Laserfiche WebLink
<br />~ ~ o ROCKY MOUNTAIN GEOTECHNICAL, INC. <br />Achieving Harmony with Earth <br />October 4, 1982 <br />Mr. Dean Massey <br />Dorchester Coal Company <br />9350 E. Arapahoe, Suite 300 <br />Englewood, CO 80112 <br />Attn: Dean Massey: <br />CERTIFICATION OF <br />ROCK-DRAIN INSTALLATION <br />DORCHESTER #1 MINF. <br />llear Dean: <br />On September 27, 1982, personnel from Rocky Mountain Ceotechnical <br />inspected the rock drain at the Dorchester #1 Mine. The following <br />observations were made during the inspection: <br />o The rock drain was e;:posed at the upstream and <br />downstream end of the existing refuse pile. <br />o The exposed rock drain was observed to have been <br />constructed according to the design recommendations <br />set forth in the Rocky Dountain Report entitled, <br />"Reconstruction Plan and Storage Optimization". <br />o Flow was observed at the downstream exposed por'~ion <br />of drain (flow was apparently due to internal seepage <br />from recent storm events). <br />Based on the above observations, it is Rocky fountain Geotechizi.cal's <br />opinion that the rock drain under the existing refuse pile, for <br />the Dorchester #1 Mine, was constructed according to design recom- <br />mendations and is functioning properly. We do, however, recommend <br />that the drain be extended and maintained at least 20 feet beyond <br />The Railroad Station • 555 E. Pikes Peak Avenue, Suite 107 • Colorado Springs. Colorado 80903 • (3031 634-1999 <br />