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HomeMy WebLinkAboutDRC-2013-003037 - 0901a068803b291f*V>p riTr-t. V\ OF THj^. 3 505 asm State of Utah GARY R. HERBERT Governor GREG BELL Lieutenant Governor Department of Environmental Quality Amanda Smith Executive Director DIVISION OF RADIATION CONTROL Rusty Lundberg Director "DRC-2013-003037" MEMORANDUM TO: FROM: DATE: SUBJECT: Phil Goble r ^ ^ 1 / Dean Henderson August 2, 2013 | Review of the 1st Quarter 2013 Chloroform Monitonng 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 May 28, 2013, 1st Quarter 2013 Chloroform Monitonng 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 August 24, 2012. • 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 TW 4-15), MW-32 (formerly TW4-17), TW4-26, and TW4-27. It should be noted that four new monitor wells TW4-28, TW4-29, TW4-30, and TW4-31 were dnlled and installed in the 1st quarter 2013 dunng the week of March 4, 2013 as part of a nitrate contamination investigation at wells TW4-12 and TW4-27.. These new wells well be sampled m the 2nd quarter 2013 monitoring event. The following monitonng 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): 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 Pnnted on 100% recycled paper Page 2 Wells: MW-32, TW4-1, TW4-5, TW4-7, TW4-8, TW4-9, TW4-11, TW4-12, TW4-16, TW4- 18,TW4-21,andTW4-23. 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, TW4-10, TW4-13, TW4-14, TW4-26, and TW4-27. 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 chlonde, Chlonde and Nitrate plus Nitrite as Nitrogen. Use of analytical methods is consistent with the requirements of the QAP requirements. QAQC Holding Times The method holding times for each parameter for samples collected at each monitor well were received and analyzed within the required holding times in the QAP. Receipt Temperature All samples were received within the required QAP temperature limit of 6° C. Detection Limits All analytes were measured and reported to the required reporting limits. However, several sets of sample results had the reporting limit raised for at least one analyte due to matnx 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 TW4-16 and its duplicate sample TW4-65 and TW4-18 and its duplicate sample TW4-70. All analytical results for both the sample/duplicate pairs were withm the 20% acceptance limits as required in the QAP (see Table 2 below). Groundwater Head Monitoring Depth to groundwater was measured in the following wells and/or piezometers, as required in Part I.E.3 of the Permit: • The quarterly groundwater compliance monitonng wells. • Existing monitonng well MW-4 and all of the temporary chloroform investigation wells. • Piezometers P-l, P-2, P-3, P-4 and P-5. • MW-20 and MW-22. • Nitrate monitonng wells. • The DR piezometers which were installed dunng the Southwest Hydrologic Investigation. Page 3 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. 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 mass removed in 1st quarter 2013 is 13.7 lbs. (see Table 3 Attached). 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. tnp 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 histonc 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 summanzed 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 monitonng conducted dunng the quarter. f) Copies of DUSA field records, laboratory reports and chain of custody forms. Page 4 Evaluation of the Chloroform Contaminate Plume and Its Associated Contaminants Bounding Chloroform Plume Groundwater monitonng data for the 1st quarter 2013 monitonng event appeared to show that the chloroform contaminate plume and associated contaminants, carbon tetrachloride, chloromethane, and methylene chlonde is bound in all directions by wells that have a chloroform concentration of <70 ug/L (GWQS = 70 |ig/L). However, during the review of this Report on July 25,2013 in a conference call EFR notified DRC that the new monitor well TW4-29, that was installed on as part of a nitrate contamination investigation at well TW4-27 and sampled in June 2013, had chloroform concentrations exceeding GWQS (70 ug/L) at 262 ug/L. TW4-29 is approximately 200 feet south of well TW4-27 that apparently bound the chloroform plume to the south with non-detectable chloroform concentrations (<1.0 ug/L). On July 29, 2013 EFR submitted a letter with proposed actions that include the installation of two new monitor wells in the vicinity of TW4-29 to investigate the chloroform plume migration. On August 2, 2013 DRC sent EFR a conditionally approval letter on their proposed actions. Monitor Wells Exceeding Chloroform Concentrations of 70ug/L There are 7 monitor wells exceeding chloroform concentrations of 70ug/L. Monitor well TW4-1, TW4-2, TW4-7, TW4-10, TW4-11, and TW4-21 have decreasmg trends. Monitor Wells with Chloroform Concentrations Between 1 ug/L and 70ug/L There are nine monitor wells that have chloroform concentrations of <70ug/L. Monitor well TW4-5, TW4- 6, TW4-8, TW4-9, TW4-18, and TW4-26 have decreasing trends. 