DRC-2024-005023

State of Utah
SPENCER J. COX
Governor
DEIDRE HENDERSON
Lieutenant Governor
TO: Phil Goble
Department of
Environmental Quality
Kimberly D. Shelley
Erecutive Director
DIVISION OF WASTE MANAGEMENT
AND RADIATION CONTROL
Douglas J. Hansen
Director
MEMORANDUM
�6 �>/4<..l(
FROM: Dean Henderson
DATE: January 23, 2024
'
SUBJECT: Review of the November 15, 2023 3rd Quarter, 2023 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
November 15, 2023, 3rd Quarter, 2023 Chlorofom1 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.C requires the 3rd Quarter Report to be submitted to the Division on or before December
1, of each year. The Report was received by the Division on November 17, 2023 ( date of Report
November 15, 2023) which meets the GCAP requirement.
Monitor and Pumping Well Sampling
The following 43 monitor wells were sampled as required in the GCAP (see Table 1 below):
15 pumping wells: MW-4, MW-26, TW4-l, TW4-2, TW4-4, TW4-1 l, TW4-l 9, TW4-21, TW4-22,
TW4-24, TW4-25, TW4-37, TW4-39, TW4-40, and TW4-41.
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 I 00% recycled paper
DRC-2024-005023
Page 2
Current 5 performance monitoring ("PM") wells: TW4-7, TW4-10, TW4-16, TW4-26, and TW4-29.
Current 23 compliance monitoring ("CM") wells MW-32, TW4-3, TW4-5, TW4-6, TW4-8, TW4-9,
TW4-12, TW4-13, TW4-14, TW4-18, TW4-23, TW4-27, TW4-28, TW4-30, TW4-31, TW4-32, TW4-
33, TW4-34, TW4-35, TW4-36, TW4-38, TW4-42, and TW4-43.
The water samples for the above wells were analyzed for the following constituents as required in the
QAP:
Chloroform
Chloromethane
Carbon tetrachloride
Chloride
Methylene chloride
Nitrate + Nitrite as Nitrogen.
The analytical methods used is consistent with the requirements of the GCAP. For a summary of the 3rd
Quarter, 2023 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, TW4-42, TW4-43.
3.The pumping wells are continuously pumped on a set schedule and are sufficiently purged to
collect a sample
Page 4
•Excel spreadsheet that included: well name; well location (easting and northing); Laboratory
reported concentration in µg/1 in the 3rd Quarter, 2023 and corresponding log equivalent values.
•Surfer® griding parameters: kriging parameters: SURFER™default parameters (point kriging,
linear variogram, slope = 1, no anisotropy [anisotropy = 1], no search constraints; min x, max x
(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 111.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
lsoconcentration lines showing the 70 µg/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
Page 5
e)Electronic copy of all laboratory results for Chloroform Investigation monitoring conducted
during the quarter.
t)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 3rd Quarter, 2023 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).
Performance Monitor Wells ("PM") [Wells Exceeding Chloroform Concentrations GWOS of70µg/L]
Five (5) PM wells still exceed 70 µg/L: TW4-7, TW4-10, TW4-16, TW4-26, and TW4-29.
Compliance Monitor Wells ("CM") [Wells with Chloroform Concentrations between < 1 and 70µg/L]
Nine (9) CM wells range with detectable chloroform concentration but still below 70µg/L: TW4-5,
TW4-6, TW4-8, TW4-9, TW4-18, TW4-27, TW4-30, TW4-33, and TW4-35.
CM Wells Below the Laboratory Chloroform Detection Limit (<1.0 µg/L)
Fourteen (14) CM wells were below the laboratory detection limit for chloroform (<1.0 µg/L): MW-32,
TW4-3, TW4-12, TW4-13, TW4-14, TW4-23, TW4-28, TW4-31, TW4-32, TW4-34, TW4-36, TW4-
38, TW4-42, and TW4-43.
Pumping Wells
There are 15 pumping wells in full operation in the 3rd Quarter, 2023, 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 of70 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 (58.8 mg/L) and TW4-24 (26.2 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, approved on December 12, 2012.
Well TW4-26 (10.2 mg/1) continue to exceed the nitrate GWQS of 10 mg/1. The source of nitrate may
be from the chloroform source plume. Pumping well TW4-40 is located approximately 200 feet down a
gradient of TW 4-26 and the nitrate concentrations in the 3rd quarter 2023 were below the nitrate GWQS
of 1.88 mg/L. Therefore, at this time no action is recommended. However, should future nitrate
concentrations in down gradient pumping well wells increases to above 10 mg/L or shows an increasing
trend an additional investigation may be recommended
Well, TW4-27 (15.8 mg/L) continue to exceed the nitrate GWQS of 10 mg/1. 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 3rd quarter 2023
MW-4 {chlofolorm pump,ng we11 .wtedpump,ngl/4.QJ) Sampling Event
TABLE 1 (1 of 33)
Historic Summary Of Monitoring Well Analytical Results Up To The 3rd Quarter 2023 Chloroform Contamination Investigation
DUSA White Mesa Mill
Parameter
IGWQSI
Carbon Tetrachloride Chloroform Chloromethane Methylene Chloride Chloride Nitrate, Nitrate+ Nitrite (5 ug/L) (70 ug/Ll 130 uo/Ll (5 µn/Ll No GWQS (mn/L) (10mg/L)
1stQtr 3/16/2005 12nd Qtr 5125/2005
l3rd0tr 8/31/2005 th Qtr 12/7/2005
stQtr 3/9/2006
12nd Qtr 6/14/2006 3rdQtr 712012006
th Qtr 11/8/2006 stOtr 2128/2007
2nd Qtr 6127/2007
3rd Ctr 8/15/2007 th Qtr 10/10/2007 stQtr 3/28/2008 2nd Qtr 6/25/2008 3rdQtr 9/10/2008 th Qtr 10/15/2008 stQtr 3/4/2009 2nd Qtr 6/23/2009 3rdQtr 9/14/2009
th Qtr 12/14/2009 St"Cltr 2/17/2010 2nd Qtr 6/14/2010 Qtr 8/6/2010 Qtr 10/15/2010 Qtr 2123/2011 dQtr 6/1/2011 Qtr 8/17/2011 g/hr, 11/16/2011 1/23/2012 ind Qtr ----6/6/2012
3rdQtr 9/4/2012 4th Ctr 10/4/2012 1si"Otr 2/11/2013 2nd Qtr 6/5/2013 3rd Ctr 9/3/2013 4th Ctr 10/29/2013 1st0tr 1127/2014
2ndQtr 5/19/2014 3rd Ctr 8/11/2014 4th Qtr 10/21/2014 1st Qtr (2) 3/9/2015 2nd Qtr 6/8/2015 3rd Qtr 8/31/2015 4th Ctr 10/19/2015 1st0tr 3/9/2016
2nd0tr 5/23/2016 3rd Cir 7/25/2016 4th Qtr 10/1212016 1st Ctr 3/8/2017 2ndQtr 6/13/2017 3rd Ctr 7126/2017 4thQtr 10/11/2017
DWM�C splJ �.i:nple
1st Ctr 3/1212018 2nd Qtr 6/8/2018 3rd Ctr 8/2212018 4th Ctr 11/28/2018
1St"Otr 3/8/2019 2nd Qtr 6/5/2019
3rd Ctr 9/4/2019 4th Qtr 12/10/2019
1st Ctr 2/19/2020 2nd Qtr 5/2712020 3rd Otr 9/4/2020
4th Qtr 10/18/2020 1st0tr 2/23/2021
2nd0tr 6/9/2021 3rd Qtr 8/24/2021
4th0tr 12/1/2021 1stQtr 3/912022
2nd Otr 6/8/2022 3rd Qtr 8/30/2022 4thQtr 11/30/2022
1st0tr 3(7/2023
2nd Otr 6/6/2023 3rd Otr 8/9/2023
MW-4Al1W4-Al
1st Ctr 3/16/2005 2nd Qtr 5/25/2005
3rd Qtr 8/31/2005
4th Ctr 12/7/2005
1st0tr 3/9/2006
2nd Qtr 6/14/2006
3rd Qtr 712012006
4th Ctr 11/8/2006
1st Ctr 2128/2007
NA 2,900
NA 3,170
<10 3,500
<50 3,000
<50 3,100
<50 3,000
<50 2,820 2.1 2,830 1.6 2,300
1.8 2,000 1.9 2,600 1.7 2,300 1.7 2.400 1.8 2,500 1.8 1,800 1.7 2,100 1,5 2.200 1.3 1,800 1.4 2,000 1.6 1,800 1.2 1,600 1.2 2,100 1.5 1,900 1.4 1,500 1.5 1,700 1.4 1.700 1.1 1,700
q_ 1,600 1 1,500 1.2 ---,:.oo 1.5 1,500 1 1,300 1.48 1,670 1.31 1,490 1.13 1,520 5.58 1.410 4.15 1,390 5.21 1,390 76 1,490
<1.0 1.440 1.26 ---,:.oo
<1.0 1.300
<1.0 1.200
<1.0 1.200
<1.0 1,240 1.44 1,580 <1.0 1,430 1.24 1,470 1.22 1,450 1.15 1,430 1.15 1,400
<1.0 1,320 <19 1.400 1.07 1,320
<1.0 1,240 <1.0 1.300
<1.0 1,330 <1.0 1,190
<1.0 1.300
<1.0 1.180
<1.0 1,370
<1.0 1,230
<1.0 1,250 <1.0 1,240 <1.0 1,050
<1.0 1,150 <1.0 1,320
<1.0 1,140 <1.0 1.100
<1.o 1,040
<1.0 1,010
<1.0 1,200
<1.0 1,170
<1.0 1,010 <1.0 1,050 <1.0 1 030
NA 3,700 NA 3.740
<10 3,800
<50 3.000
<50 3.700
<50 3,300
<50 3,190
2.4 3,370 1.9 2,500
(1) As of March 2012 both north and south WIid life ponds no longer reeeMf'l!J water
{2)chlofoform pumpll'lg_wells TW4-1 TW4-2. and TW4-11 &laf1ed in 1114115 __ _
NA "' not analyzed
Shaded indicate& concentrations exceeding GWQS
Bold and italics indicates the MDL exceeded the GWOS
J "Approximated value
NA NA
NA NA <10 <10
<50 <50
<50 <50
<50 <50
<50 <50
1.4 <1.0 <1.0 <1.0
<1.0 <1.0
<1.0 <1.0 <1.0 <1.0
<1.0 <1.0 <1.0 <1.0 <1.0 <1.0
<1.0 <1.0 <1.0 <1.0 <1.0 <1.0
<1.0 <1.0 <1.0 <1.0
<1.0 <1.0 <1.0 <1.0
<1.0 <1.0
<1.0 <1.0 <"'fb <1.0
<1.0 <1.0 <1.0 <1.0
<1.0 <1.0 <1.0 <1.0 <TO ______ <1.0 ---
<1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 -<f"b <1.0 <1.0
<1.0 <1.0 <1.0 <1.0
<1.0------<1.0 ----
<1.0 <1.0 1.42 <1.0 <1.0 <1.0
<1.0 <1.0 <1.0 <1.0 <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 70 J
:.;;··ro <1.0
<1.0 <1.0 <1.0 <1.0
<1.0 <1.0 <1.0 <1.0
<1.0 <1.0 <1.0 <1.0
<1.0 <1.0 <1·.·o <1.0
<1.0 <1.0
<1.0 <1,0 <1.0 <1.0
<1.0 <1.0 <1.0 <1.0
<1.0 <1.0 <1.0 <1.0
<1.0 <1.0
<1.0 <1.0 <1.0 <1.0 <1.0 <1.0
<1.0 <1.0
2.0 <1.0 <1.0 <1.0
NA NA NA NA <10 <10
<50 <50
<50 <50
<50 <50
<50 <50
<1.0 <1.0
<1.0 <1.0 Well abandonded
NA
NA NA
NA
NA
NA
6.3 7.1 7.0 53 7.0 49 6.0 49 6.0 48 1.2 50 6.4 47 6.3 45 7.0 47 6.2 45 6.2 42 5.8 42 6.1 35 6.4 45 5.9 37 5.7 34 5.2 43 5.3 44 5.8 45 4.0 41 5.1 38 4.8 41 4.9 40 4.6 35 4.9 41 4.9 40 5.1 ffo • 4.8 39.0 4.9 41.0 5.0 41.0 4.8 37.8 4,78 44.0 4.22
41.4 4.89 40.1 5.25 38.5 -··u
39.9 4.08 41.0 3.7 41.5 5.07 40.7 5.75 43.1 2.53 44.3 4.79 40.8 4.43 42.2 5.15 43.7 4.54 42.5 4.95 44.8 4.88 43.3 4.99 44.0 4.88 43.8 4.59 43.8 5.25 43.0 5.1 46.2 4.47 43.5 4.64 48.5 4.55 43.1 4.44 41.5 5.05 40.6 5.16 41.9 4.69 45.5 4.34 48.1 6.22 40.7 5.04
43.8 4.93 41.4 4.62 46.5 4.61 34.8 6.48 43.2 3.83 47.6 4.90 40.9 4.80 43.7 3.90 44.7 4.20 35.9 4.05 29.4 4.44 37.0 4.20 44.7 3.90
7.1 7.8 6.9 55 6.7 53 5.8
54 7.3 54 1.2 54 7.1 60 7.1
TABLE 1 (2 of 33)
Historic Summary Of Monitoring Well Analytical Results Up To The 3rd Quarter 2023
Chloroform Contamination Investigation
DUSA White Mesa Mill
MW-26 (lormerTW4•15)Chlofolorm
purr,p,r,gwellstartec618J03 Parameter
Sampling Event IGWCSI
Carbon Tetrachloride Chloroform Chloromethane Methylene Chloride
3rdQtr 9/212002 4th Qtr 11/212002 1st0tr 3/3/2003 2nd Qtr 6/23/2003 3rd0tr 9/1212003 4th Qtr 11/8/2003
1st Ctr 3/16/2005 2nd Qtr 5/25/2005 3rd Ctr 8/31/2005 4th Qtr 1217/2005
1st Ctr 3/9/2006
2nd Qtr 6/14/2006
3rd0tr 7/20/2006 4th Qtr 11/8/2006 1st Ctr 2128/2007 2nd Qtr 6/2712007 3rd Ctr 8/15/2007 4th0tr 10/10/2007 1stQtr 3/28/2008 2nd Otr 6/25/2008 3rd Otr 9/10/2008 4th Otr 10/15/2008
11/18/2008 1st0tr 3/4/2009 2nd Qtr 6/23/2009 3rd Qtr 9/14/2009
4thCt1 12114/2009 1st0tr 2117/2010 2nd Qtr 6/14/2010 3rd Qtr 8/16/2010 4th Qtr 10/15/2010 1st0tr 2123/2011 2ndQtr 5/31/2011 3rd Otr 8/1712011 4th Otr 11/16/2011
11) 1215/2011 1ifQ'fr(If 212712012
2nd Ctr ----6/6/2012
<5.0
<50
<50
<50
<50
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0 <1.0 <1.0
<2.0 <1.0 <1.0 <1.0 <1.0 <1.0
<1.0 <1.0 <1.0 <1.0 <1.0
<1.0 <1.0
<1.0 3rd Qtr 9/4/2012 <1
4th Ctr 10/4/2012 <1 1stQtr 2/1H2013 <1 2ndQtr 6/5/2013 <1.0 3rd Otr 9/3/2013 <1.0 4thQtr 10/29/2013 <1.0 1st0tr 1/2712014 <1.0 2ndQtr 5/19/2014 <1.0 3rd Otr 8/11/2014 <1.0 4thQtr 10/21/2014 <1.0 1st0tr 3/9/2015 <1.0 2nd Ct, (3) 6/8/2015 <1.0
15 ua/L)
NA
NA ---NA
NA
NA
NA
NA
NA
NA
1.2
NA
3rd Otr ____ 8/31/2015 <1.0 _________
4th0tr 10/19/2015 <1.0 1stQtr 3/9/2016 <1.0 2ndQtr 5/23/2016 ill ----3rd Qtr 7125/2016 <1.0
110 uo/LI 130 uo/LI 15 uo/LI
2.6 NA NA <1.0 NA NA <1.0 NA NA
7800 NA NA
2500 NA NA
3000 NA NA
,_ 310 NA NA
442 NA NA
960 5.4 <5.0 1,000 <50 <50
1,100 <50 <50
830 <50 <50
2.170 <50 <50
282 <1.0 2.6
570 <1.0 5.5
300 <1.0 13
1.400 <1.0 36
2.000 <1.0 14
930 <1.0 40
1.300 <1.0 53
630 <1.0 ,-24
NA NA ,_ NA
1.700 <2.0 100
950 <1.0 51
410 <1.0 12
850 <1.0 30
1,100 <1.0 40
730 <1.0 19 1,600 <1.0 <1.0
2.200 <1.0 21
970 <1.0 6.5
450 <1.0 3.6
1.800 <1.0 ,_ 1.3
720 <1.0 72
NA NA NA
1.800 <1.0 2.9
2,400 <1.0 16 ----3:0ifo <TO ______ ----21 3,100 <1 31 1.200 <1 4 2.120 <1 9.34
4.030 <1.0 52.4
2,940 <1.0 33.2 1.410 <1 4.03
1.400 <1.0 13 8
1.960 <1.0 15.4
2.120 8.7 26
2.090 <1.0 23 2 1.980 <1.0 27 4
1,980 <1.0 11.2 ----i1so ------·res 11.6
2.680 1.32 8.28
2.650 <1.0 4.66
2.220 � 4.57
3.190 <1.0 7.81
4th Ctr (4) 10/1212016
1st Ot,-----3/8/2017
<1.0
<1.0 ----2,510 <1.0 ---------4)� ---·rnro <1.0------
2nd Ctr 6/13/2017 <1.0 2.450 3rd Qtr 7126/2017 <1.0 1.230 4thQtr 10/11/2017 <1.0 2.570
1s!Qtr 3/1212018 <1.0 1,210
2nd Ctr 6/8/2018 <1.0 1.870 3rd Otr 8/2212018 <1.0 1,680
4th Ctr 11/28/2018 <1.0 1.480 1stQtr 3/8/2019 <1.0 1.110
2ndQtr 6/5/2019 <1.0 1.280
3rd Qtr 9/4/2019 <1.0 1.680
4th Ctr 12110/2019 <1.0 1.390
1s!Qtr 2119/2020 <1.0 1.100 2nd Ctr 6/1212020 <1.0 1.140 3rd Qtr 9/4/2020 <1.0 1.130
4th Ctr 10/28/2020 <1.0 866
1s!Otr 2123/2021 <1.0 3.060 2ndQtr 6/6/2021 <1.0 998
3rd Qtr 8/24/2021 <1.0 1.580 4th Ctr 1211/2021 <1.0 826
1s!Qtr 3/9/2022 <1.0 1.030
2nd Otr 6/8/2022 <1.0 611 3rd Otr 8/30/2022 <1.0 612
4th Ctr 11/30/2022 <1.0 1.040
1s!Otr 3/9/2023 <1.0 571
2nd Qtr 6/13/2023 <1.0 2.230
3rdQlr 8/9/2023 <1.0 2 610 (1) voes were resampled because laboratory missed holding time.
���O�or:���!��=�w:�r���eceiWliWdter :
(4)chlorofDm'lpumprng�TW4-1 TW4•2 andTW4-11 &tarted in 1114115 __ _ NA = not analvzed Shaded indicates concentrations exceedinQ GWQS. Botd and italics 1ndtcates the MDL exceeded the GWQS
7.65
<1.0 7.59 <1.0 5 26 <1.0 7.83 <1.0 2.14 <1.0 9 19 <1.0 <1.0 <1.0 <1.0 <1.0 2.2 <1.0 1.19 <1.0 1.93 <1.0 1.78 <1.0 <1.0 <1.0 <1.0 <1.0 2.57 <1.0 <1.0 <1.0 3.46 <1.0 <1.0 <1.0 <1.0 5.9 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0
<1.0 <1.0 <1.0 <1.0 2.7 <1.0 <1.0 <1.0
Chloride
No GWCS Ima/LI
NA
NA
NA
NA
NA
NA
NA
NA
NA
55
52
52
65
54
56
49
57
57
49
57
44
64 NA 49 48
46
60
57
40
49
65
57 88 58
69
NA
98
---------73
73 68
81.9
77.9
60.5
72.3
59.4 53.4 59
60.1
56.5
62
69.6
62.6
68.3 66.2
---86.4 66.2
58.4
64.3
61.4
62.2
60.3
58.7
91.4 85.5 69.9
80.7
76.2
83.2 88.9
35.1
70
37.4
5f5 48.6 46.6
84.7
50.2
63.4
57.0
52.1
61
57.6
62.3
Nitrate, Nitrate+ Nitrite
I10m9/L)
NA
NA
NA ·-·-·"
NA
NA
NA
0.3
0.2
0.2
0.3
0.2
0.2
1.4
0.3
0.6
0.4
1
0.6
0.1
0.6
0.2
0.1 NA
0.4
0.2
0.1
2.3
0.2 6.8
0.6
0.7
0.5
0.4
0.9
2.0
NA 1.7
2.5
2.6 1.8
2.27
2.11
1.18
1.38
0.55
0.93
0.7
0.93
0.73
0.42
0.68
0.991
1.45
1.12
1.57 ---1.18
-------0.768
0.922
1.56
1.18
1.57
0.901
2.80
1.96
1.85
2.83
3.08
0.977
1.17
2.93
0.42
3.62 O.:i49
0.81
0.671
0.52
0.3
0.22
0.662
0.337
0.694
0.294
0.324
MW--32 (formerTW4-17) Sampling Event
TABLE 1 (3 of 33) Historic Summary Of Monitoring Wall Analytical Results Up To The 3rd Quarter 2023 Chlorofonn Contamination Investigation OUSA White Mesa Mill
Parameter IGWQSI Carbon Tetrachloride (5 pg/L) Chlorofonn Chloromethane Methylene Chloride Chloride (70 pg/L) (30 pg/L) (5 pg/L) No GWQS (mg/L) Nitrate, Nitrate+ Nitrite (10 mg/L) 1stQtr 3116/2005 NA <1.0 NA NA NA <0.1 12nd Qtr 5/25/2005 NA <1.0 NA NA NA <0.1 13rd Qtr 8/31/2005 <1.0 <1.0 3.2 <1.0 NA <0.1 ii !Ill Ill . ,'.'.'. ........ r:1''5�, .... l�i�l-----+------1 !! 12nd Qtr 6/27/2007 <1.0 <1.0 <1.0 <1.0 32 <1.0 l3rdQtr 8/15/2007 <1.0 <1.0 <1.0 <1.0 31 <1.0 l4thQtr 10/10/2007<1.0 <1�.�o __ _,_<�1�.o�---+-'<1�.o� 321,,n l1stQtr • 3/28/2008 <1.0 ·<1.0 <1.0 <1.0 3il<.1 i2nd Qtr 6/25/2008 <1.0 <1.0 <1.0 <1.0 29 <1.0 :.: ... �:........... 9/10/2008 <1.0 <1.0 <1.0 <1.0 30 <1.0
stQtr ••••• 1..Q��gg:-1}g. :1-g :�:g ...................... l·1ll �� =�-05
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 .Cltr 12/16/2009410,,,,,, n, ··---··················· 1<10 1<10 <1.0 35 <0.1 1stQtr •• ······;uf7f.!Q10I<1.0 'l<.111'.o'·····--··C
1
·<"1'."o··-··················· ·><1.0 38 <0:1� ----2nd Qtr 6/14/201 a <1.0 <1.0 <1.0 <1.0 32 <0.1 3rdQtr 8/16/2010 <1.0 <1.0 <1.0 <1.0 28 <0.1 4thQtr 10/15/2010 <1.0 1<1.0 <1.0 <1.0 24 <0.1 istaii ··-·212if.!oi1 <LO I<1.o <1.o • ••••• <1.o '· ------'4�04<"'0"-.1'--
2ndOtr 5/25/2011 <1.0 <1.0 <1.0 <1.0 31 <0.1 3rdQtr 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 (1) 1217/2011 <1.0 <1.0 <1.0 <1.0 .��. NA ,., ., __ , __ 12 <1.o <fO <1.0 <1.o 21 <0.1 Qtr ---6/22/2012 <1.0 _________ <1.o----<1]' ______ <1.0 ________ ---------32 <0.1 ----------
Qtr 9/5/2012 <1.0 <1.0 <1.0 <1.0 33 <0.1 �! · 1�l��l ·1t8-··-·· �}g · ·:t.g..... :t� �..... 34�� :g:� Qtr 6/18/2013 <1.0 <1.0 <1.0 <1.0 34.9 <0.1 Qtr 9/3/2013 <1.0 <1.0 <1.0 <1.0 33 <0.1
1st g1; 1 �i:�g:: :: g :ll ::: g :: g 35J :%12ndQtr 5/23/2014 <1.0 <1.0 <1.0 <1.0 39.7 <0.1 3rdQtr 8/26/2014 <1.0 <1.0 <1.0 <1.0 34 <0.1 fJ§:: 1����g�: :�:g ·:lJ ·:�:g -··· · ··· l·:1J··➔• ;t•l·:-&-:l··-2ndQtr 6/11/2015 <1.0 <1.0 <1.0 <1.0 35.8 <0.1 3rdQtr 9/9/2015 <1.0 <1.0 <1.0 <1.0 37.7 <0.1 1-:.g:r·· 1���g�: :�:g :�:g :�:g=-----+�·�g�-----+-------';::; :g:�, ______ ....,, Duplicate1W4-70 <1.0 <1.0 <1.0 <1.0 37.7 2nd Qtr 6/8/2016 <1.0 <1.0 <1.0 <1.0 36.4 <0.1 Duplicate TW4-70 3rdQtr 4thQtr 1stQtr ••• 2ndQtr 3rdQtr 4thQtr 1siair
<1.0 <1.0 <1.0 <1.0 37.7 <0.1 811912016 ,.<�1�.o _____ .....,_<1�.o�--<1.0 <1.0 35.7 <0.1 �.�i·lig� ·:tg �ti··· :� :g :� :g ��:� :g: � 6/21/2017 <1.0 <1.0 <1.0 <1.0 37.2 <0.1 8/8/2017 <1.0 <1.0 <1.0 <1.0 38.1 <0.1 1.����g� � :� :g · :tg":t·i· :� -� .................... ��1 l�� -
DuplicateTW4-70 <1.0 <1.0 <1.0 <1.0 39.3 <0.1 2ndQtr 6/14/2018 <1.0 <1.0 <1.0 <1.0 34.4 <0.1 3rdQtr 9/22/2018 <1.0 <1.0 <1.0 <1.0 41.2 <0.1 4thQtr 10 /29/2018 <1.0 <1.0 <1.0 <1.0 32.9 <0.1 1°"Si.Qfr"·--· ···3119f.2i:f19<1.o ....... <{o ···:c1.o <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 1stotr 311212020 <1.0 <1.0 <1.o <1.0 36. <·tH 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 4thQtr 11/4/2020 <1.0 <1.0 <1.0 <1.0 31.3 <0.1
e..,TW.=..,;s:ee...3,,./1,;;8""12"'02"1,f';:<<:,';:gs-----=�:g :{:§-· ............. ········-��:g ·���.: :�}·
TW4-75 2nd Qtr Duplicate TW4-75 3rdQtr Duplicate TW4-75 4thQtr 1s101r 2ndQtr 3rd Qtr 4thQtr 1,1aii 2ndQtr 3rd Qtr Duolicate TW4-75
<1.0 <1.0 <1.0 <1.0 37.4 <0.1 6/17/2021 <1.0 <1.0 <1.0 <1.0 35.8 <0.1 <1.0 <1.0 <1.0 <1.0 34.3 <0.1 9/23/2021 <1.0 <1.0 <1.0 <1.0 35.3 <0.1 <1.0 <1.0 <1.0 <1.0 35.5 <0.1 12/9/2021 <1.0 <1.0 <1.0 <1.0 35.8 <0.1 312212022 <1.0 •• <1."b <1.0 <1.0 28.6 <0.1 6/16/2022 <1.0 <1.0 <1.0 <1.0 26.9 <0.1 9/15/2022 <1.0 <1.0 <1.0 <1.0 37.2 <0.1 12/8/2022 <1.0 <1.0 <1.0 1<1 n 35.1 <0.1 ··313012023 ·<'f:-0-··· <1.0 <1.0 1<1.0 36.8 <0.1 6/16/2023 <1.0 <1.0 <1.0 <1.0 36.8 <0.1 9/26/2023 <1.0 <1.0 <1.0 <1.0 37.5 <0.1 <1.0 <1.0 <1.0 <1.0 37.6 <0.1 (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 NA:: not analyzed Shaded indicates concentrations exceeding GWQS
0.119
TABLE 1 (4 of 33)
Historic Summary Of Monitoring Well Analytical Results Up To The 3rd Quarter 2023
Chloroform Contamination Investigation
TW4-1(eNorolormpump,ogwen lllrted1n1/1'1115)
Sampling Event
1stQtr 3/16/2005
2nd Otr 5/25/2005
3rd Qtr 8/31/2005
4th0tr 12/7/2005
1stQtr 3/9/2006
2nd Otr 6/14/2006
3rd Qtr 7/20/2006
4thQtr 11/8/2006
1st0tr 2/28/2007
2ndQtr 6/27/2007
3rd Qtr 8/15/2007
41hQtr 10/10/2007
1st0tr 3/28/2006
2nd0tr 6/25/2008
3rd Qtr 9/10/2008
4th Ctr 10/15/2008
1st0tr 3Jff12009
2nd Qtr 6/23/2009
3rd Qtr 9/14/2009
4thQtr 12/29/2009
1st0tr 3/3/2010
2nd Otr 6/14/2010
3rd Otr 8/18/2010
4th0tr 10/15/2010
1st0tr 2/24/2011
2nd0tr 6/1/2011
3rd Qtr 8/18/2011
4th Cir 11/29/2011 1stOtr(!) ___ fi24i2oi2
2nd Otr ---6/14/2012
3rd Qtr 9/28/2012
4th Ctr 10/4/2012
1st0tr 2113/2013
2nd0tr 6/19/2013
3rd Qtr 9/3/2013
4thQtr 11/14/2013
1st0tr 2/5/2014
2ndQtr 5/23/2014
3rd Qtr 8/27/2014 4th Ctr ____ 10/29/2014
1s1Qtr(2l 3/9/2015
2nd0tr 6/8/2015
3rd Qtr 8/31/2015
4th Ctr 10/19/2015
1stQtr 3/9/2016
2ndQtr 5/23/2016
3rd Qtr 7/25/2016
4thQtr 10/13/2016
1st0tr 3/8/2017
2ndQtr 6/13/2017
3rd Otr 7/26/2017
4th0tr 10/11/2017
0w'o�Mf--..J'!e3.,r212�rs----6/8/2018
8/22/2018
10/22/2018
OWMRCsol11samole
1st0tr 3/8/2019
2nd Qtr 6/5/2019
3rd Qtr 9/4/2019
4th Qtr 12/10/2019
1stQtr 2/19/2020
2nd Qtr 5/27/2020
3rd Qtr 9/4/2020
41hQtr 10/28/2020
1stQtr 2/23/2021
2nd Otr 6/9/2021
3rd Qtr 8/24/2021
4th Qtr 12/1/2021
1st0tr 3/9/2022
2ndQtr 6/8/2022
3rd0tr 8/30/2022
4th Qtr 11/30/2022
1stQtr 317/2023
2nd Qtr 6113/2023
3rd0tr 8/9/2023
Carbon Tetrachloride
i5"g/L)
NA
NA
<10
<50
<50
<50
<50
1.4
1.2 1.4
1.3 1.3
1.3
1.1
1.3
1.3
1.1 1
<1.0
<1.0 <1.0 1.2
1
<1.0
<1.0
<1.0
<1.0
<1.0
·�1.0
<1.0 ----
<1.0
"<1.0
3.66
<1.0
<1.0
<1.0
5.47
4.77
<1.0
