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Home My WebLink AboutDRC-2016-005641 - 0901a0688061ce33LLRW/U-Nlill Document Scanning Form Document Type Incomlngj^^^j Outgoing] DRC Program LLRWl I GS/ internal] U-Milll Facility/License # _ Document Date i /r~2_0"' / £ IrUsffs Document Title Please Authors)Lka/i U&h Check Applicable Folder Selection Application|__| Correspondenci Compliance! y. \ Licensel Check Applicable Document Class Analytical!*""-I Fi Email! inspection Report GW Permi Other Letter Monitoring Report A/-emo> P K C - zOig - 0 0 5 ^ 4 1 f,T I\4 x«: •-V./896 State of Utah GARY R. HERBERT Governor SPENCER J. COX Lieutenant Governor Department of Environmental Quality Alan Matheson Executive Director DIVISION OF WASTE MANAGEMENT AND RADIATION CONTROL Scott T. Anderson Director DKc- to\b- oo s^4-l MEMORANDUM f/x/j' TO: Phil Goble fib FROM: Dean Henderson ^ fai //& DATE: January 20,2016 SUBJECT: Review of the 3rd Quarter 2015 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 Waste Management and Radiation Control (“Division”) has reviewed the November 20,2015 3rd Quarter 2015 Chloroform Monitoring Report (“Report”) for the Chloroform Contamination Investigation. For the review of this report the following regulatory enforcement documents were used: • EFR issued Ground Water Quality Discharge Permit No. UGW370004 (“Permit”). Permit version that was signed on August 24,2012. • The EFR Quality Assurance Plan (“QAP”) June 7,2012 (Revision. 7.2) • The EFR Groundwater Corrective Action Plan (“GCAP”) September 14,2015 (Revision 0) REVIEW Monitor Well Sampling The following monitor wells were sampled as required in the QAP (see Table 1 below): MW-4 MW-26 MW-32 TW4-1 TW4-2 TW4-3 TW4-7 TW4-8 TW4-9 TW4-10 TW4-11 TW4-12 TW4-18 TW4-19 TW4-20 TW4-21 TW4-22 TW4-23 TW4-28 TW4-29 TW4-30 TW4-31 TW4-32 TW4-33 195 North 1950 West • Salt Lake City, UT Mailing Address: P.O. Box 144880 • Salt Lake City, UT 84114-4880 Telephone (801) 536-0200 • Fax (801) 536-0222 • T.D.D. (801) 5364414 www.deq.utah.goo Printed on 100% recycled paper Page 2 TW4-4 TW4-13 TW4-24 TW4-34 TW4-5 TW4-14 TW4-25 TW4-35 TW4-6 TW4-16 TW4-26 TW4-36 TW4-27 TW4-37 In each quarter the monitoring wells were purged using the three approved QAP well purging strategies and meet QAP requirements for each strategy: 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, TW4-5, TW4-8, TW4-9, TW4-16, TW4-18, TW4-23, 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: TW4-3, TW4-6, TW4-7, TW4-10, TW4-12, TW4-13, TW4-14, TW4-26, TW4-27, TW4- 28, TW4-29, TW4-30, TW4-31, TW4-33, TW4-34, TW4-35 and TW36. 3. Pumping Wells: MW-4, MW-26, TW4-1, TW4-2, TW4-4, TW4-11, TW4-19, TW4-20, TW4- 21, TW4-22, TW4-24, TW4-25, and TW4-37. 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 + Nitrite as Nitrogen. The analytical methods used is consistent with the requirements of the QAP requirements. QA/QC 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. Page 3 Sample Duplicates Two duplicate samples were collected. Monitor well TW4-12 and its duplicate sample TW4-65 and TW4-23 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). 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: • The quarterly groundwater compliance monitoring wells. • Existing monitoring well MW-4 and all of the temporary chloroform investigation wells. • Piezometers P-1, 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, TW4-1, TW4-2, TW4-4, TW4-11, TW4-19, TW4-20, TW4-21, TW4-22, TW4-24, TW4-25, TW4-37 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 the 3rd Quarter, 2015 is 33.4 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. Page 4 -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. d) Conclusions and Recommendations e) Electronic copy of all laboratory results for Chloroform Investigation monitoring conducted during the quarter. f) Copies of DUS A 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 up to the 3rd Quarter, 2015 monitoring event appeared to show that the chloroform contaminate plume (“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). Monitor Wells Exceeding Chloroform Concentrations GWOS of 70pg/L Six monitor wells: TW4-6, TW4-7, TW4-8, TW4-10, TW4-16, TW4-29, and TW4-33. Monitor Wells with Chloroform Concentrations between 1 pg/L and 70ug/L Eight monitor wells: TW4-5, TW4-9, TW4-18, TW4-26, TW4-26, and TW4-27 For the first time since sampling began (1st quarter 2012) at well TW4-27 it exceeded the chloroform minimum detection limit of <1.0 pg/L at 1.3 pg/L (see Table 1 below). TW4-27 helps define the eastern southern boundary area of the Plume and is located approximately 200 feet east and down gradient of TW4-33 that as of this 3rd quarter monitoring event has a reported chloroform concentration of 123 pg/L (see Table 1 below). No action is recommended but a close watch on this monitor well will be done to see if chloroform increases to above 70 pg/L. For the third consecutive monitoring event well TW4-30 has exceeded the chloroform minimum detection limit of <1.0 pg/L of 3.27 pg/L (see Table 1 below). TW4-30 helps define the southern boundary area of the Plume and is located approximately 200 feet east and down gradient of TW4-29 that as of the 3rd quarter 2015 monitoring event has a reported chloroform concentration of 276 pg/L (see Table 1 below). The leading edge of Plume may be approaching TW4-30. No action is Page 5 recommended but a close watch on this monitor well be done to see if chloroform increases to above 70 Pg/L. Pumping Wells Pumping wells MW-4, MW-26, TW4-1, TW4-2, TW4-4, TW4-11, TW4-19, TW4-20, TW4-21 TW4-22 and TW4-37 exceed chloroform concentrations of 70pg/L. Pumping well TW4-24 had a chloroform concentration of 46.9 pg/L and TW4-25 had non-detectable chloroform concentrations (<1.0 pg/L). Monitor Wells Below the Laboratory Chloroform Detection Limit (<1.0 pg/Ll The following monitor wells are below the laboratory detection limit for chloroform (<1.0 pg/L): MW- 32, TW4-3, TW4-12, TW4-13, TW4-14, TW4-23, TW4-28, TW4-31, TW4-32, TW4-34, TW4-35 and TW4-36. Nitrate. Nitrate + Nitrite (“nitrate”) Concentrations Monitor wells TW4-21, TW4-22, and TW4-24 all exceed the nitrate GWQS of 10 mg/1. 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. Conclusions on Compliance with the Permit and QAP Per the Division review it appears that the Reports comply with Permit, QAP, and GCAP. Therefore a letter will be drafted for the Director Signature, notifying EFR of the review and closing out of 3rd Quarter 2015 Chloroform Monitoring Report for the chloroform contamination investigation. TABLE 1 (1 of 27) Historic Summary Of Monitoring Parameters Up To The 3rd Quarter 2015 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Carbon Tetrachloride ______(spg/L)______ Chloroform (70 ug/L) Chloromethane (30 pg/L) Parameter (GWQS) Methylene Chloride (5 pg/L) Chloride No GWQS (mg/L) Nitrate, Nitrate + Nitrite ______(10 mg/L)______ MW-4 (chloroform pumping well) 1st Qtr 3/16/05 2nd Qtr 5/25/05 3rd Qtr 8/31/05 4th Qtr 12/7/05 NA NA <10 <50 2,900 3,170 3,500 3,000 NA NA <10 <50 NA NA <10 <50 NA NA NA 53 6.3 7.1 7.0 7.0 1st Qtr 3/9/06 2nd Qtr 6/14/06 3rd Qtr 7/20/06 4 th Qtr 11/8/06 <50 <50 <50 2.1 3,100 3,000 2,820 2,830 <50 <50 <50 1.4 <50 <50 <50 <1.0 49 49 48 50 6.0 6.0 1.2 6.4 1st Qtr 2/28/07 2nd Qtr 6/27/07 3rd Qtr 8/15/07 4th Qtr 10/10/07 1.6 1.8 1.9 1.7 2,300 2,000 2,600 2,300 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 47 45 47 45 6.3 7.0 6.2 6.2 1st Qtr 3/28/08 2nd Qtr 6/25/08 3rd Qtr 9/10/08 4th Qtr 10/15/08 1.7 1.8 1.8 1.7 2,400 2,500 1,800 2,100 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 42 42 35 45 5.8 6.1 6.4 5.9 1st Qtr 3/4/09 2nd Qtr 6/23/09 3rd Qtr 9/14/09 4th Qtr 12/14/09 1.5 1.3 1.4 1.6 2,200 1,800 2,000 1,800 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 37 34 43 44 5.7 5.2 5.3 5.8 1st Qtr 2/17/10 2nd Qtr 6/14/10 3rd Qtr 8/6/10 4th Qtr 10/15/10 1.2 1.2 1.5 1.4 1,600 2,100 1,900 1,500 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 45 41 38 41 4.0 5.1 4.8 4.9 1st Qtr 2/23/11 2nd Qtr 6/1/11 3rd Qtr 8/17/11 4th Qtr 11/16/11 1.5 1.4 1.1 1.3 1,700 1,700 1,700 1,600 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 40 35 41 40 4.6 4.9 4.9 5.1 1st Qtr 1/23/12 2nd Qtr 6/6/12 3rd Qtr 9/4/12 4th Qtr 10/4/12 1 1.2 1.5 1 1,500 1,400 1,500 1,300 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 41 39 41 41 4.8 4.9 5.0 4.8 1st Qtr 2/11/13 2nd Qtr 6/5/13 3rd Qtr 9/3/13 4th Qtr 10/29/13 1.48 1.31 1.13 5.58 1,670 1,490 1,520 1,410 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 37.8 44 41.4 40.1 4.8 4.2 4.9 5.3 1st Qtr 1/27/14 2nd Qtr 5/19/14 3rd Qtr 8/11/14 4th Qtr 10/21/14 4.15 5.21 7.6 <1.0 1,390 1,390 1,490 1,440 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 38.5 39.9 41 41.5 4.7 4.1 3.7 5.1 1st Qtr 3/9/15 2nd Qtr 6/8/15 3rd Qtr 8/31/14 1.26 <1.0 <1.0 1,400 1,300 1,200 <1.0 <1.0 1.42 <1.0 <1.0 <1.0 40.7 43.1 44.3 5.8 2.5 4.79 MW-4A(TW4-A) 1st Qtr 3/16/05 2nd Qtr 5/25/05 3rd Qtr 8/31/05 4th Qtr 12/7/05 