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 wells TW4-24 and TW4-25 have non-detectable chloroform concentrations (1.0 ug/L). Monitor Wells Below the Detection Limit 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, and TW4-27 (see Table 1 below). Nitrate, Nitrate + Nitnte ("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 contmue to exceed the GWQS (10 mg/L). Three wells have been installed down-gradient of well TW4-27 and one new well was installed down-gradient of TW4- 12. These wells have been sampled and EFR will report the data m the 2nd Quarter 2013 Chloroform Monitonng Report for the chloroform contamination investigation and submit a Contamination Investigation Report. Conclusions on Compliance with the Permit and QAP Per the DRC review it appears that the Report complies with Permit and QAP. Therefore a letter will be drafted for the Director Signature, notifying EFR of the review and closmg-out of the 1st Quarter 2013 Chloroform Monitoring Report for the chloroform contamination investigation. Page 5 References Energy Fuels Resources (USA) Inc., June 7, 2012 White Mesa Uranium Mill, Ground Water Monitonng Quality Assurance Plan (Revision 7.2). Energy Fuels Resources (USA) Inc., February 18, 2013 White Mesa Uranium Mill Chloroform Monitoring Report 1st Quarter 2013 (October through December 2012). Energy Fuels Resources (USA) Inc., February 6, 2013,14-day Notification for Installation of Four Additional Monitoring Wells. Energy Fuels Resources (USA) Inc., July 29, 2013, Letter, Subject: Utah Groundwater Discharge Permit ("GWDP") UGW370004 Follow-up and response to February 14,2013 Confirmatory Action Letter State of Utah Division of Water Quality Department of Environmental Quality, August 24,2012, 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. State of Utah Division of Water Quality Department of Environmental Quality, January 2009, Stipulated Consent Agreement, UDEQ Docket No. UGW-09-03. Utah Division of Radiation, February 14, 2013, Nitrate Contamination Investigation. Nitrate Concentrations Exceeding the Groundwater Quality Standard in Monitor Wells TW4-12 and TW4-27. Confirmatory Action Letter. Utah Division of Radiation, August 2, 2013, Letter, Subject: Nitrate Contamination Investigation at Monitor Wells TW4-12 and TW4-28. Chloroform Contamination Investigation at Monitor Well TW4-29. Conditional Approval. TABLE 1 Historic Summary Of Monitoring Parameters Up To The 1st Quarter 2013 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Parameter GWQS Carbon Tetrachloride (5 pg/L) Chloride (mg/L) No GWQS Chloroform (70 ug/L) Chloromethane (30 Mg/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 Qtr 2/23/11 2nd Qtr 6/1/11 3rd Qtr 8/17/11 4th Qtr 11/16/11 lstQtr 1/23/12 2nd Qtr 6/6/12 3rd Qtr 9/4/12 4th Qtr 10/4/12 1st Qtr 2/11/13 NA NA <10 <SO <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 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 2,900 3,170 3,000 3,100 3,000 2,820 2,830 2,300 2,000 2,600 2,300 2,400 2,500 1,800 2,100 2,200 1,800 2,000 1,800 1,600 2,100" 1,900 1,500 1,700 1,700 1,700 1,600 1,500 1,500 1,300 1,670 NA NA <10 <so <so <50 <50 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 1 4 NA NA <10 <so <50 <50 <50 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 MW-4AfTW4-A) 1st Qtr 3/16/05 2nd Qtr 5/25/05 3rd Qtr 8/31/05" 4th Qtr 12/7/05 1st Qtr 3/9/06 2nd Qtr 6/14/06 3rd Qtr 7/20/05 4th Qtr 11/8/05 1st Qtr 2/28/07 NA NA <10 <so <50 <50 <50 3,700 3,740 3,800 3,000 3,700 3,300 3,190 3,370 2,500 NA NA <10 <50 <SO <SO <50 <1 0 <1 0 NA NA <10 <50 <50 <SO <50 <1 0 <1 0 Well abandonded 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 NA NA <5 0 <S0 <50 <SO <50 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA <2 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <10 <1 0 <1 0 <1 0 <1 <1 <1 1 2 NA NA NA NA 55 52 52 65 54 56 49 57 57 49 57 44 64 49 48 46 60 57 40 49 65 57 88 58 69 98 73 73 ' 68 819 310 442 960 1,000 1,100 830 2,170 282 570 1,400 2,000 930 1,300 630 NA 1,700 950 410 850 1,100 730 1,600 2,200 970 450 1,800 720 1,800 2,400 3,100 1,200 2,120 NA NA 54 <50 <50 <so <50 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA <2 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 <1 <1 NA NA <5 0 <so <50 <SO <50 NA <1 0 26 5 5 13 36 14 40 53 24 100 51 12 30 40 19 21 65 36 1 3 72 29 16 21 31 4 9 34 NA (1) VOCs were resampled because laboratory missed holding tme NA = not analyzed NS = not sampled TABLE 1 Historic Summary Of Monitoring Parameters Up To The 1st Quarter 2013 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Parameter GWQS Carbon Tetrachloride (5 pg/L) Chloride (mgA.) No GWQSj Chloroform (70 pg/L) Chloromethane (30 