<1.0 _________
<1.0
<1.0
<1.0
<1.0
<1,0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<7.6
<1.0
<1.0
_________
<1.0
<1.0
<5.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
·:;1�0
<1.0
<1.0
Chloroform
(70 "gill
2.700
3.080
2,900
2.400
2,700
2,200
2,840
2.260
1.900
1.900
2.300
2.000
2.000
1,900
1.700 1.700
1.700 1.500 1.700
1.400 1,300
1.600
1,600 1.500
1.300
1,200
1.300
1,500 1,300
----1Jioo
1,000
1.100 1,320
1.100
1.150
1,280 1.090
1.020 845
____ 1.J:!.O 1,130 1,260
1.060
1,040 974
1.140 1.160
1,330 519
977
958
556
810
70.4 ----942
1.010
752
210
87.2
1,040
894
1.070
1,190
499
1,060
924
948
957
821
957
946 914
954
1,010
928
830 891
{ll, As of March 2012 both north and south wild Ide ponds no Ion!!!!'�� water_ {!l,TW4-1 converted lo achlorof001;!!)l;"'!e� welt started tn 1/14/15
J�chloroformpuffllJ\1'19.,!"""II TW4-41 started In M!)' 2018 __ _ NA : not analyzed
Shaded 1ndieatn concentratoos exceeding GWOS
Bold and Italics indicates the MOL exceeded the GWOS
J "ApproK1mated value
OUSA White Mesa Mill
Parameter
IGWQSI Chloromethane Methylene Chloride
130 ug/L) (5"g/L) NA NA
NA NA
<10 <10
<50 <50
<50 <50
<50 <50
<50 <50
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
c::1.0 <1,0
<1.0 <1.0
�1-.0 <1.0
<1.0 <1.0
<1.0 <1.0 <1.0 <1.0 <1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1,0
<1.0 <1.0 <1.0 <1.0
<""i.o------<1.0
<1,0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
1.4 <1.0
<j2_ ______ <1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0 <1.0
<1.0
<1.0
<1.0
<1.0
<12
<1.0 <1.0------
<1.0
<1.0
<5.0 <1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0 1.18
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0 ________
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
23 J
<1.0
<1.0 ----
<1.0
<1.0
<5.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0 <1.0
<1.0
<1.0 <1.0
1.1 <1.0
<1.0 <1.0
Chloride
No GWQS (mg/LI
NA
NA
NA
52
49
48
51
47
47
45
43
43
39
39
35
41 37
37
36
41 35
40
35
40
41
35
36
40 38
------42
39
40 37.6
39.1
37.6
36.5
38.9
37.4
38
Nitrate, Nitrate + Nitrite
•10mg/L) 9.1
10.6
9.8
9.7
9.4
9.6
9.2
8.9
9
8.4
7.8
• • 7.6
8.68 8.15 9.3 7.5
6.9
7.3
6.8
7.1
6.8
6.7
6.6 6.6
6.6 6.8
6.6 6.8
7.1
5.0
6.5
6.99
6.87
7.12
7.08
7.74
6.93
4.80
--------38.7 ___________ 6.31
38.3 7.06
40.3 6.07
45.9 6.28
38.5 1.55
41.7 0.148
44.4 0.138
44.7 5.49
44.2 0.746
41.5 444
41.8 5.74
42.8 5.04
38.5 5.78
42 0.17
45'.8 4.84
42.0 4.38
47.3 4.30
43.2 4.57
NA 0.46
40.9 4.51
44.8 1.43
46 1.65
44.2 3.91
47.5 4.67
46.4 0.44
43.7 2.22
41.9 4.30
45.4 2.72
37.2 0.73
44.8 1.38
45.5 4.37
42.6 3.90
45.5 0.18
45.1 0.42
38.3 3.62
43.8 1.71
42.5 3.87
44.6 3.83
TABLE 1 (5 of 33) Historic Summary Of Monitoring Well Analytical Results Up To The 3rd Quarter 2023 Chloroform Contamination Investigation OUSA White Mesa Mill
TW4•2 (cr11«o1orm pumpa'\g we11 atart,ngt/14115) Sampling Event Parameter IGWQSl
1st0tr 2ndQtr 3rd Otr 4thQtr 1stQtr 2ndQtr 3rd Otr 4th0tr 1stQtr 2nd0tr 3rdQtr 4th0tr 1st0tr 2nd Qtr 3rd0tr 4thQtr
Carbon Tetrachloride (5uo/Ll Chloroform Chloromethane Methylene Chloride Chloride Nitrate, Nitrate+ Nitrite (70 "oil) 130 ua/Ll (5 "oil) No GWQS (moil) (10 mg/L) 3/16/2005 NA 3.700 NA NA NA 7.7 5/25/2005 NA 3.750 NA NA NA 8.6 8/31/2005 3,900 <10 NA 8.0 12/7/2005 3,500 56 7.8 3/9/2006 3,800 56 7.5 6/14/2006 3,200 56 7 .1 7/20/2006 4,120 54 7.4
----�:����1-------'�"'!c1 ;��� -�H :; � ;! ;� 6/27/2007 2.5 3,000 <1.0 <1.0 50 7.8 8/15/2007 2.2 340 <1.0 <1.0 49 7.3 10/10/2007 2.1 3.200 <1.0 <1.0 51 6.9 3/28/2008 2.3 3,300 -;;·ro <1.0 48 6.9 6/25/2008 2.2 3,100 <1.0 <1.0 46 7.4 9/10/2008 2.4 2.800 <1.0 <1.0 42 7.1 10/15/2008 NA #N/A NA NA 47 8.0 11/18/2008 2.4 3.200 <2.0 <2.0 NA #NIA 1stQtr 3/11/2009 2.2 3.100 <1.0 <1.0 46 6.5 2nd Ctr 6/23/2009 2 2.800 <1 .0 <1.0 44 6.4 3rdQtr 9/14/2009 2 3.000 <1.0 <1.0 43 6.6 4th0tr 12/29/2009 2 1.600<1.0 <1.0 46 6.4 1stQtr 3/3/2010 2 2.600 <1.0 <1.0 42 6.8 2nd Ctr 6/14/2010 2.6 3.300 <1.0 <1.0 43 8.7 3rd Otr 8/18/2010 2.5 3,300 <1.0 <1.0 43 6.6 4th0tr 10/15/2010 2.1 3.000 <1.0 <1 .. _0�------+------41 6.5 1st Qtr 2/24/2011 2.4 3.100 <1.0 :.Z1.o 46 --~·····:ro 2nd Qtr 6/2/2011 2.2 3.000 <1.0 <1.0 42 6.8 3rd Qtr 8/17/2011 1.6 2.400 <1.0 <1.0 48 6.0 4thQtr 11/29/2011 2.8 3.900 <1.0 <1.0 49 ___ },Q 1st0tr(2) 1/24/2012 "2" 2,500 <1.0 <1.0 49 7.1 2nd0tr ---6/14/2012 2.1 ---2.500 <1.0___ <1.0 -----------52 7.7 3rd Otr 9/4/2012 1.8 2,900 <1.0 <1.0 76 4.0 4th0tr 1014/2012 2 3.100<1.0 <1.0 49 7.6 1stQtr 2/13/2013 5.17 3.580 <1.0 <1.0 46 8.1 2nd0tr 6/19/2013 2.65 3.110 2 <1.0 46.9 7.51 3rd Qtr 9/3/2013 2.41 3,480 <1.0 <1.0 44.9 9.3 4th Qtr 11/14/2013 3.15 3.740 <1.0 <1.0 43.9 8.39 1st0tr 2/6/2014 71 3.180<1.0 <1.0 45.9 7.87 2nd Otr 5/23/2014 6.05 2.930 <1.0 <1.0 45.4 9.11 3rdQtr 8/27/2014 1.4 3.170 3.6 <1.0 45 6.2 4th Qtr 10/30/2014 2.6 3,580 <1.0 <1.0 45.5 8.45 1stQtr(2) ---3/9/2015 1.44 -1.840 <1.0 <1.0 44.9 5.32 2nd Qtr 6/812015 <1 .0 1.650 <1.0 <1.0 48.1 4.3 3rdQtr 8/31/2015 <1.0 1.060 2.6 <1.0 50 3.76 4thQtr 10/19/2015 2.6 2.070 <1.0 <1.0 41.9 5.18 1st Otr 3/9/2016 1.2 1.970. �;·:o <1.0 43.4 5.30 2nd Ctr 5/23/2016 1.49 2.070 <1.0 <1.0 43.8 5.67 3rdQtr 7/25/2016 <1.0 1,780 <1.0 <1.0 42.9 4.07 4th Ctr 10/12/2016 <1.0 1.600 <1.0 <1.0 44.3 6.07 1st Ctr 3/8/2017 <1.0 1.570 <1.0 <1-�o 43.f 4.74 2nd Qtr 6/H/2017 <1.0 1.940 <1.0 <1.0 43.6 4.90
3rd Qtr 7/26/2017 <1.0 1.310 <1.0 <1.0 43.2 5.08 4th0tr 10/11/2017 <1.0 1.610 <1.0 <1.0 43.5 3.25 OWMRC split sample <19 1.200 <30 68 J 44 4.00 �P.!1tateTW4-50 <19 1.200 <30 60 J 43 5.00 1st Qtr 3/12/2018 <1.0 764 <1.0 <1.0 44.4 2.94 2nd0tr 6/812018 <1.0 949 <1.0 <1.0 41.3 3.50 3rd Qtr 8/22/2018 <1.0 980 <1.0 <1.0 44.3 4.83 4th Qtr 10/22/2018 <1.0 822 <1.0 <1.0 41.7 3.52 1stQtr 3/8/2019 <1.0 1.040 <1.0 <1.0 40.4 3.92 2nd Qtr 6/5/2019 <1 .0 1.360 <1.0 <1.0 39.8 4.38 3rdQtr 9/412019 <1.0 797 <1.0 <1.0 40.8 4.79 4thQtr 12/10/2019 <1.0 934 <1.0 <1.0 41.5 3.40 1st Ctr 2/1912020 <1.0 1.880 <1.0 <1.0 42.1 6.07 2nd0tr 6/10/2020 <1.0 1.070 <1.0 <1.0 40.6 3.62 3rdQtr 9/4/2020 <1.0 1.260 <1.0 <1.0 41.3 3.35 4th0tr 10/28/2020 <1.0 1.130 <1.0 <1.0 38.7 2.34 1st Otr 2/23/2021 <1.0 939 <1.0 <1.0 43.3 3.30 2ndQtr 6/9/2021 <1.0 1,160 <1.0 <1.0 32.5 3.89 3rd0tr 8/24/2021 <1.0 1.150 <1.0 <1.0 36.8 1.97
1.�;� :�:� :}9=-o-----+------'ci�=':�=+-------"'3"'3�"j; 2nd Otr 6/8/2022 <1.0 892 <1.0 <1.0 39.5 3.1 3rd Qtr 8/30/2022 <1.0 832 <1.0 <1.0 40.7 3.07 4thQtr 11/30/2022 <1.0 1.030 <1.0 <1.0 35.5 3.74 1stQtr 3{7/2023 <1.0 772 <1.0 <1.0 41.4 2.03 2ndQtr 6/13/2023 <1.0 788 1.2 <1.0 38.1 3.7 3rdQtr 8/9/2023 <1.0 867 <1.0 <1.0 41.2 3.23 J!l ������11_�h north and south wild lrfe ponds__no_lonQ!J �e<:eMf12. water_ (2) TW4-2 and TW4-11 convel1ed 10 a chlorofonn _pumP.-Jii wel started in 1114/15 _ NA and #NJA(for graph use)= not analyzed Shaded indicates concentrations exceeding GWOS. Bold and italics ind1tate1 the MOL exceeded the GWOS. J "' ApprolOmaled value
TABLE 1 (6 of 33) Historic Summary Of Monitoring Well Analytical Results Up To The 3rd Quarter 2023 Chloroform Contamination Investigation
DUSA White Mesa Mill
TW4-3 Sampling Event Parameter
tGWQSI Carbon Tetrachloride Chloroform Chloromethane Methylene Chloride Chloride Nitrate, Nitrate+ Nitrite
(5 pg/L) (70 """' (30 pg/L) (5 pg/L) No GWQS (mg/L) (10 mo/LI
1stQtr 3/16/2 005 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 4thQtr 12fl�l2."'0"'0"5+-<�1=.0 ______ 4<_1�.0�----<� . .L.P....... <1.0 ................. 2E " i"siofr·· • • ··31912006 <1.0 <1.0 2.3 <1.0 2i ' 3. 2ndQtr 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 4lhQtr 11/8/2006 <1.0 <1.0 <1.0 <1.0 231-------1.5
1statr :ii:28/2001 ·<-.LO -c:ro <1.0 ·<1.0 :i2 3.1 2nd Qtr 612.7/2007 <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 10�=:��=t�r --�1cs��'=1 -='��7gesgee�+-:---;;.csg-----------<-:;�g�--+-:---;;.cs:g--------+·JH �; }: 2nd Qtr 6/2 5/2008 <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 4lhQtr 10/15/2008 <1.0 <1.0 <1.0 <1.0 22 _____ 2.6
1stQtr 3/4/2009 <fi'i____ <1.0 <fii <1.0 21 2:s 2nd Qtr 6/2 3/2009 <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 4lhQtr 12/29/2009 <1.0 <1 .0 <1.0 <1.0 22 2.6
1statr 212312010,-<"""'1""'.o------➔<fli •••••••

•
•
•
•
•
•
•

•
•
<LO <i.ii 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 4thQtr 1011s12010 <1.0 <1.0 ........ _ _,_<�1�.o� ___ _,<�1�.o�.... 26 3.3
1stQtr 2/15120"-rf <1.0 <1.0 <1.0 <1.0 23 'i5 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 4lhQtr ............... 11/14/2911. .<.LQ.. <1.0 <1.0 <1.0 ____ 23 .4 .• 4 lst0tr(2) 1/17/2012 <1.0 <1.0 <Lil <1.0________ _________ 21 ___________ 7.1 2nd Ctr ---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 1:&: 1��ga :; g �; g :; g :; g _ __,____ 2i� 5�: 2nd Qtr 6/2 8/2013 <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 4th Qtr 11/8/2013 <1.0 <1.0 <1.0 <1.0 24.1 5.89 "fSi"Qtr...... ···
1/22/2Cf14. <1.0 '<"fcf" <1.0 <1.ci 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 1!&: 1�i�ilHll :;g :;g :;g •········-··--·-····--·· �H··· :il 2nd Qtr 6/10/2015 <1.0 <1.0 <1.0 <1.0 27.5 5.71 Duplicate1W4-65 <1.0 <1.0 <1.0 <1.0 27.5 3.94 3rdQtr 8/13/2015 <1.0 <1.0 <1.0 <1.0 27.4 3.88 t:&: 1�i!�,�g�;:'-+--:;�g�------>�l'.g :;g JH �I� ;:�� 2nd Qtr 5/25/2016 <1.0 <1.0 <1.0 <1 .0 27.9 5.65 !: &:; 1�i��g;: *·:: g :;:g :; g �:; :�g
1stQtr 3/14/2017 <1.0 <1.0 <1.0 <1.0 2"ii:"1 6.18 2ndQtr 6/14/2017 <1.0 <1.0 <1.0 <1 .0 28.7 6.36 3rdQtr 7/27/2017 <1.0 <1.0 <1 .0 <1 .0 28.5 6.36 Duplicate TW4-65 <1.0 <1.0 <1.0 <1.0 28.9 6.24 1��:g: ....................... 1�;!��;� :�:g :11 :�:g :�:g ··················· ... " ........ " ·�!::.... l¾® Duplicate1W4-65 <1.0 <1.0 <1.0 <1.0 29.5 6.31 112ndQtr 6/8/2018 <1.0 <1.0 <1.0 <1.0 26.1 6.52 3rdQtr • 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 ll4thQtr 11/30/2018 <1.0 <1.0 <1.0 <1.0 27.4 5.85
�:a:·�4-65 ... 3h3120·1·e ·:}:g ·... :� :g =�:g ... ...
. --·:l'.g ��·:·�--·..... l�� 2ndQtr 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 3rdQtr 9/11/2019 <1.0 <1 .0 <1.0 <1.0 26.0 5.12 Duplicate TW4-65 <1 .0 <1.0 <1.0 <1.0 22.1 5.76 �:&:; 1�;�g�� :;g ---1-:�;�g�-_...�rn-• �ig • i;:�! Duplicate 1W4-65 2ndQtr Duplicate TW4-65 l3rdQtr l4thQtr lfiiiatr [Duplicate TW4-65 l2ndQtr [Duplicate TW4-65 l3rdQtr I Duplicate TW4-65 l4lhQtr TW4-65
NA=notanalyzed
<1.0 <1.0 <1.0 <1.0 26 6.38 6/10/2020 <1.0 <1.0 <1.0 <1.0 26.2 6.53
<1.0 <1.0 <1.0 <1.0 26.7 6.63 9/17/2020 <1.0 <1.0 <1.0 <1.0 25.9 6.36 11/4/2020 <1.0 <1.0 <1.0 <1.0 24.9 6.02 311112021 <1.o <1.o <1.0 ··�1.0 ••• ··········2sX·· 6.19 <1.0 <1.0 <1.0 <1.0 27.6 6.64 6/15/2021 <1.0 <1.0 <1.0 <1.0 27 8.04 <1.0 <1.0 <1.0 <1.0 23.9 7.89 9/15/2021 <1.0 <1.0 <1.0 <1.0 20.3 5.28 <1.0 <1.0 <1.0 <1.0 20.7 6.19
12/7/2021 <1.0 <1.0 <1.0 <1.0 26.2 5.97
3/15/2022 :·�)=:g�------+-:�:g :�:g ::�.� ·····-------'�ti -----66�16/15/2022 <1.0 <1.0 <1.0 <1.0 26.7 5.8 9/13/2022 <1.0 <1.0 <1.0 <1.0 27.3 5.47
11/30/2022 <1.0 <1.0 <1.0 <1.0 l················································ 21.! 6.64 31.2212023 <ro.... <1.0 <1.0 <1.0 ... :it>:1 6.1 6/15/2023 <1.0 <1.0 <1.0 <1.0 23.5 6.4 9/13/2023 <1.0 <1.0 <1.0 <1.0 26.9 6.40
Shaded indicates concentrations exc eedinR GWQS.
TABLE 1 (7 of 33)
Historic Summary Of Monitoring Well Analytical Results Up To The 3rd Quarter 2023
Chloroform Contamination Investigation
TW4-4 (chlorotoon pumpr,g we1
11..-«1.,111q1r2010l
Sampling Event
1st0tr 3/16/2005 2nd Qtr 5/25/2005
3rdQtr 8/31/2005
4th Qtr 12/7/2005
1st0tr 3/9/2006
2nd Otr 6/14/2006
3rd0tr 7/20/2006
4th Qtr 11/8/2006 1st Ctr 2/28/2007 2nd Qtr 6/27/2007 JrdQtr 8/15/2007 4thQlr 10/10/2007 1st Ctr 3/28/2008 2ndQtr 6/25/2008
3rd Qtr 9/10/2008 4th Qtr 10/15/2008
1st0tr 11/18/2008 1stQtr 3/4/2009 2nd Qtr 6/23/2009
3rd Qtr 9/14/2009 4th Qtr 12/29/2009
1stQtr(2) 2/1712010
2nd Qtr 6/14/2010
3rd Otr 8/10/2010 4thQlr 10/15/2010
1st0tr 2/23/2011
2nd0tr 6/1/2011 3rd Qtr 8/17/2011
4thQtr 11/16/2011 11StQtrl1) 1/23/2012
2nd Qtr ----6/6/2012 3rd Qtr 9/4/2012 4thQtr 10/3/2012 1st0tr 2/11/2013 2ndQtr 6/29/2013
3rd Qtr 9/3/2013 4thQtr 10/23/2013 1stQtr 1/27/2014
2ndQtr 5/19/2014 3rd Qtr 8/11/2014 4th Qtr 10/21/2014 1st Otr (4) ---3/9/2015 2nd Ctr 6/10/2015
3rd Otr 8/31/2015 4th Qtr 10/19/2015 1st0tr 3/9/2016
2nd Ctr 5/23/2016 3rd Qtr 7/27/2016
4th0tr 10/13/2016 .fSIOtr 3/8/2017
2nd Ctr 6/13/2017 3rd Ctr 7/26/2017
fil__Qtr 10/11/2017 1 s1 Qtr 3/12/2018
2ndQtr 13) -6/8/2018
3rd Qtr 8/22/2018 4th Qtr 11/28/2018 1st0tr 3/8/2019 2nd0tr 6/5/2019 3rdQtr 9/4/2019 4th Otr 12/10/2019
:;·statr 2/19/2020 2nd Qtr 5/27/2020
3rdQtr 9/4/2020 4th Otr 10/28/2020
1st Ctr 2/23/2021 2nd Qtr 6/9/2021
3rd Ctr 8/24/2021 4thQtr 12/1/2021
1st0tr 3/9/2022
2nd Qtr 6/8/2022 3rd Ctr 8/30/2022
4thQtr 11/30/2022
1s1·atr 317/2023
2nd Otr 6/13/2023 3rd Ctr 8/9/2023
Carbon Tetrachloride
µ9/L)
NA
NA
1.7 1.5
1.7 1.5 1.5 1.6 1.5 1.4
NA <2.0 1.2 1.2 1.1 1.1 ----------1
1.2
1.3 1.3
1.4 1.2 <1.0 1 <1.0
<1.0 ----1.2 1 1 <1.0 1.2 5.3
3.88 4.94 4.94
<1.0 1.05 <1.0 <1.0 <1.0 <1.0
<1-.0--� <1.0 <1.0 <1.0 <1.0 <1.0
<1.0------
<1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <l.O
-�1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0
Chloroform
170 un/L) 3,100
2,400 3,200
2,800
2,900
2,600
2,850
2,670 2,200 2.400 2,700 2,500 2,800 2,500 2,200 #N/A 2,500
2.200 1,800 2,000 950
----1)00
1.700 2,100 1.700 1,800 1.700 1,500 1,500 1,200
----1100 1.600 1.400 1.460 1,330 1,380 1.360 1,260 1,220 1,320 1,130
1,280 1,220 1,190 1,190 1.780 1,380 1.430 1.290 1,290 1,290 1,120 1,160
1,030 1,140 1.050
1,070 989 1.140 1.100 1,140 1,110 979 1,130 1,240 1,100
950 1,010 1.110 1,040 1030 945 1,980 1 020
j1) As of March 2012 both north and south w,ld �le ponds no� recelYlni. water. (21 TW4-4 converted to a Chlorof()(m pum,.F.!Q)':'8H stared 1r1 1&L� 2010 ____ _
(3lTW◄-41 imtalledasaChlorof()(mpu�;:veHstaredinM,!.YJ018 ____ _
J�TW◄--2convertedtoachlorofom;!�welstarted.-. 1114115 _____ ,. NA and #N/A(f()( graph use) "-not analyzed
Shaded indicates conce ntratoo& exceeding GWQS
Bold and italics indicates the MDL exceeded the GWOS.
OUSA White Mesa Mill
Chloromethane
130 µg/L)
NA NA <10
<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
<TO ______ <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0
Parameter
IGWQSI
Methylene Chloride
15 gill
NA
NA
<1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0
NA <2.0 <1.0 <1.0 <1.0 <1.0
<1.0 -----
<1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0
<1.0 ----
<1.0 <1.0 <1.0 <1.0 <1.0 <1.0
<1.0 <1.0 7.1 <1.0 <1.0
<1.0------<1.0 1.72
<1.0 <1.0 <1.0
<f""o--
<1.0 <1.0 <1.0 <1.0
<1.0 ______ <1.0 <1.0 <1.0
<1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0
<1.0
<1.0 <1.0 <1.0
<1.0
<1.0 -----<1.0
<1.0 <1.0 <1.0 <1.0 � <1.o <1.0 <1.0 <1.0 <1.0 <1.0
<1.0 -----
<1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 1.9 <1.0 <1.0 <1.0
Chloride Nitrate, Nitrate+ Nitrite
No GWQS lma/L) 110ma/L)
NA 10 0
NA 11.3
NA 9.9
54 10 2
51 9.5
48 8.6
50 9.7
49 10 1 49 9.0 47 9.4
45 9.5
47 9.5 43 9.2 42 10 8 39 8.8 44 10 1
NA #N/A 37 10 2 34 8.2 39 8.4 41 7.6 ---------48 6.6
35 7.6
36 7.3 38 7.1
41 7.0
35 7.0
40 6.6
39 7.0 38 7.1 --43 ----------7,1
39 7.1
38 7.0 39 7.36
39.6 6.30 38.8 7.22
43.9 7.84
37.4 7.28 47.5 5.91
40 5.3
40 7.02
37.6 7.7
41.3 6.33
45.8 6.45
38.5 6.27 39.7 6.7
41.9 6.56 40.2 --7-.22
45:3 6.77
41.7 6.87
40.7 7.06
40.5 6.47
40.7 6.90 42.2 6.12
39.0 6.34
44.6 6.10
41.4 6.02
38.3 7.26
38.5 10 40
39.4 6.32
40.4 6.52
43.4 4.58
46.1 7.26
40.0 7.04
38.6 6.77
398 5)5 39.4 9.02
39.6 4.00
42.5 7.32
37.1 6.6 39.9 6.0
41.0 6.65
29.6 6.59
3ci:2 39.7 6.28
40.6 6.08
TABLE 1 (8 of 33) Historic Summary Of Monitoring Well Analytical Results Up To The 3rd Quarter 2023 Chloroform Contamination Investigation DUSA White Mesa Mill
TW4-5 Sampling Event Parameter IGWCSI Carbon Tetrachloride 15 ug/L) Chloroform Chloromethane Methylene Chloride Chloride Nitrate, Nitrate+ Nitrite (70 µo/L) 130 ua/L) 15 ua/L) No GWCS Ima/LI (10 mo/L) 1st Ctr 3/16/2005 NA 120 NA NA NA 4.92nd Ctr 5/25/2005 NA 113 NA NA NA 3.7 3rd Qtr 8/31/2005 <2.5 1__ 82 5.8 <2.5 NA 6.0 4th Otr 12f?EQ� �2.5 63 2.5 <2.5 56 6.0 1st Ctr 3/9/2006 <2.5 66 3.1 <2.5 52 6.0 2nd Qtr 6/14/2006 <2.5 51 3.1 <2.5 51 5.9
3rd Ctr 7/20/2006 <1.0 53.7 <1.0 <1.0 54 6.7 4th Ctr 11/8/2006 <1.0 47.1 <1.0 <1.0 55 2.9 1·st"Otr 212at.2001 <1.0 35 <1.0 <1.0 57 7.8 2nd Qtr 6/27/2007 <1.0 26 <1.0 <1.0 45 7.0 3rd Ctr 8/15/2007 <1.0 9.2 <1.0 <1.0 38 7.7
ie��:h�tg;:�;---1�������=gg'-';+:�i�:g�-----<e---�9,�·�·•-:t��----t-:�i�:g-----+------����-1-------��=:� 2nd Qtr 6/25/2008 <1.0 9.3 <1.0 <1.0 37 8.7 3rd Ctr 9/10/2008 <1.0 11 <1.0 <1.0 34 7.94th Qtr 10/15/2008 <1.0 10 <1.0 <1.0 37 9.3 1st0tr 3/4/2009 <1.0 12 <1.0 <1.0 34 7.92nd Otr 6/23/2009 <1.0 13 <1.0 <1.0 37 7.5
3rd Otr 9/14/2009 <1.0 12 <1.0 <1.0 48 8.3 4th Ctr 12/29/2009 <1.0 8.5 <1.0 <1.0 41 7.5 1st0tr 2/25/2010 <1.0 13 <1.0 <1.0 43 6.8 2nd Qtr 6/14/2010 <1.0 12 <1.0 <1.0 28 7.1 3rdQtr 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 stQtr 2/22/2011 <1.0 10 <1.0 <1.0 34 7.0 Qtr 5/26/2011 <1.0 9 <1.0 <1.0 35 7.2 Otr 817/2011 <1.0 10 <1.0 <1.0 37 7.5 Ctr 11/16/2011 NA #N/A NA NA 30 6.0 11\ 12/7/2011 <1.0 7.9 <1.0 <1.0 NA #N/A •• ,"m"1l,."1/�-,",;-;18"12"'0"'12atc<;-'1.;;-0------+--�7�.6ar::<;-'1.;;-0----t:<cc1';a.O------t-··--· 22 5.8 datr ----61612012 <1.0 -------8.4 <1.0 ______ <1.0 ------------39 8.o Otr 9/11/2012 <1.0 12.0 <1.0 <1.0 37 8.1 Qtr 10/4/2012 <1.0 8.0 <1.0 <1.0 38 7.7 Qtr 2/13/2013 <1.0 10.8 <1.0 <1.0 34.3 8.24 dCtr 6/13/2013 <1.0 11.2 <1.0 <1.0 36.5 10.70 3rdQtr 9/5/2013 <1.0 11.6 <1.0 <1.0 39.1 7.79
4th0tr 11/13/2013 <1.0 14.4 <1.0 <1.0 41.1 7.75 1st0tr 1/30/2014 <1.0 12.5 <1.0 <1.0 40.5 9.16 2ndQtr 5/22/2014 <1.0 13.4 <1.0 <1.0 51.4 7.78 3rdQtr 8/14/2014 <1.0 12.0 <1.0 <1.0 44 7.2
4th Otr 10/13/2014 <1.0 14.6 <1.0 <1.0 45.1 8.31 1st0tr 3/12/2015 <1.0 13.8 <1.0 <1.0 45.1 9.32 OuplicateTW4-70 <1.0 13.8 <1.0 <1.0 46.4 8.81 2nd Ctr 6/10/2015 <1.0 13.3 1.07 <1.0 47.3 7.08
3rd Ctr 9/10/2015 <1.0 12.9 <1.0 <1.0 52.2 8.1 ,a•�1th�C�t�r __ �1�0�/28/2015 ..::.1'-'.o'------l---'1'-'1"'.o+<'-'1-".o'----+::-<1"".o'------+------"'43.6 8.03 1stQtr 3/17/2016 <1.0 11.0 <1.0 <1.0 44-:-i 10.2 2nd Ctr 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 8.494th Ctr (3) 10/26/2016 <1.0 9.9 <1.0 <1.0 47.8 8.32 Duplicate TW4-75 <1.0 1S101r----311512011 <1.0----12.0 <1.0 <1.0 49.5 8.34 12.6 <1.0 <1.0------44.7 8.492nd Otr 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
tr Ctr tr
10/11/2017 <1.0 sPid sample <0.19
3/12/2018 <1.0 6/13/2018 <1.0 8/30/2018 <1.0
13.8 <1.0 <1.0 42.5 8.57 12 <0.3 <0.32 47 8.6 15.2 <1.0 <1.0 51.2 8.36 13.9 <1.0 <1.0 47.3 9.24 15.4 <1.0 <1.0 54.7 7.34 ateTW4-70 <1.0 tr 11/28/2018 <1.0 15.3 <1.0 <1.0 55.9 7.28 15.6 <1.0 <1.0 49.8 7.67 TW4-70 <1.0 3/16/2019 <1.0 6/13/2019 <1.0 9/11/2019 <1.0 TW4-70 <1.0 12/14/2019 <1.0
16.2 <1 .0 <1.0 48.5 7.80 14.1 <1.0 <1.0 47.6 7.38 15.8 <1.0 <1.0 49.3 7.62 14.6 <1.0 <1.0 46.1 7.04 13.6 <1.0 <1.0 45.8 6.8915.7 <1.0 <1.0 53.1 6.97
'-'TW=••e,?0'-,3-/1�7/2=02�0+:°')"':�'-------e---;"'::-� =�:� :�:� !�:i �:�� TW4-70 Ctr Ctr Ctr 1st0tr l2ndCtr 13rd Ctr 14th Ctr 1st0tr l2ndCtr l3rdCtr
<1.0 14.8 <1.0 <1.0 48.4 7.72 6/11/2020 <1.0 15.4 <1.0 <1.0 49.5 7.83 9/18/2020 <1.0 14.8 <1 .0 <1.0 47 .0 6.37 �;;:���� �-!"'=-�------+---;H :; � :; � 5.94! �!� 6/16/2021 <1.0 13.0 <1.0 <1.0 50.6 6.11 9/22/2021 <1.0 11.2 <1.0 <1.0 39.6 6.63 12/6/2021 <1.0 12.4 <1.0 <1.0 51.3 6.71 3/23/2022 <1.0 11.0 <1.0 <1.0 47.7 7.3 6/16/2022 <1.0 ,0.3 <1.0 <1.0 40.7 7.1 9/14/2022 <1.0 13.2 <1.0 <1.0 45.8 7.22 12/8/2022 <1.0 7.6 <1.0 <1.0 51.8 7.74
3/29/2023 <1.0 8.6 <1.0 <1.0 51.3 6.3 6/2112023 <1.0 8.1 <1.0 <1.0 52.5 7 .1 9/14/2023 <1.0 9.1 <1.0 <1.0 50.5 8.83
<1.0 8.8 <1.0 <1.0 53.2 8.10
;
TW�70
(1) voe a were r8$11mpled because laboratory missed holdmg 1,me.