NA NA <10 <50 3,700 3,740 3,800 3,000 NA NA <10 <50 NA NA <10 <50 NA NA NA 55 7.1 7.8 6.9 6.7 1st Qtr 3/9/06 2nd Qtr 6/14/06 3rd Qtr 7/20/05 4th Qtr 11/8/05 <50 <50 <50 2.4 3,700 3,300 3,190 3,370 <50 <50 <50 <1.0 <50 <50 <50 <1.0 53 54 54 54 5.8 7.3 1.2 7.1 7.11st Qtr 2/28/07 1.9 2,500 <1.0 <1.0 Well abandonded 60 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 2015 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Carbon Tetrachloride ______(5M9/L)______ Chloroform (70 pg/L) Chloromethane ___(30 ug/L)___ Parameter (GWQS) Methylene Chloride (5 ug/L) Chloride No GWQS (mg/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 NA NA <5.0 <50 310 442 960 1,000 NA NA 5.4 <50 NA NA <5.0 <50 NA NA NA 55 0.3 0.2 0.2 0.3 0.2 0.2 1.4 0.3 0.6 0.4 1 0.66.1 0.6 0.2 0.1 1st Qtr 3/9/06 2nd Qtr 6/14/06 3rd Qtr 7/20/06 4th Qtr 11/8/06 <50 <50 <50 <1.0 1,100 830 2,170 282 <50 <50 <50 <1.0 <50 <50 <50 2.6 52 52 65 54 1st Qtr 2/28/07 2nd Qtr 6/27/07 3rd Qtr 8/15/07 4th Qtr 10/10/07 <1.0 <1.0 <1.0 <1.0 570 300 1,400 2,000 <1.0 <1.0 <1.0 <1.0 5.5 13 36 14 56 49 57 57 1st Qtr 3/28/08 2nd Qtr 6/25/08 3rd Qtr 9/10/08 4th Qtr 10/15/08 11/18/08 <1.0 <1.0 <1.0 NA <2.0 NA 930 1,300 630 1,700 <1.0 <1.0 <1.0 NA <2.0 NA 40 53 24 100 49 57 44 64 NA NA 1st Qtr 3/4/09 2nd Qtr 6/23/09 3rd Qtr 9/14/09 4th Qtr 12/14/09 <1.0 <1.0 <1.0 <1.0 950 410 850 1,100 <1.0 <1.0 <1.0 <1.0 51 12 30 40 49 48 46 60 1st Qtr 2/17/10 2nd Qtr 6/14/10 3rd Qtr 8/16/10 4th Qtr 10/15/10 <1.0 <1.0 <1.0 1.2 730 1,600 2,200 970 <1.0 <1.0 <1.0 <1.0 <1.0 19 21 6.5 57 40 49 65 0.4 0.2 0.1 2.36.2 6.8 0.6 0.7 6.5 0.4 09 2.0 NA 1.7 2.5 2.6 1.8 2.3 2.1 1.2 1 4 6.5 0.9 0.7 0.9 6.7 0.4 0.7 1st Qtr 2/23/11 2nd Qtr 5/31/11 3rd Qtr 8/17/11 4th Qtr 11/16/11 (1)12/5/11 <1.0 <1.0 <1.0 NA <1.0 450 1,800 720 NA 1,800 <1.0 <1.0 <1.0 NA <1.0 3.6 1.3 7.2 NA 2.9 57 88 58 69 NA 1st Qtr 2/7/12 2nd Qtr 6/6/12 3rd Qtr 9/4/12 4th Qtr 10/4/12 <1.0 <1.0 <1 <1 2,400 3,000 3,100 1,200 <1.0 <1.0 <1 <1 16 21 31 4 98 73 73 68 1st Qtr 2/11/13 2nd Qtr 6/5/13 3rd Qtr 9/3/13 4th Qtr 10/29/13 <1 <1.0 <1.0 <1.0 2,120 4,030 2,940 1,410 <1 <1.0 <1.0 <1 9.34 52.4 33.2 4.03 81.9 77.9 60.5 72.3 1st Qtr 1/27/14 2nd Qtr 5/19/14 3rd Qtr 8/11 /14 4th Qtr 10/21/14 <1.0 <1.0 <1.0 <1.0 1,400 1,960 2,120 2,090 1st Qtr 3/9/15 2nd Qtr 6/8/15 3rd Qtr 8/31/14 <1.0 <1.0 <1.0 1,980 1,980 2,350 <1.0 <1.0 <1.0 <1.0 <1.0 8.7 4.05 13.8 15.4 26 23.2 59.4 53.4 59 60.1 27.4 11.2 11.6 56.5 62 69.6 (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 2015 Chloroform Contamination Investigation DUSA White Mesa Mill Weli Sampling Event Carbon Tetrachloride (5 pg/L) Chloroform (70 H9/L) Chloromethane (30 M9/L) Parameter (GWQS) Methylene Chloride (5 pg/L) Chloride No GWQS (mg/L) Nitrate, Nitrate + Nitrite (10 mg/L) MW-32 (former TW4- 1st Qtr 3/16/05 2nd Qtr 5/25/05 3rd Qtr 8/31/05 4th Qtr 12/7/05 -17) NA NA <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 NA NA <1.0 3.2 NA NA <1.0 <1.0 NA NA NA 33 <0.1 <0.1 <0.1 <0.1 1st Qtr 3/9/06 2nd Qtr 6/14/06 3rd Qtr 7/20/06 4th Qtr 11/8/06 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 3.5 1.8 1.5 <1.0 <1.0 <1.0 <1.0 32 30 32 31 <0.1 <0.1 <1,0 <1 1st Qtr 2/28/07 2nd Qtr 6/27/07 3rd Qtr 8/15/07 4th Qtr 10/10/07 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 1st Qtr 3/28/08 2nd Qtr 6/25/08 3rd Qtr 9/10/08 4th Qtr 10/15/08 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 31 29 30 26 <.1 <1.0 <1.0 <0.05 1st Qtr 3/4/09 2nd Qtr 6/23/09 3rd Qtr 9/14/09 4th Qtr 12/16/09 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 30 31 33 35 <.1 <0.1 <0.1 <0.1 1st Qtr 2/17/10 2nd Qtr 6/14/10 3rd Qtr 8/16/10 4th Qtr 10/15/10 <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 38 32 28 24 <0.1 <0.1 <0.1 <0.1 1st Qtr 2/23/11 2nd Qtr 5/25/11 3rd Qtr 8/16/11 4th Qtr 11/16/11 <1) 12/7/1 <1.0 <1.0 <1.0 NA <1.0 <1.0 <1.0 <1.0 NA <1.0 <1.0 <1.0 <1.0 NA <1.0 <1.0 <1.0 <1.0 NA <1.0 NA 40 31 33 32 <0.1 <0.1 <0.1 <0.1 NA 1st Qtr 1/18/12 2nd Qtr 6/22/12 3rd Qtr 9/5/12 4th Qtr 10/10/12 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 21 32 33 35 <0.1 <0.1 <0.1 <0.1 1st Qtr 2/11/13 2nd Qtr 6/18/13 3rd Qtr 9/3/13 <1.0 <1.0 <1.0 4th Qtr 10/29/13 <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 34.3 34.9 33 35.7 <0.1 <0.1 <0.1 <0.1 1st Qtr 1/29/14 2nd Qtr 5/23/14 <1.0 <1.0 3rd Qtr 8/26 /14 4th Qtr 10/29/14 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 34 39.7 34 34.9 <0.1 <0.1 <0.1 <0.1 1st Qtr 3/17/15 2nd Qtr 6/11/15 3rd Qtr 9/9/15 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 36.3 35.8 37.7 <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 3rd Quarter 2015 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Carbon Tetrachloride My______ Chloroform (70M9/L) Chloromethane (30 Ufl/L) Parameter (GWQS) Methylene Chloride ______(5M9/L)______ Chloride No GWQS (mg/L) Nitrate, Nitrate + Nitrite _______(10 mg/L)______ TW4-1 (chloroform pumping well) 1st Qtr 3/16/05 2nd Qtr 5/25/05 3rd Qtr 8/31/05 4th Qtr 12/7/05 NA NA <10 <50 2,700 3,080 2,900 2,400 NA NA <10 <50 NA NA <10 <50 NA NA NA 52 9.1 10.6 9.8 9.7 1st Qtr 3/9/06 2nd Qtr 6/14/06 3rd Qtr 7/20/06 4th Qtr 11/8/06 <50 <50 <50 1.4 2,700 2,200 2,840 2,260 <50 <50 <50 <1.0 <50 <50 <50 <1.0 49 48 51 47 9.4 9.6 9.2 1st Qtr 2/28/07 2nd Qtr 6/27/07 3rd Qtr 8/15/07 4th Qtr 10/10/07 1.2 1.4 1.3 1.3 1,900 1,900 2,300 2,000 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 47 45 43 43 8.9 9 8.4 7.8 1st Qtr 3/28/08 2nd Qtr 6/25/08 3rd Qtr 9/10/08 4th Qtr 10/15/08 1.3 1.1 1.3 1.3 2,000 1,900 1,700 1,700 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 39 39 35 41 7.6 8.68 8.15 9.3 1st Qtr 3/11/09 2nd Qtr 6/23/09 3rd Qtr 9/14/09 4th Qtr 12/29/09 <1.0 <1.0 1.1 1 1,700 1,500 1,700 1,400 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 37 37 36 41 7.5 6.9 7.3 6.8 1st Qtr 3/3/10 2nd Qtr 6/14/10 3rd Qtr 8/18/10 4 th Qtr 10/15/10 <1.0 <1.0 1.2 1 1,300 1,600 1,600 1,500 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 35 40 35 40 7.1 6.8 6.7 6.6 6.6 6.6 6.8 6.6 6.8 7.1 5.0 6.5 7.0 6.9 7.1 7.1 7.7 6.9 4.8 6.3 7.1 6.1 6.3 1st Qtr 2/24/11 2nd Qtr 6/1/11 3rd Qtr 8/18/11 4th Qtr 11/29/11 <1.0 <1.0 <1.0 <1.0 1,300 1,200 1,300 1,500 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 41 35 36 40 1st Qtr 1/24/12 2nd Qtr 6/14/12 3rd Qtr 9/28/12 4th Qtr 10/4/12 <1.0 <1.0 <1.0 <1.0 1,300 1,000 1,000 1,100 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 38 42 39 40 1st Qtr 2/13/13 2nd Qtr 6/19/13 3rd Qtr 9/3/13 4th Qtr 11/14/13 <1.0 <1.0 <1.0 3.66 1,320 1,100 1,150 1,280 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 37.6 39.1 37.6 36.5 1st Qtr 2/5/14 2nd Qtr 5/23/14 3rd Qtr 8/27/14 4th Qtr 10/29/14 <1.0 <1.0 5.47 4.77 1,090 1,020 845 1,140 <1.0 <1.0 <1.0 1.4 <1.0 <1.0 <1.0 <1.0 38.9 37.4 38 38.7 1st Qtr 3/9/15 2nd Qtr 6/8/15 3rd Qtr 8/31/15 <1.0 <1.0 <1.0 1,130 1,260 1,060 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 38.3 40.3 45.9 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 2015 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Carbon Tetrachloride (5ug/L) Chloroform (70 pg/L) Chloromethane (30 pg/L) Parameter (GWQS) Methylene Chloride (S pg/L) Chloride No GWQS (mg/L) Nitrate, Nitrate + Nitrite (10 mg/L) TW4-2(chloroform pumping well) 1st Qtr 3/16/05 2nd Qtr 5/25/05 3rd Qtr 8/31/05 4th Qtr 12/7/05 NA NA <10 <50 3,700 3,750 3,900 3,500 NA NA <10 <50 NA NA <10 <50 NA NA NA 56 7.7 8.6 8.0 7.8 7.5 7.1 7.4 7.6 7.3 7.8 7.3 6.9 6.9 7.4 7.1 8.0 1st Qtr 3/9/06 2nd Qtr 6/14/06 3rd Qtr 7/20/06 4th Qtr 11/8/06 <50 <50 <50 2.3 3,800 3,200 4,120 3,420 <50 <50 <50 <1.0 <50 <50 <50 <1.0 56 56 54 55 1st Qtr 2/28/07 2nd Qtr 6/27/07 3rd Qtr 8/15/07 4th Qtr 10/10/07 1.8 2.5 2.2 2.1 2,300 3,000 340 (?) 3,200 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 54 50 49 51 1st Qtr 3/28/08 2nd Qtr 6/25/08 3rd Qtr 9/10/08 4th Qtr 10/15/08 11/18/08 NA 2.3 2.2 2.4 2.4 NA 3,300 3,100 2,800 3,200 <1.0 <1.0 <1.0 NA <2.0 <1.0 <1.0 <1.0 NA <2.0 NA 48 46 42 47 NA 1st Qtr 3/11/09 2nd Qtr 6/23/09 3rd Qtr 9/14/09 4th Qtr 12/29/09 2.2 2 2 2 3,100 2,800 3,000 1,600 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 46 44 43 46 6.5 6.4 6.6 6.4 6.8 8.7 6.6 6.5 7.6 6.8 6.0 7.0 7.1 7.7 4.0 7.6 8.1 7.5 9.3 8.4 7.9 9.1 6.2 8.5 5.3 4.3 3.8 1st Qtr 3/3/10 2nd Qtr 6/14/10 3rd Qtr 8/18/10 4th Qtr 10/15/10 2 2.6 2.5 2.1 2,600 3,300 3,300 3,000 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 42 43 43 41 1st Qtr 2/24/11 2nd Qtr 6/2/11 3rd Qtr 8/17/11 4th Qtr 11/29/11 2.4 2.2 1.6 2.8 3,100 3,000 2,400 3,900 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 46 42 48 49 1st Qtr 1/24/12 2nd Qtr 6/14/12 3rd Qtr 9/28/12 4th Qtr 10/4/12 2 2.1 1.8 2 2,500 2,500 2,900 3,100 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 49 52 76 49 1st Qtr 2/13/13 2nd Qtr 6/19/13 3rd Qtr 9/3/13 4th Qtr 11/14/13 5.17 2.65 2.41 3.15 3,580 3,110 3,480 3,740 <1.0 2 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 46 46.9 44.9 43.9 1st Qtr 2/6/14 2nd Qtr 5/23/14 3rd Qtr 8/27/14 4th Qtr 10/30/14 7.1 6.05 1.4 2.6 3,180 2,930 3,170 3,580 <1.0 <1.0 <1.0 3.6 <1.0 <1.0 <1.0 <1.0 