 4 3 46 43 42 49 4 3 08 40 4 6 44 4 1 38 42 43 46 37 1 2 47 4 1 43 52 56 58 5 5 64 52 5 9 5 5 60 62 59 63 68 72 65 NA = not analyzed Shaded indicates concentrations exceeding GWQS TABLE 1 (17 of 27) Historic Summary Of Monitoring Parameters Up To The 4th Quarter 2013 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Parameter GWQS Carbon Tetrachloride (5 M9'L) Chloride No GWQS (mg/L) Chloroform (™H9"-) Chloromethane (30 ug/L) Methylene Chloride (5 pg/L) Nitrate, Nitrate + Nitrite (10 mg/L) TW4-14 1st Qtr 3/16/05 2nd Qtr 5/25/05 3rd Qtr 8/31/05 4th Qtr 12/7/05 1st Qtr 3/9/06 2nd Qtr 6/14/06 3rd Qtr 7/20/06 4th Qtr 11/8/06 1st Qtr 2/28/07 2nd Qtr 6/27/07 3rd Qtr 8/15/07 4th Qtr 10/10/07 1st Qtr 3/28/08 2nd Qtr 6/25/08 3rd Qtr 9/10/08 4th Qtr 10/15/08 1st Qtr 3/4/09 2nd Qtr 6/23/09 3rd Qtr 9/14/09 4th Qtr 12/16/09 1st Qtr 3/3/10 2nd Qtr 6/14/10 3rd Qtr 8/10/10 4th Qtr 10/15/10 1st Qtr 2/15/11 2nd Qtr 6/14/11 3rd Qtr 8/16/11 4th Qtr 11/15/11 1st Qtr 1/17/12 2nd Qtr 6/14/11 3rd Qtr 8/29/12 4th Qtr 10/3/12 1st Qtr 2/7/13 2nd Qtr 5/29/13 3rd Qtr 8/29/13 4th Qtr 11/6/13 NS NS NS NS NS NS NS <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NS NS NS NS NS NS NS 37 38 38 36 38 57 35 34 40 35 36 38 34 33 49 35 29 25 24 33 15 20 35 37 37 35 2 38 6 37 6 36 5 NS NS NS NS NS NS NS NS <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NS NS NS NS NS NS NS <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NS NS NS NS NS NS NS <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NS NS NS NS NS NS NS 24 23 1 4 1 1 0 8 04 1 6 1 38 0 76 1 6 1 4 1 5 1 4 2 5 29 2 8 2 9 1 8 1 4 26 1 7 1 9 3 3 3 9 39 46 4 4 4 5 4 8 NS = not sampled Shaded indicates concentrations exceeding GWQS TABLE 1 (18 of 27) Historic Summary Of Monitoring Parameters Up To The 4th Quarter 2013 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Parameter GWQS Carbon Tetrachloride (5 MQ/L) Chloride No GWQS (mg/L) Chloroform (70 pg/L) Chloromethane (30 pg/n Methylene Chionde (5 pg/L) Nitrate, Nitrate + (10 mg/L) Nitrite TW4-16 1st Qtr 3/16/05 2nd Qtr 5/25/05 3rd Qtr 8/31/05 4th Qtr 12/7/05 1st Qtr 3/9/06 2nd Qtr 6/14/06 3rd Qtr 7/20/06 4th Qtr 11/8/06 1st Qtr 2/28/07 2nd Qtr 6/27/07 3rd Qtr 8/15/07 4th Qtr 10/10/07 1st Qtr 3/28/08 2nd Qtr 6/25/08 3rd Qtr 9/10/08 4th Qtr 10/15/08 1st Qtr 3/4/09 2nd Qtr 6/23/09 3rd Qtr 9/14/09 4th Qtr 12/17/09 1st Qtr 2/24/10 2nd Qtr 6/14/10 3rd Qtr 8/24/10 4th Qtr 10/15/10 1st Qtr 2/22/11 2nd Qtr 5/26/11 3rd Qtr 8/17/11 4th Qtr 11/16/11 11112/7/11 1st Qtr 1/18/12 2nd Qtr 5/26/11 3rd Qtr 8/30/12 4th Qtr 10/3/12 1st Qtr 2/7/13 2nd Qtr 5/30/13 3rd Qtr 9/5/13 4th Qtr 11/7/13 NA NA <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA NA NA 64 60 55 60 62 79 75 65 69 52 58 71 89 73 76 79 76 77 64 72 71 86 81 63 38 48 53 59 59 58 1 49 8 54 4 56 6 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 240 212 85 14 39 13 52 136 87 26 7 1 1 4 11 10 39 2 1 4 3 3 15 16 92 134 NA NA <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 32 26 1 1 24 NA NA <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 43 5.9 21 8.9 2 7 6.6 1 8 5.1 1 26 14 6.6 1 4 1 7 4 21 <0 1 <0 1 <0 1 <0 1 <0 1 <0 1 <0 1 <0 1 <0 1 1 4 3 1 9 27 56 123 99 54 44 <0 1 1 5 10.5 9 8 96 89 8 8 52 42 47 46 3 3 7 5 1 7 04 0 1 1 4 (1) VOCs were resampled because laboratory missed holding time NA = not analyzed Shaded indicates concentrations exceeding GWQS TABLE 1 (19 of 27) Historic Summary Of Monitoring Parameters Up To The 4th Quarter 2013 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Parameter GWQS Carbon Tetrachloride (5 pg/L) Chloride No GWQS (mg/L) Chloroform (7Q pg/u Chloromethane oo pg/u Methylene Chloride (5 pg/L) Nitrate, Nitrate + Nitnte (10 mg/L) TW4-18 1st Qtr 3/16/05 2nd Qtr 5/25/05 3rd Qtr 8/31/05 4th Qtr 12/7/05 1st Qtr 3/9/06 2nd Qtr 6/14/06 3rd Qtr 7/20/06 4th Qtr 11/8/06 1st Qtr 2/28/07 2nd Qtr 6/27/07 3rd Qtr 8/15/07 4th Qtr 10/10/07 1st Qtr 3/28/08 2nd Qtr 6/25/08 3rd Qtr 9/10/08 4th Qtr 10/15/08 1st Qtr 3/4/09 2nd Qtr 6/23/09 3rd Qtr 9/14/09 4th Qtr 12/22/09 1st Qtr 2/24/10 2nd Qtr 6/14/10 3rd Qtr 8/12/10 4th Qtr 10/15/10 1st Qtr 2/22/11 2nd Qtr 5/26/11 3rd Qtr 8/17/11 4th Qtr 11/16/11 12/7/11 1st Qtr 1/18/12 2nd Qtr 6/13/12 3rd Qtr 9/11/12 4th Qtr 10/3/12 1st Qtr 2/13/13 2nd Qtr 6/13/13 3rd Qtr 9/5/13 4th Qtr 11/13/13 NA NA <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA NA NA 41 36 35 35 34 30 28 32 27 23 23 26 30 29 30 26 30 41 35 37 50 52 36 23 23 18 30 26 27 23 1 22 9 36 2 37 1 38 29 8 39 14 12 12 10 8 12 5 9 2 8 89 74 64 57 8 9 4 11 16 13 82 69 29 29 30 39 26 29 28 25 24 38 30 34 9 37 9 41 44 3 NA NA <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 28 1 1 1 6 27 NA NA <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 14 1 12.9 13.3 73 5 9 47 6 1 57 5 1 49 50 44 07 46 4 9 52 52 62 59 54 5 1 90 90 10.0 10.0 90 46 6 3 4 4 66 66 60 56 89 12.1 14.2 (1) VOCs were resampled because laboratory missed holding time NA = not analyzed Shaded indicates concentrations exceeding GWQS TABLE 1 (20 of 27) Historic Summary Of Monitonng Parameters Up To The 4th Quarter 2013 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Parameter GWQS Carbon Tetrachloride (5H9"-) Chloride No GWQS (mg/L) Chloroform (70 M9/L) Chloromethane (30 ug/L) Methylene Chloride (5 pg/L) Nitrate, Nitrate + Nitrite (10 mg/L) TW4-19 cHlorofrom pumpxng well 1st Qtr 3/16/05 2nd Qtr 5/25/05 3rd Qtr 8/31/05 4th Qtr 12/7/05 1st Qtr 3/9/06 2nd Qtr 6/14/06 3rd Qtr 7/20/06 4th Qtr 11/8/06 1st Qtr 2/28/07 2nd Qtr 6/27/07 3rd Qtr 8/15/07 4th Qtr 10/10/07 1st Qtr 3/28/08 2nd Qtr 6/25/08 3rd Qtr 9/10/08 4th Qtr 10/15/08 1st Qtr 3/4/09 2nd Qtr 6/23/09 3rd Qtr 9/14/09 4th Qtr 12/22/09 1st Qtr 2/17/10 2nd Qtr 6/14/10 3rd Qtr 8/16/10 4th Qtr 10/15/10 1st Qtr 2/17/11 2nd Qtr 6/7/11 3rd Qtr 8/17/11 4th Qtr 11/17/11 1,112/5/11 1st Qtr 1/23/12 2nd Qtr 6/6/12 3rd Qtr 9/4/12 4th Qtr 10/3/12 1st Qtr 2/13/13 2nd Qtr 6/5/13 3rd Qtr 9/3/13 4th Qtr 10/29/13 NA NA <5 0 <50 <50 <50 <50 NA NA NA 81 86 116 Did not sample 1 6 1 3 1 9 1 9 29 <1 0 86 12 1 2 1 2 15 16 1 3 42 49 1 3 17 8.3 2 1 5.4 1 5 1 1 35 4 5.15 " 5.15 20.7 6 42 123 134 133 129 132 131 128 113 124 127 132 43 124 144 132 142 146 135 148 148 148 138 149 149 150 164 148 179 134 2,200 1,200 1,400 2,800 1,200 1,100 1,120 1,050 1,200 1,100 1,100 1,800 1,000 3,600 _4,200 1,100 990 6,600 4,700 940 1,800 2,000 JL200 3.400 4,000 970 2,200 650 460 950 _1500 4,210 2,070 8,100 942 NA NA <5 0 <50 <50 <50 <50 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 26 NA NA <5 0 <50 <50 <50 <50 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <0 1 53 57 4 6 4. 52 43 46 4 4 1 4 22 28 35.2 47.8 3 2 24 <0 1 26 7 2 44 5 9 _27 17^0 12 0 30 5 0 0 6 2 4 2 5 4 1 80 30 17.6 47 (1) VOCs were resampled because laboratory missed holding time NA = not analyzed Bold and italics indicates the MDL exceeded the GWQS Shaded indicates concentrations exceeding GWQS TABLE 1 (21 of 27) Historic Summary Of Monitoring Parameters Up To The 4th Quarter 2013 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Parameter GWQS Carbon Tetrachloride is ug/L) Chloride No GWQS (mg/L) Chloroform (70 ug/L) Chloromethane (30 ng/L) Methylene Chloride (5 Mg/L) Nitrate, Nitrate + Nitrite (10 mg/L) TW4-20 chioto pumping weN 1st Qtr 3/16/05 2nd Qtr 5/25/05 3rd Qtr 8/31/05 4th Qtr 12/7/05 1st Qtr 3/9/06 2nd Qtr 6/14/06 3rd Qtr 7/20/06 4th Qtr 11/8/06 1st Qtr 2/28/07 2nd Qtr 6/27/07 3rd Qtr 8/15/07 4th Qtr 10/10/07 1st Qtr 3/28/08 2nd Qtr 6/25/08 3rd Qtr 9/10/08 4th Qtr 10/15/08 1st Qtr 3/4/09 2nd Qtr 6/23/09 3rd Qtr 9/14/09 4th Qtr 12/14/09 1st Qtr 2/17/10 2nd Qtr 6/14/10 3rd Qtr 8/16/10 4th Qtr 10/15/10 1st Qtr 2/23/11 2nd Qtr 6/1/10 3rd Qtr 8/17/11 4th Qtr 11/16/11 1st Qtr 1/23/12 2nd Qtr 6/6/12 3rd Qtr 9/4/12 4th Qtr 10/3/12 1st Qtr 2/11/13 2nd Qtr 6/5/13 3rd Qtr 9/3/13 4th Qtr 10/29/13 NA <10 <250 <500 <500 <1000 NA 7 1 3 1 22 3 5 68 9 13 15 ~5.7 4 9 8.4 14 27 