(� As of March 2012 both� and south wild 11� �longef rec�� waler. (�ehloroform_eornptnq_well 4-39statted.,11 _16 ___ • NA and #N/A(for i:iraphs) • not analvzed
Shaded mdicate& concen!rahons exceedJnQ GWQS.
TW4-6 Sampling Event
TABLE 1 (9 of 33) Historic Summary Of Monitoring Well Analytical Results Up To The 3rd Quarter 2023 Chlorofonn Contamination Investigation
Carbon Tetrachloride
15 ua/L)
OUSA White Mesa Mill
Parameter IGWCSI Chlorofonn Chloromethane Methylene Chloride Chloride 170 ug/L) (30 ug/L) (5 µg/L) No GWCS Ima/LI Nitrate, Nitrate+ Nitrite (10 mg/L) 1st Ctr 3/16/2005 NA <1.0 NA NA NA 0.2 2nd Ctr 512512005 NA 2.5 NA NA NA 0.4 3rd Qtr 8/31/2005 <1.0 10 2.8 <1.0 NA 0.8 4th Ctr 12/712005 <1.0 17 1.3 <1.0 32 0.9 1stQtr 3/9/2006 <1.0 31 <1.0 <1.0 31 1.2 2nd Otr 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 0.6 4th Ctr 11/812006 <1.0 42.8 <1.0 <1.0 65 1.4 1s!Qtr 2/28/2007 <-1":0 46 <1.0 <1.0 32 1.8 2nd Otr 6/2712.007 <1.0 11 <1.0 <1.0 38 0.6 3rd Otr 8/15/2007 <1.0 18 <1.0 <1.0 36 0.7 4th Ctr 10/10/2007 <1.0 18 <1.0 <1.0 35 0.8 1st Ctr 3/28/2008 <1.0 52 <1.0 <1.0 33 1.1 2nd Otr 6/25/2008 <1.0 24 <1.0 <1.0 35 0.9 3rdQtr 9/10/2008 <1.0 39 <1.0 <1.0 35 1.1 "'��"c�-=gc':;--�10"-�1"',1"'�"'�"'��ct-c:�"':�a--------t----r.c:;ct-c:�"':�a-------1-::0"�:�"----------1-------"'�;"-l---------"�:"l�1 2ndQtr 6/23/2009 <1.0 _ 120 <1.0 <1.0 37 2.7 3rdQtr 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 1st0tr(5) 2/25/2010 <1.0----------,ooo <1_0 ______ <1.0 --------------45 1.8 2nd Qtr 6/14/2010 <1.0 590 <1.0 <1.0 33 2.5 3rdQtr 8/11/2010 <1.0 630 <1.0 <1.0 31 3.9 4th Ctr 10/1512010 <1.0 420 <1.0 <1.0 41 4.3 1stQtr 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 3rd0tr 8n/2011 <1.0 16 <1.0 <1.0 39 0.3 4th Qtr 11/16/2011 NA #NIA NA NA 36 0.8 (1) 12/712011 <1.0 21 <1.0 <1.0 NA #NIA
Ts mfr14�----1:::���:� ::� �� ::� 11'=•�-------1--------'i"'-�-1--------'�"'•�II 2nd Ctr ----6/612012 <1.0 ---4.7 <1.0 <1.0 --------------40 0.2 3rdQtr 9/11/2012 <1.0 6.9 <1.0 <1.0 21 0.1 4th0tr 10/4/2012 <1.0 9<1.0 <1.0 41 0.2 1st0tr 2/13/2013 <1.0 6.89 <1.0 <1.0 40.4 0.2 2nd Qtr 6/13/2013 <1.0 4.86 <1.0 <1.0 37.9 0.2 3rd0tr 9/5/2013<1.0 5.93<1.0 <1.0 40.6 0.2 4th0tr 11/13/2013 <1.0 5.51 <1.0 <1.0 40.2 1.5 1stQtr 1/29/2014 <1.0 5.7 <1.0 <1.0 40.6 0.2 2nd Qtr 5/22/2014 <1.0 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 4th0tr 1012912014 <1.0 723 <1.0'------+=-<1"".o�------1------=41.1 6.9 1st0tr 3/12/2015 <1.0 1.180 <.,Lb <1.0 41.2. 5.3 2nd Qtr 6/10/2015 <1.0 1,040 <1.0 <1.0 41.6 5.9 3rdQtr 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 1st0tr 3/22/2016 <1.0 834 �;·.·o <1.0 42.3 6.79 2nd Qtr 6/8/2016 <1.0 486 <1.0 ___ <1.0 44.1 3.19 3rd0tr �016 <1.0 433 <1.0 <1 0 !----_-_-_-_-_-_ 42.2__ -3-.85
2nd0tr 6/21/2017 <1.0 239 <1.0 <1.0 42.6 2.42 3rd0tr 8/8/2017 <1.0 129 <1.0 <1.0 42.9 1.71 4th0tr 10/11/2017 <1.0 121 <1.0 <1.0 37.6 1.71 1st0tr 3/20/2018 <1.0 159 <1.0 <1.0 43.1 1.96 2ndCtr(6) 6/1412018 <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 Ctr 12/1212018 <1.0 37.0 <1.0 <1.0 20.0 0.90 1st0tr 3119/2019 <1.0 23.2 <1.0 <1.0 41 0.755 2nd0tr 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 'fSt'atr 311112020 <1.0 6.93 <·1�6 <1.0 43.2 0.222 2ndQtr 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 4thQtr 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 2ndQtr 6/16/2021 <1.0 2.9 <1.0 <1.0 43.8 0.215 3rd Qtr 9/15/2021 <1.0 3.71 <1.0 <1.0 34.1 0.166 4th Otr 12/8/2021 <1.0 3.92 <1.0 <1.0 44.8 <0.100 1stQtr 3/22/2022 <1.0 3.10 <1.0 <1.0 31.5 OJ 2nd Ctr 6/16/2022 <1.0 2.1 <1.0 <1.0 43.1 0.21 3rd0tr 9/14/2022 <1.0 3.90 <1.0 <1.0 38.7 0.144 4th Ctr 12/812022 <1.0 1.50 <1.0 <1.0 40.7 0.134 1st0tr 3/29/2023 <1.0 1.70 <1.0 <1.0 43.2 <0.1 2nd Ctr 6/20/2023 <1.0 2.3 <1.0 <1.0 44.7 0.13 3rd Qtr 9/14/2023 <1.0 2.6 <1.0 <1.0 44.0 0.170 (1) voes were resampled because laboratory missed holding time (2) Results of lhe TW4-70 lhe duplicate sample for TW4-6. (3) Reanalyzed for voes only. (� As of March 2012 both north and south wild life ponds �longer �ecerMg_water _ (�Chloroform_poo,9wellTW4-4stated in1st_gtr2()10 __ _ (� Chloroform J"'J!IP.!."i. well TW4-41 installed M� 2018 ___ • NA and #N/A(fOI' graphs) :: not analyzed Shaded indicates concentratlOnS exceeding GWOS.
TABLE 1 (10 of 33) Historic Summary Of Monitoring Well Analytical Results Up To The 3rd Quarter 2023 Chloroform Contamination Investigation DUSA White Mesa Mill
TW4-7 Sampling Event Parameter •GWQSI
1stQtr 2nd Qtr 3rdQtr 4th Ctr 1s1Qtr 2ndQtr 3rdQtr 4th Otr
1stOtr 2nd Qtr 3rdOtr 4thOtr 1stOtr 2nd Otr 3rdQtr 4thQtr
Carbon Tetrachloride 15 "o/LI Chloroform Chloromethane Methylene Chloride Chloride (70 "g/L) (30 un/LI • 15 "g/L) No GWQS (mg/L) Nitrate, Nitrate + Nitrite (10mo/L) 3/16/2005 NA 3.100 NA N A N A 5.2 5/25/2005 NA 2.700 NA NA NA 5.4 8/31/2005 <10 3,100 <10 <10 NA 5.2 1��g: ::� �:�gg+.:::;:��----+:::;:ca�-----+------!"'!'l---------'5��e!I 6/14/2006 <50 2,200 <50 <50 47 4.5 7/20/2006 <SO 2,140 <SO <50 51 4.7
�:�@�+-------;�:5"'1 �:��� :�:� =�:� ----':�;'1------··-__ 4-� 6/27/2007 1.5 2.600 <1.0 <1.0 45 5.1 8/15/2007 1.4 2.300 <1.0 <1.0 44 4.7 1����gg; ;� ;�ggf':'-';"'g----+:::c;c,g'------1-------'::,,�'l---------':"-;WI 6/25/2008 1.3 1,800 <1.0 <1.0 43 4.8 9/10/2008 1.4 1,600 <1.0 <1.0 35 4.16
10/15/2008 N A #N/A N A NA 40 4.01 ll-,1,--st'"'a"t,--�17��cc)8"'=1���: <2.0 _____1-.2-' �:���f':"'�"':�----+:.:-��:��------J!'Ne:Ac..._ ____ 3_5+#e,N:,,iAc,_ _____ 3 __ 7-1I 2ndQtr 6/23/2009 <1.0 1.400 <1.0 <1.0 37 3.8 3rdQtr 9/14/2009 1 1.500 <1.0 <1.0 37 4.1 4th Qtr 12/29/2009 <1.0 1.300i-:<c,_1,;.0 ____ ➔;<:..,1.,_,.0c..._ ____ -J-___ �_...:3".!7-l-______ _:4°".2'11
1stOtr 2/25/2010 <1.0 1.200 <1.0 <1.0 35 3.8 2ndOtr 6/14/2010 <1.0 1.100 <1.0 <1.0 31 3.9 3rdOtr 8/11/2010 1 1,500 <1.0 <1.0 36 3.9 4thOtr 1011512010 <1.0 1.100+.:<-;-1"'.0 ____ +<�1"".o�----+------'3�8'1-------...,..:4�I 1stQtr 2/23/2011 <1.0 1.300 <1.0 <1.0 45 3.6 2ndQtr 6/1/2011 <1.0 1.200 <1.0 <1.0 35 4.0 3rd Qtr 8/18/2011 <1.0 1.200 <1.0 <1.0 37 4.1
%�-8N-c1)--1����·""��'-!�'+:°')"':��-----+ �:��� :�:� ·�<
-�1:_go_______ . ----- -
-4;;1 ;4:_�o 2ndOtr ---6/14/2012 <1.0
_________ ----790 <1.0 _____ _ 3rdQtr 9/13/2012 <1.0 870 <1.0 <1.0 40 3.8 4thOtr 10/4/2012 <1.0 940 <1.0 <1.0 41 3.8 1stQtr 2/13/2013 <1.0 940 <1.0 <1.0 37.7 3.51 2nd Otr 6/18/2013 <1.0 953 <1.0 <1.0 39.3 4 3rdOtr 9/12/2013 <1.0 1.040 <1.0 <1.0 36.4 4.17 4thOtr 11/14/2013 <1.0 1,050 <1.0 <1.0 37.2 4.13 1stOtr 2/5/2014 ••••• 5.41 946 <1.0 <1.0 38.2 4.24 2ndOtr 5/22/2014 4.78 847 <1.0 <1.0 37.7 4.19 3rdQlr 8/27/2014 <1.0 857 1.5 <1.0 39 2.9 4thQtr 10/30/2014 <1.0 926 <1.0 <1.0 40.2 3.68 1st'atr(2) 3/18/2015 <1.0 ___ -------942 <1.0 ______ <1.0 _______ • 40.4 4.25 2ndQtr 6/11/2015 <1.0 950 <1.0 <1.0 42.1 2.62 3rd Otr 9/10/2015 <1.0 897 <1.0 <1.0 46.7 4.72 4thO1r 10/29/2015 <1.0 847 <1.0 <1.0 40.6 3.49
1st Qtr 3/22/2016 <1.0 834 <1.0 <1.0 42.4 4.43 2ndQtr 6/8/2016 <1.0 909 <1.0 <1.0 44.1 3.75 3rdOtr 8/4/2016 <1.0 1.000 �--<1.0 � � 4.21 4thQtr �/2016 <1.0 ---886 � <1.0 45.8 4.33 1st Otr 3121f.fo'f7 <r·o 986 <fO- ··•
<1.0 40.5 3.87 2nd Otr 6/21/2017 <1.0 968 <1.0 <1.0 43.3 4.15 3rdQtr 8/4/2017 <1.0 1,070 <1.0 <1.0 44.7 4.20 4thOtr 101n12011 <1.0 884 <1.0 <1.0 43.7 4.35 DWMRC split samole <7.6 890 <12 17 J 42.0 4.30 1stOtr 3/21/2018 <1.0 721 <1.0 <1.0 44.5 3.96 2nd Qtr 6/14/2018 <1.0 751 <1.0 <1.0 41.5 4.45 3rdOtr 9/6/2018 <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 1stOtr 3/20/2019 <i:o 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 3rdOtr 9/12/2019 <1.0 801 <1.0 <1.0 39.6 3.76 4th Otr 12/18/2019 <1.0 546 <1.0 <1.0 47.2 3.11 1stOtr 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 DeplicateTW4-75 <1.0 871 <1.0 <1.0 43.1 4.19 3rdQtr 9/19/2020 <1.0 971 <1.0 <1.0 41.5 3.87 4thOtr 11/11/2020 <1.0 967 <1.0 <1.0 42.8 4.40 DWMRC solitsamole <10 930 <20 <20 43 3.90 1stOtr 3/24/2021 <1.0 875 <1.0 <1.0 46.2 4.25 2nd Qtr 6/17/2021 <1.0 819 <1.0 <1.0 41.7 4.80 3rdOtr 9/23/2021 <1.0 801 <1.0 <1.0 42.8 4.58 4th Qtr 12/9/2021 <1.0 868 <1.0 <1.0 42.9 3.02 1stQtr 3/24/2022-:C1.o 776 2.1 <1.0 41.3 4.10 2nd Otr 6/22/2022 <1.0 447 <1.0 <1.0 42.5 3.90 3rdOtr 9/15/2022 <1.0 887 <1.0 <1.0 45 3.77 4th Otr 12/9/2022 <1.0 824 <1.0 <1.0 44.8 4.06 1stOtr 3/29/2023 <1.0 619 2.1 <1.0 44.9 3.85 2nd Qtr 6/21/2023 <1.0 706 <1.0 <1.0 45.7 3.89 3rdOtr 9/2712.023 <1.0 790 <1.0 <1.0 45.2 4.02 (1 l As of March 2012 t,oth nol"lh and south wild hie ponds � lon9!,r rece•Vll'li water_ (2lchloroformpumpang:,wlls TW4-1 andTW4-2started 1n 1/14115 ______ _ NA and #N/A(for11raphs) = not analyzed Shaded indicates concentrations exceeding GWOS. Bold and Italics indicates the MOL exceeded the GWOS. J "'Aw(OlM'la!ed value
TW4-8
Sampling Event
TABLE 1 (11 of 33)
Historic Summary Of Monitoring Well Analytical Results Up To The 3rd Quarter 2023
Chloroform Contamination Investigation
OUSA White Mesa Mill
Parameter
IGWQSl
Carbon Tetrachloride Chloroform Chloromethane Methylene Chloride Chloride Nitrate, Nitrate+ Nitrite
1st0tr
2nd Otr
3rd Qtr
4lhQtr
1stQtr
2ndOtr
3rd Otr
4th Qtr rSTOtr
2nd Qtr
3rd Otr
4thQtr
1stOtr
2nd Otr
3rd Qtr 4thQtr
1stQtr
2nd Qtr
3rd Qtr
4thOtr
1stOtr
2nd Otr
3rd Qtr
4thOtr
1stQtr
2nd Ctr
3rd Qtr
4th Ctr
3/16/2005
5/25/2005
8/31/2005
12/7/2005
3/9/2006
6/14/2006
7/20/2006
11/8/2006
2128/2007
6/27/2007
8/15/2007
10/10/2007
3/28/2008
6/25/2008
9/10/2008
10/15/2008
-3/4/2009
6/23/2009
9/14/2009
12117/2009 2124/2010
6/14/2010
8/18/2010
10/15/2010
2116/2011
5/25/2011
8/16/2011
11/16/2011
(1) 12/7/2011 1st0tr(� 1/18/2012
15 uo/L)
NA
NA
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.o
<1.0
<1.0
<1.0
<1.0 ·<ro
170 •oil)
10 NA
<1.0
1.1
<1.0
1.3
1.8
<1.0
<1.0 •• 2.5
NA
<1.0
<1.0
<1.0 ·;;·:o 2.5 <1.0
1.5 <1.0
3.5 <1.0
<1.0 <1.0
<1.0 <1,0
<1.0 <1,0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1_0 ___ <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
130 ug/L) 15 •• ,u
NA
NA
1.7 NA
<1.0
2.1 <1.0
1.0 <1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
2nd Ctr ---5/13/2012 <1.0 ----<TO ____ <1:0 ______ <1.0 -----
3rd Qtr 8/29/2012
4lhQtr 10/3/2012
1s1Otr 2/7/2013
2nd Otr 5/30/2013
3rd Qtr 9/5/2013
4thQtr 1117/2013
1stQtr 1/23/2014
(2) 216/2014
2ndOtr 5/2212014
3rdOtr 8/27/2014
4th Qtr 10/29/2014
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 63.8 <1.0
<1.0 100 <1.0
<1.0 122 <1.0
<1.0 107 <1.0
<1.0 191 <1.0
1stQtr(4) -3/1212015 <1.0 ---------961 <TO ______
2nd Otr 6/11/2015 <1.0 981 <1.0
3rd Qtr 9/10/2015 <1.0 747 <1.0
41hQtr 10/29/2015 <1.0 770 <1.0
1st Ctr 3/17/2016 <1.0 634 <1.0
2nd Ctr 6/8/2016 <1.0 595 <1.0
3rd Ctr 8/4/2016 <1.0 522 <1.0
4th Qtr �/27/2016 <1.0 472 <1.0
1st Ctr 3]2112011 <1.0 359 <1.0
2nd Ctr 6/21/2017 <1.0 256 <1.0
3rdOtr 8/4/2017 <1.0 223 <1.0
41hQtr 10/11/2017 <1.0 214 <1.0
TW4-75 <1.0 194
&Ditta.a--'• <1.9 230
3/21/2018 <1.0 220 <1.0
TW4-75 <1.0 171 <1.0
Qtr 6/14/2018 <1.0 155 <1.0
Qtr 9/5/2018 <1.0 137 <1.0
4th Qtr 12113/2018 <1.0 93.8 <1.0
1st Ctr 3/19/2019 <1.0 103 <1.0
2nd Qtr 6/19/2019 <1.0 96 <1.0
3rdQtr 9/12/2019 <1.0 75.4
Deplicate TW4-75 <1.0 75.6
4thQtr 12118/2019 <1.0 84 4
1st Ctr 3/18/2020 <1.0 55.0
2nd Qtr 6/1212020 <1.0 53.8
3rdOtr 9/18/2020 <1.0 39.5
4th Qtr 11/11/2020 <1.0 51.3
DeplicateTW4-70 <1.0 52.9
:sclit1amole <10 50.0
3/18/2021 <1.0 26.9
6/16/2021 <1.0 22.3
9/2212021 <1.0 17.0
TW4-70 <1.0 16.4
Qtr 1218/2021 <1.0 17.2
Qtr 3/23/2022 <1.0 15.1
dQtr 6/16/2022 <1.0 10.9
Qtr 9/14/2022 <1.0 15.3
Qtr 1218/2022 <1.0 4.4
Qtr 3/29/2023 <1.0 9.1
2ndQtr 6/21/2023 <1.0 10.9
3rd Qtr 9/14/2023 <1.0 7.4
(1) VO Cs were resampled because laboratory missed holding time.
(2) Resampled lo verify chloroform concentrahon that was collected on 1123/14
(�As.of March 2012 both north and south WIid ltfe � flO � rece1w� wale!'_ j�chloroform_e.impng_well5TW4-1 andTW4-2starled1n 1/14/15 ______ _ NA and #N/A(fot graphs)"' not analyzed
Shaded indicates concentrations exceeding GWQS.
J ,. Approximated value
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<20
<1.0
<1.0
<1.0
<1.0
<1.0 -�"f(l
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
H = Sample was analyzed beyond holding limes and may not be accureate concentratJon
1.12
4.7 J
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0 ----
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1._0 ___
<1.0
<1.0
<1.0
<1.0
<1.0
<3.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<20
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
No GWQS (mall) 110 mg/L)
NA <0,1
NA 0.2
NA <1.0
41 <1.0
39 0.3
37 <1.0
39 0.1
40 <.1
39 0.7
42 0.2
42 <1.0
43 0.5
46 0.1
45 <1.0
39 <0.05
44 <0.05
42 <0.1
44 <0.1
44 <0.1
51 <0.1
57 <0.1
42 <0.1
45 <0.1
46 0.1
52 <0.1
45 0.1
46 0.1
45 0.2
NA #NIA 45 0.3
---------44 0.2
48 0.1
47 <0.1 46.6 0.41
45.5 <0.1
47.5 0.1
46.1 <0.1
48.5 0.166
46.5 0.166
53 0.538
47 0.6
46.7 0.914
49.6 2.3
53 1.88
59.6 1.96
52 2.2
54.2 vis
58.7 2.14
56.9 ---2.-10
60.1 2.16 5"74 2�06
58.8 1.97
61.2 1.64
52.2 1.92
56.2 1.71
61 1.90
60.8 1.36
60.8 1.36
53.8 1.31
63.2 1.40
53.1 1.35
54.3 1.23
56.5 1.1
52 0.999
52.5 1.030
60.1 1.21
53.8 1.04
56.9 1.06
52.6 0.894
54.7 1.27
49.9 1.27
56 0.16H
52.8 1.06
51.5 1.12
40.8 0.665
43.1 0.59
54.9 0.738
50.8 0.80
52.8 0.64
52.5 0.718
50.8 0.654
53.4 0.658
55.3 0.597
53.5 0.720
TABLE 1 (12 of 33) Historic Summary Of Monitoring Well Analytical Results Up To The 3rd Quarter 2023 Chloroform Contamination Investigation
TW 4-9 Sampling Event Carbon Tetrachloride 15 ug/LI
OUSA White Mesa Mill
Parameter IGWQSl Chloroform Chloromethane Methylene Chloride Chloride Nitrate, Nitrate+ Nitrite 170 ug/Ll (30 un/LI 15 ua/Ll No GWQS (mg/L) (10 mail)
1st Qtr 3/1612005 NA 3.6 NA NA NA 1.3 2nd Qtr 5125/2005 NA 1.2 NA NA NA 1.3 3rd Qtr 8/31/2005 <1.0 <1.0 2.9 <1.0 NA 1.3 ���g:; 1��g: :�:g�-----1-:��:��----+<.LQc._ __ ""'2"".6,+<:c,<:�:g�----+-----...;,��e+--------_'.c�:;1;1 2nd Otr 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 �:�g�-l-:"":"':g'-------l -':�"":g:c-------1��:g :�:g :: 2ndQtr 612.7/2007 <1.0 21 <1.0 <1.0 42 1.3 3rdOtr 8/15/2007 <1.0 9.5 <1.0 <1.0 38 1.8 ,1-;����g"":�;--�1����1��������� .. :�;�:g'-----��:tg,-------+-------';"'�'+------------,2'°".11 2ndQtr 6/25/2008<1.0 1<1.0 <1 .0 35 2.3 3rd Qtr 9/1 0/2008 <1.0 <1.0 <1.0 <1.0 28 2.79 4thOtr 10/15/2008 <1.0 <1.0 <1.0 <1 .0 58 1.99 ;·st atr 31412009 <1.0 <1.o <1.0 <1.0 30 i5 2ndOtr 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 f�"'�""g"':;-----"1�ec1!.!;"�"'�""��'J..=-:�":�"--------1��":g"---+':'-':"":g'----+:°':"':g'-------+--------!"';+----------j'-'::�I
2ndQtr 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
2ndQtr 5/25/2011 <1.0 <1.0 <1.0 <1.0 38 3.4 3rd Otr 8/16/2011 <1.0 <1.0 <1.0 <1.0 21 4 4thQtr 11/16/2011 NA NA NA NA 36 2.3 (1) ........ _ 12/7/201'-'1+<�1"S.Oe------+<1.0 <1.0 <1.0'---------l"N,:,A _____ ---l-______ _,,#,:,N"'I/A1 lslellr izi 111612012 <1.0 :CTii <1.o -<Lii 26 2.3 2nd Otr ---5/31/2012 <1.0 -----<1:0 ____ <11i ______ <1.0 ---------------23 4.0 3rd Qtr 8/30/2012 <1.0 <1.0 <1.0 <1.0 22 3.9 4thOtr 10/3/2012 <1.0e___ _____ i-:<cc1c,.0 __ -J;::_<1".o"-----1<1.0 21 3.8 1stOtr 2/7/2(ffa':;;:·(o <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 3rdOtr 9/5/2013 <1.0 <1.0 <1.0 <1.0 22.7 4.03
____.232� ::�� 2nd Qtr 5/22/2014 <1.0 6.9 <1.0 <1.0 24 3.44 3rd Otr 8/14/2014 <1.0 47 <1.0 <1.0 27 2.7 4th Otr 10/29/2014 <1.0 101 <1.0 <1.0 25 4.29 1stOtr 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 3rdOtr 9/3/2015 <1.0 48 <1.0 <1.0 39.3 1.44 4thOtr 10/28/2.015 <1.0 68.4 <1.0 <1.0 29.2.1------2.89 1stOtr 3/17/2.016 <1.0 74.3 <1.0 <f.O 3f6 2.51 2nd Qtr 6/8/2.016 <1.0 76.2 <1.0 _ <1.0 35.1 __ 2.16 3rdQtr 8/3/2016 <1.0 ----76.8 <-1.-0---�1.0 33.6 2.11 4th Otr 10/2.6/2.016 <1.0 76.0 <1.0 <1.0 --37.4 2.24 1stOtr 3/17/2017 <1.0 113 <1.0 <1.0 34.5 2_·,a 2nd Otr 6/21/2.017 <1.0 113 <1.0 <1.0 35.9 1.92 3rdOtr 8/3/2.017<1.0 118 <1.0 <1.0 37 1.90 4th Qtr 10/11/2.017 <1.0 132 <1.0 <1.0 32 2.18 fJWM��P.!it&amDle <0.98 120 <1.5 1.6J 35 ______ �2.20 1stQtr 3/21/2.018 <1.0 159 -�:co <1.0 38.3 2nd Qtr 6/4/2018 <1.0 134 <1.0 <1.0 35.7 1.85 Deplicale TW4-75 <1.0 132 <1.0 <1.0 35.2 1 .9 1 3rdOtr 9/5/2.018 <1.0 94.2 <1.0 <1.0 43.4 1.04 DeplicateTW4-75 <1.0 92.4 <1.0 <1.0 42.7 1.11 4th Qtr 12/13/2016 <1.0 109 <1.0 <1.0 36.3 1.23 1stOtr 3/19/2019 <1.0 _ 86.4 <1.0 <1.0 36.9 1.09 2nd Otr 6/19/2019 <1.0 68.1 <1.0 <1.0 38.3 0.785 3rd Qtr 9/11/2019 <1.0 66.0 <1.0 <1.0 35.2 0.904 4thOtr 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 2ndOtr 6/12/2020 <1.0 55.1 <1.0 <1.0 39.5 0.990 Oepl!cateTW4-70 <1.0 56.4 <1.0 <1.0 39.6 1.010 3rd Qtr 9/18/2020 <1.0 45.0 <l.O <1.0 36.7 0.867 4thQtr 11 /11/2020 <1.0 47.1 <1.0 <1.0 37.2 1.11 OWMRC split aample <10 48.0 <20 <20 38 0.97 �:.��� Dupsamp����.;�i,..,_:���'------->-----4�3 4�0�; �:� OeplicateTW4-70 <1.0 38.2 <1.0 <1.0 38.7 1.07 2ndQtr 6/16/2.021 <1.0 ,_ 102 <1.0 <1.0 37.4 2.0 3rd Otr 9/22/2021 <1.0 30.0 <1.0 <1.0 30.8 0.700 4th Qtr 12/8/2021 <1.0 25.4 <1.0 <1.0 36.9 0.798 1st Qtr 3/23/2022 <1.0 16.5 <1.0 <1.0 34.6 0.80 2ndQtr 6/22/2022 <1.0 9.8 <1.0 <1.0 41.7 0.62 3rdOtr 9114/2022 <1.0 10.8 <1.0 <1.0 32.4 0.673 DeplicateTW4-70 4th Qtr Deolicate TW4-70 1stOtr Deplicate TW4-70 2nd Otr DeplicateTW4-70 3rd Ctr
<1.0
12/8/2022 <1.0
<1.0 3/29/2023 < 1.0 <1.0 6/21/2023 <1.0
<1.0 9114/2023 < 1.0 (1) voes wei-e reumpled because laboratory missed holding time.
