2010-10-22_REVISION - M2008017 ‎(4)‎

• Permit No: M2008017
• IBM Index Class Name: REVISION
• Doc Date: 10/22/2010
• Doc Name: TR-01 Adequacy Review Comment Responses
• From: J&T Consulting, Inc.
• To: DRMS
• Type & Sequence: TR1
• Email Name: MAC
• Media Type: D
• Archive: No

Broken Arrow Investments, LLC Derr Pit, File No. M-2008-017, TR-01 Adequacy Review Comment Responses
10/21/10
-2-
Response:
The methods of mining will remain similar to the original mining plan with the
addition of a drag line to wet mine materials. Below is an updated description
of the methods of mining including equipment.
The deposit will be wet mined initially and then dry mined after a slurry wall is
constructed around the perimeter of the mining area after wet mining to the
interim mining limit in Phases 2, 3, and 4 as shown on the attached Exhibit C
Mining Plan Map. Design specifications for the slurry wall and quality control
procedures used during construction will ensure that the reclaimed reservoir
meets State Engineer's Office (SEO) performance standards. Dewatering
trenches will be excavated around the perimeter of each mining area in
Phases 2-5 prior to mining operations commencing and after installation of
the slurry wall.
The equipment and facilities may include, but are not limited to the following:
Processinq Equipment
Screens, crusher, conveyors, stackers, and other miscellaneous processing
equipment. (The plant will be a portable setup.)
Earth Moving Equipment
Dozers, loaders, scrapers, drag line, excavators, and compactors will be used
for mining and earth moving operations.
Miscellaneous Equipment
Dewatering pumps, electrical trailer, generator trailer, small portable
generators and watering trucks will be used as needed.
As mining progresses, topsoil and overburden will be stripped with scrapers
to expose the aggregate product below. All soil and overburden material will
be used on-site for reclamation; so long-term stockpiling of these materials is
not anticipated. Overburden stockpiles will be located within the proposed
mining area and placed so that they do not impede potential floodwaters. The
stockpiles will be placed outside the floodplain where possible.
Mining of the aggregate will progress down to the underlying bedrock. Since
reclamation will occur concurrently with mining, it is not anticipated that
bedrock material will be stockpiled long-term prior to use if it is used in the
reclamation slopes.
During wet mining the mining face will be near vertical, during dry mining after
the installation of the slurry wall and at the completion of reclamation, the
mining face will have a 3H:1 V slope. The aggregate material will be
temporarily stockpiled near the portable plant site outside the floodplain
where possible during wet mining. After installation of the slurry wall,
W 1 1400 W 122" d Avenue - Suite 120 • Westminster CO 80234 • Ph: 303-457-0735 • Fax: [phone]