DRC-2021-012624 - 0901a06880f45dc5

•
,41.3
State of Utah
SPENCER J. COX
Governor
DEIDRE HENDERSON
Lieutenant Governor
Department of
Environmental Quality
Kimberly D. Shelley Executive Director
DIVISION OF WASTE MANAGEMENT
AND RADIATION CONTROL
Douglas J. Hansen Director
Ð RC-202( -01Z6211--
MEMORANDUM
TO: Phil Goble P /26 741
7/Z7/2-6 FROM: Dean Henderson
DATE: July 27, 2021
SUBJECT: Review of the May 10, 2021 1st Quarter, 2021 Chloroform Monitoring Report for the
Chloroform Contamination Investigation, Energy Fuels Resources (USA) Inc. ("EFRI")
White Mesa Uranium Mill ("Mill"), near Blanding, Utah.
The Utah Division of Waste Management and Radiation Control ("Division") has reviewed the May 10,
2021 1st Quarter, 2021 Chloroform Monitoring Report ("Report") for the Chloroform Contamination
Investigation. For the review of this report the following regulatory enforcement documents were used:
• EFRI issued Ground Water Quality Discharge Permit No. UGW370004 ("Permit"). Permit
version that was signed on March 19, 2019.
• The EFRI Quality Assurance Plan ("QAP") September 10, 2019 (Revision. 7.6)
• The EFRI Groundwater Corrective Action Plan ("GCAP") September 14, 2015 (Revision 0)
• Utah Stipulation and Consent Order Docket Number UGW20-01, September 16, 2015.
REVIEW
GCAP Part III.0 requires the 1st Quarter Report to be submitted to the Division on or before June 1, of
each year. The Report was received by the Division on May 12, 2021 (date of Report
May 10, 2021) which meets the GCAP requirement.
Monitor Well Sampling
The following 42 monitor wells were sampled as required in the GCAP (see Table 1 below):
MW-4 TW4-3 TW4-8 TW4-13 TW4-21 TW4-26 TW4-31 TW4-36 TW4-41
MW-26 TW4-4 TW4-9 TW4-14 TW4-22 TW4-27 TW4-32 TW4-37 TW4-42
MW-32 TW4-5 TW4-10 TW4-16 TW4-23 TW4-28 TW4-33 TW4-38
TW4-1 TW4-6 TW4-11 TW4-18 TW4-24 TW4-29 TW4-34 TW4-39
TW4-2 TW4-7 TW4-12 TW4-19 TW4-25 TW4-30 TW4-35 TW4-40
DRC-20 195 North 1950 West • Salt Lake City, UT
Mailing Address: P.O. Box 144880 • Salt Lake City, UT 84114-4880
Telephone [phone] • Fax [phone] • T.D.D. [phone]
www.deq.utah.gov
Printed on 100% recycled paper
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The water samples for the above wells were analyzed for the following constituents as required in the
QAP:
Chloroform Chloride
Chloromethane Methylene chloride
Carbon tetrachloride Nitrate + Nitrite as Nitrogen.
The analytical methods used is consistent with the requirements of the GCAP. For a summary of the 1st
Quarter, 2021 and historic analytical results see Table 1 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 monitoring wells.
• Existing monitoring well MW-4 and all of the temporary chloroform investigation wells.
• Piezometers P-1, P-2, P-3A, 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 pumping wells
MW-4, MW-26, TW4-1, TW4-2, TW4-4, TW4-11, TW4-19, TW4-21, TW4-22, TW4-24, TW4-25,
TW4-37, TW4-39, TW4-40, TW4-41, TW4-42, and TWN-2.
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, TW4-32, and TW4-38.
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, TW4-36, and TW4-42.
3. The pumping wells are continuously pumped on a set schedule and are sufficiently purged to
collect a sample
Pumping Wells: MW-4, MW-26, TW4-1, TW4-2, TW4-4, TW4-11, TW4-19,
TW4-21, TW4-22, TW4-24, TW4-25, TW4-37, TW4-39, TW4-40, and TW4-41.
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Holding Times
The water samples method holding times for each parameter for samples collected at each monitor well
were received and analyzed within the required holding times stated in the QAP.
Receipt Temperature
Water samples were received within the required QAP temperature limit of 6° C.
Analytical Methods
The analytical methods reported to be use by the laboratory to analyze Chloroform, Chloride,
Chloromethane, Methylene chloride, Carbon tetrachloride, and Nitrate + Nitrite as Nitrogen are
incompliance with analytical methods required in the Chloroform QAP.
Detection Limits
Analyses 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.
EFR Duplicate Sample Comparison
Three duplicate samples were collected. Monitor well TW4-3 and its duplicate sample TW4-65, and
TW4-9 and its duplicate sample TW4-70; and MW-32 and its duplicate sample TW4-75. All analytical
results for the three sample/duplicate pairs were within the 20% relative percent difference (RPD)
acceptance limits (see Table 2 below).
Mass Removed and Plume Residual Mass
Chloroform removal was first estimated from the 1st Quarter, 2007. Since that estimation the mass
removed by each pumping well for each quarter has been calculated. Estimated reported mass removed
during the 1st Quarter 2021 is 16.8 lbs. (see Table 3 below) which is greater than the estimated 9.6 lbs.
removed in the 4th Quarter 2020. The greater mass removal is a primarily due to increase in
concentrations in TW4-19 and TW4-39.
Using the "Chloroform Plume Mass Calculation Method" as described in Appendix A of the GCAP the
residual mass of chloroform within the plume is estimated as 1,273 lbs. in the 1st Quarter, 2021. This
approximately 558 lbs. larger than the 4th Quarter 2020 estimated mass of 715 lbs.
As per Part III.B.2 of the GCAP, the electronic files were used in 1st Quarter, 2021 to calculate the mass
estimates. The following files were used to calculate the estimated chloroform mass within the
chloroform plume:
• Excel spreadsheet that included: well name; well location (easting and northing); Laboratory
reported concentration in j.tg/1 in the 1st Quarter, 2020 and corresponding log equivalent values.
• Surfero griding parameters: kriging parameters: SURFERTM default parameters (point kriging,
linear variogram, slope = 1, no anisotropy [anisotropy = 1], no search constraints; min x, max x
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(UTME[m]): 631900, 633043; min y, max y (UTME[m]): 4154240, 4155550.64; grid spacing in
x, y (m): 15.24, 15.24
• Surfer chloroform concentration grid file.
• Concentration GE 70 Grid file
• Intermediate Surfer Grid Files: water level grid; aquifer base grid; saturated thickness grid
Based on the review of these files it appears that the date entered and generated is appropriate to
calculate an estimated chloroform mass within the chloroform plume and EFRI followed Part III.B.2 and
Appendix A of the GCAP.
Reporting
The Report included the following information as required in the QAP:
a) Introduction
b) Sampling and Monitoring Plan
-Description of monitor wells
-Description of sampling methodology, equipment and decontamination procedures
-Identify all quality assurance samples, e.g. trip blanks, equipment blanks,
duplicate samples
c) Data Interpretation
-Interpretation of groundwater levels, gradients, and flow directions.
Interpretations will include a discussion on: 1) A current site groundwater
contour map, 2) hydrographs to show groundwater elevation in each
monitor well over time, 3) depth to groundwater measured and
groundwater elevation from each monitor well summarized in a data table,
that includes historic groundwater level data for each well, and 4) an
evaluation of the effectiveness of hydraulic capture of all contaminants of
concern.
-Interpretation of all analytical results for each well, including a discussion
On: 1) a current chloroform isoconcentration map with one of the
Isoconcentration lines showing the 70 lig/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, 5) estimated residual mass of chloroform within the
plume.
d) Conclusions and Recommendations
e) Electronic copy of all laboratory results for Chloroform Investigation monitoring conducted
during the quarter.
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f) Copies of DUSA field records, laboratory reports and chain of custody forms.
Evaluation of the Chloroform Contaminate Plume and Its Associated Contaminants
Bounding Chloroform Plume
Groundwater monitoring data up to the 1st Quarter, 2021 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
compliance monitoring wells that have a chloroform concentration of <70 µg/L ("GWQS = 70 µg/L)
with the exception of TW4-24 (96.2µg/L) and TW4-30 (74.8 µg/L). Both these well have exceeded the
chloroform GWQS for the second consecutive quarterly monitoring event (4th quarter 2020 and 1st
quarter 2021). Therefore, EFRI will be required to follow the chloroform GCAP Part II.H.
On July 29, 2021, the Division has scheduled a conference call with EFRI to discuss a plan and time
schedule to bound the plume in the vicinity of well TW4-24.
On July 7, 2021 EFRI submitted to the Division a Plan and Time Schedule ("Plan"), Pursuant to Part
II.H.2 of the GCAP for the proposed new well TW4-43 located approximately 200 feet down gradient of
TW4-30. On July 21, 2021 the Division sent a letter to EFRI approving the Plan.
Performance Monitor Wells ("PM") (Wells Exceeding Chloroform Concentrations GWQS of 701Ag/L1
Six (6) PM wells still exceed 70 µg/L: TW4-7, TW4-10, TW4-16, TW4-26, TW4-29, and TW4-30.
Compliance Monitor Wells ("CM") rWells with Chloroform Concentrations between < 1 and 70µg/L1
Eight (8) CM wells range with detectable chloroform concentration but still below 70µg/L: TW4-5,
TW4-6, TW4-8, TW4-9, TW4-14, TW4-18, TW4-27 and TW4-30.
CM Wells Below the Laboratory Chloroform Detection Limit (<1.0 µg/L)
Thirteen (13) CM wells were below the laboratory detection limit for chloroform (<1.0 µg/L): MW-32,
TW4-3, TW4-12, TW4-13, TW4-23, TW4-28, TW4-31, TW4-32, TW4-34, TW4-35, TW4-36, TW4-
38, and TW4-42.
Pumping Wells
There are 15 pumping wells in full operation in the 1ST Quarter, 2021, 14 pumping wells MW-4, MW-
26, TW4-1, TW4-2, TW4-4, TW4-11, TW4-19, TW4-21 TW4-22, TW4-24, TW4-37, TW4-39, TW4-
40, and TW4-41 exceed chloroform concentrations of 70 µg/L. Pumping well TW4-25 had a non-
detectable (<1.0 µg/L) chloroform concentration (see table 1 below).
Nitrate, Nitrate + Nitrite ("nitrate") Concentrations
Pumping wells TW4-22 (69.6 mg/L) and TW4-24 (41.9 mg/L) exceed the nitrate GWQS of 10 mg/L.
These nitrate exceedances 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 ("NCAP"), approved on December 12, 2012.
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Well TW4-26 (11.3 mg/1) continue to exceed the nitrate GWQS of 10 mg/l. The source of nitrate may
be from the chloroform source plume. Pumping well TW4-40 located approximately 200 feet down
gradient of TW4-26 and should remove and prevented further elevated nitrate concentrations migrating
downgradient in this vicinity. In addition, nitrate concentrations at TW4-40 are currently at 2.43 mg/l.
Therefore, at this time no action is recommended. However, should future nitrate concentrations in
TW4-40 increases to above 10 mg/1 an additional investigation may be recommended.
Well TW4-27 (23.0 mg/L) continue to exceed the nitrate GWQS of 10 mg/l. The source of nitrate may
be from the chloroform source plume. Wells TW4-29, TW4-30, and TW4-31 located approximately
200 feet down and/or cross gradient of TW4-27 have nitrate concentrations in the 1st quarter 2021
below the nitrate GWQS of 3.09 mg/L, 3.54 mg/L, and 0.501 mg/L respectively. Therefore, at this time
no action is recommended. However, should future nitrate concentrations in these three down and/or
cross gradient wells increases to above 10 mg/L or shows an increasing trend an additional investigation
may be recommended.
Conclusions on Compliance with the Permit and QAP
Per the Division review it appears that the Report complies with Permit, QAP, and GCAP. Therefore, a
letter will be drafted notifying EFR of the review and closing out of for the 1st Quarter, 2021
Chloroform Monitoring Report for the chloroform contamination investigation.
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References
EFRI, State of Utah Stipulated and Consent Order ("SCO") Docket Number UGW-20-01 White
Mesa Mill — Energy Fuels Resources (USA) Inc. ("EFRI") Plan and Time Schedule, Revision 1,
Pursuant to Part 11.112 of the Groundwater Corrective Action Plan ("GCAP") included as
Attachment 1 to the SCO, January 10, 2018.
EFRI Quality Assurance Plan ("QAP") June 23, 2018 (Revision. 7.4)
EFRI issued Ground Water Quality Discharge Permit No. UGW370004. Permit version that was
signed on March 19, 2019.
EFRI, White Mesa Uranium Mill, Notice of Violation and Corrective Action Order UDEQ
Docket No. UGW-20-01 Notice Pursuant to the Chloroform Pumping well Operations and
Maintenance plan, Letter August 5, 2020. (DRC-2020-013810)
EFRI, White Mesa Uranium Mill Chloroform Monitoring Report 4th (October through
December) Quarter 2020, February 22. 2021 (DRC-2021-002766)
EFRI, White Mesa Uranium Mill Chloroform Monitoring Report 1st (January through March)
Quarter 2021, May 10, 2021. (DRC-2020-018798)
EFRI, Stipulation and Consent Order ("SCO") Docket Number UGW-20-01 White Mesa Mill —
Energy Fuels Resources (USA) Inc. ("EFRI") Plan and Time Schedule ("Plan"), Pursuant to Part
II.H.2 of the Groundwater Corrective Action Plan ("GCAP")included as Attachment 1 to the
SCO, July 7, 2021.
Utah DEQ QWMRC, July 7, 2021, Stipulation and Consent Order Docket Number UGW-20-01
White Mesa Mill — Energy Fuels Resources (USA) Inc. Plan and Time Schedule ("Plan"),
Pursuant to Part II.H.2 of the Groundwater Corrective Action Plan included as Attachment 1 to
the SCO. Approval, July 21, 2021. (DRC-2021-009822)
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THIS PAGE WAS INTENTIONALLY LEFT BLANK
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Tables 1 through 4
TABLE 1 (1 of 31)
Historic Summary Of Monitoring Well Analytical Results Up To The 1st Qarter 2021
Chloroform Contamination Investigation DUSA White Mesa Mill
MW4I. (chloratorrn purnping vnedl Mailed pumping 3/4/03) Sampling Event
Parameter
(GWQS)
Carbon Tetrachloride (5 pg/L) Chloroform (70 pg/L)
Chloromethane
(30 pgIL)
Methylene Chloride
(5 pg/L)
Chloride
No GWQS (mg/L)
Nitrate, Nitrate . Nitrite
(10 mg/L)
1st Qtr 3/16/2005 NA 2,900 NA NA NA 6.3
2nd Qtr 5/25/2005 NA 3,170 NA NA NA 7.1
3rd Qtr 8/31/2005 <10 3,500 <10 <10 NA 7.0
4th Qtr 12/7/2005 <50 3.,000 <50 450 53 7.0 ....... 1st Qtr 3/9/2006 <50 .3, foo <50 <50 ....49 6.0
2nd Qtr 6/14/2006 <50 . . 3,000 <50 <50 49 6.0
3rd Qtr 7/20/2006 <50 2,820 <50 <50 48 1.2
4th Qtr 11/8/2006 2.1 2 830 1.4 <1.0 50 .:!.! 1st Qtr 2/28/2007 1.6 2,300 <1.0 <1.0 47 6.3
2nd Qtr 6/27/2007 1.8 2,000 <1.0 <1.0 45 7.0
3rd Qtr 8/15/2007 1.9 2,600 <1.0 <1.0 47 6.2
4th Qtr 10/10/2007 1.7 1300 01.0 01.0 45 6.2 1st Qtr 3/28/2008 1.7 2,40-0 <1.0 <1.0 42 5.8
2nd Qtr 6/25/2008 1.8 2,500 <1.0 <1.0 42 6.1
3rd Qtr 9/10/2008 1.8 1,800 <1.0 <1.0 35 6.4
4th Qtr 10/15/2008 1.7 .L.1.PP '1.0 <1.0 ............... ...4.5. 5.9 lst Qtr 3/4/2009 1.5 2,200 <1.0 <1.0 37 5.7
2nd Qtr 6/23/2009 1.3 1,800 <1.0 <1.0 34 5.2
3rd Qtr 9/14/2009 1.4 2,000 <1.0 <1.0 43 5.3 411.1pk_. _ _12/14/4099 . _.15 1 800 01.0 <1.0 44 5.8 ........ 1st Qtr 2:/17/2010 1.2 <1.0 <1.0 45 4.0 1,600 2nd Qtr 6/14/2010 1.2 2,100 <1.0 <1.0 41 5.1 3rd Qtr 8/6/2010 , 1.5 1,900 <1.0 <1.0 38 4.8
4th Qtr 10/15/2010 1.4 1520 01.0 01.0 41 4,.. 1st Qtr 2/23/2011 1.5 1,700 <1.0 <1.0 40 .4.6
2nd Qtr 6/1/2011 1.4 1,700 <1.0 <1.0 35 4.9
3rd Qtr 8/17/2011 1.1 1,700 <1.0 <1.0 41 4.9
4th Qtr 1/16/2011 1.3 1 600 <1 0 <1.0 40 5.1 fift)rIT(- iiiiitii. ----- ' 1 1,500 <1.0 41.0 4.8
2nd Car 6/6/2012
3rd Qtr 9/4/2012
1.2 1.5 1,400 1,500 <1.0 <1.0 ° il < ..: 39.0 41.0
_ 9s 4. 5.0
10/4/2012 1 1 300 <1.0 < 0 41.0 4.8 41 tsht QQ,,tr 2/11/2013 1.48 1,670 <1.0 <1.0 37.8 4.78
2nd Qtr 6/5/2013 1.31 1,490 <1.0 <1.0 44.0 4.22
3rd Qtr 9/3/2013 1.13 1,520 <1.0 <1.0 41.4 4.89
4th Qtr 10/29/2013 5.58 1 410 <1.0 <1.0 40.1 ..,.?. lst Qtr 1/27/2014 4.15 1,390 <1.0 <1.0 38.5 41
2nd Qtr 5/19/2014 5.21 1,390 <1.0 <1.0 39.9 4.08
3rd Qtr 8/11/2014 7.6 1,490 <1.0 <1.0 41.0 3.7
4th Qtr 10/21/2014 <1.0 1,440 <1.0 <1.0 41.5 5.07
1st Qtr (2) 3/9/2015 1.26 1,400 <1.0 <1.0 40.7 . 5.75
2n1 Qtr 6/8/2015 <1.0 1,300 <1.0 <1.0 43.1 2.53
3rd Qtr 8/31/2015 <1.0 1,200 1.42 <1.0 44.3 4.79
4t0 Qtr 10/19/2015 <1.0 .1200 <1.0 <1.0 40.8 4P .:!. 1st Qtr • 3/9/2016 <1.0 1,240 <1.0 01.0 42.2 -5.15
2nd Qtr 5/23/2016 1.44 1,580 <1.0 <1.0 43.7 4.54
3rd Qtr 7/25/2016 <1.0 1,430 <1.0 <1.0 42.5 4.95 4th Qtr 10/12/2016 1.24 1..‘47.0 <1.0 <1.0 44.8 A.P.§. 1st Qtr 3/8/2017 1.22 1,450 <1.0 <1.0 43.3 4.60
2nd Qtr 6/13/2017 1.15 1,430 <1.0 <1.0 44.0 4.88
3rd Qtr 7/26/2017 1.15 1,400 <1.0 <1.0 43.8 4.59
4th Qtr 10/11/2017 <1.0 1,320 <1.0 <1.0 43.8 5.25
DWMRC spgAmple <19 1 400 <30 70 J 43.0 .4.1.. 1st Qtr 1.07 1,320 <1.0 <1.0 46.2 4.47
2nd Qtr 6/8/2018 <1.0 1,240 <1.0 <1.0 4.5 4.64
3rd Qtr 8/22/2018 <1.0 1,300 <1.0 <1.0 46.5 4.55
th Qtr 11/28/2018 <1.0 1,330 <1.0 <1.0 43.1 444
1st Qtr 3/8/2019 <1.0 1,190 <1.0 01.0 41_5 5.05
nd Qtr 6/5/2019 <1.0 1,300 <1.0 <1.0 40.6 5.16
3rd Qtr 9/4/2019 <1.0 1,180 <1.0 <1.0 , 41.9 4.69
1,17.0 1,230 <1.0 <1.0 <1.0 <1.0
45.5
48.1
4.34
6.22 4th Qtr 122/1109/22002190 1st Qtr <2..00
2nd Qtr 5/27/2020 <1.0 1,250 <1.0 <1.0 40.7 5.04
3rd Qtr 9/4/2020 <1.0 1,240 <1.0 <1.0 43.8 4.93
th Qtr 10/18/2020 <1.0 1 050 <1 0 <1.0 41.4 4.62
st Qtr 2/23/2021 <1.0 1,150 <1.0 <1.0 46.5 4.61
MW-4.A.OW47.A1
st Qtr 3/16/2.005 NA 3,700 NA NA NA 7.1
2nd Qtr 5/25/2005 NA 3,740 NA NA NA 7.8
3rd Qtr 8/31/2005 <10 3,800 <10 <10 NA 6.9
th Qtr 12/7/2005 <50 3 000 <50 <50 55 6.7
st Qtr 3/9/2006 <50 3,700 <50 <50 53
2nd Qtr 6/14/2006 <50 3,300 <50 <50 54 7.3
3rd Qtr 7/20/2006 <50 3,190 <50 <50 54 1.2
th Qtr 11/8/2006 2.4 3,370 <1.0 <1.0 54 7.1
1st Qtr 2/28/2007 1.9 2,500 <1.0 <1.0 60 7.1 Well abandonded
) As of March 2012 both north and south wild life ponds ro
(2) chloroform pumping wells TtA/4-1. 1W4-2, and TW4-11 started in 1/14/15
NA = not analyzed Shaded indicates concentrations exceeding GWOS. Bold and italics indicates tile MDL exceeded the GWQS. J ApproArnated 19100
TABLE 1 (2 of 31)
Historic Summary Of Monitoring Well Analytical Results Up To The 1st garter 2021 Chloroform Contamination Investigation
DUSA White Mesa Mill
MW-26 (ro.e, rm-15)..raonr, purnping well started 8/8/03
Sampling Event
Parameter
(GWQS) Carbon Tetrachlonde (5 pg/L) Chloroform (70 pg/L) Chloromethane
(30 pg/L)
Methylene Chloride
(5 pg/L) Chloride No GWQS (mg/L) Nitrate, Nitrate + Nitrite (10 mg/L) 1st Qtr 3/16/2005 NA 310 NA NA NA 0.3 2nd Qtr 5/25/2005 NA 442 NA NA NA 0.2 3rd Qtr 8/31/2005 <5.0 960 5.4 05.0 NA 0.2 4th Qtr 1st Qtr 12/7/2005
3/9/2006
<50
<50
14000 .1,160
<50 <so <50
<50 . 55
52 ................... 0.3
6... 2nd Qtr 6/14/2006 <50 830 <50 <50 52 0.2 3rd Qtr 7/20/2006 <50 2,170 <50 <50 65 1.4 4th Qtr 11/8/2006 <1.0 282 <1.0 2.6 54 0.3 1st qtr 2/28/2007 <1.0 ,570 <1.0 5.5 56 6.6 2nd Qtr 6/27/2007 <1.0 300 <1.0 13 49 0.4 3rd Qtr 8/15/2007 <1.0 1,400 <1.0 36 57 1 41h Qtr 10/10/2007 <1.0 lgoo <1.0 14 57 0.6 1st Qtr 3/28/2008 <1.0 9.30 <1.0 40 49 0.1 2nd Qtr 6/25/2008 <1.0 1,300 <1.0 53 57 0.6 3rd Qtr 9/10/2008 <1.0 , 630 <1.0 24 44 0.2 4th Qtr 10/15/2008 NA NA NA NA 64 0.1 11/18/2008 <2.0 1 700 <2.0 100 NA NA 1st Qtr 3/4/2009 <1.0 950 <1.0 51 49 0.4 2nd Qtr 6/23/2009 <1.0 410 <1.0 12 46 0.2 3rd Qtr 9/14/2009 <1.0 850 <1.0 30 46 0.1 4th Qtr 12/14/2009 <1.0 1.,100 <1.0 40 60 2.3 1st Qtr 2/17/2010 <1.0 730 <1.0 19 57 0.2 2nd Qtr 6/14/2010 1.2 1,600 <1.0 <1.0 40 6.8 3rd Qtr 8/16/2010 <1.0 2,200 <1.0 21 49 0.6 4th Qtr 10/15/2010 <1.0 976 <1.0 6.5 65 0,7 1st Qtr <1.0 450 <1.0 3.8 57 . 6.5 2nd Qtr 5/31/2011 <1.0. 1,800 <1.0 1.3 88 0.4 3rd Qtr 8/17/2011 <1.0 . „ 720 <1.0 7.2 58 , 0.9 41h Qtr 11/16/2011 NA NA NA NA 69 2.0
