REV97379

• Permit No: C1980007
• IBM Index Class Name: Revision
• Doc Date: 12/16/1998
• Doc Name: MR 250 WATERTANK SAW WEST ELK MINE PN C-80-007
• From: DMG
• To: JIM BURNELL
• Type & Sequence: MR250
• Media Type: D
• Archive: No

iii iiiiiiiiiiiiiii
STATE OF COLOl~~9~
DIVISION OF MINERALS AND GEOLOGY
DePjriment of Nalu ral Resource
1313 Shcrntan 51., Room 215
Dearer, Colorarlu N0203
Phone: (3031 N66J567
FA%: (311]1 83?-H106
DATE: December 16, 1998
TO: Jiro Burnell
FROM: Joe Dudash
RE: MR No. 250, Watertank SAE, West Elk Mine, Permit No. C-80-007
r~r
~~~~~~ P
DEPARTMENT OF
NATURAL.
RESOURCES
Roy Romer
Governor
lames 5. Lxhhead
Eneculiae Director
nhchaei B Lonl;
Division Duecmr
As you had requested, I reviewed the hydrology designs for the watertank SAE, in order to
determine whether the silt fence at the bottom of the grassy slope downgradient of the watertank
pad can be removed. The SAE designs are located in Volume 8A-2.
In my review, I found that there aze no SAE designs for the grassy slope downgradient of the
watertank pad. There are only SAE designs for the cut slope above the watertanl: pad and the
watertank pad itself. The SAE designs for the cut slope and the watertanl: pad demonstrate that
effluent limitations can be met without the aid of silt fence or any other sediment control
stnlcture at the edge of the pad area. This, however, is not the end of the story.
One question that needs to be answered is whether the grassy slope downgradient of the
watertank pad had been disturbed by the mining operation? If it was, then the operator should
submit an SAE design for that grassy area. It is possible that such an SAE design aright require
silt fence at the bottom of the grassy slope. If [he grassy slope was not disturbed by mining, then
no additional designs need to be submitted.
As you had discovered by reviewing aerial photographs taken of the area during the time of
construction, a large azea of the grassy slope had been disturbed by mining activity. Therefore,
[he Division should request that the operator submit hydrology designs for the grassy slope
portion that was disturbed. Those designs will determine whether or not silt fence is required. In
the meanwhile, the silt fence at the bottom of the grassy slope should remain and be in good
condition.
If you have any questions, please let me know.
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