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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) 666 -3567 <br />FAX: (303) 832 -8106 <br />Ii►YY:011111342C4DI M AD] TOW11"r <br />TO: Marcia Talvitie <br />FROM: Mike Boulay jqf <br />DATE: June 11, 2010 <br />COLORADO <br />D I V I S I ON OF <br />RECLAMATION <br />MINING <br />— &L— <br />SAFETY <br />Bill Ritter, Jr. <br />Governor <br />James S. Martin <br />Executive Director <br />SUBJECT: Western Fuels- Colorado, New Horizon Mine (Permit No. C -81 -008), <br />Permit Revision No. 6 (PR -6) <br />As requested, I have reviewed Western Fuels -- Colorado's (WPC's) response to our adequacy <br />comment item no. 84. In WFC's response they indicate: In reviewing the entire Section 2.05.6(3) <br />Protection of the Hydrologic Balance, the location of a potential spoil spring was confirmed to be <br />exactly as that shown in this section. Minor additional language has been added, but the <br />evaluation of the impacts of a spoil spring at this location has previously been included in the <br />narrative of this section. 1 have the following comments regarding WFC's response. <br />84. The Division concurs with WPC's response and agrees with the analysis presented in the <br />PAP regarding the probable hydrologic consequences (PHC) of spoil spring development <br />and discharge. The Division also agrees with the estimated location for spoil spring <br />discharge from New Horizon #2 and the conclusion presented in the PAP that the Morgan <br />property should not experience any spoil springs. However, we believe that the discussion <br />should be updated and clarified based on our current understanding of irrigation flows. <br />The calculations beginning on page 2.05.6(3) -23 for the long term prediction for flow in the <br />spoil spring at the New Horizon #2 Mine is based on 418 acres of the spoil area being <br />irrigated. This presents a worst case scenario and results in a calculated volume of 485 acre <br />feet per year of flow in the spoil spring. This a relatively high flow for a spoil spring (300 <br />gallons per minute) and in fact the higher the flow the less potential impact to receiving <br />streams due to dilution and other factors. A more realistic scenario would be to use actual <br />irrigation amounts based on current information. If you include the irrigation flows on the <br />Morgan, Lloyd, and Benson properties this equates to about 150 acres of irrigation on spoil <br />area. Although this would produce less than 113 of the spoil spring flow presented in the <br />PHC, the end result may be greater water quality impacts to receiving streams due to more <br />concentrated flow. The Division believes that WFC should add to the analysis a more <br />realistic estimate to the spoil spring discussion and prediction. It would be useful to show <br />Office of Office of <br />Mined Land Reclamation Denver • Grand junction • Durango Active and Inactive Mines <br />