Laserfiche WebLink
COLORADO <br />Division of Reclamation, <br />Mining and Safety <br />Department of Natural Resources <br />1313 Sherman Street, Room 215 <br />Denver, CO 80203 <br />Interoffice Memorandum <br />September 1, 2016 <br />From: Leigh Simmons <br />To: Zach Trujillo <br />Subject: Munger Canyon Mine (Permit No. C-1981-020) <br />TR -27 <br />Per your request, I have reviewed the material submitted by the operator with the application <br />for TR -27. <br />TR -27 proposes to seal two groundwater monitoring wells, GW -5 and GW -6. The operator cites <br />as justification the fact that both wells are dry. <br />In conducting this review I looked at the currently approved Permit Application Packet (PAP) as <br />well as recent Annual Hydrology Reports (AHRs). Section 4.4 of the PAP describes the <br />hydrogeology of the site in some detail; the following key points are made: <br />The mine is situated sufficiently far above the water table that there is no realistic <br />potential for impact of mining activity on bedrock groundwater <br />The mine is located above alluvial fills, and does not directly disturb them <br />Alluvial water in the area is of limited quantity and generally poor quality <br />In light of these physical conditions the groundwater monitoring program is extremely limited, <br />and is described in a single page in section 2.6 of the PAP. A summary of wells GW -1 through - <br />8, (with generalized construction information as well as the surface elevation, total depth, <br />perforated interval and depth to water of each well) is given in figure 4.1-7. <br />The currently approved groundwater monitoring program requires the quarterly monitoring of <br />wells GW -1, -3 and -6 (locations shown on figure 2.3-5) for field parameters and water level. <br />GW -2, -4, -7 and -8 are reported as sealed in 2007. GW -5 is not mentioned. <br />The most recent AHR (2014), provides monitoring data from GW -1, -3 and -9, although GW -9 is <br />not described in the PAP, nor is it shown on figure 2.3-5. (GW -9 is part of the neighboring <br />McClane Canyon Mine permit, and the AHR for both mines is combined into a single report). <br />No mention is made in the AHR of GW -5 or -6. <br />pF COlO <br />H <br />1313 Sherman Street, Room 215, Denver, CO 80203 P 303.866.3567 F 303.832.8106 http://mining.state.co.us I <br />John W. Hickenlooper, Governor I Robert W. Randall, Executive Director I Virginia Brannon, Director ** <br />