pgA) Methylene Chloride (5 pg/L) Nitrate, Nitrate + Nitrite (10 mg/L) Shaded indicates concentrations exceeding GWQS Bold and red = highest concentraton since montonng started Bold and blue = lowest concentraton since montonng started Bold and italics indicates the MDL exceeded the GWQS 1st Qtr = January - March 2nd Qtr = Apnl - June 3rd Qtr = July - September _ 4th Qtr = October - December TABLE 1 Historic Summary Of Monitoring Parameters Up To The 1st Quarter 2013 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Parameter GWQS Carbon Tetrachloride (5 pg/L) Chloride (mg/L) No GWQS Chloroform (70 pg/L) Chloromethane (30 pg/L) Methylene Chloride (5 pg/L) 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 3rdQtr8/16/10 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) 12/7/11 lstQtr 1/18/12 2nd Qtr 6/22/12 3rd Qtr 9/5/12 4th Qtr 10/10/12 1st Qtr 2/11/13 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 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 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA NA <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 32 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 •d 0 <1 0 <1 0 <1 0 <1 0 <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 <1 0 <1 <1 0 <1 0 <1 0 <1 0 < 1 <1 0 <1 0 <0 05 < 1 <0 1 <0 1 <0 1 <0 1 <0 1 <01 <0 1 <0 1 <0 1 <0 1 <0 1 <01 <01 <0 1 <0 1 <0 1 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 Qtr8/18/10 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 lstQtr 1/24/12 2nd Qtr 6/14/12 3rd Qtr 9/28/12 4th Qtr 10/4/12 1st Qtr 2/13/13 NA NA <10 <so <so <50 <S0 <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 3 66 52 49' 48 51 47 47 45 43 43 39 39 35 41 37 37 36 41 35 40 35 40 41 35 36 40 38 42 39 40' 37 6 2,700 2,900 2,400 2,700 2,200 2,840 2,260 1,900 1,900 2,300 2,000 2,000 1,900 1,700 1,700 'l',700 1,500 1,700 1,400 1,300 1,600 1,600 1,500 "1,300 1,200 1,300 1,500 1,300 1,100 1,320 NA NA <10 <so <so <so <so <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <10 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA NA <10 <so <so <50 <50 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 (1) VOCs were resampled because laboratory missed holding NA = not analyzed NS = not sampled Shaded indicates concentratons exceeding GWQS Bold and red = highist concentraton since montonng started Bold and blue = lowest concentraton since montonng started Bold and italics indicates the MDL exceeded the GWQS 1st Qtr = January - March 2nd Qtr = Apnl - June 3rd Qtr = July - September 4th Qtr = October - December tme TABLE 1 Historic Summary Of Monitoring Parameters Up To The 1st Quarter 2013 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Carbon Tetrachloride (5 MQ/L) Chloride (mgA.) No GWQS Parameter GWQS Chloroform (70 pgA.) Chloromethane (30 pgA.) Methylene Chloride (5 pg/L) Nitrate, Nitrate + Nitrite (10 mgA.) 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 3/3/1 o" 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 NA NA <10 <so <50 <50 <50 NA 23 1 8 2 5 2 2 21 2 3 22 2 4 24 2 2 " 2 2 2 2 26 25 21 2 4 22 1 61 28 2 21 1 8 2 517' NA NA 3,700 3,750 3,900 3,500 3,800 3,200 3,420 2,300 3,000 3,200 3,300 3,100 2,800 3,200 3,100 2,800 3,000 2,600 3,300 3,300 3,000 3,100 3,000 2,400 3,900 2,500 2,500 2,900 3,100 3.580 NA NA <10 <S0 <so <so <so <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 NA NA <10 <SO <SO <SO <50 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA <2 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA 77 86 80 78 75 7 1 74 76 73 78 73 69 69 74 7 1 80 65 64 66 64 68 87 66 65 70 68 60 70 71 77 40 76 81 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 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 NA NA NA 26 26' 26 26 23< 22 23 24 27 21 19 19 22 21 20 21 22 ' 23 24 22 261 23 23 23 23 21 24 25 25 23 7 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 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 <1 0 <1 0 <1 0 <1 0 <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 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 35 37 35 33 33 7 1 29 1 5 31 33 31 28 28 29 27 26 25 29 28 26 28 30 31 33 35 37 40 44 71 44 49 48 51 NA = not analyzed NS = not sampled Shaded indicates concentrations exceeding GWQS Bold and red = highist concentraton since montonng started Bold and blue = lowest concentraton since montonng started Bold and italics indicates the MDL exceeded the GWQS 1 st Qtr = January - March 2nd Qtr = Apnl - June 3rd Qtr = July - September 4th Qtr = October - December TABLE 1 Historic Summary Of Monitoring Parameters Up To The 1st Quarter 2013 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Parameter GWQS Carbon Tetrachloride (5 pg/L) Chloride (mg/L) No GWQS Chloroform (70 pg/L) Chloromethane (30 pg/L) Methylene Chloride (5 pg/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 lstQtr 1/23/12 2nd Qtr 6/6/12 3rd Qtr 9/4/12 4th Qtr 