11 12 20 27 10 7.3 7.2 10 33 26 22 " 19.6 32.5 25.7 17.3 NA NA 131 120 235 134 124 124 112 117 170 132 191 156 168 164 164 153 187 179 200 196 203 220 177 207 186 207 262 289 302 252 250 260 272 NA Monitor well was not installed 39,000 3,800 19,000 9,200 61,000 5,300 11,000 4,400 1,800 5,200 9,000 13,000 30.000 21,000 8,200 6,800 13,000 15,000 3,500 18,000 15,000 24,000 31,000 8,100 3,800 7,900 11,000 36,000 13,000 _.9,000 18,500 26,300 26,800 15,700 NA <10 <250 <500 <500 <10OO <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 1 9 NA <10 <250 <500 <500 <1000 <1 0 NA <1 0 <1 0 <1 0 22 1 1 1 8 1 9 1 5 1 2 37 5.2 42 44 30 32 37 22 5.5 19.0 2 1 3 1 25 1 3 1 21 1 3 2 14 1 37 10.1 29 1 3 8 94 29 3 5 4 2! 23 2 1 56 0 9 80 44 5 5 5 1 2 9 3 3 5 3 2 0' 56 53 46 4 4 48 65 42 7 9 11.0 10.8 110 9 1 98 87 96 (1) VOCs were resampled because laboratory missed holding time NA = not analyzed Bold and italics indicates the MDL exceeded the GWQS Shaded indicates concentrations exceeding GWQS TABLE 1 (22 of 27) Historic Summary Of Monitoring Parameters Up To The 4th Quarter 2013 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Parameter GWQS Carbon Tetrachloride (5 MH/L) Chloride No GWQS (mg/L) Chloroform (70 ug/L) Chloromethane (30 P9/L) Methylene Chloride (5 ug/L) Nitrate, Nitrate + Nitrite (10 mg/L) TW4-21 1st Qtr 3/16/05 2nd Qtr 5/25/05 3rd Qtr 8/31/05 4th Qtr 12/7/05 1st Qtr 3/9/06 2nd Qtr 6/14/06 3rd Qtr 7/20/06 4th Qtr 11/8/06 1st Qtr 2/28/07 2nd Qtr 6/27/07 3rd Qtr 8/15/07 4th Qtr 10/10/07 1st Qtr 3/28/08 2nd Qtr 6/25/08 3rd Qtr 9/10/08 4th Qtr 10/15/08 4th Qtr 11/18/09 1st Qtr 3/11/09 2nd Qtr 6/23/09 3rd Qtr 9/14/09 4th Qtr 12/22/09 1st Qtr 2/25/10 2nd Qtr 614/10 3rd Qtr 8/13/10 4th Qtr 10/15/10 NA <5 0 <1 0 <2 5 <2 5 <2 5 <1 0 <1 0 NA <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 Monitor well was not installed 2 1 5.8 7 1 7 1 6 9.2 1 2 NA NA NA 353 " 347 318 357 296 306 327 300 288 331 271 244 284 279 291 281 256 " 228 266 278 210 192 78 86 120 120 108 139 160 300 140 120 NA 390 180 120 170 180 200 200 160 ~17u" 210 390 200 NA <5 0 <1 0 <2 5 <2 5 <2 5 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA <2 0 <1 0 <1 0 <1 0 <1 0 <To" <1 0 <1 0 <1 0 NA <5 0 <1 0 <2 5 <2 5 <2 5 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA <2 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA 14 6 10.1 96 8 5 10.2 8 9 87 87 86 86 8 3 14 3 88 7 57 8 0 8 3 8 1 92 84 8 4 12.0 14.0 70 9 0 12.0 14.0 13.0 15.0 11.0 13.0 14 0 1st Qtr 2/22/11 2nd Qtr 6/28/11 3rd Qtr 8/17/11 4th Qtr 11/16/11 11112/7/11 1st Qtr 1/19/12 2nd Qtr 6/13/12 3rd Qtr 9/13/12 4th Qtr 10/4/12 1st Qtr 2/13/13 " 2nd Qtr 6/18/13 3rd Qtr 9/13/13 4th Qtr 11/13/13 <1 0 1 2 48 63 67 6.4 5.4 6 7 5.25 3 49 2 13 303 290 287 287 228 285 142 270 221 243 207 206 230 290 460 390 420 400 410 _J90 282 328 244 204 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 11.8 13.8 10.3 9 0, (1) VOCs were resampled because laboratory missed holding time NA = not analyzed Shaded indicates concentrations exceeding GWQS TABLE 1 (23 of 27) Historic Summary Of Monitoring Parameters Up To The 4th Quarter 2013 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Parameter GWQS Carbon Tetrachloride (5 pg/L) Chloride No GWQS (mg/L) Chloroform (7Q pg/u Chloromethane (30 pg/L) Methylene Chloride (5 pg/L) Nitrate, Nitrate + Nitrite (10 mg/L) TW4-22 nitrate pumping well 1st Qtr 3/16/05 2nd Qtr 5/25/05 3rd Qtr 8/31/05 4th Qtr 12/7/05 1st Qtr 3/9/06 2nd Qtr 6/14/06 3rd Qtr 7/20/06 4th Qtr 11/8/06 1st Qtr 2/28/07 2nd Qtr 6/27/07 3rd Qtr 8/15/07 4th Qtr 10/10/07 1st Qtr 3/28/08 2nd Qtr 6/25/08 3rd Qtr 9/10/08 4th Qtr 10/15/08 4th Qtr 11/18/09 1st Qtr 3/11/09 2nd Qtr 6/23/09 3rd Qtr 9/14/09 4th Qtr 12/29/09 1st Qtr 3/3/10 2nd Qtr 6/14/10 3rd Qtr 8/24/10 4th Qtr 10/15/10 1st Qtr 2/22/11 2nd Qtr 6/1/11 3rd Qtr 8/17/11 4th Qtr 11/16/11 (1) 12/7/11 1st Qtr 1/19/12 2nd Qtr 6/13/12 3rd Qtr 9/12/12 4th Qtr 10/4/12 1st Qtr 2/11/13 2nd Qtr 6/5/13 3rd Qtr 9/3/13 4th Qtr 10/29/13 NA <5 0 <5 0 <10 <10 <10 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA <2 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 1 3 1 2 3 24 3 35 3 25 8 09 NA NA NA Monitor well was not installed 253 236 221 221 236 347 273 259 238 519 271 524 539 177 177 391 175 427 134 130 134 114 138 120 174 36 35 130 130 586 487 501 NA 340 290 320 390 280 864 350 440 740 530 440 1,400 1,200 6,300 630 390 730 2,300 _ 380 2.200 540 340 340 1,300 210 450 _400 200 120 121 330 10,600 12,500 9,640 13,300 NA <5 0 <5 0 <10 <10 <10 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA <2 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA <5 0 <5 0 <10 <10 <10 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <2 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA NA 18.2 15.7 15.1 15.3 14.3 14.5 20.9 19.3 193 18.8 39.1 41.9 38.7 36.3 20.7 20 6 40.3 17.8 36 8 19.0 15 0 16.0 18.0 170 15.0 190 14.0 12.8 70 14.0 58.0 50.2 29.7 45.2 (1) VOCs were resampled because laboratory missed holding time NA = not analyzed Shaded indicates concentrations exceeding GWQS Bold and italics indicates the MDL exceeded the GWQS TABLE 1 (24 of 27) Historic Summary Of Monitoring Parameters Up To The 4th Quarter 2013 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Parameter