2010-05-25_REVISION - C1982056 ‎(2)‎

• Permit No: C1982056
• IBM Index Class Name: REVISION
• Doc Date: 5/25/2010
• Doc Name: Letter & Application
• From: Twentymile Coal Company
• To: DRMS
• Type & Sequence: TR73
• Email Name: JDM
• Media Type: D
• Archive: No

Peabody
Twentymile Coal Company

Mr. Jason Musick MAY L' 5 2010
Environmental Protection Specialist
Division ut
Colorado Division of Minerals and Geology ?41r?In xi ! 9J-k rxyan,
a? ?t t??rty
1313 Sherman Street, Room 215
Denver, Colorado 80203
[phone] X 8134
29515 Routt County Road #27
Oak Creek, CO 80467
970.879.3800
May 21, 2010
RE: Twentymile Coal Company - Foidel Creek Mine (Permit No. C-82-056), Technical Revision
(TR10-73) for 19RT Dewatering Installation
Dear Mr. Musick:
Twentymile Coal Company (TCC) requests CDRMS approval of a Technical Revision (TRIO-73) to the
approved Permit, for drilling, completion, operation, and reclamation of a mine dewatering borehole (19-
Right (19RT) Dewatering Well), and associated mine water transfer pipeline and ancillary facilities. The
new dewatering well will be drilled above the 19RT mine workings, near the center of the synclinal basin
in the Wl/2NW'/4SWt/4, Section 9, T5N, R86W. It is designed to allow dewatering, as needed, of the
sealed and abandoned mine workings in the Northern Mining District. The associated pipeline will run
approximately 6,200 feet, from the 19RT Dewatering Well to the 6-Main North (6MN) Mine Water
Handling Facilities, connecting with the existing mine water handling system. The pipeline will be
buried, and surface facilities will be limited to the wellhead and protective casing and a 6,800-foot
overhead power distribution line.
Water from the 19RT Dewatering Well, which will pump accumulated mine inflows from a sump in the
sealed Northern Mining District, will be pumped to the surface by a 320hp high-capacity submersible
pump, at a rate of approximately 550 gpm. The pump discharge will be transferred by the proposed 19RT
Mine Water Transfer Pipeline to connect with the mine water handling system at the 6MN location, where
it can be used to fill the 6MN Mine Water Storage Reservoir, the 6MN Million Gallon Tank, or be routed
back underground for use in active mining areas.
The ancillary facility requirements for the new 19RT Dewatering Well will involve establishment of
Alternative Sediment Controls; stripping and placement in a stockpile of available soil materials from a
pad area; construction of a 100' x 150' (maximum size) facilities pad; installation of the well casing and
protective well cap (8' diameter x 8' deep CMP partially buried pipe with steel cap and lightening
protection); installation of the connecting pipeline and valving; and extension of the power distribution
line from the existing 6MN Substation (includes a pole-mount transformer). The proposed well location
is within 900 feet of existing roads, so drilling activities will involve overland travel, and will be
conducted only as site conditions allow. Given that pipeline inspection/maintenance requirements will be
minimal, no access road will be constructed, and any necessary maintenance access will involve overland.
Pipeline construction will involve placement of construction sediment controls where the pipeline crosses
two ephemeral drainages; grading of available soil material to one side of the 50-foot wide pipeline
corridor; trenching, pipeline placement, backfilling, compaction, and grading of the pipeline disturbance;
and revegetation of affected disturbance areas. Powerline construction will involve minimal disturbance
for pole placement, and, due to the limited period and area of disturbance, will not require soil material
salvage.
G:\Environmental\REVISION\TECH-RV\TR10-73 19RT Dewatering System\TR10-73 19RT Dewatering Installation TL.doc