45.9 45.4 45 45.5 1st Qtr 3/9/15 2nd Qtr 6/8/15 3rd Qtr 8/31/15 <1.0 <1.0 1.44 1,840 1,650 1,060 <1.0 <1.0 2.6 <1.0 <1.0 <1.0 44.9 48.1 50 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 2015 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Carbon Tetrachloride (5 ug/L) Chloroform (70 M9/L) Chloromethane (30 ng/L) Parameter (GWQS) Methylene Chloride ______(5 M9/L)_____ Chloride No GWQS (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 NA NA <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 NA NA <1.0 6.4 NA NA <1.0 <1.0 NA NA NA 26 3.5 3.7 3.5 3.3 1st Qtr 3/9/06 2nd Qtr 6/14/06 3rd Qtr 7/20/06 4th Qtr 11/8/06 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 2.3 1.6 2.2 <1.0 <1.0 <1.0 <1.0 <1.0 26 26 26 23 3.3 7.1 2.9 1.5 3.1 3.3 3.1 2.8 2.8 2.9 2.7 2.6 2.5 2.9 2.8 2.6 2.83.6 3.1 3.3 3.5 3.7 4.0 4.4 7.1 4.4 4.9 4.8 5.1 5.8 4.9 5.9 6.7 6.0 5.3 6.1 6.6 5.7 3.9 3.9 1st Qtr 2/28/07 2nd Qtr 6/27/07 3rd Qtr 8/15/07 4th Qtr 10/10/07 <1.0 <1.0 <1.0 <1.0 <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 23 24 27 1st Qtr 3/28/08 2nd Qtr 6/25/08 3rd Qtr 9/10/08 4th Qtr 10/15/08 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 21 19 19 22 1st Qtr 3/4/09 2nd Qtr 6/23/09 3rd Qtr 9/14/09 4th Qtr 12/29/09 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 21 20 21 22 1st Qtr 2/23/10 2nd Qtr 6/14/10 3rd Qtr 8/10/10 4 th Qtr 10/15/10 <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 23 24 22 26 1st Qtr 2/15/11 2nd Qtr 5/25/11 3rd Qtr 8/16/11 4th Qtr 11/14/11 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 23 23 23 23 1st Qtr 1/17/12 2nd Qtr 5/31/12 3rd Qtr 8/29/12 4th Qtr 10/3/12 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 21 24 25 25 1st Qtr 2/7/13 2nd Qtr 6/29/13 3rd Qtr 9/3/13 4th Qtr 11/6/13 <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 23.7 23.8 25 24.1 1st Qtr 1/22/14 2nd Qtr 5/21/14 3rd Qtr 8/13/14 4th Qtr 10/23/14 <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 24.9 24.4 26 26.7 1st Qtr 3/11/15 2nd Qtr 6/10/15 Duplicate TW4-65 3rd Qtr 8/13/14 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 26.2 27.5 27.5 27.4 NA = not analyzed Shaded indicates concentrations exceeding GWQS. TABLE 1 (7 of 27) Historic Summary Of Monitoring Parameters Up To The 3rd Quarter 2015 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Carbon Tetrachloride (5 H9/L) Chloroform (70 M9/L) Chloromethane (30 pg/L) Parameter (GWQS) Methylene Chloride (5 pg/L) Chloride No GWQS (mg/L) Nitrate, Nitrate + Nitrite (10 mg/L) TW4-4 (chloroform pumping well) 1st Qtr 3/16/05 2nd Qtr 5/25/05 3rd Qtr 8/31/05 4th Qtr 12/7/05 NA NA <10 <50 1st Qtr 3/9/06 2nd Qtr 6/14/06 3rd Qtr 7/20/06 4th Qtr 11/8/06 <50 <50 <50 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 NA <2.0 3,100 2,400 3,200 2,800 1.7 2,900 2,600 2,850 2,670 NA NA <10 <50 <50 <50 <50 <1.0 NA NA <10 <50 <50 <50 <50 <1.0 1.5 1.7 1.5 1.5 2,200 2,400 2,700 2,500 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 1.6 1.5 1.4 NA 2,800 2,500 2,200 2,500 <1.0 <1.0 <1.0 NA <2.0 <1.0 <1.0 <1.0 NA <2.0 NA NA NA NA 54 51 48 50 49 49 47 45 47 43 42 39 44 NA 10.0 11.3 9.9 10.2 9.5 8.6 9.7 10.1 9.0 9.4 9.5 9.5 9.2 10.8 8.8 10.1 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 1.2 1.2 1.1 1.1 2,200 1,800 2,000 950 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 1 1.2 1.3 1.3 1,700 1,700 2,100 1,700 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 37 34 39 41 48 35 36 38 10.2 8.2 8.4 7.6 6.6 7.6 7.3 7.1 1st Qtr 2/23/11 2nd Qtr 6/1/11 3rd Qtr 8/17/11 4th Qtr 11/16/11 <1.0 1.4 1.2 1,800 1,700 1,500 1,500 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 41 35 40 39 7.0 7.0 6.6 7.0 7.1 7.1 7.1 7.0 7.4 6.3 7.2 7.8 7.3 5.9 5.3 7.0 . ....... 6.3 6.5 1st Qtr 1/23/12 2nd Qtr 6/6/12 3rd Qtr 9/4/12 4th Qtr 10/3/12 <1.0 <1.0 1st Qtr 2/11/13 2nd Qtr 6/29/13 3rd Qtr 9/3/13 4th Qtr 10/3/13 <1.0 1st Qtr 1/27/14 2nd Qtr 5/19/14 3rd Qtr 8/11/14 4th Qtr 10/21/14 <1.0 1.2 1 1,200 1,500 1,600 1,400 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 1.2 5.3 1,460 1,330 1,380 1,360 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 3.88 4.94 4.94 1,260 1,220 1,320 1,130 <1.0 <1.0 <1.0 7.1 <1.0 <1.0 <1.0 <1.0 38 43 39 38 39 39.6 38.8 43.9 37.4 47.5 40 40 1st Qtr 3/9/15 2nd Qtr 6/10/15 3rd Qtr 8/31/15 <1.0 <1.0 1.05 1,350 1,280 1,220 <1.0 <1.0 1.72 <1.0 <1.0 <1.0 37.6 41.3 45.8 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 2015 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Carbon Tetrachloride (5 pg/L) Chloroform (70 ua/L) Chloromethane ___(30 pg/L)___ Parameter (GWQS) Methylene Chloride (5 pg/L) Chloride No GWQS (mg/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 NA NA <2.5 <2.5 120 113 82 63 NA NA 5.8 2.5 NA NA <2.5 <2.5 NA NA NA 56 4.9 3.7 6.0 6.0 1st Qtr 3/9/06 2nd Qtr 6/14/06 3rd Qtr 7/20/06 4th Qtr 11/8/06 <2.5 <2.5 <1.0 <1.0 66 51 53.7 47.1 3.1 3.1 <1.0 <1.0 <2.5 <2.5 <1.0 <1.0 52 51 54 55 6.0 5.9 6.7 2.9 7.8 7.0 7.7 8.2 7.4 8.7 7.9 9.3 7.9 7.5 8.3 7.5 6.8 7.1 7.0 7.2 7.6 7.2 7.5 6.0 1st Qtr 2/28/07 2nd Qtr 6/27/07 3rd Qtr 8/15/07 4th Qtr 10/10/07 <1.0 <1.0 <1.0 <1.0 35 26 9.2 9.4 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 57 45 38 39 1st Qtr 3/28/08 2nd Qtr 6/25/08 3rd Qtr 9/10/08 4th Qtr 10/15/08 <1.0 <1.0 <1.0 <1.0 11 9.3 11 10 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 36 37 34 37 1st Qtr 3/4/09 2nd Qtr 6/23/09 3rd Qtr 9/14/09 4th Qtr 12/29/09 <1.0 <1.0 <1.0 <1.0 12 13 12 8.5 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 34 37 48 41 1st Qtr 2/25/10 2nd Qtr 6/14/10 3rd Qtr 8/11/10 4th Qtr 10/15/10 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 43 28 38 41 1st Qtr 2/22/11 2nd Qtr 5/26/11 3rd Qtr 8/7/11 4th Qtr 11/16/11 (1) 12/7/11 <1.0 <1.0 <1.0 NA <1.0 NA 10 9 10 7.9 <1.0 <1.0 <1.0 NA <1.0 <1.0 <1.0 <1.0 NA <1.0 NA 34 35 37 30 NA 1st Qtr 1/18/12 2nd Qtr 6/6/12 3rd Qtr 9/11/12 4th Qtr 10/3/12 <1.0 <1.0 <1.0 <1.0 7.6 8.4 12 8 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 22 39 37 38 5.8 8.0 8.1 7.7 1st Qtr 2/13/13 2nd Qtr 6/13/13 3rd Qtr 9/5/13 4th Qtr 11/13/13 <1.0 <1.0 <1.0 <1.0 10.8 11.2 11.6 14.4 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 34.3 36.5 39.1 41.1 8.2 10.7 7.8 7.8 1st Qtr 1/30/14 2nd Qtr 5/22/14 3rd Qtr 8/14/14 4th Qtr 11/13/13 <1.0 <1.0 <1.0 <1.0 12.5 13.4 12.0 14.6 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 40.5 51.4 44 45.1 9.2 7.8 7.2 8.3 1st Qtr 3/12/15 Duplicate TW4-70 2nd Qtr 6/10/15 3rd Qtr 9/3/15 <1.0 <1.0 <1.0 <1.0 13.8 13.8 13.3 12.9 <1.0 <1.0 1.07 <1.0 <1.0 <1.0 <1.0 <1.0 45.1 46.4 47.3 52.2 9.3 8.8 7.1 8.1 (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 2015 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Carbon Tetrachloride ______(5Mg/L)______ Chloroform (70 pg/L) Chloromethane ___(30 M9/L)___ Parameter (GWQS) Methylene Chloride ______(spg/L)_____ Chloride No GWQS (mg/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 NA NA <1.0 <1.0 <1.0 2.5 10 17 NA NA 2.8 1.3 NA NA <1.0 <1.0 NA NA NA 32 0.2 0.4 0.8 0.9 1.2 1.0 0.6 1.4 1.8 0.6 0.7 0.8 1.1 0.9 1.1 1.0 2.2 2.7 5.0 6.1 1.8 2.5 3.9 4.3 0.7 0.3 0.3 0.8 NA 0.8 6.7 0.2 0.1 0.2 6.2 0.2 0.2 1.5 6.2 0.3 4.2 6.9 1st Qtr 3/9/06 2nd Qtr 6/14/06 3rd Qtr 7/20/06 4th Qtr 11/8/06 <1.0 <1.0 <1.0 <1.0 31 19 11 42.8 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 31 30 37 65 1st Qtr 2/28/07 2nd Qtr 6/27/07 3rd Qtr 8/15/07 4th Qtr 10/10/07 <1.0 <1.0 <1.0 <1.0 46 11 18 18 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 32 38 36 35 1st Qtr 3/28/08 2nd Qtr 6/25/08 3rd Qtr 9/10/08 4th Qtr 10/15/08 <1.0 <1.0 <1.0 <1.0 52 24 39 37 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 33 35 35 33 1st Qtr 3/11/09 2nd Qtr 6/23/09 3rd Qtr 9/14/09 4th Qtr 12/29/09 <1.0 <1.0 <1.0 <1.0 81 120 280 250 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 35 37 37 41 1st Qtr 2/25/10 2nd Qtr 6/14/10 3rd Qtr 8/11/10 4th Qtr 10/15/10 <1.0 <1.0 <1.0 <1.0 1000 590 630 420 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 45 33 31 41 1st Qtr 2/23/11 2nd Qtr 5/26/11 3rd Qtr 8/17/11 4th Qtr 11/16/11 12/7/11<n (2)11/16/11 <1.0 <1.0 <1.0 NA <1.0 <1.0 NA 47 9.6 16 21 50 <1.0 <1.0 <1.0 NA <1.0 <1.0 <1.0 <1.0 <1.0 NA <1.0 <1.0 NA 40 42 39 36 33 1st Qtr 1/18/12 2nd Qtr 6/13/12 3rd Qtr 9/11/12 4th Qtr 10/3/12 <1.0 <1.0 <1.0 <1.0 38 4.7 6.9 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 38 40 41 1st Qtr 2/13/13 2nd Qtr 6/13/13 3rd Qtr 9/5/13 4th Qtr 11/13/13 <1.0 <1.0 <1.0 <1.0 6.89 4.86 5.93 5.51 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 40.4 37.9 40.6 40.2 1st Qtr 1/29/14 2nd Qtr 5/22/14 3rd Qtr 8/14/14 (3)3rd Qtr 9/24/14 4th Qtr 10/29/14 <1.0 <1.0 <1.0 <1.0 <1.0 5.7 10.3 202 260 723 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 40.6 37 40 NA 41.1 NA 1st Qtr 3/12/15 2nd Qtr 6/10/15 3rd Qtr 9/10/15 <1.0 <1.0 <1.0 1,180 1,040 1,040 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 (1) VOCs were resampled because laboratory missed holding (2) Results of the TW4-70 the duplicate sample for TW4-6. (3) Reanalyzed for VOCs only. NA = not analyzed Shaded indicates