10/3/12 1st Qtr 2/11/13 NA NA <10 <so <50 <50 <50 NA <2 0 <1 0 <1 0 <1 0 1 2 1 1 NA NA NA NA NA 3,100 2,400 2,800 2,900 2,600 2,850 2,670 2,200 2,400 2,700 2,500 2,800 2,500 2.200 2,500 2,200 1,800 2,000 1,700 1,700 2,100 1,700 1,800 1,700 1,500 1,500 1,200 1,500 1,600 1,400 1,460 NA NA <10 <50 <50 <50 <50 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA <2 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0* <1 0 <1 0 <1 0 NA NA <10 <50 <50 <50 <50 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA <2 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA 100 11 3 99 10 2 ' '95 86 97 101 90 94 95 95 "92 10 8 88 10 1 102 82 84 76 66 76 73 7 1 70 70 66 70 7 1 7 1 7 1 70 74 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 1 St 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 2/25/10 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 lstQtr 1/18/12 2nd Qtr 6/6/12 3rd Qtr 9/11/12 4th Qtr 10/3/12 1st Qtr 2/13/13 NA NA <2 5 <2 5 <2 5 <2 5 <1 0 <1 0 <1 0" <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0" <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 56 521 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' 113 82 63 66 51 537 47 1 35 26 92 94 11 93 11 10 12 13 12 85 13 12 12 11 10 9 10 79 76 84 12 8 108 NA NA <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 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 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 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 7 1 70 72 70 72 75 60 58 80 81 77 82 (1) VOCs were resampled because laboratory missed holding NA = not analyzed NS = not sampled Bold and red = highist concentration since montonng started Bold and blue = lowest concentraton since montonng started Shaded indicates concentratons exceeding GWQS Bold and italics indicates the MDL exceeded the GWQS 1st Qtr = January - March 2nd Qtr = Apnl - June 3rd Qtr = July - September 4th Qtr = October - December tme TABLE 1 Historic Summary Of Monitoring Parameters Up To The 1st Quarter 2013 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Parameter GWQS Carbon Tetrachloride (5 ugA.) Chloride (mg/L) No GWQS Chloroform (70 ug/L) Chloromethane (30 pg/L) Methylene Chloride (5 pg/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 lstQtr 1/18/12 2nd Qtr 6/13/12 3rd Qtr 9/11/12 4th Qtr 10/3/12 1st Qtr 2/13/13 NA NA <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA NA NA <1 0 32 31' 30 37 65 32 38 36 35 33 35 35 33 35 37 37 41 45' 33 31 41 40' 42 39 36 33 38 40 "21 41 40 4' 25 10 17 31 19 11 42 8 46 11 18 18 52 24 39 37 "8"1 120 280 250 1000 590 630 420 •47 9.6 16 21 50 38 47 69 9 6 89 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 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 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 02 04 08 09 1 2 1 0 06 1 4 1 8 06 07 08 1 1 09 1 1 1 0 22 27 50 6 1 1 8 25 39 43 07 03 03 08 08 07 02 0 1 02 02 TW4-7 1st Qtr 3/16/05 2nd Qtr 5/25/05 3rd Qtr 8/31/05 4th Qtr 12/7/05 Ist'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 2ndQtr6/1/11 3rd Qtr 8/18/11 4th Qtr 11/29/11 lstQtr 1/19/12 2nd Qtr 6/14/12 3rd Qtr 9/13/12 4th Qtr 10/4/12 1st Qtr 2/13/13 NA NA <10 <50 <50 <50 <50 NA <20 <1 0 <1 0 <1 0 <1 0 1 <1 0 <ib <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA 52 48 47 51 49 47 45 44 45 43 43 35 40 35 37 37 37 35 31 36 38 45 35 37 37 37 41 40 41 37 7 NA 3,100 2,700 3,100 2,500 1,900 2,200 2,140 2,160 1,830 2,600 2,300 1,900 2,200 1,800 1,600 2,500 1,800 1,400 1.500 1,300 1,200 1,100 1,500 1,100 1,300 1,200 1,200 1,000 1,000 790 870 940 940 NA NA <10 <SO <so <50 <SO <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 <10 <10 <1 0 <1 0 NA NA <10 <so <50 <SO <SO <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 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 39 40 38 38 35 (1) VOCs were resampled because laboratory missed holding (2) Results of the TW4-70 the duplicate sample for TW4-6 NA = not analyzed NS - not sampled Shaded indicates concentratons exceeding GWQS Bold and red = highest concentraton since montonng started Bold and blue = lowest concentraton since montonng started Bold and italics indicates the MDL exceeded the GWQS 1st Qtr = January - March 2nd Qtr = Apnl - June 3rd Qtr = July - September 4th Qtr = October - December tme TABLE 1 Historic Summary Of Monitoring Parameters Up To The 1st Quarter 2013 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Parameter GWQS Carbon Tetrachloride (5 pgA.) Chloride (mgA.) No GWQS Chloroform (70 pgA.) Chloromethane (30 pg/L) Methylene Chloride (5 pg/L) Nitrate, Nitrate + Nitrite (10 mgA.) [TW4-8 1st Qtr 3/16/05 2nd Qtr 5/25/05 3rd Qtr 8/31/05 4th Qtr 12/7/05 1st Qtr 3/9/06 2nd Qtr 6/14/06 3rd Qtr 7/20/06 4th Qtr 11/8/06 1st Qtr 2/28/07 2nd Qtr 6/27/07 3rd Qtr 8/15/07 4th Qtr 10/10/07 1st Qtr 3/28/08" 2nd Qtr 6/25/08 3rd Qtr 9/10/08 4th Qtr 10/15/08 1st Qtr 3/4/09 2nd Qtr 