8.7 <1.0 <1.0 32.4 0.660 6.7 <1.0 <1.0 33.2 0.676 6.0 <1.0 <1.0 56.5 0.660 6.2 <1.0 <1.0 37.1 0.765 5.6 <1.0 <1.0 36.4 0.743 5.0 <1.0 <1.0 38.0 0.742 4.8 <1.0 <1.0 38.0 0.733 6.2 <1.0 <1.0 36.2 0.690
j2) Aa of March 2012 both north and south wild life� � � receiVlni watef. NA and IN/A(fOf waphs) " not anatvzed Shaded indicates concentranons exceedlnQ GWOS. J ,. Approximate value
TABLE 1 (13 of 33)
Historic Summary Of Monitoring Well Analytical Results Up To The 3rd Quarter 2023
Chloroform Contamination Investigation
OUSA White Mesa Mill
TW4-10 Parameter
Sampling Event IGWCSI
Carbon Tetrachloride Chloroform Chloromethane Methylene Chloride
1stQtr J/16/2005
2ndQtr 5/25/2005
3rd Qtr 8/31/2005
4th Ctr 12/7/2005
1stQtr 319/2006
2nd0tr 6/14/2006
3rd Qtr 7/20/2006
4th0tr 11/8/2006
1st0tr 2/28/2007
2nd Otr 6/27/2007
3rdQtr 8/15/2007
4th Ctr 10/10/2007
1st0tr 3/28/2008
2ndQtr 6/25/2008 3rd Qtr 9/10/2008
4thQtr 10/15/2008
11/18/2008
1stQtr 3/11/2009
2nd Qtr 6/23/2009
3rdQtr 9/14/2009
4thQtr 12/22/2009
1st0tr 3/3/2010
2ndQtr 6/14/2010
3rd Otr 8/12/2010
4thQtr 10/15/2010
1stQtr 2/23/2011
2nd0tr 6/14/2011
3rdQtr 8/17/2011
4th0tr 11/16/2011 1st Otr (1) --1/19i2012
I5ug/L)
NA
NA
<2.5
<2.5
<5.0
<5.0
<5.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
NA
<2.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
(70 un/L) (30 ug/L) 15 ug/L)
140 NA NA
62 NA NA
110 6.2 <2.5
300 <2.5 <2.5
190 <5.0 <5.0
300 <5.0 <5.0
504 <5.0 <5.0
452 1.6 <1.0
500 <1.0 <1.0
350 <1.0 <1.0
660 <1.0 <1.0
470 <1.0 <1.0
620 <1.0 <1.0
720 <1.0 <1.0
660 <1.0 <1.0
#NIA NA NA
1.200 <2.0 <2.0
1.100 <1.0 <1.0
1.200 <1.0 <1,0
910 <1.0 <1.0
JOO <1.0 <1.0
460 <1.0 <1.0
220 <1.0 <1.0
100 <1.0 <1.0
1.100 <1.0 <1.0
620 <1.0 <1.0
280 <1.0 <1.0
180 <1.0 <1.0
110 <1.0 <1.0
76 <1.0 <1.0
2nd Qtr ---6/14/2012 <1.0 -----<1.0------<1.0 ------
3rd0tr 9/12/2012 <1.0 130 <1.0
4th0tr 10/3/2012 <1.0 140 <1.0
1st0tr 2/13/2013 <1.0 154 <1.0
2nd Qtr 6/13/2013 <1.0 486 <1.0
3rdQtr 9/12/2013 <1.0 1.126 <1.0
4th Ctr 11/14/2013 <1.0 1.380 <1.0
1st0tr 1/29/2014 5.16 1.260 <1.0
2nd Qtr 5/23/2014 <1.0 1.110 <1.0
3rd0tr 8/27/2014 <1.0 1.060
4th Ctr 10/30/2014 <1.0 1.220 <1.0
1stQtr 3/18/2015 <1.0 1.210 <1.0
2nd Qtr 6/11/2015 <1.0 1.240 <1.0
3rdQtr 9/10/2015 <1.0 1.280 <1.0
4th Ctr 10/29/2015 <1.0 1.350 <1.0
1statr· ·-----3/22/2016 <1.0 1.430 <1.0
2nd0tr � 1.510 � 3rdQtr <1.0 1.500
4th Otr �6/2016 <1.0 ---1.290
1stQtr 3/21/2017 <1.0 1.260
2nd Qtr 6/21/2017 <1.0 1.140
3rdQtr 8/4/2017 <1.0 1.320
4th Otr 10/11/2017 <1.0 1.150
DWMRC&olitsamn!A <9.5 1.100
1stQtr 3/21/2018 <1.0 1.240
2nd 6/14/2018 <1.0 914
3rdQtr 9/6/2018 <1.0 911
4th Otr 12/13/2018 <1.0 1.070
1st0tr 3/20/2019 <1.0 869
2nd Qtr 6/19/2019 <1.0 799
3rd0tr 9/12/2019 <1.0 734
4th Qtr 12/18/2019 <1.0 768
1st0tr 3/18/2020 <1.0 798
2nd Otr 6/11/2020 <1.0 928
3rd Ctr 9/19/2020 <1.0 854
4th Qtr 11/11/2020 <1.0 903
1st0tr 3/18/2021 <1.0 718
2nd Otr 6/17/2021 <1.0 609
3rd Ctr 9/23/2021 <1.0 545
4th Ctr 1219/2021 <1.0 675
1stQtr 3/24/2022 <1.0 471
Deplicate TW4-75 <1.0 456
2nd Qtr 6/22/2022 <1.0 342
3rd Ctr 9/15/2022 <1.0 563
4th Qtr 12/9/2022 <1.0 499
1st0tr J/29/2023 <1.0 361
2nd Qtr 6/21/2023 <l.O 322
3rdQtr 9/27/2023 <1.0 286
(1) As of March 2012 both north and south WIid lrfe eond5 n0 k>n9!" �ecervtng_watef _ NA and #N/A(for graphs)• not analyzed
Shaded indicates concentration& exceeding GWOS.
J = ApproxJmate value
<1.0
� -;:i_o
<1.0
<1.0
<1.0
<15
<1.0 <1.0
<1.0
<1.0 <1.0
<1.0 <1.0
<1.0
<1.0 <1.0
<1.0 <1.0
<1.0
<1.0 <1.0
<1.0
<1.0
<1.0 <1.0
<1.0 <1.0 <1.0
<1.0
<1.0
<1.0
<1.0
<1.0 <1.0
<1.0
<1.0 1.5 <1.0
<1.0
<1.0 <1.0
<1.0 <1.0
<1.0
<1.0 <1.0
<1.0 ___ <1.0
<1.0
<1.0 <1.0
16J <1.0
<1.0
<1.0
<1.0
<1.0 <1.0
<1.0
<1.0 <1.0
<1.0
<1.0
<1.0
<1.0 <1.0
<1.0 <1.0
1 <1.0
1 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0
<1.0
Chloride
No GWCS (ma/LI
NA
NA
NA
52
50
54
61
58
2
54
59
59
55
58
51
61
NA
64
62
51
51
48
42
38
52
32
42
41
45
40 ----46
44
45
49.1
51.5
67.9
70.9
73
77.J
74
75.2
78.6
75
89.5
79.9
84'."i
89.5
---85-.3
�4
74:S
73.1
77
70
76
72.7
64.5
75.5
63.5
59.3
58.7
55.8
62
53:5
60.1
53.9
58.6
58.1
48.7
50.6
51.9
4s:o
44.8
46.0
52.0
43.4
48.6
46.9
44.8
Nitrate, Nitrate+ Nitrrte
(10 mg/L)
1.6
0.8
1.1
3.3
2.4
3.5
6.8
5.7
7.3
5.1
7.3
6.7
7.3
9.9
9.23
10 5
#N/A
11.6
9.8
8.1
3.8
5.0
1.6
0.8 11 0
9.0
J.J
1.9
1.1
0.9
0.8
1.0
1.6
1.2
5.6
13 0
16 0
16.8
13.9
9.8
13 2
15 0
11 4
14.0
13.5
17 J
14 9
14 9
14 8
13.0
13 0
13 4
12 9
13 0
11.1
11 2
10 1
10.6
9.34
8.86
7.79
6.89
7.83
8.13
7.34
8.69
7.20
7.75
6.35
5.47
5.i
4.9
4.6
5.57
4.76
4.2
J.8
3.18
TABLE 1 (14 of 33)
Historic Summary Of Monitoring Well Analytical Results Up To The 3rd Quarter 2023
Chloroform Contamination Investigation
TW4-11(chlafofoon pumpmg �
11aned1114115)
Sampling Event
1st0tr 3/16/2005
2nd0tr 5/25/2005
3rd Ctr 8/31/2005
4thQtr 12/7/2005
1st0tr 3/9/2006
2nd Otr 6/14/2006
3rd Qtr 7/20/2006
4th Qtr 11/8/2006
1st Ctr 2/28/2007
2nd Qtr 6/27/2007
3rd Ctr 8/15/2007
4th Qtr 10/10/2007
1st Ctr 3/28/2008
2nd Qtr 6/25/2008
3rd0tr 9/10/2008
4th Qtr 10/15/2008
11/18/2008
1st Ctr 3/11/2009
2nd Qtr 6/23/2009
3rd0tr 9/14/2009
4th Qtr 12/22/2009
1st0tr 3/3/2010
2nd Otr 6/14/2010
3rdQtr 8/12/2010
4th Qtr 10/15/2010
1stQtr 2/23/2011
2nd Qtr 6/1/2011
3rdQtr 8/17/2011
4th Qtr 11/16/2011 rsra-t, 111 112412012
2nd at, ---6/13/2012
3rd0tr 9/13/2012
4thQtr 10/3/2012
1st0tr 2/13/2013
2nd Qtr 6/18/2013
3rd0tr 9/12/2013
4th Qtr 11/13/2013
1stQtr 2/5/2014
2nd Qtr 5/23/2014
3rd0tr 8/27/2014
4th Otr 10/29/2014
1st Qtr(2) 3/9/2015
2nd Qtr 6/11/2015
3rdQtr 8/31/2015
4th Qtr 10/29/2015
1st0tr 3/9/2016
2nd Qtr 5/23/2016
3rdQtr �/2016
4th Qt1 -,W,212016
1st0tr 3/8/2017
2nd Otr 6/13/2017
3rd0tr 7/26/2017
� 10/11/2017
DWMRC·--�-"'-
1stQtr 3/12/2018
2nd Qtr 6/8/2018
3rd0tr 8/22/2018
£1}_9tr 11/28/2018
1st0tr 3/8/2019
2nd Qtr 6/5/2019
3rd Otr 9/4/2019
4th0tr 12/18/2019
1stQtr 2/19/2020
2nd Otr 5/11/2020
3rdQtr 9/4/2020 4th0tr 10/28/2020
1st Ctr 2/23/2021
2nd Qtr 6/9/2021
3rd Otr 8/24/2021
4thQtr 12/1/2021
1st Ctr 3/9/2022
2nd0tr 6/8/2022
3rd Qtr 9/15/2022
4thQtr 11/30/2022
1stQtr 317/2023
2nd0tr 6/13/2023
3rd Otr 819/2023
Carbon Tetrachloride
(5 µail)
NA
NA
<10
<100
<SO
<50
<SO
1.7
1.3
1.6
1.7
1.6
<1.0
<1.0
<1.0
NA
<2.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0 <1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0 ----
<1.0
<1.0
3.23
<1.0
<1.0
<1.0 5.19
<1.0
<1.0
<1.0
1.24
<1.0
<1.0
<.1..0 1.2
2.19
<1.0
�to
1.71
1.83
1.81
1.48
<38
1.82
1.34 1.47
1.33
1.48
1.52
1.47
<1.0
<1.0 1.37 1.47
<1.0
<1,0
<1.0
<1.0
<1.0
<1.0 1.0
<1.0
<1.0 <1.0 1.0
<1.0
Chloroform
170 ua/LI 4.400
3,590
4,400
4,400
4,400
4,300
4,080
3,660
3,600
3.800
4,500
4,400
340
640
900
#N/A 1,000
1,000
980 1,000
860
820
820 800
720
1,000
930
820
1500
610
----660
740
730
867
788
865
874
785
751
719 803
----2�50
2,710
1,120
2,730
2.660
3,340 3,200
3,200
3,310
3,370
3,290
2,880
2,900
3,090 2,800
3,050
2,930
2,820
2,970 2,790
3,250
2,990
2,810
3,070
2,670
2.750
3,320
2,600
2,850
2,780
2,550
3,020
2.900
2.430 2,510 2630
(1 AaofMarch2012bothnorthand&OUthwildbfe ,no -�------------------pond-long,< receMng water
(�Chloroform_puJ!l�weUstarted 1/14115 _______ _ NA• not analvzed
Bold and italics indicates the MDL exceeded the GWQS.
Bold and italics indicates the MDL exceeded the GWQS.
J ,. Approximated value
OUSA White Mesa Mill
Chloromethane
(30 ug/L)
NA
NA
<10
<100
<50
<50
<50
2.7
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
NA
<2.0
<1.0 <1.0
<1.0
<1.0
<1.0
<1.0 <1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<l:O ______
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0 <1.0
Parameter
IGWQSI
Methylene Chloride
15 ua/LI NA
NA
<10
<100
<SO
<50
<50
1.3
1.6
<1.0
<1.0
1.2
<1.0
<1.0
<1.0
NA
<2.0 -�·ro
<1.0
<1.0
<1.0
<1.0 <1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0 -----
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0 :::ro
<1.0
1.2 <1.0
<1.0 <1.0
<l:O ______ <1.0 -----
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0 � <1.0 <fa <1.0
<1.0 <1.o
<1,0 <1.0
<1.0 <1.0
<1.0 <1.0
<60 140 J
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 -�·;·-.o
1.4 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
3.86 <1.0
<1.0 <1.0
<1.0 <1,0
<1.0 <1.0
<1.0 <1.0
<1.0 ·�"Lb 2.7 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0 2.9 <1.0
<1.0 <1.0
Chloride
No GWQS (ma/LI
NA
NA
NA
58
56
56
55
55
54
53
53
53
63
46 42
47
NA 49 44 49
46
42
40
43 49
46
49
48
46
43 ---52
49
50
47.3
49.3
46.6
46.7
48.5
51.6
48 56.4
49.8
62.2 73.1
55.3
55.5
56.4
55.3
----57.2
49.8
51.4
51
49.7
52
54
52.4
53.3
45.4
46.8
45.3
48.8
49.0
51.9
48.6
46.3
43.3
49.5
37.7
40.2
48.4
41.5 44.5
42.4 36.6
39.2 40.9 ,r'
Nitrate, Nitrate + Nitrite
110mn/L)
8.7
10 3
9.4
9.4
9.2
10.0
10.0
10.0
10.1
10.6
10 2
9.8
7.7
7.3
7.9
9.5
#N/A
7.3
6.8
7.0
6.6
6.8
6.9 6.7 6.4
6.5
7.3
7.1
7.1
6.8
6.7
3.0
7.0
6.8
7.4
7.8
8.01
8.47 6.92
5.4 7.33
8.72
8.48 9.61
7.5
7.13
7.81
8.83
8.92
8.12
7.92
7,78
7.7 R' ;1 7.1 6.8
7
··� 8.
7.1
7.1
7.1 7.!
7. 7.
7.
8. 5.
7.•
7. 5
6 7
5
6 <
TABLE 1 (15 of 33)
Historic Summary Of Monitoring Well Analytical Results Up To The 3rd Quarter 2023
Chlorofonn Contamination Investigation
TW4-12
Sampling Event
1stOtr 3/16/2005
2ndQtr 5/25/2005
3rd Qtr 8/31/2005
4thQtr 12/7/2005
1st0tr 3/9/2006
2ndQtr 6/14/2006
3rd Qtr 7/20/2006
4th0tr 11/8/2006 ·:,-stOtr 2/28/2007
2nd Qtr 6/27/2007
JrdOtr 8/15/2007
4thQtr 10/10/2007
1st0tr 3/28/2008
2ndOtr 6/25/2008
3rd Otr 9/10/2008
4thQtr 10/15/2008 1statr-3/11/2009
2nd Qtr 6/23/2009
3rd Ctr 9/14/2009
4th Qtr 12/16/2009
1st Ctr 2/23/2010
2nd Qtr 6/14/2010
3rd Ctr 8/10/2010
4th Qtr 10/15/2010
1st Ctr 2/15/2011
2nd Ctr 5/25/2011
3rdQtr 8/16/2011
4th Qtr 11/15/2011 1s1Qtr (1) 1/17/2012
2nd Otr ---5/31/2012
3rd Ctr 8/29/2012
4thQtr 10/3/2012
1st Ctr 2/13/2013
2nd Ctr 5/29/2013
3rd Ctr 8/29/2013
4th Qtr 11/6/2013
1st Ctr 1/22/2014
2nd Otr 5/21/2014
3rd0tr 8/27/2014
4thQtr 10/23/2014
1st Ctr 3/11/2015
2nd Otr 6/10/2015
3rdQtr 9/2/2015
4th Otr 10/21/2015
DeDlicateTW4-65
:iStatr 3/15/2016
2nd Qtr 5/25/2016
l:leQl,c:alelW4-4 5/25/2016
3rd0tr 7/27/2016
4th Otr 10/12/2016
1st0tr 3/14/2017
2nd Qtr 6/14/2017
Carbon Tetrachloride
f5 uo/LI
NA
NA <1.0
<1.0
<1.0 <1.0
<1.0
<1.0 <1.0
<1.0
<1.0
<1.0
<1.0 <1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
-<TO
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
OUSA White Mesa Mill
Parameter fGWQSI
Chlorofonn Chloromethane Methylene Chloride 170 "g/L) (30 "g/L) (5 "gill
<1.0 NA NA
<1.0 NA NA
<1.0 5.8 <1.0
<1.0 1.0 <1.0
<1.0 2.6 <1.0
<1.0 1.4 <1.0
<1.0 1.4 <1.0
<1.0 <1.0 <1.0 <·ro <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1,0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.g
<1.0 <1.0 <1.0
<1.0 ____ <l.O ______ <1.0________
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <f'O <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <"1�0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
1.25 <1.0 <1.0
3rdQtr 8/2/2017 <1.0 1.2 <1.0 <1.0
DeplicateTW4-70 <1.0 1.19
4thQtr 10/10/2017 <1.0 <1.0
n-aicateTW4-70 <1.0 <1.0
1st Ctr 3/14/2018 <1.0 <1.0
2nd Otr 6/12/2018 <1.0 <1.0
3rd Otr 8/29/2018 <1.0 <1.0
4lhQtr 11/30/2018 <1.0 <1.0
1st Ctr 3/16/2019 <1.0 <1.0
2nd Ctr 6/13/2019 <1.0 <1.0
3rd Otr 9/11/2019 <1.0 <1.0
4thQtr 12/14/2019 <1.0 <1.0
1st Ctr 3/17/2020 <·1.0 <1.0
2nd Ctr 6/11/2020 <1.0 <1.0
3rdQtr 9/17/2020 <1.0 <1.0
4thQtr 11/4/2020 <1.0 <1.0
1st0tr 3/17/2021 <1.0 <1.0
2nd Otr 6/15/2021 <1.0 <1.0
3rd Qtr 9/15/2021 <1.0 <1.0
4th Ctr 12/7/2021 <1.0 <1.0
1stQtr 3/15/2022 <1.0 <1.0
2nd Ctr 6/15/2022 <1.0 <1.0
3rd0tr 9/13/2022 <1.0 <1.0
4th Qtr 12/7/2022 <1.0 <1.0
�teTW� <1.0 <1.0
1st Ctr 3/22/2023 <1.0 <1.0
2nd Otr 6/15/2023 <1.0 <1.0
3rd Ctr 9/13/2023 <1.0 <1.0
Deolicate TW4-65 <1.0 <1.0
(!!As of March 2012 bol:h north and south wild life ponds �lonQ!r ��water_ NA = not analyzed
Shaded indicates concentrations exceeding GWOS.
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.o
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0 �TO <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<i.O <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
Chloride
No GWQS tmo/LI
NA
NA
NA
19
19
16
16 16
16
18
29
16
16
19 18
22
23
22
22
23
22
29
35
31
31
32 31
30
28 ---------34
39
39
36.7
38.6
41.7 41.4
41.6
40.2 47
50.2
50.6
56
60.2 51
51.3
56.2
66.4
67 67.5
72.6
62.6
67.2
65.3
67
56.2
61.4
59.5
53.6
59.9
56.1
50.8
55.3
52.6
58.0
53.0
51.7
50.3
48.0
52.0
51.8
36.1
49.8
25.8
53.3
57.9
49.2
50.9
35:9
43.6
50.3 52.3
Nitrate, Nitrate+ Nitrite
f10mo/L )
1.4
1.6
1.5
1.4
1.3
1.4
1.4
1.4 1:s
1.5
1.4
1.4
1.6
2.7
2.7 2.5
2.4
3.8
5.1
3.6
4.0
11 0
9.0
8.0
6.5
7.0
6.8
8.0
7.7
10.0
130 13.0
12 6
14 2
17 4
16.4
18.4
17 0
13 0
16 1 19 2
18.8
16.4 18.0 18.0
34 8
30 7 113 0
37 7
25.8 25 9
29 9
25 1 26 7
26 9 26 8
19.8
18 4 13 6
10 4
10 1 8.31
8.88
8.04
6.39
4.95
2.34
5.91
3.10
2.39
1.95
1.46
8.4
16 0 13 8
4.68
7.02
2.84
4.7
4.02
4.66
212812007
TABLE 1 (17 of 33) Historic Summary Of Monitoring Well Analytical Results Up To The 3rd Quarter 2023 Chloroform Contamination Investigation
TW4-14 Sampling Event
1st Ctr 3/16/2005 2nd Qtr 5/25/2005 3rd Otr 8/31/2005 4th Ctr 12/7/2005 1stQtr 3/9/20062nd Ctr 6/14/2006 3rd Ctr 7/20/2006 4th Qtr 11/8/2006 1st Ctr 2/28/20072nd Qtr 6/27/2007 3rd Ctr 8/15/20074th Qtr 10/10/2007 1sIOtr 3/28/2008 2nd Qtr 6/25/20083rd Ctr 9/10/2008 4th Ctr 10/15/2008 � 3/4/20092nd Otr 6/23/20093rd Qlr 9/14/2009 4th Qtr 12116/2009 1st Ctr 3/23/2010 2ndOtr 6/14/2010 3rd Otr 8/10/20104th Qtr 10/15/2010 1stQtr 2115/20112nd Otr 6/24/2011 3rd Qtr 8/16/2011 4thOtr 11/15/2011 1sfllfrll) 1/17/2012 2nd Qtr ---6/14/2012 3rd Qtr 8/29/2012 4th Ctr 10/3/2012 1st Cir 2/7/2013 2nd Qtr 5/29/20133rd Qtr 8/29/2013 4th Ctr 11/6/20131st Ctr 1/22/2014 2ndOtr 5/21/2014 3rd Otr 8/13/2014 �Qtr 10/23/20141st Ctr 3/12/2015 2nd Ctr 6/10/2015 3rd Cir 9/3/2015 4thQtr 10/23/2015 1st Ctr 3/16120°f6 2nd Otr 5/26/2016 3rd Qtr 8/3/2016 4thQtr 10/20/20161st Ctr 3/15/2017 2nd Ctr 6/15/20173rd Ctr 8/2/2017 4thOtr 10/10/20171st Ctr 3/15/2018 2nd Ctr 6/13/20183rd Otr 8/30/2018 4thQtr 12112/20181st Ctr 3/16/2019 2nd Ctr 6/13/2019 3rd Ctr 9/11/2019 4thOtr 12114/2019 1stQtr 3/17/2020 2nd Qtr 6/11/20203rd Otr 9/18/2020 4th Ctr 11/4/20201st Ctr 3/18/2021 2ndQtr 6/16/2021 3rd Ctr 9/15/2021 4thQtr 1218/2021 1stOtr 3/16/2022 2ndQtr 6/16/20223rd Otr 9/14/2022 4th Ctr 1218/20221st Ctr 3/23/2023 2ndOtr 6/15/20233rd Ctr 9/13/2023
Carbon Tetrachloride (5 uo/Ll NS NS NS NSNS NSNS <1.0 <1.0 <1.0<1.0 <1.0 <1.0 <1.0 <1.0 <1.0<1.0 <1,0 <1.0 <1.0 <1.0 <1.0<1.0 <1.0·�1.0 <1.0 <1,0 <1.0<1.0 <1.0 -----<1.0 <1.0 <1.0 <1.0<1.0 <1.0<1.0 <1.0<1.0 <1.0<1.0 <1,0<1.0 <1.0 �·ro<1.0 <1.0 <1.0 <1.0 <1.0<1.0 <1.0 <1.0 <1.0<1.0 <1.0 <1.0 <1.0<1.0 <1.0<1.0 <1.0<1.0 <1.0 <1.0 <1.0<1.0 <1.0<1.0 <1.0<1.0 <1.0<1.0 <1.0<1.0
DUSA White Mesa Mill
Parameter IGWQSI Chloroform Chloromethane Methylene Chloride (70 ua/LI 130 uo/LI (5 un/LI NS NS NS NS NS NS NS NS NS NS NS NSNS NS NS NS NS NSNS NS NS NS <1.0 <1.0 <1.0 <1.0 -� .. 1·:o<1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0<1.0 <1.0 <1.0 <1.0 <1.0 <1.0<1.0 <1.0 <1.0 <1.0 <1.0 <1.0<1.0 <1.0 <1.0 <1.0 <1.0 <1.0<1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1,0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <TO ____ <1:0 ______ <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0<1.0 <1.0 <1.0 <1.0 <1.0 <1.0<1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 1.7 <1.0 <f0 1.82 <1.0 <1.0 <1.0 <1.0 <1.0 1.46 <1.0 <1.0 4.49 <1,0 2.18 6.15 <1.0 3.18 5 <1.0 1.8 7.02 <1.0 1.59 6.45 <1.0 2.18 6.85 <1.0 <1.0 6.14 <1.0 <1.0 6.13 <1.0 <1.0 5.8 <1.0 2.18 5.12 <1.0 <1.0 4.76 <1.0 <1.0 4.41 <1.0 <1.04.08 <1.0 <1.0 4.18 <1.0 <1.0 6.08 <1.0 <1.0 3.83 <1.0 <1.0 2.98 <1.0 <1.0 2.87 <1.0 <1.02.41 <1.0 <1.0 2.69 <1.0 <1.0 1.77 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0<1.0 <1.0 <1.0 1.0 <1.0 <1.0 1.1 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0
(1) As of March 2012 l>oth north and &OUth wild hfe M er recelVI water
____________________ !!"""' long�-� ---NS,. not sampled
Shaded 1ndtcates concentratoos exceeding GWOS.
Chloride No GWQS (mn/L) NS NS NSNS NSNS NS 37 38 38 36 385f35 34 40 35 36 38 34 33 49 35 29 25 24 33 15 20 ---------35 37 37 35.2 38.637.6 36.535.5 32.538 38.9 40.1 41.8 42.4 40.6 42.4 43.6 42.4 45.6 45.4 46.9 46.4 42.5 51.5 46.9 54.1 48.7 48.748.3 45.449.4 48.4 47.6 45.1 49.748.2 49.5 34.1 49.0 42.0 48.4 42.2 43.5 47.6 50.044.0
Nitrate, Nitrate+ Nitrite (10mn/L) NS NS NSNS NSNS NS 2.4 :23 1.4 1.1 0.8 0.4 1.6 1.380.761.6 1.4 1.5 1.4 2.5 2.9 2.8 2.9 1.8 1.4 2.6 1.7 1.9 3.3 3.9 3.9 4.6 4.4 4.514.81 5.924.87 4.1 5.22 5.223.55 2.772.45 2·94 2.45 2.88 2.864.36 5.124.84 4.73 5.67 6.36 5.34 5.85 6.165.86 4.774.76 6.176.57 5.57 5.81 5.567.02 5.565.70 5.9 5.30 4.786.20 5.58 6.12 6.22
TW4-16
Sampling Event
TABLE 1 (18 of 33) Historic Summary Of Monitoring Well Analytical Results Up To The 3rd Quarter 2023
Chloroform Contamination Investigation
OUSA White Mesa Mill
Parameter
IGWQSI
Carbon Tetrachloride Chloroform Chloromethane Methylene Chloride Chloride Nitrate, Nitrate+ Nitrite
(5 µg/L) (70 ug/L) (30 µg/L) 15 up/L) No GWQS (mg/l) (10mg/L)
1stQtr 2nd Qtr
3rd Qtr
th Qtr
stOtr
dQtr
Qtr
Otr
Qtr
d Qtr
Otr
Qtr
stOtr
2nd Qtr
3rd Otr
th Qtr
stQtr
2nd Qtr
3rd Qtr thQtr
stOtr 2nd Qtr 3rd Qtr
th Qtr stQtr
2nd Otr
3rdOtr
4th Qtr
3/16/2005
5/25/2005 8/31/2005
12/7/2005
3/9/2006
6/14/2006
7/20/2006 11/8/2006
2/28/2007
6/27/2007 8/15/2007
10/10/2007 3/28/2008
6/25/2008
9/10/2008
10/15/2008 3/4/2009
6/23/2009 9/14/2009
12/17/2009 3/24/2010
6/14/2010 8/24/2010
10/15/2010
2/22/2011 5/26/2011
8/17/2011 11/16/2011
11) 12/7/2011
NA 240 NA
NA 212 NA
<1.0 85 3.2
<1.0 14 2.6
<1.0 39 1.1
<1.0 13 2.4
<1.0 5.2 <1.0
<1.0 13.6 <1.0
<1.0 8.7 <1.0
<1.0 2.6 <1.0
<1.0 7.1 <1.0
<1.0 1.4 <1.0
<1.0 11 <1.0
<1.0 <1.0 <1.0
<1.0 10 <1.0
<1.0 3.9 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<l.O <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 2.1 <1.0
<1.0 4.3 <1.0
<1.0 3 <1.0
<1.0 15 <1.0
<1.0 16 <1.0
<1.0 9.2 <1.0
NA NA NA
<1.0 <1.0 <1.0
<1.0 <i·o <1.0
Qtr 5/26/2012 Edo,i,(31 __ 111812012
<1.0 ----<TO ____ <1:0 ______
Qtr 8/30/2012 Otr 10/3/2012 1S Qtr 2/7/2013
2nd Otr 5/30/2013
3rdOtr 9/5/2013 th Qtr 11/7/2013 -st Ctr 1/29/2014
2nd Qtr 5/22/2014
3rdOtrl2) 8/14/2014
3rdOtr 9/24/2014
th Qtr 10/29/2014
stQtr 3/12/2015 2nd Otr 6/11/2015
3rdOtr 9/3/2015
4th Qtr t0/28/2015
1st Ctr 3/17/2016
2nd Qtr 5/26/2016
3rdQtr 8/3/2016
4thOtr 10/26/2016
1stQtr 3/16/2017
2nd Qtr 6/20/2017
3rdQtr 8/3/2017
4thQtr 10/11/2017
-��-�_t_!!e!,e 3/20/2018
TW4-75
Qtr 6/14/2018
Qtr 8/30/2018
Qtr 12/12/2018
U.tr 3/19/2019
Qtr 6/19/2019
Qtr 9/12/2019
Qtr 12/14/2019
TW4-75 3/18/2020
6/12/2020 9/19/2020
11/11/2020
TW4-75
samole
Otr 3/24/2021
Qtr 6/17/2021
Qtr 9/23/2021
4th Qtr 12/8/2021
1stQtr 312Ji2022
2nd Qtr 6/22/2022
3rdQtr 9/15/2022
4th Otr 12/9/2022
1stQtr 3/29/2023
Duplicate TW4-75
2nd Qtr 6/21/2023
3rd Ctr 9/27/2023
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0
<1.0 <1.0
<1.0
<1.0 <1.0
<1.0
<1.0
<1.0 <1.0
<1.0
<1.0 <1.0
<1.0 <1.0
<1.0
<0.95
<1.0
<1.0 -<1.0
<1.0
<1.0
-<·1·.-0 <1.0
<1.0
<1.0
<1.0
<1.0
<1.0 <1.0 <1.0
<1.0
<10
<1.0
<1.0 <1.0
<1.0
<1.0 <1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
(1) voes were resampled because laboratory m1Ssed holding time.