SR <1 0 1,800 <1.0 2.9 NA NA 1st Qtr (2) 2/27/2012 <1.0 1400 <1.0 16 98 1.7 2nd Qtr 6/6/2012 <1.0 3,000 „ <1.0 21 73 2.5 3rd Qtr . 9/4/2012 <1 3,100 <1 31 73 2.6 4th Qtr 16/4/2012 <1 1,200 <1 4 68 1.8 1st Qtr 2/11/2013 <1 2,120 <1 9.34 .81.4 2.27 2nd citr 6/5/2013 <1.0 . 4,030 <1.0 52.4 77.9 2.11 3rd Qtr 9/3/2013 <1.0 , , 2,940 <1.0 33.2 60.5 1.18 4th Qtr 10/29/2013 <1.0
1:1 .0 4.03 72.3 1.38 1st at 1/27/2014 <1.0 .11100 118 594 0.55 2nd Qtr 5/19/2014 <1.0 1,960 <1.0 15.4 53.4 0.93 3rd Qtr 8/11/2014 <1.0 2,120 8.7 26 59 0.7 41h Qtr 10/21/2014 <1.0 1090 <1.0 23.2 60.1 0.93 1st Qtr 3/9/2015 <1.0 1,980 <1.0 27.4 56.5 0.73 2nd Qtr' (3) 6/8/2015 <1.0 1,980 <1.0 11.2 62 0 42
3rd Qtr 8/31/2015 <1.0 , 2,350 4.05 11.6 69.6 0.68 '4th Qtr 10/19/2015 <1 0 2 680 . 1.32 8.28 62.6 0.991
.1st Qtr 3/9/2016 <1.0 2650 <1.0 4.66 68.3 1.45 2nd Qtr 5/23/2016 <1.0 2,220 <1.0 4.57 66.2 1.12 3rd Qtr 7/25/2016 <1.0 illitri <1.0 7.81 66.4 1.57 41h Qtr (4) 10/12/2016 <1.0 2,510 <1.0 4.31 66.2 1.18 1st Qtr 3/8/2017 <1.0 1 290 <1.0 7.65 58.4 0.768 „„. 2nd Qtr 6/13/2017 <1.0 2,450 <1.0 7.59 64.3 0.922 3rd Qtr 7/26/2017 <1.0 1,230 <1.0 5.26 61.4 1.56 4th Qtr 16/11/2617 <1.0 2,570 <1 0 7.83 62.2 1.18 1st Qtr , 3/12/2018 <1.0 1,210 <1.0 2.14 60.3 1.57 2nd dtr 6/8/2018 <1.0 , 1,870 <1.0 9.19 58.7 , 0.901 3rd Qtr 8/22/2018 <1.0 1,680 <1.0 <1.0 91.4 2.80 4th Qtr 11/28/2018 <1.0 1.,4.80 <1.0 <1.0 85.5 1.86 1st Qtr 3/8/2019 1,110 <1.0 2.2 69.9 1.88 . 2nd Qtr 6/5/2019 <1.0 1,280 <1.0 1.19 80.7 2.83 3rd Qtr 9/4/2019 <1.0 1,680 <1.0 1.93 76.2 3.08 4th Qtr 12/10/2019 <1.0 1.360 <1.0 1.78 83.2 0.977 1st Qtr 2/19/2020 <1.0 1,100 <1.0 <1.0 88.9 1.17 2nd Qtr 6/12/2020 <1.0 1,140 <1.0 <1.0 35.1 2.93 3rd Qtr 9/4/2020 <1.0 1,130 <1.0 2.57 70 0.42 41h Qtr 10/28/2020 <1.0 866 <1.0 <1.0 37.4 3.62 1st Qtr 2/23/2021 <1.0 3 060 <1.0 3 46 59 5 0.349 (1) VOCs were resampled because laboratory missed holding Orne. (2) As of March 2012 both north and south wild life ponds no lonor renew-29 water
21.2111m/0m purl:into/ell 1W4-37-sta0ed in 6/9/15
(4) chloroform pullyinUellS TW4-1, TW4-2. and TW4-11 started in 1/14/15 NA = not analyzed Shaded indicates concentrations exceeding GWQS. Bold and italics indicates the MDL exceeded the GWQS.
TABLE 1 (3 of 31)
Histonc Summary Of Monitoring Well Analytical Results Up To The 1st Qarter 2021 Chloroform Contamination investigation
DUSA White Mesa Mill
MW-32 (former rw4-17)
Sampling Event
Parameter
(GWQS) Carbon Tetrachloride
(§_pg/L)
Chloroform
(70 pg/L)
Chloromethane
(30 pg/L) ._.
Methylene Chloride
(5 po/L) Chlonde No GWQS (mg/L) Nitrate, Nitrate + Nitrite (10 mg/L) 1st Qtr 3/16/2005 NA <1 0 NA NA NA <0 1 2nd Qtr 5/25/2005 NA <1 0 NA NA NA <0 1 3rd Qtr 8/31/2005 <1 0 <1 0 3 2 <1 0 NA <0 1 4th Qtr 12/7/2005 <1 0 <1 0 <1 0 <1 0 33 <0 1 l if Qtr 3/9/2006 <1 0 •<1 0 <1 0 <1 0 . 32 <0 1 2nd Qtr 6/14/2006 <1 0 <1 0 3 5 <1 0 30 <0 1 3rd Qtr 7/20/2006 <1 0 <1 0 1 8 <1 0 32 <1 0 4th Qtr .11/8/2006 <1 0 •<1 0 1 5 <1 0 31 < 1 1st Qtr 2/28%2007 <1 0 <1 0 <1 0 <1 b 32 <1 0 2nd Qtr 6/27/2007 <1 0 <1 0 <1 0 <1 0 32 <1 0 3rd Qtr 8/15/2007 <1 0 <1 0 <1 0 <1 0 31 <1 0 41h Qtr 10/10/2007 <1 0 • <1 0 <1 0 . <1 0 32 • <1 0 1st Qtr 3/28/2008 <1 0 <1 0 <1 0 <1 0 31 < 1 2nd Qtr 6/25/2008 <1 0 <1 0 <1 0 <1 0 29 <1 0 3rd Qtr 9/10/2008 <1 0 <1 0 <1 0 <1 0 30 <1 0 4th Qtr 10/15/2008 <1 0 <1,0 <1 0 <1 0 26 <0 05 1st Qtr 3/4/2009 <1 0 •<1 0 <1 0 • <1 0 • 30 < 1 2nd Qtr 6/23/2009 <1 0 <1 0 <1 0 <1 0 31 <0 1 3rd Qtr 9/14/2009 <1 0 <1 0 <1 0 <1 0 33 <0 1 4th Qtr 12/16/2009 <1 0 • <1 0 <1 0 <1 0 35 • 1 .<0 l sf Qtr 2/17/2010 <1 0 <1 0 <1 0 <1 0 38 <0 1 2nd Qtr 6/14/2010 <1 0 <1 0 <1 0 <1 0 32 <0 1 3rd Qtr 8/16/2010 <1 0 <1 0 <1 0 <1 0 28 <0 1 4th Qtr 10/15/2010 <1 0 •<1 0 • <1 0 <1 0 24 • <0 1 1st Qtr 2/23/2011 <1 0 <1 0 <1 0 <1 0 40 <0 1 2nd Qtr 5/25/2011 <1 0 <1 0 <1 0 <1 0 31 <0 1 3rd Qtr 8/18/2011 <1 0 <1 0 <1 0 <1 0 33 <0 1 4th Qtr 11/16/2011 NA NA NA NA 32 <0 1
) Q 12/7/2011 1sttr (V) 1/18/2012 <1 0 <1 0 •<1 <1 0 0 <1 0 - <1 0 <1 0 <1 0 NA
21
NA
<0 1 . 2nd QV 6/22/2012 <1 0 <1 0 <1 0 <1 0 32 -<0 1 3rd Qtr 9/5/2012 <1 0 <1 0 <1 0 <1 0 33 <0 1 41h Qtr - _ 10/10/2012 <1 0 • <1 0 <1 0 • <1 0 _ 35 <0 1 -2/1122013 1st Qtr <1 0 <1 0 <1 0 <1 0 34 3 <0 1 2nd Qtr 6/18/2013 <1 0 <1 0 <1 0 <1 0 34 9 <0 1 3rd Qtr 9/3/2013 <1 0 <1 0 <1 0 <1 0 33 <0 1 4th Qtr 10/29/2013 <1 0 <1 0_ <1 0 <1 0 35 7 <0 1 1st Qtr 1/29/2014 <1 0 •<1 0 <1 0 <1 0 34 <0 1 2nd Qtr 5/23/2014 <1 0 <1 0 <1 0 <1 0 39 7 <0 1 3rd Qtr 8/26/2014 <1 0 <1 0 <1 0 <1 0 34 <0 1 .41h Qtr 10/29/2014 <1 0 <1 0 <1 0 <1 0 • 34 9 <0 1 1st Qtr 3/17/2015 <1 0 <1 0 <1 0 <1 0 36 3 <0 1 2nd Qtr 6/11/2015 <1 0 <1 0 <1 0 <1 0 35 8 <0 1 3rd Qtr 9/9/2015 <1 0 <1 0 <1 0 <1 0 37 7 <0 1 4th Qtr 10/28/2015 <1 0 <1 0 <1 0 <1 0 34 7 _._ <0 1 1st Qtr 3/22/2016 <1 0 <1 0 <1 0 <1 0 36 7 <0 1 Duplicate TW4-70 <1 0 <1 0 <1 0 <1 0 37 7 0 119 2nd Qtr 6/8/2016 <1 0 <1 0 <1 0 <1 0 36 4 <0 1 Duplicate TW4-70 <1 0 <1 0 <1 0 <1 0 37 7 <0 1 3rd Qtr 8/19/2016 <1 0 <1 0 <1 0 <1 0 35 7 <0 1 4th Qtr 10/31/2016 <1 0 • <1 0 <1 0 <1 0 36 9 <0 1
1st Qtr 3/21/2017 <1 0 <1 0 -.41 0 <1 0 33 7 <0 1 2nd Qtr 6/21/2017 <1 0 <1 0 <1 0 <1 0 37 2 <0 1 3rd Qtr 8/8/2017 <1 0 <1 0 <1 0 <1 0 38 1 <0 1 4th Qtr 10/12/2017 <1 0 <1 0 <1 0 <1 0 32 6 <0 1 1st Qtr 3/15/2018. <1* 0 •<1 0 <1 0 <1 0 39 4 <0 1 Duplicate TW4-70 <1 0 <1 0 <1 0 <1 0 39 3 <0 1 2nd Qtr 6/14/2018 <1 0 <1 0 <1 0 <1 0 34 4 <0 1 3rd Qtr 9/22/2018 <1 0 <1 0 <1 0 <1 0 41 2 <0 1 4th Qtr 10/29/2018 <1 0 <1 0 <1 0 <1 0 32 9 • <0 1 1st Qtr 3/19/2019 <1 0 <1 0 <1 0 <1 0 35 3 <0 1 2nd Qtr 6/18/2019 <1 0 <1 0 <1 0 <1 0 36 5 <0 1 3rd Qtr 9/11/2019 <1 0 <1 0 <1 0 <1 0 41 2 <0 1 4th Qtr 12/18/2019 <1 0 <1 0 <1 0 <1 0 36 3 <0 1 1st Qtr 3/18/2020 <1 0 •<1 0 <1 0 <1 0 36 <0 1 Duplicate TW4-75 <1 0 <1 0 <1 0 <1 0 34 8 <0 1 2nd Qtr 6/12/2020 <1 0 <1 0 <1 0 <1 0 35 6 <0 1 3rd Qtr 9/18/2020 <1 0 <1 0 <1 0 <1 0 34 7 <0 1 4th Qtr 11/4/2020 <1 0 <1 0 <1 0 <1 0 31 3 <0 1 Duplicate TW4-65 <1 0 <1 0 <1 0 <1 0 35 9 • <0 1 1st Qtr 3/18/20-20 <1 0 <1 0 <1 0 <1 0 36 8 <0 1 Duplicate TW4-75 <1 0 <1 0 <1 0 <1 0 37 4 <0 1
(1) VOCs were resembled because laboratory missed holding time (2) As of March 2012 both north and south wild hfe ponds no longer receiving wat r NA = not analyzed Shaded indicates concentrations exceeding GWQS
TABLE 1 (4 of 31) Historic Summary Of Monitoring Well Analytical Results Up To The 1st Qarter 2021
Chloroform Contamination Investigation
DUSA White Mesa Mill
TW4-1(.1oreform pumping well Marred m 1/14/15)
Sampling Event Parameter
(GWQS) Carbon Tetrachloride
(5 pgIL)
Chloroform
(70 pg/L)
Chloromethane
(30 pg/L)
Methylene Chloride
(5 pg/L)
Chloride
No GWQS (mg/L) Nitrate, Nitrate -.- Nitrite
(10 mg/L) lst Qtr 3/16/2005 NA 2,700 NA NA NA 9.1 2nd Qtr 5/25/2005 NA 3,080 NA NA NA 10.6 3rd Qtr 8/31/2005 <10 2,900 <10 <10 NA 9.8 41h Qtr 12/7/2005 <50 2,400 <50 <50 52 9.7 1st Qtr 3/9/2006 <50 2,700 <50 <50 49 9.4 2nd Qtr 6/14/2006 <50 2,200 <50 <50 48 9.6 3rd Qtr 7/20/2006 <50 2,840 <50 <50 51 4th Qtr 11/8/2006 1.4 2,260 01.0 <1.0 47 9.2 1st Qtr 2/28/2007 1.2 1,960 <1.0 <1.0 47 8.9 25d Qtr 6/27/2007 1.4 1,900 <1.0 <1.0 45 9 3rd Qtr 8/15/2007 1.3 2,300 <1.0 <1.0 43 8.4 41h Qtr 10/10/2007 1.3 2 000 <1.0 <1.0 43 7.8 1st Qtr 1.3 2,000 <1.0 <1.0 39 7.6 2nd Qtr 6/25/2008 1.1 1900, <1.0 <1.0 39 8.68 '3rd Qtr 9/10/2008 1.3 1,700 <1.0 <1.0 35 8.15 41h Qtr 10/15/2008 1.3 1,700 <1.0 <1.0 41 9.3 lst Qtr 3/11/2009 1.1 1,760 <1.0 <1.0 37 7.5 2nd Qtr 6/23/2009 1 1,500 <1.0 <1.0 37 6.9 3rd Qtr 9/14/2009 <1.0 1,700 <1.0 <1.0 36 7.3 41h Qtr 12/29/2009 <1.0 .1,460 <1.0 <1.0 41 6.8 1st Qtr 3/3/2010 <1.0 1,360 <1.0 <1.0 35 7.1 2nd Qtr 6/14/2010 1.2 1,600 <1.0 <1.0 40 6.8 3rd Qtr 8/18/2010 1 1,600 <1.0 <1.0 35 6.7 41h Qtr 10/15/2010 <1.0 1,500 <1.0 <1.0 1st Qtr 2/24/2011 <1.0 1,300 <1.0 <1.0 ai .5.6 2nd Qtr 6/1/2011 <1.0 1,200 <1.0 <1.0 35 6.6 3rd Qtr 8/18/2011 <1.0 1,300 <1.0 <1.0 36 6.8 41h Qtr 11/29/2011 <1.0 1,500 <1.0 <1.0 40 6.6 1 ifCIE)SY 1/24/2012 <1.0 1,360 <1.0 <1.0 38 2nd Qtr 6/14/2012 <1.0 1,000 <1.0 <1.0 42 7.1' 3rd Qtr 9/28/2012 <1.0 1,000 <1.0 <1.0 39 5.0 10/4/2012 41 t
s
ht
cOtr
tr <1.0 10190 <1.0 <1.0 40 6.5 2/13/2013 3.66 1,320 <1.0 <1.0 ...f:i 6.99 2nd Qtr 6/19/2013 <1.0 1,100 <1.0 <1.0 39.1 6.87 3rd Qtr 9/3/2013 <1.0 1,150 <1.0 <1.0 37.6 7.12
tsh Q 4 11/14/2013 1 t Q tt rr 2/5/2014 <1,0 1,280 <1.0 <1.0 6.5
18-.6 .......M
2nd Qtr 5/23/2014 5.47
4.77
1,090
1,020
<1.0
<1.0
<1.0
<1.0 37.4 6.93 3rd Qtr 8/27/2014 <1.0 845 1.4 <1.0 35 4.80 41h Qtr 10/29/2014 <1 0 _1,140 <1 0 <1.0 38.7 6.31
lst Qtr (2) 3/9/2015 <1.0 1,130 <1.0 <1.0 38.3 - 7.06 2nd Qtr 6/8/2015 <1.0 1,260 <1.0 <1.0 40.3 6.07 3rd Qtr 8/31/2015 <1.0 1,060 <1.0 <1.0 45.9 6.28 4th Qtr 10/19/2015 <1.0 1,040 <1.0 <1.0 38 5 1.55 rl st Qtr 3/9/2016 <1.0 974 <1.0 <1.0 41.7 ---Tias 25d Qtr 5/23/2016 <1.0 1,140 <1.0 <1.0 44.4 0.138 3rd Qtr 7/25/2016 <1.0 1,160 <1.0 <1.0 44.7 5.49 4th Qtr 10/13/2016 <1.0 .1330 <1.0 <1.0 44.2 0.746 1st Qtr 3/8/2017 <1.0 519 <1.0 <1.0 41.5 4.44 2nd Cltr 6/13/2017 <1.0 977 <1.0 <1.0 41.8 5.74 3rd Qtr 7/26/2017 <1.0 958 <1.0 <1.0 42.8 5.04 4th Qtr 10/11/2017 <1.0 556 <1.0 <1.0 38.5 5.78 DwioR9.sot.§aE(p( . filafri3y (
STIIINTŠ <7.6 810 <12 23 J 42 0.17 .1.0 70.4 <1.0 <1.0 45.8 4.84 _ 2nd Qtr 6/8/2018 <1.0 942 <1.0 <1.0 42.0 4.36 3rd Car 8/22/2018 <1.0 1,010 <1.0 <1.0 47.3 4.30 4th Qtr 10/22/2018 <1.0 752 <1.0 <1.0 43.2 4.57 Dl IA; NAQRtrcvtt.912p! <5.0 210 <5.0 <56 P:±1.§. 3/8/2019 <1.0 87.2 <1.0 <1.0 40.9 4.51 2nd Qtr 6/5/2019 <1.0 1,040 <1.0 <1.0 44.8 1.43 3rd Qtr 9/4/2019 <1.0 894 <1.0 <1.0 46 1.65 41h Qtr 12/10/2019 <1.0 1270 <1 0 <1 0 44.2 3.91 1 st Qtr 2/19/2020 <1.0 1,190 <1.0 <1.0 47.5 4.67 2nd Qtr 5/27/2020 <1.0 499 <1.0 <1. 0 46.4 0.44 3rd Cl1r 9/4/2020 <1.0 1,060 <1.0 <1.0 43.7 2.22 4th Otr 10/28/2020 <1.0 924 <1.0 <1.0 4..1,9 aA lstQtr 2/23/2021 <1.0 948 <1.0 <1.0 45.4 2../2 (1) As *1 Marrh 2012 both north and so:a who hfe ponds no lonor recensag water
TW4-1 concerted to a chloroform_pututp wet started in 1/14/15
(3) chloroform pumpinuell 1'W4-41 started in Mly 2018
NA = not analyzed
Shaded indicates concentrations exceeding GWQS. Bold and italics indicates the MOL exceeded the GWQS.
J = Approximated value
TABLE 1 (5 of 31)
Historic Summary Of Monitoring Well Analytical Results Up To The 1st Qarter 2021 Chloroform Contamination Investigation
DUSA White Mesa Mill
TW4-2 (chlordonn purnping well staling 1 /10/15) Sampling Event Pararneter
(GWQS) Carbon Tetrachloride (5 pgIL) Chloroform
(70 pg/L)
Chloromethane
(30 pg/L)
Methylene Chloride
(5 pg/L)
Chloride
No GWQS (mg/L) Nitrate, Nitrate -i- Nitrite (10 mg/L) 1st Qtr 3/16/2005 2nd Qtr 5/25/2005 3rd Qtr 8/31/2005
41h Qtr 12/7/2005 1st Qtr 3/9/2006
2nd Qtr 6/14/2006 3rd Qtr 7/20/2006
4th Qtr 11/8/2006 1st Qtr 2/28/2007 2nd Qtr 6/27/2007 3rd Qtr 8/15/2007 4th Qtr 10/10/2007
1st Qtr 3/28/2008 2nd Qtr 6/25/2008 3rd Qtr 9/10/2008 41h Otr 10/15/2008 11/18/2008
1st Qtr 3/11/2009 2nd Qtr 6/23/2009 3rd Qtr 9/14/2009
41h Qtr 12/2912009
1st Qtr 3/312010 2nd Qtr 6/14/2010 3rd Qtr 8/18/2010 41h Qtr 10/15/2010
1st Qtr 2/24/2011 2nd Qtr 6/2/2011 3rd Qtr 8/17/2011
4.t.1) .9p: ...... .1.112*.2.01,1 1 ifutr(2) - 1/24/2012
2nd Qtr 6/14/2012 3rd Qtr 9/4/2012 41h Qtr 10/4/2012
1st Qtr 2/13/2013
2nd Qtr 6/19/2013 3rd Qtr 9/3/2013 41 tsht QQ ttrr 11/14/2013 2/6/2014 2nd Qtr 5/23/2014
3rd Qtr 8/27/2014
4th Qtr 10/30/2014
1st Qtr (2) 3/9/2015
2nd Qtr 6/8/2015 3rd Qtr 8/31/2015 4th Qtr 10/19/2015 1st Qtr 3/9/2016 2nd Qtr 5/23/2016 3rd Qtr 7/25/2016 41h Qtr 10/12/2016 1st Qtr 3/8/2017 2nd Qtr 6/13/2017 3rd Qtr 7/26/2017 415 Qtr 10/11/2017 DWAARG spirt sample DWMRC dtiplisste TW4-50 1st Qtr 3/12/2018
2nd Qtr 6/8/2018 3rd Qtr 8/22/2018 41h Qtr 10/22/2018 1st Qtr 3/8/2019 2nd Qtr 6/5/2019 3rd Qtr 9/4/2019
41h Qtr 12/10/2019
1st Qtr 2/19/2020 2nd Qtr 6/10/2020 3rd Qtr 9/4/2020 41h Qtr 10/28/2020 1 st Qtr 2/23/2021
NA NA <10
<50 <50
<50 <50
NA
<1.0 <1.0
<1.0 <1,0 <1.0 <1.0
<1.0 <1.0 <19 <19 <1.0
<1.0 <1.0 <1.0 <1.0 <1.0
<1.0
<1 0
<1.0 <1.0 <1.0 <1.0 <1.0
2.3 1.8 2.5 2.2
2.1 2.3 2.2 2.4
2.4 2.2 2 2
2
2.6 2.5
2.1 2.4 2.2 1.6 2.8 2
2.1 1.8
2
5.17 2.65 2.41 3.15 7.1 6.05
1.4 2.6 1.44
1.2
1.49
2 6
N/A
3,700 3,750
3,900
. ,500
3,800 3,200 4,120
.1420 2,300 3,000 340
...3,,200
, 3,100 2,800
.829.0 3,100 2,800 3,000
it.:200
3,300 3,300
3 000 3,100 3,000 2,400 3,900 2,500
2,500 2,900
..11,90
3,580 3,110 3,480 .17.40 3,180
2,930 3,170 1680
1,840 1,650 1,060 2,070
1,970 2,070 1,780 1800 1,5/0
1,940 1,310 1,610 1,200 1 200 764
949 980 822 1,040 1,360
797
934 1,880 1,070 1,260 1 130 --,99
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..00
<1.0 <1.0
<1 0 <1.0 <1.0 <1.0 <1.0 <1.0
<1.0 <1.0 <16
<1.0 2 <1.0 <1.0 <1.0
<1.0
<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 <1.0
<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
2.6
NA
NA </o <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
< .0 <1.0
<1.0
<1.0
<1.0 <1.0 <1.0 <1.0 <1.0
<1.0 <1.0 <1 0
<1.0 <1.0 <1.0 <1 0
<1.0 <1.0 <1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0 <1.0 <1.0
<1.0
<1.0
<1 0
<1.0 <1.0 <1.0
<1.0 <1.0
•
68 J 60 J
NA
NA NA
56 56 56
54 55 54
50 49 51
46
42 47 NA 46
44 43 46 42
43 43 41 46 42
48 49 49
52
76 49 46 46.9 44.9 43.9
45.9 45.4 45
44.9 48.1 50
43.4 43.8 42.9
- --;11: 43.6 43.2 43.5 44
43 44.4 41.3 44.3 41.7
40.4
39.8
40.8
45 5
41.9
41.5
N/A
7.7 8.6 8.0
7.8 7.5
7.1
7.4 7.6
7.3 7.8 7.3
21 -.
7.4 7.1 8.0
6.5 6.4 6.6 6.4 6.8
8.7 6.6 6.5 7.0
6.8 6.0 7.0 7.1 71 4.0 7.6 8.1 7.51 9.3
8.39 7.87 9.11 6.2 8 45
5.32 4.3 3.76
5.18 5.30 5.67 4.07
..6:07. 4.74 4.90 5.08 3.25
4.00
--12 3.50 4.83
1.E --
4.38 4.79 3.40 6.07 3.62
3.35 2.34 3.30
42.1 40.6
41.3 38.7 43.3
(1) As of March 2012 both north and south wild life ponds no lonor receiving water
2u\s/4-2 and 1W4-11 converted to a chloroform punleirj, well started in 1/14/15 NA and #N/A(for graph use)= not analged Shaded indicates concentrations exceeding GWQS. Bold and italics indicates the MDL exceeded the GWQS.
J = Approximated value
TABLE 1 (6 of 31)
Historic Summary Of Monitonng Well Analytical Results Up To The 1st Qarter 2021 Chloroform Contamination Investigation
DUSA White Mesa Mill
1W4-3 Sampling Event Parameter (GWQS)
Carbon Tetrachlonde (5 pgIL) Chloroform (70 pg/L) Chloromethane (30 pg/L) Methylene Chlonde (5 pg/L) Chloride No GWQS (mg/L) Nitrate, Nitrate + Nitnte (10 mgIL)
1st Qtr 3/16/2005 NA <1 0 NA NA NA 3 5 2nd Qtr 5/25/2005 NA <1 0 NA NA NA 3 7 3rd Qtr 8/31/2005 <1 0 <1 0 6 4 <1 0 NA 3 5 41h Qtr 12/7/2005 <1 0 • <1 0 <1 0 <1 0 26 3 3
1st Qtr 3/9/2006 <1 0 <1 0 2 3 <1 0 26 3 3
2nd Qtr 6/14/2006 <1 0 <1 0 1 6 <1 0 26 7 1 3rd Qtr 7/20/2006 <1 0 <1 0 2 2 <1 0 26 2 9 4th Qtr 11/8/2006 <1 0 • <1 0 <1 0 <1 0 23 1 5 1st Qtr 2/28/2007 <1 0 <1 0 <1 0 <1 0 22 3 1 2nd Qtr 6/27/2007 <1 0 <1 0 <1 0 <1 0 23 3 3
3rd Qtr 8/15/2007 <1 0 <1 0 <1 0 <1 0 24 3 1
4th Qtr 10/10/2007 <1 0 <1 0 <1 0 <1 0 27 2 8 1st otr 3/28/2008 <1 0 <1 0 <1 0 <1 0 21 2 8 2nd Qtr 6/25/2008 <1 0 <1 0 <1 0 <1 0 19 2 9
3rd Qtr 9/10/2008 <1 0 <1 0 <1 0 <1 0 19 2 7
4th Qtr 10/15/2008 <1 0 <1 0 • <1 0 <1 0 22 2 6 1st Qtr 3/4/2009 <1 0 <1 0 <1 0 <1 0 21 2 5 2nd Qtr 6/23/2009 <1 0 <1 0 <1 0 <1 0 20 2 9
3rd Qtr 9/14/2009 <1 0 <1 0 <1 0 <1 0 21 2 8
4th Qtr 12/29/2009 <1 0 • <1 0 <1 0 • <1 0 22 2 6 1st Qtr 2/23/2010 <1 0 <1 0 <.1 0 <1 0 23 2 8 2nd Qtr 6/14/2010 <1 0 <1 0 <1 0 <1 0 24 3 0 3rd Qtr 8/10/2010 <1 0 <1 0 <1 0 <1 0 22 3 1
4th Qtr 10/15/2010 <1 0 • <1 0 <1 0 <1 0 26 • 3 3
1st Qtr 2/15/2011 <1 0 <1 0 <1 0 <1 0 23 3 5 2nd Qtr 5/25/2011 <1 0 <1 0 <1 0 <1 0 23 3 7 3rd Qtr 8/17/2011 <1 0 <1 0 <1 0 <1 0 23 4 0 4th Qtr 11/14/2011 <1 0 <1 0 <1 0 <1 0 23 4 4 1st Otr (2) 1/17/2012 <1-0 <1 0 <1 0 <1 0 21 7 1
2nd Qtr 5/31/2012 <1 0 <1 0 <1 0 <1 0 24 4 4
3rd Qtr 8/28/2012 <1 0 <1 0 <1 0 <1 0 25 4 9
4th Qtr 10/3/2012 <1 0 <1.0 <1 0 <1 0 25 • 4 8 1st Qtr 2/7/2013 <1 0 <1 0 <1 0 <1 0 23 7 5 05 2nd Qtr 6/28/2013 <1 0 <1 0 <1 0 <1 0 23 8 5 83
3rd Qtr 9/3/2013 <1 0 <1 0 <1 0 <1 0 25 4 90
41h Qtr _ 11/8/2013 <1 0 <1 0 <1 0 <1 0 24 1 5 89
1st Qtr 1/22/2014 <1 0 <1 0 <1 0 <1 0 24 9 6 66 2nd Qtr 5/21/2014 <1 0 <1 0 <1 0 <1 0 24 4 6 01 3rd Qtr 8/13/2014 <1 0 <1 0 <1 0 <1 0 26 5 30
4th Qtr 10/23/2014 <1 0. <1 0 <1 0 <1 0 26 7 • 6 07
1st Qtr 3/11/2015 <1 0 <1 0 <1 0 <1 0 26 2 6 64 2nd Qtr 6/10/2015 <1 0 <1 0 <1 0 <1 0 27 5 5 71 Duplicate TW4-65 <1 0 <1 0 <1 0 <1 0 27 5 3 94 3rd Qtr 8/13/2015 <1 0 <1 0 <1 0 <1 0 27 4 3 88
4th qtr 1st Qtr 10/21/2015 <1 0 <1 0
<1 0
<1 0 < ° •11 < O
<1 0 25 6 5 37
<1 0 32 8 5 83 2nd Qtr 5/25/2016 <1 0 <1 0 <1 0 <1 0 27 9 5 65 3rd Qtr 7/27/2016 <1 0 <1 0 <1 0 <1 0 26 5 6 10 4th Qtr 10/19/2016 <1.0. . <1 0 <1 0 <1 0 29 5 • 6 00
1st Qtr 3/14/2017 <1 0 <1 0 <1 0 <1 0 28 1 6 18'
2nd Qtr 6/14/2017 <1 0 <1 0 <1 0 <1 0 28 7 6 36
3rd Qtr 7/27/2017 <1 0 <1 0 <1 0 <1 0 28 5 6 36 Duplicate 1W4-65 <1 0 <1 0 <1 0 <1 0 28 9 6 24
11
4th Qtr
1st Qtr
10/11/2017
3/14/2018
<1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 • 25 9 29 8 6 32 6 46
Duphcate TW4-65 <1 0 <1 0 <1 0 <1 0 29 5 6 31
2nd Qtr 6/8/2018 <1 0 <1 0 <1 0 <1 0 26 1 6 52 3rd Qtr 8/29/2018 <1 0 <1 0 <1 0 <1 0 31 0 5 53 Duplicate TW4-65 <1 0 <1 0 <1 0 <1 0 31 0 5 44 4th Qtr 11/30/2018 <1 0 <1 0 <1 0 <1 0 27 4 5 85
Duplicate 1W4-65 <1 0 0 •<1 <1 0 <1 0 26 2 • 5 77
1st Qtr 3/13/2019 <1 0 <1 0 <1 0 <1 0 25 5 5 82
2nd Qtr 6/13/2019 <1 0 <1 0 <1 0 <1 0 27 4 6 68 Duplicate TW4-65 <1 0 <1 0 <1 0 <1 0 25 9 6 60 3rd Qtr 9/11/2019 <1 0 <1 0 <1 0 <1 0 26 0 5 12
Duplicate1W4-65 <1 0 <1 0 <1 0 <1 0 22 1 5 76
4th Qtr 12/12/2019 <1 0 <1 0 <1 0 28 • 5 91
1st Qtr - 3/17/2020 <1 0 <1 0 <1 0 < ° <11 0 - 27 7 6 15
Duplicate 1W4-65 <1 0 <1 0 <1 0 <1 0 26 6 38 2nd Qtr 6/10/2020 <1 0 <1 0 <1 0 <1 0 26 2 6 53 Duplicate TW4-65 <1 0 <1 0 <1 0 <1 0 26 7 6 63 3rd Qtr 9/17/2020 <1 0 <1 0 <1 0 <1 0 25 9 6 36
4th Qtr 11/4/2020 <1 0 <1 0 <1 0 <1 0 24 9 6 02
lst Qtr 3/17/2021 <1 0 <1 0 <1 0 <1 0 28 4 6 19
Duplicate 1W4-65 <1 0 <1 0 <1 0 <1 0 27 6 6 64
NA = not analyzed Shaded indicates concentrations exceeding GWQS
TABLE 1 (7 of 31)
Historic Summary Of Monitoring Well Analytical Results Up To The 1st Qarter 2021 Chloroform Contamination Investigation
DUSA White Mesa Mill
TVV4-4 (chloroform purnping well stared in let qtr 2010)
Sampling Event
Parameter (GWQS)
Carbon Tetrachloride
(5 pg/L)
Chloroform (70 pg/L) Chloromethane (30 pg/L) Methylene Chloride (5 pg/L) Chloride No GWQS (mg/L)
Nitrate, Nitrate + Nitrite
(10 mg/L)
1s1 Qtr 3/16/2005 NA 3,100 NA NA NA 10.0
2nd Qtr 5/25/2005 NA 2,400 NA NA NA 11.3
3rd Qtr 8/31/2005 <10 3,200 <10 <10 NA 9.9
41h Qtr 12/7/2005 <50 2,800 <50 <50 54 10.2
1st Qtr 3/9/2006 <50 2660 <50 <50 51 9.5
2nd Qtr 6/14/2006 <50 2,600 <50 <50 48 8.6
3rd Qtr 7/20/2006 <50 2,850 <50 <50 50 9.7
1 11/8/2006 1.7 .2,570 <1.0 <1.0 49 10.1 41 t
s
ht
Q
C ttr
r 2/28/2007 1.5 2,200 <1.0 <1.0 49 9.0
2nd Qtr 6/27/2007 1.7 2,400 <1.0 <1.0 47 9.4
3rd Qtr 8/15/2007 1.5 2,700 <1.0 <1.0 45 9.5
41 tsht
(I
Q tt rr 10/10/2007 3/28/2008 1.5 1.6 1,500 2,800 <1 0 <1.0
<1.0
<1.0 .......... ...... 43 9.2
2nd Qtr 6/25/2008 1.5 2,500 <1.0 <1.0 42 10.8
3rd Qtr 9/10/2008 1.4 2,200 <1.0 <1.0 39 8.8
41h Qtr 10/15/2008 NA #N/A NA NA 44 10.1
1st Qtr 11/18/2008 <2.0 2 500 <2.0 <2.0 NA #N/A
1st Qtr 3/4/2009 1.2 -2,200 <1.0 <1.0 37 10,2
2nd Qtr 6/23/2009 1.2 1,800 <1.0 <1.0 34 8.2
3rd Qtr 9/14/2009 1.1 2,000 <1.0 <1.0 39 8.4
4th Qtr 12/29/2009 1.1 950 <1.0 <1.0 41 7.6
1st Qtr (2) 2/17/2010 1 1,700 <1.0 <1.0 48 6.6
2nd Qtr 6/14/2010 1.2 1,700 <1.0 <1.0 35 7.6
3rd Qtr 8/10/2010 1.3 2,100 <1.0 <1.0 36 7.3
41h Qtr 0/15/2010 1.3 1,700 <1.0 <1.0 38 7.1 ......... lst Qtr 2/23/2011 14 1,800 <10 <10 41 70
2nd Qtr 6/1/2011 1.2 1,700 <1.0 <1.0 35 7.0
3rd Qtr 8/17/2011 <1.0 1,500 <1.0 <1.0 40 6.6
4th Qtr 11/16/2011 1 1 500 <1.0 <1.0 39 7.0 filtrECIY 1/23/2012 <1.0 1,200 <1.0 <1.0 38 7.1
2nd Qtr 6/6/2012 <1.0 1,500 <1.0 <1.0 43 7.1
3rd Qtr 9/4/2012 1.2 1 600 <1.0 <1.0 39 7.1
4th Qtr 1 ,400 <1.0 <1.0 38 7 .....:.9. 1 st Qtr
/
/
2
2
0
01
1 2
3

