2008-04-03_APPLICATION CORRESPONDENCE - C2006085 ‎(2)‎

• Permit No: C2006085
• IBM Index Class Name: APPLICATION CORRESPONDENCE
• Doc Date: 4/3/2008
• Doc Name: Response to Comment Letter
• From: DRMS
• To: Fremont County Commissioners
• Email Name: DIH
• Media Type: D
• Archive: No

STATE OF COLORADO
DIVISION OF RECLAMATION, MINING AND SAFETY
Department of Natural Resources
1313 Sherman St., Room 215
Denver, Colorado 80203
Phone: [phone]
FAX: [phone]
COLORADO
DIVISION O F
RECLAMATION
MINING
- ~t-
SAFETY
Apri13, 2008 Bill Ritter, lr.
Governor
Mike Stiehl Harris D. Sherman
Fremont County Commissioners Executive Director
Room 105
615 Macon Ave. Ronald W. Cattany
, Division Director
Canon City, Colorado 81212 Natural Resource Trustee
Re: Northfield Mine (Permit No. C-2006-085)
Proposed Decision Comments
Dear Mr. Stiehl:
The Division of Reclamation, Mining and Safety received your comments with attachments via email on April 3,
2008 regarding the proposed decision to approve with conditions an application for a permit to conduct coal
mining operations at the Northfield Mine.
After review of your comments, it was very apparent that you did considerable research and review regarding the
location of existing underground coal mine workings as they relate to the Cotter Mill. After review of your
comments, the Division was able to locate a map depicting the plume of ground water contamination emanating
from the Cotter facilities. Generally, this plume begins at a tailings pond along Sand Creek in the north portion of
the SE1/4 Section 9, T19S R70W of the 6th Principal Meridian (Lincoln Park Citizen's Update, Vol. 15, No. 1 Dec.
2006). This plume appears to be moving in a northeasterly direction, generally following Sand Creek into the
Lincoln Park neighborhood and towards the Arkansas River. A similar but slightly different north/northwesterly
groundwater gradient for the Northfield mine was confirmed through information provided in Exhibit K of the
Northfield permit application.
The nearest planned mining at Northfield would occur in the Ocean Wave coal seam located almost two miles due
east of the source of the Cotter Mill contamination. Given the groundwater gradients as presently understood, it is
unlikely that an Cotter Mill contamination would occur, or could develop, anywhere in close proximity to the
planned Northfield workings. However, your point regarding the flooding of the Chandler workings and the fact
that portions of the Chandler workings apparently lie under the Cotter site and also over and adjacent to the
planned Northfield workings is well taken. Even with approximately 250 feet of interburden between the Chandler
workings and the Ocean Wave seam, it is possible that some inflow from the Chandler workings could occur due
to mining and subsequent subsidence if the workings are indeed flooded at that location.
The Northfield permit application does in fact speak to possible mine inflows due to mining and estimates a range
of potential inflow from near zero to about 280 gallons per minute. Please also be aware that discharge of mine
water was considered in the design of the sediment pond as well as consumptive use of water that may enter the
workings and leave on the coal product or through the mine ventilation system. Mine water discharge from the
pond is regulated and permitted through the Water Quality Control Division via the Colorado Discharge Permit
System. The hydrologic monitoring plan required by our Division also considered the potential for mine water
discharge and the monitoring plan was developed accordingly.
In addition, the Mine Safety and Health Administration (MSHA) closely monitors the inflow of water to the mine,
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