REV15122 - Laserfiche WebLink

Home Browse Search

~_ • • IIIII~III~I~~~~~'ll STATE OF COLG~~~ Roy Romer, Gove DEPARTMENT OF NATURAL RESOURCES MINED LAND RECLAMATION DIVISION FRED R. BANTA, Director DATE: December 18, 1987 T0: Gregg Squire FROM: Jim Stevens aL7 RE: TRAPPER MINE (PERMIT N0. C-81-010) PR-2 AND PERMIT RENEWAL ADEQUACY RESPONSE DATED DECEMBER 8, 1987 Hydrologic Balance - Ground Water Trapper Mine has objected to my requesting a commitment by them to annually inventory springs and seeps along the downdip margins of their pits and to add the significant ones to their monitoring plan. They have provided their interpretation of various of the rules to support their refusal to do so. Rule 2.05.6(3), one of the rules cited, is a permitting rule of which a portion, Rule 2.05.6(3)(b)(iii), requires a plan for monitoring ground water quality and quantity accordin to Rule 4.05.13. Rule 4.05.13 is a performance rule that Trapper does not re erence 1n ter response but is one I interpret as requiring a monitoring plan acceptable to the Division as providing adequate data on the effects of mining on ground water quantity and quality...utilizing wells or other sources for ground water levels and quality... so that modification of the mining activity can be made, if necessary, to minimize disturbance of the prevailing hydrologic balance. Under the hydrologic circumstances at Trapper Mine, springs and seeps can provide timely and relatively convenient sources of ground water data useful for the purposes stated in Rule 4.05.13, and there are a number of areas where future springs might arise along the backfilled, northern, downdip margins of the pits. Contrary to Trapper's claim, their existing or currently proposed monitoring wells in the spoils do not in themselves provide sufficient ground water 1eve1 and quality data for all these areas of future interest, eq. the Colt and Browning Pit area, the Coyote Draw area, and the eastern pits. The desired data on ground water quality, levels etc. might reasonably be secured in these areas by the installation of additional monitoring wells, but Trapper Mine has not in the past been installing additional wells in the backfi]led pits (or in adjacent undisturbed areas) unless utility wastes are disposed up gradient. Furthermore, while it mdy be true that the quality of the surface discharges of the present and future springs would be monitored to some extent at the various NPDES discharge points, at most of these points the majority of dissolved 423 Centennial Building, 1313 Sherman Street Denver, Colorado 80203-2273 Tel. (303) 866-3567