6/23/09 3rd Qtr 9/14/09 4th Qtr 12/17/09 1st Qtr'2/24/16 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 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 <Tb" <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 10 11 25 25 1 5 35 NA NA <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 1 7 51 57 42 45 46 52 45 46 45 45 44 48 47 46 6' <1 0 <1 0 <1 0 <10 <1 0 <1 0 <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 <io" <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 <10 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <01 <1 0 <1 b <1 0 < 1 <1 0 <1 0 <0 05 <0 05 <0 1 <0 1 <0 1 <0 1 <0 1 <0 1 <01 0 1 <0 1 TW4-9 1st Qtr 3/16/05 2nd Qtr 5/25/05 3rd Qtr 8/31/05 4th Qtr 12/7/05 1st Qtr 3/9/06 2nd Qtr 6/14/06 3rd Qtr 7/20/06 4th Qtr 11/8/06 1st Qtr 2/28/07 2nd Qtr 6/27/07 3rd Qtr 8/15/07 4th Qtr 10/10/07 1st Qtr 3/28/08 2nd Qtr 6/25/08 3rd Qtr 9/10/08 4th Qtr 10/15/08 1st Qtr 3/4/09 2nd Qtr 6/23/09 3rd Qtr 9/14/09 NA NA <1 0 <1 0 <1 0 <1 0 <1 0 <i 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 19 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 29 26 27 NA NA <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 <T6"' <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 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 lstQtr 1/18/12 2nd Qtr 5/31/12 3rd Qtr 8/30/12 4th Qtr 10/3/12 1 st Qtr 2/7/13" <1 0 <1 6 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <10 <1 0 <1 0 <1 0 <1 0 37 47 33 40 34 41 38 21 38 28 23 22 21 20 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) VOCs were resampled because laboratory missed holding tme NA = not analyzed NS = not sampled Shaded indicates concentratons exceeding GWQS Bold and red = highest concentraton since montonng started Bold and blue = lowest concentraton since montonng started Bold and italics indicates the MDL exceeded the GWQS 1 st Qtr = January - March 2nd Qtr = Apnl - June 3rd Qtr = July - September 4th Qtr = October - December TABLE 1 Historic Summary Of Monitoring Parameters Up To The 1st Quarter 2013 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Parameter GWQS Carbon Tetrachloride (5 ug/L) Chloride (mg/L) No GWQS Chloroform (70 ug/L) Chloromethane (30 pg/L) Methylene Chloride (5 pg/L) Nitrate, Nitrate + Nitrite (10 mg/L) TW4-10 1st Qtr 3/16/05 2nd Qtr 5/25/05 3rd Qtr 8/31/05 4th Qtr 12/7/05 1stQtr3/9/06 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 NA NA <2 5 <2 5 <5 0 <5 0 <5 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA <2 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <ib NA NA NA NA 52 50' 54 61 58 2 54 59 59 55 58 51 61 64 62 51 51 48 42 38 52 32 42 41 45 40' 46 44 45 49 1 140 62 4 ' 110 300 190 300 504 452 500 350 660 470 620 720 660 NA 1,100 910 300 460 220 100 1100 620 280 180 110 79 130 140 154 NA NA <2 5 <5 0 <5 0 <5 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <10 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 62 1 6 NA NA <2 5 <2 5 <5 0 <5 0 <5 0 <1 0 *<1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA <2 0 <1 0 <1 0 <1 0 <1 0 <1 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 NA TW4-11 1st Qtr 3/16/05 2nd Qtr 5/25/05 3rd Qtr 8/31/05 4th Qtr 12/7/05 1st Qtr 3/9/06 2nd Qtr 6/14/06 3rd Qtr 7/20/06 4th Qtr 11/8/06 1st Qtr 2/28/07 2nd Qtr 6/27/07 3rd Qtr 8/15/07 4th Qtr 10/10/07 1st Qtr 3/28/08 2nd Qtr 6/25/08 3rd Qtr 9/10/08 4th Qtr 10/15/08 4th Qtr 11/18/09 1st Qtr 3/11/09 2nd Qtr 6/23/09 3rd Qtr 9/14/09 4th Qtr 12/29/09 1st Qtr 3/3/10 2nd Qtr 6/14/10 3rd Qtr 8/12/10 4th Qtr 10/15/10 1st Qtr 2/23/11 2nd Qtr 6/1/11 3rd Qtr 8/17/11 4th Qtr 11/16/11 1st Qtr 1/24/12 2nd Qtr 6/13/12 3rd Qtr 9/13/12 4th Qtr 10/3/12 1st Qtr 2/13/13 NA NA <10 <100 <50 <50 <50 <1 0 <1 0 <1 0 NA <2 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA NA NA NA 3 23 58 56 56 55 55 54' 53 53 53 63 46 42 47 49 44 49 46J 42 40 43 49 46' 49 ' 48 - 46 43 52 49 50 47 3 NA 4,400 3,590 4,400 4,400 4,400 ' 4,300 4,080 3,660 3,600 3,800 4,400 640 900 i.obo ' 1,000 980 1,000 860 820 820 800 720 1,000 930 820 1500 610 660 740 730 867 NA NA <10 <100 <50 <50 <50 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA <2 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 27 NA NA <10 <100 <50 <50 <50 <1 0 <1 0 <1 0 <1 0 <1 0 NA <2 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 1 2 NA (1) VOCs were resampled because laboratory missed holding NA = not analyzed NS - not sampled Shaded indicates concentrations exceeding GWQS Bold and red = highest concentration since montonng started Bold and blue = lowest concentration since montonng started Bold and italics indicates the MDL exceeded the GWQS 1st Qtr = January - March 2nd Qtr = Apnl - June 3rd Qtr = July - September 4th Qtr = October - December tame TABLE 1 Historic Summary Of Monitoring Parameters Up To The 1st Quarter 2013 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Carbon Tetrachloride (5 pg/L) Chloride (mg/L) No GWQS Parameter GWQS Chloroform (70 ug/L) Chloromethane (30 pgA) Methylene Chloride (5 pg/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 2/13/13 NA NA <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 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 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 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 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 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA NA <1 0 <1 0 <1 0~ <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 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 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <10' <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <i 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 3 1 NA NA <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 1 4 1 6 15 1 4 1 3 1 4 14 1 4 1 5 1 5 1 4 1 4 1 6 27 27 25 24 38 51 36 40 90 80 65 70 68 80 77 100 42 43 46 43 42 49 43 08 40 46 44 4 1 38 42 43 46 37 1 2 47 4 1 43 52 56 58 55 64 52 59 55 60 62 59 63 NA = not analyzed NS = not sampled Shaded indicates concentratons exceeding GWQS Bold and italics indicates the MDL exceeded the GWQS 1st Qtr = January - March 2nd Qtr = Apnl - June 3rd Qtr = July - September 4th Qtr = October - December TABLE 1 Historic Summary Of Monitoring Parameters Up To The 1st Quarter 2013 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Parameter GWQS Carbon Tetrachloride (5 ug/L) Chloride (mgA.) No GWQS, Chloroform (70 ug/L) Chloromethane (30 pg/L) Methylene Chloride (5 M0/1-) 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 lstQtr 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 NS NS NS NS NS NS NS <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 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 NS NS NS NS NS NS NS NS <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NS NS NS NS NS NS NS <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NS NS NS NS NS NS NS <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 o' <1 0 24 23 1 4 1 1 08 04 1 6 1 38 0 76 1 6 1 4 1 5 1 4 25 29 28 29 1 8 1 4 26 1 7 1 9 33 39 39 46 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) 12/7/11 lstQtr 1/18/12 2nd Qtr 5/26/11 3rd Qtr 8/30/12 4th Qtr 10/3/12 1st Qtr 2/7/13 NA NA <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 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 <1 0 <1 0 <1 0 <1 0 <1 0 240 212 85 14 39 13 52 13 6 87 26 7 1 1 4 11 10 39 21 43 3 15 16 92 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA NA <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA NA 32 26 1 1 24 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <10 43 59 21 89 27 92 66 1 8 51 1 ' 26 14 66 <01 <01 <0 1 1 4 3 1 9 27 56 123 99 54 44 <01 1 5 10 5 98 96 89 88 52 42 47 46 33 7 5 1 7 04 0 1 <0 1 <0 1 <0 1 <0 1 (1) VOCs were resampled because laboratory missed holding time NA = not analyzed NS = not sampled Bold and red = highest concentration since montonng started Bold and blue = lowest concentraton since montonng started Shaded indicates concentratons exceeding GWQS Bold and italics indicates the MDL exceeded the GWQS 1st Qf = January - March 2nd Qtr = Apnl - June 3rd Qtr = July - September 4th Qtr = October - December TABLE 1 Historic Summary Of Monitoring Parameters Up To The 1st Quarter 2013 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Parameter GWQS Carbon Tetrachloride (5 ug/L) Chloride (mg/L) No GWQS, Chloroform (70 pg/L) Chloromethane (30 ug/L) Methylene Chloride (5 ug/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 1st Qtr 3/9/06 2nd Qtr 6/14/06 3rd Qtr 7/20/06 4th Qtr 11/8/06 1st Qtr 2/28/07 2nd Qtr 6/27/07 3rd Qtr 8/15/07 4th Qtr 10/10/07 1st Qtr 3/28/08 2nd Qtr 6/25/08 3rd Qtr 9/10/08 4th Qtr 10/15/08 1st Qtr 3/4/09 2nd Qtr 6/23/09 3rd Qtr 9/14/09 " 4th Qtr 12/22/09 1st Qtr 2/24/10 2nd Qtr 6/14/10 3rd Qtr 8/12/10 4th Qtr 10/15/10 1st Qtr 2/22/11 2nd Qtr 5/26/11 3rd Qtr 8/17/11 4th Qtr 11/16/11 (1) 12/7/11 lstQtr 1/18/12 2nd Qtr 6/13/12 3rd Qtr 9/11/12 4th Qtr 10/3/12 1st Qtr 2/13/13 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 <1 0 NA NA NA 41 36 35 35 34 30' 28 32 27 23 23 26 30 29 30 26 -30 41' 35 37 50 52 36 23 23 18 30 26 27 231 38 29 8 39 14 12 12 108 12 5 9 2* 8 89 74 64 57 8 94 11 16 13 82 69 29 29 30 39 26 29 28 25 24 ' 38 30 349 <1 0 <1 0 <f 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA NA <1 0 <1 0 <1 0 <1 0 <1 0 <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 <1 0 <1 0* <1 0 <1 0 <1 0 <1 0 14 1 129 133 73 59 47 6 1 57 51 49 50 44 07 46 49 52 52 62 59 54 51 90 90 100 10 0 90 46 63 "44 66 66 60 56 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 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 NA NA <5 0 <SO <so <so <so NA NA NA 81 86 116 Did not sample 1 6 1 3 1 9 1 9 2 9 <1 0 86 12 12 1 2 15 16 13" " 42 49 1 3 17 83 21 " 54 15 1 1 35 4 5 15 123 