2
1
/
0
1
/3
1
1,460 <1.0 <1.0 39 .7.36
2nd Qtr 6/29/2013 <1.0 1,330 <1.0 <1.0 39.6 6.30
3rd Qtr 9/3/2013 1.2 1,380 <1.0 <1.0 38.8 7.22
4th Qtr 10/23/2013 5.3 .1,360 <1.0 <1.0 43.9 .7.84 ...........
1st Qtr 1/27/2014 3.88 1,260 <1.0 <1.0 37.4 7.28
2nd Qtr 5/19/2014 4.94 1,220 <1.0 <1.0 47.5 5.91
3rd Qtr 8/11/2014 4.94 1,320 7.1 <1.0 40 5.3
41h Qtr 10/21/2014 <1.0 1 130 <1 0 <1.0 40 7.02
I st Qtr (4) 3/9/2015 1.05 1,350 <1.0 <1.0 37.6 7.7
2nd Qtr 6/10/2015 <1.0 1,280 <1.0 <1.0 41.3 6.33
3rd Qtr 8/31/2015 <1.0 1,220 1.72 <1.0 45.8 6.45
4t6 Qtr 10/19/2015 <1.0 1 19Q <1.0 <1.0 ...__ ..... 38.5 __. 6.27
1st Qtr 3/9/2016 <1.0 1,190 <1M <1.0 39.7 "Ci
2nd Qtr 5/23/2016 1.21 1,780 <1.0 <1 0 41.9 6.56
3rd Qtr 7/27/2016 <1.0 illinlIM-<1.0 <1.0 40.2 7.22
4th Qtr 1st Qtr 10/13/2016 3/8/2017 <1.0 <1.0
1430
1,290
<1.0
<1.0
<1.0
<1.0
40.3 41.7 ---24;
2nd Qtr 6/13/2017 <1.0 1,290 <1.0 <1.0 40.7 7.06
3rd Qtr 7/26/2017 <1.0 1,290 <1.0 <1.0 40.5 6.47
4th Qtr 10/11/2017 <1.0 .1110 <1.0 6.90
1st Qtr 3/12/2018 <1.0 1 160 <1.0 <1.0 42.2 ---6-.12 nazw(s) 6/8/2018 <1.0 1,050 <1.0 <1.0 39.0*- 6.34
3rd Qtr 8/22/2018 <1.0 1,030 <1.0 <1.0 44.6 6.10
4th Qtr 11/28/2018 <1.0 1 140 <1 0 <1.0 41.4 6.02
1st Qtr 3/8/2019 <1M ti5 . go <1.0 <1.0 38.3 7.26
2nd Qtr 6/5/2019 <1.0 1,070 <1.0 <1.0 38.5 10.40
3rd Qtr 9/4/2019 <1.0 989 <1.0 <1.0 39.4 6.32
4th Qtr 1st Qtr 122/11109//22002190 :11 :00 1,140 1,100 <1.0
<1.0
<1.0 ---ti 6.52 4.58
2nd Qtr 5/27/2020 <1.0 1,140 <1.0 <1.0 46.1 7.26
3rd Qtr 9/4/2020 <1.0 1,110 <1.0 <1.0 40.0 7.04
4th Qtr 10/28/2020 <1.0 979 <1.0 <1.0 38.6 6.77
1st Qtr 2/23/2021 <1.0 1,130 <1.0 <1.0 39.8 6.75
(1) As of March 2012 both north and
2LTW4-4 converted to a Chloroform Num g stale< Jr1 10 qtr „
(3) TW4-41 installed as a Chloroform purr2Lig well stared in May 2,,'
WV4-2 Li...r.anited to a chloroform punzia9 well started in 1)14/1.:
NA and #N/Artor graph use) = not analyzed
Shaded indicates concentrations exceeding GWQS. Bold and italics indicates the MDL exceeded the GWCIS.
TABLE 1 (8 of 31)
Historic Summary Of Monitoring Well Analytical Results Up To The 1st Qarter 2021 Chloroform Contamination Investigation
DUSA White Mesa Mill
TW4-5 Sarnpling Event
Parameter
(GWQS)
Carbon Tetrachloride (5 pg/L) Chloroform (70 pg/L)
Chloromethane
(30 pg/L)
Methylene Chloride
(5 pg/L)
Chloride
No GWQS (mg/L)
Nitrate, Nitrate + Nitrite (10 mg/L)
1st Qtr 3/16/2005 NA 120 NA NA NA 4.9
2nd Qtr 5/25/2005 NA 113 NA NA NA 3.7
3rd Qtr 8/31/2005 <2.5 82 5.8 <2.5 NA 6.0
41h Qtr 12/712005 <2.5 2.5 <2.5 56 6.0
1st Qtr 3/9/2006 <2.5 6 3 66 3.1 <S 52 6.0
2nd Qtr 6/14/2006 <2.5 51 3.1 <2.5 51 5.9
3rd Qtr 7/20/2006 <1.0 53.7 <1.0 <1.0 54 6.7
41h Qtr 11/8/2006 <1.0 47.1 <1.0 <1.0 55 2.9
1st Qtr 2/28/2007 <1.0 35 <1.0 <1.0 57 7.8
2nd Qtr 6/27/2007 <1.0 26 <1.0 41.0 45 7.0
3rd Qtr 8/15/2007 <1.0 9.2 <1.0 <1.0 38 7.7
4th Qtr 10/10/2007 <1.0 9.4 <1.0 <1.0 39 8.2
1st Qtr 3/28/2008 <1.0 11 <1S <1S 36 7A
2nd Qtr 6/25/2008 <1.0 9.3 <1.0 <1.0 37 8.7
3rd Qtr 9/10/2008 <1.0 11 <1.0 <1.0 34 7.9
4th Qtr 10/15/2008 <1.0 10 <1.0 <1.0 37 . ...9.:3
l st Qtr 3/4/2009 <1.0 12 <1.0 <1.0 34 7.9
2nd Qtr 6/23/2009 <1.0 13 <1.0 <1.0 37 7.5
3rd Qtr 9/14/2009 <1.0 12 <1.0 <1.0 48 8.3
4th Qtr 12/29/2009 <1.0 8.5 <1.0 <1.0 41 7.5
1st QV 2/25/2010 <1.0 13 <1.0 <1.0 .......a
2nd Qtr 6/14/2010 <1.0 12 <1.0 <1.0 28 7.1
3rd Qtr 8/11/2010 <1.0 12 <1.0 <1.0 38 7.0
4th Qtr 10/15/2010 <1.0 11 <1.0 <1.0 41 7.2
1st Qtr 2/22/2011 <1.0 10 <1.0 <1.0 34 7.0
2nd Qtr 5/26/2011 <1.0 9, <1.0 <1.0 35 7.2
3rd Qtr 8/7/2011 <1.0 10 <1:0 «1.0 37 7.5
4th Qtr 11/16/2011 NA #N/A NA NA 30 6.0
(1).. 12/7/2011 <1.0 7.9 <1.0 <1.0 NA #N/A
1st Cifiql) 1/18/2012 <1.0 7.6 <1.0 <1.0 22 .....E3
2nd Qtr 6/6/2012 <1.0 8.4 <1.0 <1.0 39 - 8.6
3rd Qtr 9/11/2012 <1.0 12.0 <1.0 <1.0 37 8.1
41 tsht (IQ tt rr 10/4/2012
2/13/2013
<1.0
<1.0
8.0 10.8 <1.0 <1.0 <1.0 <10 38 34.3 ---- -8 721.
2nd Qtr 6/13/2013 <1.0 11.2 <1.0 <1.0 36.5 10.70
3rd Qtr 9/5/2013 <1.0 11.6 <1.0 <1.0 39.1 7.79
41h Qtr 11/13/2013 <1.0 14.4 <1.0 <1.0 41.1 7.75
1st Qtr 1/30/2014 <1.0 12.5 <1.0 <1.0 40.5 .-9....16
2nd Qtr 5/22/2014 <1.0 13.4 <1.0 <1.0 51.4 7.78
3rd Qtr 8/14/2014 <1.0 12.0 <1.0 <1.0 44 7.2
Q 10/13/2014 <1.0 14.6 <1.0 <1.0 45.1 8.31 41 tsht tttr
c1
3/12/2015 <1.0 13.8 <1.0 <1.0 45.1 9.32
Duplicate TW4-70 <1.0 13.8 <1.0 <1.0 46.4 8.81
2nd Qtr 6/10/2015 <1.0 13.3 1.07 <1.0 47.3 7.08
3rd Qtr 9/10/2015 <1.0 12.9 <1.0 <1.0 52.2 8.1
4t5 Qtr 10/28/2015 <1.0 11.0 <1.0 <1.0 4 443167 ...... 8 03
1st Qtr 3/17/2016 <1.0 110 <1.0 <1 .0 10.2
2nd Qtr 5/23/2016 <1.0 13.6 <1.0 <1.0 45.9 8.98
3rd Qtr 8/3/2016 <1.0 10.8 <1.0 <1.0 44.6 8.49
4th Qtr (3) 10/26/2016 <1.0 9.9 <1.0 <1.0 47.8 8.32
<1.0 12.0 <1.0 <1.0 49.5 8.34
e TW4-76 01 rt rt 3/15/2017 <1.0 12.6 <1.0 <1.0 44.7 8.44
2nd Qtr 6/15/2017 <1.0 14.6 <1.0 <1.0 47.3 8.52
3rd Qtr 8/8/2017 <1.0 14.6 <1.0 <1.0 48.6 8.52
41h Qtr 10/11/2017 <1.0 13.8 <1.0 <1.0 42.5 8.57
DVVMRC split sarrOa <0.19 12 <0.3 47
1st Qtr 3/12/2018 <1.0 15.2 <1.0 <1.0 51.2 8.36
2nd Qtr 6/13/2018 <1.0 13.9 <1.0 <1.0 47.3 9.24
3rd Qtr 8/30/2018 <1.0 15.4 <1.0 <1.0 54.7 7.34
Duplicate TW4-70 <1.0 15.3 <1.0 <1.0 55.9 7.28
41h Qtr 11/28/2018 <1.0 15.6 <1.0 <1.0
<1.0
<1.0
49.8 7.67
Olrer
te TW4-70
3/16/2019
<1O <1.0 16.2 14.1
48 5.
47.6
180 7:8 <1.0 <1.0
2nd Qtr 6/13/2019 <1.0 15.8 <1.0 <1.0 49.3 7.62
3rd Qtr 9/11/2019 <1.0 14.6 <1.0 <1.0 46.1 7.04
Duplicate TW4-70 <1.0 13.6 <1.0 <1.0 45.8 6.89
41h Qtr 12/14/2019 <1.0 15.7 <1.0 <1.0 53.1 6.97
<1.0 16.0 <1.0 <1.0 52.5 . 719. Dl tftigr te TW4-70 3/17/2020 <1.0 14.8 <1.0 st7.10 <1.0 48.3
Duplicate lla/4-70 <1.0 14.8 <1.0 <1.0 48.4 7.72
2nd Qtr 6/11/2020 <1.0 15.4 <1.0 <1.0 49.5 7.83
3rd Qtr 9/18/2020 <1.0 14.8 <1.0 <1.0 47.0 6.37
41h Qtr 11/4/2020 <1.0 15.6 <1.0 <1.0 50.2 6.19
lst Qtr 3/18(2021 <1.0 12.9 <1.0 <1.0 46 7.43
(1) VOCs were resarnpled because laboratory missed holding sine. 2) As of March 2012 both north and south wild Me ponds no lonor recemlng wate
2) chloroform purapnei TW4-30started rn 11/20/18 NA and #N/A(for graphs) = not analyzed Shaded indicates concentrations exceeding GWQS.
TABLE 1 (9 of 31) Historic Summary Of Monitoring Well Analytical Results Up To The 1st Oarter 2021
Chloroform Contamination Investigation DUSA White Mesa Mill
TW4-6 Sampling Event Parameter (GWQS)
Carbon Tetrachloride (5 pg/L)
Chloroform
(70 pgIL)
Chloromethane
(30 pg/L)
Methylene Chloride
(5 pg/L)
Chloride
No GWQS (mg/L)
Nitrate, Nitrate . Nitrite
(10 mg/L)
lst Qtr 3/16/2005 NA <1.0 NA NA NA 0.2
2nd Qtr 5/25/2005 NA 2.5 NA NA NA 0.4 3rd Qtr 8/31/2005 <1.0 10 2.8 <1.0 NA 0.8 12/7/2005 <1.0 1.3 <1.0 32 0.9 41 tsht QQ tt
r
r
3/9/2006 <1.0 17 3 1 <1.0 <1.0 31 1.2
2nd Qtr 6/14/2006 <1.0 19 <1.0 <1.0 30 1.0
3rd Qtr 7/20/2006 <1.0 11 <1.0 <1.0 37 0.8 4th Qtr 11/8/2006 <1.0 42.8 <1.0 <1.0 . 65 14 lstQtr 2/28/2007 <1.0 46 <1.0 <1.0 32 1.8
2nd Qtr 6/27/2007 <1.0 11 <1.0 <1.0 38 0.6
3rd Qtr 8/15/2007 <1.0 18 <1.0 <1.0 36 0.7 4th Qtr 10/10/2007 <1.0 18 <1.0 <1.0 35 ....9.1 lstQtr 3/28/2008 <1.0 52 <1.0 <1.0 33 1.1
2nd Qtr 6/25/2008 <1.0 24 <1.0 <1.0 35 0.9
3rd Qtr 9/10/2008 <1.0 39 <1.0 <1.0 35 1.1
4th Qtr 10/15/2008 <1.0 37 <1.0 <1.0 3 5 .1.0 .... 1st Qtr 3/4/2009 <1.0 81 <1.0 <1.0 2.2.
2nd Qtr 6/23/2009 <1.0 120 <1.0 <1.0 37 2.7
3rd Qtr 9/14/2009 <1.0 280 <1.0 <1.0 37 5.0
4th Qtr 12/29/2009 <1 0 250 <1 0 <1.0 41 6.1
1st Qtr (5) 2/25/2010 <1.0 1000 <1.0 <1.0 45 - 1.6
2nd Qtr 6/14/2010 <1.0 590 <1.0 <1.0 33 2.5
3rd Qtr 8/11/2010 <1.0 630 <1.0 <1.0 31 3.9
4th Qtr 10/15/2010 <1.0 420 <1.0 <1.0 41 ..,4,8 lstQtr 2/22/2011 <1.0 47 <1.0 <1.0 40 0.7
2nd Qtr 5/26/2011 <1.0 9.6 <1.0 <1.0 42 0.3
3rd Qtr 8/7/2011 <1.0 16 <1.0 <1.0 39 0.3
4th Qtr 11/16/2011 NA #N/A NA NA 36 0.8 (1) 12/7/2011 <1.0 21 <1.0 <1.0 NA #N/A
.(2)... 11/16/2011 <1.0 50 <1.0 <1.0 33 6,8 MitifF(4) 1/18/2o12 <1.0 38 <1.0 <1.0 38 0.7
2nd Qtr 6/6/2012 <1.0 4.7 <1.0 <1.0 40 - 0.2
3rd Qtr 9/11/2012 <1.0 6.9 <1.0 <1.0 21 0.1
4th Qtr 10/4/2012 <1.0 9 <1.0 <1.0 .....4.151.1 .6,2.
1st Qtr 2/13/2013 01.0 6.89 <1.0 <1.0 0.2
2nd Qtr 6/13/2013 <1.0 4.86 <1.0 <1.0 37.9 0.2 3rd Qtr 9/5/2013 <1.0 5.93 <1.0 <1.0 40.6 0.2
4t5 Qtr 11/13/2013 <1.0 5.51 <1.0 <1.0 40.2 .1.:5. 1st Qtr 1/29/2014 <1.0 5.7 <1.0 01.0 40.6 0.2
2nd Qtr 5/22/2014 01.0 10.3 <1.0 <1.0 37 0.3
3rd Qtr 8/14/2014 <1.0 202 <1.0 <1.0 40 4.2 (3) 9/24/2014 <1.0 260 <1.0 <1.0 NA #N/A
4th Qtr 10/29/2014 <1.0 723 <1.0 <<11..0 0 41.1 6.9
1st Qtr 3/12/2015 <1.0 1,180 <1.0 41.2 5.3
2nd Qtr 6/10/2015 <1.0 1,040 01.0 <1.0 41.6 5.9 3rd Qtr 9/10/2015 <1.0 1,040 <1.0 <1.0 47 6.8
4th Qtr 10/29/2015 <1.0 843 <1.0 <1.0 40.2 _ 5.6
1st Qtr 3/22/2016 <1.0 834 <1.0 <1.0 42.3 6.79
2nd Qtr 6/8/2016 <1.0 486 <1.0 <1.0 44.1 3.19
3rd Qtr 7/27/2016 <1.0 433 <1.0 <1.0 42.2 3.85
41 tsht orl tt rr 0/26/2016 3/16/2017 <1.0 <1.0 301 288 <1.0 <1.0 <1.0 <1.0 46.1 42.1 33.
.7
154
2nd Qtr 6/21/2017 <1.0 239 <1.0 <1.0 42.6 2.42
3rd Qtr 8/8/2017 <1.0 129 <1.0 <1.0 42.9 1.71
4th Qtr 0/11/2017 <1.0 121 <1.0 <1.0 37.6 1.71
1st Qtr 3/20/2018 <1.0 159 <1.0 <1.0 43.1 1.96
2nd Qtr (6) 6/14/2018 <1.0 74.9 <1.0 <1.0 40.2 1.48
3rd Qtr 9/5/2018 <1.0 53.2 <1.0 <1.0 44 1.18
4th Qtr 12/12/2018 <1.0 37.0 <1.0 11:00 20.0 0.90
1st Qtr 3/19/2019 <1.0 23.2 <1.0 41 -15785
2nd Qtr 6/13/2019 <1.0 15.8 <1.0 <1.0 38.1 0.484
3rd Qtr 9/11/2019 <1.0 15.8 <1.0 <1.0 39.7 0.412
4th Qtr 12/14/2019 <1.0 7.4 <1.0 <1.0 45.7 0.244
1st Qtr 3/17/2020 <1.0 6.93 <1.0 <1.0 43.2 0.222
2nd Qtr 6/11/2020 <1.0 4.9 <1.0 <1.0 42.4 0.205
3rd Qtr 9/18/2020 <1.0 3.6 <1.0 <1.0 40.5 0.144
4th Qtr 11/4/2020 <1.0 4.61 <1.0 <1.0 42.9 0.197
1st Qtr 3/18/2021 <1.0 3.78 <1.0 <1.0 41 6 0.205
(1) VOCs were resampled because laboratory missed holding tme. (2) Results of the 7W4-70 the duplicate sample for 7W4-6. (3) Reanalyzed for VOCs ony. (4) As of March 2012 both north and south wild life ponds no lonzr recewir29 water
Ilhloroform amving_wee 7W4-4 stared in 181.34 2010 (ea Chloroform ermping_well TW4-41 installed May 2018
NA and #N/A(for graphs). not analyzed Shaded indicates concentrations exceeding GWQS.
TABLE 1 (10 of 31)
Historic Summary Of Monitoring Well Analytical Results Up To The 1st garter 2021 Chloroform Contamination Investigation
DUSA White Mesa Mill
TW4-7
Sampling Event
Parameter
(GWQS) Carbon Tetrachloride
(5 pg/L)
Chloroform
(70 pg/L)
Chloromethane
(30 pg1L)
Methylene Chloride
(5 pg/L)
Chloride
No GWQS (mg/L)
Nitrate, Nitrate . Nitrite
(10 mg/L)
1st Qtr 3/16/2005 NA 3,100
•
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VI
VV
.V
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I
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V
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''
v v v v v v v

