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III IIIIIIIIIIIII III 999 United States Department of the Interior -:cLt)vEp BUREAU OF LAND b1ANAGEh1ENT N~~ f) 9 1998 UNCOMPAHGRE BASiN RESOURCE AREA ,is~cn ci Minerals & Geolo 2505 SOUTH TOWNSEND AVENUE 9Y MON"I7tOSE, COLORADO 81401 3400 COC-37210 COC-27432 COC-25079 COC-53356 COD-036955 CO-034 Steve Walcott P.O. Box 6 Paonia, CO 81428 Dear Mr. Wolcott: NOV 2 1998 We received your letters commenting on the Iron Point Tract and requesting information on the existing Bowie #1 Mine coal leases. We want to assure you that the lease stipulations are being followed. The leases including the special stipulations are attached. We couldn't find a requirement for water resource "monitoring until ten years after the lease expires" in any of the special stipulations. The stipulations do say the existing on-tract and cross-tract water flows will be maintained and as you suggest, the best way to do this is to measure the water flows on a continual basis. This is being done and annual hydrologic reports are submitted each year to the Colorado Division of Minerals and Geology (CDMG) as a part of the Bowie #1 permit requirement for their mine plan (Permit C-81-038). We are in the process of getting you copies of the monitoring data for the East Roatcap and West Roatcap drainages as requested. We will send you the data in the near future. Enclosed for your review is the water replacement plan and the sections in the CDMG mine plan which address water (Hydrologic Appendices, Section 2.04.7, Section 2.05.6 etc.). There have been Technical Revisions to the mine plan involving hydrology, that were available for public review as listed in legal notices in the newspaper. In some cases, where mining had never occurred or was completed, monitoring of water data may be reduced or stopped. There is approximately 1000 feet of overburden between the springs in the Long Draw area and the underlying coal. There is more overburden over the mined out area closest to the springs. See the attached map for overburden contour lines and mined out areas in the East and West Roatcap Creek drainages. The area above the mined out coal is about 1400 feet from the closest spring. Current scientific data maintains that mining will not cause surface cracks when the overburden is 60 times the mined height (60 X 14 feet = 840 feet), or in this case where the overburden is greater than 840 feet. Using the scientific data, the area above the mined coal will not drain water into the mine and there will be no loss of surface flows due to mining. In addition, using the 25° angle of draw and the overburden of 1200 feet over the mined area, subsidence could affect up to 560 feet from the outside edge of the mined area. Since the springs are 1400 feet from the outside edge of the mined area, the calculations indicate the springs would not be affected. Portions of East Roatcap Creek are protected by buffer zones. There was one entryway which undermined the East Roatcap Creek buffer zone. The entryway was for development only; this means that the pillars were not pulled and they were left in place to prevent surface subsidence in order to ensure protection of water resources and riparian values. The safety factor of the pillars left in place is enough to support the overburden. The attached map shows the areas under East Roatcap that were undermined. In addition, in accordance with the lease stipulation 15 (D) of lease COC-37210, the water in East Roatcap Creek was diverted to West Roatcap Creek via the Overland Ditch around the coal lease and delivered to the original paints of use. The surface flow water in East Roatcap is being monitored according to the water monitoring plan in the CDMG Permit. No mining has occurred under