GWQS Carbon Tetrachloride (5 pg'L) No Chloride GWQS (mg/L) Chloroform (70 pg/L) Chloromethane (30 pg/L) Methylene Chloride (5 pg/L) Nitrate, Nitrate + Nitrite (10 mg/L) TW4-23 2nd Qtr 6/27/07 3rd Qtr 8/15/07 4th Qtr 10/10/07 1st Qtr 3/28/08 2nd Qtr 6/25/08 3rd Qtr 9/10/08 4th Qtr 10/15/08 4th Qtr 11/18/09 1st Qtr 3/4/09 2nd Qtr 6/23/09 3rd Qtr 9/14/09 4th Qtr 12/16/09 1st Qtr 2/24/10 2nd Qtr 6/14/10 3rd Qtr 8/24/10 4th Qtr 10/15/10 1st Qtr 2/16/11 2nd Qtr 6/14/11 3rd Qtr 8/16/11 4th Qtr 11/15/11 1st Qtr 1/17/12 2nd Qtr 5/31/12 3rd Qtr 8/29/12 4th Qtr 10/3/12 1st Qtr 2/7/13 2nd Qtr 5/30/13 3rd Qtr 9/5/13 4th Qtr 11/7/13 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA <2 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA 47 46 43 41 41 35 51 41 43 43 37 45 40 40 34 44 44 41 43 40 44 46 45 43 6 44 7 48 43 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA <2 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA <2 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA <2 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <0 1 <0 1 <0 1 <0 1 <0 1 <0 05 <0 05 NA <0 1 <0 1 <0 1 <0 1 <0 1 <0 1 <0 1 <0 1 <0 1 <0 1 <0 1 <0 1 <0 1 <0 1 <0 1 <0 1 <0 1 0 1 <0 1 <0 1 NA = not analyzed Shaded indicates concentrations exceeding GWQS TABLE 1 (25 of 27) Historic Summary Of Monitoring Parameters Up To The 4th Quarter 2013 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Parameter GWQS Carbon Tetrachloride (5 ug/L) Chloride No GWQS (mg/L) Chloroform <70Mfl/L) Chloromethane (30 M9/L) Methylene Chloride (5 Mg/L) Nitrate, Nitrate + Nitrite (10 mg/L) TW4-24 nitrate pumping wdl 2nd Qtr 6/27/07 3rd Qtr 8/15/07 4th Qtr 10/10/07 1st Qtr 3/28/08 2nd Qtr 6/25/08 3rd Qtr 9/10/08 4th Qtr 10/15/08 4th Qtr 11/18/09 1st Qtr 3/4/09 2nd Qtr 6/23/09 3rd Qtr 9/14/09 4th Qtr 12/16/09 1st Qtr 2/25/10 2nd Qtr 6/14/10 3rd Qtr 8/24/10 4th Qtr 10/15/10 1st Qtr 2/17/11 2nd Qtr 5/26/11 3rd Qtr 8/17/11 4th Qtr 11/16/11 11112/7/11 1st Qtr 1/16/12 2nd Qtr 6/6/12 3rd Qtr 8/30/12 4th Qtr 10/3/12 1st Qtr 2/11/13 2nd Qtr 6/5/13 3rd Qtr 8/30/13 4th Qtr 10/29/13 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA <2 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA 770 791 692 740 834 1180 1130 1010 759 618 1080 896 639 587 522 1100 1110 967 608 373 355 489 405 1260 916 998 1030 NA <2 0 <1 0 <1 0 <1 0 26 22 1 5 1 5 1 4 29 1 4 1 5 1 4 1 2 1 3 1 7 1 8 1 4 1 8 1 1 1 7 1 2 1 1 174 21 8 32 5 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA <2 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA <2 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA 261 29 24.7 24 4 45 3 38 4 44.8 30.5 