NA NA 5.2
2nd Qtr 5/25/2005 NA 2,700 NA NA 5.4 3rd Qtr 8/31/2005 <10 3,100 <10 NA 5.2 4th Qtr 12/7/2005 <50 2 500 <50 52 5.3
1st Qtr 3/9/2006 <50 1,900 <50 48 1 2nd Qtr 6/14/2006 <50 2,200 <50 47 4.5
3rd Qtr 7/20/2006 <50 2,140 <50 51 4.7 41h Qtr 11/8/2006 1.5 2,160 <1.0 49 16. l st Qtr 2/28/2007 1.1 1,830 <1.0 47 a
2nd Qtr 6/27/2007 1.5 2,600 <1.0 45 5.1
3rd Qtr 8/15/2007 1.4 2 300 , <1.0 44 4.7
4.1h.gr_.... ...19_ .c..9/39,91 1.2 1 900 <1.0 45 4.7 .1 sf Qtr 3/20/2008 1.3 2,200 <1.0 43 4.2
2nd Qtr 6/25/2008 1.3 1,800 <1.0 43 4.8
3rd Qtr 9/10/2008 1.4 1,600 01 0 35 4.16
4th Qtr 10/15/2008 NA #N/A NA 40 4.01 11/18/2008 <2.0 2,500 <2.0 NA #N/A 1st Qtr 3/11/2009 1.2 1,800 <1.0 35 3.7
2nd Qtr 6/23/2009 <1.0 1,400 <1.0 37 30
3rd Qtr 9/14/2009 1 1,500 <1.0 37 4.1 4t 1 sh Q l Qtrtr 12/29/2009 2/25/2010 <1.0 <1.0 1300 , 1,200 <1.0 <1.0 37 35 ...,1
2nd Qtr 6/14/2010 <1.0 1,100 <1.0 31 3.9
3rd Qtr 8/11/2010 1 1,500 <1.0 36 3.9
41h Qtr 10/15/2010 <1.0 1 100 .. 38 1st Car 2/23/2011 <1.0 1,300 <i ..6 ' ''.45 3.6 2nd Qtr 6/1/2011 <1.0 1,200 <1.0 35 4.0
3rd Qtr 8/18/2011 <1.0 1,200 <1.0 37 4.1
4th Qtr 11/29/2011 <1.0 1000 <1.0 37 3.8
fife:itiTfr 1i19/2012 Zro-------- ---"" low <1.0 37 3.9
2nd Qtr 6/14/2012 <1.0 790 <1.0 41 4.0
3rd Car 9/13/2012 <1.0 870 <1.0 40 3.8
4th Qtr 10/4/2012 <1.0 940 <1.0 41 3.8 1st Qtr 2/13/2013 <1.0 940 <1.0 37.7 3.51 2nd Qtr 6/18/2013 <1.0 953 <1.0 39.3 4 3rd Qtr 9/12/2013 <1.0 1,040 <1.0 36.4 4.17
41h Qtr 11/14/2013 <1 0 1 050_ <1 0 37.2 4.13
1st Qtr 2/5/2014 5,41 946 <1.0 38.2 4.24
2nd Qtr 5/22/2014 4.78 847 <1.0 37.7 4.19 3rd Qtr 8/27/2014 <1.0 857 <1.0 39 2.9
4th Qtr 10/30/2014 <1 0 926 <1.0 40.2 3.68
1st Qtr (2) 3/18/2015 <1.0 942 <1.0 40.4 4.25
2nd Qtr 6/11/2015 <1.0 950 <1.0 42.1 2.62
3rd Qtr 9/10/2015 <1.0 897 <1.0 46.7 4.72
4th Qtr 10/29/2015 <1.0 847 <1.0 40.6 3.49
1st Qtr 3/22/2016 <1.0 834 <1.0 42.4 4.43
2nd Qtr 6/8/2016 <1.0 909 <1.0 44.1 3.75 3rd Qtr 8/4/2016 <1.0 1,000 <1.0 <1.0 42.3 4.21
4th QV 10/26/2016 <1.0 886 <1.0 <1.0 45.8 4.33
1st Qtr 3/21/2017 <1.0 986 <1.0 <1.0 40.5 3.87
2nd Car 6/21/2017 <1.0 968 <1.0 <1.0 43.3 4.15
3rd Qtr 8/4/2017 <1.0 1,070 <1.0 <1.0 44.7 4.20 41h Qtr 10/11/2017 <1.0 884 01.0 <1.0 43.7 4.35 DWMRC s sampt!... <7.6 890 <12 7J 4,3.9 1st Qtr 3/21/2018 <1.0 721 <1.0 <1.0 44,5 3.96i
2nd Qtr 6/14/2018 01.0 751 <1.0 <1.0 41.5 4.45
3rd Qtr <1.0 781 <1.0 <1.0 48.5 4.34 4th Qtr 12/13/2018 <1.0 838 <1.0 <1.0 42.8 3.98
1st Qtr 3/20/2019 <1.0 736 <1.0 <1.0 41.3 4.01
2nd Qtr 6/19/2019 <1.0 862 <1.0 <1.0 43.0 4.19
3rd Qtr 9/12/2019 <1.0 801 <1.0 <1.0 39.6 3.76
4th Qtr 12/18/2019 <1.0 546 <1.0 <1.0 47.2 3.11 1st Qtr 3/18/2020 <1.0 746 <1 0 <1.0 42.1 3.75 2nd Qtr 6/12/2020 <1.0 864 <1.0 <1.0 44.1 4.06 Deplicate TW4-75 <1.0 871 <1.0 <1.0 43.1 4.19
3rd Qtr 9/19/2020 <1.0 971 <1.0 <1.0 41.5 3.87
4th Qtr 11/11/2020 <1.0 967 <1.0 <1.0 42.8 4.40
DWMRC. spat samptl4.._ <10 930 <20 <20 43 _ .....:9.9. l st Qtr - 3/24/2021 <1.0 875 <1.0 <1.0 46.2 4.25
it) As of March 2012 both north nd south wad life Eonds no le ger recelving wat
12) chloroform pulping wets TW4-1 and TW4-2 started in 1/14/15 MA and #14/Arfor graphs) - not analyzed Shaded indicates concentrations exceeding GWQS. Bold and italics indicates the MDL exceeded the GWQS. J = ApProximated value
TABLE 1 (11 of 31) Historic Summary Of Monitoring Well Analytical Results Up To The 1st Qarter 2021
Chloroform Contamination Investigation
DUSA White Mesa Mill
TW4-8
Sampling Event
Parameter
(GWQS)
Carbon Tetrachloride (5 pg1L)
Chloroform
(70 pg/L)
Chloromethane
(30 pg/L)
Methylene Chloride
(5 pgIL)
Chloride
No GWQS (mg/L)
Nitrate, Nitrate -i- Nitrite
(10 mg/L)
1st Qtr 3/16/2005 NA 10 NA NA NA <0.1
2nd Qtr 5/25/2005 NA <1.0 NA NA NA 0.2
3rd Qtr 8/31/2005 <1.0 1.1 1.7 NA NA <1.0
40.91r.. ... 12/712005 fif Gib'. - .T9/2066 .:1..:P... <1.0 <1.0 1,3 <1.0 2.1 <1.0 <1.0 41 39 <1.0 -0.3
2nd Otr 6/14/2006 <1.0 1.8 1.0 <1.0 37 <1.0
3rd Qtr 7/20/2606 <1.0 <1.0 <1.0 <1.0 39 0.1
4th Car 11/8/2006 <1.0 <1.0 <1.0 •<1.0 40 <.1
1st QV 2/28/2007 <1.0 2.5 <1.0 <1.0 39 0.7
2n4 Qtr 6/27/2007 <1.0 2.5 <1.0 <1.0 42 0.2
3rd Ott' 8/15/2007 <1.0 1.5 <1.0 <1.0 42 <1.0
4.,111.91r._ ...I.0/.I.012027 .1..:c2..... .. .. ....,§. 1....P........ <1.0 .9 .9 § 1 st Qtr 3/28/2008 <1.0 <1.0 <1.0 2nd Qtr 6/25/2008 <1.0 <1.0 <1.0 <1.0 45 <1.0
3rd Qtr 9/10/2008 <1.0 <1.0 <1.0 <1.0 39 <0.05
4th Qtr 10/15/2008 <1.0 <1.0 <1.0 <1.0 44 <0.05
1st Qtr 3/4/2009 <1.0 <1.0 <1.0 <1.0 42 <9.1 2nd Qtr 6/23/2009 <1.0 <1.0 <1.0 <1.0 44 <0.1
3rd Qtr 9/14/2009 <1.0 <1.0 <1.0 <1.0 44 <0.1
4th Qtr 12/17/2009 01.0 <1.0 <1.0 <1.0 51 <0.1
1st Qtr 2/24/2010 <1.0 <1.0 <1.0 <1.0 57 <0.1 2nd Qtr 6/14/2010 <1.0 <1.0 <1.0 <1.0 42 <0.1
3rd Qtr 8/18/2010 <1.0 <1 0 <1.0 <1.0 45 <0.1
41r.i..glr........ ...10/1.51.1.0., 5.1.:9. .. .. <1.0 <1.0 <1.0 46 ..P. .. 1st Qtr 2/16/2011 <1.6 <1.0 <1.0 <1.0 52 <0.1
2nd Qtr 5/25/2011 <1.0 <1.0 <1.0 <1.0 45 0.1
3rd Qtr 8/16/2011 <1.0 <1.0 <1.0 01.0 46 0.1
415 Qtr 11/16/2011 45 0.2
(11_ 12/7/2011 <1.0 <1.0 <1.0 NA N/A
Tiftff(3). 1/18/2012 <1.0 <1.0 <1.0 <1.0 45 0.3
2nd Oh' 5/13/2012 • 3rd Qtr 8/29/2012 4th QV 10/3/2012
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0
<1.0 <1.0 . 0: <;1111 . : 0
48 44
47 <0.1
0. 2 0.1
1st Qtr 2/7/2013 <1.0 <1.0 <1.0 <1.0 46.6 0.41
2nd Qtr 5/30/2013 <1.0 <1.0 <1.0 <1.0 45.5 <0.1
3rd Otr 9/5/2013 <1.0 <1.0 <1.0 <1.0 47.5 0.1
41h Otr 11/7/2013 <1.0 <1.0 <1.0 <1.0 46 1 <0 1
1st Qtr 1/23/2014 <1.0 63.8 <1.0 <1.0 48.5 0.166
(2) 2/6/2014 <1.0 100 <1.0 <1.0 46.5 0.166
2nd Qtr 5/22/2014 <1.0 122 <1.0 <1.0 53 0.538
3rd Qtr 8/27/2014 <1.0 107 <1.0 <1.0 47 0.6
4th Qtr 10/29/2014 <1.0 191 <1.0 <1.0 46.7 0.914
lst Qtr (4) 3/12/2015 <1.0 - 961 <1.0 <1.0 49.6 2.3
21rd Otr 6/11/2015 <1.0 981 <1.0 <1.0 53 1.88
3rd Qtr 9/10/2015 <1.0 747 <1.0 <1.0 59.6 1.96
r 10/29/2015 <1.0 770 <1.0 <1.0 52 2.2 tsht QQ t rt 141 3/17/2016 <1.0 634 <1.0 <1.0 54.2 2.48
2nd Qtr 6/8/2016 <1.0 595 <1.0 <1.0 56.7 2.14
3rd Qtr 8/4/2016 <1.0 522 <1.0 <1.0 56.9 2.10
41h Qtr 10/27/2016 <1.0 472 <1.0 <1.0
1st Qtr 3/21/2017 <1.0 359 <1.0 <1.0 57.4 . 2.06
2nd Qtr 6/21/2017 <1.0 256 <1.0 <1.0 58.8 1.97
3rd Qtr 8/4/2017 <1.0 223 <1.0 <1.0 61.2 1.64
14Aptr......... 10/11/2017 <1.0 214 <1.0 <1.0 52.2 1.92
Dephcate TW4-75 <1.0 194 1.12 <1.0 56.2 1.71
DWMRC spteample.. <1.9 230 4.7 J <3.0 1.90
1st Qtr 3/21/2018 <1.0 220 <1.0 <1.0 60.8 1.36
Deplicate 1W4-75 <1.0 171 <1.0 <1.0 60.8 1.36
2nd Qtr 6/14/2018 <1.0 155 <1.0 <1.0 53.8 1.31
3rd Qtr 9/5/2018 <1.0 137 <1.0 <1.0 63.2 1.40
12/13/2018 <1.0 93.8 <1.0 <1.0 53.1 1.35 41 tsht ctQttrr 3/19/2019 <1.0 103 <1.0 <1.0 54.3 1.23
2nd Car 6/19/2019 <1.0 96 <1.0 <1.0 56.5 1.1
3rd Qtr 9/12/2019 <1.0 75.4 <1.0 <1.0 52 0.999
Deplicate TW4-75 <1.0 75.6 <1.0 <1.0 52.5 1.030
4th Otr 12/18/2019 <1.0 84.4 <1.0 <1.0 60.1 1.21
1st Qtr 3/18/2020 <1.0 55.0 <1.0 <1.0 53.8 1.04
2nd Qtr 6/12/2020 <1.0 53.8 <1.0 <1.0 56.9 1.06
3rd Qtr 9/18/2020 <1.0 39.6 <1.0 <1.0 52.6 0.894
4th Qtr 11/11/2020 <1.0 51.3 <1.0 <1.0 54.7 1.27
Deplicate1W4-70 <1.0 52.9 <1.0 <1.0 49.9 1.27
DWMIRCeplit sample_ <10 560 <20 <20 56 0.16 H
1st Qtr 3/18/2021 <1.0 26.9 <1.0 <1.0 52.8 1.00
(1) VOCs were reearnpled because laboratory missed holding rne.
(2) Resampled to verify chloro(orm concentrabon (hat was collected on 1/23/14.
21 As of March 2012 both north and south wild life aends no lo 2er reoentu water
L7) chloroform purainz,,,vells TW4-1 and 1W4-2 started in 1/14/15
NA and #141A(for graphs) = not analyzed
Shaded indicates concentrations mceeding GWOS.
J = ApproPmated value
H = Sample was analyzed beyond holding times and may not be accureete concentration.
TABLE 1 (12 of 31)
Historic Summary Of Monitoring Well Analytical Results Up To The 1st Qarter 2021
Chloroform Contamination Investigation
DUSA White Mesa Mill
TW4-9
Sampling Event
Parameter
(GWQS)
Carbon Tetrachloride
(5 pg/L)
Chloroform
(70 pg/L)
Chloromethane
(30 pg/L) Methylene Chloride
(5 pgIL)
Chloride
No GWQS (mg/L)
Nitrate, Nitrate . Nitdte
(10 mg/L) 1st Qtr 3/16/2005 NA 3.8 NA NA NA 1.3 2nd Qtr 5/25/2005 NA 1.2 NA NA NA 1.3 3rd Qtr 8/31/2005 <1.0 <1.0 2.9 <1.0 NA 1.3 4th Qtr 12/7/2005 <1.0 <1.0 <1.0 <1.0 42 1.3 1st Qtr 3/9/2006 <1.0 <1.0 2.6 <1.0 38 1.5 2nd Qtr 6/14/2006 <1.0 19 2.7 <1.0 39 1.5 3rd Qtr 7/20/2006 <1.0 <1.0 <1.0 <1.0 41 0.9 415 Qtr 11/8/2006 <1.0 <1.0 <1.0 <1.0 44 1st Qtr 2/28/2007 <1.0 <1.0 <1.0 <1.0 --.001 2nd Qtr 6/27/2007 <1.0 21 <1.0 <1.0 42 1.3 3rd Qtr 8/15/2007 <1.0 9.5 <1.0 <1.0 38 1.8 4t6 Qtr 10/10/2007 <1.0 8.7 <1.0 <1.0 40 1st Qtr 3/28/2008 <1.0 1.3 <1.0 <1.0 35 2.1 2nd Qtr 6/25/2008 <1.0 1 <1.0 <1.0 35 2.3 3rd Qtr 9/10/2008 <1.0 <1.0 <1.0 <1.0 28 2.79 4th Qtr 10/15/2008 <1.0 <1.0 <1.0 <1.0 58 1.99 1st Qtr 3/4/2009 <1.0 <1.0 <1.0 <1.0 30 2.5 2nd Qtr 6/23/2009 <1.0 <1.0 <1.0 <1.0 30 2.3 3rd Qtr 9/14/2009 <1.0 <1.0 <1.0 <1.0 30 2.5 41h Qtr 12/17/2009 <1.0 <1.0 <1.0 01.0 37 1.7 lat Qtr 2/23/2010 <1.0 <1.0 <1.0 <1.0 47 1.4 2nd Qtr 6/14/2010 <1.0 <1.0 <1.0 <1.0 33 1.5 3rd Qtr 8/13/2010 <1.0 <1.0 <1.0 <1.0 40 1.2 10/15/2010 <1.0 <,11 "00 <1.0 <1.0 34 1.8 1st Qtr 2/17/2011 <1.0 <1.0 <1.0 41 1.3 2nd Qtr 5/25/2011 <1.0 <1.0 <1.0 <1.0 38 3.4 3rd Qtr 8/16/2011 <1.0 <1.0 <1.0 <1.0 21 4 4th Qtr 11/16/2011 NA NA NA NA 38 2.3 (1) 12/7/2011 <1.0 <1.0 <1.0 <1.0 NA #N/A 1st CAM) 1/1800.2 <to <to <to <to 28 2.3
2rid Qtr 5/31/2012 <1.0 <1.0 <1.0 01,0 23 4.0 3rd Qtr 8/30/2012 <1.0 <1.0 <1.0 <1.0 22 3.9 41h Qtr 102;37;22001123 :11:00 • <1.0 <1.0 <1.0 21 3.8 1st Qtr <1.0 <1.0 <1.0 20.6 4.49 2nd Qtr 5/30/2013 <1.0 <1.0 <1.0 <1.0 21.4 4.49
3rd Qtr 9/5/2013 <1.0 01.0 <1.0 <1.0 22.7 4.03 4th Qtr 11/7/2013 <1.0 <1.0 <1.0 <1.0 23.6 .....4,87 lst Qtr 1/29/2014 <1.0 <1.0 <1.0 <1.0 22 .4.6 2nd Qtr 5/22/2014 <1.0 6.9 <1.0 <1.0 24 3.44 3rd Qtr 8/14/2014 <1.0 47 <1.0 <1.0 27 2.7 4th Qtr 10/29/2014 <1.0 101 <1.0 <1.0 25 4.29 1st Qtr 3/12/2015 <1.0 53.5 <1.0 <1.0 29.5 3.28 2nd Qtr 6/11/2015 <1.0 35.1 <1.0 <1.0 35.3 1.83 3rd Qtr 9/3/2015 <1.0 48 <1.0 <1.0 39.3 1.44 4th Qtr 10/28/2015 <1.0 68.4 <1.0 <1.0 29.2 .. 2,89 1st Qtr 3/17/2016 <1.0 74.3 <1.0 <1.0 33.6 2.51 2nd Qtr 6/8/2016 <1.0 76.2 <1.0 <1.0 35.1 2.16 3rd Qtr 8/3/2016 <1.0 76.8 <1.0 <1.0 33.6 2.11 4th Qtr 10/26/2016 <1.0 76.0 <1.0
:11'..190.. 1st Qtr 3/17/2017 <1.0 113 <1.0 34..5 2.18 2nd Qtr 6/21/2017 <1.0 113 <1.0 <1.0 35.9 1.92 3rd Qtr 8/3/2017 <1.0 118 <1.0 <1.0 37 1.90 4th Qtr 10/11/2017 <1.0 132 <1.0 <1.0 32 2.18 DWMRC spat sem& <0.98 120 <1.5 1.6 J 35 .20 1st otr 3/21/2018 <1.0 159 <1.0 <1.0 38.3 1.85 2nd Qtr 6/4/2018 <1.0 134 <1.0 <1.0 35.7 1.85 Deplmate TW4-75 <1.0 132 <1.0 <1.0 35.2 1.91 3rd Qtr 9/5/2018 <1.0 94.2 <1.0 <1.0 43.4 1.04 Dephcarte TW4-75 <1.0 92.4 <1.0 <1- 0 42.7 1.11 4th Qtr 12/13/2018 <1.0 109 <1.0 <1.0 36.3 1.23 15t Qtr 3/1912019 <1.0 86A <1.0 <1.0 36.9 1.09 2nd Qtr 6/19/2019 <1.0 68.1 <1.0 <1.0 38.3 0.785 3rd Car 9/11/2019 <1.0 66.0 <1.0 <1.0 35.2 0.904 41h Qtr 12/18/2019 <1.0 54.8 <1.0 <1.0 40.1 0.744 1st Qtr 3/18/2020 <1.0 48.9 <1.0 <1.0 37.7 0.855 2nd Qtr 6/12/2020 <1.0 55.1 <1.0 <1.0 39.5 0.990 Dephcate TW4-70 <1.0 56.4 <1.0 <1.0 39.6 1.010 3rd Qtr 9/18/2020 <1.0 45.0 <1.0 <1.0 36.7 0.867 4th Qtr 11/11/2020 <1.0 47.1 <1.0 <1.0 37.2 1.11 CANIMRC split sample <10 48.0 <20 <20 38 0.97 OWMRC Duplicate sample <10 46.0 <20 <20 38 0.97 (1W4-81)
1st Mr 3/18/2021 <1.0 39.0 <1.0 <1.0 40.7 1.06 Deplicate 1W4-70 <1 0 38.2 <1 0 <1.0 38.7 1.07 (1) VOCs were resampled because laboratory missed holding time.
(2) As of March 2012 botri NA and #N/ATfor graphs) = not analyzed Shaded indicates concentrations exceeding GWQS. = Approximate value
TABLE 1 (13 of 31) Historic Summary Of Monitoring Well Analytical Results Up To The 1st Qarter 2021 Chloroform Contamination Investigation
DUSA White Mesa Mill
TW4-10 Sampling Event Parameter
(GWQS) Carbon Tetrachloride
(5 PO-)
Chloroform
(70 pg/L)
Chloromethane
(30 pgIL)
Methylene Chloride
(5 pg/L) Chloride No GWQS (mg/L) Nitrate, Nitrate ..- Nitrite (10 mg/L) 1st Qtr 3/16/2005 NA 140 NA NA NA 1.6 2nd Qtr 5/25/2005 NA 62 NA NA NA 0.8 3rd Qtr 8/31/2005 <2.5 110 6.2 <2.5 NA 1.1 41h Qtr 12/7/2005 <2.5 300 <2.5 <2.5 52 3.3 1st Qtr 319/2006 <5.0 190 <5.0 <5.0 50 24 20d Qtr 6/14/2006 <5.0 300 <5.0 <5.0 54 3.5 3rd Qtr 7/20/2006 <5.0 504 <5.0 <5.0 61 6.8 41h Qtr 11/8/2006 <1.0 452 1.6 <1.0 58 5.7 1st Qtr 2/28/2007 <1O SOO <1.0 <1.0 2 7.3 2nd Qtr 6/27/2007 <1.0 350 <1.0 <1.0 54 5.1 3rd Qtr 8/15/2007 <1.0 660 <1.0 <1.0 59 7.3 4th Qtr 10/10/2007 <1.0 470 <1.0 <1.0 1st Qtr 3/28/2008 <1.0 620 <1.0 <1.0 55 7.3 2nd QV 6/25/2008 <1.0 720 <1.0 <1.0 58 9.9 3rd Qtr 9/10/2008 <1.0 660 <1.0 <1.0 51 9.23 4th Qtr 10/15/2008 NA #N/A NA NA 61 10.5 11/18/2008 <2.0 1200 <2.0 <2.0 NA #N/A 1st Qtr 3/11/2009 <1.0 1,100 <1.0 <1.0 64 11.6 2nd Qtr 6/23/2009 <10 1,200 <1.0 <1.0 62 9.8 3rd Qtr 9/14/2009 <1.0 910 <1.0 <1.0 51 8.1 4th Qtr 12/22/2009 <1.0 300 <1,0 <1.0 1st Qtr 3/3/2010 <1.0 460 <1.0 <1.0 46 .5.0 2nd Qtr 6/14/2010 <1.0 220 <1.0 <1.0 42 1.6 3rd Qtr 8/12/2010 <1.0 100 <1.0 <1.0 38 0.8 4th Qtr 10/15/2010 <1.0 1 100 <1 0 <1.0 52 11.0 1st Qtr 2/23/2011 <1.0 620 <1.0 <1.0 32 976 2nd Qtr 6/14/2011 <1.0 280 <1.0 <1.0 42 3.3 3rd Qtr 8/17/2011 <1.0 180 <1.0 <1.0 41 1.9 4th Qtr 11/16/2011 <1.0 110 <1.0 <1.0 45 1.1 TiftliFifY 1/19/2012 <1.0 76 <1.0 <1.0 40 0.9 2nd Qtr 6/14/2012 <1.0 79 <1.0 <1.0 46 0.6 3rd Qtr 9/12/2012 <1.0 130 <1.0 <1.0 44 1.0 4th Qtr 10/3/2012 <1.0 140 <1.0 <1.0 45 1.6 1st Qtr 2/13/2013 <1.0 154 <1.0 <1.0 49.1 1.2 2nd Qtr 6/13/2013 <1.0 486 <1.0 <1.0 51.5 5.6 3rd Qtr 9/12/2013 <1.0 1,126 <1.0 <1.0 67.9 13.0 4th Qtr 11/14/2013 <1.0 1 380 <1.0 <1.0 7.9:9. _ ._ ........... ______16.0 1st Qtr 1/29/2014 5.16 1,260 <1.0 <1.0 .1.678. 2nd Qtr 5/23/2014 <1.0 1,110 <1.0 <1.0 77.3 13.9 3rd Qtr 8/27/2014 <1.0 1,060 1.5 <1.0 74 9.8 41h Qtr 10/30/2014 <1.0 1 220 <1 0 <1.0 75.2 13.2 1st Qtr 3/18/2015 <1.0 1,210 <1.0 <1.0 78.6 15.0 2nd Qtr 6/11/2015 <1.0 1,240 <1.0 <1.0 75 11.4 3rd Qtr 9/10/2015 <1.0 1,280 <1.0 <1.0 89.5 14.0 4th Qtr 10/29/2015 <1 0 1,350 <1.0 <1 0 79 9 - 13.5 1st Qtr 3/22/2016 <1.0 1,430 <1.0 <1.0 84.1 17.3 2nd Qtr 6/8/2016 <1.0 1,510 <1.0 <1.0 89.5 14.9 3rd Qtr 8/4/2016 <1.0 1,500 <1.0 <1.0 85.3 14.9 4th Qtr 10/26/2016 <1.0 1,290 <1.0 <1.0 84.4 14.8 lst Qtr 3/21/2017 <1.0 1,260 <1.0 <1.0 74.6 13.0 2nd Qtr 6/21/2017 <1.0 1,140 <1,0 <1.0 73.1 13.0 3rd Qtr 8/4/2017 <1.0 1,320 <1.0 <1.0 77 13.4 4th Qtr 10/11/2017 <1.0 1,150 <1.0 <1.0 70 12.9
DWMRC..a,dq.F1a919... <9.5 1 100 <15 16 J M 13.0 1st Qtr 3/21/2018 <1.0 1,240 <1.0 <1.0 72.7 11.1 2nd Qtr 6/14/2018 <1.0 914 <1.0 <1.0 64.5 11.2 3rd Qtr 9/6/2018 <1.0 911 <1.0 <1.0 75.5 10.1 41h Qtr 12/13/2018 <1.0 Igo <1.0 <1.0 63.5 10.6, 1st Qtr 3/20/2019 <1.0 8e8 <1.0 <1.0 59.3 0.34 2nd Qtr 6/19/2019 <1.0 799 <1.0 <1.0 58.7 8.86 3rd Qtr 9/12/2019 <1.0 734 <1.0 <1.0 55.8 7.79 4th Qtr 12/18/2019 <1.0 768 <1.0 <1.0 62 6.89 1st Qtr 3/18/2020 <1.0 798 <1.0 <1.0 53.5 7.83 2nd Qtr 6/11/2020 <1.0 928 <1.0 <1.0 60.1 8.13 3rd Qtr 9/19/2020 <1.0 854 <1.0 <1.0 53.9 7.34 r 11/11/2020 41 tsht QQ t rt <1.0 903 <1.0 <1.0 58.6 8.69 3/18/2020 <1.0 718 <1.0 <1.0 58.1 7.20
(1) As of March 2012 both north and south meld life ponds 110 10, jer recervirj water NA and #N/A(for graphs) = not analyzed Shaded indicates concentrations exceeding GWQS. J = Approximate value
TABLE 1 (14 of 31) Historic Summary Of Monitoring Well Analytical Results Up To The 1st Qarter 2021
Chloroform Contamination Investigation DUSA White Mesa Mill
TW4-11 W.-dorm purnp, ,..i Umfertelan5)
Sampling Event
Parameter
(GWQS) Carbon Tetrachloride
(5 pg/L)
Chloroform
(70 pg/L)
Chloromethane
(30 pg/L)
Methylene Chloride
(5 pg/L)
Chloride
No GWQS (mg/L)
Nitrate, Nitrate + Nitrite
(10 mgIL) 1st Qtr 3/16/2005 NA 4,400 NA NA NA 8.7
2nd Qtr 5/25/2005 NA 3,590 NA NA NA 10.3 3rd Qtr 8/31/2005 <10 4,400 <10 </0 NA 9 4 415 Qtr 12/7/2005 <100 _4_,40..0 <100 </00 58 9.4
1st Qtr 3/9/2006 <50 4,400 <50 <50 56 9.2 2nd Qtr 6/14/2006 <50 4,300 <50 <50 56 10.0
3rd Qtr 7/20/2006 <50 4,080 <50 <50 55 10.0 1.7 3 660 2.7 1.3 55 10.0 i st Qtr ' 2/26./2067 1.3 3,600 <1.0 1.6 54 10.1
2nd QV 6/27/2007 1.6 3,800 <1.0 . <1.0 53 10.6 3rd Qtr 8/15/2007 1.7 4,500 <1.0 <1.0 53 10.2 41h Qtr 10/10/2007 1.6 .4„400 <1.0 1.2 53 9.8 1st Qtr 3/28/2008 <1.0 iio <1.0 <1.0 63 7.7
2nd Qtr 6/25/2008 <1.0 640 <1.0 <1.0 46 7.3
3rd Qtr 9/10/2008 <1.0 900 <1.0 <1.0 42 7.9 4th Qtr 10/15/2008 NA #N/A NA NA 47 9.5 11/18/2008 <2.0 1 000 <2 0 <2.0 NA #N/A 1st Qtr 3/11/2009 <1.0 1,000 <1.0 <1.0 49 7.3
2nd QV 6/23/2009 <1.0 . 980 <1.0 <1.0 44 6.8 3rd Qtr 9/14/2009 <1.0 1,000 <1.0 <1.0 49 7.0 4th Qtr 12/22/2009 <1.0 860 <1.0 <1.0 46 6S 1st Qtr 3/3/2010 <1.0 820 <1.0 <1.0 42 6.8
2nd Qtr 6/14/2010 . <1.0 820 <1.0 <1.0 40 6.9 3rd Qtr 8/12/2010 <1.0 800 <1.0 <1.0 43 6.7 4th Qtr 10/15/2010 <1.0 720 <1.0 <1.0 49 6.4 151 Qtr 2/23/2011 <1.0 1,000 <1.0 <1.0 46 6.5 2nd Qtr 6/1/2011 <1.0 930 <1.0 <1.0 49 7.3
3rd Qtr 8/17/2011 <1.0 820 <1.0 <1.0 48 7.1
41h Qtr 11/16/2011 <1.0 1500 <1.0 <1.0 46 7.1 1 ifeltiTTE 1/24/2012 <1.0 610 <1.0 <1.0 43 6.8
2nd Qtr 6/13/2012 <1.0 660 <1.0 <1.0 52 6.7
3rd Qtr 9/13/2012 <1.0 740 <1.0 <1.0 49 3.0
41h Qtr 10/3/2012 <1.0 730 <1.0 <1.0 50 7.0 1st Qtr 2/13/2013 3.23 867 <1.0 <1.0 47.3 6.8 2nd Qtr 6/18/2013. <1.0 788 <1.0 <1.0 49.3 7.4
3r0 Qtr 9/12/2013 <1.0 865 <1.0 <1.0 46.6 7.8
41h Qtr 11/13/2013 <1.0 874 <1.0 <1.0 46.7 1st Qtr 2/5/2014 5.19 785 <1.0 <1.0 48.5 47
88..01
2nd Qtr 5/23/2014 <1.0 751 <1.0 <1.0 51.6 6.92 3rd Qtr 8/27/2014 <1.0 719 1.2 <1.0 48 5.4 4th Qtr 10/29/2014 <1.0 803 <1.0 <1.0 56.4 . 7.33
1sadr(2) 3/9/2013 1.24 2,450 <1.0 <1.0 49.8 8.72 2nd Qtr 6/11/2015 <1.0 2,710 <1.0 <1.0 62.2 8.48 3r0 Qtr 8/31r2015 <1.0 1,120 <1.0 <1.0 73.1 9.61
4th Qtr 10/29/2015 <1.0 2,730 <1.0 <1.0 55.3 7 5 1st Qtr 3/9/2016 1.2 2,660 <1.0 <1.0 55.5 7.13 2nd Qtr 5/23/2016 2.19 3,340 <1.0 <1.0 56.4 7.81 3rd Qtr 7/25/2016 <1.0 3,200 <1.0 <1.0 55.3 8.83
41h Qtr 10/12/2016 <1.0 ,Ago <16 <1.0 57.2 8.92
1st Qtr 3/8/2017 1.71 3,310 <1.0 <1.0 49.8 8.12 2nd Qtr 6/13/2017 1.83 3,370 <1.0 <1.0 51.4 7.92 3rd Qtr 7/26/2017 1.81 3,290 <1.0 <1.0 51 7.78
415 cly._ 10/11/2017 1.48 2,880 2.900 <1.0 <1.0 49.7 7.79
DW.MRDmitiarmte st Qtr . 3/12/2018 <38 1.82 <60 <1.0 <1.0 140 .1 .......:.F._ ......._........ ...8i: 3,090 nd Qtr 1.34 2,800 <1.0 <1.0 52.4 7.51 rd Qtr 8/22/2018 1.47 3,050 <1.0 <1.0 53.3 7.15
1 33 2,030 .... ... <1.0 <1.0 45.4 .85
Q
11/28/2018
11 ; Qtrt 3/8/2019 1.48 2,820 <1.0 <1.0 46.8 7.50 nd Qtr 6/5/2019. 1.52 2,970 1.4 <1.0 45.3 8.30 rd Qtr 9/4/2019 th Qtr 12/18/2019 <1.0 1.47 , 2,790 Ago <1.0 <1.0 <1.0 <1.0 48.8 49.0 7.15 7.14 st Qtr 2/19/2020 <1.0 2,990 <1.0 <1.0 51.9 7.07
nd QV 5/11/2020 1.37 2,810 <1.0 <1.0 48.6 7.56
rd Qtr 9/4/2020 1.47 3,070 <1.0 <1.0 46.3 7.59 th Qtr isg61 010 <1.0 „6 ;/2 3.86 <1.0 43.3 ; .29 '( - iitiii,""". 2/23/2021 Zi76----- 2.750 <1.0 <1.0 49.5
(1) As of March 2012 both north nd south eald lrlit po o o ger renewing water
212hkeototrn al111p111LWIII started 1/14/15
NA = not analyzed Bold and italics indicates the MDI_ exceeded the GWQS.
Bold and italics indicates the MDL exceeded the GWQS. J = Apprommated value
TABLE 1 (15 of 31) Historic Summary Of Moriitoring Well Analytical Results Up To The 1st Qarter 2021
Chloroform Contamination Investigation
DUSA White Mesa Mill
TW4-12 Sampling Event Parameter _,
(GWQS)
Carbon Tetrachloride (5 pg/L) Chloroform (70 pg1L) Chloromethane (30 pg/L) Methylene Chloride (5 pg/L) Chloride
No GWQS (mg/L)
Nitrate, Nitrate -i- Nitrite (10 mg/L)
1st Qtr 3/16/2005 NA 01.0 NA NA NA 1.4 2nd Qtr 5/25/2005 NA <1.0 NA NA NA 1.6 3rd Qtr 8/31/2005 01.0 <1.0 5.8 <1.0 NA 1.5 4th Qtr 12/7/2005 <1.0 <1.0 1.0 <1.0 19 1 4
1 st Qtr 3/9/2006 <1.0 <1.0 2.6 <1.0 19 1.3 2nd Qtr 6/14/2006 <1.0 <1.0 1.4 <1.0 16 14 3rd Qtr 7/20/2006 <1.0 <1.0 1.4 <1.0 16 1 4 4th Qtr 11/8/2006 <1.0 <1.0 <1.0 <1.0 ......__ 15 _____..... ____. .... 1 4 .._ ... 1st Qtr 2/28/2007 <1.0 <1.0 <1.0 <1.0 16 1.5
2nd Qtr 6/27/2007 <1.0 <1.0 <1.0 <1.0 18 1.5 3rd Qtr 8/15/2007 <1.0 <1.0 <1.0 <1.0 29 1.4 41h Qtr 10/10/2007 <1.0 <1.0 01.0 <1.0 .....16 1 .1.4. l st Qtr 3/28/2008 <1.0 <1.0 <1.0 <1.0 1.6 2nd Qtr 6/25/2008 <1.0 <1.0 <1.0 <1.0 19 2.7 3rd Qtr 9/10/2008 <1.0 <1.0 <1.0 <1.0 18 2.7 !sgigtr........... 10/15/2008 <1.0 <1.0 <1.0 <1.0 22 2.5 ist atr 3/11/2009 <1.0 <1.0 <1.0 <1.0 23 2.4 2nd Qtr 6/23/2009 <1.0 <1.0 <1.0 <1.0 22 3.8 3rd Qtr 9/14/2009 <1.0 <1.0 <1.0 <1.0 22 5.1 4th Qtr 12/16/2009 <1.0 <1.0 <1.0 <1.0 23 3.6 1st Qtr 2/23/2010 <1.0 <1.0 <1.0 <1.0 22 4.0 2nd Qtr 6/14/2010 <1.0 <1.0 <1.0 <1.0 29 11.0
3rd Qtr 8/10/2010 <1.0 <1.0 <1.0 <1.0 35 9.0 4th Qtr 10/15/2010 <1.0 <1.0 <1.0 <1.0 31 8.0 1st Qtr 2/15/2011 <1.0 <1.0 <1.0 <1.0 31 6.5 2nd Qtr 5/25/2011 <1.0 <1.0 <1.0 <1.0 32 7.0 3rd Qtr 8/16/2011 <1.0 <1.0 <1.0 <1.0 31 6.8 4th Qtr 11/15/2011 <1.0 <1.0 <1.0 <1.0 30 8.0 1ifDtr (1) 1/17/2012 <1 0 <1.0 <1 0 <1.0 28 _ 7.7
2nd Qtr 5/31/2012 <1.0 01.0 <1.0 <1.0 34 10.0
3rd Qtr 8/29/2012 <1.0 <1.0 <1.0 <1.0 39 13.0 4th Qtr 10/3/2012 <1.0 <1.0 <1.0 <1.0 39 13.0 1st Qtr 2/13/2013 01.0 <1.0 <1.0 <1.0 36.7 --.121.6 2nd Qtr 5/29/2013 <1.0 <1.0 <1.0 <1.0 38.6 14.2
3rd Qtr 8/29/2013 <1.0 <1.0 <1.0 <1.0 41.7 17.4 41h Qtr 11/6/2013 <1.0 <1.0 <1.0 <1.0 41.4 16.4 1st Qtr 1/22/2014 <1.0 <1.0 <1.0 <1.0 41.6 18.4 2nd Qtr 5/21/2014 <1.0 <1.0 <1.0 <1.0 40.2 17.0 3rd Qtr 8/27/2014 01.0 <1.0 <1.0 <1.0 47 13.0
4th Qtr 10/23/2014 <1.0 <1.0 <1.0 <1.0 50.2 16.1 1st Qtr 3/11/2015 <1.0 <1.0 <1.0 <1.0 50.6 19.2 2nd Qtr 6/10/2015 <1.0 <1.0 <1.0 <1.0 56 18.8 3rd Qtr 9/2/2015 <1.0 <1.0 <1.0 <1.0 60.2 164 4t6 Mr 10/21/2015 <1.0
<1.0
<1.0
<1.0
<1.0
<1 0
<1.0
<1.0
51
51.3
18.0
TW4" D1 s'Iiatrte 3/15/2016 <1.0 <1.0 <1.0 <1.0 56.2 318:08 4
2nd Qtr 5/25/2016 <1.0 <1.0 <1.0 01.0 66.4 30.7 Dep.. TWI-t 5)25/7016 <1.0 <1.0 <1.0 <1.0 67 113.0 3rd Qtr 7/27/2016 <1.0 <1.0 <1.0 <1.0 67.5 37.7
10/12/2016 <1.0 <1.0 <1.0 <1.0 72.6 25.8 41 t
sht 0Q tt rr 3/14/2017 <1.0 <1.0 <1.0 <1.0 62.6 25.9 2nd Qtr 6/14/2017 <1.0 1.25 <1.0 <1.0 67.2 29.9 3rd Qtr 8/2/2017 <1.0 1.2 <1.0 <1.0 65.3 25.1 Deplicate TW4.70 4th Qtr 10/10/2017
<1.0
<1.0 <1111:090
<1.0 <1.0 <1.0 <1.0 67
56.2
26.7 26.9
TW4-70 <1.0 <10 <1.0 61A .2.6.:.5. Dl :riga 3/14/2018 <1.0 <1.0 <1.0 <1.0 ..§-..§ i 9. 2nd Qtr 6/12/2018 <1.0 <1.0 <1.0 <1.0 53.6 18.4 3rd Qtr 8/29/2018 <1.0 <1.0 <1.0 <1.0 59.9 13.6
415 Qtr 11/30/2018 <1.0 <1.0 <1.0 <1.0 56.1 104
1st Qtr 3/16/2019 <1.0 <1.0 <1.0 <1.0 50.8 10.1
2nd Qtr 6/13/2019 <1.0 <1.0 <1.0 <1.0 55.3 8.31 3rd Qtr 9/11/2019 <1.0 <1.0 <1.0 <1.0 52.6 5.58 41h Qtr 12/14/2019 <1.0 <1.0 <1.0 <1.0 58.0 8.04 1st Qtr 3/17/2020 <1.0 <1.0 <1.0 <1.0 53.0 6.39
2nd Qtr 6/11/2020 <1.0 <1.0 <1.0 <1.0 51.7 4.95
3rd Qtr 9117/2020 <1.0 <1.0 01.0 <1.0 50.3 2.34 <1.0 <1.0 <1.0 <1.0 48.0 5.91

