_GENERAL DOCUMENTS - C1981017 ‎(165)‎

• Permit No: C1981017
• IBM Index Class Name: GENERAL DOCUMENTS
• Doc Name: Bid Documents ‎(IMP)‎
• Permit Index Doc Type: General Correspondence
• Media Type: D
• Archive: No

STATE OF COLORADO
DIVISION OF MINERALS AND GEOLOGY PFV7
�
Department of Natural Resources
1313 Sherman St.,Room 215
Denver,Colorado 80203
Phone:[phone]
FAX:[phone]
DEPARTMENT OF
November 3 , 1994 NATURAL
RESOURCES
MEMO Roy Romer
Governor
TO: Maintenance File James Lochhead
Executive Director
FROM: Steven Renner Michael B Long
Drvision Director
RE: Stream Channel Modifications
After discussing the proposed stream channel modifications (laying
steel plates horizontally in the channel, rather than building
vertical rock traps) it was agreed in the field to utilize 3 feet
by 3 feet expanded metal plates bolted to the channel. It was felt
that the expanded metal would provide protection from abrasion by
large diameter rocks while trapping smaller grained particles above
the cement. The 3 feet by 3 feet dimension was agreed upon as it
is of a size that would pass through the 8 feet diameter culvert
without blocking it.
Mike Frick of Dirt-N-Iron provided 8 sections of the expanded
metal . John Reeves Senior had given his permission to allow the
salvage of additional expanded metal from the scrap material
stockpiled at the site. Mr. Reeves stated that he thought that the
total thickness of the concrete channel was 9 inches. Lew Thompson
of Pitkin Iron and I observed that the eroded areas of the channel
are worn to a depth of about 6 inches on September 20, 1994.
Mr. Frick attempted to drill holes in the cement channel to anchor
the expanded metal plates. Due to either the hardness of the
concrete materials of the presence of rebar in the concrete, he was
unable to complete a hole at a depth of greater than about 2
inches. We attempted to anchor an expanded metal plate using these
2 inch holes, but found that insufficient anchoring was provided,
and the expanded metal plate was unstable.
I was concerned that should one or more of the plates become
dislodged during run off, they could become entangled upon a down
stream plate or its rebar anchoring. system. I became concerned
that, due to the apparent lack of cohesion to the base of the
channel, the potential for the dislodgement of a plate and a
potential partial blockage of the channel could cause more
environmental damage than it would accomplish. This is
particularly true if these conditions caused the channel to over
top or divert away from the inlet to the concrete channel . I
directed Mr. Frick to not attempt to secure any other plates until