concentrations exceeding GWQS. time. 41.2 41.6 47 5.3 5.9 6.8 TABLE 1 (10 Of 27) Historic Summary Of Monitoring Parameters Up To The 3rd Quarter 2015 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Carbon Tetrachloride (5 pg/L) Chloroform (70 H9'l) Chloromethane ___(3Qjjfl/y___ Parameter (GWQS) Methylene Chloride (5 pg/L) Chloride No GWQS (mg/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 NA NA <10 <50 3,100 2,700 3,100 2,500 NA NA <10 <50 NA NA <10 <50 NA NA NA 52 5.2 5.4 5.2 5.3 1st Qtr 3/9/06 2nd Qtr 6/14/06 3rd Qtr 7/20/06 4th Qtr 11/8/06 <50 <50 <50 1.5 1,900 2,200 2,140 2,160 <50 <50 <50 <1.0 <50 <50 <50 <1.0 48 47 51 49 1 4.5 4.7 4.6 1st Qtr 2/28/07 2nd Qtr 6/27/07 3rd Qtr 8/15/07 4th Qtr 10/10/07 1.1 1.5 1.4 1.2 1,830 2,600 2,300 1,900 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 47 45 44 45 6 5.1 4.7 4.7 1st Qtr 3/28/08 2nd Qtr 6/25/08 3rd Qtr 9/10/08 4th Qtr 10/15/08 11/18/08 NA <2.0 1.3 1.3 1.4 NA 2,200 1,800 1,600 2,500 <1.0 <1.0 <1.0 NA <2.0 <1.0 <1.0 <1.0 NA <2.0 NA 43 43 35 40 NA 4.2 4.8 4.16 4.01 1st Qtr 3/11/09 2nd Qtr 6/23/09 3rd Qtr 9/14/09 4th Qtr 12/29/09 <1.0 <1.0 1.2 1 1,800 1,400 1,500 1,300 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 35 37 37 37 3.7 3.8 4.1 4.2 1st Qtr 3/3/10 2nd Qtr 6/14/10 3rd Qtr 8/11/10 4th Qtr 10/15/10 <1.0 <1.0 <1.0 1,200 1,100 1,500 1,100 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 35 31 36 38 3.8 3.9 3.9 4 3.6 4.0 4.1 3.8 3.9 4.0 3.8 3.8 3.5 4.0 4.2 4.1 ”4.2 4.2 2.9 3.7 "4.3 2.6 4.7 1st Qtr 2/23/11 2nd Qtr 6/1/11 3rd Qtr 8/18/11 4th Qtr 11/29/11 <1.0 <1.0 <1.0 <1.0 1,300 1,200 1,200 1,000 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 45 35 37 37 1st Qtr 1/19/12 2nd Qtr 6/14/12 3rd Qtr 9/13/12 4th Qtr 10/4/12 <1.0 <1.0 <1.0 <1.0 1,000 790 870 940 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 37 41 40 41 1st Qtr 2/13/13 2nd Qtr 6/18/13 3rd Qtr 9/12/13 4th Qtr 11/14/13 <1.0 <1.0 <1.0 <1.0 940 953 1,040 1.050 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 37.7 39.3 36.4 37.2 1st Qtr 2/5/14 2nd Qtr 5/22/14 3rd Qtr 8/27/14 4th Qtr 10/30/14 <1.0 <1.0 5.41 4.78 946 847 857 926 <1.0 <1.0 1.5 <1.0 <1.0 <1.0 <1.0 <1.0 38.2 37.7 39 40.2 1st Qtr 3/18/15 2nd Qtr 6/11/15 3rd Qtr 9/10/15 <1.0 <1.0 <1.0 942 950 897 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 40.4 42.1 46.7 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 2015 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Carbon Tetrachloride (Spg/L)______ Chloroform (70 ug/L) Chloromethane (30 pg/L) Parameter (GWQS) Methylene Chloride _____iiMM_____ Chloride No GWQS (mg/L) Nitrate, Nitrate + Nitrite (10 mgIL) TW4-8 1st Qtr 3/16/05 2nd Qtr 5/25/05 3rd Qtr 8/31/05 4th Qtr 12/7/05 NA NA <1.0 <1.0 <1.0 <1.0 10 1.1 NA NA <1.0 1.7 NA NA NA <1.0 NA NA NA 41 <0.1 <1.0 <1.0 0.2 1st Qtr 3/9/06 2nd Qtr 6/14/06 3rd Qtr 7/20/06 4th Qtr 11/8/06 <1.0 <1.0 <1.0 <1.0 1.3 1.8 2.1 1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 39 37 39 40 <1.0 <.1 0.3 0.1 1st Qtr 2/28/07 2nd Qtr 6/27/07 3rd Qtr 8/15/07 4th Qtr 10/10/07 <1.0 <1.0 <1.0 <1.0 2.5 2.5 1.5 3.5 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 39 42 42 43 <1.0 0.7 0.2 0.5 0.11st Qtr 3/28/08 2nd Qtr 6/25/08 3rd Qtr 9/10/08 4th Qtr 10/15/08 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 46 45 39 44 <1.0 <0.05 <0.05 1st Qtr 3/4/09 2nd Qtr 6/23/09 3rd Qtr 9/14/09 4th Qtr 12/17/09 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 42 44 44 51 <0.1 <0.1 <0.1 <0.1 1st Qtr 2/24/10 2nd Qtr 6/14/10 3rd Qtr 8/18/10 4th Qtr 10/15/10 <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 57 42 45 46 <0.1 <0.1 <0.1 0.1 1st Qtr 2/16/11 2nd Qtr 5/25/11 3rd Qtr 8/16/11 4th Qtr 11/16/11 (D12/7/11 <1.0 <1.0 <1.0 <1.0 <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 52 45 46 45 <0.1 NA 0.1 0.1 0.2 1st Qtr 1/18/12 2nd Qtr 5/13/12 3rd Qtr 8/29/12 4th Qtr 10/3/12 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 45 44 48 47 <0.1 0.3 0.2 0.1 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 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 46.6 45.5 47.5 46.1 <0.1 <0.1 0.4 0.1 1st Qtr 1/23/14 <2,2/6/2014 2nd Qtr 5/22/14 3rd Qtr 8/27/14 4th Qtr 10/29/14 <1.0 <1.0 <1.0 <1.0 <1.0 63.8 100.0 122.0 107 191 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 48.5 46.5 53 47 46.7 0.2 0.2 0.5 0.6 0.9 2.3 1.9 2.0 1st Qtr 3/12/15 2nd Qtr 6/11/15 3rd Qtr 9/10/15 <1.0 <1.0 <1.0 961 981 747 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 49.6 53 59.6 (1) VOCs were resampled because laboratory missed holding time. (2) Resampled to verily chloroform concentration that was collected on 1/23/14. NA = not analyzed Shaded indicates concentrations exceeding GWQS. TABLE 1 (12 of 27) Historic Summary Of Monitoring Parameters Up To The 3rd Quarter 2015 Chloroform Contamination Investigation OUSA White Mesa Mill Well Sampling Event Carbon Tetrachloride (5 pg/L) Chloroform (70 ug/L) Chloromethane ___(30 ng/L) Parameter (GWQS) Methylene Chloride ______(5 Mg/L)_____ Chloride No GWQS (mg/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 NA NA <1.0 <1.0 3.8 1.2 <1.0 <1.0 NA NA <1.0 2.9 NA NA <1.0 <1.0 NA NA NA 42 1.3 1.3 1.3 1.3 1st Qtr 3/9/06 2nd Qtr 6/14/06 3rd Qtr 7/20/06 4th Qtr 11/8/06 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 19 2.6 2.7 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 38 39 41 44 1.5 1.5 0.9 0.7 1st Qtr 2/28/07 2nd Qtr 6/27/07 3rd Qtr 8/15/07 4th Qtr 10/10/07 <1.0 <1.0 <1.0 <1.0 <1.0 21 9.5 8.7 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 44 42 38 40 0.6 1.3 1.8 2 1st Qtr 3/28/08 2nd Qtr 6/25/08 3rd Qtr 9/10/08 4th Qtr 10/15/08 <1.0 <1.0 <1.0 <1.0 1.3 1 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 35 35 28 58 2.1 2.3 2.79 1.99 1st Qtr 3/4/09 2nd Qtr 6/23/09 3rd Qtr 9/14/09 4th Qtr 12/17/09 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 30 30 30 37 2.5 2.3 2.5 1.7 1st Qtr 2/23/10 2nd Qtr 6/14/10 3rd Qtr 8/13/10 4 th Qtr 10/15/10 <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 47 33 40 34 1.4 1.5 1.2 1.8 1.3 3.4 4 2.3 1st Qtr 2/17/11 2nd Qtr 5/25/11 3rd Qtr 8/16/11 4th Qtr 11/16/11 (1) 12/7/11 <1.0 <1.0 <1.0 NA <1.0 <1.0 <1.0 <1.0 NA <1.0 <1.0 <1.0 <1.0 NA <1.0 <1.0 <1.0 <1.0 NA <1.0 NA 41 38 21 38 1st Qtr 1/18/12 2nd Qtr 5/31/12 3rd Qtr 8/30/12 4th Qtr 10/3/12 <1.0 <1.0 <1.0 <1.0 <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 23 22 21 2.3 4.0 3.9 3.8 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 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 20.6 21.4 22.7 23.6 4.5 4.5 4.0 4.9 4.4 3.4 2.7 4.3 3.3 1.8 1.4 1st Qtr 1/29/14 2nd Qtr 5/22/14 3rd Qtr 8/14/14 4th Qtr 10/29/14 <1.0 <1.0 <1.0 <1.0 <1.0 6.9 47 101 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 22 24 27 25 1st Qtr 3/12/15 2nd Qtr 6/11/15 3rd Qtr 9/3/15 <1.0 <1.0 <1.0 53.5 35.1 48 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 29.5 35.3 39.3 (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 2015 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Carbon Tetrachloride ______(5pg/L)______ Chloroform (70 ugfl-) Chloromethane (30 pg/L) Parameter (GWQS) Methylene Chloride (S ug/L) Chloride No GWQS (mg/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 NA NA <2.5 <2.5 140 62 110 300 NA NA 6.2 <2.5 NA NA <2.5 <2.5 NA NA NA 52 1.6 0.8 1.1 3.3 1st Qtr 3/9/06 2nd Qtr 6/14/06 3rd Qtr 7/20/06 4th Qtr 11/8/0§ <5.0 <5.0 <5.0 <1.0 190 300 504 452 <5.0 <5.0 <5.0 1.6 <5.0 <5.0 <5.0 <1.0 50 54 61 58 2.4 3.5 6.8 5.7 1st Qtr 2/28/07 2nd Qtr 6/27/07 3rd Qtr 8/15/07 4th Qtr 10/10/07 <1.0 <1.0 <1.0 <1.0 500 350 660 470 <1.0 <1.0 <1,0 <1.0 <1.0 <1.0 <1.0 <1.0 2 54 59 59 7.3 5.1 7.3 6.7 1st Qtr 3/28/08 2nd Qtr 6/25/08 3rd Qtr 9/10/08 4th Qtr 10/15/08 11/18/08 <1.0 <1.0 <1.0 NA <2.0 620 720 660 NA 1.200 <1.0 <1.0 <1.0 NA <2.0 <1.0 <1.0 <1.0 NA <2.0 NA 55 58 51 61 NA 7.3 9.9 9.23 10.5 1st Qtr 3/11/09 2nd Qtr 6/23/09 3rd Qtr 9/14/09 4th Qtr 12/22/09 <1.0 <1.0 <1.0 <1.0 1,100 1,200 910 300 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 64 62 51 51 11.6 9.8 8.1 3.8 1st Qtr 3/3/10 2nd Qtr 6/14/10 3rd Qtr 8/12/10 4th Qtr 10/15/10 <1.0 <1.0 <1.0 <1.0 460 220 100 1,100 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 48 42 38 52 11.0 5.0 1.6 0.8 1st Qtr 2/23/11 2nd Qtr 6/14/11 3rd Qtr 8/17/11 4th Qtr 11/16/11 <1.0 <1.0 <1.0 <1.0 620 280 180 110 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 32 42 41 45 9.0 3.3 1.9 1.1 1st Qtr 1/19/12 2nd Qtr 6/14/11 3rd Qtr 9/12/12 4th Qtr 10/3/12 <1.0 <1.0 <1.0 <1.0 76 79 130 140 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 40 46 44 45 0.9 0.8 1.0 1.6 1st Qtr 2/13/13 2nd Qtr 6/13/13 3rd Qtr 9/12/13 4th Qtr 11/14/13 <1.0 <1.0 <1.0 <1.0 154 486 1,126 1,380 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 49.1 51.5 67.9 70.9 1.2 5.6 13.0 16.0 1st Qtr 1/29/14 2nd Qtr 5/23/14 3rd Qtr 8/27/14 4 th Qtr 10/30/14 <1.0 <1.0 <1.0 5.16 1,260 1,110 1,060 1,220 <1.0 <1.0 <1.0 1.5 <1.0 <1.0 <1.0 <1.0 73 77.3 74 75.2 16.8 13.9 ...........13.