(21 voes were resampled
<1.0
<1.0
<1.0
<1.0
<1.0 13.4 <1.0
6.93 <1.0
14.6 <1.0
229 <1.0
371 <1.0
387 <1.0 153 <1.0
65.3 <1.0
82 <1.0
112 <1.0
45.9 <1.0 93.4 <1.0
49 <1.0 92.9 <1.0
19.1 <1.0
64.3 <1.0 143 <1.0
98 <1.0 92 <1.5 170 :::1·.o
171 <1.0
54.5 <1.0
54.5 <1.0
52.0 <1.0
60.6 <1.0
76.2 <1.0
99.8 <1.0
94.3 <1.0
91.0 <1.0
113 <1.0 141 <1.0
220 <1.0
270 <1.0
277 <1.0 290 <20 248 <1.0
247 <1.0 202 <1.0
189 <1.0
150 <1.0 120 <1.0
138 <1.0
152 <1.0
179 <1.0
178 <1.0
227 <1.0 182 <1.0
(3) As of March 2012 both north and south wild life ponds no lonuer receiving water.
NA= not analyzed-------
Shaded indicates concentrations e)(ceedinR GWQS.
J ::: Appf0)(Imate valve
H = Sample was analyzed bevond holdiOA times and mav not be accureate concentration.
NA NA
<1.0
<1.0
<1.0 <1.0 <1.0
<1.0 <1.0
<1.0
<1.0
<1.0 <1.0
<1.0 NA
<1.0 <1.0
<1.0
<1.0
<1.0
<1.0
<1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0
<1.0
<1.0 <1.0
<1.0 <1.0 <1.0 ·:.:(Q <1.0
<1.0 <1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0 <1.0
<1.0 <1.0 <20
<1.0
<1.0 <1.0
<1.0
<1.0 <1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
NA <0.1
NA <0.1
43 NA <0.1
5.9 64 1.4
21 60 3
8.9 55 1.9
2.7 60 2.7
9.2 62 5.6
6.6 79 12.3
1.8 75 9.9
5.1 65 5.4
1 69 4.4
26 52 <0.1
58 -----12 14 71 10.5
6.6 89 9.8
73 9.6
76 8.9
79 8.8
76 5.2
77 4.2
64 4.7
72 4.6
71 3.3
86 7
81 5
63 1.7
38 0.4
1.4 NA 1.7 48 0.1 ---------53 <0.1 ---
59 <0.1
59 <0.1
58.1 <0.1
4.21 49.8 <0.1
54.4 <0.1
56.6 1.37
66.8 3.16
80.7 4.94
80 5.1
NA NA
92.1 8.4 ·-·-ss 4.3
61 1.06
65.8 1.18
58.3 1.69
56.5 1.63
61.3 1.89
60 2.20
66.7 2.78 --62.2 iis
60.6 1.81
67.1 2.63
54.2 2.12
1.9 J 64 ___ 2.00
85.1 4.55
84.7 4.51
62.5 2.83
73 2.53
68.8 2.88
66.3 f35
71.5 2.43
72.9 3.55
88.6 3.37
84.1 3.12
76'.2 3.91
79.7 4.44
77.4 4.74
85.9 5.73
85.6 5.74
87.0 0.37 H
92.6 5.82
87.4 6.74
77.4 4.74
89.9 4.85
84.3 5.0
93.2 4.2
89.8 4.41
91.0 4.75
88.5 5.69
92.5 5.09
94.2 5.0
91.9 4.93
TABLE 1 (19 of 33) Historic Summary Of Monitoring Well Analytical Results Up To The 3rd Quarter 2023 Chloroform Contamination Investigation DUSA White Mesa Mill
Parameter Sampling Event IGWCSI Chloroform Chloromethane Methylene Chloride
1st Ctr 2nd Qtr 3rd Qtr 4th Ctr 1st0tr 2nd Ctr 3rd0tr 4th Ctr 1stQtr 2nd Qtr 3rd Qtr 4th0tr 1stQtr 2nd Ctr 3rd Ctr 4th Ctr 1st Ctr :;{Ctr Ctr Ctr 1stQtr 2nd Ctr 3rd Ctr 4th Ctr 1st0tr 2nd Qtr 3rd Qtr
3/16/2005 5/25/2005 8/31/2005 12/7/2005 3/9/2006 6/14/2006 7/20/2006 11/8/2006 2/28/2007 6/27/2007 8/15/2007 10/10/2007 3/28/2008 6/25/2008 9/10/2008 10/15/2008 3/4/2009 6/23/2009 9/14/2009 12/17/2009 3/24/2010 . 6/14/2010 8/12/2010 10/15/2010 2/22/2011 5/26/2011 8/17/2011
(1) 12/7/2011 (2) 1/18/2012
(5 µg/L)
NA NA <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 -<"f:(l <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 NA <1.0 <1.0
(70 µg/L) (30 µg/L) (5 µg/L) 38 NA NA 29.8 NA NA 39 2.8 <1.0 14 1.1 <1.0 12 1.6 <1.0 12 2.7 <1.0 10.8 <1.0 <1.0 12.5 <1.0 <1.0 9.2 <1.0 <1.0 8 <1,0 <1.0 8.9 <1.0 <1.0 7.4 <1.0 6.4 <1.0 <1.0 5.7 <1.0 <1.0 8 <1.0 <1.0 9.4 <1.0 <1.0 11 "<1.o <1.0 16 <1.0 <1.0 13 <1.0 <1.0 8.2 <1.0 <1.0 69 <1.0 <1.0 29 <1.0 <1.0 29 <1.0 <1.0 30 <1.0 <1.0 39 <1.0 <1.0 26 <1.0 <1.0 29 <1.0 <1.0 NA NA NA 28 <1.0 <1.0 25 <1.0 <1.0 i;i•···· 11/16/2011
r ---6/13/2012 <1.0 ---------24 <1.0 ______ <1.0 -----3rdQtr 9/11/2012 <1.0 38 <1.0 41h Ctr 10/3/2012 <1.0 30 <1.0 1stQtr 2/13/2013 <1.0 34.9 <1.0 2nd Qtr 6/13/2013 <1.0 37.9 <1.0 3rdQtr 9/5/2013 <1.0 41 <1.0 4th Qtr 11/13/2013 <1.0 <1.0 1stQtr 1/30/2014 <1.0 6.93 <1.0 2nd Qtr 5/22/2014 <1.0 6.93 <1.0 3rdQtr 8/14/2014 <1.0 32.8 <1.0 4th Ctr 10/28/2014 <1.0 33 <1.0 1stQtr 3/12/2015 <1.0 32 <1.0 2nd Qtr 6/11/2015 <1.0 30.5 <1.0 3rdQtr 9/3/2015 <1.0 28.7 <1.0 4th Qtr 10/28/2015 <1.0 52.9 <1.0 1stQtr 3/17/2016 <1.0 56.6 <1.0 2nd Qtr 6/8/2016 <1.0 60 <1.0 3rdQtr 8/3/2016 <1.0 56.3 <1.0 4th0tr 10/26/2016 <1.0 60.1 <1.0 1StOtr 3/16/2017 <1.0 62 <1.0
Duplicate TW4-75 <1.0 61.5 <1.0 2nd Qtr 6/20/2017 <1.0 63.8 <1.0 3rd Qtr 8/3/2017 <1.0 62.8 <1.0
Duplicate TW4-75 <1.0 62.3 <1.0 4thQtr 10/11/2017 <1.0 62.9 <1.0 1stQtr 3/1512018 <1.0 62.3 .<f"O 2nd Qtr 6/13/2018 <1.0 59.9 <1.0 3rd Qtr 8/30/2018 <1.0 56.2 <1.0 4th Ctr 12/13/2018 <1.0 57.6 <1.0 1stQtr 3/19/2019 <1.0 52.8 <1.0 2nd Qtr 6/19/2019 <1.0 54.2 <1.0
Dupl1eateTW4-75 <1.0 54.4 <1.0 3rd Qtr 9/11/2019 <1.0 56.2 <1.0 4thQtr 12/18/2019 <1.0 62.0 <1.0 1st0tr 3/18/2020 <-1.0 57.0 <1.0 2nd Qtr 6/12/2020 <1.0 58.2 <1.0 3rd Qtr 9/18/2020 <1.0 60.0 <1.0 4th Qtr 11/11/2020 <1.0 58.6 <1.0
DWMRC solit samole <10 56.0 <20 1s1Qtr 3/18/2021 <1.0 52.0 <·1.0 2nd Qtr 6/16/2021 <1.0 58.2 <1.0 3rdQtr 9/22/2021 <1.0 49.9 <1.0 4th Qtr 12/8/2021 <1.0 57.0 <1.0 1stQtr 3/2312022 <1.0 <1.0 2nd Qtr 6/22/2022 <1.0 62.9 <1.0 3rd0tr 9/14/2022 <1.0 60.6 <1.0 4th Qtr 12/9/2022 <1.0 62.6 <1.0
Dualicate TW4-75 <1.0 67.9 <1.0 -.i"St Otr 3/29/2023 <1.0 54.4 <1.0 2nd Qtr 6/21/2023 <1.0 54.6 <1.0 3rdQtr 9/14/2023 <1.0 55.5 <1.0
(1) voes were resampled because laboratOf}' missed holding time (2) As of Ma.rch 2012 both north and south wild llfe ponds no longer receiving water.
NA:notanalvzed ________ ------
Shaded indicates concentratJoos exceedin!l GWOS.
<1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 ·<·1:·o <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <20 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0
Chloride No GWCS (mg/L) NA NA NA 41 36 35 35 34 30 28 32 27 23 23 26 30 29 30 26 30 41 35 37 50 52 36 23 23 NA 18 ---------30 26 27 23.1 22.9 36.2 37.1 38.9 47 49 40.8 41.6 43.5 47.6 39.4 40.7 43.8 40.7 43.9 394" 41.1 41.6 40.4 41.5 37.1 4f3 39.5 45.6 38.2 37.6 39.5 40.8 36.8 42.7 39.4 41.4 38.7 39.6 41.0 41.8 41.4 29.8 41.1 39.1 48.1 44.7 45.2 45.6 47.1 45.8
Nitrate, Nitrate+ Nitrite (10mg/L) 14.1 12.9 13.3 7.3 5.9 4.7 6.1 5.7 5.1 4.9 5.0
4.4 0.7 4.6 4.9 5.2 5.2 6.2 5.9 5.4 51 9.0 9.0 10.0 10.0 9.0 4.6 6.3 NA 4.4 6.6 6.6 6.0 5.6 8.9 12.1 14.2 12.B 12.2 9.8 11.1 11.7 9.69 15.7 6.24 5.96 5.45 5.79 5.24 4.47 4.41 4.50 4.24 4.31 4.43 432 4.09 3.51 3.60
4.01 2.95 3.25 3.02 3.71 3.62 3.36 3.67 3.30 3.61 3.62 3.37 3.90 3.4 3.4 3.46 3.60 3.63 3.40 3.40 3.84
TW4-19
(chlOfofrom pumping well started
4/30..03) Sampling Event
1st0tr 3/16/2005
2nd Qtr 5/25/2005 3rdQtr 8/31/2005 4th Qtr 1217/2005
1stQtr 3/9/2006 2nd Otr 6/14/2006
3rd Qtr 7/20/2006
4th Ctr 11/8/2006
1stOtr 2/28/2007 2nd Qtr 6/27/2007
3rd Qtr 8/15/2007 4th Qtr 10/10/2007 1s!Qtr 3128/2008 2ndOtr 6/25/2008 3rd Qtr 9/10/2008
4thQtr 10/15/2008 1s!Qtr 3/4/2009 2ndOtr 6/23/2009
TABLE 1 (20 of 33)
Historic Summary Of Monitoring Well Analytical Results Up To The 3rd Quarter 2023
Chloroform Contamination Investigation
DUSA White Mesa Mill
Parameter
(GWQS)
Carbon Tetrachloride Chloroform Chloromethane Methylene Chloride Chloride
(5 "g/L) (70 "n/L) (30 ug/L) (5 "n/L) No GWQS (mo/LI
NA 2.200 NA NA NA
NA 1,200 NA NA NA <5.0 1.400 <5.0 <5.0 NA
2,800 81
1,200 86 1,100 116
1.120 123
1.6 1.050 2.6 <1.0 134
1.3 1.200 <1.0 <1.0 133 Did not sample
1.9 1,100 <1.0 <1.0 129
1.9 1.100 <1.0 <1.0 132
2.9 1.800 <1.0 <1.0 131
<1.0 1.000 <1.0 <1.0 128
8.6 3.600 <1.0 <1.0 113
12 4,200 <1.0 <1.0 124
1.2 1.ioo <1.0 �-1.0 127
1.2 990 <1,0 <1.0 132
Nitrate, Nitrate+ Nitrite
(10mg/L)
5.3
5.7
4.6
<0.1
4
5.2
4.3
4.6 4
4.1 4
2.2
2.8
35.2
47.8
3.2 2.4
3rd Qtr 9/14/2009 15 6,600 <1.0 <1.0 43 <0.1
4thQtr 12/22/2009
1stOtr 2/17/2010 2ndQtr 6/14/2010 3rd Ctr 8/16/2010
1�1_1}_ _ _9tr 10/15/2010
1stOtr 2/17/2011 2nd Otr 6/7/2011 3rdQtr 8/17/2011
4thOtr 11/16/2011
2nd Qtr ----6/6/2012 3rdOtr 9/4/2012
4th Otr 10/3/2012 1stQtr 2/13/2013
2nd Qtr 6/5/2013 3rd Qtr 9/3/2013
4th Otr 10/29/2013 1stQtr 1/2712014 2nd Qtr 5/19/2014 3rd Qtr 8/11/2014 4thOtr 10/21/2014
3/9/2015 2nd Qtr 6/8/2015
3rd Qtr 8/31/2015
4thOtr 10/19/2015 1stQtr 3/9/2016
2ndOtr 5/26/2016 3rd Qtr 7/25/2016 4thQtr 10/13/2016 1st Ctr 3/8/2017
2nd Qtr 6/13/2017 3rd Otr 7/26/2017
4thQtr 10/11/2017
1stQtr 3/12/2018
2nd Qtr 6/8/2018 3rd Qtr 8/30/2018
4thOtr 11/28/2018 1stQtr 3/f/2019
2nd Qtr 6/5/2019 3rdOtr 9/4/2019
4thQtr 12/10/2019 1st Ctr 2/19/2020
2nd Qtr 5/27/2020 3rd Ctr 9/4/2020
4th Ctr 10/28/2020 1st Ctr 2/23/2021
2nd Qtr 6/9/2021 3rd Ctr 8/24/2021
4th Qtr 12/1/2021
1stQtr 3/9/2022
2nd Otr 6/8/2022
3rd Ctr 8/30/2022
4th Qtr 11/30/2022 1st Ctr 3/7/2023
2nd Qtr 6/13/2023 3rd Ctr 8/9/2023
16
1.3
4.2
4.9
1.3 17
8.3
2.1
5.4
1.5
1.1
3.5
4
5.15
5.15
20.7
6.42 4.05
5.51
1.9
4.8
8.92
2.62 <1.0
12.2
13.5
23.1
9.89 10.8
3.06
1.35 13.0 <1.0 1.36
3.45 2.03
6.18
2.43 15.9
10.1 <1.0 13.7 10.4
1.98
1.1
8.4
<1.0 7.83
13.2
<1.0
2.7
2.5 8.0
<1.0 3.1
2.5
(1) voes were resampled because laboratory missed holding time
4.700
940
1.800
2,000 1.200
3.400
4.000 970
2.200
650
----460 950
1500
4,210
2.070
8,100
942
-586
810
1.410
4,310
4.660
1.570 7,860
7,840
7.780 12,600
6,040
6.640 1,240 510
8.840
129
2,640
2,980
1,910
5.270
2.050 11,500
6,670 551
8.720
7.600
1.350
660
6,660
775
4.450
6,950 ---654
2,540
4.750
7,380
230
4.850 198
<1.0 <1.0 <1.0 <1.0
<1.0 <1.0 <1 .0 <1.0
<1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<TO ______ <1.0 ----
<1.0 <1.0 <1.0 <1.0 <1.0 <1.0
<1.0 <1.0 <1.0 <1.0
<1.0 <1.0
<1.0 <1.0 <1.0 <1.0 8.3 <1.0 <1.0 <1.0
<1.0 <1.0 <1.0 <1.0
7.78 <1.0
5.46 <1.0 1.4 <1.0 <1.0 <1.0 <1.0 <1.0
<1.0 <1.0 <1.0 <1.0
<1.0 <1.0
<1.0 <1.0 <1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0 <1.0 <1.0 <1.0 <1.0
<1.0 <1.0 <1.0 <1.0 <1.0 <1.0
5.41 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
5.41 <1.0
<1.0 <1.0
1.98 1.25
<1.0 <1.0
<1.0 <1.0
4 <1.0 <1.0 <1.0
<1.0 <1.0
<1.0 <1.0 3.4 <1.0 <1.0 <1.0
(2) As of March 2012 both north ,1nd south wild life ponds no longer receiving water. _____ _
NA = not analyzed
Bold and �alics Indicates lhe MOL exceeded the GWQS.
Shaded indicates concentrations exceedi� GWOS
124 26.7
144 2
132 4.4
142 5.9
146 2.7
135 17.0
148 12.0
148 3.0
148 5.0
138 0.6 ---------149 2.4
149 2.5
150 4.1
164 8.0
148 3.0
179 17.6
134 4.7
134 1.6
152 1.3
140 1.6
130 4.7
238 8.56
180 0.916
326 11.6
252 10.6
276 15.70
204 1.27
214 10.5
200 10.0
461 11.1
135 0.243
218 1.120
139 0.377
193 8.6
138 0.494
166 2.55
140 0.233
197 6.58
160 8.96
153 0.33
147 0.535
205 10.1
147 1.14
188 11.6
104 1.1
167 6.6
115 4.04
172 6.68
184 11.0
119 1.7
128 1.4
178 4.76
129 3.6
122 1.75
167 6.7
122 1.57
TABLE 1 (21 of 33) Historic Summary Of Monitoring Well Analytical Results Up To The 3rd Quarter 2023 Chloroform Contamination Investigation OUSA White Mesa Mill
TW4-20 Parameter (chkll'oform pumping wel started (GWQS)
Sampling Event Carbon Tetrachloride Chloroform Chloromethane Methylene Chloride (5 µg/L) (70 µg/L) (30 µg/L) (5 µg/L) 1stQtr 3/16/2005 Monitor well was not installed 2nd Qtr (3) 5/25/2005 3rd at,----8/31/2005 4th Qtr 12ll/2005 1stOtr 3/9/2006 2nd Qtr 6/14/2006 3rd Qtr 7120/2006 4thQtr 11/8/2006 1stOtr 2nd Qtr 6/2712007 3rd Qtr 8/15/2007 4th Ctr 10/10/2007 1stQtr 3/28/2008 2nd Ctr 6/25/2008 3rd Ctr 9/10/2008 4th Qtr 10/15/2008 1st Ctr 3/4/2009 2nd Qtr 6/23/2009 3rd Ctr 9/14/2009 4th Qtr 12/22/2009 1st Ctr 2/17/2010 2ndQtr 6/14/2010 3rd Qtr 8/16/2010 4th Ctr 10/15/2010 1st Ctr 2/17/2011 2nd Ctr 6/7/2011 3rd Qtr 8/17/2011 4thOtr 11/16/2011 1st Citr (2) 1/23/2012 2nd Qtr ----6/6/2012 3rdOtr 9/4/2012 4th Qtr 10/3/2012 1stOtr 2/11/2013 2ndOtr 6/5/2013 3rd Qtr 9/3/2013 4thOtr 10/29/2013 1stOtr 1/27/2014 2ndQtr 5/19/2014 3rdOtr 8/11/2014 4th Ctr 10/21/2014 1stOtr 3/9/2015 2nd Qtr 6/8/2015 3rdOtr 8/31/2015 4th Qtr 10/19/2015 1stOtr 3/9/2016 2nd Otr 5/23/2016 3rd Otr 7/25/2016 4th Ctr 10/12/2016 1st"·Cur 3/8/2017 2nd Ctr 6/13/2017 3rd Qtr 7/26/2017 4th Ctr 10/12/2017 1st Ctr 3/12/2018 2nd Ctr 6/14/2018 3rd Ctr 8/22/2018 4th Ctr 11/28/2018 1st Ctr 3/8/2019 2nd Ctr 6/5/2019 3rd Ctr 9/4/2019 4th Qtr 12/10/2019 1st Ctr 2/19/2020 2nd Ctr 5/27/2020
NA
<10
<500
<500
<1000 7.1 3.1 2.2 3.5 6.8 9 13 15 NA 5.7 4.9 8.4 14 2.7 11 12 20 27 10 7.3 7.2 10 ----------33 26 22 19.6 32.5 25.7 17.3 18 4 22.1 14.1 18.5 20.8 16.2 15.1 14.5 20.2 40.6 26.6 24.4 23.5 23.4 25.0 11.2 15.9 <1.0 9.85 8.32 15.4 10.1 8.39 5 92 86 6.74
•-39,000 NA NA 3,800 <10 ------<10 19,000 <250 <250 9,200 <500 <500 61,000 <500 5,300 <1000 <1000 11.000 1.9 2.2 4.400 <1.0 1.1 1.800 <1.0 <1.0 5.200 <1.0 1.8 9.000 <1.0 1.9 13.000 <1.0 1.5 30.000 <1.0 1.2 21.000 <1.0 3.7 NA NA NA 8.200 <1.0 5.2 6.800 <1.0 4.2 13.000 <1.0 4.4 15,000 <1.0 3.0 3.500 <1.0 3.2 18.000 <1.0 3.7 15,000 <1.0 2.2 24.000 <1.0 5.5 31.000 <1.0 19.0 8.100 <1.0 2.1 3.800 <1.0 3.1 7.900 <1.0 2.5 11,000 <1.0 1.3 ---36]00 <1.0 13.000 <1.0 <1.0 19.000 <1.0 <1.0 18,500 <1.0 1.21 26.300 <1.0 1.3 26.800 <1.0 2.14 15.700 <1.0 1.37 17.800 <1.0 2.04 22.100 2.31 3.98 12.400 55.2 2.2 23.300 4.04 2.38 19.900 4.85 1.38 17.600 13.4 1.73 17.000 12.3 <1.0 17.000 10.8 1 21.600 4.09 1.16 33.700 <1.0 <1.0 23.600 <1.0 <1.0 21,300 <1.0 <1.0 23.400 <1.0 <1.0 18.100 <1.0 <1.0 27.600 1.25 <1.0 11,600 2.34 <1.0 15.400 1.77 2.36 12.000 <1.0 7.77 10.500 4.98 <1.0 9.500 15.6 <1.0 15.600 <1.0 <1.0 13.700 <1.0 <1.0 10.500 <1.0 <1.0 8.790 2.67 <1.0 14.300 10.7 <1.0 5.800 1.3 12.3 Well TW4•20 Abandoned in October 2020 (1) VOCs were re&ampled because laboratory missed holding time (2) As of March 2012 both north and south wild life ponds no k>nger receiving water.
JJ) Chloroform� well stalled 81.WS NA"' not analyzed Bold and rtatics indicates the MOL exceeded the GWQS Shaded indicates concentratoos exceeding GWQS.
Chloride Nitrate, Nitrate+ Nrtrite No GWQS lmo/L) (10mg/L)
NA I 10.10
NA --------------------2.90 131 1.80 120 3.80 235 9.40 134 2.90 124 3.50 124 4.20 112 2.30 117 2.10 170 5.60 132 0.90 191 8.00 156 4.44 168 5.51 164 5.10 164 2.90 153 3.30 187 5.30 179 2.00 200 5.60 196 5.30 203 4.60 220 4.40 177 4.80 207 6.50 186 4.20 2lii 7.90 ---------262 ----------11.00 289 10 80 302 11.00 252 9.07 250 9.80 260 8.65 272 9.64 254 7.56 269 5.95 299 4.30 292 7.67 290 9.80 296 5.76 365 9.3 293 6.23 293 10.30 318 11.2 307 11.3 301 11.4 296 12.0 281 9.76 292 10.8 293 8.91 289 9.5 258 10 40 282 8.14 295 9.72 272 6.7 279 9.59 286 10.20 307 9.75 310 9.81 3.01 7.23
TABLE 1 (22 of 33)
Historic Summary Of Monitoring Well Analytical Results Up To The 3rd Quarter 2023
Chloroform Contamination Investigation
DUSA White Mesa Mill
1W4-21 Parameter
(GWCS) (chlofoform pumping well 619/15)
Sampling Event Carbon Tetrachloride Chloroform Chloromethane Methylene Chloride
(5 µgill 170 ua/L) (30 µ9/L) (5 µg/L)
1st0tr 3/16/2005 Monitor well was not installed
2nd Qtr 5/25/2005
3rd Ctr 8/31/2005
4th Ctr 12/7/2005
1stQtr 319/2006 2nd Qtr 6/14/2006
3rd Ctr 7/20/2006
4th Ctr 11/8/2006
1st0tr 2/28/2007
2ndQtr 6/27/2007
3rd0tr 8/15/2007
4th Ctr 10/10/2007
1s1Qtr 3/28/2008
2nd Qtr 6/25/2008
3rdQtr 9/10/2008
4th Qtr 10/15/2008
11/18/2008
1st0tr 3/11/2009
2nd0tr 6/23/2009
3rd Qtr 9/14/2009
4th Ctr 12/22/2009 1st Ctr 2/25/2010
2nd Ctr 6/14/2010
3rd Qtr 8/13/2010
4th Ctr 10/15/2010
1st Ctr 2/22/2011
2nd Ctr 6/28/2011
3rd Otr 8/17/2011
4thQtr 11/16/2011
1217/2011 1st utr (2) 1/23/2012
2nd Ctr ----6/6/2012
3rd0tr 9/4/2012
4th Ctr 10/3/2012
1stQtr 2/11/2013
2ndQtr 6/5/2013
3rd Qtr 9/3/2013
4th Ctr 10/29/2013
1stQtr 1/27/2014
2nd Qtr 5/19/2014
3rd Otr 8/11/2014
4thQtr 10/21/2014 1stQtr 3/9/2015 2nd Ctr (3) 6/8/2015
3rd Qtr ____ 8/31/2015
4th0tr 10/19/2015
1stQtr 31912iHs 2ndQtr 5/23/2016 3rd0tr 7/25/2016
4th Ctr 10/12/2016
1st0tr 3/8/2017
2nd0tr 6/13/2017
3rd Qtr 7/26/2017
4th Ctr 10/11/2017
OWMRC MIii umole
1st0tr 3/12/2018
2nd Qtr 6/8/2018
3rdQtr 8/22/2018
4th Ctr 10/22/2018
1stQtr 3/8/2019 2nd Qtr 6/5/2019
3rd0tr 9/4/2019
4th Ctr 12/10/2019
1st0tr 2/19/2020
2nd Qtr 5/27/2020
3rd0tr 9/4/2020
4thQtr 10/28/2020
1st Ctr 2/23/2021
2nd Otr 619/2021
3rdQtr 8/24/2021
4th Ctr 12/1/2021
1st0tr 319/2022
2nd Otr 6/8/2022
3rdQtr 8/30/2022
4th Ctr 11/30/2022
1stQtr 3/7/2023
NA
<5.0
<1.0
<2.5
<2.5
<2.5
2
1.8
58
<1.0 <1.0
7
1.7 1.6
NA
2
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0 9.2
1.2
1.2
4.8
6.3
6.7
6.4
5.4
6
7
5.25
3.49
2.13
<1.0 6.23 4.73
<1.0 1.04
1.75
1.92
<1.0-------
<1.0
<1.0
<1.0 <1.0
<1.0
2.36
1.16
1.05
<1.0
<3.8
2.36
<1.0
<1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0
<1.0
<1.0 <1.0 <1.0
<1.0
<1.0 <1.0
<1.0 <1.0
192 NA NA
78 <5.0 <5.0
86 <1.0 <1.0
120 <2.5 <2.5
120 <2.5 <2.5
108 <2.5 <2.5
139 <1.0 <1.0
160 <1.0 <1.0
300 <1.0 <1.0
140 <1.0 <1.0
120 <1.0 <1.0
390 <1.0 <1.0
180 <1.0 <1.0
120 <1.0 <1.0
#N/A NA NA
170 <2.0 <2.0
180 <1.0 <1.0
200 <1.0 <1.0
200 <1.0 <1.0
160 <1.0 <1.0 170 <1.0 -c"1.o
210 <1.0 <1.0
390 <1.0 <1.0
200 <1.0 <1.0
230 <1.0
290 <1.0 <1.0
460 <1.0 <1.0
390 <1.0 <1.0
420 <1.0 <1.0 ----400 <1.0------<1.0 -----
410 <1.0 <1.0
390 <1.0 <1.0
282 <1.0 <1.0
328 <1.0 <1.0 244 <1.0 <1.0
204 <1.0 <1.0
220 <1.0 2.04
240 <1.0 2.04
204 <1.0 <1.0
229 <1.0 <1.0 292 <1.0 <1.0 366 <1.0 <1.0 ----281 <1.0------<1.0 ------
339 <1.0 <1.0
390 <1.0 <1.0
545 <1.0 <1.0
456 <1.0 <1.0
456 <1.0 <1.0
598 <1.0 <1.0
224 <1.0 <1.0
537 <1.0 <1,0
466 <1.0 <1.0
400 <6.0 14 J
421 <1.0 <1.0
532 <1.0 <1.0
476 <1.0 <1.0
585 <1.0 <1.0
323 <1.0 <1.0
734 <1.0 <1,0
596 <1,0 <1.0
794 <1.0 <1.0
844 2.58 <1.0
767 <1.0 <1.0
920 <1.0 <1.0
948 <1.0 <1.0
400 <1.0 <1.0
1.130 <1,0 <1.0
669 <1.0 <1.0
649 <1.0 <1.0
469 <1.0 <1.0
657 <1.0 <1.0
1,070 <1.0 <1.0
482 <1.0 <1.0
469 <1.0 <1,0
2nd Otr 6/13/2023 <1.0 657 1.4 <1.0
3rd0tr 8/9/2023 <1.0 49.7 <1.0
(1) VOCs were reaampled beceuse laboratory missed holdmg ttme. (2) As of March 2012 both north and south wild life ponds no longer receiving waler.
