Laserfiche WebLink
STATE OF COLORADO <br />DIVISION OF RECLAMATION, MINING AND SAFETY <br />Department of Natural Resources <br />1313 Sherman St., Room 215 <br />Denver, Colorado 80203 <br />Phone: (303) 866 -3567 <br />FAX: (303) 832 -8106 <br />INTEROFFICE MEMORANDUM <br />TO: Marcia Talvitie <br />FROM: Mike Boulay Mb <br />DATE: October 14, 2011 <br />COLORADO <br />D IV IS I ON OF <br />RECLAMATION <br />MINING <br />SAFETY <br />John W. Hickenlooper <br />Governor <br />Mike King <br />Executive Director <br />Loretta E Pineda <br />Director <br />SUBJECT: Western Fuels - Colorado, New Horizon Mine (Permit No. C- 1981 -008), <br />Partial Phase II and III Bond Release SL -12, Groundwater Review <br />I have reviewed Western Fuels- Colorado's (WFC's) bond release application (SL -12) specifically <br />regarding groundwater quantity and quality impacts. WFC did provide a surface and groundwater <br />quantity and quality impact analysis in Item 5 page 19 of the SL -12 application. I concur with their <br />conclusions in Item A) Impact on Ground Water Rights and B) Impact of Spoil Material on Ground <br />Water Flow and Recharge. I do not believe that WFC's conclusions regarding impacts of replaced <br />spoil on groundwater quality are substantiated. I have the following comments that should be <br />forwarded to the operator. <br />Concerning impacts from the conversion of overburden to spoil, WFC states that a small <br />proportion of the overburden may produce acid through the oxidation of pyrite. In Item C) <br />Potential impacts of replaced spoil on groundwater quality beginning on page 20 of the SL- <br />12 application WFC presents the following discussion. Calcite is present throughout the <br />overburden. The calcite will serve to buffer the pH of the water slowing the oxidation of <br />pyrite and secondly it will neutralize the acid that is produced. The Division generally <br />agrees with this analysis. However the demonstration for this is not substantiated. WFC <br />states that Well GW -N40, which is southwest of the Phase 3 reclaimed area, best represents <br />the spoil water. However, WFC states on pages 19 and 20 "...no springs have developed <br />anywhere in this area. Well GW -N40 is located immediately down dip from the release <br />areas, and will show any changes in ground water quality before any spring developed on <br />the surface." Since WFC has reported no groundwater quality changes at GW -N40 it <br />clearly shows that GW -N40 is not a good representation of spoil water quality. Further, <br />GW -N40 is a shallow well with a total depth of thirteen feet with a slotted interval from 3.0 <br />-13.0 feet. The well is located outside of the disturbed area and it monitors the alluvium <br />adjacent to Calamity Draw. Water quality would be expected to be relatively good since it <br />monitors infiltrating meteoric and irrigation water and may be directly influenced by flow in <br />Calamity Draw. No further information is presented to show that water samples from GW- <br />Office of Office of <br />Mined Land Reclamation Denver • Grand Junction • Durango Active and Inactive Mines <br />