PERMFILE107879

• Permit No: M2004044
• IBM Index Class Name: Permit File
• Doc Date: 8/22/2004
• Doc Name: Adequacy Review Hydrology
• From: DMG-Berhan Keffelew
• To: DMG-Larry Ohler
• 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]
August 22, 2004
COLORADO
DIVISION OF
MINERALS
GEOLOGY
RE<IAMATION•MINING
SAFETY•SCIENCE
Bill Owens
/ Governor
TO :Larry Older v Russell George
Executive Director
Ronald W. Cattany
From : Berhan Keffelew ~ Division Director
/ Natural Resource Trustee
t/
Re: Adequacy Review, Hydrology M-2004-044.
As you requested, I have reviewed Exhibits "D", "E", "G" and the ground water model
provided with the application and have the following comments.
I) GENERAL
As with all such operations in the South Platt 100 year flood plain, Aggregate
Industries has to be in compliance with all the guidelines and comments of Urban
Flood Drainage Control.
II) EXHIBIT "D"MINING PLAN
A) The operator states," the West Fill area will be graded not less than 2%
and not greater than 25% .The fill area will not infringe Bartner or
Brighton Ditch. Prescriptive, or legal easemenU right of way. The operator
will provide adequate erosion control easements to insure protection of the
Ditches ". What are the erosion control measures that the operator will
implement? Please discuss in detail if erosion control structures are going
to be constructed, and provide the designs for the structures.
B) Under the mining plan, of Phase I the operator had stated," that under
completion of mining the 15.9 acres of Phase I, to be used as a settling/
wash pond for the processing area". Under the water information sub
section (c), you stated," water from phase 3 initial dewatering operation
and runoff from disturbed areas, piled material and operating surfaces, will
likely be diverted to the settling pond for detention and cleaning.
Dewatering trenches will be located around the perimeter of the current
mining phase 3 or 3. Settling occurs in the trenches, and if necessary
settling ponds are constructed at appoint prior to discharge". Where is
location of the dewatering trenches and probable location of settling pond
or ponds? Please indicate on the mining plan maps location of the
probable structures, or commit to provide the design and location of these
structures and get approval from DMG, prior to implementation. Since the
operator is going to obtain the appropriate dischazge permit from
Office of Office of Colorado
Mined Land Reclamation Active and Inactive Mines Geological Survey