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HomeMy WebLinkAboutDRC-2014-001621 - 0901a06880403c7dDepartment of Environmental Quality Amanda Smith Executive Director GARY R HERBERT Governor DIVISION OF RADIATION CONTROL Rusty Lundberg Director SPENCER J COX Lieutenant Governor MEMORANDUM DRC-2014-001621 DATE: TO: FROM: SUBJECT: Review of the 3rd 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 November 19, 2013, 3rd 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, and TW4-31. 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, and TW4-28. 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, and tw4-31. 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 ofthe 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 TW4-3 and its duplicate sample TW4-65, TW4-8 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 ofthe 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-20andMW-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 3rd quarter 2013 is 31.1 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 ug/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 ofthe Chloroform Contaminate Plume and Its Associated Contaminants Bounding Chloroform Plume Groundwater monitoring data for the 3rd 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 ug/L (GWQS = 70 ug/L). However, there is a concern about the chloroform concentrations at TW4-29 that continue to exceed the GWQS at 246 ug/L (see Table 1, 27 of 27 below). Although the groundwater contour lines on the map included in the Report "The Kriged 3rd Quarter, 2013 Water Levels and Estimated Chloroform Capture Zones Chloroform Capture Zones map" ("Map") [EFR 2013] show that there is a down gradient well TW4-30, located approximately 200 feet west of TW4-29 and a cross/down gradient well TW4-27, located approximately 200 feet north of TW4-29 both with chloroform concentrations of < 1.0 ug/L there is still a concern that the chloroform plume may not be adequately bound (see Map in Attachment 1). Therefore, two new wells, TW4-33 and TW4-34, where installed in September of 2013 define chloroform plume in the vicinity of TW4- 29. On November 14,2013 both new wells were sampled but the analytical results were not available at the time of this Report. However, the analytical results for TW4-33 and TW4-34 were reported in the Contamination Investigation Report TW4-12 and TW4-27 Areas White Mesa Uranium Mill Near Blanding, Utah ("CIR") submitted to DRC on January 24, 2014. The CIR reported that TW4-33, located northwest approximately 400 feet cross/up gradient of TW4-29, had a chloroform concentration of 126 ug/L and TW4-34, located south approximately 200 feet cross gradient of TW4-29 had a chloroform concentration of <1.0 ug/L. Based on the chloroform concentrations from TW4-33, TW4-34; and other wells in the vicinity of TW4-29 it appears that the chloroform plume is bound. However, the CIR is currently under review and a more detailed written report evaluation of the chloroform plume in the vicinity of TW4-29 will be completed. Monitor Wells Exceeding Chloroform Concentrations of 70ug/L Seven monitor wells: TW4-1, TW4-2, TW4-7, TW4-10, TW4-11, TW4-21, and TW4-29 exceed chloroform concentrations of 70ug/L and have all increased concentrations since the 2nd quarter 2013. Monitor Wells with Chloroform Concentrations between 1 ug/L and 70ug/L Four monitor wells: TW4-5, TW4-6, TW4-18, and TW4-26 chloroform concentrations of <70ug/L. TW4-18 appears to have a increasing trend. Page 5 Pumping Wells Chloroform Concentrations Pumping wells MW-4, MW-26, TW4-4, TW4-19, TW4-20, and TW4-22 exceed chloroform concentrations of 70ug/L. Pumping well TW4-24 had a historic high chloroform concentration of 21.8 ug/L and TW4-25 have non-detectable chloroform concentrations (<1.0 ug/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 ug/L): MW-32, TW4-3, TW4-8, TW4-9, TW4-12, TW4-13, TW4-14, TW4-16, TW4-23, TW4-27, TW4-28, TW4-30, and TW4-31. 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 and TW4-27 continue to exceed the GWQS (10 mg/L). The CIR addressing these nitrate exceedances is currently under review. Conclusions on Compliance with the Permit and QAP Per the DRC review it appears that the Report complies with Peimit and QAP. Therefore a letter will be drafted for the Director Signature, notifying EFR of the review and closing-out ofthe 3 rd 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. Page 7 Attachment 1 The Kriged 3rd Quarter, 2013 Water Levels and Estimated Chloroform Capture Zones Chloroform Capture Zones map _0 to A; 95 <0 A; <6 N-0 iff CS53 27 CS593 fo 25 <6 N-01 0_ PIEZ 5= 531 4-21 / / / // f if 4-18 19 <0 05 TW4-22 <0 TW4- 4-05 05581 4 Iff 4-12 OSoBJi _ 4- 0 TW4-16 TW 4-13 0556 OE TW4-0 55^ 31 554 065S* 1551 5540 TW 5535 TW 5521 ^3 TW4-23 55 2? 