Laserfiche WebLink
0 1% 111, iq�;i <br />111111 1 <br />DIVISION OF RECLAMATION, MINING AND SAFETY <br />Department of Natural Resources <br />1313 Sherman St., Room 215 <br />COI O R A I0 O <br />Denver, Colorado 80203 <br />D l V f S I O N O P <br />Phone: (303) 866 -3567 <br />RECLAMA <br />FAX: (303) 832 -8106 INTEROFFICE MEMORANDUM <br />t�tt &- <br />SAFETY <br />Date: 24 March 2011 <br />John W. Hickenlooper <br />Governor <br />To: Susan L. Burgmaler <br />Mike Kin <br />Executive Director <br />From: Marcia L. Talvitie, P.E. <br />Loretta E. Pineda <br />Director <br />Subject: Seneca II -W Mine (Permit No. C- 1982 -057) <br />T'R -73 — Pond 016 Area Slide Remediation Plan <br />Adequacy Review — Engineering / Geotechnical <br />Pursuant to your request, I have reviewed Seneca Coal Company's (SCC) application for TR -73. <br />Provided with the application is Attachment 20 -D Pond 016 Area Slide Remediation Plan, <br />prepared for SCC by NorthWest Colorado Consultants, Inc. (NWCC). <br />The NWCC report provides recommendations for repair of three landslide features: ENE of <br />Pond 016, ESE of Pond 016A, and NW of the Shrub Plot. The recommendations are made based <br />upon a series of field observations and subsurface investigations. <br />My comments are detailed below, for your use in responding to SCC with the Division's <br />adequacy review of TR -73. <br />Pond 016 Landslide <br />Site observations for this slide area are provided beginning on page I of the NWCC report; <br />recommendations for mitigation of the slide begin on page 4. <br />Failed materials (fill and overburden) will be removed to competent bedrock (0.5H:1 V) <br />or highly weathered bedrock and overburden (2H:1 V or flatter) <br />Groundwater will be intercepted at base of excavation, by rock drain constructed in <br />competent bedrock <br />Field fit, as necessary, depending on what excavation reveals <br />The Division finds the approach described for repair of the pond 016 Landslide to be <br />acceptable, and has no adequacy comments at this time. <br />'pct ( � ,ra � <br />Site observations and subsurface investigations are described beginning on NWCC page 2. <br />Office of Office of <br />Mined Land Reclamation Denver ® Grand Junction • Durango Active and Inactive Mines <br />