REV01753 - Laserfiche WebLink

Home Browse Search

t~- 1 ~~ • III IIIIIIIIIIIIIIII sss ~~ Cripple Creek & Victor Gold Mining Company dUN 16 1995 A J01n1 Venture -Pikes Peak Mining company Manage PO. Box 191, 2755 State Highway 67, Victor, Colorado 80860 ~~ (719)689-2977 FAX (719) 6893254 June 15, 1995 RECEIVED Mr. Berhan Keffelew Environmental Protection Specialist Colorado Department of Natural Resources Division of Mines and Geology Office of Mined Land Reclamation 1313 Sherman Street, Room 215 Denver, Colorado 80203 C11VI61bH W NlI6tlfGtD a c~tltlltlgy Reference: Cresson Project• Permit M-80-244: Use of Detoxified Pad Materials -Pad 3. Response to OMLR concerns related to concentrations of nitrate and sulfate. Dear Mr. Keffelew: Yesterday you voiced concern that use of the Pad 3 materials could potentially adversely impact ground water quality. Your concerns were related specifically to nitrate and sulfate concentrations in comparison to drinking water standards and criteria. First, we wish to point out that the ground water in the vicinity of the Cresson Project is not a domestic drinking water source. Thus, drinking water standards and criteria should not apply. The neighboring towns of Cripple Creek, Victor, and Gold Fields rely on surface water sources not potentially influenced by the Cresson Project for domestic water. However, even if such standards and criteria did apply, the limited extent and intended use should not raise any concerns for ground water quality. From a mass balance standpoint, over 50% of the recharge to an aquifer would have to pass through the Pad 3 material before drinking water quality thresholds for nitrate or sulfate would be reached. While I have not spent the time to compute the maximum area that could be covered by such material it is clearly obvious that it is far less than 50% of any ground water hydrologic region. Furthermore, the primary use of the Pad 3 material will be for roadbase on mine roads. Repeated traffic rapidly compacts the surface, greatly reducing its permeability and its ability to contribute to ground water recharge. To put the quantity of nitrate in the Pad 3 material into perspective, an acre of compacted Pad 3 material with an average depth of one foot would contain approximately 61 pounds of nitrate nitrogen. Our present reclamation practices call for the application of 50 pounds of nitrogen per acre (150 lbs of 33-0-0 fertilizer). Agricultural applications of nitrogen frequently exceed 50 pounds of nitrogen per acre and sometimes exceed 100 pounds per acre. The quantity of