| 1st Qtr 3/18/15 2nd Qtr 6/11/15 3rd Qtr 9/10/15 <1.0 <1.0 <1.0 1,210 1,240 1,280 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 78.6 75 89.5 jM 15.0 11.4 NA = not analyzed Shaded indicates concentrations exceeding GWQS. TABLE 1 (14 of 27) Historic Summary Of Monitoring Parameters Up To The 3rd Quarter 2015 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Carbon Tetrachloride My______ Chloroform (70 pg/L) Chloromethane ___(30 M9'y___ Parameter (GWQS) Methylene Chloride (S ug/L) Chloride No GWQS (mg/L) Nitrate, Nitrate + Nitrite _______(10 mg/L)_______ TW4-11 (chloroform pumping well) 1st Qtr 3/16/05 2nd Qtr 5/25/05 3rd Qtr 8/31/05 4th Qtr 12/7/05 NA NA <10 <100 4,400 3,590 4,400 4,400 NA NA <10 <100 NA NA <10 <100 NA NA NA 58 8.7 10.3 9.4 9.4 1st Qtr 3/9/06 2nd Qtr 6/14/06 3rd Qtr 7/20/06 4th Qtr 11/8/06 <50 <50 <50 1.7 4,400 4,300 4,080 3,660 <50 <50 <50 <50 <50 <50 2.7 1.3 56 56 55 55 9.2 10.0 10.0 10.0 1st Qtr 2/28/07 2nd Qtr 6/27/07 3rd Qtr 8/15/07 4th Qtr 10/10/07 1.3 1.6 1.7 1.6 3,600 3,800 4,500 4,400 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 1.6 1.2 54 53 53 53 10.1 10.6 10.2 9.8 1st Qtr 3/28/08 2nd Qtr 6/25/08 3rd Qtr 9/10/08 4th Qtr 10/15/08 11/18/08 <1.0 <1.0 <1.0 NA <2.0 NA 340 640 900 1,000 <1.0 <1.0 <1.0 NA <2.0 <1.0 <1.0 <1.0 NA <2.0 NA 63 46 42 47 NA 7.7 7.3 7.9 9.5 1st Qtr 3/11/09 2nd Qtr 6/23/09 3rd Qtr 9/14/09 4th Qtr 12/29/09 <1.0 <1.0 <1.0 <1.0 1,000 980 1,000 860 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 49 44 49 46 7.3 6.8 7.0 6.6 1st Qtr 3/3/10 2nd Qtr 6/14/10 3rd Qtr 8/12/10 4th Qtr 10/15/10 <1.0 <1.0 <1.0 <1.0 820 820 800 720 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 42 40 43 49 6.8 6.9 6.7 6.4 6.5 7.3 7.1 7.1 6.8 6.7 3.0 7.0 6.8 7.4 7.8 8.0 8.5 6.9 5.4 7.3 8.7 8.5 9.6 1st Qtr 2/23/11 2nd Qtr 6/1/11 3rd Qtr 8/17/11 4th Qtr 11/16/11 <1.0 <1.0 <1.0 <1.0 1,000 930 820 1500 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 46 49 48 46 1st Qtr 1/24/12 2nd Qtr 6/13/12 3rd Qtr 9/13/12 4th Qtr 10/3/12 <1.0 <1.0 <1.0 <1.0 1st Qtr 2/13/13 2nd Qtr 6/18/13 3rd Qtr 9/12/13 4th Qtr 11/13/13 <1.0 <1.0 <1.0 610 660 740 730 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 3.23 867 788 865 874 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 43 52 49 50 47.3 49.3 46.6 46.7 1st Qtr 2/5/14 2nd Qtr 5/23/14 3rd Qtr 8/27/14 4th Qtr 10/29/14 <1.0 <1.0 <1.0 5.19 785 751 719 803 <1.0 <1.0 <1.0 1.2 <1.0 <1.0 <1.0 <1.0 48.5 51.6 48 56.4 1st Qtr 3/9/15 2nd Qtr 6/11/15 3rd Qtr 8/31/15 <1.0 <1.0 1.24 2,450 2,710 1,120 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 49.8 62.2 73.1 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 2015 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Carbon Tetrachloride M Chloroform (70 pgfL) Chloromethane (30 pg/L) Parameter (GWQS) Methylene Chloride (5 pg/L) Chloride No GWQS (mg/L) Nitrate, Nitrate + Nitrite no ™g'i) TW4-12 1st Qtr 3/16/05 2nd Qtr 5/25/05 3rd Qtr 8/31/05 4th Qtr 12/7/05 NA NA <1.0 <1.0 1st Qtr 3/9/06 2nd Qtr 6/14/06 3rd Qtr 7/20/06 4th Qtr 11/8/06 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 NA NA 5.8 1.0 NA NA <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 2.6 1.4 1.4 <1.0 <1.0 <1.0 <1.0 <1.0 NA NA NA 19 19 16 16 16 1.4 1.6 1.5 1.4 1.3 1.4 1.4 1.4 1st Qtr 2/28/07 2nd Qtr 6/27/07 3rd Qtr 8/15/07 4th Qtr 10/10/07 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 16 18 29 16 1.5 1.5 1.4 1.4 1st Qtr 3/28/08 2nd Qtr 6/25/08 3rd Qtr 9/10/08 4th Qtr 10/15/08 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 16 19 18 22 1.1 2.7 2.7 2.5 1st Qtr 3/11/09 2nd Qtr 6/23/09 3rd Qtr 9/14/09 4th Qtr 12/16/09 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 23 22 22 23 2.4 3.8 5.1 3.6 1st Qtr 2/23/10 2nd Qtr 6/14/10 3rd Qtr 8/10/10 4th Qtr 10/15/10 <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 22 29 35 31 4.0 11.0 9.0 8.0 1st Qtr 2/15/11 2nd Qtr 5/25/11 3rd Qtr 8/16/11 4th Qtr 11/15/11 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 31 32 31 30 6.5 7.0 6.8 8.0 1st Qtr 1/17/12 2nd Qtr 5/31/12 3rd Qtr 8/29/12 4th Qtr 10/3/12 <1.0 <1.0 <1.0 <1.0 <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 34 39 39 7.7 10.0 13.01 13.0 1st Qtr 2/13/13 2nd Qtr 5/29/13 3rd Qtr 8/29/13 4th Qtr 11/6/13 <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 36.7 38.6 41.7 41.4 12.6 14.2 17.4] 16.4 1st Qtr 1/22/14 2nd Qtr 5/21/14 3rd Qtr 8/27/14 4th Qtr 10/23/14 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 41.6 40.2 47 50.2 18.4 17.0 13.0 16.1 1st Qtr 3/11/15 2nd Qtr 6/10/15 3rd Qtr 9/2/15 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 50.6 56 60.2 19.2 18.816.4| NA = not analyzed Shaded indicates concentrations exceeding GWQS. TABLE 1 (16 of 27) Historic Summary Of Monitoring Parameters Up To The 3rd Quarter 2015 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Carbon Tetrachloride (5 ng/L) Chloroform (70 pg/L) Chloromethane ___(30 pg/L)___ Parameter (GWQS) Methylene Chloride (5 pg/L) Chloride No GWQS (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 NA NA <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 NA NA <1.0 3.1 NA NA <1.0 <1.0 NA NA NA 69 4.2 4.3 4.6 4.3 1st Qtr 3/9/06 2nd Qtr 6/14/06 3rd Qtr 7/20/06 4th Qtr 11/8/06 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 1.7 1.4 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 67 66 65 33 4.2 4.9 4.3 0.8 4.0 4.6 4.4 4.1 3.8 4.2 4.3 4.6 3.7 1.2 4.7 4.1 4.3 5.2 5.6 5.8 5.5 6.4 5.2 5.9 5.5 6.0 6.2 5.9 6.3 6.8 7.2 6.5 7.1 6.0 4.8 6.3 7.1 6.3 5.7 1st Qtr 2/28/07 2nd Qtr 6/27/07 3rd Qtr 8/15/07 4th Qtr 10/10/07 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 59 59 58 58 1st Qtr 3/28/08 2nd Qtr 6/25/08 3rd Qtr 9/10/08 4th Qtr 10/15/08 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 54 58 50 58 1st Qtr 3/4/09 2nd Qtr 6/23/09 3rd Qtr 9/14/09 4th Qtr 12/16/09 <1.0 <1.0 <1.0 <1.0 <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 57 63 60 1st Qtr 2/24/10 2nd Qtr 6/14/10 3rd Qtr 8/10/10 4th Qtr 10/15/10 <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 53 53 55 55 1st Qtr 2/15/11 2nd Qtr 5/25/11 3rd Qtr 8/16/11 4th Qtr 11/15/11 <1.0 <1.0 <1.0 <1.0 <1.0 <L0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 60 56 60 54 1st Qtr 1/17/12 2nd Qtr 5/31/12 3rd Qtr 8/29/12 4 th Qtr 10/3/12 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 55 59 60 60 1st Qtr 2/13/13 2nd Qtr 5/29/13 3rd Qtr 8/29/13 4th Qtr 11/6/13 <1.0 <1.0 <1.0 <1.0 1st Qtr 1/22/14 2nd Qtr 5/21/14 3rd Qtr 8/13/14 4th Qtr 10/23/14 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 59.3 56 63.5 58.5 63.1 56.1 62 66.1 1st Qtr 3/11/15 2nd Qtr 6/10/15 3rd Qtr 9/2/15 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 66.4 70.3 76.5 NA = not analyzed Shaded indicates concentrations exceeding GWQS. TABLE 1 (17 of 27) Historic Summary Of Monitoring Parameters Up To The 3rd Quarter 2015 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Carbon Tetrachloride ______(SM9/L)______ Chloroform (70 ug/L) Chloromethane (30 pg/L) Parameter (GWQS) Methylene Chloride (5 pg/L) Chloride No GWQS (mg/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 NS NS NS NS 1st Qtr 3/9/06 2nd Qtr 6/14/06 3rd Qtr 7/20/06 4th Qtr 11/8/06 NS NS NS <1.0 1st Qtr 2/28/07 2nd Qtr 6/27/07 3rd Qtr 8/15/07 4th Qtr 10/10/07 <1.0 <1.0 <1.0 <1.0 NS NS NS NS NS NS NS NS NS NS NS NS NS NS NS NS NS NS NS <1.0 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 NS NS NS NS NS NS NS NS NS NS NS NS NS NS 37 38 38 36 38 2.4 2.3 1.4 1.1 0.8 6.4 1.6 1.38 0.76 1st Qtr 3/28/08 2nd Qtr 6/25/08 3rd Qtr 9/10/08 4th Qtr 10/15/08 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 57 35 34 40 1st Qtr 3/4/09 2nd Qtr 6/23/09 3rd Qtr 9/14/09 4th Qtr 12/16/09 <1.0 <1.0 <1.0 <1.0 <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 36 38 34 1.6 1.4 1.5 1.4 1st Qtr 3/3/10 2nd Qtr 6/14/10 3rd Qtr 8/10/10 4th Qtr 10/15/10 <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 33 49 35 29 2.5 2.9 2.8 2.9 1.8 1.4 2.6 1.7 1.9 3.3 3.9 3.9 46 4.4 4.5 4.8 5.9 4.9 4.1 5.2 5.2 3.6 2.8 1st Qtr 2/15/11 2nd Qtr 6/14/11 3rd Qtr 8/16/11 4th Qtr 11/15/11 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 25 24 33 15 1st Qtr 1/17/12 2nd Qtr 6/14/11 3rd Qtr 8/29/12 4th Qtr 10/3/12 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 20 35 37 37 1st Qtr 2/7/13 2nd Qtr 5/29/13 3rd Qtr 8/29/13 4th Qtr 11/6/13 <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 35.2 38.6 37.6 36.5 1st Qtr 1/22/14 2nd Qtr 5/21/14 3rd Qtr 8/13/14 4th Qtr 10/23/14 <1.0 <1.0 <1.0 <1.0 1st Qtr 3/12/15 2nd Qtr 6/10/15 3rd Qtr 9/3/15 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 1.7 1.82 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 35.5 32.5 38 38.9 40.1 41.8 42.4 NS = not sampled Shaded indicates concentrations exceeding GWQS. TABLE 1 (18 of 27) Historic Summary Of Monitoring Parameters Up To The 3rd Quarter 2015 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Carbon Tetrachloride ______(5 pg/L)______ Chloroform (70 ug/L) Chloromethane (30 pg/L) Parameter (GWQS) Methylene Chloride (S ug/L) Chloride No GWQS (mg/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 NA NA <1.0 <1.0 240 212 85 14 NA NA NA NA 