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Final Technical Report, 2014 Monitoring Well Rehabilitation Program Bowie Mine 20 <br />3.3 Well CWI -DH -60 <br />The goals for a successful rehabilitation of well CWI -DH -60 included resolving the issues of the <br />mud cake buildup on the inside of the casing and screen that prevented the collection of samples <br />for laboratory analysis. No water quality data have been collected at this well prior to the <br />initiation of the 2014 well rehabilitation program (Bowie, 2014b). The static water level was <br />1,073 ft btoc on September 15, 2010 (dry) and 947.35 ft btoc after rehabilitation on October 20, <br />2014. This indicates that the well did not have time to recharge after cementing activities in <br />September 2010. <br />Water samples were successfully collected from this well in October 2014, subsequent to the <br />completion of the well rehabilitation program. Samples were collected according to EPA <br />protocols and sent to Accutest Laboratories in Wheatridge, CO for analysis. The field and <br />laboratory water quality data (Bowie, 2014b), are summarized in Table 3 and copies of the lab <br />results are presented in Appendix B. There are no baseline water quality data for this well <br />(Bowie, 2014b). The post - rehabilitation field pH was 7.29 s.u. and the lab pH was 7.45 s.u. on <br />October 20, 2014. The field and lab conductivity values were 4,540 and 3,090 µmhos /cm, <br />respectively, and the water temperature was 16.0 °C on October 20, 2014. <br />The well's laboratory water quality results also included the following: hardness total 168 mg/L, <br />ammonia (0.15 mg/L), bicarbonate (3,440 mg/L), total dissolved solids (2,970 mg/L) calcium <br />(53 mg/L), iron total (22.3 mg/L), magnesium dissolved (8.64 mg/L), manganese dissolved <br />(0.086 mg/L), manganese total (0.295 mg/L), and sodium dissolved (1,220 mg/L). <br />Concentrations of arsenic, cadmium, carbonate, mercury, nitrate, nitrite and selenium were <br />below lab detection limits (Table 3 and Appendix B) (Bowie, 2014b). <br />The water in this well is sodium bicarbonate type (Figure 2). <br />November 2014 HydroCeo, Inc. <br />