25 538 533 ft 4- 53 69 feet 10 PIEZ-04 EXPLANATION estimated capture zone boundary stream tubes Q t S i resulting from chloroform 0 I 1 I pumping "JJJSM perched monitoring well showing elevation in tect amsl ^^r^Le* temporary perched monttonng well ^J3a*' showing elevation in feet amsl perched piezometer showing "33E6 ekwationinleetamsi TWM2 temporary perched monitoring well #3534 installed September. 2013 showing etevalion in feet anrsl NOTE. MW-4. MW-26. TW4-4. TW4-19 and TW4-20 are cHorofomi pumping wells TW4-22. TW4-24. TW4-25, and TWN-2 are nitrate pumping wells HYDRO GEO CHEM, ENC. KRIGED 3rd QUARTER, 2013 WATER LEVELS AND ESTIMATED CHLOROFORM CAPTURE ZONES WHITE MESA SITE (detail map) f_F£RfcKCfc FiGURE Hy718000/nov13/Uwl0913cz srf D-3 TABLE 1 (1 of 27) Historic Summary Of Monitoring Parameters Up To The 3rd Quarter 2013 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Parameter GWQS Carbon Tetrachloride <5ug/L) Chloride No GWQS (mg/L) Chloroform (70 Hg/L) Chloromethane (30 ug/L) Methylene Chloride (5 ug/L) Nitrate, Nitrate + Nitrite (10 mg/L) MW-4 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 8/6/10 4th Qtr 10/15/10 1st Qt~r"2/23/1l" 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 NA NA <10 <50 <50 <50 <50 NA NA NA 21 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 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 2,30(3 2,600 |§ |y 12,300 JM - 0 2*200 ,800 \t."^ 2,000 £ .^.....MitPW ^ s 1600 K A-*. 2100' ""> 1.500 v** 1,700 1,700 1*600 / 1,500 J3^^130d 670 1 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 <i o" <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 1.4 NA NA <10 <50 <50 <50 <50 <1 0 <1.6 <1 o <1 <1 <1. <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 o <1 o <1 o <1 o <1 0 <1 o" <1 <1 <1 <1 <1 <1 63 71 70 70 60 60 1 2 64 63 70 62 62 58 6 1 64 59 57 52 53 58 40 5 1 48 49 46 49 49 51 48 49 50 48 48 42 49 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 1stQtr2/28/07 NA NA <10 <50 <50 <50 <50 NA NA NA 24 1 9 3^700 55 53 3,300 3,190 54 54^ 3.370 54 12,500 60 NA NA <10 <50 <50 <50 <50 <1 0 <1 0 Well abandonded NA NA <10 <50 <50 <50 <50 <1 0 <1 0 7 1 7 8 69 67 58 73 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 3rd Quarter 2013 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Parameter GWQS Carbon Tetrachloride (5 ug/L) No Chloride 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) 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 3/4/09 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 (1)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 NA NA <5 0 <50 <50 <50 <50 <1 0 "<1. <1 <1 <1 <1 <1. <1 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 NA NA NA NA 1 2 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 3nS 442 1.000 f.iol 2,18$ '. 2 8 2 ~""5|1 300 1.4.00 2,000 "'"'18 1,300 ..630 NA ~M 430 85| 1,101 "~fm 1'6P 2,200 970 ri i,88L 3. 3.1H. NA NA 54 <50 <50 <50 <50 <1 0 <1 <1 <1 <1 <1 <1 <1 NA <2 0 <1 0 <1 <1 <1 <1. <1 <1 <1 <1 <1 <1. 2,120 2,940 <1 0 "<1 0 <1.0 <1 <1 <1" <1 0 <1 0 NA NA <5.0 <50 <50 <50 <50 26 "5~| .1| 14s NA 100; NA <1.0 51 12 30 40 11 b.o 36 1.3 Xl| 29 16 9.34 52.4 33.8 03 02 02 03 02 02 1 4 03 06 04 1 06 01 06 02 01 04 02 0.1 23 02 68 06 07 05 04 09 20 1 7 25 26 1 8 23 2 1 1 2 (1) VOCs were resampled because laboratory missed holding NA = not analyzed Shaded indicates concentrations exceeding GWQS Bold and italics indicates the MDL exceeded the GWQS time TABLE 1 (3 of 27) Historic Summary Of Monitoring Parameters Up To The 3rd Quarter 2013 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Parameter GWQS Carbon Tetrachloride (5 ug/L) No Chloride GWQS (mg/L) Chloroform (70 ug/L) Chloromethane (30 ug/L) Methylene Chloride (5 M9/D 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 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 2/17/10 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 (1> 12/7/1 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 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 o" <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 <1 0 <1 0 <1 0 <1 0 <Vo <1.0 <1.0 <1.0 <1 0 <1 0 <1.0 <1 0 <1 0 <1 0 <1.0 <1 0 <1 0 <1 0 <1 0 <1.0 <ib <1 0 <1.0 <1 0 <1 o" <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 o" <1 0 <1.0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1.0 <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 35 1.8 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 <0.1 <0 1 <01 <0.1 <01 <01 <1 0 < 1 <1.0 <1 0 <1 0 <1 0 < 1 <1 0 <1 0 <0 05 < 1 <0 1 <01 <0 1 <0 1 <0 1 <0 1 <0 1 <0 1 <0 1 <0 1 <0 1 <0 1" <0 1 <0 1 <01 <01 <0 1 <0 1 (1) VOCs were resampled because laboratory missed holding NA = not analyzed Shaded indicates concentrations exceeding GWQS time TABLE 1 (4 of 27) Historic Summary Of Monitoring Parameters Up To The 3rd Quarter 2013 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Parameter GWQS Carbon Tetrachloride W-) Chloride No GWQS (mg/L) Chloroform (70 U9/L) Chloromethane (30 ug/L) Methylene Chloride <5ug/D 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 IstQtr 2/13/13 2nd Qtr 6/19/13 3rd Qtr 9/3/13 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 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 4"1 35 36 40 38 42 39 40 37 6 391 37 6 1.500J 1,700 1,466 tr 1.60¥ .. -in 1,50O "T,3r 1.2 1.3Q0 1,56 1,30 ?.PBL 1,000 1,3 1,100 1,150 NA NA <10 <50 <50 <50 <50 <1 0 <1 <1 <1 <1 <1. <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1.0 <1 0 <1 <1 <1 <1 <1 <1 <1 <1".0 <1 0 <1 0 91 10.6 98 97 94 96 92 8.9 9 84 78 76 8 68 8 15 93 "75 69 73 68 71 68 67 66 66 66 68 66 68 7 1 50 65 "70 69 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 3rd 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 ug/L) Chloromethane (30 ug/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 NA NA <10 <50 ~<50 <50 <50 NA 23 1 8 2 5 2 2 2.1 2 3 2.2 24 2 4 2 2 2 2 2 —2 2 6 25 2 1 2 4 22 1.6 28 2 2 1 1 8 2 5.17 2 65 2 41 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 NA '* 3,7 3,750 3,900 3,500 ' 3,800 3,200 4,120 3,420 '"'2'.300 3,000 340 (?) 3.200 3^300 3,100 2.800 3.200 " 3.100 2,800 3,000 "L600 2;§6o 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 NA <10 <50 <50 <50 <50 <1 0 <1 <1 <1 <1 <1 <1 <1 NA <2 0 <1 0 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 NA NA <10 <50 <50 <50 <50 <1 0 <1 <1 <1 <1 <1. <1 0 <1 0 NA <2 0 <1 o" NA 77 86 80 78 7_5 71 74 76 73 78 73 69 69 74 7 1 80 65 64 66 64 68 87 66 65 70 68 60 70 7 1 77 40 76 8 1 75 9.3 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 3rd Quarter 2013 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Parameter GWQS Carbon Tetrachloride (5 Mg/L) No Chloride GWQS (mg/L) Chloroform (70 ug/L) Chloromethane (30 ug/L) Methylene Chloride (5 ug/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 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 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 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 < 1 0 <1 0 <1 0 <1 0 <1 0 <1.0 <1 0 <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 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 <1 <1 <1 <1 0 <1 0 <1 0 <1 0 <1 0 <1.0 <1.0 <1 0 6 4 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 35 37 35 33 33 7 1 29 1 5 31 33 31 28 28 29 27 26 25 29 28 26 28 30 3 1 33 35 37 40 44 7 1 44 49 4.8 5 1 58 49 NA = not analyzed Shaded indicates concentrations exceeding GWQS. TABLE 1 (7 of 27) Historic Summary Of Monitoring Parameters Up To The 3rd 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 (70Mg/L) Chloromethane (30 ug/L) Methylene Chloride (5 ug/L) Nitrate, Nitrate + Nitrite (10 mg/L) TW4-4 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" 3/4/09 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 NA NA <10 <50 <50 <50 <50 NA <2 0 <1 0 <1 0 <1 0 1 2 1 1 <1.0 1 2 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 NA 37 34 39 41 48 35 36 38 ""41 35 40 39| 38 43 39 38 "39 39 6 38 8 3,100 WOO 3-20l 2.800 2.9$ 2,60 2,850 iM 2,2% 2.400 2.7Q3 2,50;0 2.80| 2,50*0* 2,203 2,5(0 ' 2-200 2^°| 95l T7tiS 1,70j 1.7utj[ JM 1,7(8 1,501 1.500 1,20| 1.50I 1,600 i;4d» 1,431 1,33i 1.3 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 <1 <1 <1 <1 0 <1 0 <1 <1 <1 <1 <1 <1 <1 <1 <1 0 0 0 0 0 0 0 0 0 <1 0 NA NA <10 <50 <50 <50 <50 <1 0 <1 <1 <1 <1 "<1 <1 <1 NA <2 0 <1 0 <1 0 <1.0 <1 0 <1 <1 <1 <1 <1 <1 <1 0 <1 0 <1 <1 <1 <1 <1 <1 <1 NA 100 11.3 99 10.2 95 86 9.7 90 94 95 95 92 KsP 88 82 84 76 66 76 7.3 7 1 70 70 66 70 7 1 7 1 7 1 7 0 74 63 72 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 3rd Quarter 2013 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Parameter GWQS Carbon