2010-10-12_REVISION - M1980047

• Permit No: M1980047
• IBM Index Class Name: REVISION
• Doc Date: 10/12/2010
• Doc Name: Preliminary Adequacy Review
• From: DRMS
• To: ExxonMobil
• Type & Sequence: TR13
• Email Name: THM
• Media Type: D
• Archive: No

w, sA? , 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]
October 12, 2010
Mr. Tom L. Adams
ExxonMobil v,'-
P.O. Box 2567
Houston, TX 77252-2567
Re: ExxonMobil, Colony Oil Shale Ject, Permit No.
Technical Revision, TR-13
Dear Mr. Adams:
Loretta E. Pinecla
Director
M-1980-047, Preliminary Adequacy Review,
The Division of Reclamation, Mining and Safety reviewed the ExxonMobil request for a 112 Hard Rock, Metal
Technical Revision for the Colony Oil Shale Project, File No. M-1980-047. A few minor issues must be addressed
before the revision can be approved.
1. Please provide an estimate of the volume of water that will be captured and discharged from the four (4) to
eight (8) proposed A-Groove drainage holes.
2. Monitoring of the A-Groove aquifer immediately above the Mahogany zone is not included in the
monitoring program. The operator must protect. and monitor aquifers above and below the
mining/experiment interval. Therefore an A-Groove monitoring well(s) shall be included in the monitoring
program.
The section titled Ground and Surface Water Monitoring does not provide enough information about the
proposed ground water monitoring program. Please provide all required information described in Rule
3.1.7(7)(b) regarding the proposed groundwater monitoring program.
4. The proposed wellbore abandonment for non-cased drain holes is stated to be "as-is". The Division requires
all holes, cased or not, to be plugged and abandoned in accordance with the requirements set by the State of
Colorado Office of the State Engineer. Specifically, the operator shall follow the requirements of Rule
16.2.1 in the Rules and Regulations for Water Well Construction.
5. Under the section titled Operational Considerations: Water Discharges it states that water used in drilling
the drainage holes will be returned to the surface water system as part of the mine outflow. Please describe
how the drilling water quality will be affected after it has been used for drilling. Will the discharge of
drilling water cause degradation to the existing discharge water quality?
Please respond to the issues listed no later than October 22, 2010 so the decision date of October 28, 2010 can be
met. If a response or an extension to the decision date is not received by October 22, 2010 the technical revision
may be denied.
If you need additional information, please contact me at the Division of Reclamation, Mining and Safety, Grand
Junction Field Office, 101 S. 3rd St., Suite 301, Grand Junction, Colorado 81501, telephone no. [phone].
COLORADO
D IV IS I ON OF
RECLAMATION
MINING
SAFETY
Bill Ritter, Jr.
Governor
James B. Martin
Executive Director
Office of Office of
Mined Land Reclamation Denver • Grand Junction • Durango Active and Inactive Mines