ENFORCE29640

• Permit No: M1988112
• IBM Index Class Name: Enforcement
• Doc Date: 12/15/1997
• Doc Name: FINAL ABATEMENT OF NOV M-92-026 SAN LUIS PROJECT PN M-88-112
• From: DMG
• To: BRUCE HUMPHRIES
• Violation No.: MV1992026
• Media Type: D
• Archive: No

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STATE OF
DIVISION OF MINERALS AND GEOLOGY
Dcpanmenl of Natural Resources
1 713 Sherman 51., Room 215
Denver, Colorado 60203
Phune: 0031 866]567
FA%: (3071 83 2-61 06
December l5, 1997
To: H. Bruce Humphries, James Stevens
From: James Dillie
Re: Final Abatement of NOV M-92-026, San Luis Project, M-88-112
II~
DEPARTMENT OF
NATURAL
RESOURCES
Roy Romer
Governor
lames 5. lochhead
Executive Duecmr
MichaelB Lung
Dwnion Director
BMRI was issued a NOV (M-92-026) in April, 1992. The Board assessed a civil pena~ry (which was
paid) and ordered 12 violation abatement requirements. In addition, the Board issued ur interim Board
Orders; two in June, 1992 and two in July, 1992. Following is a status and progress report of the
abatement requirements:
Increased tailings area security: Status; Tailings area security was discontinued when WAD
cyanide levels dropped below 10 ppm (and pH levels were below 9.0). Tailings area security
has not been re-initiated because WAD cyanide levels have remained below l0 ppm and pH
levels have never exceeded 9.0 since security was discontinued
2. Assessment of environmental impact: Status; Satisfied. BMRI submitted an $cceptable report
April 13, 1992.
3. Accelerated frequency of environmental monitoring: Status; Implemented. iii-weekly
monitoring continues at the tailings and collection ponds.
4. Tailings cyanide detoxification: Status; Completed. BMRI utilized Cytox, Hydrogen Peroxide
and the Inco process to reduce cyanide levels in the tailings and collection ponds. As of
November 5, 1997, WAD cyanide levels were 0.123 ppm in the tailings pond and 0.029 ppm
in the collection pond.
5. Leak detection system effluent containment: Status; Implemented. BMRI cot•;mtitted to repair
the primary liner at the collection pond if a leak is detected. To date, no IeaIF has been
detected.
6. Cyanide detection, interception, containment and remedial treatment: Status; Completed.
BMR[ submitted TR-08, TR-09 and TR-IS to abate this requirement.
Modification of ore processing methodology: Status; Completed. BMRI initiated the Inco
process in October, 1992.
8. Modification of tailings area reclamation plan: Status; Satisfied. The Board end Division was
concerned that the introduction of high cyanide concentrations into [he tailings impoundment
would modify the tailings chemical constituency which may require a modi cation of the
reclamation plan for the tailings. Therefore, BMRI was required to submit a reclamation