Laserfiche WebLink
<br />STATE OF COLORADO <br />DIVISION OF MINERALS AND GEOLOGY <br />Depanmenc of Nawral Resources <br />1 } I S 7herman $t., Room '_ 15 <br />Denver, Colorado 80203 <br />Phone: 1303) 866-3567 <br />FAt: (3031 832-8106 <br />April ]0, 2000 <br />Michael G. Altavilla <br />Seneca Coal Company <br />P.O. Box 670 <br />Hayden, CO 81639 <br />Re: Yoast Mine (Permit No. C-94-082) <br />Technical Revision No. 12, Adequacy Review <br />Dear Mr. Altavilla: <br />DIVISION OF <br />MINERALS <br />GEOLOGY <br />0.ECLA MA710N <br />MINING•SA FETY <br />Bill O..~ens <br />Governor <br />Greg f. LValcher <br />Ezecuuve Director <br />Michael B. long <br />Division Dueclor <br />The Division of Minerals and Geology (Division) has reviewed the technical revision <br />application materials submitted for Seneca Coal Company's (BCC's) as-built report and <br />certification for sedimentation pond 012. Several deviations from the design (Proposed Pond <br />012 Design Exhibit 13-12.2, 6/99) to the as-built structure were identified. However, a review of <br />the revised SEDCAD demonstration and Pond 012 As-Built Exhibit 13-6, 3/00 indicate that the <br />as-built structure will perform in compliance with Division rules. This letter presents the <br />Division's adequacy comments for the as-built submission. <br />The details of the trash rack should be added to the as-built drawing (Exhibit No. 13-6). <br />2. Please add as-built certification for the Dminimum emergency spillway riprap <br />specification. <br />3. Please explain or remove the bottom of pond notation at elevation 7230' in the Pond 12 <br />Stage Capacity Table on Exhibit 13-6. <br />4. The gated dischazge pipe installed below the principal spillway is not shown on the as- <br />built certification. Please add this to Exhibit 13-6. <br />5. Please notify the Division if any of the information submitted in the as-built report and <br />certification has changed due to the slide that recently occurred above Pond 012. If SCC <br />