th CIt 11/4/2020 41st

Ctrr 3/17/2021 <1.0 01.0 <1.0 <1.0 52.0 3.10
(1) As of Mar, 2012 both north and south wad lrfeunds no lo recenau water NA = not analyzed Shaded indicates concentrations exceeding GWC1S.
TABLE 1 (16 of 31) Historic Summary Of Monitoring Well Analytical Results Up To The 1st Qarter 2021
Chloroform Contamination Investigation
DUSA White Mesa Mill
1W4-13
Sampling Event
Parameter
(GWQS)
Carbon Tetrachloride
(5 paiL) Chloroform
(70 pg/L)
Chloromethane
(30 pg/L)
Methylene Chloride
(5 pg/L)
Chloride
No GWQS (mg/L)
Nitrate, Nitrate + Nitrite
(10 mg/L)
1st Qtr 3/16/2005 NA <1.0 NA NA NA
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2nd Qtr 5/25/2005 NA <1.0 NA NA NA
3rd Qtr 8/31/2005 <1.0 <1.0 3.1 <1.0 NA
4th Qtr 12/7/2005 01.0 <1.0 <1.0 <1.0 69
1st Qtr 3/9/2006 <1.0 <1.0 1.7 <1.0 67
2nd Qtr 6/14/2006 <1.0 <1.0 1.4 <1.0 66 3rd Qtr 7/20/2006 <1.0 <1.0 <1.0 <1.0 65
41h Qtr 11/8/2006 <1.0 <1.0 <1.0 <1.0 33
1st Qtr 2/28/2007 <1.0 01.0 <1.0 <1.0 59
2nd Qtr 6/27/2007 <1.0 <1.0 <In <1.0 59
3rd Qtr. 8/15/2007 01.0 <1.0 <1.0 <1.0 58 4th Qtr 10/10/2007 01.0 <1.0 <1.0
1st Qtr 3/28/2008 <1.0 <1.0 <1.0 <1.0 54
2nd Qtr 6/25/2008 <1.0 <1.0 <1.0 <1.0 58
3rd Qtr 9/10/2008 <1.0 <1.0 <1.0 <1.0 50 4th Qtr 10/15/2008 <1.0 <1.0 <1.0 <1.0 58
1st Qtr 3/4/2009 <1.0 <1.0 <1.0 <1.0 58
2nd Qtr 6/23/2009 <1.0 <1.0 <1.0 <1.0 57
3rd Qtr 9/14/2009 <1.0 <1.0 <1.0 <1.0 63
41h Qtr 12/16/2009 <1.0 <1.0 <1.0 <1.0 60
1st Qtr 2/24/2010 <1.0 <1.0 <1.0 <1.0 53
2nd Qtr 6/14/2010 <1.0 <1.0 <1.0 <1.0 53
3rd Qtr 8/10/2010 <1.0 <1.0 <1.0 <1.0 55
41h Qtr 10/15/2010 <1.0 <1.0 <1.0 <1.0 55
1st Qtr 2/15/2011 <1.0 <1.0 <1.0 <1.0 60
2nd Qtr 5/25/2011 <1.0 <1.0 <1.0 <1.0 56
3rd Qtr 8/16/2011 <1.0 <1.0 <1.0 <1.0 60
4th Qtr 11/15/2011 <1.0 <1.0 <1.0 <1.0 ..M fit-MITT 1/17/2012 01.0 <1.0 <1.0 <1.0 55
2nd Qtr 5/31/2012 <1.0 <1.0 <1.0 <1.0 59
3rd Qtr 8/29/2012 <1.0 <1.0 <1.0 01.0 60
4th Qtr 10/3/2012 <1.0 <1.0 <1.0 <1.0 60
1st Qtr 2/13/2013 <1.0 <1.0 <1.0 <1.0 59.3 2nd Qtr 5/29/2013 <1.0 <1.0 <1.0 <1.0 56 3rd Qtr 8/29/2013 <1.0 <1.0 <1.0 <1.0 63.5
4th Qtr 11/6/2013 <1.0 <1.0 <1.0 <1.0 58.5
1st Qtr 1/22/2014 <1.0 <1.0 <1.0 01.0 63.1
2nd Qtr 5/21/2014 <1.0 <1.0 <1.0 <1.0 56.1
3rd Qtr 8/23/2014 <1.0 <1.0 <1.0 <1.0 62
4th Qtr 10/23/2014 <1.0 <1.0 <1.0 <1.0 66.1
1st Qtr 3/11/2015 <1.0 <1.0 <1.0 <1.0 66.4
2nd Qtr 6/10/2015 <1.0 <1.0 <1.0 <1.0 70.3
3rd at 9/2/2015 <1.0 <1.0 <1.0 <1.0 76.5
4th Qtr 10/21/2015 <1.0 <1.0 <1.0 <1.0 65.5 1st Qtr -3/16/2016 <1.0 <1.0 <1.0 <1,0 69.4 7.97
2nd Qtr 5/25/2016 <1.0 <1.0 <1.0 <1.0 71.8 5.87
3rd Qtr 7/28/2016 <1.0 <1.0 <1.0 <1.0 69.3 6.14
4th Qtr 10/19/2016 <1.0 <1.0 <1.0 <1.0 70.9 6 20
1st Qtr 3/16/2017 <1.0 <1.0. <1.0 <1.0 66.0 6.05
2nd Qtr 6/15/2017 <1.0 <1.0 <1.0 <1.0 70.4 6.49
3rd Qtr 8/2/2017 <1.0 <1.0 <1.0 <1.0 70.5 6.15
4th Qtr 10/10/2017 <1.0 <1.0 <1.0 <1.0 60.9
65i7
17
1st Qtr 3/14/2018 <1.0 <1.0 <1.0 <1.0 71.0 6
2nd Qtr 6/12/2018 <1.0 <1.0 <1.0 <1.0 65.0 6/4
3rd Qtr 8/29/2018 <1.0 <1.0 <1.0 <1.0 73.7 5.13
11/30/2018 <1 0 <1.0 <1.0 <1 0 64.5 41 t
s
h
t
QQ
t
t
r
r
3/16/2019 <1.0 <1.0 <1.0 <1.0 61.6
5 .29 5.74
2nd Qtr 6/13/209 ,, <1.0 <1.0 <1.0 <1.0 65.4 6.56
3rd Qtr 9/11/2019 <1.0 <1.0 <1.0 <1.0 65.3 5.19
12/14/2019 <1.0 <1.0 <1 0 <10 68.7 5.17 41 t
s
h
t

Q
C1
t
trr
3/17/2020 <1.0 <1.0 <1.0 <1.0 63.9 5.5
2nd Qtr 6/11/2020 <1.0 <1.0 <1.0 <1.0 62.7 9.0
3rd Qtr 9/17/2020 <1.0 <1.0 <1.0 <1.0 60.2 5.25
481 Qtr 11/4/2020 <1.0 <1.0 <1.0 <1.0 60.6 4.92
st Qtr 3/17/2021 <1.0 <1.0 <1.0 <1.0 67.3 5.57
;1iAsvfMxivh2O.,v'.iivv..i,v.mfepOrWf101o 2.?r recemr.22 wat r
NA= not analyzed Shaded indicates concentrations exceeding GWQS
TABLE 1 (17 of 31) Historic Summary Of Monitoring Well Analytical Results Up To The 1st Qarter 2021
Chloroform Contamination Investigation DUSA White Mesa Mill
TW4-14
Sampling Event
Parameter
(GWQS)
Carbon Tetrachloride
(5 pg/L)
Chloroform
(70 pg/L)
Chloromethane
(30 pg/L)
Methylene Chloride
(5 pg/L) Chloride
No GWQS (mg/L)
Nitrate, Nitrate + Nitrite
(10 mg/L)
)st Qtr , 3/16/2005 NS NS NS NS NS NS 2nd Qtr 5/25/2005 NS NS NS NS NS NS 3rd Qtr 8/31/2005 NS NS NS NS NS NS 41 tsht Q ttrr
Q
12/7/2005 3/9/2006 NS NS NS
NS
NS
NS
NS
NS
NS
NS
NS
NS 2nd Qtr. . 6/14/2006 NS NS NS NS NS NS 3rd Qtr 7/20/2006 NS NS NS Ns NS NS 4th Qtr 11/8/2006 <1.0 NS <1.0 37 .... ..?.:1 1st Qtr 2nd Qtr 3rd Qtr
2/28/2007 6/27/2007
8/15/2007
<1.0 <1.0
<1.0
<1.0 <1.0
<1.0
<1.0
<1.0 .,
<<111
.
..000 <1.0 <1.0
<1.0
38
38 36
2..3
1.4 1.1 tsht 1 c a
Q t rt 10/10/2007 <1.0 <1.0 4 r <1.0 0.8 3/28/2008 <1.0 <1.0 <1.0 <1.0 -17 0.4 2nd Qtr 6/25/2008 <1.0 <1.0 <1.0 <1.0 35 1.6 3rd Qtr 9/10/2008 <1.0 <1.0 <1.0 <1.0 34 1.38 4th Qtr 10/15/2008 <1.0 <1.0 <1.0 <1.0 40 0.76 1st Qtr 3/4/2009 <1.0 <1.0 <1.0 <1.0 35 1.6 2nd Qtr 6/23/2009 <1.0 <1.0 <1.0 <1.0 36 1.4 3rd Qtr 9/14/2009 <1.0 <1.0 <1.0 <1.0 38 1.5 41h Qtr 12J16/2009 <1.0 <1.0 <1.0 <1.0 .,..._ 34 1.4 1st Qtr 3/23/2010 <1.0 <1.0 <1.0 <1.0 33 2.5 2nd Qtr 6/14/2010 <1.0 <1.0 <1.0 <1.0 49 2.9 3rd Qtr 8/10/2010 <1.0 <1.0 <1.0 <1.0 35 2.8 41h Qtr 10/15/2010 <1.0 <1.0 <1.0 <1.0 29 2.9 1st Qtr 2/15/2011 <1.0 <1.0 <1.0 <1.0 25 1.8 2nd QV 6/24/2011 <1.0 <1.0 <1.0 <1.0 24 1.4 3rd Qtr 8/16/2011 <1.0 <1.0 <1.0 <1.0 33 2.6 4th Qtr 1/15/2011 <1 .0 <1.0 <1.0 <1.0 15 1.7
lifaiFTI) 1/17/2012 <1.0 <1.0 <1.0 <1.0 20 1.9
2nd Qtr 6/14/2012 <1.0 <1.0 <1.0 <1.0 35 3.3
.3rd Qtr 8/29/2012 <1.0 <1.0 <1.0 . <1.0 37 3.9 '4th Qtr 10/3/2012 <1.0 <1.0 <1.0 ....1.:0 . 37 ..3;.9. 1st Qtr 2/7/2013 <1.0 <1.0 <1.0 <1.0 3.5.2 4.6 2nd Qtr 5/29/2013 <1.0 <1.0 <1.0 <1.0 38.6 4.4 3rd Qtr 8/29/2013 <1.0 <1.0 <1.0 <1.0 37.6 4.51 4th Qtr 11/6/2013 <1.0 <1.0 <1.0 <1.0 36.5 4.81 1st Qtr 1/22/2014 <16 <1.0 <1.0 <1.0 35.5 5.92 2nd Qtr 5/21/2014 <1.0 <1.0 <1.0 <1.0 32.5 487 3rd Qtr 8/13/2014 <1.0 <1.0 <1.0 38 4.1 41h Qtr 10/23/2014 <1.0 <1.0 <1.0 <1.0 38.9 5.22 1st Qtr 3/12/2015 <1.0 1.7 <1.0 <1.0 40.1 5.22
2nd Qtr 6/10/2015 <1.0 1.82 <1.0 <1.0 41.8 3.55 3rd Qtr 913/2015 <1.0 <1.0 <1.0 <1.0 42.4 2.77 4th Qtr_.... ....... 10/23/2015 <is 1.46 <1.0 <1,0 40.6 2.45 'i iibtr 3/16&016 "<.1 .0 4.49 <1.0 -riii- 42.4 2.94 2nd Qtr 5/26/2016 <1.0 6.15 <1.0 3.18 43.6 2.45 3rd Qtr 8/3/2016 <1.0 5 <1.0 1.8 42.4 2.88 4th Qtr 10/20/2016 <1.0 7.02 <1.0 1.59 45.6 2.86 1st Qtr 3/15/2017 <1.0 6.45 <1,,0 2.18 45.4 4.36 2nd Qtr 6/15/2017 <1.0 6.85 <1,0 <1.0 46.9 5.12 3rd Qtr 8/2/2017 <1.0 6.14 :41.0 <1.0 46.4 4.84 41h Qtr 10/10/2017 <1.0 6.13 <1.0 <1.0 42.5 4.73
1st Qtr 3/15/2018 <1.0 5.8 <1.0 2.18 51.5 5.67 2nd Qtr 6/13/2018 <1.0 5.12 <1.0 <1.0 46.9 6.36 3rd Qtr 8/30/2018 <1.0 4.76 <1.0 <1.0 54.1 5.34 41h Qtr 12/12/2018 <1.0 4,41 <1.0 <1.0 48.7 5.85
1st Qtr <1.0 4.08 <1.0 <1.0 48.7 6.16 2nd Qtr 6/13/2019 <1.0 4.18 <1.0 <1.0 48.3 5.86 3rd Qtr 9/11/2019 <1.0 6.08 <1.0 <1.0 45.4 4.77 41h Qtr 12/14/2019 <1.0 3.83 <1.0 <1.0 49.4 1st Q tr 3/17/2020 <1.0 2.98 <1.0 <1.0 48.4 46.
.7
176 2nd Qtr 6/11/2020 <1.0 2.87 <1.0 <1.0 47.6 6.57
3rd Qtr 9/18/2020 <1.0 2.41 <1.0 <1.0 45.1 5.57
41thst QQttrr
11/4/2020
3/18/2021
<1.0
<1.0 2.69 1.77 <1.0 <1.0 <1.0 <1.0 49.7 48.2 5.81 5.56
(1) As of March 2017 both north and south veld bfe yds no lo or recessu water
NS = not sarnpled Shaded indicates concentrations exceeding GWQS.
TABLE 1 (18 of 31)
Historic Summary Of Monitoring Web Analytical Results Up To Theist Qarter 2021 Chloroform Contamination Investigation
DUSA White Mesa Mill
TW4-16 Samphng Event Parameter (GWQS)
Carbon Tetrachloride (5 pg/L) Chloroform (70 pg/L) Chloromethane (30 pg/L) Methylene Chloride
(5 pg11...)
Chloride
No GWQS (mg/L)
Nitrate, Nitrate + Nitrite
(10 mg/L) 1st Qtr 3/16/2005 NA 240 NA NA NA
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2nd Qtr 5/25/2005 NA 212 NA NA NA 3rd Qtr 8/31/2005 <1.0 85 3.2 43 NA 41h Qtr 12/7/2005 <1.0 14 2.6 5.9 64 1st Qtr 3/9/2006 <1.0 3 9 1.1 21 60 2nd Qtr 6/14/2006 <1.0 13 2.4 8.9 55 3rd Qtr 7/20/2006 <1.0 5.2 <1.0 2.7 60 4th Qtr 11/8/2006 <1.0 13.6 <1.0 9.2 62 1st Qtr 2/28/2007 <1.0 8.7 <1.0 6.6 79 2nd Qtr 6/27/2007 <1.0 2.6 <1.0 1.8 75 3rd Qtr 8/15/2007 <1.0 7.1 <1.0 5.1 65 4th Qtr 10/10/2007 <1.0 1.4 <1.0 1 69 1st Qtr 3/28/2008 <1.0 11 <1.0 26 52 2nd Qtr 6/25/2008 <1.0 <1.0 <1.0 <1.0 58 3rd Qtr 9/10/2008 <1.0 10 <1.0 14 71 41h Qtr 10/15/2008 <1.0 3.9 <1.0 6.6 89 .... ............. 1st Qtr 3/4/2009 <1.0 <1.0 <1.0 <1.0 73 2nd Qtr 6/23/2009 <1.0 <1.0 <1.0 <1.0 76 3rd Qtr 9/14/2009 <1.0 <1.0 <1.0 <1.0 79 4th Qtr 12/17/2009 <1.0 <1.0 <1.0 <1.0 76 1st Qtr 3/24/2010 <1.0 <1.0 <1.0 <1.0 77 2nd Qtr 6/14/2010 <1.0 2.1 <1.0 <1.0 64 3rd Qtr 8/24/2010 <1.0 4.3 <1.0 <1.0 72 4th Qtr 10/15/2010 <1.0 3 <1.0 <1.0 71 1 st Qtr 2/22/2011 <1.0 15 <1.0 <1.0 86 2nd Qtr 5/26/2011 <1.0 16 <1.0 <1.0 81 3rd Qtr 8/17/2011 <1.0 9.2 <1.0 <1.0 63 4th Qtr 11/16/2011 NA NA NA NA 38 (I )... 12/7/2011 <1.0 <1.0 <1.0 1.4 NA 1i1:4ir (3) 1/18/212 <1.0 <1.0 <1.0 1.7 48 2nd Qtr 5/26/2012 <1.0 <1.0 <1.0 <1.0 53 3rd Qtr 8/30/2012 <1.0 <1.0 <1.0 <1.0 59 4th Qtr 10/3/2012 <1.0 <1.0 <1.0 <1.0 59 1st Qtr 2/7/2013 <1.0 <1.0 <1.0 <1.0 58.1 2nd Qtr 5/30/2013 <1.0 <1.0 <1.0 4.21 49.8 3rd Qtr 9/5/2013 <1.0 <1.0 <1.0 <1.0 54.4 4th Qtr 11/7/2013 <1.0 13.4 <1.0 <1.0 56.6 1st Qtr 1/29/2014 <1.0 6.93 <1.0 <1.0 66.8 2nd Qtr 5/22/2014 <1.0 14.6 <1.0 <1.0 80.7 3rd Qtr (2) 8/14/2014 <1.0 229 <1.0 <1.0 80 3rd Qtr 9/24/2014 <1.0 371 <1.0 <1.0 NA 4th Qtr 10/29/2014 <1.0 387 <1.0 <1.0 92.1 lat Qtr 3/12/2015 <1.0 153 <1.0 <1.0 65 2nd Qtr 6/11/2015 <1,0 65.3 <1.0 <1.0 61 3rd Qtr 9/3/2015 <1.0 82 <1.0 <1.0 65.8 4gLgy......... wools .1.2... 112 <1.0 <1 0 58.3 - '1st Qtr 3/17/2016 <1.0 45.9 <1.0 <1.0 56.5 2nd Qtr 5/26/2016 <1.0 93.4 <1.0 <1.0 61.3 3rd Qtr 8/3/2016 <1.0 49 <1.0 <1.0 60 4th Qtr 10/26/2016 <1.0 92.9 <1.0 <1.0 66.7 1st Qtr 3116/2017 <1.0 19.1 <1.0 <1.0 62.2 2nd Qtr 6/20/2017 <1.0 64.3 <1.0 <1.0 60.6 3rd Qtr 8/3/2017 <1.0 143 <1.0 <1.0 67.1 4th Qtr 10/11/2017 <1.0 98 <1.0 <1.0 54.2 DWMRC aptt sample 92 <1.5 1.9 J 64 1st Mr - '.-- "-3/20/2018 <1.0 170 <1.0 <1.0 85.1
Duplicate TW4-75 <1.0 171 <1.0 <1.0 84.7 2nd Qtr 6/14/2018 <1.0 54.5 <1.0 <1.0 62.5 3rd Qtr 8/30/2018 <1.0 54.5 <1.0 <1.0 73 41h Qtr 12/12/2018 <1.0 52.0 <1.0 <1,0 68.8 1st Qtr 3/19/2019 <1.0 60.6 <1.0 <1.0 66.3 2nd Qtr 6/19/2019 <1.0 76.2 <1.0 <1.0 71.5 3rd Qtr 9/12J2019 <1.0 99.8 <1.0 <1.0 72.9 4t1n Qtr 12/14/2019 <1.0 94.3 <1.0 <1.0 88.6 Duptdate TA/(-75 <1.0 91.0 <1.0 <1.0 84.1 lit Qir 3/18/2020 <1.0 113 <1.0 <1.0 76.2 2nd Qtr 6/12J2020 <1.0 141 <1.0 <1.0 79.7 3rd Qtr 9/19/2020 <1.0 220 <1.0 <1.0 77.4 41h Qtr 11/11/2020 <1.0 270 <1.0 <1.0 85.9 Duplicate TW4-75 <1.0 277 <1.0 <1.0 85.6
DWMRC split sarbple <10 290 <20 <20 87.0 ' 1st Qtr 3/24/2021 <1.0 248 <1 0 <1.0 92.6
s were resampled because Iuboratory mussed holding time. (2) VOCs were resampled 131 As of March 2012 both north and south wuri ilfy ponds no longer receiving water
NA = not analyzed
Shaded Mdicates concentrations exceeding GWQS. J = Approximate value
H = Sample was analyzed beyond holding tmes and may not be accureate concentration.
TABLE 1 (19 of 31)
Historic Summary Of Monitoring Well Analytical Results Up To The 1st Qarter 2021 Chloroform Contamination Investigation
DUSA White Mesa Mill
TW4-18 Sampling Event Parameter
(GWQS) Carbon Tetrachloride
(5 pgIL)
Chloroform
(70 pg/L)
Chloromethane
(30 pg/L)
Methylene Chloride
(5 pg/L) Chloride No GWQS (mg/L) Nitrate, Nitrate . Nitrite (10 mg/L) 1st Qtr 3/16/2005 NA 38 NA NA NA 14.1 2nd Qtr 5/25/2005 NA 29.8 NA NA NA 12.9 3rd Qtr 8/31/2005 <1.0 39 2.8 01.0 NA 13.3 41h Qtr 12/7/2005 <1.0 14 1.1 <1.0 41 7.3 1st Qtr 3/9/2006 <1.0 12 1.6 <1.0 36 5.9 2nd Qtr 6/14/2006 <1.0 12 2,.7 <1.0 35 4.7 3rd Qtr 7/20/2006 <1.0 10.8 <1.0 <1.0 35 6.1 4th Qtr 11/8/2006 <1.0 12.5 <1.0 <1.0 34 5.7 1st QV 2/28/2007 <1.0 9.2 <1.0 <1.0 30 ......f 2nd Qtr 6/27/2007 <1.0 8 <1.0 <1.0 28 4.9 3rd Qtr 8/15/2007 <1.0 8.9 <1.0 <1.0 32 5.0 ,

41 t
s
ht Q tr 10/10/2007

Q8. 3/28/2008 <1.0 <1.0 7.4 6.4 < i .0 <1.0 <1.0 <1.0 27 23 44
0.7 2nd Qtr 6/25/2008 <1.0 5.7 <1.0 <1.0 23 46 3rd Qtr 9/10/2008 <1.0 8 <1.0 <1.0 26 4.9 41h Qtr 10/15/2008 <1.0 9.4 <1.0 <1 0 . 30 .§.1 1st Qtr 3/4/2009 <1.0 11 <1.0 <1.0 29 5.2 2nd Qtr 6/23/2009 <1.0 16 <1.0 <1.0 30 6.2 3rd Qtr 9/14/2009 <1.0 13 <1.0 <1.0 26 5.9 4th Qtr 12/17/2009 <10 8.2 <1.0 <1.0 30 5.4 1st Qtr 3/2412010 <lb 69 <lb <lb 41 5.1 2nd Qtr 6/14/2010 <1.0 29 <1.0, <1.0 35 9.0 3rd Qtr 8/12/2010 <1.0 29 <1.0 <to. 37 9.0

r 10/15/2010

41 tsht Q ttr 2/22/2011 a <1.0 <1.0 30 39 <1.0 <1.0 <1.0 <1.0 50
52 10.0 To-.6 2nd Qtr 5/26/2011 <1.0 26 <1.0 <1.0 36 9.0 3rd Qtr 8/17/2011 <1.0 29 < to <1.0 23 4.6 4th Qtr 11/16/2011 NA NA NA NA 23 6.3

8 ) 12/7/2011

l'ifQ.E. ) 1/18/2012 <1.0 <1.0 28 25 <1.0 <1.0 <1.0 <1.0 NA 18 NA
_ 4.4 2nd Qtr 6/13/2012 <1.0 24 <1.0 <1.0 30 66- 3rd Otr 9/11/2012 <1.0 38 <1.0 <1.0 26 6.6 4th Otr 10/3/2012 <1.0 30 <1.0 <1,0 27 1st Qtr 2/13/2013 <1.0 34.9 <1.0 <1.0 23.1 ---.§51 2nd Qtr 6/13/2013 <1.0 37.9 <1.0 <1.0 22.9 8.9 3rd Qtr 9/5/2013 <1.0 41 <1.0 <1.0 36.2 12.1 4th Qtr 11/13/2013 <1.0 44.3 <1.0 <1.0 37.1 14.2 1st Qtr 1/30/2014 <1.0 6.93 <1.0 <1.0 38.9 12.8 2nd Qtr 5/22/2014 <1.0 6.93 <1.0 <1.0 47 12.2 3rd Qtr 8/14/2014 <1.0 32.8 <1.0 <1,0 49 9.8 41h Qtr 10/28/2014 <1.0 33 <1.0 <1.0 40.8 11.1 1st Qtr 3/12/2015 <1.0 32 <1.0 <1.0 41.6 11.7 2nd Qtr 6/11/2015 <1.0 30.5 <1.0 <1.0 43.5 9.69 3rd Qtr 9/3/2015 <1.0 28.7 <1.0 <1.0 47.6 15.7 4th Qtr 10/28/2015 <1.0 52.9 <1.0 <1 0 6 24 <1.0 ----- ------- -3904 4.7 1st Qtr 3/17/2016 56.6 <1.0 <1.0 5.96 2nd Qtr 6/8/2016 <1.0 60 <1.0 <1.0 43.8 5.45 3rd Qtr 8/3/2016 <1.0 56.3 <1.0 <1.0 40.7 5/9

