Laserfiche WebLink
<br />schedule for measurement instruments for various operational co~tions of the dam and mining <br />progress. The monitoring plan must also address the long-term, lingering effects after the coal is <br />extracted. I recommend installation of the instrumentation be completed and a detailed monitoring <br />plan be in place before mining proceeds inside a one mile radius of the reservoir. I believe the <br />timetable for the mine expansion on the revised plan provides ample time to complete the <br />recommended instrumentation and establish a monitoring plan. <br />On a positive note, I have been informed Bowie Resources made an agreement with the <br />Tenor Creek Ditch and Reservoir Company, owner of the dam, and began conducting subsurface <br />investigations of the embankments, their foundation and abutments, and the existing landslide. The <br />drilling program was initiated late last month, but not completed. When finished, the proposed <br />drilling program should satisfactorily address the first phase of a detailed instrumentation and <br />monitoring plan. [must assume Bowie Resources plans to mobilize the equipment again next spring <br />to complete the drilling program. Final selection of instrument types and locations cannot be fully <br />known until a seismic analysis of the dam and appurtenant features of the site is performed. <br />However, open standpipe type piezometers were installed in some ofthe investigation and sampling <br />holes during the drilline process. In summary, much remains to be done before a formal monitoring <br />plan is in place. <br />I hope the information provided is helpful and the recommendation does not impede the <br />schedule for issuing the permit. As always, call me if you have any question. <br />Sincerely, <br />es G. Norfleet, P.E. <br />Dam Safety Engineer <br />cc: Wayne Schieldt, Division Engineer <br />Alan Pearson, Dam Safety Branch <br />