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C1981012: TR68 SECTION 3.0 REVIEW <br />For comparison: <br />Alaterial weight data provided by NECC abs /C <br />Clean coal <br />1457 <br />Washed Coal Refuse <br />1916 <br />Topsoil <br />2055 <br />Subsoil <br />2132 <br />Gravel products 2396 <br />Alaterial weight data Cat Handbook 406, ed. abs C <br />Clean coal <br />1400 <br />Decomposed rock(25 %/75 %) <br />2650 <br />Earth -loam <br />2100 <br />Earth -dry packed <br />2550 <br />Gravel -dry <br />2550 <br />JANUARY 22, 2014 <br />In Section 3.0, page 4, NECC proposes that the vegetation failure rate should be reduced to 15% based <br />on reclamation experience at one mine adjacent to the New Elk Aline. The Division disagrees with this <br />projection. The Division recognized the reclamation success at the Golden Eagle mine, and approved <br />final bond release on all but a very small acreage. NECC stated that success at the Golden Eagle Mine <br />should be interpreted to mean that New Elk will have the same degree of success, is similar to stating <br />that if an area has not experienced an anticipated 25 year precipitation event in the past 25 years, that <br />they will not experience a 25 year event in the projected liability time frame. The failure rate ascribed to <br />the revegetation tasks represents a predicted probability for failure. <br />The Division considered NECC's argument previously and has already reduced the anticipated failure <br />rate from 50 %, based upon interviews with County Extension personnel in the 1995, to 33% based <br />upon NRCS soil survey for Las Animas County. (DRMS 2/1/2013 memo regarding 1VIT6 cost estimate <br />update) . <br />Upon review of failure rates applied at other mine sites throughout the state, along with correlating <br />precipitation, and seed mix, the Division disagrees with NECC's proposal to reduce the revegetation <br />failure rate to 15 %. <br />Moffat County - Craig: 13.28 inches Trapper: 17.5% failure rate <br />Colowyo: 20% failure rate <br />Delta County - Paonia: 15.39 inches Elk Creek: 50% failure rate rangeland <br />Terror Creek: 20% failure rate pasture <br />Bowie No. 2: 50% failure rate pasture <br />50% wells /pads <br />West Elk: 25% failure rate upland rangeland <br />50% failure rate steep slopes /roads <br />Fremont County -Canon City: 12.51 inches Southfield: 33% failure rate rangeland <br />50% failure rate tree transplants <br />Las Animas County - Trinidad Lake: 17.71 inches Lorencito: 50% failure rate rangeland <br />Trinidad: 15.55 inches Golden Eagle: 40% failure rate rangeland <br />New Elk: 16.92 inches (PAP) <br />La Plata County - Durango: 18.98 inches King Coal: 50% failure rate <br />1\Iancos: 16.86 inches <br />2 <br />