r 10/26/2016

4
114
ht QQtt
r

3/16/2017 <1.0 <1.0 60.1 62 <1.0 <1.0 <1.0 <1.0 43.9 ............,... 39:4 . - ... .1 ‘1 47 Duplicate TW4-75 <1.0 61.5 <1.0 <1,0 41.1 4.41 2nd Qtr 6/20/2017 <1.0 63.8 <1.0 <1.0 41.6 4.50 3rd Qtr 8/3/2017 <1.0 62.8 <1.0 <1.0 40.4 4.24 Duplicate1W4-75 <1.0 62.3 <1.0 <1,0 41.5 4.31 41h Qtr 10/11/2017 <1.0 62.9 <1.0 <1.0 37.1 4.43 1st Qtr 3/15/2018 <1.0 62.3 <1.0 <1.0 44.3 4.32 2nd Qtr 6/13/2018 <1.0 59.9 <1.0 <1.0 39.5 4.09 3rd Qtr 8/30/2018 <1.0 56.2 <1.0 <1.0 45.6 3.51 4th Qtr 12/13/2018 <1.0 57.6 <1.0 <1.0 38.2 3.60 1st Car 3/19/2019 <1.0 52.8 <1,0 <1.0 37.6 3.85 2nd Qtr 6/19/2019 <1.0 54.2 <1.0 <1.0 39.5 4.01 Duplicate TW4-75 <1.0 54.4 <1.0 <1.0 40.8 2.95 3rd Otr 9/11/2019 <1.0 56.2 <1.0 <1.0 36.8 3.25 41h Qtr 12/18/2019 <1.0 62.0 <1.0 <1.0 42.7 3.02 lst Qtr 3/18/2020 <1.0 57.0 <1.0 <1.0 39.4 3.71 2nd Qtr 6/12/2020 <1.0 58.2 <1.0 <1.0 41.4 3.62 3rd Qtr 9/18/2020 <1.0 60.0 <1.0 <1.0 38.7 3.36 4th Qtr 11/11/2020 <1.0 58.6 <1.0 <1.0 39.6 3.67 DWMRC spyt sample <10 56.0 <20 :210 0 0 3.30 1st Qtr 3/18/2021 <1.0 52.0 <1b 4411..8 3.61 - -" -- were resampteri bacauSe aboratoly m560d 5Va1n9 sme. (2) As of March 2012 both north and south wild life ponds no longer receiving water.
NA = not analyzed Shaded indicates concentrabons exceeding GWQS.
TABLE 1 (20 of 31) Historic Summary Of Monitoring Well Analytical Results Up To The 1st Qarter 2021
Chloroform Contamination Investigation DUSA White Mesa Mill
TW4-19 (chlorofrorn pumping well started 4/30/031
Sampling Event
Parameter
(GWQS)
_
Carbon Tetrachloride (5 pg/L) Chloroform
(70 pg/L)
Chloromethane
(30 pgIL) Methylene Chloride (5 pg/L) Chloride No GWOS (mgIL) Nitrate, Nitrate .. Nitrite (10 mg/L) 1st Qtr 3/16/2005 NA 2,200 NA NA NA 5.3 2nd Qtr 5/25/2005 NA 1,200 NA NA NA 5.7 3rd Qtr 8/31/2005 <5.0 1,400 <5.0 <5.0 NA 4.6 41h Qtr 12/7/2005 <50 2 800 <50 <50 81 <0.1 1st Qtr 3/9/2006 <50 1,200 <50 <50 86 4 2nd Qtr 6/14/2006 <50 1,100 <50 <50 116 5.2 3rd Qtr 7/20/2006 <50 1,120 <50 <50 123 4.3 4th Qtr 11/8/2006 1.6 1 050 2.6 <1.0 134 4.6 1st Qtr 2/28/2007 1.3 1,2-00 <1.0 <1.0 133 4 2nd Qtr 6/27/2007 Did not sarnple 3rd Qtr 8/15/2007 1.9 1,100 <1.0 <1.0 129 4.1 4th Qtr 10/10/2007 1.9 1190 <1-0 <1.0 132 4 1st Qtr 3/28/2008 2.9 1,800 <1.0 <1.0 111. 2.2 2nd Qtr 6/25/2008 <1.0 1,000 <1.0 <1.0 128 2.8 3ni Qtr 9/10/2008 8.6 3,600 <1.0 <1.0 113 35.2 401 Qtr 10/15/2008 12 4200 <1.0 <1.0 124 47.8 1st Qtr 3/4/2009 1.2 1,100 <1.0 <1.0 127 32 2nd Qtr 6/23/2009 1.2 990 <1.0 <1.0 132 2.4 3rd Qtr 9/14/2009 15 6,600 <1.0 <1.0 43 <0.1 th Qtr 12/22/2009 16 .4.,700 <1.0 <1.0 .114 26,7. 1st Qtr 2/17/2010 1.3 940 <1.0 <1.0 144 2 nd Qtr 6/14/2010 4.2 1,800 <1.0 <1.0 132 4.4 3rd Qtr 8/16/2010 4.9 2,000 <1.0 <1.0 142 5.9 th Qtr 10/15/2010 1.3 1200 <1.0 <1.0 146 .. .2,7. 17 st Qtr 2/17/2011 3,400 <16 <16 135 .176 nd Qtr 6/7/2011 8.3 4,000 <1.0 <1.0 148 12.0 3rd Qtr 8/17/2011 2.1 970 <1.0 <1.0 148 3.0 4th Qtr 11/16/2011 148 5.0 12/5/2011 5.4 2 200 <1.0 <1.0 ............. . 1st Qtr Y 1/23/2012 1 5 650 <1.0 <1.0 138 0.6 2nd Qtr 6/6/2012 1.1 460 <1.0 <1.0 149 - 2.4. 3rd Qtr 9/4/2012 3.5 950 <1.0 <1,0 149 2.5 41h Qtr 10/3/2012 1500 <1.0 <1.0 1st Qtr 2/13/2013 4 5.15 4,210 <1.0 <1.0 i 64 8.0 2nd Qtr 6/5/2013 5.15 2,070 <1.0 <1.0 148 3.0 3rd Qtr 9/3/2013 20.7 8,100 <1.0 <1.0 179 17.6 4th Qtr 10/29/2013 6.42 942 <1.0 <1.0 4.7 1st Qtr 1/27/2014 4.05 586 <1.0 <1.0 1 34 134 1.6 2nd Qtr 5/19/2014 5.51 810 <1.0 <1.0 152 1.3 3rd Qtr 8/11/2014 1.9 1,410 8.3 <1.0 140 1.6 4t5 Qtr 10/21/2014 4.8 .4210 <1.0 <1.0 .1.30 4.7 1st Qtr 3/9/2015 8.92 4,660 <1.0 <1.0 336 8.56 2nd Qtr 6/8/2015 2.62 1,570 <1.0 <1.0 180 0.916 3rd Qtr 8/31/2015 <1.0 7,860 7.78 <1.0 326 11.6 4th Qtr 10/19/2015 12.2 784 5.46 <1.0 10.6 1st Qtr 3/9/2016 13.5 0 7,780 1.4 <1.0 2 52 276 15.70 2nd Qtr 5/26/2016 23.1 12,600 <1.0 <1.0 204 1.27 3rd Qtr 7/25/2016 9.89 6,040 <1,0 <1.0 214 10.5 4th Qtr 10/13/201.5,.. 10.8 .6,64.0 <1.0 <1.0 200 10.0 1st Qtr 3/8/2017 3.06 1,240 <1.0 <1.0 461 11.1 2nd Qtr 6/13/2017 1.35 510 <1.0 <1.0 135 0.243 3rd Qtr 7/26/2017 13.0 8,840 <1.0 <1.0 218 1.120 4th Qtr 10/11/2017 <1.0 129 <1.0 <1.0 139 0.377 1st Qtr 3/12/2018 1.36 2,640 <1.0 <1.0 193 8.6 2nd Qtr 6/8/2018 3.45 2,980 <1.0 <1.0 138 0.494 3rd Qtr 8/30/2018 2.03 1,910 <1.0 <1.0 166 2.55 4th Qtr 11/28/2018 6.18 5,270 <1.0 <1.0 1st Qtr 3/8/2019 2.43 2,050 <1.0 <1.0 ......Z ....9d3 i.
2nd Qtr 6/5/2019 15.9 11,500 <1.0 <1.0 160 8.96 3rd Qtr 9/4/2019 10.1 6,670 <1.0 <1.0 153 0.33 4th Qtr 12/10/2019 <1.0 551 <1.0 <1.0 147 0.535 1st Qtr 2/19/2020 13.7 8,720 5.41 <1.0 205 10.1 2nd Qtr 5/27/2020 10.4 7,600 <1.0 <1.0 147 1.14 3rd Qtr 9/4/2020 1.98 1,350 <1.0 <1.0 188 11.6 4th Chi' 10/28/2020 1.1 660 <1.0 <1.0 104 1.1 1st Chr 2/23/2021 8.4 6,660 5.41 <1.0 167 6,6
(2) As of March 2012 both north and south wild lrfe ponds no longer receiving water.
NA= not analyzed Bold and italics indicates the MDL exceeded the GWQS. Shaded indicates concentrations exceeding GWQS.
TABLE 1 (21 of 31) Historic Summary Of Monitoring Well Analytical Results Up To The 1st Qarter 2021 Chloroform Contamination Investigation
DUSA White Mesa Mill
TW4-20 (chlorofom pumping well started 8/4/051 Sarnpling Event
Parameter (GWQS)
Carbon Tetrachloride
(5 pg/L) Chloroform (70 pg/L) Chloromethane (30 pg/L) Methylene Chloride (5 pg/L) Chloride
No GWQS (mg/L)
Nitrate, Nitrate + Nitrite
(10 mg/L) 1st Qtr 3/16/2005 Monitor well was not installed 2nd Qtr (3) 5/25/2005 NA 39,000 NA NA NA 10.10 3rd Qtr 8/31/2005 <10 3,800 <10 <10 NA 2.90 th Qtr 12/7/2005 <250 19 090 <250 <250 131 1.80 1st Qtr 3/9/2006 <500 9200, <500 <500 120 3.80 2nd Qtr 6/14/2006 <500 61,000 <500 <500 235 9.40 3rd Qtr 7/20/2006 <1000 5,300 <1000 <1000 134 2.90 th Qtr 11/8/2006 7.1 ltpcio 1.9 2.2 124 3.50 st Qtr 2/26/2007 3.1 .4,450 <1.0 1.1 124 4.20 nd Qtr 6/27/2007 2.2 1,800 <1.0 <1.0 112 2.30 3rd Qtr 8/15/2007 3.5 5,200 <1.0 1.8 117 2.10 4th Qtr 10/10/2007 6.8 9 000 <1.0 1.9 170 5.60 1st Qtr 3/28/2008 9 13,000 <1.0 1.5 132 0.90 2nd Qtr 6/25/2008 13 30,000 <1.0 1.2 191 8.00 3rd Qtr 9/10/2008 15 21,000 <1.0 3.7 156 4.44 4th Qtr 10/15/2008 NA NA NA NA 168 5.51 1st Qtr 3/4/2009 5.7 8,200 <10 5.2 164 5.10 2nd Qtr 6/23/2009 4.9 6,800 <1 0 4.2 164 2.90 3rd Qtr 9/14/2009 8.4 13,000 <1.0 4.4 153 3.30 41h Qtr 12/22/2009 14 itpoo <1.0 3.0 187 5.30 15t Qtr 2/17/2010 2.7 3,550 <1.0 3.2 179 2.00 2nd Qtr 6/14/2010 11 18,000 <1.0 3.7 200 5.60 3rd Qtr 8/16/2010 12 15,000 <1.0 2.2 196 5.30 4th Qtr 10/15/2010 20 24 090 <1.0 5.5 203 4.60 1st Qtr 2/17/2011 27 31,003 <1.0 19.0 220 4.40 2nd Qtr 6/7/2011 10 8,100 <1.0 2.1 177 4.80 3rd Qtr 8/17/2011 7.3 3,800 <1.0 3.1 207 6.50 4th Qtr 11/16/2011 7.2 7 900 <1.0 2.5 186 4.20 fiftlii•py 1/23/2012 10 11,000 <1.0 1.3 207 7.90 2nd Qtr 6/6/2012 33 36,000 <1.0 <1.0 262 11.00 3rd Qtr 9/4/2012 28 13,000 <1.0 <1.0 289 10.80 4th Qtr 10/3/2012 22 11,000 <1.0 <1.0 302 11.00 1st Qtr 2/11/2013 19.6 18,500 <1.0 1.21 252 9.07 2nd Qtr 6/5/2013 32.5 26,300 <1.0 1.3 250 9.80 3rd Qtr 9/3/2013 25.7 26,800 <1.0 2.14 260 8.65 4th Qtr 10/29/2013 17.3 15,700 <1.0 1.37 272 9.64 ............. 1st Qtr 1/27/2014 18.4 17,800 <1.0 2.04 254 7.50 2nd Qtr 5/19/2014 22.1 22,100 2.31 3.98 269 5.95 3rd Qtr 8/11/2014 14.1 12,400 55.2 2.2 299 4.30 4th Qtr 10/21/2014 18.5 23,300 4.04 2.38 292 7.67 1st Qtr 3/9/2015 20.8 19,960 4.85 1.38 290 9.80 2nd Qtr 6/8/2015 16.2 17,600 13.4 1.73 296 5.76 3rd Qtr 8/31/2015 15.1 17,000 12.3 <1.0 365 9.3 4th Qtr 10/19/2015 14.5 17,000 10.8 1 293 6 23 1st Qtr 3/9/2016 20.2 21,600 4.09 1.16 293 10.30 2nd Qtr 5/23/2016 40.6 33,700 <1.0 <1.0 318 11.2 3rd Qtr 7/25/2016 26.6 23. 600 <1.0 <1.0 307 11.3 41h Qtr 10/12/2016 24.4 21 300 <1 0 <1 0 ..39.1 1st Qtr 3/8/2017 23.5 23,400 <1.0 <1.0 295 _. -1:121 2nd Qtr 6/13/2017 23.4 18,100 <1.0 <1.0 281 9.76 3rd Qtr 7/26(2017 25.0 27,600 1.25 <1.0 292 10.8 4th Qtr 10/12/2017 11.2 11,800 2.34 <1.0 293 8.91 1st Qtr 3/12/2018 15.9 15,60 1.77 2.36 289 9.5 2nd Qtr 6/14/2018 <1.0 12,000 <1.0 7.77 258 10.40 3rd Qtr 8/22/2018 9.85 10,500 4.98 <1.0 282 8.14 4th Qtr 11/28/2018 8.32 9,500 15.6 <1.0 295 ....PI?. 1st Qtr 3/8/2019 15.4 15,600 <1.0 <1.0 272 6.7 2nd Qtr 6/5/2019 10.1 13,700 <1.0 <1.0 279 9.59 3rd Qtr 9/4/2019 8.39 10,500 <1.0 <1.0 286 10.20 41h Qtr 12/10/2019 5.92 8290 2.67 <1.0 307 .......2,7§. 1 st Qtr 2/19/2020 8.6 i4,350 10.7 <1.0 310 9..81 2nd Qtr 5/27/2020 6.74 5 800 1.3 12.3 3.01 7.23 Well TW4-20 Abandoned in October 2020 1) VOCe were resampled because laboratory nosed holdmg tune. , As of March 2012 both north and south wild life ponds no longer receiving water.
2) Chloroform amminvell started 8/4/05. hIA = not analyzed Bold and italics indicates the MDL exceeded the GM& Shaded indicates concentrabons exceeding GWQS.
TABLE 1 (22 of 31) Historic Summary Of Monitoring Well Analytical Results Up To The 1st Qarter 2021
Chloroform Contamination Investigation
DUSA White Mesa Mill
TW4-21 (chloroform pumping well 6/9/15)
Sampling Event
Parameter
(GWQS)
Carbon Tetrachloride
(5 pg/L)
Chloroform
(70 pg/L)
Chloromethane
(30 pg/L) Methylene Chloride _5_p_g/L) Chloride No GWQS (mg/L) Nitrate, Nitrate -i- Nitrite (10 mg/L) 1st Qtr 3/16/2005 Monitor well was not installed 2nd Qtr 5/25/2005 NA 192 NA NA NA 14.6 3rd Qtr 8/31/2005 <5.0 78 <5.0 <5.0 NA 10.1 4th Qtr 12/7/2005 <1.0 86 <10 <1.0 ......P. ......2,6 1st Qtr 3/9/2006 <2.5 120 <2.5 <2.5 347 8..E 2nd Qtr 6/14/2006 <2.5 120 <2.5 <2.5 318 10.2 3rd Qtr 7/20/2006 <2.5 108 <2.5 <2.5 357 8.9 4th Qtr 11/8/2006 2 139 <1.0 <1.0 296 8.7 1st Qtr 2/28/2007 1.8 160 <1.0 <1.0 306 8.7 2nd Qtr 6/27/2007 5.8 300 <1.0 <1.0 327 8.6 3rd Qir 8/15/2007 <1.0 140 <1.0 <1.0 300 8.6 4th Qtr 10/10/2007 <1.0 120 <1.0 <1.0 288 1st Qtr 3/28/2008 7 390 <1.0 <1.0 331 ---1.N 2nd QV 6/25/2008 1.7 180 <1.0 <1.0 271 8.8 3rd Qtr 9/10/2008 1.6 120 <1.0 <1.0 244 7.57 41h Qtr 10/15/2008 NA #N/A NA NA 284 8.0 11/18/2008 2 170 <2.0 <2.0 NA #N/A 1st Qtr 3/11/2009 <1.0 180 <1.0 <1.0 279 8-.8 2nd Qtr 6/23/2009 <1.0 200 <1.0 <1.0 291 8.1 3rd Qtr 9/14/2009 <1.0 200 <1.0 <1.0 281 9.2 4th Qtr 12/22/2009 <1.0 160 <1 0 <1 0 256 _ 8 4

1st Qtr 2/25/201871TO . . 170 <1.0 <1.0 228 8.4 2nd Qtr 6/14/2010 <1.0 210 <1.0 <1.0 266 12.0 3rd Qtr 8/13/2010 9.2 390 <1.0 <1,0 , 278 14.0 41h Qtr 10/15/2010 1.2 200 <1.0 <1.0 _210 7 0 1st Qtr 2/22/2011 1.2 230 <1.0 <1.0 303 9.0 2nd Qtr 6/28/2011 4.8 290 <1.0 <1.0 290 12.0 3rd Qtr 8/17/2011 . 6.3 460 <1.0 <1.0 287 14.0 41h Qtr 11/16/2011 287 13.0 (11..._ 12/7/2011 6.7 390 <1Z <1.0 'rift* (2) 1/23/2012 6.4 420 <1.0 <1.0 228 15.0
2nd Qtr 6/6/2012 5.4 400 <1.0 <1.0 285 - 11.0 3rd Qtr 9/4/2012 6 410 <1.0 <1.0 142 13.0 7 390 <1.0 <1.0 411'; 10/3/2012._ QQ ttrr 2/11/2013 5.25 282 <1.0 <1.0 221 1-1.8 12nd Qtr 6/5/2013 3.49 328 <1.0 <1.0 243 13.8 . Qtr 9/3/2013 .3rd 2:13 244 <1.0 <1.0 207 10.3 '41h Qtr 10/29/2013 <1.0 204 <1.0 <1.0 206 9.0 . 1st Qtr 1/27/2014 6.23 220 <1.0 2.04 „ 200 11.4 2nd Qtr 5/19/2014 4.73 240 <1.0 2.04 243 11.5 3rd Qtr 8/11/2014 <1.0 204 <1.0 , <1.0 230 7.1 4th Qtr 10/21/2014 1.04 229 <1.0 <1.0 252 10.0 1st Qtr 3/9/2015 1.75 292 <1.0 <1.0 255 10.9 2nd Qtr (3) 6/8/2015 1.92 366 <1.0 <1.0 494 - 13.1
3rd Qtr 8/31/2015 <1.0 281 <1.0 <1.0 499 14.7 4th Qtr 10/19/2015 <1.0 339 <1.0 <1.0 413 14 3 1st Qtr 3/9/2016 <1.0 390 <1.0 <1.0 452 14.6 2nd Qtr 5/23/2016 <1.0 545 <1.0 „ <1 0 . 425 13.1 3rd Qtr 7/25/2016 <1.0 456 <1.0 <1.0 457 16.5 41h Qtr 10/12/2016 <1.0 456 01.0 <1.0 439 13.5 1st Qtr 3/8/2017 2.36 598 <1.0 <1.0 452 17.7 2nd Qtr 6/13/2017 1.16 224 <1.0 <1.0 309 9.53 3rd Qtr 7/26/2017 1.05 537 <1.0 <1.0 447 18.20 4th Qtr 10/11/2017 <1.0 466 <1.0 <1.0 378 16.90 DWMRC spillaampla <3.8 400 <6.0 14 .1 11 1st Qtr 3/12/2018 2.36 421 <1.0 <1.0 447 15.8 2nd Qtr 6/8/2018 <1.0 532 <1.0 <1.0 387 14.1 3rd Qtr 8/22/2018 <1.0 476 <1.0 <1.0 182 0.236 4th Qtr 10/22/2018 <1,0 585 <1.0 <1.0 392 15.2 1st Qtr 3/8/2019 <1.0 323 <1.0 <1.0 180 8.99 2nd Qtr 6/5/2019 <1.0 734 <1.0 <1.0 456 17,5 3rd Qtr 9/4/2019 <1.0 596 <1.0 <1.0 478 14.7 4th Qtr 12/10/2019 <1.0 794 <16 <1.0 339 5.73 1st Qtr 2/19/2020 01.0 844 2.58 .1.0 446 8.93
2nd Qtr 5/27/2020 <1.0 767 <1.0 <1.0 353 15.4 3rd Qtr 9/4/2020 . <1.0 920 <1.0 <1.0 382 12.6 41 tsht aQtrtr 10/28/2020 2/23/2021 <1.0 <1Z 948 400 <1.0 <1.0 <1, ° <1.0 454 411 16.3 15.20 (1) VOCs were resampled because laboratory mussed holchng time. 21 As ot March 2012 both north and south vole lde ponds no longer receivong water. Drciiio7ogrin pumping well stalled 6/9/15 NIA7.7c7Wtilyzed Shaded indicates concentrations exceedng GWQS. J = Approximated value
TABLE 1 (23 of 31)
Historic Summary Of Monitoring Well Analytical Results Up To The 1st Qarter 2021 Chloroform Contamination Investigation DUSA White Mesa Mill
TW4-22 (nitrate pumping well started 1/26(13) Sampling Event
Parameter
(GWQS)
Carbon Tetrachloride
(5 pg/L)
Chloroform
(70 pg/L)
Chloromethane
(30 pg/L)
Methylene Chloride
(5 pg/L) Chloride No GWQS (mg/L) Nitrate, Nitrate + Nitrite (10 mgIL) 1st Qtr 3/16/2005 Monitor well was not installed 2nd Qtr 5/25/2005 NA 340 NA NA NA 18.2 3rd Qtr 8/31/2005 <5.0 290 <5.0 <5.0 NA 15.7 41h Qtr 12/7/2005 <5.0 320 <5.0 <5.0 15.1 1st Qtr 3/9/2006 <10 390 <10 <10 2253 36 16.3 2nd Qtr 6/14/2006 <10 280 <10 <10 221 14.3 3rd Qtr 7/20/2006 <10 864 <10 <10 221 14.5 4th Qtr 11/8/2006 <1.0 350 1.6 <1.0 236 15.9 1st Qtr 2/28/2007 <1.0 440 <1.0 <1.0 347 20.9 2nd Qtr 6/27/2007 <1.0 740 <1.0 <1.0 273 19.3 3rd Qtr 8/15/2007 <1.0 530 <1.0 <1.0 259 19.3 4th Otr 10/10/2007 <1.0 440 <1.0 <1.0 238 .1,8. lst Qtr 3/28/2008 <1.0 1,400 <1.0 <1.0 519 .39.-1 2nd Qtr 6/25/2008 <1.0 1,200 <1.0 <1.0 271 41.9 3rd Qtr 9/10/2008 1.3 6,300 <1.0 <1.0 524 38.7 41h Qtr 10/15/2008 NA #N/A NA NA 539 36.3 11/18/2008 <2.0 630 <2.0 <2.0 NA #N/A ................ 1s1 Qtr 3/11/2009 <1.0 390 <1.0 <1.0 177 20.7 2nd Qtr 6/23/2009 <1.0 730 <1.0 <1.0 177 20.6 3rd Qtr 9/14/2009 <1.0 2,300 <1.0 <1.0 391 40.3 4th Qtr 12/29/2009 <1.0 380 <1.0 <1.0 175 17.8 1st Qtr 3/23/2010 <1.0 2,200 <1.0 <1.0 427 36.8 2nd QV 6/14/2010 <1.0 540 <1.0 <1.0 134 19.0 3rd Qtr 8/24/2010 <1.0 340 <1.0 <1.0 130 15.0 4th Qtr 10/15/2010 <1.0 340 <1.0 <1.0 134 16.0 1st Qtr 2/22/2011 1.2 1,300 <1.0 <1.0 114 18.0 2nd Qtr 6/1/2011 <1.0 210 <1.0 <1.0 138 17.0 3rd Qtr 8/17/2011 <1.0 450 <1.0 <1.0 120 15.0 416 Otr 11/16/2011 NA #N/A NA NA 174 19.0 (1).... 12/7/2011 <1.0 400 <1.0 <1.0 NA #N/A -171612'02 fifailify .1.0 200 <1.0 <1.0 36 14:6 2nd Qtr 6/13/2012 <1.0 120 <1.0 <1.0 35 12.5 3rd Qtr 9/12/2012 <1.0 121 <1.0 <1.0 , 7.0 4th Qtr 10/4/2012 <1.0 330 <1.0 <1.0 130 14.0 1s t dt r (-3) 2/11Z013 3.24 10,600 <1.0 <1.0 130" 58.0i 2nd Qtr 6/5)2013 3.35 12,500 <1.0 <1.0 586 50.2 3rd Qtr 9/3/2013 3.25 9,640 <1.0 <1.0 487 29.7 4th Qtr 10/29/2013 8.09 100 <1.0 <1.0 45.2 1st Qtr 1/27/2014 6.06 12,100 <1.0 2.83 5591 98 54.6 2nd Qtr 5/19/2014 6.65 12,400 <1.0 <1.0 614 47.2 3rd Qtr 8/11/2014 1.9 12,400 40 <1.0 540 41.5 41h Qtr 10/29/2014 3.32 1190 1.61 <1.0 54.9 1st Qtr 3/9/2015 3.77 12,700 4.31 <1.0 5956 67 69.2 2nd Otr 6/8/2015 2.42 8,050 3.42 <1.0 390 47.1 3rd Otr 8/31/2015 <1.0 7,810 5.47 <1.0 557 64.7 3.32 7 530 5.1 <1.0 567 56.1 1st Qtr 3/9/2016 <1.0 6,070 <1.0 <1.0 583 31.1 2nd Qtr 5/23/2016 2.64 8,570 <1.0 <1.0 598 58.4 3rd Qtr 7/25/2016 <1.0 5,840 <1.0 <1.0 619 61.3 4th Qtr 10/12/2016 1.08 3 370 <1 0 <1.0 588 61.5 1st Qtr 3/8/2017 1.56 5,320 <1.0 <1.0 566 69.8 2nd Qtr 6/13/2017 1.21 3,670 <1.0 <1.0 572 70.8 3rd Qtr 7/26/2017 <1.0 5,150 <1.0 <1.0 391 66.1 41h Qtr 10/11/2017 <1.0 4,770 <1.0 <1.0 600 80.1 DWMRC Vrisant.... <38 t.1.00 <60 150 J 610 79.0 1st Qtr 3/1212018 <1.0 4,530 <1.0 <1.0 607 62.3 2nd Qtr 6/8/2018 <1.0 3,010 <1.0 <1.0 580 72,5 3rd Qtr 8/22/2018 <1.0 3,600 <1.0 <1.0 613 55.4 41h Qtr 11/28/2018 01.0 ..1§80 <1.0 <1.0 567 76.7 1st Qtr 3/8/2019 1.02 4,310 <1.0 <1.0 528 71.9 2nd Qtr 6/5/2019 1.13 4,690 <1.0 <1.0 662 83.9 3rd Qtr 9/4/2019 <1.0 3,460 <1.0 <1.0 588 72.5 12/10/2019 41 t
sht <1.0 Aolp <1.0 <1.0 608 59.9 QQttrr 2/19/2020 1.02 3,910 <1.0 <1.0 606 57.7 2nd Qtr 5/27/2020 <1.0 2,530 <1.0 <1.0 578 60.5 3rd Qtr 9/4/2020 <1.0 3,760 <1.0 <1.0 514 64.8 4th Qtr 10/28/2020 6.83 1840 <1. <1.0 64.9 1st Qtr 2/23/2021 <i .0 5.100 .0 <1.0 52138 6 69.6
(1) VOCs were mewled because laboratory missed holding time. (2) As of March 2012 both north and south wild life ponds no longer receiving water.
12) Chloroform Eirnpnjwell started 1/26/13. NIA = not analyzed Shaded indicates concentrations exceeding GWCIS. Bold and italics indicates the MDL exceeded the GWOS. = APProximated value
TABLE 1 (24 of 31) Historic Summary Of Monitoring Well Analytical Results Up To The 1st Qarter 2021
Chloroform Contamination investigation DUSA White Mesa Mill
6— TW4-23 Sampling Event
Parameter
(GWQS)
Carbon Tetrachloride
(5 uctiL)
Chloroform (70 pg/L) Chloromethane (30 NIL) Methylene Chloride (5 pg/L) Chloride No GWQS (mg/L)
Nitrate, Nitrate + Nitrite
(10 mg/L)
2nd Otr 6/27/2007 <1 0 <1 0 <1 0 <1 0 47 <0 1
3rd Qtr 8/15/2007 <1 0 <1 0 <1 0 <1 0 46 <0 1 4th Qtr 10/10/2007 <1_0 <1 0 <1 0 <1 0 • 43 <0 1
1st Qtr 3/28/2008 <1 0 <1 0 <1 0 <1 0 41 <0 1
2nd Qtr 6/25/2008 <1 0 <1 0 <1 0 <1 0 41 <0 1
3rd Qtr 9/10/2008 <1 0 <1 0 <1 0 <1 0 35 <0 05 4th Qtr 10/15/2008 NA NA NA NA 51 <0 05 11/18/2008 <2 0 . <2 0 <2 0 • <2 0 ,NA NA
1st Qtr 3/4/2009 <1 0 <1 0 <1 0 <1 0 41 <0 1
2nd Qtr 6/23/2009, <1 0 <1 0 <1 0 <1 0 43 <0 1
3rd Qtr 9/14/2009 <1 0 <1 0 <1 0 <1 0 43 <0 1 4th Qtr 12/16/2009. <1 0 . <1 0 <1 0 <1 0 37 <0 1 1st Qtr 3/24/2010 <1 0 <1 0 <1 0 <1 0 45 <0 1
2nd Qtr 6/14/2010 <1 0 <1 0 <1 0 <1 0 40 <0 1
3rd Qtr 8/24/2010 <1 0 <1 0 <1 0 <1 0 40 <0 1 4th Qtr 10/15/2010 <1 0 . <1 0 <1 0 <1 0 34 <0 1 1st Qtr 2/16/2011 <1 0 <1 0 <1 0 <1 0 44 <0 1
2nd Qtr 6/14/2011 <1 0 <1 0 <1 0 <1 0 44 <0 1
3rd Qtr 8/16/2011 <1 0 <1 0 <1 0 <1 0 41 00 1
4th Qtr 11/15/2011 <1 0 <1 0 <1 0 <1 0 43 <0 1
1st Otr11 ) 1/17/2012 <1 0 <1 0 <1 0 <1 0 40 <0 1
2nd Qtr 5/31/2012 <1 0 <1 0 <1 0 <1 0 44 < 1
3rd Qtr 8/29/2012 <1 0 <1 0 <1 0 <1 0 46 <0 1 4th Qtr 10/3/2012 <1 0 0 <1 0 <1 0 45 <0 1 1st Qtr 2/7/2013 <1 0 11 0 <1 0 <1 0 43 6 <0 1
2nd Qtr 5/30/2013 <1 0 <1 0 <1 0 <1 0 44 7 0 1
3rd Qtr 9/5/2013 <1 0 <1 0 <1 0 <1 0 48 <0 1
4th Qtr 11/7/2013 <1 0 . <1 0 <1 0 <1 0 43 <0 1 1st Qtr 1/23/2014, <1 0 <1 0 <1 0 <1 0 44 6 <0 1
2nd Qtr 5/19/2014 <1 0 <1 0 <1 0 <1 0 42 3 <0 1
3rd Qtr 8/13/2014 <1 0 <1 0 <1 0 <1 0 46 <0 1
41h Qtr 10/28/2014 <1 0 . <1 0 <1 0 <1 0 46 8 <0 1
lst Qtr 3/12/2015 <1 0 <1 0 <1 0 <1 0 47 3 <0 1 2nd Qtr 6/8/2015 <1 0 <1 0 <1 0 <1 0 48 4 <0 1
3rd Qtr 9/3/2015 <1 0 <1 0 <1 0 <1 0 54 1 <0 1
4th Qtr 10/28/2015 <1 0 <1 0 <1 0 <1 0 46 4 <0 1
Duphcate 11Abit-70 <1 0 <1 0 <1 0 <1 0 • 46 4. <0 1 1st Qtr 3/16/2016 <1 0 <1 0 <1 0 <1 0 49 1 <0 1
2nd Qtr 5/26/2016 <1 0 <1 0 <1 0 <1 0 50 4 <0 1
3rd Qtr 8/23/2016 <1 0 <1 0 <1 0 <1 0 49 6 <0 1
Duplicate TW4-70 <1 0 <1 0 <1 0 <1 0 48 3 <0 1
Qtr 1.0/12/2016 <1.0 <1 0 <1 0 <1 0 • 52 1 <0 1
l
ath 1st Qtr 3/15/2017 <1 0 <1 0 <1 0 <1 0 47 7 <0 1
Duplicate 1W4-70 <1 0 <1 0 <1 0 <1 0 49 8 <0 1
2nd Qtr 6/15/2017 <1 0 <1 0 <1 0 <1 0 51 5 <0 1
3rd Qtr 8/2/2017, th Qtr 10/10/2017 <1 0 <1 0 <1 0 <1 0
<1 0
<2 0
<1 0
<2 0
51 8
44 7
<0 1
<0 1
QWMRC split sample <1 0 <1 0 <2 0 <2 0 52 <0 1 st Qtr 3/14/2018 <1 0 <1 0 <1 0 <1 0 53 8 <0 1
1
1
2nd Qtr 6/13/2018 <1 0 <1 0 <1 0 <1 0 47 6 <0 1
Duplicate1W4-70 <1 0 <1 0 <1 0 <1 0 47 9 <0 1
3rd Qtr 8/30/2018 <1 0 <1 0 <1 0 <1 0 56 <0 1
•4th Qtr 12/12/2018 <1 0 <1 0 <1 0 <1 0 54 9 <0 1 1st Qtr 3/16/2019 <1 0 <1 0 <1 0 <1 0 48 9 <0 1 2nd Qtr 6/13/2019 <1 0 <1 0 <1 0 <1 0 50 2 <0 1
3rd Qtr 9/11/2019 <1 0 <1 0 <1 0 <1 0 47 9 <0 1
4th Qtr 12/10/2019 <1 0 . _ <1 0 • <1 0 <1 0 54 4 <0 1
1st Qtr 3/17/2020 <1 0 <1 0 <1 0 <1 0 50 0 <0 1 2nd Qtr 6/11/2020 <1 0 <1 0 <1 0 <1 0 49 0 <0 1 3rd Qtr 9/17/2020 <1 0 <1 0 <1 0 <1 0 48 8 <0 1
4th Qtr 11/4/2020 <1 0 0 ..1 <1 0 <1 0 49 3 <0 1
1st Qtr 3/17/2021 <1 0 <1 0 <1 0 <1 0 51 6 <0 1
(1) As of March 2012 both north and south wild li recei NA - not analyzed Shaded indicates concentratons exceeding GWQS = Apprommated value
TABLE 1 (25 of 31)
Historic Summary Of Monitoring Well Analytical Results Up To The 1st Qarter 2021 Chloroform Contamination Investigation
DUSA White Mesa Mill
TW4-24 (nitrate pumping wet started 1/26/13)
Sampling Event
Parameter
(GWQS)
Carbon Tetrachloride (5 pg/L) Chloroform (70 pg/L) Chloromethane (30 pg/L) Methylene Chloride (5 pg/L) Chloride No GWQS (mg/L) Nitrate, Nitrate + Nitrite (10 mg/L)
2nd Qtr 6/27/2007 <1.0 2.6 <1.0 <1.0 770 26.1 3rd Qtr 8/15/2007 <1.0 2.2 <1.0 <1.0 791 29 4111..glr_ .1.gggg lst Qtr vi.,:.2... 1.5 1.5 <1.0 <1.0 <1.0 <1.0 692 740 ........24,7 24.4
2nd Qtr 6/25/2008 <1.0 1.4, <1.0 <1.0 834 45.3 3rd Qtr 9/10/2008 <1.0 2.9 <1.0 <1.0 1,180 38.4 41h Otr 10/15/2008 NA #N/A NA NA 1,130 44.8 11/18/2008 <2.0 <2.0 <2.0 <2.0 #N/A #N/A
1st Qtr 3/4/2009 <1.0 1.4 <1.0 <1.0 1,010 30.5. 2nd Qtr 6/23/2009 <1.0 1.5 <1.0 <1.0 759 30.4 3rd Qtr 9/14/2009 <1.0 1.4 <1.0 <1.0 618 30.7
41h Qtr 12/16/2009 <1.0 1.2 <1.0 <1.0 1,080 28.3
1st Qtr 3/25/2010 <1.0 1.3 <1.0 <1.0 896 33-..1.
2nd Qtr 6/14/2010 <1.0 1.7 <1.0 <1.0 639 30 3rd Qtr 8/24/2010 <1.0 1.8 <1.0 <1.0 587 31 4th Qtr 10/15/2010 <1.0 1.4 <1.0 <1.0 522 31
1st Qtr 2/16/2011 <1.0 1.8 <1.0 <1.0 1,100 31
2nd Qtr 6/14/2011 <1.0 1.1 <1.0 <1.0 1,110 35 3rd Qtr 8/16/2011 <1.0 1.7 <1.0 <1.0 967 34 41h Qtr 11/15/2011 NA #N/A NA NA 608 35
.(l). 12/7/2011 'fiftlif.(2) 1/16/2012
<1.0
<1.0
1.2 <1.0
<16
<1.0
<1.0
#N/A
373
#N/A .....
2nd Qtr 6/6/2012 <1.0 <1.0 <1.0 <1.0 355 - 37
3rd Qtr 8/30/2012 <1.0 <1.0 <1.0 <1.0 489 37
4th Mr 10/3/2012 <1.0 1 <1.0 <1.0 405 38 1st Qtr (3) 2/11/2013 <1.0 1 <1.0 <1.0 1 260 . 35.9
2nd Qtr 6/5/2013 <1.0 17.4 <1.0 <1.0 916 23.7 3rd Qtr 8/30/2013 <1.0 21.8 <1.0 <1.0 998 33
4th Qtr 10/29/2013 <1.0 32.5 <1.0 <1.0 1.030 35
1st Qtr 1/27/2014 1.18 786 <1.0 <1.0 809 --1176 2nd Qtr 5/19/2014 <1.0 62.7 <1.0 <1.0 1,020 35.0 3rd Qtr 8/11/2014 <1.0 76.3 <1.0 <1.0 1,150 31.5 4th Qtr 10/21/2014
1st Qtr 3/9/2015
<1.0
<1.0
25.8 49.2 <1.0 <1.0 <1.0 <1.0 .10.50 944 35.7 34.6
2nd Qtr 6/8/2015 <1.0 4.28 <1.0 <1.0 1,290 31.8 3rd Qtr 8/31/2015 <1.0 46.9 <1.0 <1.0 788 25.3 41h Qtr 10/19/2015 <1 0 25.3 <1.0 <1.0 909 29.6 1st Qtr 3/9/2016 <16 226 <16 <1.0 989 2 9.1
2nd Qtr 5/23/2016 <1.0 69.6 <1.0 <1.0 771 24.2
3rd Qtr 7/25/2016 <1.0 17.8 <1.0 <1.0 1,180 34.4
4th Qtr 10/12/2016 <1.0 20.8 <1.0 31.9 1st Qtr 3/8/2017 <1.0 18.3 <1.0 <<11.60 :14.900 41.3 2nd Qtr 6/13/2017 <1.0 17.2 <1.0 <1.0 1,080 39.9
3rd Qtr 7/26/2017 <1.0 17.8 <1.0 <1.0 1,230 40.0
4th Qtr 10/11/2017 <1.0 16.0 <1.0 <1.0 895 31.7
Ch/VMRC splft sample <0.38 36.0 <0.60 1.3 J 1,100 .......R0 . -3/16/2018 1st Qtr <1.0 24.9 <1.0 <1.0 1,320 44.9 2nd Qtr 6/14/2018 <1.0 49.2 <1.0 <1.0 792 33.6 3rd Qtr 8/22/2018 <1.0 35 <1.0 <1.0 996 33.8
4th Qtr 11/28/2018 <1.0 21 <1.0 <1.0 1,100 38.4
Ol swt MQRtrC """j 3/8/2019 <5 .0 <1.0
60
28.1
<5 .0
<1.0
<5.0
<1.0
1 000
1,040 39.3
2nd Qtr 6/5/2019 <1.0 28.8 <1.0 <1.0 1,020 33.2 3rd Qtr 9/4/2019 <1.0 31.1 <1.0 <1.0 1,130 36.4
4th Qtr 1st Qtr 122;1109;22002
190 <2 0 43.3 61.7 <1.0 <1.0 <1.0 <1.0 1,990 1,010 33.8 37.1
2nd Qtr 5/27/2020 <1.0 49.4 <1.0 <1.0 1,060 41.7
3rd Qtr 9/4/2020 <1.0 63.8 <1.0 <1.0 1,100 39.1
41h Qtr 10/28/2020 <1.0 72.6 <1.0 <1.0 1,050 35.9 1st Qtr 2/23/2021 <1.0 96.2 3.6 <1.0 1,170 41.9
(1) VOCs were resampled because laboratory missed holding hme. (2) As of March 2012 both north and south wild life ponds no longer receiving water.
2)Chloroforrn EimpinLwel) started 1/26/13 NA = not analyzed Shaded indicates concentrahons exceeding GWOS.
J = Approximated value
TABLE 1 (26 of 31)
Historic Summary Of Monitoring Well Analytical Results Up To The 1st Qarter 2021
Chloroform Contamination Investigation DUSA White Mesa Mill
TW4-25 (nitrate pumping well started 1/26/13)
Sampling Event
Parameter
(GWQS)
-Carbon Tetrachloride
(5 pg/L)
Chloroform
(70 pg11..)
Chloromethane
(30 pg/L)
Methylene Chloride
(5 pg/L)
Chloride
No GWQS (mg/L)
Nitrate, Nitrate + Nitrite
(10 mg/L)
2nd Qtr 6/27/2007 <1.0 <1.0 <1.0 <1.0 395 17.1
3rd Qtr 8/15/2007 <1.0 2.2 <1.0 <1.0 382 29
4th Qtr 10/10/2007 <1.0 <1.0 <1.0 <1.0 358 17
1st Qtr 3/28/2008 <1.0 <1.0 <1.0 <1.0 374 18.7
2nd Qtr 6/25/2008 <1.0 <1.0 <1.0 <1.0 344 22.1
3rd Qtr 9/10/2008 <1.0 <1.0 <1.0 <1.0 333 18.8
4th Qtr 10/15/2008 NA #N/A NA NA 366 21.3
11/18/2008 <2.0 <2.0 <2.0 <2,0 #N/A #N/A
1st Qtr 3/4/2009 <1.0 <1.0 <1.0 <1.0 3 15.3
2nd Qtr 6/23/2009 <1.0 <1.0 <1.0 <1.0 328 15.3
3rd Qtr 9/14/2009 <1.0 <1.0 <1.0 <1.0 328 3.3
12/16/2009 <1.0 <1.0 <1.0 .0
11.0 37 2961 - ..14...1 41 t ht s (I
Q tt
r
r
3/23/2010 <1.0 <1.0 <1.0 14.4
2nd Qtr 6/14/2010 <1.0 <1.0 <1.0 <1.0 306 16
3rd Qtr 8/10/2010 <1.0 <1.0 <1.0 <1.0 250 14 4th Qtr 10/15/2010 <1.0 <1.0 <1.0 , <1.0 2 15
1st Qtr 2/16/2 011 <1.0 1.8 <1.0 <1.0 5 15
2nd Qtr 5/25/2011 <1.0 <1.0 <1.0 <1.0 321 16
3rd Qtr 8/16/2011 <1.0 <1.0 <1.0 . <1.0 276 16
4th Qtr l'aftliFPI 11/15/2011
1/16/2012
<1.0
<1.0
<1.0
<1.0
<1.0 .
<1.0 ,
<1.0 <1.0 294 304 16 1.6.
2nd Qtr 5/31/2012 <1.0 <1.0 <1.0 <1.0 287 16
3rd Qtr 9/4/2012 <1.0 <1.0 <1 0 <1.0 334 17
4th Qtr 10/3/2012 <1 0 <1.0 <1 0 <1 0 338 17
1st Qtr (3) 2/11/2013 <1.0 <1.0 <1.0 <1.0 190' 9.04.
2nd Qtr 6/5/2013 <1.0 `,1 .0 . <1.0 <1.0 136 5.24
3rd Qtr 9/4/2013 <1.0 <1.0 <1.0 <1.0 119 5.69
4th Otr 10/31/2013 <1.0 <1.0 <1.0 <1.0 88.6 6.1
1st Qtr 1/27/2014 <1.0 <1.0 <1.0 <1.0 85.7 2.16
2nd Qtr 5/19/2014 <1.0 <1.0 <1.0 <1.0 51.1 1.21
3rd Qtr 8/11/2014 <1.0 <1.0 <1.0 <1.0 67 1.6
4th Qtr 10/21/2014 <1.0 <1.0 <1.0 <1.0 --.:,ili
1.03
1st Qtr 3/9/2015 <1.0 <1.0 <1.0 14.4
2nd Qtr 6/8/2015 <1.0 <1.0 <1.0 <1.0 58.3 1.14
3rd Qtr 8/31/2015 <1.0 <1.0 <1.0 <1.0 69.2 1.63 4t qtr..... l'stbir 10/19/2015 - --i§i01-6-7-1.6------ <1.0 <1.0 <1.0 <1 0 <1.0 .......... <1.0 93.7 62.7 _ 1 78
0.837 <1.0
2nd Qtr 5/23/2016 <1.0 <1.0 <1.0 <1.0 75.5 0.959
3rd Qtr 7/25/2016 <1.0 <1.0 <1.0 <1.0 74.1 1.78
r <1.0 <1.0 59.8 1.24 41 t
s
ht
QQ fr
t 10/31/25//22001167 <,11..00
7.11.50 <1.0 <1.0 285 17.0
2nd Qtr 6/13/2017 <1.0 <1.0 <1.0 <1.0 69.8 0.976
3rd Qtr 7/26/2017 <1.0 <1.0 <1.0 <1.0 70.1 1.23
4th Qtr 10/11/2017 <1.0 <1.0 <1.0 <1.0 68.0 1.29
1st Qtr 3/12/2018 <1.0 1.15 <1.0 <1.0 70.5 2.23
2nd Qtr 6(14/2018 <1.0 <1.0 <1.0 <1.0 60.3 1.14
3rd Qtr 8/22/2018 <1.0 <1.0 <1.0 <1.0 69.1 0.810
4th Qtr 11/28/2018 <1.0 <1.0 <1.0 <1.0 59.7 0.634
1s1 Qtr 3/8/2019 <1.0 <1.0 <1.0 <1.0 65 ---6:63.9
2nd Qtr 6/5/2019 <1.0 <1.0 <1.0 <1.0 59 0.821
3rd Qtr 9/4/2019 <1.0 <1.0 <1.0 <1.0 58.1 0.548
4th Qtr 1st Qtr 122//1190//22002190 :11..00 <1.0
<1.0 <1.0 <1.0
<1.0
<1.0
73.1
86.0
0.841
0.607
2nd Qtr 5/27/2020 <1.0 <1.0 <1.0 <1.0 76.8 0.851
3rd Qtr 9/4/2020 <1.0 <1.0 <1.0 <1.0 67.3 0.994
4th Qtr 10/28/2020 <1.0 <1.0 <1.0 <1.0 61.3 1.64
1st Qtr 2/23/2021 <1 0 <1.0 <1.0 <1.0 100 3.43
(1) VOCs were resampled because laboratory missed holding time. (2) As of March 2012 both north and south wild life ponds no longer receiving water.
2)Chloroform impinvell started 1/26/13
NA = not analyzed
Shaded indicates concentrations exceeding GWOS.
TABLE 1 (27 of 31)
Historic Summary Of Monitoring Well Analytical Results Up To The 1st Qarter 2021
Chloroform Contamination Investigation DUSA White Mesa Mill
TW4-26
Sampling Event
Parameter
(GWQS)
Carbon Tetrachloride
(5 pg/L)
Chloroform
(70 pg/L)
Chloromethane
(30 pg/L)
Methylene Chloride
(5 pg/L)
Chloride
No GWQS (mg/L)
Nitrate, Nitrate . Nitrite
(10 mg/L)
2nd Qtr 6/14/2010 01.0 13 <1.0 <1.0 33 7.9
3rd Qtr 8/24/2010 <1.0 5.2 <1.0 <1.0 17 9.0
41h Qtr 10/15/2010 <1.0 5.4 <1.0 <1.0 22 9.6
1st Qtr 2/16/2011 <1.0 2 <1.0 <1.0 30 10.0
2nd Qtr 5/26/2011 <1.0 2.9 <1.0 <1.0 15 10.0
3rd Cltr 8/17/2011 <1.0 2.8 <1.0 <1.0 19 11.0
4th Qtr 11/16/2011 NA #N/A NA NA 26 10.0
.(1) 12/7/2011 01.0 5.2 <1.0 <1.0 #N/A 8N/A
fi((2) 1/18/2012 <1.0 7 <1.0 <1.0 17 11.0
2nd Qtr 6/6/2012 <1.0 4.1 <1.0 <1.0 19
3rd Qtr 9/11/2012 <1.0 4.9 <1.0 <1.0 19 9.0
4th Qtr 10/3/2012 <1.0 4.9 <1.0 <1.0 19 12.0
1st Qtr 2/11/2013 <1.0 4.9 <1.0 <1.0 16.6 12.5
2nd Qtr 6/13/2013 <1.0 2.12 <1.0 <1.0 14.5 13.6
3rd Qtr 9/5/2013 <1.0 2.81 <1.0 <1.0 17.6 11.7
4th Qtr 11/7/2013 <1.0 3.37 <1.0 <1.0 .......... 15.9 .15.9
1st Qtr 1/29/2014 <1.0 1.43 <1.0 <1.0 16.9 7472
2nd Qtr 5/21/2014 <1.0 4.23 <1.0 <1.0 15.4 12.5
3rd Qtr 8/11/2014 <1.0 1.3 <1.0 <1.0 15 10.8
41h Qtr 10/28/2014 <1.0 2.45 <1.0 <1.0 14.6 12.3
1st Qtr 3/12/2015 <1.0 2.37 <1.0 <1.0 14.4 14.4
2nd Qtr 6/10/2015 <1.0 6.12 1.17 <1.0 14.4 11.3
3rd Qtr 9/3/2015 <1.0 4.77 <1.0 <1.0 14 14.2
4th QV 10/28/2015 <1.0 3.45 <1.0 <1.0 13 3 13.9
1st Qtr 3/16/2016 <1.0 1.8 <1.0 <1.0 13.7 16.9
2nd Qtr 5/26/2016 <1.0 8.23 <1.0 <1.0 15.2 13.9
3rd Qtr 8/3/2016 <1.0 4.42 <1.0 <1.0 13.9 17.9
41h Qtr 10/20/2016 <1.0 19.9 <1.0 <1.0 14.2 15.0
1st Qtr 3/16/2017 <1.0 46.1 <1.0 <1.0 16.2 15.8
2nd Qtr 6/20/2017 <1.0 244 <1.0 <1.0 19 15.2
3rd Qtr 8/3/2017 <1.0 419 <1.0 <1.0 25.8 15.2
41h Qtr 10/11/2017 <1.0 608 <1.0 <1.0 27.3 10.0
I st Qtr 3/21/2018 <1.0 1,050 <1.0 <1.0 35.5 12.2
2nd Qtr 6/14/2018 <1.0 960 <1.0 <1.0 33.5 13.2
3rd Qtr 9/6/2018 <1.0 916 <1.0 <1.0 38.9 13.5
4th Qtr 12/13/2018 <1.0 1 050 <1 0 <1.0 33.4 11.8
1st Qtr 3/20/2019 <1.0 96.3 <1.0 <1.0 32.9 12.2
2nd Qtr 6/5/2019 <1.0 1,070 <1.0 <1.0 35.8 12.6
3rd Qtr 9/12/2019 <1.0 877 <1.0 <1.0 32.0 10.9
4.1.t.,..Pg_... ....12061g21.9. .1:0 .107..,0 .5.1:9._. ' <1-0 38.3 10.3
1st Qtr 3/1812020 <1.0 1,090 <1.0 <1.0 36.3 'Itg
2nd Qtr 6/12/2020 <1.0 1,140 <1.0 <1.0 35.1 11.1
3rd Qtr 9/19/2020 <1.0 1120 <1.0 <1.0 34.8 10.5
11/11/2020 <1.0 1,160 <1.0 <1.0 36.3 11.9 41 t
s
ht
2tr
tr
3/24/2021 <1.0 1,030 <1 0 <1.0 38.9 11.3
TW4-27 Ilefati (2) 1/18/2012 <1.0 9 <1.0 <1.0 11 24.0
2nd Qtr 6/13/2012 <1.0 <1.0 <1.0 <1.0 17
3rd Qtr 9/4/2012 <1.0 <1.0 <1.0 <1.0 21 37.0
4th Qtr 10/3/2012 <1.0 <1.0 <1.0 <1.0 18 36.0
1st Qtr 2/7/2013 <1.0 <1.0 <1.0 <1.0 18.8 31.2
2nd Qtr 6/13/2013 <1.0 <1.0 <1.0 <1.0 20.3 29.4
3rd Qtr 8/30/2013 <1.0 <1.0 <1.0 <1.0 19 27.2
41h Qtr 11/6/2013 <1.0 <1.0 <1.0 <1.0 21.8 29.8
1st Qtr 1/23/2014 <1.0 <1.0 <1.0 <1.0 31.8 31.3
2nd Qtr 5/21/2014 <1.0 <1.0 <1.0 <1.0 20.6 31.1
3rd Qtr 8/13/2014 <1.0 <1.0 <1.0 <1.0 23 27.0
4th Qtr 10/28/2014 <1.0 <1.0 <1.0 <1.0 24.4 28.2
1st Qtr 3/11/2015 <1.0 <1.0 <1.0 <1.0 26.2 26.5
2nd Qtr 6/10/2015 <1.0 <1.0 <1.0 <1.0 26.8 24.0
3rd Qtr 9/2/2015 <1.0 1.3 <1.0 <1.0 26.8 20.9
41h Qtr 10/28/2015 <1.0 1.6 <1.0 <1.0 26.2 23.5
1st Qtr 3/16/2016 <1.0 2.11 <1.0 <1.0 28 25.0
2nd Qtr 5/26/2016 <1.0 3.16 <1.0 <1.0 21.2 28.7
3rd Qtr 8/3/2016 <1.0 2.78 <1.0 <1.0 27.1 21.8
4th Qtr 10/20/2016
1st Qtr 3/15/2017 <1.0 <1.0 3.8 4.33 <1.0 <1.0 :
11..00
2nd Qtr 6/15/2017 <1.0 5.65 <1.0 <1.0 27.9 23.8
3rd Qtr 8/2/2017 <1.0 6.05 <1.0 <1.0 29.5 20.0
41h Qtr 10/10/2017 <1.0 5.91 <1.0 <1.0 26.3 21.5
1st Qtr 3/14/2018 <1.0 6.95 <1.0 <1.0 30.3 19.5
2nd Qtr 6/13/2018 <1.0 5.95 <1.0 <1.0 28.3 22.0
3rd Qtr 8/30/2018 <1.0 7.35 <1.0 <1.0 31.4 18.1
4th Qtr 12/12/2018 <1.0 7.7 <1.0 <1.0 28.2 20.8
1st Qtr 3/16/2019 <1.0 6.54 <1.0 <1.0 26.2 21.5
2nd Qtr 6/13/2019 <1.0 8.24 <1.0 <1.0 28.6 22.3
3rd Qtr 9/11/2019 <1.0 7.58 <1.0 <1.0 25.3 21.2
41h Qtr 12/14/2019 <1.0 7.97 <1.0 <1.0 27.4 22.0
1st Qtr 3/18/2020 <1.0 8.04 <1.0 <1.0 27.6 23.6
2nd Qtr 6/11/2020 <1.0 7.92 <1.0 <1.0 28.0 21.5
3rd Qtr 9/18/2020 <1.0 5.62 <1.0 <1.0 26.2 25.2
4th Qtr 11/4/2020 <1.0 7.8 <1.0 <1.0 26.8 16.7
1st Qtr 3/18/2021 <1.0 4.66 <1.0 <1.0 27.5 23.0
(1) VOCs were resempled because laboratory missed holding Imre. ,2) As of March 2012 both north and south wild life ponds no longer . receiving water.
NA = not analyzed
Shaded indicates concentrations exceeding GWQS
TABLE 1 (28 of 31) Historic Summary Of Monitoring Well Analytical Results Up To The 1st Clarter 2021
Chloroform Contamination Investigation DUSA White Mesa Mill
TW4-28 Sampllng Event Parameter (GWQS)
Carbon Tetrachloride (5 pgIL) Chloroform (70 pg/L) Chloromethane (30 pg/L) Methylene Chloride (5 pg/L) Chloride No GWQS (mg/L) Nitrate, Nitrate + Nitrite (10 rng/L)
2nd Qtr 6/19/2013 <1.0 <1.0 <1.0 <1.0 44.6 14.9 3rd Qtr 8/29/2013 <1.0 <1.0 <1.0 <1.0 45.3 17.3

