APPCOR12823

• Permit No: C1996084
• IBM Index Class Name: Application Correspondence
• Doc Date: 8/1/1997
• Doc Name: LORENCITO MINE ADEQUACY RESPONSES C-96-084
• From: GREYSTONE
• To: DMG
• Media Type: D
• Archive: No

Environrnenta! Planners, Scientists and Engineers
Mr. Ken[ Gorham
Colorado Division of Minerals and Geology
1313 Sherman Room 215
Denver, CO 80203
Subject: Lorencito Mine Adequacy Responses, C-96-084
Dear Mr. Gorham:
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LCC would like to tie up remaining loose ends on outstanding adequacy issues to date.
Questions 73 and 117 from the July 22, 1973 letter were left unanswered in the 7/29/97
submittal. We received additional questions from Janet Binns on July 25, 1997, which are also
answered.
68. Upon further review of the permit application, it appeared that the description of the area
proposed for a variance from contemporaneous reclamation was inaccurately
characterized on page 2.05-3. The length of [he initial cut has been modified to
correspond to the map.
73. The underground development waste pile is going to be placed in the initial cut area for
which a contemporaneous reclamation waiver is requested. This area is bounded by a
highwall on one side, and spoil material at its base. The pile will be below the normal
ground surface and will be backfilled with spoil following mining in Year 6. The area
is at the top of the pre-mine ridge, and very little watershed would contribute water to
the area. As a consequence, designs for upland diversions are moot. The Professional
Engineer certification has been provided for Maps 2.05-3-1 and 2.05.4-1 which show the
location of the underground development waste pile, as well as on Figure 2.05.3-18, the
cross section. A stability analysis is provided which includes general information on the
dry density of the coal waste, as well as a minimum safety factor.
117. LCC has modified the inserts for the permit application binders to reflect that the Jeff
Canyon Surface Mine is a mountaintop removal operation. In addition, a change has
been made to page 2.05-5 to reflect that this is a mountaintop removal operation.
190. LCC accepts a stipulation on future determination of the Woody Plant Density standard.
&191.
195. We have revised the spelling of Sporobolus airoides on page 2.05-66.
Topsoil salvage information on page 2.05-33 and Table 2.05.3-2 have been modified to reflect
salvage on slopes up to 50`7.
The topsoil swell factor of 20% was a conservative general approximation. The CDMG Draft
Reclamation Cost Estimating Manual included a table which compared bank and loose yardage
associated with soil-type materials. An excerpt follows:
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