(�Chlofoformpumpngwelstar1ed6/9/15 -------------------------
'"NA�nol'anaivzed
Shaded indicates concentrations eKceedina GWOS.
J "Approximated value
<1.0
Chloride Nitrate, Nitrate+ Nitrite
No GWCS lmo/L) I10ma/L)
NA 14.6
NA 10 1
353 9.6
347 8.5
318 10 2
357 8.9
296 8.7
306 8.7
327 8.6
300 8.6
288 8.3
331 14 3
271 8.8
244 7.57
284 8.0
NA #NIA
279 8.3
291 8.1
281 9.2
256 8.4
228 8.4
266 12 0
278 14 0
210 7.0
303 9.0
290 12 0
287 14 0
287 13 0
228 15.0 ---------285 -----------11 0
142
270
221 243 207
206 200
243
230
252 255 494 ---------499
413
452
425 457
439
452
309
447
378
310 447
387
182
392
180
456
478
339
446 353
382
411 454
461 375 227
110
331 425
158 335
397
161
13 0
14 0 11 8
13 8 10 3 9.0 11 4
11.5
7.1
10 0
10.9
13 1 ---14 7
14.3 14 6 13 1
16 5 13 5
177
9.53
18.20
16 90
11
15 8
14 1
0.236
15.2
8.99
17.5
14 7
5.73
8.93
15 4
12 6
16 3
15.20
21.5 12.9
17.2
2.2
8.9
14 3 2.12
10 9
17 3
6.13
TABLE 1 (23 of 33)
Historic Summary Of Monitoring Well Analytical Results Up To The 3rd Quarter 2023
Chlorofonn Contamination Investigation
TW4-22
(nrtrate pumpmg well started
1126/13)
Sampling Event
1stQtr 3/16/2005
2nd Ctr 5/25/2005
3rd Qtr 8/31/2005 4thQlr 12/7/2005
1st Ctr 3/9/2006
2ndQtr 6/14/2006
3rd Qtr 7/20/2006 4thQtr 11/8/2006
1stQtr 2/28/2007
2nd Ctr 6/27/2007
3rd Qtr 8/15/2007 4thQtr 10/10/2007
1st Ctr 3/28/2008
2nd Ctr 6/25/2008
3rd Qtr 9/10/2008
4thQtr 10/15/2008 11/18/2008
1st Ctr 3/11/2009
2ndQtr 6/23/2009
3rd Ctr 9/14/2009
4thQtr 12/29/2009
1st0tr 3/23/2010
2nd Qtr 6/14/2010
3rdQtr 8/24/2010
4th Ctr 10/15/2010
1st Ctr 2/22/2011
2nd Qtr 6/1/2011
3rdQtr 8/17/2011 4th Qtr 11/16/2011 �1l 121112011 ---2) --1/1912012
2nd Qtr 6/13/2012
3rd0tr 9/12/2012 4th Ctr 10/4/2012 1stQtr(3) 2/11/2013
2nd Otr 6/5/2013
3rd0tr 9/3/2013
4thQtr 10/29/2013
1st Ctr 1/27/2014
2nd Qtr 5/19/2014
3rd0tr 8/11/2014 4thQtr 10/29/2014
1st Ctr 3/9/2015
2nd Qtr 6/8/2015
3rd0tr 8/31/2015 4th Qtr 10/19/2015
1st Ctr 3/9/2016
2nd Otr 5/23/2016
3rdQtr 7/25/2016 4thQtr 10/12/2016
1st Ctr 3/8/2017
2nd Qtr 6/13/2017
3rd Ctr 7/26/2017
4th Qtr 10/11/2017
DWMRC s...a;. ... ......a..
1st Ctr 3/1 2/2018
2nd Qtr 6/8/2018
3rd Ctr 8/22/2018 4thQtr 11/28/2018
1st Ctr 3/8/2019
2nd Qtr 6/5/2019
3rd0tr 9/4/2019 4thQtr 12/10/2019
1st Ctr 2/19/2020
2nd Qtr 5/27/2020
3rd0tr 9/4/2020
4thQtr 10/28/2020
1st0tr 2/23/2021
2nd Qtr 6/9/2021
3rdQtr 8/24/2021
4th Ctr 12/1/2021
1stQtr 3/9/2022
2nd Qtr 6/8/2022
3rd0tr 8/30/2022
4th Ctr 11/30/2022
1st0tr 317/2023
2nd Qtr 6/13/2023
3rd0tr 8/9/2023
Carbon Tetrachloride
NA
<5.0
<5.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0 1.3
NA
<2.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0 1.2
<1.0
<1.0
NA
<1.0
<1.0
<1.0
<1.0
<1.0
3.24 3.35 3.25 8.09 6.06 6,65 1.9 3.32 3.77
2.42
<1.0 3.32
<1.0 2.64
<1.0 1.08 1.56 1.21
<1.0
<1.0
<38
<1.0
<1.0
<1.0
<1.0 1.02 1.13
<1.0
<1.0 1.02
<1.0
<1.0 6.83
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
DUSA White Mesa Mill
Parameter (GWQS)
Chlorofonn Chloromethane Methylene Chloride 170 •o/L) (30 ug/L) •olL) Monitor well was not installed 340 NA NA 290 <5.0 <5.0 320 <5.0 <5.0
390 <10
280 <10
864 <10 350 1.6 <1.0 440 <1.0 <1.0 740 <1.0 <1.0 530 <1.0 <1.0 440 <1.0 <1.0
1,400 <1.0 <1.0 1,200 <1.0 <1.0 6,300 <1.0 <1.0
#NIA NA NA 630 <2.0 <2.0 390 <1.0 <1.0 730 <1.0 <1.0 2,300 <1.0 <1.0 380 <1.0 <1.0 2,200 <1.0 <1.0 540 <1.0 <1.0 340 <1.0 <1.0 340 <1.0 <1.0 1,300 .<1.0 <1.0 210 <1.0 <1.0 450 <1.0 <1.0 #N/A NA NA 400 <1.0 <1.0 200 <1.0 <1.0
<TO ______ <1.0 -----
121 330
12.500 9.640 13,300 12.100
12.400 12 .400 12.400 12.700 8.050 7,810 7,530 6,070 8,570 5,840 3,370 5,320 3,670 5,150 4,770 4.100 4,530 3,010 3,600 2,680 4,310 4,690
3.460 3.820 3,910 2.530 3,760 3,640 5,100
4,520 3,510 3,330 3,320 2,600 3,190 2,350 1,900 2.180 1 890
<1.0 <1.0
<1.0 <1.0
<TO ______ <1.0 -----
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 2.83
<1.0 <1.0
40 <1.0 1.61 <1.0 4.31 <1.0 3.42 <1.0 5.47 <1.0
5.1 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<60 150J
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
-:::1:0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
4.4 <1.0
<1.0 <1.0
<1.0 1.6
<1.0 1.3 3.3 2.1
<1.0 1.9
(1) VOCs ·wen, resampled because laboratory missed holdmg tme
(21 As of March 2012 both north and south wild life ponds no longer receiving waler.
(�Chloroform..fUTP.!2_welstafted 1126113 _______ _ NA•notanatvzed
Shaded Incllcatn concentratJons exceed� GWCS.
Bold and italics indicates the MOL exceeded the GWCS.
J ,. Aooroxunated value
Chloride Nitrate, Nitrate+ Nitrite No GWQS lmn/LI 110mg/L)
NA 18.2
NA 15.7 253 15.1 236 15.3 221 14.3 221 14.5 236 15.9 347 20.9 273 19.3 259 19.3 238 18.8
519 39.1 271
524 38.7 539 36.3
NA #NIA 177 20 7 177 20.6 391 40.3 175 17.8
427 36.8 134 19.0 130 15.0
134 16.0 114 18.0 138 17.0 120 15.0 174 19.0 NA #N/A 36 14.0
7.0 . 351 -12 8
_________ 130 ___________ 14.0 130 58.0
586 50.2
487 29.7 501 45.2
598 54.6 614 47.2 540 41.5
596 54.9 675 69.2 390 47 1 557 64.7 567 56.1 5°s:i 31.1 598 58.4 619 61.3
588 61.5 566 69.8 572 70.8 391 66.1 600 80 1 610 79 0 607 62.3
580 72 5 613 55 4 567 75.7
528 71 9 662 83 9
588 72 5
608 59 9 606 57 .7
578 60.5 514 64.8 523 64.9 618 69 .6
408 89.3 410 35.1
586 68.8
442 40.4
564 45 0 637 69.9 601 62.0 562 49.1
596 49.8 617 58.8
TW4-23 Sampling Event
TABLE 1 (24 of 33) Historic Summary Of Monitoring Well Analytical Results Up To The 3rd Quarter 2023 Chlorofonn Contamination Investigation OUSA White Mesa Mill
Parameter IGWQSI Carbon Tetrachloride 15 µg/L) Chlorofonn Chloromethane Methylene Chloride Chloride Nitrate, Nitrate+ Nitrite
2nd Qtr 3rdQtr 4th Qtr
1 stQtr 2nd Qtr 3rd Qtr 4th Qtr
170 µg/L) (JO µg/L) 15 µg/L) No GWQS lmg/L) (10 moil) .. 6/27/2007 <1.0 <1.0 <1.0 <1.0 47 <0.1 8/15/2007 <1.0 <1.0 <1.0 <1.0 46 <0.1 10/10/2007 <1.0 <1.0 <1.0 <1.0 43 <0.1 3/28/2008 <1.0 <1.0 <1.0 <1.0 41 <0.1 6/25/2008 <1.0 <1.0 <1.0 <1.0 41 <0.1 9/10/2008 <1,0 <1.0 <1 .0 <1.0 35 <0.05 10/15/2008 NA NA NA NA 51 <0.05 11/18/2008 <2.0 <2.0 <2.0 <2.0 NA NA 1st Ctr 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 Ctr 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 fstOtr 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 3rdQtr 8/24/2010 <1.0 <1.0 <1.0 <1.0 40 <0.1 ���g:; 1���"�·�"�+:°')"':�'----------lf':'"�:�'-------lf':'"�:"�----t-::.c)"':�'-------+-------'!"'!+::s�c,:�--------ll 2nd Qtr 6/1 4/2011 <1.0 <1.0 <1.0 <1.0 44 <0.1 3rd0tr 8/16/2011 <1.0 <1.0 <1.0 <1.0 41 <0.1 4th Otr 11/15/2011 <1.0 <1.0 <1.0 <1.0 43 <0.1 Tsl(Itr(1·1 111112012 <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 <0.1 ---3rd Ctr 8/29/2012 <1.0 <1.0 <1.0 <1.0 46 <0.1 4th Qtr 10/3/2012 <1.0 <1.0 <1 .0 <1.0 45 <0.1 1st0tr 217/2013 <1.0 <1.0 <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 3rdQtr 9/5/2013 <1.0 <1.0 <1.0 <1.0 48 <0.1 4thQtr 11ll/2013 <1.0 <1.0 <1.0 <1.0 43 <0.1 1stQtr 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 Ctr 8/13/2014 <1.0 <1.0 <1.0 <1.0 46 <0.1 4th Ctr 10/28�/2�0�1 �41-<�1 .=0 _____ --+<�1.,�0 __ -+<.:.1ec.0,__ ___ +:<-"1.,c_0 _____ +--------"46e,.,c8e::<"-O.ce1_ 1st Qtr 3/12/2015 <1.0 <1.0 <1.0 <1.0 47.3 <0.1 2nd Qtr 6/8/201 5 <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 p��!�IW�.�10 <1.0 <1.0 <1.0 <1.0 4469 .. 41 <<00 .. 11,._ _____-+I 11"StOfr____ 311a12016 <1.o <1.0 <1.o <1.0 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 OuplicateTW4-70 <1.0 <1.0 <1.0 <1.0 48.3 <0.1
lp14,clh�0,,tr,.__---.!1 e-Oi.c12/2�0cc1,c6e::<"-1.,,0 _____ -+<::c1c,.O,._ __ f.'<1c-.0,__ ___ +:<-"1.,c_0 _____ +---------"'52�.�1 e=<,,_O.ce1 ______--jl ll1st0tr 3/15/2017 <1.0 <1.0 <1.0 <1.0 47.7 <0.1 DuplicateTW4-70 <1.0 <1.0 <1.0 <1.0 49.8 <0.1
112nd0tr 6/15/2017 <1.0 <1.0 <1.0 <1.0 51.5 <0.1 3rd Qtr 8/2/2017 <1.0 <1.0 <1.0 <1.0 51.8 <0.1 4th Qtr 10/10/2017 <1.0 <1.0 <2.0 <2.0 44.7 <0.1 DWMRC s lit sam le <1.0 <1.0 <2 0 <2.0 52 <0.1 11"'1'"'s'c1 a"'1
=, ==""=3,�1�412=0�1�8+-<'c1cc.o'---------t�<1'-'.o:c----+-<1ccoc----+<"-1.""o-----+------�530-.8=+-'<"-o.""1--------jl ll2nd0tr 6/13/2018 <1.0 <1.0 <1.0 <1.0 47.6 <0.1 DuplicateTW4-70 <1.0 <1.0 <1.0 <1.0 47.9 <0.1 3rd Ctr 8/30/2018 <1.0 <1.0 <1.0 <1.0 56 <0.1 4th0tr 12/12/2018 <1.0 <1.0 <1.0 <1.0 54.9 <0.1 1st0tr 3/16/2019 <1.0 <1.0 <1.0 <1.0 48.9 <0.1 2nd Ctr 6/1312019 <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 4thQtr 12/10/2019 <1.0 <1.0 <1.0 <1.0 54.4 <0.1 1st0tr 3/17/2020 <1.0 <1.0 <1.0 <1.0 50.0 <0.1 2nd Ctr 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 4thQtr 11 /4/2020 <1.0 <1.0 <1.0 <1.0 49.3 <0.1 3/17/2021 <1.0 <1.0 <1.0 <1.0 51.6 <0.1 6/16/2021 <1.0 <1.0 <1.0 <1.0 48.8 <0.1 9/15/2021 <1.0 <1.0 <1.0 <1.0 42.8 <0.1 r 12/812021 <1.0 <1.0 <1.0 <1.0 51.2 <0.1 ccTW,,4-:,:7cso�3/2=2=12=0�22,.j.��"":g'----------l•�+-�---1----1r:c'�:"�----+-:c;)cc:�-----+-----�:'=;"':�+-:cc�"c:�--------,1 TW4-70 <1.0 <1.0 <1.0 <1.0 39.2 <0.1 6/16/2022 <1.0 <1.0 <1.0 <1.0 42.2 l3rdQtr 9/1 4/2022 <1.0 <1.0 <1.0 <1.0 45.0 <0.1 4th Otr 12/7/2022 <1.0 <1.0 <1.0 <1.0 47.5 <0.1 1st0tr 3/29/2023 <1.0 <1.0 <1.0 <1.0 50.2 <0.1 2nd Qtr 6/20/2023 <1.0 <1.0 <1.0 <1.0 51.3 <0.1 3rd0tr 9/1312023 <1.0 <1.0 <1.0 <1.0 42.3 <0.1 (1) As of March 2012 bOth north and south wild life ponds no longer receiving water. NA:notanalyzed -----------Shaded indicates concentrations exceedi� GWQS. J : App(ox1mated value.
0.10
TABLE 1 (25 of 33)
Historic Summary Of Monitoring Well Analytical Results Up To The 3rd Quarter 2023 Chlorofonn Contamination Investigation
OUSA White Mesa Mill
TW4-24
(nitrate pumping well started
1/26/13) Sampling Event
2nd Qtr 6'2712007
3rdQtr 8/1512007 4th Qtr 10/10/2007
1stQlr 3/2812008
2ndQtr 6125/2008 JrdQtr 9/1012008
4th Otr 10/15/2008 11118/2008
1stOtr 314/2009 2ndQtr 6123/2009 3rd Ctr 9114/2009 4th Qtf 12/16/2009 l�:IClr 3/2512010 Ctr 6114/2010 Cir 8/2412010 th Ctr 10115/2010 stQtr 2/1612011 2nd Cir 611412011 3rd Ctr 811612011 4th Cir 11/15/2011 12/712011 1s1catr 12) 1/1612012 2nd Ctr --6/612012 3rd Ctr 8/30/2012 4th Ctr 10/312012 1s1Clrl3) -2/1112013 2nd Ctr 61512013 3rd Ctr 8/30/2013 Ath Qtr 1012912013
stOtr 1/27/2014 2nd Cir 511912014 3rd Ctr 811112014 4th Cir 10/21/2014 1st Ctr 319i2015 2nd Ctr 618/2015 i3rdQtr 8/3112015 10/19/2015 1st Ctr 3/912016 2nd Cir 5123/2016 3rd Cir 712512016 4th Ctr 10112/2016
1stOtr 31812017
2ndQtr 6113/2017 3rd Qtr 7126/2017
4th Ctr 1011112017
OWMRC&oli!samni. 311612018 611412018 8122/2018 1112812018
)WMRC aclit samole 1st Ctr 31812019
2nd Ctr 615/2019 3rd Qtr 91412019 4th Cir 12/10/2019 1stOtr 2/1912020 2nd Ctr 5/2712020 3rd Qtr 91412020
Carbon Tetrachloride Chlorofonn Chloromethane 15 µgll) 170 unll) 130 µgill
<1.0 2.6 <1.0
<1,0 2.2 <1.0
<1.0 1.5 <1.0
<1.0 1.5 <1.0
<1.0 1.4 <1.0
<1.0 2.9 <1.0 NA #NIA NA
<2.0 <2.0 <2.0
<1.0 1.4 <1.0
<1.0 1.5 <1.0
<1.0 1.4 <1.0
<1.0 1.2 <1.0
<1.0 1.3 <1.0
<1.0 1.7 <1.0
<1.0 1.8 <1.0
<1.0 1.4 <1.0
<1.0 1.8 <1.0
<1.0 1.1 <1.0
<1.0 1.7 <1.0
NA #NIA NA
<1.0 1.2 <1.0
<1.0 <1.0 <1.0
<1.0 <1:0 ____ <1.0------
<1.0 <1.0 <1.0
<1.0 1 <1.0
<1.0-------------1 <1.0 ______
<1.0 17,4 <1.0
<1.0 21.8 <1.0
<1.0 32.5 <1.0
1.18 78 5 <1.0
<1.0 62.7 <1.0
<1.0 76.3 <1.0
<1.0 25.B <1.0
<1.0 4!i:2 <1.0
<1.0 4.28 <1.0
<1.0 46.9 <1.0
<1.0 25.3 <1,0
<1.0 22.8 <1.0 <1.0 69.6 <1.0
<1.0 17.8 <1.0
<1.0 20.B <1.0
<1.0 18.3 <1.0
<1.0 17.2 <1.0 <1.0 17.8 <1.0
<1.0 16.0 <1,0
<0.38 36.0 <0.60
<1.0 24.9 <1,0
<1.0 49.2 <1.0
<1.0 35 <1.0
<1.0 21 <1.0
<5.0 60 <5.0 <1,0 28.1 <1.0
<1.0 28.8 <1.0
<1.0 31.1 <1.0
<1.0 43.3 <1.0
<1.0 61.7 <1.0
<1.0 49.4 <1.0
<1.0 63.B <1.0
4th Ctr 1012812020 <1.0 72.6 <1.0
1st Ctr 2/2312021 96 2 3.6
2nd Ctr 6/912021 <1.0 41.9 <1.0
3rd Qtr 8/2612021 <1.0 103 <1.0 4th Cir 12/112021 <1.0 112 <1.0
1stOtr 3/912022 <1.0 114 <1.0
2nd Qtr 61812022 <1.0 124 <1.0
3rdOtr 8/30/2022 <1.0 BB 9 <1.0 4th Ctr 11/30/2022 <1.0 79 5 <1.0
1stOtr 3(712023 <1.0 99 5 <1.0
2nd Ctr 6113/2023 <1.0 58.3 <1.0
3rdOtr 819/2023 <1.0 65.7 <1.0
(1) voes were resampled because laboratory missed holding 11me
(2) As of March 2012 both north .ind south wild life ponds no longer receiving water.
(3)Chlorofonn�wel5tarted 1126/13 _______ _
NA,.notanalyzed
Shaded 1nd1cates concentrations eKceeding GWQS.
J : ApproK1mated value
Parameter
(GWCS)
Methylene Chloride 15 µgll) <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
NA <1.0 <1.0
<1.0 ----<1,0 <1.0
<1.0 ------
<1.0 <1.0
<1.0 <1,0
<1.0
<1.0 <1.0
<1,0 <l.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1,0 <1.0 1.3 J <1.0 <1.0 <1,0 <1.0 <5.0
<1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0
<1.0 <1.0
Chloride Nitrate, Nitrate+ Nitrite No GWCS lmgll) I10mgll) 770 26.1 791 29 692 24.7 740 24 4
834 45 3 1.180 38 4 1,130 44.8
#NIA #NIA 1,010 30 5 759 30 4 618 30 7 1,080 28.3 33 1 639 30 587 31 522 31 1.100 31 1.110 35 967 34 608 35
#NIA #NIA 373 37
---------3551 ____________ 37 489 37
---------
405 ____________ 38 1,260 35 9 916 23 7 998 33 t.030 35 809 31 6 1,020 35 0 1,150 31 5 1,050 35 7
944 34 6 1,290 31 8
788 25 3 909 29.6 989 29 1 771 24 2 1,180 34 4 1,010 31 9 1,090 41.3 t.080 39 9 1.230 40 o 895 31 7 1.100 32 0 1,320 44 9 792 33 6 996 33 8 1.100 38 4 1,000 34 0 1,040 39 3 1,020 33 2 1,130 36.4 1,090 33 8 1,010 37 1 1,060 41 7 1,100 39 1 1,050 35.9 1,170 41 9 938 48 0 1,010 26 7 1,140 43 6 980 36.2 944 35 0 868 32 0 972 27 6 932 36 2 866 35.9 928 26 2
TABLE 1 (26 of 33)
Historic Summary Of Monitoring Well Analytical Results Up To The 3rd Quarter 2023
Chlorofonn Contamination Investigation
OUSA White Mesa MIU
TW4-25
(nitrate pumpmg wel started
1/26113) Sampling Event
2nd Qtr 6{27/2007
3rd Qtr 8/15/2007 4th Ctr 10/10/2007
1st0tr 3/28/2008
2nd Otr 6/25/2008
3rd Qtr 9/10/2008 4th Ctr 10/15/2008 11/18/2008
1stQtr 3/4/2009
2nd Otr 6/23/2009
3rd Otr 9/14/2009 4th Ctr 12/16/2009
1stQtr 3/23/2010
2nd Qtr 6/14/2010
3rd Otr 8/10/2010
4thQtr 10/15/2010
1stQtr 2/16/2011
2nd0tr 5/25/2011
3rd Qtr 8/16/2011 4th Ctr 11/15/2011 1sro,, 1,, 111612012 2nd Ctr ---5/31/2012
3rd Qtr 9/4/2012 4th Ctr 10/3/2012 1st Ctr (3) 2/11/2013
2ndQtr 6/5/2013
3rd Qtr 9/4/2013 4th Ctr 10/31/2013
1st0tr 1/27/2014
2nd Qtr 5/19/2014
3rd Qtr 8/11/2014
4th0tr 10/21/2014
1stQtr 3/9/2015
2nd Otr 6/8/2015
3rd Qtr 8/31/2015
4th0tr 10/19/2015
1stQtr 3/9/2016
2nd0tr 5/23/2016
3rd Otr 7/25/2016
4thQtr 10/12/2016
1st0tr 3/8/2017
2nd Qtr 6/13/2017
3rd Otr 7/26/2017
4th0tr 10/11/2017
1st0tr 3/12/2018
2nd0tr 6/14/2018
3rd Qtr 8/22/2018 4th Ctr 11/28/2018
1st0tr 3/8/2019
2nd Qtr 6/5/2019
3rd Otr 9/4/2019
4thQtr 12/10/2019
1stQtr 2/19/2020
2nd Qtr 5/27/2020
3rd Qtr 9/4/2020 4th Ctr 10/28/2020
1stQtr ii:23/2021
2nd Qtr 6/9/2021
3rd Otr 8/26/2021
4thQtr 12/1/2021
1st0tr 3/9/2022
2nd Otr 6/8/2022
3rd Qtr 8/30/2022 4th Ctr 11/30/2022
1stQtr 3(7/2023
2ndQtr 6/13/2023
3rdQtr 8/9/2023
Carbon Tetrachloride
15 µgill
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
NA <2.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0 ----
<1,0
<1.0
<1.0-----
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
Chlorofonn Chloromethane
170 µg/L) 130 µg/Ll
<1.0 <1.0
2.2 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
#N/A NA
<2.0 <2.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1,0
<1.0 <1.0
<1.0 <1.0
1.8 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1,0 <1.0
<TO ____ <1.0------
<1.0 <1.0
<1.0 <1.0
<TO ____ <TO ______
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1,0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0 1.15 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0 1.15 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 :::1.0
<1.0 <1.0
<1.0 1.34
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
<1.0 <1.0
(1) voes were resampled because laboratory missed holding hme
(2) As of March 2012 both north and south wild life ponds no longer receiving water.
j�Chloroform_pum9weNstarted 1/26113 _______ _ NA"" not analyzed
Shaded indicates concentratlOf'ls exceeding GWOS.
Parameter
(GWCS)
Methylene Chloride
15 ug/Ll
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
NA <2.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0 <1.0
<1.0 -----
<1.0
<1.0
<1.0 -----
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0 <1.0
<1.0
<1.0 <1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
Chloride Nitrate, Nitrate+ Nitrite No GWCS lmn/L) (10mg/L) 395 17.1 382 29 358 17 374 18 7
344 22.1 333 18.8 366 21 3 #NIA #NIA 3 15 3
328 15 3
328 3.3 371 14.2 296 14.4 306 16 250 14
312 15 315 15 321 16 276 16
294 16 304 16 ---------2871 ---16 334 17 _________ 338 ____________ 17 190 9.04 136 5.24 119 5.69 88.6 6.1 85.7 2.16
51.1 1.21 67 1.6
58.1 1.03
310 14 4 58.3 1.14 69.2 1.63 93.7 1.78 62.7 0.837 75.5 0.959 74.1 1.78
59.8 1.24
285 17 0 69.8 0.976 70.1 1.23
68.0 1.29 70.5 2.23 60.3 1.14 69.1 0.810
59.7 0.634 65 59 0.821 58.1 0.548 73.1 0.841
86.0 0.607 76.8 0.851 67.3 0.994 61.3 1.64 100 3.43
55.1 1.57 69.3 0.793 93.7 0.978 70.3 1.8
72.8 0.88 82.5 1.51 67.2 1.47
96.7 1.96 73.0 1.03 79.9 0.79
TABLE 1 (27 of 33) Historic Summary Of Monitoring Well Analytical Results Up To The 3rd Quarter 2023 Chloroform Contamination Investigation OUSA White Mesa Mill
TW4-26 Parameter Sampling Event IGWQS) Carbon Tetrachloride (5 "g/L) 2nd Ctr 6/14/2010 <1.0 3rd Ctr 8/24/2010 <1.0 4thQtr 10/15/2010 <1.0 1stQtr 2/16/2011 <1.0 2nd Qtr 5/26/2011 <1.0 3rdQtr 8/17/2011 <1.0 4thQtr 11/16/2011 NA <1.0 I 1.L______@'.? 12011 • "<1.0 lsHlTrT2l 111812012 2nd Otr -6/6/2012 3rdQtr 9/11/2012 4thQtr 10/3/2012 1st0tr 2/11/2013 2ndQtr 6/13/2013 3rd Otr 9/5/2013 4thQtr 11/7/2013 1st0tr 1/29/2014 2ndQtr 5/21/2014 3rd Qtr 8/11/2014 4th0tr 10/28/2014 1s!Qtr 3/12/2015 2nd0tr 6/10/2015 3rd Qtr 9/3/2015 41hQtr 10/28/2015 1s!Otr 3/16/2016 2nd Qtr 5/26/2016 3rd Qtr 8/3/2016 4th Qtr 10/20/2016 1s!Qtr 3/16/20-17 2nd Qtr 6/20/2017 3rd Qtr 8/3/2017 4th Qtr 10/11/2017 1st0tr 3/21/2018 2nd0tr 6/14/2018 13rd Qtr 9/6/2018 l4th0tr 12/13/2018 1stQtr 3/20/2019 12nd Otr 6/5/2019 3rd Qtr 9/12/2019 Mhn>, 12/18/2019 1st0tr 3/18/2020 2nd Qtr 6/12/2020 3rd Qtr 9/19/2020 4thQtr 11/11/2020 1s!Qtr 3/24/2021 2nd Qtr 6/17/2021 3rd Otr 9/23/2021 4th Qtr 12/9/2021
<1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 :Cio <1.0 <1.0 <1.0 �ro <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0
Chloroform Chloromethane
170 uo/Ll (30 "g/LI 13 <1.0 5.2 <1.0 5.4 <1.0 2 <1.0 2.9 <1.0 2.8 <1.0 #N/A NA 5.2 <1.0 7 <1.0 -----c.1 <1.0 ______ 4.9 <1.0 4.9 <1.0 4.9 <1.0 2.12 <1.0 2.81 <1.0 3.37 <1.0 1.43 <1.0 4.23 <1.0 1.3 <1.0 2.45 <1.0 2.37 <1.0 6.12 1.17 4.77 <1.0 3.45 <1.0 i:s <1.0 8.23 <1.0 4.42 <1.0 19.9 <1.0
,_ 46.1 <1.0 244 <1.0 419 <1.0 608 <1.0 1,050 <1.0 960 <1.0 916 <1.0 1.050 <1.0 963 <1.0 1,070 <1.0 877 <1.0 1.070 <1.0 1,090 <1.0 1.140 <1.0 1120 <1.0 1.160 <1.0 1.030 <1.0 1.020 <1.0 927 <1.0 993 <1.0
Methylene Chloride 15 ug/Ll <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 NA <1.0 <1.0 <1.0 ----
<1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <-1.0 <1.0 <1.0 <1.0 �ro <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 1s!Otr 3/24/2022 <1.0 952 2.4 <1.0 2nd0tr 6/22/2022 3rd Otr 9/15/2022 4th Qtr 12/9/2022 1st0tr 3/29/2023 2ndQtr 6/21/2023 3rdQtr 9/27/2023 TW4-27 1st Ut'JZL __ 1/18/2012 2nd Qtr 6/13/2012 3rd Qtr 9/4/2012 4th Qtr 10/3/2012 1stQtr 2/7/2013 2nd Qtr 6/13/2013 3rdQtr 8/30/2013 4thQtr 11/6/2013 1st0tr 1/23/2014 2nd Otr 5/21/2014 3rdQtr 8/13/2014 4thQtr 10/28/2014 1st0tr 3/11/2015 2nd Qtr 6/10/2015 3rdQtr 9/2/2015 4thQtr 10/28/2015 1st0tr 3/16/2016 2ndQtr 5/26/2016 3rdQtr 8/3/2016 4thQtr 10/20/2016 1st0tr 3/15/2017 2nd Otr 6/15/2017 3rd Qtr 8/2/2017 4thQtr 10/10/2017 1stQtr 3/14/2018 2nd0tr 6/13/2018 3rdQtr 8/30/2018 4thQtr 12/12/2018 1s!Otr 3/16/2019 2nd0tr 6/13/2019 3rd Qtr 9/11/2019 4thQtr 12/14/2019 1stQtr 3/18/2020 2nd0tr 6/11/2020 3rd Qtr 9/18/2020 4th Qtr 11/4/2020 1stQtr 3/18/2021 2nd Otr 6/17/2021 3rd0tr 9/15/2021 4thQtr 12/8/2021 1st0tr 3/23/2022 2nd Qtr 6/16/2022 3rd0tr 9/14/2022 4thQtr 12/8/2022 1s!Otr 3/29/2023 2nd0tr 6/21/2023 3rd Otr 9/14/2023
<1.0 <1.0 <1.0 <1.0 <1.0 <1.0
<1.0 _________ <1.0 <l.O <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <f·o <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0
790 <1.0 930 <1.0 890 <1.0 703 <1.0 659 <1.0 709 <1.0
9 <1.0 <TO ____ <""i_Q ______
<1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 1.3 <1.0 1.6 <1.0 2.1i" <1.0 3.16 <1.0 2.78 <1.0 3.8 <1.0 4.33 <1.0 5.65 <1.0 6.05 <1.0 5.91 <1.0 6.95 <1.0 5.95 <1.0 7.35 <1.0 7.7 <1.0 6.54 <1.0 8.24 <1.0 7.58 <1.0 7.97 <1.0 8.04 <1.0 7.92 <1.0 5.62 <1.0 7.8 <1.0 4.66 <1.0 4.26 <1.0 3.81 <1.0 4.08 <1.0 3.3 <1.0 3.1 <1.0 4.3 <1.0 2.3 <1.0 2.0 <1.0 2.5 <1.0 2.9 <1.0
(1) voes were re sampled because laboratory missed holdmg time
(2) As of March 2012 both north and ,outh wild life ponds no \Onger receiving water.
