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
10/21110
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stockpiles as well as the portable plant site can be placed below the existing
grade within the mining boundary.
3. The Permittee has committed to maintaining 31-1:1V slopes during
mining. Will the Operator be able to maintain 31-1:1V slopes using wet
mining methods? If so, please describe how this will be accomplished.
Response:
The slope will not be maintained at a 3H:1 V slope during wet mining.
Attached is a slope stability report for the wet mining slope configuration.
Using the results of the slope stability report an interim wet mining limit has
been established as shown on the Exhibit C Mining Plan Map. Once wet
mining is completed, and after the installation of the slurry wall, dry mining
methods will be used and a 3H:1 V mining slope will be utilized and
maintained.
4. The approved Mining Plan states the portable plant will be located at the
base of an actively mined phase. Please describe where the portable
plant will be set up if the site is wet mined.
Response:
The portable plant will be setup on existing grade above the wet mined areas
and outside the interim mining limit as shown on Exhibit C Mining Plan Map.
5. In accordance with Rule 6.4.4(e), please provide a revised time table
describing the relationship between mining and reclamation during
different phases of the mining operation. Also, include the anticipated
point in time in which the slurry wall will be installed.
Response:
Broken Arrow Investments, LLC anticipates mining and reclaiming the Derr
Pit Project site in approximately 15 - 18 years. It is anticipated that Broken
Arrow Investments, LLC would mine to a depth of 3 - 6 feet in Phase 1A-C of
the mining plan encompassing roughly 27.98 acres of the mining limits and
groundwater would not be exposed. Phases 2 - 5 would be mined to a depth
of 70 - 90 feet with each phase being 6.80 - 9.71 acres. However, it is
possible that due to demand fluctuations, mining could progress slower than
anticipated and additional time may be required for mining and reclamation of
the site. After the initial 27.98 acres is mined to a depth of 3 - 6 feet the
mining operations will continue to expand by first wet mining to the interim
mining limit in Phases 2-4, then installing a slurry wall and dry mining the
remaining material in Phases 2-5. At this time the installation of the slurry wall
is anticipated to occur in 3 to 5 years.
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