REV02437

• Permit No: C1980007
• IBM Index Class Name: Revision
• Doc Date: 8/29/1994
• Doc Name: WEST ELK MINE TR 69 LONE PINE GULCH FAN PORTAL SECOND SUPPLEMENTAL SUBMITTAL PN C-80-007
• From: DMG
• To: CHRISTINE JOHNSTON
• Type & Sequence: MR134
• Media Type: D
• Archive: No

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STATE OF COLORADO
DIVISION OF MINERALS AND GEOLOGY
oc; cow
Depanment o(Natural Resources ~~;
„
~
1313 Sherman St., Room 215 r
~
Denver, CO 80203 .
Phone: [phone] rear
FAX: [phone]
er
DATE: August 29, 1994 Gove ho
T0. Christine Johnston
FROM: Jim Pendleton `~~
RE. West Elk MitCp~y.R'69, Lone Pine Gulch Fan Portal -
Second Supplemental Submittal (Permit No= C-80-007}
Michael8 Lonp
Dieision DireUOr
I have completed a revievr of the additional documentation submitted by Mountain
Coal Company {MCC} in support of their technical revision for the back door fan
portal in Lone Pine Gulch. In response to my earlier request, MCC submitted copies
of the strength test data and the critical stability analyses. Based upon this
additional documentation I recommend approval of the proposed technical revision
with the following conditions.
{1} The surface drainage at both the portal bench subsoil storage area and the
underground rock waste storage area should be carefully constructed and
maintained in order to ensure that these piles will remain as dry as possible.
(2) Sur~dey monitoring stations should be established, not only on the north-facing
slope of the subsoil storage area, as proposed by MCC, but in all the potentially
affected sloping areas. Monitoring stations should be established above and below
the fan portal bench; above, below and on the subsoil storage bench; and above,
below and on the topsoil stock pile. The monitoring stations above and below the
disturbed areas should be established prior to the excavation and construction to
ensure detection of any mo~dement during the construction.
Assuming the imposition of these conditions, I recommend approval of MCC's
amended technical revision No. 69, for construction of the Lone Pine Gulch fan
portal and related facilities. I would appreciate your keeping me appraised of
progress at the site. I will attempt to visit the site this fall.
cc: Dave Berry
Doc: M:/COAL,'JAP/MTG 1TR69.APR