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May 23, 2003 Mr. James Burnell Colorado Division of Minerals and Office of Mined Land Reclamation 1313 Sherman Street, Room 215 Denver, CO 80203 REDEIV ED MAY 2 ~ 2003 pWision of Minerals end GeolelfY Geology Re: MR-69, Minor Revision to Permit No. C-1981-022, Borrow of Debris Deposit Material for East Fan Shaft Seal Backfill Dear Mr. Burnell: Many thanks for taking time from your busy schedule to travel to Somerset yesterday to meet with us regarding the proposed use of the debris deposit materials located east of the Sanborn Creek Mine ("SCM") portals for backfilling and sealing the SCM east fan shaft. As we'd discussed, Oxbow Mining, LLC ("OMLLC") was recently informed that its specialty contractor for installing the MSHA-approved, pumpable foam/cement-type mine seals in the SCM portals would only be available to complete this work for OMLLC during the first week of June. In order to safely seal the SCM in accordance with MSHA regulations, the last SCM portal seal and the east fan shaft backfill seal must be completed as soon as possible after the ventilation fan is stopped. Once the fan is turned off, the shaft backfilling and portal sealing will continue non-stop, until both are completed. To provide a readily available, continuous soil fill source for the SCM east fan shaft seal, OMLLC requests a minor revision to borrow approximately 4,000 yards of material from the debris deposit east of the SCM portals. As you'd observed yesterday, the proposed borrow source is a debris deposit fan comprised of soils and rock, created by many years of upland erosion and sediment deposition at the base of this unnamed, minor drainage. As access to monitoring well SC-1 had once traversed the debris deposit area, the existing disturbance boundary already includes this area (see attached map segment). OMLLC has estimated that the debris deposit contains approximately 38,000 yards in-place. Assuming a 2:1 finished cutslope, and blending the cut into the surrounding terrain, approximately 50% of the debris deposit material (or approximately 19,000 yards) would be available for borrow from this source. Additionally, upon reconsideration of the final reclaimed configuration of the SCM portals site to the west of the debris deposit, OMLLC will submit a separate technical revision application in the near future to utilize most, if not all, of the remaining 15,000 yards of available borrow material from the debris deposit. This material will be utilized to backfill the SCM portals sites and will allow the existing access road through this area (that is currently permitted to remain after