2004-10-26_REVISION - M1978116

• Permit No: M1978116
• IBM Index Class Name: Revision
• Doc Date: 10/26/2004
• Doc Name: Second Adequacy Review
• From: DMG
• To: Cotter Corporation
• Type & Sequence: AM1
• Media Type: D
• Archive: No

STATE OF COLORADO
DIVISION OF MINERALS AND GEOLOGY
Department of Natural Resources
1313 Sherman St., Room 215
Denver, Colorado 80203
Phone: [phone]
PAX: [phone]
October 26, 2004'/
Mr. Dick White
Cotter Corporation `~
28151 DD Road
Nucla, Colorado 81424
RE: SM-18 Mine,, P rere mit No
Dear Mr. White:
COLORADO
DIVISION OF
MIN 6RALS
GEOLOGY
REC LAMgTION•MIN ING
UFETY•Sq ENCE
BIII Owens
Governor
Russell George
Executive Director
Ronald W. Cottony
Division Director
Natural Resource Trustee
M-7978-116, Amendment No. 1 Second Adequacy Review /
The Division of Minerals and Geology (DMG) completed review of Cotter Corporation's (Cotter) response
to the preliminary adequacy review of your application for Amendment No. 1 (AM-01) to Permit No. M-
1978-1 18 for the SM-18 Mine. The application cannot be approved until the following remaining issues
are adequately addressed. Please submit a response to the following issues as soon as possible, but na
later than November 4, 2004 so the decision due date set for November 8, 2004 can be met. If you
cannot respond by November 4, 2004 please submit a written request for extension of the decision date.
If your response, or an extension request, are not received by November 4, 2004 this application may be
denied.
ADEQUACY ISSUES
1. Response acceptable.
2. Response acceptable.
3. Response acceptable.
4. Please provide detailed drainage control plans for the pad area. It appears that the plan should
direct drainage from this area away from the portal bench, that has limited space for allowing
puddling to occur (no discharge). Additionally, the plans must demonstrate that the riprap is
sized appropriately for the peak discharges to be experienced during the 10 yr. / 24 hr. event
(during mining). The drainage control features have been demonstrated to be adequately sized
for the 10 year 24 hour precipitation event during the operation of the mine. Please
demonstrate that these features lupland diversions and riprap sizing/placement) will adequately
handle the 100 year event after reclamation. The plan must demonstrate that all mining
features will remain stable and that discharge points will not cause erosion due to the
concentrated velocities either during or after mining. Please also submit cross-sectional or
other detail drawing of the waste rock dump catchment ponds, demonstrating adequate size to
hold the stormwater volumes specified in Appendix B of Cotter's preliminary adequacy review
response.
5. Response acceptable.
Ollie of Office of Colorado
Mined Land Reclamation Active and Inactive Mines Geological Survey