REP37198

• Permit No: C1982056
• IBM Index Class Name: Report
• Doc Date: 9/18/1998
• Doc Name: 1997 AHR Review Letter ‎(Memo)‎
• From: Kent Gorham
• To: Janet Binns
• Annual Report Year: 1997
• Permit Index Doc Type: HYDROLOGY REPORT
• Media Type: D
• Archive: No

III IIIIIIIIIIIIIIII STATE OF COLORADO
DIVISION OF MINERALS AND GEOLOGY
,!"- Department of Natural Resources
9 313 Sherman SL, Raom 215 J
y
~~

Denver, Colorado 80203 ~
~~~~
~

Phone: [phone] I I
FAX: [phone]
DEPARTNIEIVT OF
NATURAL
RESOURCES
Roy Romer
Governor
lames S Lochhead
Executive Director
Michael B. Long
Division Director
Memorandum
DATE: September 18, 1998
70: Janet Binns /P~,~r
FROM: Kent Gorham V ter
RE: 1997 Annual Hydrology Report, Foidel Creek Mine,
#G82-056
CC: Dan Hernandez
I have completed review of the 1997 Annual Hydrology Report for the Foidel Creek
Mine. Overall, the operator did an outstanding job of completing the hydrologic
monitoring requirements as per the approved plan. The report was also well organized,
clear, and concise. Graphs, tables and maps were well done and accurate. A report of
this quality should be the standard for all Colorado coal mines.
The mine is affecting ground water levels in the Wadge overburden due to undermining
and subsidence. Water levels in FBR-1 la have declined over 150 feet in the last three
years. Water levels in well 006-82-74C appear to be recovering slightly, likely due to the
completion of mining in the immediate vicinity. Water quality also indicates evidence of
the movement of natural groundwater to the well bore, as TDS levels have gone from
3300 mg/1 to near 1000 mg/1. We1191 M006 also shows a decline of neazly 150 feet since
1992, with a quality that is fairly well represented by 900 mg/1 TDS. We1193M001
shows a steady decline since April of 1996, likely due to mining and subsidence
downgradient. No impacts beyond that predicted in the PHC are evident.
Alluvial well data show seasonal, yet stable water levels and quality remains primarily
dictated by the quality of the adjacent stream. Foidel Creek alluvial water quality
downstream of the mine facility shows a steady increase in EC, from 1400 umhos/cm in