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Final Technical Report, 2014 Monitoring Well Rehabilitation Program Bowie Mine 11 <br />2.4 Well CWI -DH -60 <br />Monitoring well CWI -DH -60 was cleaned and rehabilitated between August 20 and August 23, <br />2014. The RACS workover rig was used to clean the well using a jetting tool from 1,055 feet to <br />bottom of the well at 1,085 feet. Approximately 15,000 gallons of water were jetted into the well <br />to clean the upper 1,055 feet of 4 -inch well casing. Initial return water from the well was sludge <br />like and gray -black color. The water gradually cleared during jetting and included tiny particles <br />of black coal with tan color silty sand particles, followed by mostly clear return water at the end <br />of the process. On August 22, 2014, the well was then evacuated using the airlift and bailing <br />techniques and the water quality showed a pH of 7.70 s.u., conductivity of 863 µS /cm, and <br />temperature of 20.5° C. After a 12 hour recovery period, the SWL was measured at 892.0 feet <br />btoc (August 23, 2014). <br />A video inspection of the well showed clean 4 -inch steel casing down to about 1,055 feet where <br />the camera was unable to descend past the cross -over from 4 -inch steel casing to 2 -inch PVC and <br />into the screened interval. To confirm the well water quality, once again the well was <br />continuously bailed for 1.5 hours and field water quality measurements were taken every 15 <br />minutes. On August 23, 2014, the average pH was 7.84 s.u., the average conductivity was 901 <br />pS /cm, and the average temperature was 20.7° C. At this point, the well was deemed functional <br />and successfully rehabilitated and developed. The well completion diagram is presented in <br />Appendix A. A water quality sample will be collected for laboratory analysis in October 2014 <br />using a stainless steel point source bailer. Laboratory water quality data will be summarized in a <br />subsequent report. <br />Photo 7 — Well CWI -DH -60 Lowering Bailer <br />November 2014 1 HydroGeo, Inc. <br />