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~. ~ III IIIIIIIIIIIII III ~ STATE O~ COLORADO DIVISION OF ~VIINERALS AND GEOLOGY Depanmm~l of Natural Re,ources 1313 Shrrmdn 51., Room ? 15 Uens~cr, Colorario 80?03 RE'L+r' D I V I S I O N O F Phone: U03) 866-3557 e ~~~ MINERAL S FAX'. (3(131 83:-8106 ' ,1 ~~~ ~~ & MAR01 ypp~ ~~; ," F} ~~ GEOLOGY February zs, 2001 _ - -~-~ F~L.E ~+; ,..v~~ RECLAMATION OfYI HINING•SAFETY sionorMinereUs,naearl,,,,wl ~-~~L. '~~/~ LI Mr. William P. Balaz Jr. ~+~~-C,~ ~O B~BO~-en: Balaz and Associates C ,~ c°.er^°r P. O. Box 3300 ~/tS~r •, ~~~°~( Eregvlne Dveao, Grand Junction, Colorado 81502 'T/~ ~O Michael B. Long I „ ( Division DireUOr RE: Conger Harvesting Area, Permit No. M-1998-022, Technical Revision No.1 (TR-01) Second Adequacy Review Dear Mr. Balaz: The Division has completed review of your responses to the TR-01 preliminary adequacy review for the permit noted above. The application cannot be approved until the remaining problems listed below have been adequately addressed. Please submit your response as soon as possible, but no later than February 28, 2001 so the decision due date of March 1, 2001 can be met. If you cannot submit your response by February 28, 2001, please submit a written request for extension of the decision due date. If your response to this review, or a written request for extension are not received by February 28, 2001, the Division may have no choice but to deny this application. If an extension of this revision decision due date is requested, please also request an extension of the decision due date for the associated release request (AR-01). ADEQUACY COMMENTS Response acceptable for all proposed final slopes except those represented by cross section 0+50 where the final proposed outslope of the eastern switchback is shown steeper than 2H:1 V. It appears that the fill over this original outslope could be eliminated with minimal loss of bench area. If not eliminated, this outslope fill final grade will need to be reduced to 2H:1 V. Illustrated bench widths may not be extended where the extension would impact the required buffer zone for any of the 12 inch DBH trees on site, or where resulting inslopes/outslopes would be steeper than 1 H:1 V during their excavation or 2H:1 V at final configuration. Please correct the maps accordingly. 2. The-cross sections of the working mine bench illustrate several areas where the highwall is taller than the 20 foot maximum for slopes at or near a 1 H:1 V grade. Also there are current areas where slopes are steeper than 1 H:1 V that are 20 feet tall or taller. Please either provide a geotechnical demonstration that these active mining slopes will be stable, or revise the maps and cross sections so the slope specifications are consistent with the recommendations of the Lincoln peVore, Inc. report submitted with this application. Specifically see cross sections 0+50, staging, 2+00, 3+00, 5+00. 3. Please submit a reclamation plan map revised to address any changes made while responding to comments 1 and 2 above.