134 133 129 132 131 128 113 124 127 132 43 124 144' 132' 142 146 135' 148 148' 148^ 138' 149 149 150 164' 2,200 1,200 1,400 2,800 1,200 1,100 1,120 1,050 1,200 1,100 1.100 1,800 1,000 3,600 4.200 1,100 990 4.700 S40 1,800 2,000 1.200 3,400 4,000 970 2,200 650 460 950 1500 4,210 NA NA <5 0 <50 <50 <so <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 <10 <1 0 <1 0 <1 0 26 NA NA <5 0 <50 <50 <50 <50 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <i"o <1 0 <1 0 <1 0 <1 0 <1 0 <1.0 <01 53 57 46 4 52 43 46 4 4 1 4 2 2 28 352 47 8 32 24 <0 1 '267 2 44 59 27 17 0 120 30 50 06 24 25 4 1 80 (1) VOCs were resampled because laboratory missed holding NA = not analyzed NS = not sampled Bold and red = highest concentration since montonng started Bold and blue = lowest concentration since montonng started Shaded indicates concentratons exceeding GWQS Bold and italics indicates the MDL exceeded the GWQS 1st Qtr = January - March 2nd Qtr = Apnl - June 3rd Qtr = July - September 4th Qtr = October - December tme TABLE 1 Historic Summary Of Monitoring Parameters Up To The 1st Quarter 2013 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Carbon Tetrachloride (5 pg/L) Parameter GWQS Chloride (mgA.) No GWQS Chloroform (70 pg/L) Chloromethane (30 pg/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 NA <10 <250 <500 <500 <1000 NA _71 " 3T 22 3 5 68 9* 13 15 5 7* 49 8 4 14 2 7 11 12 20 27 10 73 72 10* 33 26 22 19 6 131 120 235 134 124 124 112 117 170 132 191 156 168 164 164 153 187i 179' 200 196 203 220* 177 207 186 207* 262 289 302 252' Monitor well was not installed NA NA 39,000 3,800 19,000 9,200 61,000 5,300 11,000 4,400 1,800 5,200 9,000 13,000 30,000 21,000 8,200 6,800 13,000 15,000 3,500 18,000 15,000 24,000 31,000 8,100 3,800 7,900 11,000 36,000 13,000 19,000 18.500 NA <10 <250 <500 <500 <1000 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <10 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 1 9 <10, <2S0 <500 <500 <1OO0 <1 0 NA <1 0 <1 0 <1 0 1 21 22 /1 1* 1 8 1 9 * 15 1 2 37 52 4 2 44 30 32 37 22 " 5 5 19 0 21 31 25 13 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 NA <1 0 <1 0 <1 0 <1 0 NA NA NA 353 347' 318 357 296 306 327 300 288 331' 271 244 284 279 291 281 256 Monitor well was not installed NA NA 192 86 120 120 108 139 160 300 140 120 390 180 120 170 180 200 200 160 NA <5 0 <1 0 <2 5 <2 5 <2 5 <1 0 <1 0 <1 0' <1 0 <1 0 <1 0 <1 0 <1 0 NA <2 0 <1 0 <1 0 <1 0 <1 0 <5 0 <1 0 <2 5 <2 5* <2 5 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA <2 0 <1 0 <1 0 <1 0 <1 0 NA 1st Qtr 2/25/10 2nd Qtr 614/10 3rd Qtr 8/13/10 4th Qtr 10/15/10 <1 0 <1 0 92 1 2 228 266 278 210 170 210 390 266 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <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 lstQtr 1/19/12 2nd Qtr 6/13/12 3rd Qtr 9/13/12 4th Qtr 10/4/12 1st Qtr 2/13/13 1 2 48 6 3 67 6 4 54 6 7 5 25 303 290 287 287 228 285 142 270 221' 230 290 460 390 420 400 410 390 282 <1 0 <1 0 <10' <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) VOCs were resampled because laboratory missed holding NA = not analyzed NS = not sampled Bold and red = highest concentration since montonng started Bold and blue = lowest concentraton since montonng started Shaded indicates concentratons exceeding GWQS Bold and italics indicates the MDL exceeded the GWQS 1 st Qtr = January - March 2nd Qtr = Apnl - June 3rd Qtr = July - September 4th Qtr = October - December tme TABLE 1 Historic Summary Of Monitoring Parameters Up To The 1st Quarter 2013 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Parameter GWQS Carbon Tetrachloride (5 ug/L) Chloride (mg/L) No GWQS, Chloroform (70 pg/L) Chloromethane (30 pg/L) Methylene Chloride (5 pg/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 11/16/11 (1> 12/7/11 lstQtr 1/19/12 2nd Qtr 6/13/12 3rd Qtr 9/12/12 4th Qtr 10/4/12 1st Qtr 2/11/13 NA <50 <5 0 <10 <10 <10 <1 0 <1 0 <1 0 <1 0 <1 0 <1 o' <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 3 24" 1 3 1 2 NA NA NA 253 236 221 221 236 347 273 259 238 519 271 524 539 177 177 391 175 427' 134 130 134 114 138 120 174 36 35 130 130' Monitor well was not installed NA 340 290 320 390 280 864 350 440 740 530 440 1,400 1,200 NA 630 390 730 2,300 380 2,200 540 340 340 1,300 210 450 400 200 121 330 10,600 NA <50 <5 0 <10 <10 <10 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <10 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 6 <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 NA NA 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 lstQtr 1/17/12 2nd Qtr 5/31/12 3rd Qtr 8/29/12 4th Qtr 10/3/12 1st Qtr 2/7/13 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA <2 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 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 <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 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 