3.2 2.6 43 5.9 NA NA NA <0.1 <0.1 <0.1 64 1.4 1st Qtr 3/9/06 2nd Qtr 6/14/06 3rd Qtr 7/20/06 4th Qtr 11/8/06 <1.0 <1.0 <1.0 <1.0 39 13 5.2 13.6 1.1 2.4 <1.0 <1.0 21 8.9 2.7 9.2 60 55 60 62 3 1.9 2.7 5.6 1st Qtr 2/28/07 2nd Qtr 6/27/07 3rd Qtr 8/15/07 4th Qtr 10/10/07 <1.0 <1.0 <1.0 <1.0 8.7 2.6 7.1 1.4 <1.0 <1.0 <1.0 <1.0 6.6 1.8 5.1 1 79 75 65 69 12.3 9.9 5.4 4.4 <6.1 1.5 10.5 9.8 1st Qtr 3/28/08 2nd Qtr 6/25/08 3rd Qtr 9/10/08 4th Qtr 10/15/08 <1.0 <1.0 <1.0 <1.0 <1.0 11 10 3.9 <1.0 <1.0 <1.0 <1.0 <1.0 26 14 6.6 52 58 71 89 1st Qtr 3/4/09 2nd Qtr 6/23/09 3rd Qtr 9/14/09 4th Qtr 12/17/09 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 73 76 79 76 9.6 8.9 8.8 5.2 1st Qtr 2/24/10 2nd Qtr 6/14/10 3rd Qtr 8/24/10 4th Qtr 10/15/10 <1.0 <1.0 <1.0 <1.0 <1.0 2.1 4.3 3 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 77 64 72 71 4.2 4.7 4.6 3.3 7 5 1.7 0.4 1st Qtr 2/22/11 2nd Qtr 5/26/11 3rd Qtr 8/17/11 4th Qtr 11/16/11 (1> 12/7/11 <1.0 <1.0 <1.0 NA <1.0 15 16 9.2 NA <1.0 <1.0 <1.0 <1.0 NA <1.0 <1.0 <1.0 <1.0 NA 1.4 NA 86 81 63 38 1st Qtr 1/18/12 2nd Qtr 5/26/11 3rd Qtr 8/30/12 4th Qtr 10/3/12 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 1.7 <1.0 <1.0 <1.0 48 53 59 59 <0.1 <0.1 <0.1 0.1 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 <1.0 13.4 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 4.21 58.1 49.8 54.4 56.6 <0.1 <0.1 <0.1 1.4 1st Qtr 1/29/14 2nd Qtr 5/22/14 3rd Qtr 8/14/14 <2)3rd Qtr 9/24/14 4th Qtr 10/29/14 <1.0 <1.0 <1.0 <1.0 <1.0 6.93 14.6 229 371 387 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 66.8 80.7 80 NA 92.1 3.2 4.9 5.1 NA 8.4 1st Qtr 3/12/15 2nd Qtr 6/11/15 3rd Qtr 9/3/15 <1.0 <1.0 <1.0 153 65.3 82 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 65 61 65.8 4.3 1.06 1.2 (1) VOCs were resampled because laboratory missed holding (2) VOCs were resampled NA = not analyzed Shaded indicates concentrations exceeding GWQS. time. TABLE 1 (19 of 27) Historic Summary Of Monitoring Parameters Up To The 3rd Quarter 2015 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Carbon Tetrachloride (5 pg/L) Chloroform (70 ng/L) Chloromethane (30 pg/L) Parameter (GWQS) Methylene Chloride (5 pg/L) Chloride No GWQS (mg/L) Nitrate, Nitrate + Nitrite (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 NA NA <1.0 <1.0 1st Qtr 3/9/06 2nd Qtr 6/14/06 3rd Qtr 7/20/06 4th Qtr 11/8/06 <1.0 <1.0 <1.0 <1.0 1st Qtr 2/28/07 2nd Qtr 6/27/07 3rd Qtr 8/15/07 4th Qtr 10/10/07 <1.0 <1.0 <1.0 <1.0 38 29.8 39 14 NA NA 2.8 1.1 NA NA <1.0 <1.0 12 12 10.8 12.5 1.6 2.7 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 9.2 8 8.9 7.4 <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 14.1 12.9 13.3 7.3 5.9 4.7 6.1 5.7 5.1 4.9 5.0 4.4 1st Qtr 3/28/08 2nd Qtr 6/25/08 3rd Qtr 9/10/08 4th Qtr 10/15/08 <1.0 <1.0 <1.0 <1.0 6.4 5.7 8 9.4 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 23 23 26 30 0.7 4.6 4.9 5.2 1st Qtr 3/4/09 2nd Qtr 6/23/09 3rd Qtr 9/14/09 4th Qtr 12/22/09 <1.0 <1.0 <1.0 <1.0 11 16 13 8.2 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 29 30 26 30 5.2 6.2 5.9 5.4 1st Qtr 2/24/10 2nd Qtr 6/14/10 3rd Qtr 8/12/10 4th Qtr 10/15/10 <1.0 <1.0 <1.0 <1.0 69 29 29 30 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 41 35 37 50 5.1 9.0 9.0 10.0 1st Qtr 2/22/11 2nd Qtr 5/26/11 3rd Qtr 8/17/11 4th Qtr 11/16/11 (1) 12/7/11 <1.0 <1.0 <1.0 NA <1.0 NA 39 26 29 28 <1.0 <1.0 <1.0 NA <1.0 <1.0 <1.0 <1.0 NA <1.0 52 36 23 23 NA NA 10.0 9.0 4.6 6.3 1st Qtr 1/18/12 2nd Qtr 6/13/12 3rd Qtr 9/11/12 4th Qtr 10/3/12 <1.0 <1.0 <1.0 <1.0 25 24 38 30 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 18 30 26 27 4.4 6.6 6.6 6.0 1st Qtr 2/13/13 2nd Qtr 6/13/13 3rd Qtr 9/5/13 4th Qtr 11/13/13 <1.0 <1.0 <1.0 <1.0 34.9 37.9 41 44.3 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 23.1 22.9 36.2 37.1 5.6 8.9 12.1 14.2 1st Qtr 1/30/14 2nd Qtr 5/22/14 3rd Qtr 8/14/14 4th Qtr 10/28/14 <1.0 <1.0 <1.0 <1.0 6.93 6.93 32.8 33 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 38.9 47 49 40.8 12.8 12.2 9.8 11.1 1st Qtr 3/12/15 2nd Qtr 6/11/15 3rd Qtr 9/3/15 <1.0 <1.0 <1.0 32 30.5 28.7 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 41.6 43.5 47.6 11.7 9.69 15.7 (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 2015 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Carbon Tetrachloride ______(5 M9'L)______ Chloroform (70 pg/L) Chloro methane ___(3P,My___ Parameter (GWQS) Methylene Chloride (Spg/L) Chloride No GWQS (mg/L) Nitrate, Nitrate + Nitrite ______(10 mg/L)______ TW4-19 chlorofrom pumping well 1st Qtr 3/16/05 2nd Qtr 5/25/05 3rd Qtr 8/31/05 4th Qtr 12/7/05 NA NA <5.0 <50 2,200 1,200 1,400 .1,800 NA NA <5.0 <50 NA NA <5.0 <50 NA NA NA 81 <0.1 5.3 5.7 4.6 1st Qtr 3/9/06 2nd Qtr 6/14/06 3rd Qtr 7/20/06 4th Qtr 11/8/06 <50 <50 <50 1,200 1.6 1,100 1,120 .i,Q5P <50 <50 <50 2.6 <50 <50 <50 <1.0 86 116 123 134 4 5.2 4.3 4.6 1st Qtr 2/28/07 2nd Qtr 6/27/07 3rd Qtr 8/15/07 4th Qtr 10/10/07 1.3 1.9 1.9 1,200 <1.0 1,100 1,100 <1.0 <1,0 <1.0 Did not sample <1.0 <1.0 133 129 132 4.1 4 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 <1.0 2,9 8.6 12 ................ 1.2 1.2 15 16 1,800 1,000 3,600 4,200 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 1,100 990 6,600 4,700 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 131 128 113 124 127 132 43 124 2.2 2.8 35.2 47.8 3.2 2.4 <0.1 26,7 1st Qtr 2/17/10 2nd Qtr 6/14/10 3rd Qtr 8/16/10 4th Qtr 10/15/10 1.3 4.2 4.9 1.3 940 1,800 2,000 1,200 <1.0 <1.0 <1.0 <10 <1.0 <1.0 <1.0 <1.0 144 132 142 146 2 4.4 5.9 2.7 1st Qtr 2/17/11 2nd Qtr 6/7/11 3rd Qtr 8/17/11 4th Qtr 11/17/11 <1) 12/5/11 17 8.3 2.1 5.4 3,400 4,000 970 <1.0 <1.0 <1.0 ...2,200.<1.0 <1.0 <1.0 <1.0 <1.0 135 148 148 148 17.0 12.0 3.0 5.0 1st Qtr 1/23/12 2nd Qtr 6/6/12 3rd Qtr 9/4/12 4th Qtr 10/3/12 1.5 1.1 3.5 4 650 460 950 1500 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 138 149 149 150 0.6 2.4 2.5 4.1 1st Qtr 2/13/13 2nd Qtr 6/5/13 3rd Qtr 9/3/13 4th Qtr 10/29/13 1st Qtr 1/27/14 2nd Qtr 5/19/14 3rd Qtr 8/11/14 4th Qtr 10/21/14 5.15 5.15 20.7 6.42 4,210 2,070 8,100 942 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 4.05 5.51 1.9 4.8 586 810 1,410 4,310 <1.0 <1.0 8,3 <1.0 <1.0 <1.0 <1,0 <1.0 164 148 179 134 134 152 140 130 8.0 3.0 17.6 4.7 1.6 1.3 1.6 4.7 1st Qtr 3/9/15 2nd Qtr 6/8/15 3rd Qtr 8/31/15 8.92 2.62 4,660 1,570 <1.0 <1.0 <1.0 7.78 <1.0 <1.0 <1.0 238 180 326 8.56 0.916 11.6 (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 2015 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Carbon Tetrachloride (S pg/L) Chloroform (70 Ufl/L) Chloromethane (30 pg/L) Parameter (GWQS) Methylene Chloride (5 pg/L) Chloride No GWQS (mg/L) Nitrate, Nitrate + Nitrite _______(10 mg/L)______ TW4-20 chloroform pumping well 1st Qtr 3/16/05 2nd Qtr 5/25/05 3rd Qtr 8/31/05 4th Qtr 12/7/05 NA <10 <250 39.000 3,800 19.000 Monitor well was not installed NA NA <10 <10 <250 <250 NA NA 131 10.10 2.90 1.80 1st Qtr 3/9/06 2nd Qtr 6/14/06 3rd Qtr 7/20/06 4th Qtr 11/8/06 <500 <500 <1000 7.1 9,200 61,000 5,300 11,000 <500 <500 <1000 <500 <500 <1000 1.9 2.2 120 235 134 124 3.80 9.40 2.90 3.50 1st Qtr 2/28/07 2nd Qtr 6/27/07 3rd Qtr 8/15/07 4th Qtr 10/10/07 3.1 2.2 3.5 6.8 4,400 1,800 5,200 9,000 <1.0 <1.0 <1.0 <1.0 <1.0 1.1 1.8 1.9 124 112 117 170 4.20 2.30 2.10 5.60 1st Qtr 3/28/08 2nd Qtr 6/25/08 3rd Qtr 9/10/08 4th Qtr 10/15/08 NA 13.000 30.000 21.000 NA <1.0 <1.0 <1.0 NA 1.5 1.2 3.7 NA 132 191 156 168 0.90 8.00 4.44 5.51 1st Qtr 3/4/09 2nd Qtr 6/23/09 3rd Qtr 9/14/09 4th Qtr 12/14/09 5.7 4.9 8.4 14 8,200 6,800 13.000 15.000 <1.0 <1.0 <1.0 <1.0 5.2 4.2 4.4 3.0 164 164 153 187 5.10 2.90 3.30 5.30 1st Qtr 2/17/10 2nd Qtr 6/14/10 3rd Qtr 8/16/10 4th Qtr 10/15/10 2.7 11 12 20 3,500 18,000 15.000 24.000 <1.0 <1.0 <1.0 <1.0 3.2 3.7 2.2 5.5 179 200 196 203 2.00 5.60 5.30 4.60 1st Qtr 2/23/11 2nd Qtr 6/1/10 3rd Qtr 8/17/11 4th Qtr 11/16/11 27 10 7.3 7.2 31,000 8,100 3,800 7,900 <1.0 <1.0 <1.0 <1.0 19.0 2.1 3.1 2.5 220 177 207 186 4.40 4.80 6.50 4.20 1st Qtr 1/23/12 2nd Qtr 6/6/12 3rd Qtr 9/4/12 4th Qtr 10/3/12 10 33 26 22 11000 36.000 13.000 19.000 <1.0 <1.0 <1.0 <1.0 1.3 <1.0 <1.0 <1.0 207 262 289 302 7.90 11.00 10.80 11.00 1st Qtr 2/11/13 2nd Qtr 6/5/13 3rd Qtr 9/3/13 4th Qtr 10/29/13 19.6 32.5 25.7 17.3 18,500 26,300 26,800 15,700 <1.0 <1.0 <1.0 <1.0 1.21 1.3 2.14 1.37 252 250 260 272 9.07 9.80 8.65 9.64 1st Qtr 1/27/14 2nd Qtr 5/19/14 3rd Qtr 8/11/14 4th Qtr 10/21/14 18.4 22.1 14.1 18.5 17,800 22,100 12,400 23,300 <1.0 2.31 55.2 4.04 2.04 3.98 2.2 2.38 254 269 299 292 7.56 5.95 4.30 7.67 1st Qtr 3/9/15 2nd Qtr 6/8/15 3rd Qtr 8/31/15 20.8 16.2 15.1 19,900 17,600 17,000 4.85 13.4 12.3 1.38 1.73 <1.0 290 296 365 9.80 5.76 9.3 (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 2015 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Carbon Tetrachloride (5Mg/L)______ Chloroform (70 pg/L) Chloromethane ___(30 ng/L)___ Parameter (GWQS) Methylene Chloride ______(s ug/L)______ Chloride No GWQS (mg/L) Nitrate, Nitrate + Nitrite (10 mg/L) TW4-21 (chloroform pumping well) 1st Qtr 3/16/05 2nd Qtr 5/25/05 