2017-06-26_HYDROLOGY - M1980244

• Permit No: M1980244
• IBM Index Class Name: Hydrology
• Doc Date: 6/26/2017
• Doc Name: Demonstration of Compliance with WQCC Regulation No 41
• From: Newmont
• To: DRMS
• Email Name: TC1
• Media Type: D
• Archive: No

4. Data
Results of chemical analyses of water samples taken from the wells were extracted from the CC&V
environmental monitoring database and reviewed as spreadsheets. Table 2 provides a general overview
of the data.
Table 2: Overview of groundwater monitoring well data.
Drainage No. of Earliest Analyses General Comments
Wells Sample Pre 1/31/94
Arequa 2 12/7/93 2 each well 17 and 33%of samples below detection for manganese
and Zn
Grassy 4 7/16/98 Zinc always below detection,5-81%of samples below
detection for Mn
Vindicator 2 6/30/04 31 and 100%of samples below detection for Zn
Wilson Ck. 2 3/15/92 6,WCMW 3-134 2 and 47%of samples below detection for manganese,
2,WCMW 6-234 81 and 97%for Zn
Squaw 4 9/25/14 3 wells are essentially always dry, limited samples from
SGMW 6B-60
Poverty 2 1 /31/00 1 Dry except for 2000 and 2001
Tables 3 and 4 present summary statistics for each sampling location; Table 3 has the data for sulfate
and field pH, Table 4 has the data for manganese and zinc. The data shown in Tables 3 and 4 generally
indicate significant variability in the analytical results for any given sampling location, with the exception of
the data for Vindicator Valley. Figure 3 shows the sulfate concentration data for the Arequa Gulch
monitoring wells as an example of sample-to-sample variability.
Table 3: Summary statistics for sulfate and pH data used in the present analysis (S.D. is standard
deviation, Max. is maximum, Min. is minimum, n is the number of samples with results above the
detection limit, N.D. is not detected).
Sulfate m /L Field pH
Drainage Well Geomean S.D. Max Min n Geomean S.D. Max Min n
Arequa CRMW 3A-35 745 184 1260 424 120 6.25 0.20 6.88 5.25 123
CRMW 3B-63 765 141 1130 200 140 6.73 0.16 7.09 6.13 139
Geomean 755 260 6.49 262
Grassy GVMW 8A-250 68 8 107 51 87 7.26 0.59 10.8 6.87 92
GVMW 8B-50 96 44 246 53 75 6.84 0.41 8.84 6.17 88
GVMW 22A-70 49 22 1 161 39 1 29 1 7.84 0.24 8.29 1 7.02 39
GVMW 22B-30 70 17 104 27 28 6.71 0.21 7.17 6.19 28
Geomean 69 219 7.15 247
Vindicator VIN 2A-270 705 26 760 662 13 7.25 0.13 7.50 7.05 58
VIN 213-140 718 55 792 548 26 7.20 0.11 7.56 6.94 100
Geomean 711 39 7.22 158
Wilson WCMW 3-134 21 5 44 12 127 7.69 0.15 8.14 6.84 131
WCMW 6-234 56 8 1 80 39 1 92 7.03 0.13 7.52 1 6.70 90
Geomean 34 219 7.35 221
Squaw SGMW 613-60 971 80 1140 873 10 6.47 0.20 6.83 6.12 14
Poverty PGMW 1A-200 521 6 529 513 6 6.56 1.50 10.28 4.52 13
PGMW 1B-55 285 57 401 226 9 3.68 0.27 4.36 3.41 14
Geomean 362 1 1 1 4.87