INSPEC36220

• Permit No: C1981039
• IBM Index Class Name: Inspection
• Doc Date: 10/6/1989
• Doc Name: INSPECTION OBSERVATIONS GRASSY GAP MINE PIT 5 C-81-039
• From: MLRD
• To: SUSAN MOWRY CATHY BEGEJ
• Media Type: D
• Archive: No

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STATE OF COLORADO
Roy Romer, Govei
DEPARTMENT OF NATURAL RESOURCES
MINED LAND RECLAMATION DIVISION
FRED R. BANTA, Director
DATE: October 6, 1989
T0: Susan Mowry
Cathy Begej
FROM: David Berry
RE: Inspection Observations -Grassy Gap Mine -Pit 5 - C-81-039
This memorandum is written to summarize my observations during our
September 29, 1989 inspection at the Grassy Gap Mine. Several possible
problems were noted at the Area 5 reclamation parcel. Please understand that
these are preliminary observations, and they are not meant to be conveyed to
the operator without considerable refinement.
Vegetation development on the steep, northeast facing, upper slope
does not appear to be progressing adequately, given the number of years
since seeding. Same active rilling was observed at this location. I
recommend that the area not be grazed since such activities appear to
be damaging the vegetation cover to such an extent that erosion continues
to occur.
Additional surface erosion may occur if the upland diversion ditch is
breached. I do not know if the upland diversion ditch is intended to
be a permanent structure; however, the final drainage design for the
reclaimed Pit 5 should not rely on the upland ditch.
3. It should not be necessary to rely on the contour furrows for surface
stabilization at such a late stage in the reclamation. Rather,
vegetation should be the main stabilizing component. The operator
representative indicated that furrow breaches still occur, which causes
downslope erosion. I recommend that the operator focus upon enhancing
the upland vegetation cover, rather than relying upon the contour
furrows. The furrows should not be deepened; however, specific breach
locations should be repaired. This is necessary since the furrows do
collect and concentrate flow.
The existing reclaimed topography should have been designed to more
closely approximate the original contour. Amore stable configuration
should have been approved and/or implemented. It is probably unrealistic
to expect any significant regrading; however, I feel that it is
appropriate to note that the existing and potential erosion problems
might have been avoided with a bit more planning.
215 Centennial Building, 1313 Sherman Street Denver, Colorado 80203-2273 Tel. [phone]