NA•notanalyzed
Shaded mcllcates concentrations exceeding GWQS
<1.0 <1.0 <1.0 <1.0 <1.0 <1.0
<1.0 <1.0 --
<1.0 <1.0 ·:era<1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <·1.0 <1.0 <1.0
Chloride No GWQS (mg/L) 33 17 22 30 15 19 26 #N/A 17 ---------,9 19 19 16.6 14.5 17.6 15.9 16.9 15.4 15 14.6 14.4 14.4 14 13.3 13.7 15.2 13.9 14.2 16.2 19 25.8 27.3 35.5 33.5 38.9 33.4 32.9 35.8 32.0 38.3 36.:i 35.1 34.8 36.3 38.9 34 36.5 34.9 33.0 34 36.7 32.7 34.5 33.5 34.0
11 ---------17 21 18 18_8-20.3 19 21.8 31.8 20.6 23 24.4 26.2 26.8 26.8 26.2 28 21.2 27.1 29.4 28.3 27.9 29.5 26.3 30.3 28.3 31.4 28.2 26.2 28.6 25.3 27.4 27.6 28.0 26.2 26.8 27.5 25.8 21.7 26.4 22.7 22.3 23.2 16.2 22.8 25.7 26.3
Nitrate, Nrtrate + Nitrite 110 mo/Ll 7.9 9.0 9.6 10.0 10.0 11 0 10.0 #N/A 11.0 ------,2 0 9.0 12.0 12.5 13 6 11 7 15.9 142 12.5 10.8 12.3 14.4 11 3 14.2 13.9 16.9 13.9 17.9 15.0 15.8 15.2 15.2 10.0 12.2 13.2 13 5 11 8 12.2 12.6 10.9 10.3 11.9 11.1 10.5 11 9 11 3 14 2 12.1 8.15 10.9 9.9 10.3 10.4 10 5 10 0 10.2
24 0 41.0 37.0 36.0 31.2 29 .4 27 2 29.8 31 3 31.1 27.0 28.2 26.5 24.0 20 .9 23.5 25 0 28 7 21 8 19.3 22 2 23 8 20.0 21.5 19.5 22.0 18 1 20 8 21 5 22.3 21 2 22 0 23 6 21 5 25.2 16.7 23 0 23.8 21 1 24.9 21 3 20 0 16.9 18.1 20.9 16.9 15.8
TW4-28
Sampling Event
TABLE 1 (28 ol 33)
Historic Summary Of Monitoring Well Analytical Results Up To The 3rd Quarter 2023
Chloroform Contamination Investigation
DUSA White Mesa Mill
Parameter IGWQSl
Carbon Tetrachloride Chloroform Chloromethane Methylene Chloride Chloride
(5 uo/L) 170 uo/Ll 130 un/Ll (5 pg/L) No GWQS (mall)
2nd Ctr 6/19/2013
3rd Ctr 8/29/2013 4th Ctr 11/6/2013
1st0tr 1/22/2014
2nd Qtr 5/21/2014
3rd Ctr 8/13/2014
4th Ctr 10/23/2014
1st Ctr 3/1112ois
2nd Otr 6/10/2015
3rd Qtr 9/2/2015 4th Ctr 10/21/2015
1st Ctr 3Tisi2016
DuplieateTW4-65 !2nd Ctr 5/25/2016
3rd Qtr 7/27/2016
Duplicate TW4-65 j4th Qtr 10/19/2016
n,,......,,.teTW4-65
[is1a1, 3/14/2017
OuplicateTW4-65
12nd0tr 6/14/2017
3rd Qtr 7/27/2017 4th Ctr 10/10/2017
1st0tr 3/14/2018
2ndQtr 6/12/2018
DuplicateTW4-65
3rd Qtr 8/29/2018 4th Ctr 11/30/2018
1stQtr 3/16/2019
2nd Qtr 6/13/2019
3rd Qtr 9/11/2019
4thQtr 12/12/2019
1st0tr 3/17/2020
2nd0tr 6/10/2020
3rd Qtr 9/17/2020 4th Ctr 11/4/2020
1st0tr 3/17/2021
2ndQtr 6/15/2021
3rd0tr 9/15/2021 4th Ctr 12/7/2021
1s1Qtr 3/15/2022
2nd0tr 6/15/2022
3rd Otr 9/13/2022
4thQtr 12/7/2022
1st Ctr 3/22/2023
OuplicateTW4-65
2nd0tr 6/15/2023
3rd Otr 9/13/2023
TW4-29
2nd Otr 6/19/2013
2nd Otr 7/11/2013
3rd Qtr 9/26/2013
4th0tr 11/13/2013
1st Ctr 2/5/2014
2ndQtr 5/22/2014
3rd Qtr 8/27/2014 4th Ctr 10/29/2014
1st0tr 3112/2015
2nd0tr 6/11/2015
3rd Qtr 9/3/2015
4thQtr 10/29/2015
1st Ctr 3Ti7i2016
2nd0tr 6/8/2016
3rd Qtr 8/3/2016 4thQtr 10/26/2016
1stQtr 3116/2017
2nd Otr 6/4/2017
3rdQtr 8/4/2017
4th0tr 10/11/2017
1!i atr 3114/2018
2nd Qtr 6/14/2018
3rd Otr 8/29/2018
4th Otr 12/13/2018
1st0tr 3/20/2019
2nd Qtr 6/13/2019
3rdQtr 9/12/2019 4th Ctr 12/18/2019
1stQtr 3118/2020
2nd Qtr 6/12/2020
3rd0tr 9/19/2020
4th Otr 11/11/2020
OWMRC &nlit •A-..la
,�Ctr 3/24/2021
2nd Qtr 6/17/2021
3rd0tr 9/23/2021
4th0tr 12/9/2021
DuDlic.ite TW4-75
1st Ctr 3/23/2022
2nd Otr 6/22/2022
3rd Qtr 9/23/2022
Duplicate TW4-75
4thQtr 12/9/2022
1stQtr 3r.?9/2023
2nd Qtr 6/21/2023
3rd Qtr 9/27/2023
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0 :;,_o <1.0 -�;·:a
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1,0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0 �'-i�o <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 242 <1.0
<1.0 262 <1.0
<1.0 246 <1.0
<1.0 260 <1.0
<1.0 258 -;;·fa
<1.0 262 <1.0
<1.0 242 <1.0
<1.0 290 <1.0
<1.0 299 <1.0
<1.0 329 <1.0
<1.0 276 <1.0
<1.0 631 <1.0
<1.0 335 <1:0
<1.0 366 <1.0
<1.0 401 <1.0
<1.0 392 <1.0
<1.0 446 <1.0
<1.0 420 <1.0
<1.0 466 <1.0
<1.0 431 <1.0
<1.0 533 <1.0
<1.0 474 <1.0
<1.0 454 <1.0
<1.0 521 <1.0
<·1.0 507 <1.0
<1.0 537 <1.0
<1.0 549 <1.0
<1.0 630 <1.0
<1.0 652 <1.0
<1.0 686 <1.0
<1.0 621 <1.0
<1.0 671 <1.0 <10 670 <20
<1.0 577 <1.0
<1.0 543 <1.0
<1.0 602 <1.0
<1.0 625 <1.0
<1.0 636 <1.0
<1.0 624 <1.0
<1.0 398 <1.0
<1.0 591 <1.0
<1.0 591 <1.0
<1.0 588 <1.0
<1.0 467 <1.0
<1.0 490 <1.0
<1.0 457 <1.0
H • Sample was analyzed beyond holdll'lg times and may not be accureate concen1rat10n
Shaded mdicates concentrations exceeding GWQS
<1.0 44.6
<1.0 45.3
<1.0 45.3
<1.0 47.8
<1.0 45.7
<1.0 50
<1.0 52.1
<1.0 52.2
<1.0 56.4
<1.0 61.4
<l.O 52.7
<1.0 5{ii
<1.0 61.4
<1.0 67.1
<1.0 70.1
<1.0 70.9
<1.0 70.9
<1.0 73.7
<1.0 64.2
<1.0 66.4
<1.0 68.6
<1.0 67.1
<1.0 57.4
<1.0 65.0
<1.0 55.7
<1.0 56.7
<1.0 63.8
<1.0 52.4
<1.0 51.7
<1.0 51.8
<1.0 49.0
<1.0 50.0
<1.0 52.1
<1.0 49.8
<1.0 47.4
<1.0 49.0
<1.0 51.8
<1.0 48.5
<1.0 40.7 <1.0 47.8
<1.0 38.8
<1.0 52.3
<1.0 58.5
<1.0 52.0
<1.0 46.1
<1.0 49.4
<1.0 51.3
<1.0 51.1
<1.0 44.8
<1.0 37.7
<1.0 41.4
<1.0 42.5
<1.0 14.9
<1.0 38.2
<1.0 41
<1.0 41
<1.0 40.5
<1.0 42.5
<1.0 47.3
<1.0 39.8
<1.0 4"0'.s
<1.0 42.9
<1.0 40.6
<1.0 44.2
<1.0 41.5
<1.0 42
<1.0 42.9
<1.0 37.7
<1.0 43.1
<1.0 40.1
<1,0 45.9
<1.0 40.9
<1.0 3�9
<1.0 39.4
<1.0 38
<1.0 44.8
<1.0 41
<1.0 42.2
<1.0 39.9
<1.0 40.8 <20 42
<1.0 44.3
<1.0 40
<1.0 40.1
<1.0 38.7
<1.0 40
<1.0 39.1
<1.0 41.5
<1.0 41.8
<1.0 42.0
<1.0 41.3
<1.0 41.3
<1.0 42.2
<1.0 41.1
Nitrate, Nitrate+ Nitrite 110 mg/L) 14.9 17.3 16 2 16.9 16.5 14.2 16.5
19.0 19.0
178 18.7 ------34.0 32.6 29.0 31 3 35.6 25.5 25.4 24 4 27.9 26 0 24.8 24.8 17 2
19.0 18.7 16.0 17.7 17 .2 15.0 10.2 9.48 9.87 9.55 8.36 7.76 8.68 9.09 8.08 7.60 7.80
15.0 16.2 16.6 11 9 11.1 11.9 11.5 4.60 3.52 4.18 4.11 4.63 3.52 3.40 3.64 4.14 2.95 2.19 2.74 2.92 2.51
2.44 2.40 2.24 2.26 2.35 2.45 2.44 2.67 2.52 2.50 2.67 2.56 2.55 2.58 3.10 3.18 2.90 3.27 0.75 H 3.09 3.59 3.29 2.39 1.91 3.10 2.9 2.80 2.76 2.69 2.74 2.65 2.82
TW4-30 Sampling Event
TABLE 1 (29 of 33) Historic Summary Of Monitoring Well Analytical Results Up To The 3rd Quarter 2023 Chloroform Contamination Investigation
Carbon Tetrachloride (5 µg/L)
DUSA White Mesa Mill
Parameter IGWQSl Chloroform Chloromethane Methylene Chloride Chloride
170 µg/L) (30 µQ/L) (5 µg/L) No GWQS (mg/L)
Nitrate, Nitrate+ Nrtrite
(10mc/LI 2nd Q t r 6/19/201 3 <1.0 <1.0 <1 .0 <1.0 36 0.95 3rd Q tr 9/26/2013 <1.0 <1.0 <1.0 <1 .0 36.3 0.952 l,4;-,lh�Q:ccl�r ___ 1
c.;
1'=/1
,c'
3/2=0"-1
c-'c
3+<
'-c
1
-'c.0;--____ --j..C<-'-'1.,,_0 __ -+<-'-'1-'c.o;--___ +-<1".oc---____ -l--------"-35,c,-9e+---------"1 .24
1st Ctr 1/23/2014 <1.0 <1.0 <1.0 <1 .0 3 6.9 1.36 2nd Q tr 5/22/2014 <1.0 <1.0 <1.0 <1 .0 31.9 1 .44 3 rdOtr 8/23/2014 <1.0 <1.0 <1.0 <1.0 3 8 1.5
1e�=��1 g"":�;--�1'e�=i=��7�-s-)c,,;+:�]-'S:��--------1 <1.q •• ··1 .es :�":�-�---+--:��:��-------+-----����:;'+--------�1�:�'";' 2nd Q t r 6/11/201 5 <1.0 2.25 <1.0 <1.0 40.3 1.75
3 rd Q tr 9/3/2015 <1.0 3.27 <1.0 <1 .0 44 .2 1.75
11c�;-e:'-'g:cc:�;--�1cc�fcc1=��=�"']cc:+:'--c]"":�;------_,----'=';J�·+·:'c]"":�,.__ ___ +:-]"':�c--------+-------�"-�""::,+---------'-1."'·�:"l1 2nd Qtr 5126/2016 <1.0 7.38 <1.0 <1.0 40.2 2.04 3 rd Otr 8/31201 6 <1.0 6.79 <1.0 <1.0 38.6 2.32
4thOtr 10120/2016 <1.0 8.69 <1.0 <1.0 41 .3 2.51
1stOtr 3/1512017 <1.0 13.6 <1.0 <1.0 37.7 2.70 2ndQtr 6/15/2017 <1 .0 15.2 <1.0 <1.0 37.8 2.95 3 rd Ot r 8/3/201 7 <1.0 15.7 <1.0 <1.0 39.8 3.11
, .. ����'--g�:�;--�1=���:=��=����� ... :�i�:g�----_,--�:=��:: ... :�i�:g ---·---�·� "�+g�------1-------3�4"'4�'-l--------=-;:�:8"'3 ' 2ndOtr 6/1 3/201 8 <1 .0 16.9 <1.0 <1.0 3 7.4 3.93
3 rd Q tr 8/30/201 8 <1 .0 19.8 <1.0 <1.0 44.1 3.79 4th Q tr 12112/201 8 <1 .0 23.9 <1.0 <1.0 3 5.5 3.70
1stOtr 3/15/2019 <1.0 25.3 <1 .0 <1.0 35.9 4.08 2nd Q tr 6/13 /2019 <1 .0 31.5 <1.0 <1.0 27.2 4.13 3rd Q t r 9/11/2019 <1.0 34.8 <1 .0 <1.0 34.5 3.79
4th Q tr 12/1 8/201 9 <1.0 44.9 <1.0 <1.0 39.1 3.62
1stOtr 3/1 7/2020 <1.0 53.1 <1 .0 <1.0 3 7.5 3.85 2nd Q tr 6/12/2020 <1.0 65.4 <1 .0 <1.0 38.6 3 .69
3 rd Q tr 9/1 8/2020 <1.0 1_ 67.7 <1.0 <1.0 35 3.49
4th Q tr 1 1/1 112020 <1.0 1_82.8 <1 .0 <1.0 3 7.1 3 .64 DWMRC solit sam le <10 66 <20 <20 39 <0.5 H
1stQtr 3/1 7/2021 <1.0 74.8 <1 .0 <1.0 "--·-37_5 3.54 2nd Ot r 6/1 7/2021 <1.0 78.7 <1.0 <1 .0 3 8.3 4.19 3rd Q tr 9 /22/2021 <1.0 78.2 <1.0 <1 .0 23.5 2.60
4th Q t r 12/8/2021 <1.0 81.2 <1.0 <1.0 3 7.9 3.14 1st Q tr 3/23/2022 <1.0 73.6 <1 .0 <1 .0 35.1 3 .0 2nd Q tr 6/22/2022 <1.0 70.8 <1.0 <1.0 41.3 2.8 3rd Qtr 9/1412022 <1.0 68.8 <1.0 <1 .0 3 0.5 2.61 ll'4"'thccO'-"t,__r ----c'121=9='12=0�2"'2+-<'-'1 "'.o _____ _, __ _,60"".s,+-<1'-'.oc---___ +<-"1 ."'o _____ +-____ �35_5 ,_ _____ _,2,,,.6'-'-'7' 1st Q tr 3/29/2023 <1.0 45.5 <1 .0 <1.0 3"is":Ef 2.84 2nd Q tr 6121/2023 <1.0 47.0 <1.0 <1 .0 36.8 3 .0 3rd Otr 9 /14/2023 <1.0 47.8 <1.0 <1.0 36.7 3 .34
TW4-31 2ndQtr 6/19 /2013 <1.0 <1.0 <1.0 <1.0 28.4 1.3
3 rd Qtr 9/5/201 3 <1 .0 <1.0 <1.0 <1.0 29.4 1.1 4th Q tr 11/7/2013 <1.0 <1.0 <1.0 <1.0 28 1.33 1stOtr 1/23/2014 <1.0 <1.0 <1.0 <1 .0 28.5 1.32 2ndOt r 5/21/2014 <1 .0 <1 .0 <1.0 <1.0 26.3 1.22 3rd Q t r 8/13/2014 <1 .0 <1 .0 <1.0 <1.0 30 1 .1 4th Q tr 10/28/201 4 <1 .0 <1.0 <1.0 <1.0 3 7.1 1.84 1st Q tr 3/11/201 5 <1 .0 <1 .0 <1.0 <1.0 30.6 1.33 2nd Ctr 6/1 0/2015 <1 .0 <1 .0 <1 .0 <1.0 31.1 1.19 3rd Q tr 9/2/201 5 <1 .0 <1 .0 <1.0 <1.0 30.4 0.9 16
'"i=:'--'g"":��-�1""�f,,,fig�! :�:g :�:g :�:g :�:g ��:� 0 t�! 2nd Q tr 5/25/2016 <1 .0 <1.0 <1 .0 <1.0 3 2.5 1 .36 3rd Q t r 7/28/2016 <1.0 <1 .0 <1 .0 <1.0 30.6 1.41
4thQtr 10/20/2016 <1.0 <1.0 <1.0 <1.0 3 4 1.14
1st Ct r 3/1 5/2017 <1.0 <1 .0 <1.0 <1.0 31 .3 1.19 2nd Ct r 6/1 5/2017 <1 .0 <1.0 <1.0 <1.0 33 .4 1 .21
3 rd Q tr 8/2/2017 <1.0 <1.0 <1 .0 <1 .0 3 3 1 .11
4th Ctr 10/1 0/2017 <1.0 <1 .0 <1 .0 <1.0 30.9 1.04 1stQtr 3/14/201 8 <1 .0 <1.0 <1.0 <1.0 3 8.8 0.916 2nd Ot r 6/12/201 8 <1.0 <1.0 <1.0 <1.0 34.4 0.948
3 rd Q tr 8/29/201 8 <1.0 <1.0 <1 .0 <1.0 40.3 0.71 0
''"i��h�1g�:�;--�1��}�g�� :�:g :�:g -��":g'------+:-'-]"":�'----------1-------"'35""j;'-1-------"�"':;-"�:"ll 2nd Q tr 6/1312019 <1.0 <1.0 <1 .0 <1 .0 36.9 0.71 3 3 rd Ctr 9/11/2019 <1.0 <1.0 <1.0 <1 .0 35.8 0.61
4th Ct r 12/14/2019 <1.0 <1.0 <1 .0 <1 .0 40.6 0.5 8 "1"'"'s""1a='1'--,----'-'3'""11 1/2020 <1.0 <1.0 <1.0 <1.0 38.2 0.572 2nd Ot r 6/12/2020 <1.0 <1.0 <1.0 <1 .0 36.7 0.569 3rd Q tr 9/17/2020 <1.0 <1.0 <1.0 <1.0 36.5 0.51
4th Ct r 1 1/4/2020 _<1�.o�-----+-<�1=_0 __ _,_<1�.o�-----+-<�1 -=0-----+------�36.4+--------"-0 .c,_50"-'l1
1stQtr 3/17/2021 <1.0 <1.0 <1.0 <1 .0 4Qj. 0.5 01 2nd Ot r 6/1612021 <1.0 <1.0 <1.0 <1 .0 37.9 0.451 3rd Q tr 9 /1 5/2021 <1 .0 <1.0 <1.0 <1.0 31.2 0.46
4th Qtr 12/8/2021 <1.0 ___ <.!.-.9,_ __ .._<�1�.0�---<1.0�-----+------�40�.3"-+------�0�.3�3"'9
1st Ctr 3/16/2022 <1.0 <1.0 <1.0 -<"f() 34 .3 0.4 2nd Q tr 6/16/2022 <1.0 <1.0 <1.0 <1.0 35.5 0.41 3rd Q tr 9/13/2022 <1.0 <1.0 <1.0 <1.0 40 0.396 lf���h�1a=O:�;----,�-'S2;'.s.
3�=g�,,;+:-;-c:ge----------,f--:��:-s-�----t�t-'c:g'------+:-'-']"':�c---------l-------;'.";"'::,f------�0"'�3�!10
11 2ndOtr 6/15/2023 <1.0 <1.0 <1.0 <1.0 43 .1 0.444 3rd Qtr 9/13 /2023 <1.0 <1.0 <1 .0 <1.0 42.4 0.340 Shaded indicates concentrat10ns eKceed1ng GWOS H = Sample was analyzed beyond holding times and may not be accureate concentration.
1W4-32
Sampling Event
TABLE 1 (30 of 33)
Historic Summary Of Monitoring Well Analytical Results Up To The 3rd Quarter 2023
Chloroform Contamination Investigation
DUSA White Mesa Mill
Parameter
IGWQSI
Carbon Tetrachloride Chloroform Chloromethane Methylene Chloride Chloride
(5 µg/L) 170 un/L) (30 µg/L) (5 µg/L) No GWQS (mg/L)
4thQtr 11/14/2013 <1.0 <1.0 <1.0 <1.0 52.1
1st0tr 1/2212014 <1.0 <1.0 <1.0 <1.0 54.5
2nd Qtr 5/21/2014 <1.0 <1.0 <1.0 <1.0 54.9
3rd0tr 8/13/2014 <1.0 <1.0 <1.0 <1.0 64
4th Qtr 10/23/2014 <1.0 <1.0 <1.0 <1.0 62.6
1st Ctr 3/11/2015 <1.0 <1.0 <1.0 <1.0 64.2
Duplicate TW4-65 <1.0 <1.0 <1.0 <1.0 65.9
2nd Otr 6/10/2015 <1.0 <1.0 <1.0 <1.0 62.7
3rd Ctr 91212015 <1.0 <1.0 <1.0 <1.0 59.6
4thQtr 10/21/2015 <1.0 <1.0 <1.0 <1.0 55.1
1stQtr 3/15/2016 <1.0 <1.0 <1.0 <1.0 64.2
2nd Qtr 5/25/2016 <1.0 <1.0 <1.0 <1.0 71.8
3rd Qtr 7128/2016 � <1.0 <1.0 <1.0 64.4
10/19/2016 <1.0 <1.0 <1.0 <1.0 66
1st Ctr 3/17/2017 <1.0 <1.0 <1.0 <1.0 62.8
2nd Ctr 6/15/2017 <1.0 <1.0 <1.0 <1.0 53.5
3rd Ctr 81212017 <1.0 <1.0 <1.0 <1.0 65.8
4thQtr 10/10/2017 <1.0 <1.0 <1.0 <1.0 65.8
1st0tr 3/14/2018 <1.0 <1.0 <1.0 <1.0 6sX
2nd Otr 6/1212018 <1.0 <1.0 <1.0 <1.0 59.2
3rd0tr 8/29/2018 <1.0 <1.0 <1.0 <1.0 68.1
4thQtr 11/30/2018 <1.0 <1.0 <1.0 <1.0 57.5
1st0tr 3/16/2019 <1.0 <1.0 <1.0 <1.0 57.5
2nd Qtr 9/11/2019 <1.0 <1.0 <1.0 <1.0 60.1
3rd0tr 9/11/2019 <1.0 <1.0 <1.0 <1.0 55.0
4thQtr 12/14/2019 <1.0 <1.0 <1.0 <1.0 64.7
1stQtr 3/17/2020 <1.0 <1.0 <1.0 59.7
2nd Otr 6/10/2020 <1.0 <1.0 <1.0 <1.0 57.0
3rdQtr 9/17/2020 <1.0 <1.0 <1.0 <1.0 50.8
4th0tr 11/4/2020 <1.0 <1.0 <1.0 <1.0 53.7
1st0tr 3/17/2021 <1.0 <1.0 <1.0 <1.0 60.5
2nd Otr 6/15/2021 <1.0 <1.0 <1.0 <1.0 40.4
3rd0tr 9/15/2021 <1.0 <1.0 <1.0 <1.0 46.1
4th0tr 12/7/2021 <1.0 <1.0 <1.0 <1.0 55.0
1st0tr 3/16/2022 <1.0 <1.0 <1.0 "<1.0 48.0
2nd Qtr 6/15/2022 <1.0 <1.0 <1.0 <1.0 49.4
3rd Otr 9/13/2022 <1.0 <1.0 <1.0 <1.0 51.8
DuplicateTW4-65 <1.0 <1.0 <1.0 <1.0 53.6
4thQtr 12/7/2022 <1.0 �L9 _________ <1.0 <1.0 48.4
1stQtr 3/23/2023 <1.0 -<1.0 <-1.0 43.6
2nd Ctr 6/15/2023 <1.0 <1.0 <1.0 <1.0 49.3
3rd Qtr 9/13/2023 <1.0 <1.0 <1.0 <1.0 52.6
1W4-33
4th0tr 11/14/2013 <1.0 126 <1.0 <1.0 47.2
1stQtr 1/30/2014 <1.0 124 <1.0 <1.0 43.5
2nd0tr 5/2212014 <1.0 121 <1.0 <1.0 46.8
3rd Qtr 8/2712014 <1.0 104 <1.0 <1.0 43
4th0tr 10/29/2014 <1.0 124 <1.0 <1.0 44.2
1stQtr 3/1212015 <1.0 134 <1.0 <1.0 44.2
2nd0tr 6/11/2015 <1.0 127 <1.0 <1.0 46.6
3rd Otr 9/3/2015 <1.0 123 <1.0 <1.0 53.3
4thQtr 10/29/2015 <1.0 129 <1.0 <1.0 44.5
1st Ctr 3/17/2016 <1·�0 122 <1.0 <1.0 46.2
2ndQtr 6/8/2016 <1.0 96.1 <1.0 <1.0 49.7
3rd Otr 8/4/2016 <1.0 121 <1.0 <1.0 48.5
4th0tr 10/26/2016 <1.0 109 <1.0 <1.0 52.4
3/1712017 <1.0 90.7 <1.0 49.0
2nd Otr 6/20/2017 <1.0 103 <1.0 <1.0 49.2
3rd Qtr 8/3/2017 <1.0 127 <1.0 <1.0 46.9
4thQtr 10/11/2017 <1.0 97.1 <1.0 <1.0 42.5
1stQtr 3/15/2018 <1�0 128 <1.0 <1.0 49.2
2nd0tr 6/13/2018 <1.0 87.8 <1.0 <1.0 44.0
3rd Qtr 9/5/2018 <1.0 113 <1.0 <1.0 50.0
4th Qtr 12/13/2018 <1.0 141 <1.0 <1.0 43.2
1stQtr 3/20/2019 <1.0 86.2 <1.0 <1.0 47.2
2nd Qtr 6/19/2019 <1.0 121 <1.0 <1.0 43.4
3rd Qtr 9/12/2019 <1.0 101 <1.0 <1.0 41.1
4th Qtr 12/18/2019 <1.0 117 <1.0 <1.0 48.8
1st Qtr 3/18/2020 <1.0 93.7 <1.0 <1.0 45.3
2nd Qtr 6/10/2020 <1.0 90.1 <1.0 <1.0 48.9
3rdQtr 9/18/2020 <1.0 84.9 <1.0 <1.0 51.0
4th0tr 11/11/2020 <1.0 80.6 <1.0 <1.0 51.5
DWMRC solitsam le <10 68 <20 <20 54
3/18/2021 <1.0 64.9 <1.0 <1.0 55.6
2nd Qtr 6/17/2021 <1.0 63.9 <1.0 <1.0 54.7
3rd0tr 9/2212021 <1.0 60.2 <1.0 <1.0 42.5
4th0tr 12/8/2021 <1.0 68.9 <1.0 <1.0 53.8
1st0tr 3/23/2022 <1.0 53.1 <1.0 <1.0 51.4
2nd Otr 6/2212022 <1.0 58.7 <1.0 <1.0 56.7
3rd Qtr 9/14/2022 <1.0 53.9 <1.0 <1.0 42.2
4thQtr 12/9/2022 <1.0 50.5 <1.0 <1.0 45.1
1st0tr 3/29/2023 <1.0 47.7 <1.0 <1.0 52.6
2ndQtr 6/21/2023 <1.0 51.8 <1.0 <1.0 52.9
3rd Otr 9/14/2023 <1.0 51.3 <1.0 <1.0 52.0
Shaded md1cates concentrations exceeding GWQS
H " Sample was analyzed beyond holding times and may not be accureale concentration.