30.4 30.7 28.3 33.1 30 31 31 35 34 35 37 37 37 38 35.9 23.7 33 35 (1) VOCs were resampled because laboratory missed holding time NA = not analyzed Shaded indicates concentrations exceeding GWQS TABLE 1 (26 of 27) Historic Summary Of Monitoring Parameters Up To The 4th Quarter 2013 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Parameter GWQS Carbon Tetrachloride (5M3/L) Chloride No GWQS (mg/L) Chloroform (70 ug/L) Chloromethane (30 Mg/L) Methylene Chloride (5 Mg/L) Nitrate, Nitrate + Nitrite (10 mg/L) TW4-25 2nd Qtr 6/27/07 3rd Qtr 8/15/07 4th Qtr 10/10/07 1st Qtr 3/28/08 2nd Qtr 6/25/08 3rd Qtr 9/10/08 4th Qtr 10/15/08 4th Qtr 11/18/09 1st Qtr 3/4/09 2nd Qtr 6/23/09 3rd Qtr 9/14/09 4th Qtr 12/14/09 1st Qtr 2/23/10 2nd Qtr 6/14/10 3rd Qtr 8/10/10 4th Qtr 10/15/10 1st Qtr 2/16/11 2nd Qtr 5/25/11 3rd Qtr 8/16/11 4th Qtr 11/15/11 1st Qtr 1/16/12 2nd Qtr 5/31/12 3rd Qtr 9/4/12 4th Qtr 10/3/12 1st Qtr 2/11/13 2nd Qtr 6/5/13 3rd Qtr 9/4/13 4th Qtr 10/31/13 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA <2 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA 395 382 358 374 344 333 366 332 328 328 371 296 306 250 312 315 321 276 294 304 287 334 338 190 136 119 88 6 <1 0 <1 0 <1 0 <1 0 <1 0 NA <2 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 22 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA <2 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA <2 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA 17.1 29 17 18 7 22.1 188 21 3 15.3 15.3 3 3 14 2 14.4 16 14 15 15 16 16 16 16 16 17 _1Z 9 04 5 24 6 6 (1) VOCs were resampled because laboratory missed holding time NA = not analyzed Shaded indicates concentrations exceeding GWQS TABLE 1 (27 of 27) Historic Summary Of Monitoring Parameters Up To The 4th Quarter 2013 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Parameter GWQS Carbon Tetrachloride (5 M9'L) Chloride No GWQS (mg/L) Chloroform (70 U9'L) Chloromethane (30 ug/L) Methylene Chloride (5 P^L) Nitrate, Nitrate + Nitrite (10 mg/L) TW4-26 2nd Qtr 6/14/10 3rd Qtr 8/24/10 4th Qtr 10/15/10 <1.0 <1.0 <1.0 1st Qtr 2/16/11 2nd Qtr 5/26/11 3rd Qtr 8/17/11 4th Qtr 11/16/11 11112/7/11 <1.0 <1.0 <1.0 <1.0 1st Qtr 1/18/12 2nd Qtr 6/6/12 3rd Qtr 9/11/12 4th Qtr 10/3/12 1st Qtr 2/7/13 2nd Qtr 6/13/13 3rd Qtr 9/5/13 4th Qtr 11/7/13 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 22 13 5.2 5.4 2 2.9 2.8 5.2 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 19 7 4.1 4.9 4.9 <1.0 <1.0 <1.0 <1.0 16.6 14.5 17.6 15.9 4.9 2.12 2.81 3.37 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.6 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.6 <1.0 7.9 9.0 9.6 10.0 10.0 11.0 10.0 11.0 12.0 9.0 12.0 12.5 13.6 11.7 15.9 TW4-27 1st Qtr 1/18/12 2nd Qtr 6/13/12 3rd Qtr 9/4/12 4th Qtr 10/3/12 1 st Qtr 2/7/13 2nd Qtr 6/13/13 3rd Qtr 8/30/13 4th Qtr 11/6/13 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 18.8 20.3 19 21.8 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1 0 <1.0 <1.0 <1.0 <1.0 <1.C <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 24.0 41.0 37.0 36.0 312 29.4 27.2 29.8 TW4-28 2nd Qtr 6/19/13 3rd Qtr 8/29/13 4th Qtr 11/6/13 <1.0 <1.0 <1.0 44.6 45.3 45.3 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 14.9 17.3 16.2 TW4-29 2nd Qtr 6/19/13 2nd Qtr 7/11/13 3rd Qtr 9/26/13 4th Qtr 11/13/13 <1.0 <1.0 <1.0 <1.0 44.8 37.7 41.4 42.5 242 262 246 260 <1.0 <1 0 <1 0 <1.0 <1.0 <1.0 <1.0 <1.0 4 6 3.5 4.2 4.1 TW4-30 2nd Qtr 6/19/13 3rd Qtr 9/26/13 4th Qtr 11/13/13 <1.0 <1.0 <1.0 36 36.3 35.9 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 1.0 1 1 2 TW4-31 2nd Qtr 6/19/13 3rd Qtr 9/5/13 4th Qtr 11/7/13 <1.0 <1.0 <1.0 28.4 29.4 <1.0 <1.0 28 <1.0 <1.0 <1.0 <• 0 <1.0 <1.0 <1.0 1.3 1.1 1.3 TW4-32 4th Qtr 11/14/13 <1.0 52.1 <1.0 <1.0 |<1.0 4^3 1.8 1.6 TW4-33 4th Qtr 11/14/13 <1.0 '.2fj^26^^ l < 1.0 TW4-34 4th Qtr 11/14/13 <1.0 19.2 <1.0 |<1.0 <1.0 Shaded indicates concentrations exceeding GWQS. (1) VOCs were resampled because laboratory missed holding time. Table 2 Summary of QA/QC Samples 4th Quarter 2013 Parameter GWQS Dup MW-32 icate of MW-32 TW4-65 RPD Dup TW4-16 icate of TW4-16 TW4-70 RPD Nitrate + Nitrite (as N) Chloride Chloroform Carbon tetrachloride Chloromethane Methylene Chloride 10 mg/L none 70pgVLj 5 pg/L 30 pg/L 5 pg/L" <0. <1.0 <[.0 <1.0 <1.0 <0.l 35.7 <1.0 <1.0 <i.o <i.o nc 33.3 nc nc nc nc 7.0 <1.0 <K0_ <1.0 J.37 56.6 13.4 \35 56_5 13.1 <1.0 <1.0 <1.0 1.5 0.2 2.3 nc nc nc nc = not calculated Tabel 3 Chloroform Mass Removal Calculations DUSA White Mesa Mill, Bland, Utah 4th Quarter 2013 Well ID MW4 MW-26 TW4-4 TW4-19 TW4-20 TW4-22 TW4-24 TW4-25 Ave. Chloroform (ug/L) Chloroform (g/L) Chloroform (Ibs/L) Chloroform (lbs/gal) Total gallons pumped 3rd qtr 2013 lbs of chloroform removed Gallons of chloroform removed 1,410 1 41E-03 3 12E-06 1 18E-05 70,340 0.83 0 07 1,410 1.41E-03 3 12E-06 1 18E-05 24,208 0.29 0 02 1,360 1 36E-03 3 00E-06 1 14E-05 60,234 0.69 0 06 942 9 42E-04 2 08E-06 7.88E-06 403,974 3.18 0.26 15,700 1 57E-02 3 47E-05 1 31E-04 19,280 2.53 0 21 13,300 1 33E-02 2.94E-05 1 11E-04 24,952 2.78 0.23 32 5 3 25E-05 7 18E-08 2.72E-07 260,555 0.07 0 006 0 0 00E+00 0 00E+00 0 00E+00 126,577 0.00 0 00 total lbs of chloroform removed 10.36 total gallons of chloroform removed 0 84