r 11/6/2013

41 tht QQtt
r

1/22/2014 s <1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
45.3
47,8 16.2 16.9 2nd Qtr, 5/21/2014 , <1.0 <1.0 <1.0 <1.0 45.7 16.5 3rd Qtr 8/13/2014 <1.0 <1.0 <1.0 <1.0 50 14.2 41h Qtr 10/23/2014 <1.0 <1.0 <1.0 <1.0 52.1 16.5
1st Qtr 3/11/2015 <1.0 <1.0 <1.0 <1.0 52.2 19.0 2nd Qtr 6/10/2015 <1.0 <1.0 <1.0 <1.0 564 19.0 3rd Qtr 9/2/2015 <1.0 <1.0 <1.0 <1.0 61.4 17.8 4th Qtr 10/21/2015 <1 0 <1.0 <1.0 <1.0 52.7 18.7
1st Qtr 3/15/2016 <1.0 <1.0 <1.0 <1.0 61.6 34.0 Duplicate TW4.65 <1.0 <1.0 <1.0 <1.0 61.4 32.6 2nd Qtr 5/25/2016 <1.0 <1.0 <1.0 <1.0 67.1 29.0 3rd Qtr 7/27/2016 <1.0 <1.0 <1.0 <1.0 70.1 31.3 Duplicate TW4-65 <1.0 <1.0 <1.0 01.0 70.9 35.6 4th Qtr 10/19/2016 <1.0 <1.0 <1.0 <1.0 70.9 25.5
lstQtr 3/14/2017 <1.0
<1.0
<1.0 <10 <1.0 <1 . 0 <1.0 73.7 64.2 25.4 24.4 Duphcate TW4.65 <1.0 <1.0 <1.0 <1.0 66.4 27,9 2nd Qtr 6/14/2017 <1.0 <1.0 <1.0 <1.0 68 6 26.0
3rd Qtr 7/27/2017 <1.0 <1.0 <1.0 <1.0 67.1 24.8 4th Qtr 10/10/2017 <1.0 <1.0 <1.0 <1.0 57.4 24.8 1st Qtr 3/14/2018 <1.0 „ . <1.0 <1.0 <1.0 65.0 17.2 2nd Qtr 6/12/2018 <1.0 <1.0 <1.0 <1.0 55.7 19.0 Dupficate TW4-65 <1.0 <1.0 <1.0 <1.0 56.7 18.7
3rd Qtr 8/29/2018 <1.0 <1.0 <1.0 <1.0 63.8 16.0,
4th Qtr 11/30/2018 <1.0 <1.0 <1.0 <1.0 52.4 17.7 1st Qtr 3/16/2019 . „ <1.0 . . . <1.0 <1.0 <1.0 51.7 17.2. 2nd Qtr 6/13/2019 <1.0 <1.0 <1.0 <1.0 51.8 15.0 3rd Qtr 9/11/2019 <1.0 , <1.0 <1,0 <1.0 49.0 10.2
4th Qtr 12/12/2019 <1.0 <1.0 <1.0 <1.0 50.0 9.48
1st Qtr 3/17/2020 <1.0 <1.0 <1.0 <1.0 52.1 9.87 2nd Qtr 6/10/2020 <1.0 <1.0 <1.0 . <1.0 49.8 9.55 3rd Qtr 9/17/2020 <1.0 <1.0 <1,.0 <1.0 47.4 8.36 4th Qtr 1st Qtr 31/11/47//22002201 :11..00 <1.0 <1.0 <1.0 7.7§.. <1.0 <1.0 <1.0 51.8 8l68
TW4-29 . 2nd Qtr 6/19/2013 <1.0 242 <1.0 <1.0 44.8 4.60 2nd Qtr 7/11/2013 <1.0 262 <1.0 <1.0 37.7 3.52 3rd Qtr 9/26/2013 <1.0, 246 „ <1.0 <1.0 41.4 4.18 4th Qtr 11/13/2013 <1.0 260 <1.0 <1.0 1st Qtr 2/5/2014 <1.0 258 <1.0 <1.0 14.4 4.63
2nd Qtr 5/22/2014 <1.0 262 <1.0 <1.0 38.2 3.52
3rd Qtr 8/27/2014 <1.0 242 <1.0 <1.0 41 3.40 41h Qtr 10/29/2014 <1.0 290 <1.0 <1S 41 3.64 1st Qtr 3/12/2015 <1.0 299 <1.0 <1.0 40.5 4.14 2nd Qtr 6/11/2015 <1.0 329 <1.0 <1.0 42.5 2.95
3rd Qtr 9/3/2015 <1.0 276 <1.0 <1.0 47.3 2.19
41h Qtr 10/29/2015 <1.0 631 <1 0 0 _.<1 39 8 2 74 1st Qtr 3/17/2016 <1.0 335 <1.0 <1.6- 40.5 2.92 2nd Qtr 6/8/2016 <1.0 366 <1.0 <1.0 42.9 2.51 3rd Qtr 8/3/2016 <1.0 401 <1.0 <1.0 40.6 2,44
4th Qtr 10/26/2016 <1.0 392 <1.0 <2100 44.2 ........ 2.40
1st Qtr 3/16/2017 <1.0 446 <1.0 .41.5 '2:2;4 2nd otr 6i4/2017 <1.6 420 <1.0 <1.0 42 2.26 3rd Qtr 8/4/2017 <1.0 466 <1.0 <1.0 42.9 2.35 41h Qtr 10/11/2017 <1.0 431 <1.0 <1.0 37.7 2.45
1st Qtr 3/14/2018 <1.0 533 <1.0 <1.0 43.1 2.44 2nd Qtr 6/14/2018 <1.0 474 <1.0 <1.0 40.1 2.67 3rd Clir 8/29/2018 <1.0 454 <1.0 <1.0 45.9 2.52

tr 12/13/2018

41 tsht QQtr 3/20/2019 <1.0 <1.0 521 507 <1.0 <1.0 <1.0 <1.0 40.9 39.9 2.50 2.6
2nd Qtr 6/13/2019 <1.0 537 <1.0 <1.0 39.4 2.56 3rd Qtr 9/12/2019 <1.0 549 <1.0 <1.0 38 2.55 4th Qtr 2/18i2019 1st Qtr 3/18/2020 <1.0 <1.0 630 652 <1.0 <1.0 <1.0 <1.0 44.8 ............. 41 .... 2.:§.8 2.16 2nd Qtr 6/12/2020 <1.0 686 <1.0 <1.0 42.2 3.18
3rd Qtr 9/19/2020 <1.0 621 <1.0 <1.0 39.9 2.90 41h Qtr 11/11/2020 <1.0 671 <1.0 <1.0 40.8 3.27 DWMRC ample <10 670 <20 <20 42 0.75 H tst Qtr 3/24/2021 <1.0 577 <1.0 <1.0 44.3 3.09 = Sam le was analvzed beyond holdrn< times and may not be accureate concentraton
TW4-30
2nd Qtr 6/19/2013 <1.0 <1.0 <1.0 <1.0 36 0.95
3rd Qtr 9/26/2013 <1.0 <1.0 <1.0 <1.0 36.3 0.952 4th Qtr 11/13/2013 <1.0 <1.0 <1.0 <1.0 35.9 1.24 1st Qtr 1/23/2014 <1.0 „ „ . <1.0 <1.0 <1.0 36.9 1.36
2nd Qtr 5/22/20 „ 14 <1.0 .1.0 <1.0, <1.0 31.9 1.44
3rd Qtr 8/23/2014 <1.0 <1.0 <1.0 <1.0 38 1.5

r 10/23/2014

41 tsht Q ttr 3/11/2015 Q <1.0 <1.0 <1.0 1.65 <1.0 <1.0 <1.0 <1.0 37.1 38.3 1.84 2.15 2nd Qtr 6/11/2015 <1.0 2.25 <1.0 <1.0 40.3 1.75 3rd Qtr 9/3/2015 <1.0 3.27 <1.0 <1.0 44.2 1.75
<1.0 3.48 <1.0 <1.0 37.8 1.86