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 <01 <0 1 <0 1 <01 <01 <0 05 <0 05 NA <01 <01 <01 <0 1 <0 1 " <01 <0 1 <0 1 <0 1 <01 <0 1 <0 1 <01 <o"l <01 <01 <01 (1) VOCs were resampled because laboratory missed holding NA = not analyzed NS = not sampled Bold and red = highest concentraton since montonng started Bold and blue = lowest concentraton since montonng started Shaded indicates concentratons exceeding GWQS Bold and italics indicates the MDL exceeded the GWQS 1st Qtr = January - March 2nd Qtr = Apnl - June 3rd Qtr = July - September 4th Qtr = October - December tme TABLE 1 Historic Summary Of Monitoring Parameters Up To The 1st Quarter 2013 Chloroform Contamination Investigation DUSA White Mesa Mill Well Sampling Event Carbon Tetrachloride (5 ug/L) Chloride (mg/L) No GWQS . Parameter GWQS Chloroform (70 pg/L) Chloromethane (30 pg/L) Methylene Chloride (5M9/L) Nitrate, Nitrate + Nitrite (10 mg/L) TW4-24 2nd Qtr 6/27/07 3rd Qtr 8/15/07 4th Qtr 10/10/07 1st Qtr 3/28/08 2nd Qtr 6/25/08 3rd Qtr 9/10/08 4th Qtr 10/15/08 4th Qtr 11/18/09 1st Qtr 3/4/09 2nd Qtr 6/23/09 3rd Qtr 9/14/09 4th Qtr 12/16/09 1st Qtr 2/25/10 2nd Qtr 6/14/10 3rd Qtr 8/24/10 4th Qtr 10/15/10 1st Qtr 2/17/11 2nd Qtr 5/26/11 3rd Qtr 8/17/11 4th Qtr 11/16/11 (1)12/7/11 1st Qtr 1/16/12 2nd Qtr 6/6/12 3rd Qtr 8/30/12 4th Qtr 10/3/12 1st Qtr 2/11/13 <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 NA 770 791 692 740' 834 1180 1130 1010' 759 618 1080' 896' 639 587 522 1100' 1110 967 608 373 355 489 405 1260' NA <2 0 26 22 1 5 1 5 1 4 29 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 NA <2 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 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 NA 261 29 24 7 24 4 '453 384 44 8 30 5 304 "30 7 28 3 33 1 30 31 31 "31 35 "34 35 "37 " 37 37 38 36 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 <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 <ib <1 0 <1 0 <1 0 <1 0 NA 395 382 358 374' 344 333 366 332 328 328 371 296 306 250 312 315 321 276 294 304' 287 334 338 190' <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 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 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 <10 NA 171 29 17 18 7 221 "18~8 21 3 15 3 "153 33 142 14 4 """16 14 ~'"15 15 ""Te 16 16 16 . 17 17 9 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) 12/7/11 1st Qtr 1/18/12 2nd Qtr 6/6/12 3rd Qtr 9/11/12 4th Qtr 10/3/12 1st Qtr 2/7/13 <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 17 22 30' 15 19 26' 17' 19 19 , 19 /" 16 6 13 52 54 2 29 28 52 7 4 1 49 49 49 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 79 9 96 10 10 'll 10 'ii 12 9 12 13 TW4-27 lstQtr 1/18/12 2nd Qtr 6/13/12 3rd Qtr 9/4/12 4th Qtr 10/3/12 1st Qtr 2/7/13 <1 0 <1 0 <1 0 <1 0 <1 0 11 17 21 18 18 8 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 lstQtr 2/14/13 <10 <1 0 <1 0 <1 0 <1 0 <0 1 TW4-65 (Duplicate Sample of TW4-16) 1st Qtr 2/7/13 |<10 61 2 <1 0 |<1 0 |<1 0 <0 1 56 TW4-70 (Duplicate Sample of TW4-18) 1st Qtr 2/13/13 <1 0| 24 6 38 6 <1 0 |<1 0 NA = not analyzed NS = not sampled Shaded indicates concentratons exceeding GWQS Bold and italics indicates the MDL exceeded the GWQS 1st Qtr = January - March 2nd Qtr = Apnl - June TABLE 1 x- Historic Summary Of Monitoring Parameters Up To The 1st Quarter 2013 Chloroform Contamination Investigation DUSA White Mesa Milk Well Sampling Event Parameter GWQS Carbon Tetrachloride (5 ug/L) Chloride (mg/L) No GWQS, Chloroform (70 ug/L) Chloromethane (30 pg/L) Methylene Chloride (5 ug/L) Nitrate, Nitrate + Nitrite (10 mg/L) 3rd Qtr = July - September 4th Qtr = October - December Table 2 Summary of QA/QC Samples 1st Quarter 2013 Parameter GWQS Dup MW-16 icate of MW-16 TW4-65 RPD Dup TW4-18 icate of TW4-18 TW4-70 RPD Nitrate + Nitrite (as N) 10 mg/L O.I <0.1 #VALUE! 5.6 5.6 0.0 Chloride none 58.1 61.2 -5.2 23.1 24.6 -6.3 Chloroform 70 pg/L <1.0 <1.0 nc 34.9 38.6 -10.1 Carbon tetrachloride 5 pg/L <1.0 <1.0 nc <1.0 <1.0 nc Chloromethane 30 pg/L <1.0 <1.0 nc <1.0 <1.0 nc Methylene Chloride 5 pg/L <1.0 <1.0 nc <1.0 <1.0 nc nc = not calculated i Tabel 3 Chloroform Mass Removal Calculations DUSA White Mesa Mill, Bland, Utah 1st Quarter 2013 DRC Mass Removal Calculations Well ID MW4 MW-26 TW4-4 TW4-19 TW4-20 TW4-22 TW4-24 Ave. Chloroform (ug/L) ' Chloroform (g/L) Chloroform (Ibs/L) Chloroform (lbs/gal) Total gallons pumped 4th qtr 2012 lbs of chloroform removed Gallons of chloroform removed 1,670 1.67E-03 3.69E-06 1.40E-05 62,944 0.88 0.07 2,120 2.12E-03 4.68E-06 1.77E-05 22,651 0.40 0.03 1,460 1.46E-03 3.23E-06 1.22E-05 58,717 0.72 0.06 4,210 4.21 E-03 9.30E-06 3.52E-05 210,908 7.43 0.60 18,500 1.85E-02 4.09E-05 1.55E-04 18,177 2.81 0.23 10,600 1.06E-02 2.34E-05 8.86E-05 16,677 1.48 0.12 1 1.00E-06 2.21 E-09 8.36E-09 144,843 0.001211 0.000099 total lbs of chloroform removed 13.71 total gallons of chloroform removed 1.12