Tetrachloride (5 "9"-) No Chloride GWQS (mg/L) Chloroform (7Q"g/L) Chloromethane (30 H9"-) Methylene Chloride (5 ug/L) Nitrate, Nitrate + Nitrite do "a"-) 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 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 1stQtr2"/25/10~" ~ 2nd Qtr 6/14/10 3rd Qtr 8/11/10 4th Qtr 10/15/10 1st Qtr 2/22/11 2nd Qtr 5/26/11 3rd Qtr 8/7/11 4th Qtr 11/16/11 (1) 12/7/11 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 NA NA <2 5 <2 5 <2.5' <2.5 <1 0 <1 0 <1.0 <1.0 <1 0 <1 <1 <1 <1 <1 <1 <1 <1 <1. <1. <1. <1 <1 <L0 <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 5 391 63 66 51 53 7 47 1 35 26 9.2 9.4 11 93 11 10 12 13 12 85 13 12 12 11 10 9 10 79 76 84 12 8 108 11 2 11 6 NA NA <1 0 <1 0 <1 0 <1 0 <1.0 <1 0 <1 0 <1 0 58 25 3.1 31 NA NA <2.5 <2 5 <2.5 <2 5 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 < 1 o" <1.0 <1 0 <1 0 <1 6" <1 0 <1.6 <1 0 <1 <1 <1 <1. <1. <1.0 <1 0 <1 0 il 0 <1 0 <1.0 <1 0 <1 0 <1 0 <1 0 49 37 60 60 60 59 67 29 78 70 77 82 74 87 79 93 79 75 83 75 68 71 70 72 70 72 75 6 0 58 80 81 77 82 12 78 (1) VOCs were resampled because laboratory missed holding NA = not analyzed Shaded indicates concentrations exceeding GWQS time TABLE 1 (9 of 27) Historic Summary Of Monitoring Parameters Up To The 3rd Quarter 2013 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Parameter GWQS Carbon Tetrachloride (5F9"-) No Chloride GWQS (mg/L) Chloroform (70 M9/L) Chloromethane (30 ug/L) 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 (1) 12/7/11 (2) 11/16/11 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 NA NA <1 0 <1 <1 <1 <1 <1 0 <1 0 <1 <1 <1 <1 <1 <1 <1 0 <1_0 <1 0 <1 0 <1 0 <1 <1 <1 <1 <1 <1 0 <1 0 <1 <1 <1 <1 <1 <1 <io <1 0 <1 0 NA NA NA 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 A 37 9 40 6 <1 0 25 10 17 31 19 11 42 8 46 11 18 18 "52 24 39 37 47 96 16 21 50 38 47 69 9 6 89 4 86 5 93 NA NA <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1.0 <1 0 <1 0 <1. <1 <1 <1 <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 <1 <1 <1 <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 02 04 08 09 1 2 1 0 06 1 4 1 8 06 07 08 1 1 09 1 1 1 0 2 2 27 50 6.1 1 8 25 3 9 43 0 7 03 03 08 08 07 02 01 02 02 02 02 (1) VOCs were resampled because laboratory missed holding (2) Results of the TW4-70 the duplicate sample for TW4-6 NA = not analyzed Shaded indicates concentrations exceeding GWQS time TABLE 1 (10 of 27) Historic Summary Of Monitoring Parameters Up To The 3rd 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 ug/L) Chloromethane (3Q wan.) Methylene Chloride (5 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 NA NA <10 <50 <50 <50 <50 NA <2 0 <1 0 <1 0 <1 0 <1 0 1 <1 0 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 1 5 1 1 1 5 1 4 1 2 1 3 1 3 1 4 1 2 1 NA NA NA NA NA NA <10 <50 <50 <50 <50 <1 0 <1 <1 <1 <1 <1 <1 <1 NA <2.0 "<1"0 <1 <1 <1 <1 <1 <1 <1 <1. <1 <1 <1 <1" <1 <1 <1 <1"0 <1 0 <1 0 NA 52 54 52 53 1 45 47 46 6 51 47 47 42 48 4.16 4 01 37 38 4 1 42 38 39 39 4 36 40 4 1 38 3 9 40 38 38 "3 5 40 42 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 3rd 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 ug/L) Chloromethane (30 ug/L) Methylene Chloride (5 ug/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 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 NA NA NA 41 39 37 39 40 39 42 42 43 46 45 39 44 42 44 44 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 10 1 1 1 3 1 8 25 25 1 5 35 NA NA <1.0 1 7. 2.1 1 0 <1. <1 <1 <1 <1 <1. <f <1.0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 o" <1 0 <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 <To <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 02 03 01 07 02 05 01 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 (1)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 <1.0 <1 0 <1 0 <1.0 <1 0 <1 0 <1 0 <1 0 <1 0 "<1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 51 57 42 45 46 52 45 46 45 45 44 48 47 46 6 45 5 47 5 <1 0 <1 o" <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 <1.0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <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 <01 01 <0.1 0 1 0 1 02 0.3 02 01 <0 1 04 <0 1 01 (1) VOCs were resampled because laboratory missed holding time NA = not analyzed Shaded indicates concentrations exceeding GWQS TABLE 1 (12 of 27) Historic Summary Of Monitoring Parameters Up To The 3rd Quarter 2013 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Parameter