REP35241

• Permit No: C1980001
• IBM Index Class Name: Report
• Doc Date: 7/26/2000
• Doc Name: EDNA MINE PN C-1980-001 1999 ANNUAL HYDROLOGY REPORT REVIEW
• From: DMG
• To: PITTSBURGH & MIDWAY COAL CO
• Permit Index Doc Type: HYDROLOGY REPORT
• Media Type: D
• Archive: No

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999
DIVISION OF MINERALS AND GEOLOGY
Depacmenl of Natural Rescurces
_ iher,nan :; . Farm `1 i
Denver, Colorado 80203
Phone: [phone]
FAX: [phone]
July 26, 2000
STATE OF COLORADO
~~
DIVISION OF
MINE[tALS
GEOLOGY
R E C L A M A T I O N
MINING•SAFETY
Mr. Brian Gontazek e,,, owe^s
Pittsburgh & Midway Coal Company cover^nr
PO. Box 6518 Greg E Walther
Englewood, CO 80155-6518 E~ecwive D~reaor
Michael B Long
Drvisicn D~recto~
RE: Edna Mine, Permit No. C-1980-001
1999 Annual Hydrology Report Review
Dear Mr. Gontarek:
The Division of Minerals and Geology (DMG) has reviewed your 1999 Annual Hydrology
Report (AHR). The frequency of data collection is in compliance with the approved
monitoring plan contained in the permit application document. The DMG has the
following comments concerning the 1999 AHR
1. The DMG notes that the CDPS sulfate limitation was exceeded for discharges to
Trout Creek on four occasions during 1999. These exceedances occurred in July, August,
and December at DMP 004 and in December at DMP 007.
Based on review of data from surface water monitoring sites TR-A, TR-B, TR-C,
and TR-D, the numeric standard for sulfate for the mainstem of Trout Creek (Segment 13c
of the Yampa River Sub-basin) was not exceeded on any occasion during 1999. 'T'herefore,
there are no specific material damage issues to be addressed by the Division at this time as a
result of the CDPS sulfate criteria exceedances.
There is a significant increase in sulfate concentration from the upstream monitoring
location on Trout Creek (TR-A) to the downstream monitoring point (TR-D). The highest
concentration reported for TR-D in 1999 is 660 mg/1 which is within the PHC prediction.
The PHC prediction contained in the PAP states that sulfate concentrations in Trout Creek
might be expected to reach an upper limit of approximately 842 mg/1 at some time during
the mining and post-mining era at the EDNA Mine.
Please note that DMP 007 is not shown on the Water Monitoring Location Map (Exhibit
4.6-26).
2. On page 9 of the 1999 AHIt, P&M states that "although elevated TDS
concentrations have moved downstream in conjunction with mining and reclamation
activities, all values for TDS aze consistent with the probable hydrologic consequences
projections". It is evident that there has been a significant increase in TDS concentration