41 tsht Q 10/28/2015 tt rr

Q 3/17/2016 <1.0 5.16 <1.0 <1.0 39.6 2.74 2nd Qtr 5/26/2016 <1.0 7.38 <1.0 <1.0 40.2 2.04 3rd Qtr 8/3/2016 , <1.0 6.79 <1.0 <1.0 38.6 2.32 401.gt..... . J9/40/2016 <1.6 8.69 <1.0 <1.0 41.3 2.51
'1st Qtr iiiiYo'fi ..1.:6*-- 13.6 <1.0 1.0 37.7 2.70 2nd Qtr 6/15/2017 <1.0 15.2 <1.0 <1.0 37.8 2.95 3rd Gtr, 8/3/2017 <1.0 15.7 <1.0 <1.0 39.8 3.11 10/10/2017 41 isht QQ tt tr 3/15/2018 <1.0 <1.0 13.4 16.4 <1.0 <1.0 1.0 1.0 34.9 41 2.58 3.63
2nd otr 6/13/2018 <1.0 16.9 <1.0 <1.0 37.4 3.93
3rd Qtr 8/30/2018 <1.0 19.8 <1.0 <1.0 44.1 3.79
4.,t ..Rt....... ...121.12„/2.9.1.8, '.1..,0 ,. ........ 23.9 <1.0 <1.0 35.5 3.70 ..1 st Qtr 3/15/2019 <1.0 25.3 <1.0 <1.0 35.9 4.08 2nd Qtr 6/13/2019 <1.0 31.5 <1.0 <1.0 27.2 4.13 3rd Qtr 9/11/2019 <1.0 34.8 <1.0 <1.0 34.5 3.79.
401 Qtr 12/18/2019 <1.0 44.9 <1.0 <1.0 39.1 3.62
1st Qtr 3/17/2020 <1.0 53.1 <1.0 <1.0 37.5 3.85
2nd Qtr 6/12/2020 <1.0 65.4 01.0, <1.0 38.6 3.69.
3rd Qtr 9/18/2020 <1.0 67.7 <1.0 <1.0 35 3.49 4th Qtr 11/11/2020 <1.0 82.8 <1.0 <1.0 37.1 3.64 DWMRC spq sEnple <10 66 <20 <20 39 P 1st Qtr - 3/17/2021 <1.0 74.8 <1.0 <1.0 37.6 ..AI.7,!
Shaded indicates concentrabons exceeding GWQS. H = Sample was analyzed beyond holding times and may not be accureate concentrabon.
TABLE 1 (29 of 31)
Historic Summary Of Monitoring Well Analytical Results Up To The lst Qarter 2021
Chloroform Contamination Investigation
DUSA White Mesa Mill
TW4-31
Sampling Event Parameter
(GWQS)
Carbon Tetrachloride
(5 pg/L)
Chloroform
(70 pg/L)
Chloromethane
(30 pg/L)
Methylene Chloride
(5 pg/L)
Chloride
No GWQS (mg/L)
Nitrate, Nitrate . Nitrite
(10 mg/L) 2nd Qtr 6/19/2013 <1.0 <1.0 <1.0 <1.0 28.4 1.3 3rd Qtr 9/5/2013 <1.0 <1.0 <1.0 <1.0 29.4 1.1 41h Qtr 11/7/2013 <1.0 <1.0 <1.0 <1.0 28 1.33 1st Qtr 1/23/2014 <1.0 <1.0 <1.0 <1.0 28.5 1.32 2nd Qtr 5/21/2014 <1.0 <1.0 <1.0 <1.0 26.3 1.22 3rd Qtr 8/13/2014 <1.0 <1.0 <1.0 <1.0 30 1.1 4th Qtr 10/28/2014 <1.0 <1.0 <1.0 <1.0 37.1 1.84 1st Qtr 3/11/2015 <1.0 <1.0 <1.0 <1.0 30.6 1.33 2nd Qtr 6/10/2015 <1.0 <1.0 <1.0 <1.0 31.1 1.19 3rd Qtr 9/2/2015 <1.0 <1.0 <1.0 <1.0 30.4 0.916 41h Qtr 10/21/2015 <1.0 <1.0 <1.0 <1.0 _ 29.1 0.953 _ 1st Qtr 3/11/2016 <1.0 <1.0 <1.0 <1.0 31.5 1.84 2nd Qtr 5/25/2016 <1.0 <1.0 <1.0 <1.0 32.5 1.36 3rd Qtr 7/28/2016 <1.0 <1.0 <1.0 <1.0 30.6 1.41 4th Qtr 10/20/2016 <1.0 <1.0 <1.0 <11 .0 <.0 34 1.14 1st Qtr 3/15/2017 <1.0 <1.0 <1.0 31.3 1.19 2nd Qtr 6/15/2017 <1.0 <1.0 <1.0 <1 0 33.4 1.21 3rd Qtr 8/2/2017 <1.0 <1.0 <1.0 <1.0 33 1.11 41h Qtr 10/10/2017 <1.0 <1.0 <1.0 <1.0 30.9 1.04 1st Qtr 3/14/2018 <1.0 <1.0 <1.0 <1.0 38.8 0.916 2nd Qtr 6/12/2018 <1.0 <1.0 <1.0 <1.0 34.4 0.948 3rd Qtr 8/29/2018 <1.0 <1.0 <1.0 <1.0 40.3 0.710 4t5 Qtr 12/12/2018 <1.0 <1.0 <1.0 <1.0 35.2 0.766 1st Qtr 3/16/2019 <1.0 <1.0 <1.0 <1.0 35 0.754 2nd Qtr 6/13/2019 <1.0 <1.0 <1.0 <1.0 36.9 0.713 3rd Qtr 9/11/2019 <1.0 <1.0 <1.0 <1.0 35.8 0.61 4th Qtr 12/14/2019 <1.0 <1.0 <1.0 <1.0 4,0,6. .........Q§.2. l st Qtr 3/17/2020 <1.0 <1.0 <1.0 <1.0 38.2 0.572 2nd Qtr 6/12/2020 <1.0 <1.0 <1.0 <1.0 36.7 0.569 3rd Qtr 9/17/2020 <1.0 <1.0 <1.0 <1.0 36.5 0.51 41h Qtr 11/4/2020 <1 0 <1.0 <1.0 <1.0 1st Qtr 3/17/2021 <1.0 <1.0 <1.0 <1.0 .Vil. .--g1g1 TW4-32
4th Qtr 11/14/2013 <1.0 <1.0 <1.0 <1.0 52.1 4:6. l st Qtr 1/22/2014 <1.0 <1.0 <1.0 <1.0 54.5 5.11 2nd Qtr 5/21/2014 <1.0 <1.0 <1.0 <1.0 54.9 5.63 3rd Qtr 8/13/2014 <1.0 <1.0 <1.0 <1.0 64 4.2 4th Qtr 10/23/2014 l st Chr 3/11/2015
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0 ..".!:.9 <1.0 §;§., 64.2 2..14. 2.46 Durecate TW4-65 <1.0 <1.0 <1.0 <1.0 65.9 2.25 2nd Qtr 6/10/2015 <1.0 <1.0 <1.0 <1.0 62.7 1.21 3rd Qtr 9/2/2015 <1.0 <1.0 <1.0 <1.0 5.09 10/21/2015 41 tsht tt <1.0 <1.0 <1.0 _ <1.0 _
559
.
.6
1 5 _ 1.19 QQ rr 3/15/2016 <1.0 <1.0 <1.0 Zili- 64.2 4.4: 2nd Qtr <1.0 <1.0 <1.0 <1.0 71.8 3.16 3rd Qtr 7/28/2016 <1.0 <1.0 <1.0 <1.0 64.4 3.44 4th Qtr 10/19/2016 <1.0 <1.0 <1.0 <1.0 66 2.87 1st Qtr 3/17/2017 <1.0 <1.0 <1.0 <1.0 62.8 2.82 2nd Qtr 6/15/2017 <1.0 <1.0 <1.0 <1.0 53.5 2.37 3rd Qtr 8/2/2017 <1.0 <1.0 <1.0 <1.0 65.8 2.47 4th Qtr 10/10/2017 <1.0 <1.0 <1.0 <1.0 65.8 2.47 1st Qtr 3/14/2018 <1.0 <1.0 <1.0 <1.0 65.4 2.94 2nd Qtr 6/12/2018 <1.0 <1.0 <1.0 <1.0 59.2 2.51 3rd Qtr 8/29/2018 <1.0 <1.0 <1.0 <1.0 68.1 2.56 4th Qtr 11/30/2018 <1.0 <1.0 <16 <1.0 57.5 2.50 1st Qtr 3/16/2019 <1.0 <1.0 <1.0 <1.0 5 7 .5 2.15 2nd Qtr 9/11/2019 <1.0 <1.0 <1.0 <1.0 60.1 2.18 3rd Qtr 9/11/2019 <1.0 <1.0 <1.0 <1.0 55 1.84 4th Qtr 12/14/2019 <1.0 <1.0 <1.0 <1.0 .89 1 st Qtr 3/17/2020 <1.0 <1.0 <1.0 <1.0 .......86:.; ---.111; 2nd Qtr 6/10/2020 <1.0 <1.0 <1.0 <1.0 57.0 2.19 3rd Qtr 9/17/2020 <1.0 <1.0 <1.0 <1.0 50.8 1.58 4t6 Qtr 11/4/2020 <1.0 <1.0 <1.0 <1.0 53.7 1.74 1st Qtr 3/17/2021 <1.0 <1.0 <1.0 <1.0 60.5 1.80 TW4-33 4th Qtr 11/14/2013 <1.0 126 <1.0 <1.0 47.2 1.82 1st Qtr 1/30/2014 <1.0 124 <1.0 <1.0 43.5 . 2.56 2nd Qtr 5/22/2014 <1.0 121 <1.0 <1.0 46.8 1.63 3rd Qtr 8/27/2014 <1.0 104 <1.0 <1.0 43 1.50 4th Qtr 10/29/2014 <1.0 124 <1.0 <1.0 44.2 2.22 1st Qtr 3/12/2015 <1.0 134 <1.0 <1.0 44.2 1.91 2nd Qtr 6/11/2015 <1.0 127 <1.0 <1.0 46.6 1.62 3rd Qtr 9/3/2015 <1.0 123 <1.0 <1.0 53.3 1.64 <1.0 129 ..... _. <1.0 .._ <1.0 44.5 _......_ 1.92 ._.

41 t
s
ht Q 10/29/2015 tt
r
r

Q

3/17/2016 <1.0 122 <1.0 <1.0 46.2 2.13 2nd Qtr 6/8/2016 <1.0 96.1 <1.0 <1.0 49.7 2.06 3rd Qtr 8/4/2016 <1.0 121 <1.0 <1.0 48.5 2.32 4 t
s
h Q
t (I tt
10/26/2016
r
r
3/17/2017
<1.0
<1.0 109 • 90.7 ..1 <1.0 <1.0 <10 <1.0 524
49.0 -11. 2nd Qtr 6/20/2017 <1.0 103 <1.0 <1.0 49.2 2.34 3rd Qtr 8/3/2017 <1.0 127 <1.0 <1.0 46.9 2.04 4th Qtr 10/11/2017 <1.0 97.1 <1.0 <1.0 42.5 1st Qtr 3/15/2018 <16 128 <16 <16 49.2 -711. 2nd Qtr 6/13/2018 <16 87.8 <1.0 <1.0 44.0 2.13 3rd Qtr 9/5/2018 <1.0 113 <1.0 <1.0 50.0 1.82 12/13/2018 41 tsht QQtrtr <1.0 141 <1.0 <1.0 43.2
3/20/2019 <1.0 86.2 <1.0 <1.0 .47: 1 3 .1 2nd Qtr 6/19/2019 <1.0 121 <1.0 <1.0 43.4 2.16 3rd Qtr 9/12/2019 <1.0 101 <1.0 <1.0 41.1 1.61 12/18/2019 41 t
s
ht QQ tt
r
r <1.0 117 . <10 <10 . 48.8 ........... 1.86 ........... 3/18/2020 <1.0 93.7 <1.0 <1.0 45.3 2.44 2nd Qtr 6/10/2020 <1.0 90.1 <1.0 <1.0 48.9 3.26 3rd Qtr 9/18/2020 <1.0 84.9 <1.0 <1.0 51.0 3.58 4t6 Qtr 11/11/2020 <1.0 80.6 <1.0 <1.0 51.5 3.71 pWMRG split sample <10 68 <20 <20 54 0.12 H - - - -.3718/2021 lst Cltr <1.0 64.9 <1.0 <1.0 55.6 4.62
Shaded indicates concentrations exceeding GW0S.
H = Sample was analyzed beyond holdrng times and may not be accureate concentration.
TABLE 1 (30 of 31)
Histonc Summary Of Monitonng Well Analytical Results Up To The 1st Qarter 2021 Chloroform Contamination Investigation
DUSA White Mesa Mill
TW4-34 Sampling Event Parameter (GWQS)
Carbon Tetrachloride (5 pg/L) Chloroform (70 pg/L) Chloromethane (30 pg/L) Methylene Chloride (5 pg/L) Chlonde No GWQS (mg1L) Nitrate, Nitrate -i- Nitnte (10 mg/L)
4th Qtr 11/14/2013 <1 0 <1 0 <1 0 <1 0 19 2 64 1st Qtr 1/23/2014 <1 0 <1 0 <1 0 <1 0 20 4 63 2nd Qtr 5/22/2014 <1 0 <1 0 <1 0 <1 0 17 9 69 3rd Qtr 8/13/2014 <1 0 <1 0 <1 0 <1 0 18 10
4th Qtr 10/29/2014 <1 0 <1 0 <1 0 <1 0 • 17 8 16 1st Qtr 3/11/2015 <1 0 <1 0 <1 0 <1 0 17 7 21 2nd Qtr 6/11/2015 <1 0 <1 0 <1 0 <1 0 17 4 0 868
3rd Qtr 9/3/2015 <1 0 <1 0 <1 0 <1 0 15 1 0 458
4th Qtr 10/21/2015 <1 0 <1 0 <1 0 <1 0 15 8 0 368 1st Qtr 3/16/2016 <1 0 <1 0 <1 0 <1 0 17 3 0 925 2nd Qtr 5/25/2016 <1 0 <1 0 <1 0 <1 0 18 0 605
3rd Qtr 8/3t2016 <1 0 <1 0 <1 0 <1 0 17 2 0 726
4th Otr 10/20/2016 <1 0 <1 0 <1 0 <1 0 19 • 0 612 1st Qtr 3/15/2017 <1 0 <1 0 <1 0 <1 0 18 0 0 674 2nd Qtr 6/15/2017 <1 0 <1 0 <1 0 <1 0 15 7 0 727 3rd Qtr 8/2/2017 <1 0 <1 0 <1 0 <1 0 19 8 0 733
4th Qtr 10/10/2017 <1 0 <1 0 <1 0 <1 0 18 5 0 774
Duphcate "RN4-65 <1 0 <1 0 <1 0 <1 0 20 4 0 784 1st Qtr 3/14/2018 <1 0 <1 0 <1 0 <1 0 19 1 0 737 2nd Qtr 6/13/2018 <1 0 <1 0 <1 0 <1 0 19 5 0 877 3rd Qtr 8/29/2018 <1 0 <1 0 <1 0 <1 0 23 8 0 736
4th Qtr 12/12/2018 .. <1 0 <1 0 <1 0 <1 0 18 5 0 889
1st Qtr 3'716/2019 <1 0 <1 0 <1 0 <1 0 17 9 0 859
2nd Qtr <1 0 <1 0 <1 0 <1 0 20 1 0 994 3rd Qtr 9/11/2019 <1 0 <1 0 <1 0 <1 0 17 8 0 934 4th Qtr 12/14/2019 <1 0 <1 0 <1 0 <1 0 21 4 1 07
1st Qtr 3/17/2020 <1 0 <1 0 <1 0 <1 0 20 1 1 090
2nd Qtr 6/10/2020 <1 0 <1 0 <1 0 <1 0 20 9 1 240 3rd Qtr 9/17/2020 <1 0 <1 0 <1 0 <1 0 19 0 0 978 4th Qtr 11/4/2020 .. <1 0 <1 0 <1 0 <1 0 18 7 1 04 1st Qtr 3/17/2021 <1 0 <1 0 <1 ci <1 0 19 3 1 09
TW4-35
3rd Qtr 8/27/2014 <1 0 <1 0 <1 0 <1 0 34 0 2
.. .. <1 0 . <1 0 . <1 0 <1 0 34 1 0 351 4tsht Qtr._ 10/28/2014 i Qtr <1 0 <1 0 <1 0 <1 0 34 9 0 436 2nd Qtr 6/10/2015 <1 0 <1 0 <1 0 <1 0 35 2 0 452 3rd Qtr 9/3/2015 <1 0 <1 0 <1 0 <1 0 35 9 0 304 4th Qtr 10/28/2015 <1 0 <1 0 <1 0 < 33 4 0 419
1st Qtr 3/16/2016 <1 0 <1 0 <1 0 00 <11 35 4 0 521
2nd Qtr 5/26/2016 <1 0 <1 0 <1 0 <1 0 35 4 0 631 3rd Qtr 8/3/2016 <1 0 <1 0 <1 0 <1 0 34 8 0 723 45h Qtr 10/20/2016 <1 0 <1 0 <1 0 <1 0 37 1 0 626 1st Qtr 3/15/2017 <1 0 <1 0 <1 0 <1 0 33 7 0 673
2nd Qtr 6/15/2017 <1 0 <1 0 <1 0 <1 0 34 8 0 699
3rd Qtr 8/2/2017 <1 0 <1 0 <1 0 <1 0 36 3 0 670 41h Qtr 10/10/2017 <1 0 <1 0 <1 0 <1 0 31 7 0 651 1st Qtr 3/14/2018 <1 0 <1 0 <1 0 <1 0 37 4 0 740 2nd Qtr 6/13/2018 <1 0 <1 0 <1 0 <1 0 33 7 0 662
3rd Qtr 8/30/2018 <1 0 <1 0 <1 0 <1 0 39 3 0 527
4th Qtr 12/12/2018 _ _ <1 0 <1 0 . <1 0 <1 0 43 0 0 559
1st Qtr 3/16/2019 <1 0 <1 0 <1 0 <1 0 33 5 0 574 2nd Qtr 6/13/2019 <1 0 <1 0 <1 0 <1 0 35 5 0 670 3rd Qtr 9/11/2019 <1 0 <1 0 <1 0 <1 0 31 7 0 525
4th Qtr 12/14/2019. <1 0 . <1 0 <1 0 <1 0 37 4 0 524
1st Qtr 3/17/2020 <1 0 <1 0 <1 0 <1 0 34 5 0 595 2nd Qtr 6/11/2020 <1 0 <1 0 <1 0 <1 0 34 0 0 699 3rd Qtr 9/17/2020 <1 0 <1 0 <1 0 <1 0 32 2 0 760 4th Qtr_ 11/4/2020 <1 0 <1 0 <1 0 <1 0 30 4 0 756,
1st Qir 3/17/2021 ,---_ <1 0 <1 0 <1 0 <1 0 35 6 0 991. 11171r-36 <1 o <1 0 <1 o <1 0 65 <0 1
4th Qtr 10/23/2014 <1 0 <1 0 <1 0 <1 0 67 3 <0 1.
1st Qtr 3/11/2015 <1 0 <1 0 <1 0 <1 0 67 2 <0 1
2nd Qtr 6/10/2015 <1 0 <1 0 <1 0 <1 0 69 3 <0 1 3rd Qtr 9/3/2015 <1 0 <1 0 <1 0 <1 0 76 4 <0 1 4th Qtr 10/21/2015 <1 0 <1 0 <1 0 <1 0 64 5 <0 1
1st Qtr 3/11/2016 <1 0 <1 0 <1 0 <1 0 67 2 <0 1'
2nd Qtr 5/26/2016 <1 0 <1 0 <1 0 <1 0 72 3 <0 1 3rd Qtr 7/28/2016 <1 0 <1 0 <1 0 <1 0 69 4 <0 1 4th Qtr 10/20/2016 <1 0 <1 0 <1 0 <1 0 73 8 <0 1 Duplicate TW4-70 lst Qtr 3/15/2017 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 <1 0 • 72 60 2 <<00 11.
2nd Qtr 6/15/2017 <1 0 <1 0 <1 0 <1 0 71 3 <0 1
3rd Qtr <1 0 <1 0 <1 0 <1 0 69 6 <0 1 4th Qtr 10/10/2017 <1 0 <1 0 <1 0 <1 0 62 9 0 104 1st Qtr 3/14/2018 <1 0 <1 0 <1 0 <1 0 73 8 <0 1 2nd Qtr 6/12/2018 <1 0 <1 0 <1 0 <1 0 64 3 <0 1
3rd Qtr 8/29/2018 <1 0 <1 0 <1 0 <1 0 76 4 <0 1
4th Qtr 12/12/2018 <1 0 <1 0 <1 0 <1 0 65 8 • 0 123
1st Qtr 3/16/2019 <1 0 <1 0 <1 0 <1 0 65 0 116. 2nd Qtr 6/13/2019 <1 0 <1 0 <1 0 <1 0 71 5 <0 1 3rd Qtr 9/11/2019 <1 0 <1 0 <1 0 <1 0 69 6 <0 1 4th Otr 12/14/2019 <1 0 <1 0 <1 0 <1 0 73 7 • <0 1 1st Qtr 3/17/2020 <1 0 <1 0 <1 0 <1 0 69 1 <0 1
2nd Qtr 6/11/2020 <1 0 <1 0 <1 0 <1 0 67 0 <0 1
3rd Qtr 9/17/2020 <1 0 <1 0 <1 0 <1 0 66 0 <0 1 4t5 Ott- 11/4/2020 • . <1 0 <1 0 <1 0 <1 0 64 0 <0 1 1st Qtr 3/17/2021 <1 0 <1 0 <1 0 <1 0 72 5 <0 1
Shaded indicates concentratons exceeding GWCIS
TABLE 1 (31 of 31)
Historic Summary Of Monitoring Well Analytical Results Up To The 1st Qarter 2021
Chloroform Contamination Investigation DUSA White Mesa Mill
TW4-37 (chloroforrn pumping well 6/9/15) Sampling Event
Parameter
(GWQS)
Carbon Tetrachloride
(5 pg/L)
Chloroform
(70 pg/L)
Chloromethane
(30 pg/L)
Methylene Chloride (5 pg/L) Chloride No GWQS (mg/L)
Nitrate, Nitrate -1- Nitrite
(10 mg/L)
2nd Qtr 6/8/2015 18.2 30,200 15.7 1.94 345 35.2
3rd Qtr 9/3/2915 16.6 19,100 13.7 1.04 374 32.4
12.5 19 500 9.38 1 .17 399 ......... ......... ..... 34.6

41 t
s
ht Q 10/19/2015 tt
r
r

Q
3/9/2016 15.8 17,500 3.57 1.34 332 28.4
2nd Qtr 5/23/2016 14.4 16,200 , 3.57 1.17 389 27.9
3rd Qtr 7/25/2016 16.7 15,900 <1.0 <1.0 294 33.4
10/12/2016 16.3 _18,400 <1.0 357 ,
<1.0 304 26.1 41 tsht QQ tt rr 3/8/2017 15.4 18 ,000 1.34 305 3/3
2nd Qtr 6/15/2017 16.2 15,800 <1.0 <1.0 281 31.2
3rd Qtr ' ' 7/26/2017 15.1 15,000 <1.0 <1.0 277 30.5
41h Qtr 10/11/2017 12 6 15,500 2.47 <1.0 -21 1st Qtr 3/12/2018 12.8 12,900 1.14 <1.0 300
2nd Qtr 6/8/2018 10.6 14,400 <1.0 <1.0 275 28.6
3rd Qtr 8/22/2018 12.1 14,100 6.2 <1.0 387 25.3
4th Qtr 11/28/2018 11.3 15,2gp 19.8 <1.0 264 .17....3 1st Qtr 3/8/2019 13.8 13,300 . 1.24 . . <1.0 209 - 30.1
2nd Qtr 6/5/2019 14.6 16,200 <1.0 <1.0 250 31.2
3r8 Qtr 9/4/2019 10.7 11,900 1.9 <1.0 , 228 25.8
4.:it.?..cgr.. 12/10/2019 8.81 13,100 3.12 <1.0 220 25.5
'ist Qtr 2/19/2020 .. 8.53 12,000 12.3 <1.0 236 28.3
2nd Qtr 5/27/2020 11.8 11,700 1.44 <1.00 , 321 28.3
3rd Qtr 9/4/2020 9.62 13,800 <1.0 <1.0 273 29.5
4th Qtr 10/28/2020 1st Qtr 2/23/2021 6.52 <1.0 10,39.0 8,380 29.4 <1.0
<1.0 <1.0 254 242 ---ir
TW4-38
4th Qtr 11/10/2016 <1.0 .0 <1.0 <1.0
1st Qtr 3/15/2017 <1.0 .0 <1.0 <1.0
2nd Qtr 6/15/2017 <1.0 <1..0 <1.0 <1.0 36.2 10.8
3rd Qtr 8/2/2017 <1.0 <1.0 <1.0 <1.0 36.9 10.1
4th Qtr 10/10/2017 <1.0 <1.0 <1.0 <1.0 31.3 10.3
1st Pt, 3/14/2018 <1.0 <1.0 <1.0 <1.0 . 36.5 9.34
2nd Qtr 6/13/2018 <1.0 <1.0 <1.0 <1.0 33.1 9.48
3rd Qtr 8/30/2018 <1.0 <1.0 <1.0 <1.0 39.2 7.77
4th Qtr 12/12/2018 <1.0 <1.0 <1.0 35.0 8.48
1st Qtr 3/16/2019 <1.0 .0 <1.0 01.0 33,5 8.96
2nd Qtr 6/13/2019 <1.0 <1.0 <1.0 <1.0 33.7 8.53
Duplicate TW4-70 <1.0 <1.0 <1.0 <1.0 35.3 9.52
3rd Qtr 9/11/2019 <1.0 <1,0 <1,0 <1.0 31.6 7.61
4th Qtr 12/14/2019 <1.0 <1.0 <1.0 <1.0 36 7.51
1st Qtr 3/17/2020 <1.0 <1.0 <1.0 <1.0 33.4 8.11 „. „
2pd Qtr 6/11/2020 <1.0 <1.0 <1.0 <1.0 34.9 9.00
3rd Qtr 9/18/2020 , <1.0 <1.0 <1.0 <1.0 34.7 7.35
4th Qtr 11/4/2020 <1.0 1.0 <1.0 <1.0 35.1 7.72
1st Qtr 3/18/2021 <1.0 < <1.0 <1.0 37.2 8.24
TIN4-39tomororo.r.,..0,,.. (1.016) 41h Qtr 11/11/2016 <1.0 2,800 <1.0 <1.0 68.9 20.7
1st Qtr 3/8/2017 8.15 6,460 <1.0 1.35 130 6.44
2pd Qtr 6/15/2017 8.2 5,560 <1.0 1.31 120 6.25
3rd qtr._ 7/26/2017 14.4 10,000 <1.0 1.5 132 7.74
41h Qtr 10/10/2017 <1.0 552 <1.0 <1.0 73.5 2.65
1st Qtr 3/12/2018 3.1 2,870 <1.0 <1.0 ,11,3 3.33
2pd Qtr 6/8/2018 7.94 7,160 <1.0 <1.0 107 4.84
3rd Qtr 8/22/2018 12.5 8,180 2.33 <1.0 110 6.05
4th Qtr 11/28/2013 1st Qtr 3/8/2019
6. 10 .2 8 ..§..,?0 885 2.33 <1.0 <1.0 <1.0
123
49
6.39 2.08
2nd Qtr 6/5/2019 11.6 8,640 <1.0 <1.0 114 8.45
3I'd.. Plr 9/4/2019 5.71 4,240 <1.0 <1.0 48.2 1.75
41n Qtr 12/10/2019
lst Qtr 2/19/2020
1.14 <1.0 . 1850 812 <1.0 <1.0 :11..00 74.7 76.5 665 0.792
2nd citr 5/27/2020 7.56 5,870 <1.0 <1.0 88.5 5.010
3rd Qtr 9/18/2020 8.18 , 5,960 <1.0 <1.0 '63-. , 2.69
4th Qtr 10/28/2020 <1.0 648 1.19 <1.0 83.2 7.03
1st Qtr V23/2021 <1.0 2 970 <1.0 <1.0 53.0 2.12
TIN4-40(chloroform pumping well .019)
1st Qtr .. <1.0 248 <1.0 <1.0 35.7 Toi
2nd Qtr 6/13/2018 <1.0 131 <1.0 <1.0 31.6 3.33
3rd qpr, 9/5/2018 <1.0 113 <1.0 <1.0 37.6 3.22
41h Qtr 12/12/2018 <1.0 118 <1.0 <1.0 29.9 3.54
(ITypripate TW4- <1.0 119 <1.0 <1.0 32.3 'n (2LI st Qtr 3/20/2019 <1.0 111 <1.0 <1.0 30.9
2nd Qtr 6/5/2019 <1.0 263 <1.0 41.0 35.6 3.55.
3rd Qtr 9/4/2019 <1.0 , 380 <1.0 01.0 35.9 3.39
4th Qtr 12/10/2019 <1.0 314 <1.0 <1.0 36.7 .?.:§.? 1st Qtr 2/19/2020 <1.0 364 <1.0 <1.0 38.5 2.96
2nd Qtr 5/27/2020 <1.0 367 <1.0 <1.0 36.5 2.91
3rd Qtr 9/4/2020 <1.0 333 <1.0 <1.0 34.2 2.88
4th Otr 10/28/2020 01.0 264 <1.0 <1.0 34.6 2.58
1st Qtr 2/23/2021 <1.0 436 3.51 <1.0 36.0 2:43.
TW4-41(obrotorn, purnping Aell 5/10111) 2nd Qtr 5/8/2018 <1.0 1,400 <1.0 <1.0 42.8 6.54
3rd Qtr 8/22/2018 <1.0 1,390 <1.0 <1.0 45.5 6.13
11/28/2018 <1.0 1,320 <1.0 <1.0 41.4 6.02 41 tsht 0Q tt rr 3/8/2019 <1.0 1,220 <1.0 <1.0 39.1 6.71
2nd Qtr 6/5/2019 <1.0 1,320 <1.0 <1.0 38.1 6.00
3rd Qtr 9/4/2019 <1.0 1,190 <1.0 <1.0 39.4 6 22
1 t
s
ht QQ tt
r
r 122/11109//220 02 190 0 ,1 <1 :0 1410 , 1,200
46.11 <1.0 <1.0
<1.0
<1.0
42.1 44.4 ----14
2nd Qtr 5/27/2020 <1.0 1,220 <1.0 , <1.0 41.7 6.78
3rd Qtr 9/4/2020 <1,0 1,110 <1.6 <1.6 40.2 6.69
10/28/2020 <1.0 1,020 <1.0 <1.0 39.7 6.25 rr 41 tsht QQ lt 2/23/2021 <1.0 1,170 <1.0 <1.0 40.6 6.41
TW4-42 2nd Qtr 6/19/2019 <1.0 <1.0 <1.0 <1.0 23.3 2.57
3rd Qtr 9/11/2019 <1.0 <1.0 <(.0 <1.0 20.6 2.75
41h Qtr 12/10/2019 <1.0 <1.0 <1.0 <1.0 22.6 2.82
2.iplisata1W4-75 <1.0 ...._ ..... _ <1.0 <1.0 <1,0_ _22.6 2 95
1st Qtr 2/17/2020 <1.6 <1.0 <170 <7.0 23.2 2.88
2nd Qtr 6/10/2020 <1,0 <1.0 <1.0 <1.0 23.2 2.88
3rd Qtr 9/17/2020 <1.0 <1.0 <1.0 <1.0 23.5 3.65
41h Qtr 31/11/74f/2200220i 1st Qtr
:11..00 <1.0 <1.0 <1.0 <1.0
<1.0
<1.0
22.4 24.2 1.7i75
Shaded indicates concentrations exceeding GWQS. (1) VOCs were resampled because laboratory missed holding time. (2LCh0roform pumirj Weil stated in Mbr 2019.
Table 2
Summary of EFR QA/QC Samples
1st Quarter 2021
Duplicate Samples of Wells
Parameter GWQS Duplicate of TW4-3 Duplicate of TW4-9 Duplicate of MW-32
TW4-3 TW4-65 RPD TW4-9 TW4-70 RPD MW-32 TW4-75 RPD
Chloride none 28.4 27.6 2.9 40.7 38.7 5.0 36.8 37.4 -1.6 Nitrate + Nitrite (as N) 10 ma 6.19 6.64 -7.0 1.06 1.07 -0.9 <1.0 <1.0 nc Chloroform 70 pg/L <1.0 <1.0 nc 39 38.2 2.1 <1.0 <1.0 nc Carbon tetrachloride 5 pg/L <1.0 <1.0 nc <1.0 <1.0 nc <1.0 <1.0 nc
Chloromethane 30 pg/L <1.0 <1.0 nc <1.0 <1.0 nc <1.0 <1.0 nc
Methylene Chloride 5 usa/L <1.0 <1.0 nc <1.0 <1.0 nc <1.0 <1.0 n
nc = not calculated
Tabel 3
Chloroform Mass Removal Calculations for the 1st Qurater 2021
EFR White Mesa Mill, Bland, Utah
Well ID MW4 MW-26 TW4-1 TW4-2 TW4-4 TW4-11 TW4-19 TW4-21 TW4-22 TW4-24 TW4-25 TW4-37 TW4-39 TW4-40 TW4-41
WChloroform (ug/L) 1,150 3,060 948 939 1,130 2,750 6,660 400 5,100 96.2 0.0 9,380 2,970 436 1,170 Chloroform (g/L) 1.15E-03 3.06E-03 9.48E-04 9.39E-04 1.13E-03 2.75E-03 6.66E-03 4.00E-04 5.10E-03 9.62E-05 0.00E+00 9.38E-03 2.97E-03 4.36E-04 1.17E-03 Chloroform (lbs/L) 2.54E-06 6.76E-06 2.09E-06 2.07E-06 2.50E-06 6.08E-06 1.47E-05 8.84E-07 1.13E-05 2.13E-07 0.00E+00 2.07E-05 6.56E-06 9.63E-07 2.59E-06 Chloroform (lbs/gal) 9.62E-06 2.56E05 7.93E06 7.85E-06 9.45E06 2.30E05 5.57E05 3.35E06 4.27E05 8.05E07 0.00E+00 7.84E05 2.48E-05 3.65E-06 9.78E06 Total gallons pumped 93486.7 27898.0 9066.4 13189.6 13740.8 2195.1 133462.3 97211.5 22605.6 81891.2 80272.2 59907.4 38932.4 72543.4 13407.5 lbs of chloroform removed 0.9 0.7 0.07 0.10 0.1 0.05 7.4 0.3 1.0 0.066 0.00 4.7 1.0 0.26 0.1 Gallons of chloroform removed 0.07 0.06 0.01 0.01 0.01 0.00_ 0.60 0.03 0.08 0.005 0.00 0.38 0.08 0.02 0.01
total lbs of chloroform removed 16.8
total gallons of chloroform removed 1.4
1) Assuming that the chloroform concentration result for the quarter monitoring event is the average chloroform concentration for the entire quarter.
Chloroform Pumping Wells
Nitrate Pumping Wells AB = Abandonded Well