GWQS Carbon Tetrachloride (5 "5"-) Chloride No GWQS (mg/L) Chloroform (70 ug/L) Chloromethane (30 ug/U Methylene Chloride (5 ug/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 2728/07 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 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 NA NA NA 42 38 39 41 44 44 42 38 40 35 35 28 58 30 30 30 <1 0 <1.0 <1 0 <1.0 <1 0 <1.0 3.8 1.2 19 21 95 87 1 3 1 <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 <i"o" <1 0 <1 0 <7b" <1 o" <1 0 <1 0 <1 0 <1 o" <1 0 <1 0 2 9 2 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 <To" <1 0 <1 0 <1.0 <1.0 <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 25 23 25 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 <1 0 <1 0 <1 0 <1 0 <1 0 <1"0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 37 47 33 40 34 41 38 21 38 28 23 22 21 20 6 21 4 22.7 <1 0 <1 0 <1.0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 o" <1 0 <1 0 <1 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 1 4 1.5 1 2 1 8 1 3 34 4 23 23 40 3.9 38 4 5 45 40 (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 3rd Quarter 2013 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Parameter GWQS Carbon Tetrachloride (5 ua/L) No Chloride GWQS (mg/L) Chloroform (70 ug/L) Chloromethane (30ug/L) Methylene Chloride (5 ug/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 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 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 NA NA <2 5 <2 5 <5 0 <5 0 <5 0 <1 0 <1 <1 <1 <1 <1 <1 <1. NA <2 0 <1.0 <1 0 <1 0 <1.0 <1.0 <1 0 <1 0 <1 0 <1 <1 <1 <1 <1. <1. <1. <1 <L <1. <1 NA NA NA NA r 1H26 62 1.6 NA NA <25 <2 5 <5 0 <5.0 <5 0 <1.0 <1 <1 <1 <1 <1 <1 <1. NA <2 0 <1 0 <1.0 <1.0 <1 0 <1 0 <1 0 <1 0 <1 0 <10 <1 <1 <1 <1 <1 <1.0 <1 0 <10 <1 0 <1 0 1.6 08 1.1 33 2.4 35 68 57 73 51 73 67 73 99 9 23 NA .6 98 81 3.8 50 1 6 90 33 1 9 1 1 09 08 1 0 1 6 "1 2 56 130 NA = not analyzed Shaded indicates concentrations exceeding GWQS TABLE 1 (14 of 27) Historic Summary Of Monitoring Parameters Up To The 3rd Quarter 2013 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Parameter GWQS Carbon Tetrachloride (5"g"-) Chloride No GWQS (mg/L) Chloroform Chloromethane {3Qug,i.} Methylene Chloride (5 ug/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 1s"tQtr"l/24/12 2nd Qtr 6/13/12 3rd Qtr 9/13/12 4th Qtr 10/3/12 1stQtr2/13~/13 2nd Qtr 6/18/13 3rd Qtr 9/12/13 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 o" <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 OQ ao 860 820 800 28 5820 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 6 <1.0 <1 0 <1 0 <10 <1 0 <1 0 <1 0 <1.0 <1 0 <1 0 1 3 1 6 1 2 NA 87 9 4 94 92 100 100 100 10W m 10^2 9 8 77 73 79 95 "7 3 68 70 66 68 69 67 64 65 73 71 7 1 68 67 30 70 68 74 78 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 3rd 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 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 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 2/13713 " 2nd Qtr 5/29/13 3rd Qtr 8/29/13 NA NA <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <10 <1.0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1.0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <io <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 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 0 <1 0 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1" <1 <1. <1 il <1 <1 NA NA <1 0 <1 0 <1 0 <1 0 <1 0 <1 o" <1 0 <1.0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <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 2.6 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 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 40 8 90 80 65 70 68 80 77 11 t3i0 mo f|2 NA = not analyzed Shaded indicates concentrations exceeding GWQS TABLE 1 (16 of 27) Historic Summary Of Monitoring Parameters Up To The 3rd Quarter 2013 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Parameter GWQS Carbon Tetrachloride Chloride No GWQS (mg/L) Chloroform Chloromethane (30 ug/L) Methylene Chloride (5 ug/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 NA NA <1 0 <1 0 <10 <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 <1 <1. <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 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 <1.0 <1 0 <1 <1 <1. <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1.0 <1 0 <1 0 <1 0 <1.0 <1 0 <1 <1 <1. <1 NA NA <1 0 <1 0 <1 0 <1 o" <1.0 <1.0 <1 0 <1 0 <1 0 <1 0 <1 0 <1.0 <1 0 <1 0 <1 0 <" 1 0 < 1 0 <1 0 <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 o" <1 0 <1.0 <1 0 <1.0 <1 0 <1 0 <1 0 <1 o" <1 0 <1 0 <1 0 <1 0 <1 0 <1.0 <1 0 <1 0 <1.0 <1.0 <1.0 <i o" <1 0 <1 0 <1 0 <i.o <1 0 <1.0 42 43 4.6 43 4 2 4 9 43 08 40 46 44 4 1 38 42 43 4.6 "3 7 1 2 47 4 1 43 52 56 58 55 64 52 5 9 "5 5 6 0 62 59 63 68 72 NA = not analyzed Shaded indicates concentrations exceeding GWQS TABLE 1 (17 of 27) Historic Summary Of Monitoring Parameters Up To The 3rd Quarter 2013 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Parameter GWQS Carbon Tetrachloride Chloride No GWQS (mg/L) Chloroform (70 ug/L) Chloromethane (30 ug/L) Methylene Chloride (5 ug/L) Nitrate, Nitrate + Nitrite (10 mg/L) TW4-14 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 NS NS NS NS NS NS NS <1 0 <1.0 <1.0 <1 0 <1 0 "<1.0 <1 0 <1 <1 <1. <1. <1. <1 <1 <1 <1 <1 <1.0 <1 b <1 <1 <1 <1. <1. <1 <i <1 <1 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 NS NS NS NS NS NS NS NS <1 0 <1 0 <1 0 <1.0 <1.0 <1 0 <1 0 <1 0 <10 <i.o <1 0 <1 <1 <1 <1. <1 <1 <1 <1 <1. <1 NS NS NS NS NS NS NS <1.0 <1 <1 <1 <1. <1~ <1 <1 <1 <1. <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1. <1 <1 <1 <1 <1 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 <i.b <1 0 <1 0 <1 0 <1 0 NS NS NS NS NS NS N.S 24 " 2.3 1 4 1 1 08 "04 1 6 1 38 0.76 1 6 1 4 1 5 1 4 2 5 29 28 29 1.8 1.4 26 1 7 ' 1 9 33 39 39 46 44 45 NS = not sampled Shaded indicates concentrations exceeding GWQS TABLE 1 (18 of 27) Historic Summary Of Monitoring Parameters Up To The 3rd Quarter 2013 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Parameter GWQS Carbon Tetrachloride (5 U9/L) No Chloride GWQS (mg/L) Chloroform (70tig/U Chloromethane »g"-> Methylene Chloride (5 ug/L) Nitrate, Nitrate + Nitrite (10 mg/L) 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 (1) 12/7/1 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 NA NA <1 0 <1 <1 <1 <1 <1. <L <1 <1. <1 <1 <1.0 <1 0 <1 0 <1 0 <1 0 <1 0 <i.b <ib <1 0 <1 <1 <1 <1 <1 <1. <1 <1 <1 <1.0 <ib <1 o <1 o 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 59 581' 49 8 54 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 NA NA 32 26 1.1 24 <1 0 <1 0 <1.0 <1 0 <1 0 <1 0 <1 0 <1 <1 <1" <1 <1 <1 0 <1 0 <1 0 <1 0 <1 0 <01 <01 <01 8.t 2 7 6.6 1 8 5-i _ 1 .26 14 6.6 1 4 1 7 4 21 98 96 89 88 52 42 47 46 33 7 5 1 7 04 01 <0.1 <0 1 <0 1 <0 1 <0 1 <0 1 (1) VOCs were resampled because laboratory missed holding NA = not analyzed Shaded indicates concentrations exceeding GWQS time TABLE 1 (19 of 27) Historic Summary Of Monitoring Parameters Up To The 3rd Quarter 2013 Chloroform Contamination Investigation DUSA White Mesa Mill WeM Sampling Event Parameter GWQS Carbon Tetrachloride Chloride No GWQS (mg/L) Chloroform (70 U9/L) Chloromethane (30 ug/L) Methylene Chloride (5 ug/L) Nitrate, Nitrate + Nitrite do mg/D 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 1stQtr2/28/07 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 (1) 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 NA NA <1.0 <1.0 <1 0 <1 <1 <1 <1 <1. <1. <1 <1. <1 <1 <1 <1 <1. <1 <1 <1. <1 <1 0 <1 0 <1 0 <1 0 <1.0 <1.0 <1 0" <1 <1 <1 <1 <1. NA NA NA <1 0 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 38 29 8 39 14 " 12 12 108 12 5 92 8 89 74 64 57 8 94 11 16 13 82 69 29 29 30 39 26 29 28 " 25 24 " 38 30 34 9 37 9 41 NA NA <1 0 <1 0 <1 0 <1 0 <1 0 <1 <1 <1 <1 <1 <1. <1 <1 <1 <1 <1 <1. <1 <1 <1 <1 <1 0 <1 0 <1 0 <1 0 <1 0 <"i o" <1 0 <1 0 2.8 1.1 1.6 27 NA NA <1 0 <1 0 <1"6 <1 0 <1.0 <1 0 <1 o" <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <10 <1 0 <1 0 <1 0 <1 0 <1.0 <1.0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1.0 <1 0 <1 0 <1 o" <1 0 <1.0 14.11 12.9 13.3' 73 " 59 47 61 5.7 51 49 50 44 07 46 49 52 5 2 62 59 54 5 1 90 90 100 100 90 46 63 "44 66 66 60 "56 89 (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 Monitoring Parameters Up To The 3rd Quarter 2013 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Carbon Tetrachloride (5 "9"-) Chloride No GWQS (mg/L) Chloroform (70 ug/L) IT; NA NA NA NA NA t,200 ifi2d 1*050 NA <5 0 NA <5 0 <50 81 <50 <50 86 <50 <50 116 <50 <50 123 <50 134 133 Did not sample 129 <1 o 132 <1 0 1:100 K600 ijfioo |jj&\990 iffeeoo W4'706 131 <1 0 128 <1.0 <1 0 113 12 124 <1 0 127 <1 0 1 2 132 <1 0 7ks& 43 <1 0 16 <1 0 124 1 3 mm <1 0 144 4 2 132 <1 0 49 142 <1 0 1 3 <1 0 146 17 135 <1 0 8.3 148 <1 0 21 <1 0 148 148 L2.200 <1 0 138 650 <1 0 1 1 149 <1 0 35 1950 <1 0 149 150 >1500 <1 0 164 10 <1 0 2;6M 571 <1.0 148 8,100 <1 0 179 Parameter GWQS Chloromethane (30 ug/L) Methylene Chloride (5 ug/L) Nitrate, Nitrate + Nitrite (10 mg/L) TW4-19 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) 12/5/11 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 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 <10 <1 0 <1 0 <1.0 <1 o" <1 0 <1 0 <1 0 "<1 0 <1 0 <1 0 <1 0 "<T o" <1 0 <1.0 <1.0 <1.0 <1 0 <1 0 <0.1 53 57 46 " 4 5 2 43 46 4 4 1 4 2 2 28 32 24 <0 1 w 2 4.4 59 ,2 7 ji 30 50 0""6 24 25 41 80 30 (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 3rd Quarter 2013 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Carbon Tetrachloride <5ug/L) NA NA <10 NA <250 <500 <500 <1000 3.1 2.2 35 13 15 NA 49 • 14 27 12 20 AO 10 33 25 Parameter GWQS Chloride No GWQS (mg/L) Chloroform <70 ug/L) Chloromethane <3Qug/L) Methylene Chloride (5 ug/L) Nitrate, Nitrate + Nitrite (10 mg/L) TW4-20 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 NA Monitor well was not installed M4 |^2J# ftpoo mm £5,200 Fiopo l^opp 18,000 24,000 i7v900: 11,000 36,d0fj 13,000 8,500™ 26^1) NA <10 <250 <500 <500 <1000 NA <10 29 <250 1 8 <500 38 <500 9 4 <1000 2 9 2 2 3 5 1.1 <1 0 4 2 <1 0 2 3 1.8 <1 0 2 1 <1 0 5 6 <1 0 09 <1 0 80 3 7 <1 0 4 4 NA NA 5 5 <1.0 5 1 4 2 <1 0 2 9 44 <1 0 33 <1 0 3 0 53 3 2 <1 0 2 0 <1.0 3 7 56 2 2 53 <1 0 <1 0 4 6 <1 0 4 4 <1 0 2 1 48 31 <1.0 6 5 25 <1 0 42 <1 0 7 9 <1 0 <1 0 108 <1.0 <1 0 <1 0 <1 0 vm 121 <i 0 91 13 <1.0 98 2 14 <1.0 8 7 (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 3rd 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 U9/L) Chloromethane 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 NA <5 0 <1 0 <2 5 <2 5 <2 5 <1 0 <1.0 2 1 8 5.8 1 7 1 6 NA <1 0 <1 0 <1 0 <1 0 NA NA NA Monitor well was not installed NA NA <5 0 <1 0 <2 5 <2 5 <2 5 <1 0 <1 <1 <1 <1 <1 <1 <1 NA <2 0 <1.0 <1 0 <1 0 <1 0 NA 14.6 10.1 9 6 85 89 87 8 7 86 86 8 3 m 88 7 57 80 "8 3 8.1 92 84 1st Qtr 2/25/10 2nd Qtr 614/10 3rd Qtr 8/13/10 4th Qtr 10/15/10 <1 0 <1 0 9.2 1.2 <1.0 <1 0 <1 0 <1 0 84 70 1st Qtr 2/22/11 2nd Qtr 6/28/11 3rd Qtr 8/17/11 4th Qtr 11/16/11 (t) 12/7/11 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 1 2 48 6 3 6.7 6\4 54 6 7 5.25 3.49 2 13 <1 0 <1 0 <1 0 <1 0 <1 o" <1 0 <1 0 <1.0 <1 0 <1 0 <1 0 90 il 3£8 (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 3rd Quarter 2013 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Parameter GWQS Carbon Tetrachloride Chloride No GWQS (mg/L) Chloroform (70 ug/L) Chloromethane (30 ug/L) Methylene Chloride (5 ug/L) Nitrate, Nitrate + Nitrite (10 mg/L) TW4-22 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 11/16711 (1> 12/7/1 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 NA <5 0 <5 0 <10 <10 <10 <1 0 <1 <1 <1 <1. <1 <1 NA <2.0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 o <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 1 3 1 2 3 24 3 35 3 25 NA NA NA Monitor well was not installed NA <5 0 <5 0 253 236 <10 <10 221 221 <10 236 <1 347 74 273 <1 259 <1 238 <1 1.4Q0; 519 <1 0 271 1,200 6,301 524 <1 539 NA NA <2 0 39 177 177 391 2,30 <1 38 175 427 134 340 130 <1 134 114 138 120 174 <1 0 36 <1 0 12 <1 0 35 <1 0 130 33 <1 0 10,60 <1 0 130 12,5 <1 0 586 9,64 <1 0 487 1 6 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 NA 15,3 m9. 19,3 I?-3 41S9 381 NA 2M1 ""36>i 11 mm 7 0 mm (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 3rd Quarter 2013 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Parameter GWQS Carbon Tetrachloride (5 "9"-) No Chloride GWQS (mg/L) Chloroform (70 "9/L) Chloromethane (30 ug/L) Methylene Chloride (5H9'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 <1.0 <1.0 <1 0 <L0 <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 b <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 <1 0 <1 0 <1 0 <1.0 <1 0 <1 0 NA <2 0 <1 o' <1 0 <1.0 <1 0 <1.0" <1 0 <1 0 <1 0 <1.0 <1.0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <ib <1 0 <1 0 NA <2 0 <1 0 <1 0 <1 0 <1.0 <1 o" <1 0 <1.0 <1 0 <1 0 <1 0 <1 0 <1 0 <1.0 <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 <0.1 <01 <0.1 <01 <0.1 <0 05 <0 05 NA <bi" <01 <01 <01 <oY <01 <01 <01 <01 <0 1 <01 <01 <01 <01 <0 1 <0.1 <0 1 0.1 <01 NA = not analyzed Shaded indicates concentrations exceeding GWQS TABLE 1 (25 of 27) Historic Summary Of Monitoring Parameters Up To The 3rd Quarter 2013 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Parameter GWQS Carbon Tetrachloride (5 ua/L) Chloride No GWQS (mg/L) Chloroform (7Q ug/D Chloromethane (30 ug/L) Methylene Chloride (5 ug/L) Nitrate, Nitrate + Nitrite (10 mg/L) M4 | 38f NA 305 -I30M pqf __:— 2.8j3 ^30 .31 .......» „,„ 31 C 34 '"*35 37 mm i35!9 33 TW4-24 2nd Qtr 6/27/07 3rd Qtr 8/15/07 4th Qtr 10/10/07 1stQtr3/28_/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 1 st 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 (1) 12/7/11 Tst 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 8/30/12 <1 0 <1.0 <1 0 <1 0" <1 0 <1 0 NA <2.0 <lY <1 0 <1 0 <1 0 <1 o" <1 0 <1 0 <1 0 <1 0 <1.0 <1 0 <1.0 <1 o" <1.0 <1 0 <1 0 <1 o' <1 0 <1 0 NA 770 791 692 740 834 1180 1130 T010 759 618 1080 896 639 587 522 1100 1110 967 608 "373" 355 489 405 1260 916 998 NA <2 0 <1 0 <1 0 <1 0 2.6 2.2 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 <1 0 <1.0 <1 0 <1 0 <1.0 <1 0 NA <2 0 <1.0 <1 0 <1 <1 <1 <1 <1 <1 <1 <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) 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 3rd 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 Mg/L) Chloromethane (30 ug/L) Methylene Chloride (5pg/L) Nitrate, Nitrate + Nitrite (10 mg/L) NA mm 33 WSJ; 9 04 5 24 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 9/4/12 <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 <i 0 <1.0 <1 o" <1 0 <1 0 <1 0 <1 o" <1 0 <1 0 NA 395 382 358 374 344 333 366 <1 0 <1 0 <f 0 <1.0 <1.0 NA <2 0 332 328 328 371 296 306 250 312 315 321 276 294 304 287 334 338 190 136 119 <1 0 <1 0 <1 0 <1 0 <1 0 <1.0 <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 8 <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 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) 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 3rd Quarter 2013 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Parameter GWQS Carbon Tetrachloride (Sua"-) Chloride No GWQS (mg/L) Chloroform (70 Mg/L) Chloromethane (30 ug/L) Methylene Chloride (5 ug/L) Nitrate, Nitrate + Nitrite (10 mg/L) TW4-26 2nd Qtr 6/14/10 " 3rd Qtr 8/24/10 4th Qtr 10/15/10 1st Qtr 2/16/11""" " 2nd Qtr 5/26/11 3rd Qtr 8/17/11 4th Qtr 11/16/11 (1) 12/7/1 1st Qtr f/18/12" 2nd Qtr 6/6/12 3rd Qtr 9/11/12 4th Qtr 10/3/12 1st Qtr2/7/13" 2nd Qtr 6/13/13 3rd Qtr 9/5/13 <1.0 <1 0 <1 0 <1 0 <1 0 <1 0 <1.0 <1 o" <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 33 17 22 30 15 19 26 17 19 19 19 16 6 14 5 176 13 52 54 2 2.9 28 52 7 4.1 4 9 49 49 2.12 2.81 <1 0 <1.0 <1.0 <1 0 <1.0 <1 0 <1 0 <1 0 <1 0 <1 0 <1.0 <1 0 <1 0 <1 0 <1.0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1.0 <1 0 <1 0 <1 0 7.9 9 96 10 10 P 10 11 «8S2 aW2 12 TW4-27 1st Qtr 1/18/12 2nd Qtr 6/13/12 3rd Qtr 9/4/12 4th Qtr 10/3/12 1st Qtr 2/7/13 2nd Qtr 6/13/13 3rd Qtr 8/30/13 <1.0 <1 0 <1 0 <1 0 <1 o" <1 0 <1 0 11 17 21 18 188 20.3 19 <1 0 <1.0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <l"6 <1 0 <1 0 <1.0 <1 0 <1 0 <1 0 <f 0 <1.0 <1 0 ma ^37 •sfef.36 TW4-28 2nd Qtr 6/19/13 3rd Qtr 8/29/13 <1.0 <1 0 44 6 45 3 <1.0 <1 0 <1 0 <1 0 <1 0 <1 0 TW4-29 2nd Qtr 6/19/13 2nd Qtr 7/11/13 3rd Qtr 9/26/13 <1 0 <1 0 <1 0 44 8 37 7 41 4 262 $6 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 46 3 5 4 TW4-30 2nd Qtr 6/19/13 3rd Qtr 9/26/13 <1 0 <1 0 36 36 3 <1.0 <1 0 <1 0 <1 0 <1 0 <1 0 1 0 1 TW4-31 2nd Qtr 6/19/13 3rd Qtr 9/5/13 <1 0 <1 0 28 4 29 4 <1 0 <1 0 <1.0 <1 0 <1 0 <1 0 1 3 Shaded indicates concentrations exceeding GWQS (1) VOCs were resampled because laboratory missed holding time. Table 2 Summary of QA/QC Samples 3rd Quarter 2013 Parameter GWQS Duplicate ofTW4-3 TW4-3 TW4-65 RPD Duplicate of TW4-8 TW4-8 TW4-70 RPD Nitrate + Nitrite (as N) 10 mg/L 6.26 5.98 4.6 <0.1 <0.1 Chloride none 24 24.2 -0.8 47.5 47.7 Chloroform 70 ug/L <1.0 <1.0 nc <1.0 <1.0 Carbon tetrachloride 5 Lig/L <1.0 <1.0 nc <1.0 <1.0 Chloromethane 30 ug/L <1.0 <1.0 nc <1.0 <1.0 Methylene Chloride 5 ug/L <1.0 <1.0 nc <1.0 <1.0 nc = not calculated Tabel 3 Chloroform Mass Removal Calculations DUSA White Mesa Mill, Bland, Utah 3rd 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 1,520 1.52E-03 3.36E-06 1.27E-05 72,899 0.93 0.08 2,940 2.94E-03 6.50E-06 2.46E-05 25,763 0.63 0.05 1,380 1 38E-03 3 05E-06 1.15E-05 63,515 0.73 0.06 8,100 8.10E-03 1 79E-05 6.77E-05 329,460 22.32 1.82 26,800 2.68E-02 5.92E-05 2.24E-04 19,731 4.42 0.36 9,640 9.64E-03, 2.13E-05 8.06E-05 25,593 2.06 0.171 22 2.18E-05 4.82E-08 1.82E-07 267,704 0.05 6.004 0.00E+00 0.00E+00 0.00E+00 145,841 0.00 0 00 total lbs of chloroform removed 31.14 total gallons of chloroform removed 2.53 -