PERMFILE67588

• Permit No: M2002120
• IBM Index Class Name: Permit File
• Doc Date: 5/23/2003
• Doc Name: DMG Acceptance and Clarification of Proposed Flood Mitigation Measures
• From: DMG
• To: DMG
• Media Type: D
• Archive: No

STATE OF COLORADO
DIVISION OF MINERALS AND GEOLOGY
Department of Natural Resources
1313 Sherman St, Room 215
Denver, Colorado 80203
Phone: [phone]
FAX: [phone]
DATE: May 23, 2003 V
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COLORADO
DIVISION O F
MIN SRALS
GEOLOGY
0.EC LAMATION•MINING
SAFETY•SCIEN CE
TO: Kate Pickford, DMG
FROM: Allen Sorenson /(l/
RE: Floodplain Mitigation Measures, Bernhardt Resource Gravel Pit,
Hall Irwin Corporation, Permit No. M-2002-120 ./
Bill Owens
Governor
Greg E. Walther
Executive Director
Ronald W. Cattany
Division Director
Natural Resource Trustee
The Division of Minerals and Geology has completed a review of the letter report dated March 25,
2003 prepared by Civil Resources as technical consultant to Hall Irwin Corp. The report lists and
describes certain excavation and reclamation backfilling procedures to stabilize the mining pods
during flooding up to and including the 100-year flood. Among the stabilizing measures proposed
is that mining within 200-feet of the river will be limited to Fall and Winter months when the
potential for damaging flood events is virtually eliminated. Civil Resources further proposes to
backfill the pit walls to create finished slopes no steeper than 5:1 within 200 feet of the river. In
order for these proposals to be effective, all mining within 200 feet of the river must occur between
the dates of October 1 s` and April 1 s` during any given year of operations and backfilling and/or
grading of mined slopes within 200 feet of the river to 5:1 or flatter must be completed by April ls`
of each year. If this specification is adhered to by the Operator, and the other mitigation measures
in the March 25, 2003 Civil Resources letter are followed, then the potential for adverse flood
related impacts caused by mining of the pits will be minimized. Please assure that the actions
proposed in the Civil Resources letter are enforceable components of the permit, and that the
definition of the low flood hazard period provided above is communicated to and understood by the
Operator. A simple summarization of the requirements for mining and grading within 200 feet of
the river is as follows:
The presence of any mined slopes, graded slopes, and/or backfilled slopes at the Bernhardt
Resource site that are steeper than 5:1 and are within 200 feet of the river during the period
from April 15` to October I51 of any year would be a violation of mined land reclamation
permit M-2002-120.
cc: Carl Mount, DMG (via email)
Brad Hagen, Civil Resources (via fax)
caacsVNy Documen[s~Bemhardt flood plan appvl.doc
Office of Office of Colorado
Mined Land Reclamation Active and Inactive Mines Geological Survey