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Final Technical Report, 2014 Monitoring Well Rehabilitation Program Bowie Mine 22
<br />3.4 Replacement Well BRL- IP- 14 -67 -D -BLW
<br />No water quality data have been collected at well BRL- IP- 00 -67 -D -BLW since 2006, due to
<br />compromised casing issues. Bowie abandoned well BRL- IP- 00 -67 -D -BLW on September 3,
<br />2014 and drilled replacement well BRL- IP- 14 -67 -D -BLW, as part of the 2014 well rehabilitation
<br />program and described previously in this report. The replacement well is drilled very close to
<br />the abandoned well and has similar screened intervals, so it should have similar water quality.
<br />The static water level was 295.28 ft btoc on October 20, 2014.
<br />Water samples were successfully collected from the replacement well on October 20, 2014.
<br />Samples were collected according to EPA protocols and sent to Accutest Laboratories in
<br />Wheatridge, CO for analysis. The field and laboratory water quality data (Bowie, 2014b), are
<br />summarized in Table 4 and copies of the lab results are presented in Appendix B.
<br />The baseline data presented in Table 4 are for the abandoned well (Bowie, 2014b). The field pH
<br />in the replacement well was 7.85 s.u. and the lab pH was 7.92 s.u. on October 20, 2014. The pH
<br />values are similar to the abandoned well's minimum baseline pH value of 7.8 s.u. (field) and
<br />7.73 s.u. (lab) and much improved of the maximum baseline pH value of 11.62 (field) and 11.58
<br />s.u. (lab).
<br />The field and lab conductivity values for the replacement well were 5,510 and 3,930 µmhos /cm,
<br />respectively, on October 20, 2014, similar to the range of baseline values from the abandoned
<br />well.
<br />Baseline temperatures in the abandoned well ranged from 11.1 to 27.9 °C (Bowie, 2014b). The
<br />temperature of the water in the replacement well was 19.6 °C on October 20, 2014, within the
<br />range of baseline temperatures at the abandoned well.
<br />The well's laboratory water quality results for the samples collected on October 20, 2014 also
<br />included the following: hardness total 55.1 mg/L, ammonia (1.1 mg/L), bicarbonate (3,510
<br />mg/L), calcium (15.6 mg/L), chloride (271 mg/L), iron dissolved (0.0358 mg/L), iron total
<br />(0.595 mg/L), magnesium dissolved (3.92 mg/L), manganese dissolved (0.0899 mg/L),
<br />manganese total (0.104 mg/L), phosphorus total (0.16 mg/L), sodium dissolved (1,350 mg/L),
<br />sulfate (10.4 mg/L), total dissolved solids (1,760 mg/L), and zinc (0.0826 mg/L) .
<br />Concentrations of arsenic, cadmium, carbonate, mercury, nitrate, nitrite and selenium were
<br />below lab detection limits. These values are similar to values found in the abandoned well and
<br />other wells in the area (Bowie, 2014b).
<br />The water in the replacement well is sodium bicarbonate type, similar to the abandoned well
<br />(Figure 2).
<br />November 2014 HydroGeo, Inc.
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