REP46745

• Permit No: C1982057
• IBM Index Class Name: Report
• Doc Date: 8/5/1987
• Doc Name: SENECA II-W ANNUAL HYDROLOGY REPORT C-82-057
• 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, Governor
DEPARTMENT OF NATURAL RESOURCES
MINED LAND RECLAMATION DIVISION
DAVID C. SHELTON, Director
August 5, 1987
Mr. Jim Lunan
Peabody Coal Company
1300 South Yale Avenue
Flagstaff, Arizona 86001
Re: Seneca II-W Annual Hydrologic Report (File No, C-82-057)
Dear Mr. Lunan:
The Division has completed its review of the first Seneca II-W Annual
Hydrologic Report (AHR). This report contains data for the period of
August, 1980 through September, 1986. All future annual hydrologic reports
will cover the period of one water year, and are scheduled to be submitted to
the Division by February 28 of the following calendar year (Stipulation No. 5).
Technical Revision No. 1 to the Seneca II-W permit (approved May 13, 7987)
revised a number of monitoring site locations and, in some cases, the
frequency of monitoring some of these sites. The revised hydrologic
monitoring program has been incorporated into the approved permit document as
Appendix 7-1 (revised May 7, 1987). The hydrologic monitoring program
outlined in the currently approved Appendix 7-1 supersedes the hydrologic
monitoring proposal summarized in the Annual Hydrologic Report.
The Division requests that Peabody Coal Company respond to the following
concerns which were raised during the AHR review.
1, The report states that streamflow is perennial for stations SG4, FG1 and
SG5 and not intermittent as originally stated in the permit. As baseline
data was collected during a period of low streamflow, and subsequent data
have been collected in a high flow period, is this modification of the
description of streamflow regime based on the more recent data, or does
it include a consideration of the previous data as well?
2, On page 91, the report states the mean TDS value is 701 mg/L at FG1.
This value 1s inconsistent with Table 27 which indicates the mean is 927
mg/L. Peabody Coal Company should clarify which value is the correct
mean TDS concentration at Station FG1.
423 Centennial Building, 1313 Sherman Street Denver, Colorado 80203-2273 Tel. [phone]