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TRAPPER MINING INC. iii iiuuiiiiiii iii October 19, 2000 RECEIVED OCT 19 2000 Mr. Tom Kaldenbach Environmental Protection Specialist Colorado Division of Minerals and Geology 1313 Sherman St. Room 215 Denver, CO 80203 Division of Minerals and CeoloAY Re: Permit No. C-81-010; Technical Revision TR-84; Probable.H}1;dkg14p,1c;Cott~eq~^~a. Dear Mr. Kaldenbach: In response to your initial review of the text changes proposed under TR-84, Trapper is providing the following submittal. Each of the "bubble" comments you provided is addressed as described below and duplicate copies of the revised PHC text are provided. The numbered responses below correspond to the comments provided in your correspondence dated May 26, 2000. I.) The PHC text has been revised to indicate that a generalized assessment of recharge vs. discharge in the D and E pit areas suggests D pit spoil springs are likely to form and E pit spoil springs are less likely to form. With respect to E pit, this conclusion is more sensitive to the accuracy of the assumptions utilized regarding infiltration, underburden inflows, and pit discharge. 2.) The PHC text has been revised to indicate that a spoil spring is unlikely to form in East A pit. This text has been moved to appear under the Aquifer Restoration discussion following the D/E pit spoil spring assessment. 3.) See response to comment 5. 4.) This paragraph was deleted per your request. Trapper is no longer attempting to utilize regraded spoil sample results to make inferences regarding spoil quality throughout the mine. Trapper concurs with the Divisions observations that a high degree of mineral content variation occurs in spoil and that near surface weathering appears to act quickly to weather and leach materials out of shallow spoil. 5.) Backfill water quality to date shows a high degree of variation at Trapper. This variation is attributed, at least in part, to the documented variation in pyrite content expressed in the available core hole data. [n the USGS study conducted at the Seneca Mine, water quality at the Spring Creek site was consistently lower than water quality from the Cow Creek site (see page 42). This difference was attributed to the presence of a spoiled coal seam in the vicinity of the Spring Creek study area. The coal seam "contains large quantities of pyrite which, when oxidized, probably contribute substantially to the dissolved solids in mining-affected water. Therefore, larger P.O. Box 187 Craig. Colorado 81626 (970) 824-4401