Nitrate, Nitrate+ Nitrite
(10mg/L)
4.26
5.11
5.63
4.2
2.14
2.46
2.25
1.21
5.09
1.19
4.48
3.16
3.44
2.87
2.82
2.37
2.47
2.47
2.94
2.51
2.56
2.50
2.15
2.18
1.84
1.89
1.97
2.19
1.58
1.74
1.80
2.31
1.57
1.34
1.80
1.20
1.59 1.81 1.68
1.53
1.77 1.63
1.82
2.56
1.63
1.50
2.22
1.91
1.62
1.64
1.92
2.13
2.06
2.32
2.36
2.11
2.34
2.04
2.09
1.94
2.13
1.82
2.01
2.00
2.16
1.61
1.86
2.44
3.26
3.58
3.71
0.12H
4.62
6.25
4.33
4.65
3.80
3.70
3.90
3.52
3.93
4.24
4.19
------------------------------------------------------------------------TABLE 1 (31 of 33) Historic Summary Of Monitoring Well Analytical Results Up To The 3rd Quarter 2023 Chloroform Contamination Investigation
DUSA White Mesa Mill
I Sampling Even t Parameter IGWQSI Carbon Tetrachloride (5 µg/L) Chloroform Chloromethane Methylene Chloride Chloride (70 µg/L) (30 µg/L) (5 µgll) No GWQS (mn/LI Nitrate, Nitrate+ Nitrite 110m•IL) ��'}g! 1 lJ;�ga :; g :; g :H :::i ��! ; �; [2nd Qtr 5122/2014 <1.0 <1.0 <1.0 <1.0 17.9 1.69 [3rd Qtr 8/1312014 <1.0 <1.0 <1.0 <1.0 18 1.10 [4thQtr 1012 9/2014 <1.0 <1.0 <1.0 <1.0 17.8 1 .1 6 li'si'atr 3111 12015 <1.0 <1 .0 <1.0 <1.0 17.7 1.21 2nd Qtr 6/1112015 <1.0 <1.0 <1.0 <1.0 17 .4 0.868 3rd Qtr 9/3/201 5 <1 .0 <1.0 <1.0 <1.0 15.1 0.458 •:g: 1��!�g)�'f-:'-')�g'-----------J--':-")"'-g---+:'-')�g'-------+:-:)"'g,;------+------'-')�"•�'-!-------'g"'•�"'�"l�I:2nd Qtr 5/25/201 6 <1 .0 <1.0 <1.0 <1.0 18 0.605 3rdQtr 8/312016 <1.0 <1.0 <1.0 <1.0 17.2 0.726 4thQtr 1012012016 <1 .0 <1.0 <1 .0 <1.0 19 0.612 1st atr 311512011 <1.0 <1.0 <1.0 <1 .0 18.o ···o.674 2nd Qtr 6/1 512017 <1.0 <1 .0 <1.0 <1.0 15.7 0.727 3rdQtr 81212017 <1.0 <1.0 <1.0 <1.0 19.8 0.733 4th Qtr 10/1012017 <1.0 <1.0 <1.0 <1 .0 18.5 0.774 ��ftiftlV/4:"5 311412018 :: g :1g ::l :Jg ��•� g�� 2nd Qtr 6/1312018 <1.0 <1.0 <1.0 <1.0 1 9.5 0.877 3rd Qtr 812912018 <1.0 <1.0 <1.0 <1 .0 23.8 0.736 f��-z:� 1���g�� :�:g ···'-':��:�g---,:+g.---:tg ��:: g:::� 2ndQtr 6/13/201 9<1 .0 <1 .0 <1.0 <1.0 20.1 0.994 3rd Qtr 9/1112019 <1.0 <1.0 <1.0 <1.0 17 .8 0.934 �:g: 1f);�g�� ::g ::"'.g'--------J-':"':""g----1':"-)"'g -····'-------�i�/ci�b 2ndQtr 6/1012020 <1 .0 <1.0 <1.0 <1.0 20.9 1 .240 3rd Qtr 9/1 712020 <1.0 <1.0 <1 .0 <1.0 19.0 0.978 4thQtr 1 1/412020 <1 .0 <1.0 <1 .0 <1.0 18.7 1.04 isiciii ···37ffi:20:ii' <Lil • <1.0 <1.0 <1.0 19.3 T:iiii 2nd Qtr 6/1612021 <1.0 <1.0 <1 .0 <1.0 17.8 1 .08 3rd Qtr. 9/1512021 <1.0 <1.0 <1.0 <1 .0 15.0 1.1 4th Qtr 12/812021 <1.0 <1.0 <1.0 <1.0 1 9.6 1 .02 1st Qtr 311612022 <1.0 ••-<1.0 <{o· • <i-:ii.. •• • 17.:i 1.0 2nd Qtr 6/1612022 <1.0 <1.0 <1.0 <1.0 1 9.5 1.0 3rdQtr 9/1412022 <1.0 1.2 <1 .0 <1 .0 18.8 0.788 4th Qtr 12/812022 <1.0 <1.0 <1.0 <1.0 17.0 1 .16 i'sfc:itr 312912023 <i:o 1 .2 <1 .0 <1.ci io.7 1.1 2ndQtr 612012023 <1.0 1 .2 <1.0 <1.0 21.2 1 .09 3rd Qtr 9/14/2023 <1.0 <1.0 <1.0 <1.0 20.6 1.27 TW4-35 3rdQtr 812712014 <1.0 <1.0 <1.0 <1.0 34 0.2 4thQtr 101281201 4 <1 .0 <1.0 <1.0 <_1.0 _____ +-------"3"-4·c!.J1 0.351 1stQtr 3/11/201 5 <1 .0 <1_0-<1jf <1.0 34.9 •• 0.436 2ndQtr 6110/2015 <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 1c;;c:;;g:c,��r --�1"'�lcc1='!�=g�)cc�+-:'c)-"'g '----------+�:);.cg,;---t-Jg.�---4�J'.g�-----"------�}�'.� g;�� 2ndQtr 5/26/2016 <1.0 <1.0 <1 .0 <1.0 35.4 0.631 Qtr 8/312016 <1.0 <1.0 <1 .0 <1 .0 34.8 0.723 g:; 1�i��g1� :ig�------t-:)"'•g---.. :--e).csg-. ta �H··· g��� d Qtr 6/1512017 <1.0 <1.0 <1.0 <1 .0 34.8 0.699 Qtr 81212017 <1.0 <1.0 <1.0 <1.0 36.3 0.670 1 �H�i�¼ :fg :: g :; � HJ �; � ····· H�i6/1312018 <1.0 <1.0 <1.0 <1.0 33 .7 0.662 8/30/2018 <1.0 <1.0 <1.0 <1.0 39.3 0,527
1 2/1212018 <1 .0 <1.0 <1.0 <1 .0 43.0 0.559 1s !Qtr 3/161201 9 <1 .0 <f.o -·--·· ·;;1 :0 .. •• <1 .0 33:s 0.574 2ndQtr 6/131201 9 <1.0 <1.0 <1.0 <1.0 35.5 0.670 3rdQtr 9/11 /2019 <1.0 <1 .0 <1.0 <1.0 31 .7 0.525 ���g: 1f);�g�� :: g :1�g---+-:)�g� :1 g ��: ----·· ....... g��:2nd Qtr 6/11/2020 <1 .0 <1 .0 <1.0 <1.0 34.0 0.699 3rdQtr 9/1712020 <1.0 <1 .0 <1.0 <1.0 32.2 0.760 t��-g�--��";1'-'I;"'�g��t-:"-)"':g'---------+·1ti -:}�·-···· ............... -:t-i··· ��·:!-�·-··-g:��� 2ndQtr 6/1 6/2021 <1.0 <1.0 <1.0 <1.0 34.1 1.01 l3rdQtr 9/1512021 <1.0 <1.0 <1.0 <1.0 27.5 1 .2 thQtr 1 2/812021 <1.0 <1 .0 <1 .0 1<1.0 34.3 1 .23 stQtr 3122/2022 <1.0 <1.0 <1 .0 1<1.0 2fjj'" 1.3 l2ndQtr 6/1612022 <1.0 <1.0 <1.0 <1.0 31.2 1.6 [3rdQtr 9/1412022 <1.0 <1.0 <1 .0 <1 .0 34.4 1 .61 thQtr 12/712022 <1.0 <1.0 <1.0 1<1 .0 27.4 1.79 s1atr 31291202:i <1.0 • <1.0 <1 .0 1<1.0 ·33.8 • i'.1• [2nd Qtr 6/2012023 <1.0 <1.0 <1 .0 <1 .0 29.8 1 .91 Qtr 9/1312023 <1.0 1.4 <1.0 <1 .0 32.4 2.0 Qtr
Qtr Qtr 2ndQtr 3rd Qtr 4thQtr
8/27/2014 <1.0 <1.o <1.0 rd_,.n, .................................. --+----65 <0.1 ·fo/2312014 <1.0 <1.0 <1.0 l,1 n ___ _,,6"'7-"-3 1------<0.1 •••••• ............... 3iffi20f5 <11>· <r·o <1.0 <1 .0 s1.2 <0.1
TW4-70
·eifOl201s <1.o <1.0 <1.o <1.0 69.3 <0.1 9/3/2015 <1.0 <1.0 <1.0 <1 .0 76.4 <0.1
1 ���·�g�: :�:g �+i :�:g ;l�i!!-------+-----�:;,,:��------.:::�g:o-1)1 S/26/2016 <1.o <1.0 <1.o <1.0 72.3 <0.1 i/28/2frfEf<1-:-i5 <1 .o <1.o <1.o ............ 69.4 <0.1 10/20/2th6.<i'i:f.... <1.0 <1.0 <1.o ...... ·73 .8 <0.1 <1 .0 <1 .0 <1.0� __ ___,<._,1"'.0'------+-----72 <0.1 311512011 <1.0 <1.0 ·:c·-.,·�o ·::1.0 .... ·66".2 • ·<·0:1 6115/2017 <1 .0 <1.o <1.0 <1.o ·11.3 <0.1 8121201 1 <1 .0 <1 .o <1.0 <1.o ·69.6 <0.1 1i�!�_ ... J!111��rn;Jl .·.}!t ···•·········�1t··-··················.1!l �i -----9:1fi thQtr .... 1t�igl!L1.o ...................................... .. <.1.°0' ... <i·o ............ <1.0 65.8 0.1 23 s1atr 311512019 <1.0 ;;i:o • •• <i:o -- • <1.0-• es ·o :He 2'1CfQtr 6i1'3120{9 ·<rif'.. <1.o .......... <r·o <1.0 11 .5 <0.1 ••••••••• 1�U�gJf::� ••• 1:: � 1:1 ···· 1:; g ��� :g l 311112020 <1 .0 1<1 .0 .. ..1.� .. 1.,.. 1<1.0 sifi <0.1 6/111'2020 <1 .0 <1 .0 1:<.t <1.0 67.o <0.1 9/17/2020 <1 .0 <1 .0 1<1 <1.0 66.0 • <0.1 tr · 11/4/2020 <1.0 <1 .0 1<1 <1.0 61:,9 (.... <0.1 1st atr 311112021 ·<-.,-,·a <1 .o 1.� .. t <1.0 12.5 .. <0.1 2nd Qtr 6/16/2021 <(0.... <1 .0 1<1 <1.0 68.7 . _<0.1 3rd Ctr.. 9/1512021 c(fi <1:ci .J<1.0 <1.0 63.1 <0.1 4th atf 1 21812021 ·<fO <1 .o r:cr·o" <1.o 69.9 <0.1 F1c'scctQtr�--�3/16.f2022 .<fi:I "<1 .0 <1.0 <1.0 61.2 0.1 2nCi"Qtr... 6/15/2022 <1.0 <1 .0 <fo <1.0 68.8 <0.1 3r(i'Otr • 911312022 <1.0 <1 .0 <1.0 <1.0 69.3 .<.ci:·1 ,..,41 -'ctsht""a a""ttrr __ -=12.lli.2022 ·<fO...... <1 .0 .... .. . :11 .•. 00....... .. ........... <1.0 59. 7 "·--o.·.·.·.:.·.i .. o.O} fri.. <1.0 :· ... :: .. :::.:::::·:::::::: .. ·�rr..<1.0 eo.1 2n CiQtr'. 6/1 1 .0 <1 .0 • <1.o <1.0 68.9 <0.1 3rdQtr ... n ............................ <L°O .. <'f�o'.... <1.0 67.3 ·oj·4
Shaded mdicates concentrations exceeding GWOS.
TW4-37
(chloroform pumping well 619/15)
Sampling Event
2nd Otr 6/8/2015
3rd Qtr 9/3/2015 4thQtr 10/19/2015
1st0tr 3/9/2016 2nd Otr 5/23/2016 3rd Otr 7/25/2016 4thQtr 10/12/2016 1stQtr 3/8/2017 2nd Qtr 6/15/2017 3rdQtr 7/26/2017 4thQtr 10/11/2017 1stQtr 3/12/2018 2nd Otr 6/8/2018 3rdQtr 8/22/2018 4th Otr 11/28/2018 1st0tr 3/8/2019 2nd Qtr 6/5/2019 3rd0tr 9/4/2019 4th Qtr 12/10/2019 1st Ctr 2/19/2020 2nd Qtr 5/27/2020
3rd0tr 9/4/2020 4thQtr 10/28/2020
1stQtr 2/23/2021 2nd Qtr 6/9/2021 3rdQtr 8/24/2021 4th Qtr 12/1/2021 1stQtr 3/!1/2022 2nd Qtr 6/8/2022 3rd Qtr 8/30/2022 4th Qtr 11/30/2022 1stQtr 3{7/2023
2nd Otr 6/20/2023 3rd Qtr 8/!1/2023
TW4-38
4th Qtr 11/10/2016 1st0tr 3/15/2017 2nd Qtr 6/15/2017 3rd Qtr 8/2/2017 4th Qtr 10/10/2017
1st0tr 3/14/2018 2ndQtr 6/13/2018 3rd Qtr 8/30/2018 4thQtr 12/12/2018
1st0tr 3/16/2019 2ndQtr 6/13/2019
DuplicateTW4-70 3rd Otr 9/11/2019 4thQtr 12/14/2019 1st0tr 3/17/2020 2ndQtr 6/11/2020
3rd Otr 9/18/2020 4th0tr 11/4/2020 1Sfatr 3/18/2021 2nd Qtr 6/16/2021
Duplicate TW4-70 3rd Qtr 9/15/2021 4thQtr 12/8/2021 1stQtr 3/22/2022 2ndQtr 6/16/2022
3rd Otr 9/14/2022 4thQtr 12/7/2022 1st0tr 3/29/2023 2ndQtr 6/20/2023 9/13/2023 �TW4-70
(11/2016) Qtr 11/11/2016 ���Qtr 3/8/2017 Qtr 6/15/2017 13rd Qtr 7/26/2017 l4thQtr 10/10/2017
l1st0tr 3/12/2018 12nd Qtr 6/8/2018 13rd at, 8/22/2018
th Qtr 11/28/2018 stQtr 3/8/2019 l2ndQtr 6/5/2019 13rd Qtr 9/4/2019 14th Qtr 12/10/2019 11s!Qtr 2/19/2020 l2ndQtr 5/27/2020 13rd Qtr 9/18/2020 4thQtr 10/28/2020
��Qtr 2/23/2021 Qtr 6/9/2021 Qtr 8/24/2021
th Otr 12/1/2021 stQtr 3/9/2022 12nd Qtr 6/8/2022 3rdQtr 8/30/2022 th Qtr 11/30/2022
stQtr 3(7/2023 2nd Qtr 6/13/2023
TABLE 1 (32 of 33)
Historic Summary Of Monitoring Well Analytical Results Up To The 3rd Quarter 2023
Chloroform Contamination Investigation
DUSA White Mesa Mill
Parameter (GWQS)
Carbon Tetrachloride Chloroform Chloromethane Methylene Chloride Chloride (5 uo/L) (70 UQ/L) (30 ug/L) (5 ug/L) No GWQS (mg/L) 18.2 30.200 15.7 1.94 345 16.6 19,100 13.7 1.04 374 12.5 19.500 9.38 1.17 399 15.8 17,500 3.5-7 1.34 332 14.4 16.200 3.57 1.17 389 16.7 15,900 <1.0 <1.0 294 16.3 16.400 <1.0 304 15.4 18,000 3.57 1.34 305 16.2 15,800 <1.0 <1.0 281 15.1 15,000 <1.0 <1.0 277 12.6 15,500 2.47 <1.0 255 12.8 12,900 1:14 <1.0 263 10.6 14.400 <1.0 <1.0 275 12.1 14,100 6.2 <1.0 387 11.3 15.200 19.8 <1.0 264 ... 13.8 13,300 1.24 -�1.0 209 14.6 16.200 <1.0 <1.0 250 10.7 11,900 1.9 <1.0 228 8.81 13,100 3.12 <1.0 220 8.53 12.000 12.3 <1.0 236
11.8 11.700 1.44 <1.00 321 9.62 13,800 <1.0 <1.0 273 6.52 10,300 29.4 <1.0 254
<1.0 ••• ···-9.380 <1.0 <1.0 242 8.46 13,000 1.98 <1.00 176 7.65 10.200 <1.0 <1.0 220 11.5 14,800 5.05 410
12.2 13.700 <1.0 <1.0 414 8.2 46,800 12 <1.0 276 5.4 11,600 2.4 <1.0 243 5.7 9,640 <1.0 <1.0 578
<1.0 8,010 <1.0 <1.0 209 1.6 8,160 5.7 <1.0 329 3.2 9 620 <1.0 <1.0 252
<1.0 <1.0 <1.0 <1.0 40
<1.0 <1.0 <1.0 <1.0 35.7
<1.0 <1.0 <1.0 <1.0 36.2
<1.0 <1.0 <1.0 <1.0 36.9
<1.0 <1.0 <1.0 <1.0 31.3
<1.0 <1.0 <1.0 <1.0 36.5
<1.0 <1.0 <1.0 <1.0 33.1
<1.0 <1.0 <1.0 <1.0 39.2
<1.0 <1.0 <1.0 <1.0 35.0
<1.0 <1.0 <1.0 <1.0 33.5
<1.0 <1.0 <1.0 <1.0 33.7
<1.0 <1.0 <1.0 <1.0 35.3
<1.0 <1.0 <1.0 <1.0 31.6
<1.0 <1.0 <1.0 <1.0 36
<1.0 <1.0 <1.0 33.4
<1.0 <1.0 <1.0 <1.0 34.9
<1.0 <1.0 <1.0 <1.0 34.7
<1.0 <1.0 <1.0 <1.0 35.1
<1.0 <1.0 <1.0 <1.0 31:2
<1.0 <1.0 <1.0 <1.0 37.7
<1.0 <1.0 <1.0 <1.0 35.7
<1.0 <1.0 <1.0 <1.0 32.1
<1.0 <1.0 <1.0 <1.0 35.8
<1.0 <1.0 <1.0 <1.0 32.7
<1.0 <1.0 <1.0 <1.0 37.3
<1.0 <1.0 <1.0 <1.0 32.9
<1.0 <1.0 <1.0 <1.0 36.4
<1.0 <1.0 <1.0 <1.0 37.2
<1.0 <1.0 <1.0 <1.0 36.3
<1.0 <1.0 <1.0 <1.0 40.6
<1.0 <1.0 <1.0 <1.0 41.1
<1.0 2.800 <1.0 <1.0 68.9 8.15 -6.460 <1.0 1.35 130 8.2 5,560 <1.0 1.31 120
14.4 10,000 <1.0 1.5 132
<1.0 552 <1.0 <1.0 73.5 3.1 2.870 <1.0 <1.0 118 7.94 7,160 <1.0 <1.0 107 12.5 8,180 2.33 <1.0 110 6.08 6,520 2.33 <1.0 123 1.2 885 <1.0 <1.0 49 11.6 8,640 <1.0 <1.0 114 5.71 4.240 <1.0 <1.0 48.2 1.!_4_ 1.650 <1.0 <1.0 74.7
<1.0 812 <1.0 <1.0 76.5 7.56 5,870 <1.0 <1.0 88.511 8.18 5,960 <1.0 <1.0 63.2
<1.0 648 1.19 <1.0 83.2
<1.0 2.970 <1.0 <1.0 53.0[ 7.56 2.490 <1.0 <1.0 123
<1.0 858 <1.0 <1.0 78.;I <1.0 776 <1.0 <1.0 82.4
<1.0 724 <1.0 <1.0 75.2[ 1.4 982 <1.0 <1.0 76.8
<1.0 843 <1.0 <1.0 85.2 1.2 1.720 <1.0 <1.0 80.6
<1.0 1,850 <1.0 <1.0 38:Y 1.8 3,330 3.1 <1.0 75.4
<1.0 3 440 <1.0 <1.0 95.5
Shaded indicates concentrations exceeding GWQS.
Nitrate, Nitrate+ Nitrite (10 mg/L) 35.2 32.4 34.6 28.4 27.9 33 4 26.1 32.3 31.2 30.5 30.6 30.0 28.6 25.3 27.3 30 .1 31.2 25.8 25.5 28.3 28.3 29.5 28.7 26.9 26.6 25.8 31.3 29.8 28.0 26.6 30.9 19.1 35.9 25.1 11.2 10.6 10.8 10.1 10.3 9.34 9.48 7.77 8.48 8.96 8.53 9.52 7.61 7.51 8.11 9.00 7.35 7.72 8.24 9.59 9.05 8.04 8.02 7.7 7.9 7.57 8.9 8.78 8.2 8.14 8.18
20.7 6.44 6.25 7.74 2.65 3.33 4.84 6.05 6.39 2.08 8.45 1.75 0.95 0.792 5.01 2.69 7.03 2.12 12.0 2.70 2.33 2.9 9.0 3.72 7.86 1.37 8.0 5.01
TW4-40
(chlo,oform pumping weU 5/2019)
TABLE 1 (33 of 33) Historic Summary Of Monitoring Well Analytical Results Up To The 3rd Quarter 2023 Chloroform Contamination Investigation DUSA White Mesa Mill
Parameter
(GWQS)
Carbon Tetrachloride Chloroform Chloromethane Chloride
(5 ug/L) ug/L) (30 pg/L) (5 pg/L) No GWQS (mg/L)
1st Ctr 3/21/2018 2nd Qtr 6/13/2018 3rd Ctr 915/2018 4th Qtr 12/12/2018
Dupli�t� TW4-75 l2\fsfCi\r 312012019 2nd Qtr ----615/2019 3rd Ctr 914/2019 4th Ou 12/10/2019 1st Ctr 2/19/2020 2nd Qtr 5/27/2020 3rd Ctr 9/4/2020 4th Ctr 10/28/2020 1st Ctr 2/23/2021 2nd Ctr 6/9/2021 3rd Ctr 8/24/2021 14th Qtr 12/1/2021 1stQtr 3/9/2022 12nd Qtr 6/8/2022 13rd Qtr 8/30/2022 14th Ou 11/30/2022 1st0tr 3(7/2023
l2nd0tr 6/13/2023
;
Qtr 8/9/2023
4-41 (ch!orolorm pumping well
5/2018) Qtr 5/8/2018 Qtr 8/22/2018 thOtr 11/28/2018 stQtr 3/8/2019 ndOtr 6/5/2019 rdQtr 9/4/2019 thQtr 12/10/2019 1stQtr 2/19/2020 2nd Qtr 5/27/2020 3rd Qtr 9/4/2020 4thQtr 10/28/2020 1stQtr 2/23/2021 2nd Qtr 6/9/2021 3rd Qtr 8/24/2021 thQtr 12/1/2021 stOtr 3/912022 2nd Qtr 6/8/2022 3rdQtr 8/30/2022 4thQtr 11/30/2022 1stQtr 3(7/2023 2nd Qtr 6/13/2023
6/19/2019 9/11/2019 12/10/2019
TW4-75 Qtr 2117/2020 d Qtr 6/10/2020 Qtr 9/17/2020 Qtr 11/4/2020 Qtr 3/17/2021 d Qtr 6/15/2021 Qtr 9/15/2021 th Qtr 12/9/2021 st Qtr 3/15/2022
DuplicateTW4-65 2nd Qtr 6/15/2022 3rd0tr 9/13/2022 Qtr 1217/2022 Qtr 3/22/2023 d Qtr 6/15/2023
,I1eateTW4-65 Qtr 9/13/2023
TW4-43 Qtr 12/9/2021 Qtr 3/17/2022 Qtr 6/16/2022 Qtr 9/13/2022 Qtr 1217/2022 Qtr 3/23/2023 dQtr 6115/2023 Qtr 9113/2023
<1.0 <1.0 <1.0 <1.0 <1.0
<1.0-----
<1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0
<1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0
<1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0
<1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0
<1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0
Shaded 1ndtcates concentra!IOOS exceeding GWQS
(21 Chlofoform.pu}11!!!9)Ydi started 1n Mat,_2019 ______ .
248 <1.0 <1.0 131 <1.0 <1.0 116 <1.0 <1.0 118 <1.0 <1.0 119 <1.0 <1.0 <1.0 <1.0 ----153 <1.0 ----
380 <1.0 <1.0 314 <1.0 <1.0 364 <1.0 <1.0 367 <1.0 <1.0 333 <1.0 <1.0 264 <1.0 <1.0 436 3.51 <1.0 343 <1.0 <1.0 301 1.32 <1.0 286 <1.0 <1.0 238 �1.0 <1.0 323 <1.0 <1.0 302 <1.0 <1.0 298 <1.0 <1.0 259 <1.0 <1.0 220 1.3 <1.0 282 <1.0 <1.0
1.400 <1.0 <1.0 1.390 <1.0 <1.0 1.320 <1.0 <1.0 1.220 <1.0 <1.0 1.320 <1.0 <1.0 1.190 <1.0 <1.0 1.410 <1.0 <1.0 1,200 <1.0 <1.0 1.220 <1.0 <1.0 1.110 <1.0 <1.0 1.020 <1.0 <1.0 1,170 <1.0 <1.0 1.130 <1.0 <1.0 1.100 <1.0 <1.0 1.030 <1.0 <1.0 1.030 ·�1.0 <1,0 1.010 <1.0 <1.0 1.060 <1.0 <1.0 1.050 <1.0 <1.0 985 <1.0 <1.0 1.040 1.8 <1.0 1 050 <1.0 <1.0
<1.0 <1.0 <1.0 <1.0 <1.0 <1.0
<1.0 <1.0 <1,0 <1.0 <1.0 <1.0
<1.0 <1.0 <1.0 <1.0 <1.0 <1.0
<1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 �-1.0 <1.0
<1.0 <1.0 <1.0 <1.0 <1.0 <1.0
<1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1.0 <1,0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1.0 <1.0 <1.0
<1,0 <1.0 <1.0 <1.0 <1.0 <1.0
35.7 31.6 37.6 29.9 32.3 30.9 35.6 35.9 36.7 38.5 36.5 34.2 34.6 36.0 27.5 31.8 38.4 36.8 36.6 39.3 44.8 23.5 37.6 39.7
42.8 45.5 41.4 39.1 38.1 39.4 42.1 44.4 41.7 40.2 39.7 40.6 39.5 37.1 43.2 37.3 41.1 41.9 38.0 34.4 40.3 41.0
23.3 20.6 22.6 22.6 23.2 23.1 23.5 22.4 24.2 24.6 16.6 24.2 21.5 17.7 24.0 15.6 36.4 21.2 20.9 22.7 20.4
40.6 39.2 41.8 43.1 40.7 28 41.7 35.1
Nitrate, Nitrate+ Nitrite (10 mg/L) 3.08 3.33 3.22 3.54 3.18 3.18 3.55 3.39 2.89 2.98 2.91 2.88 2.58 2.43 3.77 1.50 2.60 2.5 1.90 2.22 2.24 1.28 2.04 1.88
6.54 6.13 6.02 6.71 6.00 6.22 6.11 6.12 6.78 6.69 6.25 6.41 7.45 3.77 6.72 6.2 6.0 5.92 6.0 4.3 6.27 5.59
2.57 2.75 2.82 2.95 2.88 3.23 3.65 2.77 3.15 3.57 3.26 2.02 2.5 2.6 3.3 3.3 2.02 2.8 3.14 3.2 3.33
0.118 0.4 0.24 0.383 0.383 0.384 0.43 0.410
Parameter GWQS
Chloride none
Nitrate + Nitrite (as N) 10 mg/L
'Chloroform 70 µg/L
Carbon tetrachloride 5 l,l�q/.b__ Chloromethane 30 µg/L
Methvlene Chloride 5 11n/L
nc = not calculated
Table 2
Summary of EFR QA/QC Samples
3rd Quarter 2023
Duplicate Samples of Wells
Duplicate of TW4-12 Duplicate of TW4-5
TW4-12 TW4-65 RPO
50.3 52.5 -4.3--·· 4.02 4.66 -14.7
<1.0 <1.0 nc
<1.0 <1.0 nc
<1.0 <1.0 nc ----·-<1.0 <1.0 nc
TW4-5
50.5
8.830
9.1
<1.0
<1.0
<1.0
TW4-70
53.2
8-t
8.8 -·�· <1.0
<1.0
<1.0
RPO
-� .
-5.2
8.6
3.4
nc
nc
nc
High lighted exceeding PRD (Relitve % difference) of 20%
Duplicate of MW-32
MW-32 TW4-75 RPO
37.5 37.6 -0.3
<1.0 <1.0 nc
<1.0 <1.0 nc
<1.0 <1.0 _I}_(: <1.0 <1.0 nc
<1.0 <1.0 nc
Well ID MW4 MW-26 TW4-1
'1>chloroform (ug/L) 1,020 2,610 891
Chloroform (g/L) 1.02E-03 2.61E-03 8.91E-04
Chloroform (lbs/L) 2.25E-06 5.77E-06 1.97E-06
Chloroform (lbs/qal) 8.53E-06 2.18E-05 7.45E-06
Total gallons pumped 95,944.3 26,841.5 8,419.4
lbs of chloroform removed 0.8 0.6 0.06
Gallons of chloroform removed 0.07 0.05 0.01
total lbs of chloroform removed 7.2
total aallons of chloroform removed 0.6
Tabel3
Chloroform Mass Removal Calculations for the 3rd Qurater 2023
EFR White Mesa Mill, Bland, Utah
TW4-2 TW4-4 TW4-11 TW4-19 TW4-21 TW4-22
867 1,020 2,630 198 49.7 1,890
8.67E-04 1.02E-03 2.63E-03 1.98E-04 4.97E-05 1.89E-03
1.92E-06 2.25E-06 5.81 E-06 4.37E-07 1.10E-07 4.18E-06
7.25E-06 8.53E-06 2.20E-05 1.66E-06 4.16E-07 1.58E-05
11,513.8 8,580.2 1,277.7 104,098.2 89,276.6 23,422.7
0.08 0.1 0.03 0.17 0.0 0.37
0.01 0.01 0.00 0.01 0.00 0.03
1) Assuming that the chloroform concentration result for the quarter monitoring event is the average chloroform concentration for the entire quarter.
Chloroform Pumping Wells
ru:ate Pumpin"g,c:W=e:::11s:.-. ______ _.
TW4-24 TW4-25 TW4-37 TW4-39 TW4-40 TW4-41
65.7 0 9,620 3,440 282 1,050
6.57E-05 O.OOE+OO 9.62E-03 3.44E-03 2.82E-04 1.05E-03
1.45E-07 O.OOE+OO 2.13E-05 7.60E-06 6.23E-07 2.32E-06
5.49E-07 0.00E+OO 8.05E-05 2.88E-05 2.36E-06 8.78E-06
57,213.1 117,564.3 46,548.5 34,299.4 43,550.1 10,780.6
0.031 0.00 3.7 1.0 0.10 0.1
0.003 0.00 0.30 0.08 0.01 0.01