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.... ~_ : _ _. _ . iii iiiiiiiuiiiiii . STATE OF COLORADO DIVISION OF MINERALS AND GEOLOGY Deparlmem of Natural Resources 1313 Sherman Sr, Room 215 RECEIVED Denver, Colorado 90207 DIVISION O F Phone: (303) 866-3567 MIN & R A L S ~ ~oo~ FAX: (3031 83'-8106 C [ B 2 DATE: February 13, 2001 f C G E O L O G Y Division of Minerals 8 Geolom' RECLAMATION MINING • 5 A F E T Y TO: Jim Stark n `~~ FROM: Dan MaUtews 111 gill Owens eo~ernor RE: Review of Roadside Cost Estimate "On-the-Ground" Creg E Watcher Executive Dneuor Roadside Mine (Permit No. C-81-041) Michael g. Lung Division Ducaor This is an update of my memo of February 1, which you apparently did not receive. Tltis memo incorporates soil stockpile volume estimates I made at the mine last week, and also includes comments based Dn my review of the February 2, 2001 "On-Ute Ground" cost estin>ate you completed. I assume Ut at you will be refining the "on the ground" estimate based on certain comments which follow, as well as comments received from other reviewers. Please let me know if you have any questions. Re ve ¢etat i on'Acrea ¢e I crosschecked reclamation acreage assumed in Ute cost estimate against perntit projections to verify that they correspond. The cost estimate assumed a total area of 236 acres to be revegetated. This figure matches up very closely with [he actual disturbed area acreage of 242.6 aces from Permit Table 12-1, which was updated m March 2000 by TR-31. The small apparent discrepancy would be accounted for by road disturbances approved for permanent retention. The revegetation cost assumptions could be considered somewhat conservative, because approximately 46 acres of Ute total have previously been permanently revegetated. However, this acreage Itas not been released from bond, and in [Host cases the 10 year liability period since initial seeding has not passed. Recent monitoring and observations indicate that a number of Ute reclaimed areas would likely not meet all of Ute revegetation success standards, at Utis Um.e. Far these reasons, I believe the aaeage figtues used in Ute "on the ground" revegetation cost tasks are appropriate. CRDA-1 and CRDA-2 Cover Soil and Toodressina Volumes The original RN-03 cost figures for CRDA-1 and CRDA-2 non-toxic cover soil and topdressing appeared overly conservative, for two reasons. First. it appeared Utat the cost assumptions were based on outdated requirements (3 feet of cover and 1 foot of topsoil). Current requirements aze l fool of cover and 6 inches of topsoil on CRDA-l; with l8" of cover and 6" of topsoil on CRDA-2. Second, it appeared Utat the estimate did not reflect Ute fact Utat 1 I acres of CRDA-I and 7.6 acres of CRDA-2 Itad been covered, topsoiled, and stabilized in 1994. Compliance with cover/topsoil replacement thickness has previously been verified by DMG. 1 noted in reviewing Ute "on the ground" estin><~te that you made certain dowmvard adjustments in cover/topsoil volumes, to better [Hatch actual requirements attd conditions. I scrutinized U1e adjusted volumes pretty closely, based on my field meastuements, permit requirements and projections. InformaUOn regarding material volumes, and disturbed and reclaimed acreages for the CRDA refuse areas, CBA-2 borrow area, and We North Portal Facility Area is presented in Table 14-lof Ute PAP. Relevant acreages correspond closely to acreages specified in Table 12-I. Topsoil Stockpile volume information is presented in Table 14-2 of the PAP. [n order to verify that the stockpile volumes listed in Ute permit were reasonable, I conducted field volume checks of certain stockpiles, as well as soil currently stored as sediment in Ute Coal Creek permanent diversion. I conducted the field checks on February 7 and February 8, 2001. Measurements of slope and