NA 3rd Qtr 8/31/05 <5.0 4th Qtr 12/7/05 <1.0 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 <2.5 <2.5 <2.5 <1.0 <1.0 1.8 5.8 192 78 86 120 120 108 139 160 300 140 120 Monitor well was not installed NA NA <5.0 <5.0 <1.0 <1.0 <2.5 <2.5 <2.5 <1.0 <1.0 <1.0 <1.0 <1.0 <2.5 <2.5 <2.5 <1.0 <1.0 <1.0 <1.0 <1.0 NA NA 353 347 318 357 296 306 327 300 288 14.6 10.1 9.6 8.5 10.2 8.9 8.7 8.7 8.6 8.6 8.3 1st Qtr 3/28/08 2nd Qtr 6/25/08 3rd Qtr 9/10/08 4th Qtr 10/15/08 11/18/08 NA 7 1.7 1.6 NA 390 180 120 170 <1.0 <1.0 <1.0 NA <2.0 <1.0 <1.0 <1.0 NA <2.0 NA 331 271 244 284 NA 14.3 8.8 7.57 8.0 1st Qtr 3/11/09 2nd Qtr 6/23/09 3rd Qtr 9/14/09 4th Qtr 12/22/09 <1.0 <1.0 <1.0 <1.0 1st Qtr 2/25/10 2nd Qtr 614/10 3rd Qtr 8/13/10 4th Qtr 10/15/10 <1.0 <1.0 1st Qtr 2/22/11 2nd Qtr 6/28/11 3rd Qtr 8/17/11 4th Qtr 11/16/11 (1> 12/7/11 180 200 200 160 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 9.2 1.2 170 210 390 200 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 1.2 4.8 6.3 6.7 230 290 460 390 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 279 291 281 256 228 266 278 210 303 290 287 287 8.3 8.1 9.2 8.4 8.4 12.0 14.0 7.0 9.0 12.0 14.0 13.0 1st Qtr 1/19/12 2nd Qtr 6/13/12 3rd Qtr 9/13/12 4th Qtr 10/4/12 6.4 5.4 6 7 420 400 410 390 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 228 285 142 270 15.0 11.0 13.0 14.0 1st Qtr 2/13/13 2nd Qtr 6/18/13 3rd Qtr 9/13/13 4th Qtr 11/13/13 <1.0 5.25 3.49 2.13 282 328 244 204 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 221 243 207 206 11.8 13.8 10.3 9.0 1st Qtr 2/5/14 2nd Qtr 5/22/14 3rd Qtr 8/27/14 4th Qtr 10/29/14 <1.0 1.04 6.23 4.73 220 240 204 229 <1.0 <1.0 <1.0 <1.0 2.04 2.04 <1.0 <1.0 200 243 230 252 11.4 11.5 7.1 10.0 1st Qtr 3/12/15 2nd Qtr 6/8/15 3rd Qtr 8/31/15 1.75 1.92 <1.0 292 366 281 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 255 494 499 10.9 13.1 14.7 (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 2015 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Carbon Tetrachloride (5 pg/L) Chloroform (70 pg/L) Chloromethane (30 ug/L) Parameter (GWQS) Methylene Chloride (5 pg/L) Chloride No GWQS (mg/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 NA <5.0 <5.0 340 290 320 Monitor well was not installed NA NA <5.0 <5.0 <5.0 <5.0 NA NA 253 18.2 15.7 15.1 1st Qtr 3/9/06 2nd Qtr 6/14/06 3rd Qtr 7/20/06 4th Qtr 11/8/06 <10 <10 <10 <1.0 390 280 864 350 <10 <10 <10 1.6 <10 <10 <10 <1.0 236 221 221 236 15.3 14.3 14.5 15.9 1st Qtr 2/28/07 2nd Qtr 6/27/07 3rd Qtr 8/15/07 4th Qtr 10/10/07 <1.0 <1.0 <1.0 <1.0 440 740 530 440 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 347 273 259 238 20.9 19.3 19.3 18.8 1st Qtr 3/28/08 2nd Qtr 6/25/08 3rd Qtr 9/10/08 4th Qtr 10/15/08 11/18/08 <1.0 <1.0 NA <2.0 1.3 NA 1,400 1,200 6,300 630 <1.0 <1.0 <1.0 NA <2.0 <1.0 <1.0 <1.0 NA <2.0 NA 519 271 524 539 NA 39.1 41.9 38.7 36.3 1st Qtr 3/11/09 2nd Qtr 6/23/09 3rd Qtr 9/14/09 4th Qtr 12/29/09 <1.0 <1.0 <1.0 <1.0 390 730 2,300 380 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 177 177 391 175 20.7 20.6 40.3 17.8 1st Qtr 3/3/10 2nd Qtr 6/14/10 3rd Qtr 8/24/10 4th Qtr 10/15/10 <1.0 <1.0 <1.0 <1.0 2,200 540 340 340 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 427 134 130 134 36.8 19.0 15.0 16.0 1st Qtr 2/22/11 2nd Qtr 6/1/11 3rd Qtr 8/17/11 4th Qtr 11/16/11 (1) 12/7/11 <1.0 <1.0 NA <1.0 1.2 NA 1,300 210 450 400 <1.0 <1.0 <1.0 NA <1.0 <1.0 <1.0 <1.0 NA <1.0 114 138 120 174 NA NA 18.0 17.0 15.0 19.0 1st Qtr 1/19/12 2nd Qtr 6/13/12 3rd Qtr 9/12/12 4th Qtr 10/4/12 <1.0 <1.0 <1.0 <1.0 200 120 121 330 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 36 35 130 14.0 12.8 7.0 14.0 1st Qtr 2/11/13 2nd Qtr 6/5/13 3rd Qtr 9/3/13 4th Qtr 10/29/13 3.24 3.35 3.25 8.09 10,600 12,500 9,640 13,300 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 130 586 487 501 58.0 50.2 29.7 45.2 1st Qtr 1/27/14 2nd Qtr 5/19/14 3rd Qtr 8/11/14 4th Qtr 10/29/14 6.06 6.65 1.9 3.32 12,100 12,400 12,400 12,400 <1.0 <1.0 2.83 40 1.61 <1.0 <1.0 <1.0 598 614 540 596 54.6 47.2 41.5 54.9 1st Qtr 3/9/15 2nd Qtr 6/8/15 3rd Qtr 8/31/15 <1.0 3.77 2.42 12,700 8,050 7,810 4.31 3.42 5.47 <1.0 <1.0 <1.0 675 390 557 69.2 47.1 64.7 (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 2015 Chloroform Contamination Investigation DUSA White Mesa Mill Weii Sampling Event Carbon Tetrachloride (5 ug/L) Chloroform (7Q van.) Chloromethane ___(30 pg/L)___ Parameter (GWQS) Methylene Chloride _____ (5pg/L)_____ Chloride No GWQS (mg/L) Nitrate, Nitrate + Nitrite (10 mg/L) TW4-23 2nd Qtr 6/27/07 3rd Qtr 8/15/07 4th Qtr 10/10/07 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 47 46 43 <0.1 <0.1 <0.1 1st Qtr 3/28/08 2nd Qtr 6/25/08 3rd Qtr 9/10/08 4th Qtr 10/15/08 11/18/08 <1.0 <1.0 <1.0 NA <2.0 <1.0 <1.0 <1.0 NA <2.0 <1.0 <1.0 <1.0 NA <2.0 <1.0 <1.0 <1.0 NA <2.0 NA 41 41 35 51 <0.1 <0.1 <0.05 <0.05 NA 1st Qtr 3/4/09 2nd Qtr 6/23/09 3rd Qtr 9/14/09 4th Qtr 12/16/09 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 41 43 43 37 <0.1 <0.1 <0.1 <0.1 1st Qtr 2/24/10 2nd Qtr 6/14/10 3rd Qtr 8/24/10 4th Qtr 10/15/10 <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 45 40 40 34 <0.1 <0.1 <0.1 <0.1 1st Qtr 2/16/11 2nd Qtr 6/14/11 3rd Qtr 8/16/11 4th Qtr 11/15/11 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 44 44 41 43 <0.1 <0.1 <0.1 <0.1 1st Qtr 1/17/12 2nd Qtr 5/31/12 3rd Qtr 8/29/12 4th Qtr 10/3/12 <1.0 <1.0 <1.0 <1.0 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 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 40 44 46 45 <0.1 <0.1 <0.1 <0.1 43.6 44.7 48 43 <0.1 0.1 <0.1 <0.1 1st Qtr 1/23/14 2nd Qtr 5/19/14 3rd Qtr 8/13/14 4th Qtr 10/28/14 <1.0 <1.0 <1.0 <1.0 <1.0 <i.O <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 44.6 42.3 46 46.8 <0.1 <0.1 <0.1 <0.1 1st Qtr 3/12/15 2nd Qtr 6/8/15 3rd Qtr 9/3/15 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 47.3 48.4 54.1 <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 3rd Quarter 2015 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Carbon Tetrachloride (5 M9/L) Chloroform (70 pg/L) Chloromethane (30 pg/L) Parameter (GWQS) Methylene Chloride (5 pg/L) Chloride No GWQS (mg/L) Nitrate, Nitrate + Nitrite (10 mg/L) TW4-24 nitrate pumping well 2nd Qtr 6/27/07 3rd Qtr 8/15/07 4th Qtr 10/10/07 <1.0 <1.0 <1.0 2.6 2.2 1.5 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 770 791 692 26.1 29 24.7 1st Qtr 3/28/08 2nd Qtr 6/25/08 3rd Qtr 9/10/08 4th Qtr 10/15/08 11/18/08 <1.0 <1.0 <1.0 NA <2.0 1.5 1.4 2.9 NA <2.0 <1.0 <1.0 <1.0 NA <2.0 <1.0 <1.0 <1.0 NA <2.0 NA 740 834 1180 1130 NA 24.4 45.3 38.4 44.8 1st Qtr 3/4/09 2nd Qtr 6/23/09 3rd Qtr 9/14/09 4th Qtr 12/16/09 <1.0 <1.0 <1.0 <1.0 1.4 1.5 1.4 1.2 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 1010 759 618 1080 30.5 30.4 30.7 28.3 1st Qtr 2/25/10 2nd Qtr 6/14/10 3rd Qtr 8/24/10 4th Qtr 10/15/10 <1.0 <1.0 <1.0 <1.0 1.3 1.7 1.8 1.4 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 896 639 587 522 33.1 30 31 31 1st Qtr 2/17/11 2nd Qtr 5/26/11 3rd Qtr 8/17/11 4th Qtr 11/16/11 <1> 12/7/11 <1.0 <1.0 <1.0 NA <1.0 NA 1.8 1.1 1.7 1.2 <1.0 <1.0 <1.0 NA <1.0 <1.0 <1.0 <1.0 NA <1.0 NA 1100 1110 967 608 NA 31 35 34 35 1st Qtr 1/16/12 2nd Qtr 6/6/12 3rd Qtr 8/30/12 4th Qtr 10/3/12 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 373 355 489 405 37 37 37 38 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 17.4 21.8 32.5 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 1260 916 998 1030 35.9 23.7 33 35 1st Qtr 1/27/14 2nd Qtr 5/19/14 3rd Qtr 8/11/14 4th Qtr 10/21/14 1.18 <1.0 <1.0 <1.0 78.5 62.7 76.3 25.8 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 809 1020 1150 1050 31.6 35.0 31.5 35.7 1st Qtr 3/9/15 2nd Qtr 6/8/15 3rd Qtr 8/31/15 <1.0 <1.0 <1.0 49.2 4.28 46.9 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 944 1290 788 34.6 31.8 25.3 (1) VOCs were re sampled 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 2015 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Carbon Tetrachloride (5 M9/L) Chloroform (70H9/L) Chloromethane ___(30 pg'L)___ Parameter (GWQS) Methylene Chloride ______(5M9/L)_____ Chloride No GWQS (mg/L) Nitrate, Nitrate + Nitrite ______(10 mg/L)______ TW4-25 nitrate pumping well 2nd Qtr 6/27/07 3rd Qtr 8/15/07 4th Qtr 10/10/07 <1.0 <1.0 <1.0 <1.0 <1.0 2.2 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 395 382 358 17.1 29 17 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 <1.0 <1.0 <1.0 NA <2.0 <1.0 <1.0 <1.0 NA <2.0 <1.0 <1.0 <1.0 NA <2.0 <1.0 <1.0 <1.0 NA <2.0 NA 374 344 333 366 NA 18.7 22.1 18.8 21.3 1st Qtr 3/4/09 2nd Qtr 6/23/09 3rd Qtr 9/14/09 4th Qtr 12/14/09 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 332 328 328 371 15.3 15.3 3.3 14.2 1st Qtr 2/23/10 2nd Qtr 6/14/10 3rd Qtr 8/10/10 4th Qtr 10/15/10 <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 <1.0 296 306 250 312 14.4 16 14 15 1st Qtr 2/16/11 2nd Qtr 5/25/11 3rd Qtr 8/16/11 4th Qtr 11/15/11 <1.0 <1.0 <1.0 <1.0 1.8 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 315 321 276 294 15 16 16 16 1st Qtr 1/16/12 2nd Qtr 5/31/12 3rd Qtr 