REP35027

• Permit No: C1980005
• IBM Index Class Name: Report
• Doc Date: 8/28/1987
• Doc Name: SENECA II 1986 ANNUAL HYDROLOGIC REPORT FN C-80-005
• From: MLRD
• To: PEABODY COAL CO
• Permit Index Doc Type: HYDROLOGY REPORT
• Media Type: D
• Archive: No

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STATE OF COLORADO
Roy Romer, Govei
DEPARTMENT OFNATURALRESOURCES
MINED LAND RECLAMATION DIVISION
DAVID C. SNELTON, Dlreetor
August 28, 1987
Mr. Jim Lunan
Peabody Coal Company
1300 South Yale
Flagstaff, Arizona 86001
Re: Seneca II 1986 Annual Hydrologic Report - File No. C-80-005
Oear Mr. Lunan:
The Division has reviewed the 1986 Annual Hydrologic Report (AHR) compiled
from hydrologic data collected at the Seneca II Mine. Peabody Coal Company
Hydrologists are to be commended for the quality of the report.
The Division review of the AHR indicates that Peabody Coal Company is
requesting three revisions to the approved permit document. As these
revisions include requests to reduce monitoring frequencies, a technical
revision should be submitted to the Division. This revision should describe
and justify the requests for monitoring reduction, and include the appropriate
revised pages for the permit document.
A brief comment regarding each revision topic follows:
1) Peabody Coal Company has requested that the monthly monitoring of
Wells GW-S31-A2 and GW-S33 by reduced to semi-annual monitoring of field
parameters and sampling for water quality. Given the water quality
correlations with NPDES 002 and Site SW-S2-2, this request appears
reasonable.
2) A discussion is provided pertaining to the Peabody commitment to verify
the HYMO Model (Appendix G). An explanation is offered that the
comparison is not feasible due to limitations of the model. A request is
made (P. G-1) to revise the permit text to remove this commitment.
The Sedimot II model is currently being used by Peabody for drainage
design. In considering the proposed revision, the option of verifying
the Sedimot II model should be reviewed by Peabody based on the intended
purposes of the commitment. This consideration should be made prior to
the revision submittal.
3) A request is made by Peabody (P. G-7) to modify the previous commitment
for annual surveys of sediment level in the sediment ponds. This
commitment was made at the time of abatement of Notice of Violation
No. C-85-081. The request is to reduce the frequency of surveys to every
five years for Ponds 002 and 003 and every two years for Pond 004.
423 Centennial Building, 1313 Sherman Street Denver, Colorado 80203-2273 Tel. [phone]