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Savage and Savage Environmental <br />practical solutions for environmental issues <br />4610 Haystack Drive 970 674 8080 telephone <br />Windsor, Colorado 80550 970 674 8088 facsimile <br />savageandsavage@earthllnk. net <br />December 9, 2005 <br />Ms. Janet Binns, Environmental Protection Specialist <br />Colorado Division of Minerals and Geology <br />1313 Sherman Street, Room 215 <br />Denver, Colorado 80203 <br />Re: Keenesburg Mine Phase II Bond Release SL-03 Adequacy 2 Response <br />(CDMG file C-81-028) <br />Dear Janet: <br />Seeking clarification of your December 2, 2005 request, Byron Walker and I discussed <br />all factors and came to agreement on appropriate values for use in the USLE <br />sedimentology demonstration for the Keenesburg Mine. Based on our discussions I am <br />forwarding the following information for the file. <br />Based on our discussions, we agreed on the values of LS factors for the USLE calculation <br />for the Keenesburg Mine using the nomograph Figure 2 from TR51. I did this in two <br />ways; first I took the slope length and slope angle from my original submittal for the <br />native azeas (742' slope, with 2% slope angle) and derived an LS value of 0.7, second I <br />drew four cross sections (one in each quadrant, N, S, E, and W) in native areas outside <br />the mine permit area, and calculated a mean slope and subsequent LS factor of 0.017 <br />(please see attached map). <br />Cross Section Elevations Elevation <br />Change Total XS <br />Distance % Slope <br />(uniform over <br />distance <br />A-A' (south) 4870-4830' 40' 2000' 2.0 <br />B-B' (east) 4800-4770' 30' 2000' 1.5 <br />C-C' (north) 4770-4760' 10' 2000' 0.5 <br />D-D' west) 4860-4820' 40' 2000' 2.0 <br />We also used Figure 2 from TR51 to recalculate the LS for the reclamation azeas. The <br />LS for the reclamation areas (for a mean slope length of 507' and slope angle of 0.885°) <br />was 0.27. <br />