9/4/12 4th Qtr 10/3/12 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 304 287 334 338 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 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 190 136 119 88.6 9.04 5.24 6 1st Qtr 1/27/14 2nd Qtr 5/19/14 3rd Qtr 8/11/14 4th Qtr 10/21/14 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 85.7 51.1 67 58.1 2.2 1.2 1.6 1 1st Qtr 3/9/15 2nd Qtr 6/8/15 3rd Qtr 8/31/15 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 310 58.3 69.2 14.4 1 1.6 (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 3rd Quarter 2015 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Parameter (GWQS) Carbon Tetrachloride ______(Spg/L) Chloroform (70 M9/L) Chloromethane (30 M9/l>___ Methylene Chloride ______(spg'i)_____ Chloride No GWQS (mg/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 13 5.2 5.4 <1.0 <1.0 <1.0 <1,0 <1.0 <1.0 33 17 22 7.8 9.0 9.6 1st Qtr 2/16/11 2nd Qtr 5/26/11 3rd Qtr 8/17/11 4th Qtr 11/16/11 <1) 12/7/11 <1.0 <1.0 <1.0 NA <1.0 NA 2 2.9 2.8 5.2 <1.0 <1.0 <1.0 NA <1.0 <1.0 <1.0 <1.0 NA <1.0 NA 30 15 19 26 10.0 10.0 11.0 10.0 NA 1st Qtr 1/18/12 2nd Qtr 6/6/12 3rd Qtr 9/11/12 4th Qtr 10/3/12 <1.0 <1.0 <1.0 <1.0 7 4.1 4.9 4.9 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 17 19 19 19 11.0 12.0 9.0 12.0 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 4.9 2.12 2.81 3.37 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 16.6 14.5 17.6 15.9 12.5 13.6 11.7 15.9 1st Qtr 1/29/14 2nd Qtr 5/21/14 3rd Qtr 8/11/14 4th Qtr 10/28/14 <10 <1.0 <1.0 <1.0 1.43 4.23 1.3 2.45 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 16.9 15.4 15 14.6 14.2 12.5 10.8 12.3 1st Qtr 3/12/15 2nd Qtr 6/10/15 3rd Qtr 9/3/15 <1.0 <1.0 <1.0 TW4-27 1st Qtr 1/18/12 2nd Qtr 6/13/12 3rd Qtr 9/4/12 4th Qtr 10/3/12 <1.0 <1.0 <1.0 <1.0 2.37 6.12 4.77 <1.0 <1.0 1.17 <1.0 <1.0 <1.0 9 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 14.4 14.4 14 14.4 11.3 14.2 11 17 21 18 24.0 41.0 37.0 36.0 1st 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 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 18.8 20.3 19 21.8 31.2 29.4 27.2 29.8 1st Qtr 1/23/14 2nd Qtr 5/21/14 3rd Qtr 8/13/14 4th Qtr 10/28/14 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 31.8 20.6 23 31.3 31.1 27.0 24.4 28.2 1st Qtr 3/11/15 2nd Qtr 6/10/15 3rd Qtr 9/2/15 <1.0 <1.0 <1.0 <1.0 <1.0 1.3 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 26.2 26.8 26.8 26.5 24.0 20.9 14.9 17.3 16.2 TW4-28 2nd Qtr 6/19/13 3rd Qtr 8/29/13 4th Qtr 11/6/13 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 44.6 45.3 45.3 1st Qtr 1/22/14 2nd Qtr 5/21/14 3rd Qtr 8/13/14 4th Qtr 10/23/14 <1.0 <1.0 <1.0 <1.0 <1,0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 47.8 45.7 50 52.1 16.9 16.5 14.2 16.5 1st Qtr 3/11/15 2nd Qtr 6/10/15 3rd Qtr 9/2/15 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 52.2 56.4 61.4 19.0 19.0 17.8 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 <1.0 242 262 246 260 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 44.8 37.7 41.4 42.5 4.60 3.52 4.18 4.11 1st Qtr 2/5/14 2nd Qtr 5/22/14 3rd Qtr 8/27/14 4th Qtr 10/29/14 <1.0 <1.0 <1.0 <1.0 258 262 242 290 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 14.9 38.2 41 41 4.63 3.52 3.40 3.64 1st Qtr 3/12/15 2nd Qtr 6/11/15 3rd Qtr 9/3/15 <1.0 <1.0 <1.0 299 329 276 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 40.5 42.5 47.3 4.14 2.95 2.19 (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 2015 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Carbon Tetrachloride ______(s ug/L)______ Chloroform (70 M9/L) Chloromethane (30 ug/L) Parameter (GWQS) Methylene Chloride (S ug/L) Chloride No GWQS (mg/L) Nitrate, Nitrate + Nitrite (10 mg/L) TW4-30 2nd Qtr 6/19/13 3rd Qtr 9/26/13 4th Qtr 11/13/13 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 36 36.3 35.9 1.0 1 1.2 1st Qtr 1/23/14 2nd Qtr 5/22/14 3rd Qtr 8/13/14 4th Qtr 10/23/14 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 36.9 31.9 38 37.1 1.4 1.4 1.5 1.8 1st Qtr 3/11/15 2nd Qtr 6/11/15 3rd Qtr 9/3/15 <1.0 <1.0 <1.0 1.65 2.25 3.27 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 38.3 40.3 44.2 2.15 1.75 1.75 TW4-31 2nd Qtr 6/19/13 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 <1.0 <1.0 <1.0 <1.0 28.4 29.4 28 1.3 1.1 1.3 1st Qtr 1/23/14 2nd Qtr 5/21/14 3rd Qtr 8/13/14 4th Qtr 10/28/14 <1.0 <1.0 <1.0 <1.0 1st Qtr 3/11/15 2nd Qtr 6/10/15 3rd Qtr 9/2/15 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 28.5 26.3 30 37.1 30.6 31.1 30.4 1.3 1.2 1.1 1.8 1.3 1.2 0.9 TW4-32 4th Qtr 11/14/13 <1.0 <1.0 <1.0 <1.0 52.1 4.3 1st Qtr 1/22/14 2nd Qtr 5/21/14 3rd Qtr 8/13/14 4th Qtr 10/23/14 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 54.5 54.9 64 62.6 5.1 5.6 4.2 2.1 1st Qtr 3/11/15 Duplicate TW-65 2nd Qtr 6/10/15 3rd Qtr 9/2/15 <1.0 <1.0 <1.0 <1.0 <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 65.9 62.7 59.6 2.5 2.25 1.2 5.1 TW4-33 4th Qtr 11/14/13 <1.0 126 <1.0 <1.0 47.2 1.82 2.56 1.63 1.50 2.22 1.91 1.62 1.64 1st Qtr 1/30/14 2nd Qtr 5/22/14 3rd Qtr 8/27/14 4th Qtr 10/29/14 <1.0 <1.0 <1.0 <1.0 124 121 104 124 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 43.5 46.8 43 44.2 1st Qtr 3/12/15 2nd Qtr 6/11/15 3rd Qtr 9/3/15 <1.0 <1.0 <1.0 134 127 123 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 44.2 46.6 53.3 TW4-34 4th Qtr 11/14/13 <1.0 <1.0 <1.0 <1.0 19.2 1.64 1st Qtr 1/23/14 2nd Qtr 5/22/14 3rd Qtr 8/13/14 4th Qtr 10/29/14 <1.0 <1.0 <1.0 <1.0 1st Qtr 3/11/15 2nd Qtr 6/11/15 3rd Qtr 9/3/15 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 20.4 17.9 18 17.8 17.7 17.4 15.1 1.93 1.69 1.10 1.16 1.21 0.868 0.458 TW4-35 3rd Qtr 8/27/14 4th Qtr 10/28/14 <1.0 <1.0 1st Qtr 3/11/15 2nd Qtr 6/10/15 3rd Qtr 9/3/15 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 34 34.1 34.9 35.2 35.9 0.2 0.351 0.436 0.452 0.304 TW4-36 3rd Qtr 8/27/14 4th Qtr 10/23/14 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 65 67.3 <0.1 <0.1 1st Qtr 3/11/15 2nd Qtr 6/10/15 3rd Qtr 9/3/15 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 67.2 69.3 76.4 <0.1 <0.1 <0.1 TW4-37(chloroform pumping well) 2nd Qtr 6/8/15 3rd Qtr 8/31/15 18.2 16.6 30,200 119,100 15.7 13.7 1.94 1.04 345 374 35.2 32.4 Shaded indicates concentrations exceeding GWQS. (1) VOCs were resampled because laboratory missed holding time. Table 2 Summary of QA/QC Samples 3rd Quarter 2015 Parameter GWQS Pup TW4-12 icate of MW-32 TW4-65 RPD Pup TW4-23 icate of TW4-25 TW4-70 RPP Chloride none 60.2 58.5 2.9 54.1 55.1 -1.8 Nitrate + Nitrite (as N)10 mg/L 16.4 19.6 -17.8 <0.1 <0.1 # VALUE! Chloroform 70 pg/L <1.0 <1.0 nc <1.0 <1.0 nc ncCarbon tetrachloride 5 pg/L <1.0 <1.0 nc <1.0 <1.0 Chloromethane 30 pg/L <1.0 <1.0 nc <1.0 <1.0 nc ncMethylene Chloride 5 pg/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 Well ID MW4 MW-26 TWN-2 TW4-1 TW4-2 TW4-4 TW4-11 TW4-19 TW4-20 TW4-21 TW4-22 TW4-24 TW4-25 TW4-37 Ave. Chloroform (ug/L)1,200 2,350 1,060 1,060 1,220 1,120 7,860 Chloroform (g/L)1.20E-03 2.35E-03 0.00E+00 1.06E-03 1.06E-03 1.22E-03 1.12E-03 7.86E-03 17,000 1.70E-02 281 7,810 2.81 E-04 7.81 E-03 46.9 4.69E-05 1.04E-07 0 1.00E-07 2.21 E-10 19,100 1.91E-02 422E-05Chloroform (Ibs/L)2.65E-06 5.19E-06 0.00E+00 2.34E-06 2.34E-06 2.70E-06 2.47E-06 1.74E-05 3.76E-05 6.21 E-07 1.73E-05 Chloroform (Ibs/gal) Total gallons pumped 1st qtr 2014 1.00E-05 1.97E-05 0.00E+00 8.86E-06 8.86E-06 1.02E-05 9.37E-06 6.57E-05 1.42E-04 2.35E-06 6.53E-05 89,521 21,042 48,617 23,652 21,587 64,333 3,584 116,504 17,657 125,285 24,617 3.92E-07 66,313 0.03 ....0.002 8.36E-10 124,137 666 o.oc 1.60E-04 118,064 18.86lbs of chloroform removed 0.90 0.41 0.00 0.21 0.19 0.66 0.03 7.66 2.51 0.29 1.61 0.13Gallons of chloroform removed 0.07 0.03 0.00 0.02 0.02 0.05 0.00 0.62 0.20 0.02 1.53 total lbs of chloroform removed 33.4 total gallons of chloroform removed 2.71 Tabel 3 Chloroform Mass Removal Calculations for the 3rd Qurater 2015 DUSA White Mesa Mill, Bland, Utah Well ID MW4 MW-26 TWN-2 TW4-1 TW4-2 TW4-4 TW4-11 TW4-19 TW4-20 TW4-21 TW4-22 TW4-24 TW4-25 TW4-37 Ave. Chloroform (ug/L) Chloroform (g/L) Chloroform (Ibs/L) Chloroform (Ibs/gal) Total gallons pumped 3rd qtr 2015 lbs of chloroform removed Gallons of chloroform removed 1,200 1.20E-03 2.65E-06 1.00E-05 89,521 0.90 0.07 2,350 2.35E-03 5.19E-06 1.97E-05 21,042 0.41 0.03 0.00E+00 0.00E+00 0.00E+00 48,617 0.00 0.00 1,060 1.06E-03 2.34E-06 8.86E-06 23,652 0.21 0.02 1,060 1.06E-03 2.34E-06 8.86E-06 21,587 0.19 0.02 1,220 1.22E-03 2.70E-06 1.02E-05 64,333 0.66 0.05 1,120 1.12E-03 2.47E-06 9.37E-06 3,584 0.03 0.00 7,860 7.86E-03 1.74E-05 6.57E-05 116,504 7.66 0.62 17,000 1.70E-02 3.76E-05 1.42E-04 17,657 2.51 0.20 281 2.81 E-04 6.21 E-07 2.35E-06 125,285 0.29 0.02 7,810 7.81 E-03 1.73E-05 6.53E-05 24,617 1.61 0.13 46.9 4.69E-05 1.04 E-07 3.92E-07 66,313 0.03 0.002 0 1.00E-07 2.21E-10 8.36E-10 124,137 0.00 0.00 19,100 1.91E-02 4.22E-05 1.60E-04 118,064 18.86 1.53 total lbs of chloroform removed 33.4 total gallons of chloroform removed 2.71 Chloroform Pumping Wells Nitrate Pumping Wells