REP26901

• Permit No: C1980005
• IBM Index Class Name: Report
• Doc Date: 4/8/1986
• Doc Name: SENECA II 1985 ANNUAL HYDROLOGIC REPORT FILE C-80-005
• From: MLRD
• To: STEVE RENNER
• Permit Index Doc Type: HYDROLOGY REPORT
• Media Type: D
• Archive: No

Richard D. Lamm
Governor
DATE
TO
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DEPARTMENT OF NATURAL RESOURCES
Dared H. Getcnes, Executive Director
MINED LAND RECLAMATION DI\
DAVIDC. SHELTON, Director
April 1, 1986
Seneca II File
FROM: Steve Renner
RE: 1985 ANNUAL HYDROLOGY REPORT: GROUND WATER REVIEW
Enclosed are my comments after reviewing the ground water section (including
spoil springs) of the 1985 AHR.
In general, water levels at most wells decreased during the 1985 reporting
period. This is due to a general decrease in precipitation at the mine site.
Note, however, that even though precipitation decreased, it was still an above
average water year. Runoff in 1985 was about one month earlier than usual,
the peak being somewhat less then 1984.
Most wells exhibit a decrease in head due to the lower amount of available
water. Also, recorded was the seasonal variability of water levels,
especially in the near surface completions.
Water quality has not significantly changed in 1985, however, some wells do
exhibit elevated TDS levels. This is probably due to a high concentration of
"salts" in the surrounding strata, which is less diluted than in previously
high water years.
The well of most interest, GW-546, is completed in the alluvium of the unnamed
ephemeral tributary (aka Cow Camp Creek) to Fish Creek, below the 004 pond.
This well exhibited the normal seasonal fluctuations expected in an alluvial
completion. The water in this well is a magnesium/sulfate type, and exhibits
an average TDS concentration of 2444 mg/1 (versus 2068 mg/1 previous to
mining, and 1529 mg/1 at the 004 pond discharge). This is apparently due to
natural conditions of the alluvial material rather than being a direct result
of mining activities (004 pond should intercept surface as well as underflow
from the backfilled Wadge Pit).
The Lennox-Wadge interburden completion GW-S44P2, as well as Lennox overburden
completion GW-S44P1, and Wadge Coal completion GW-S44 exhibit decreasing head
as mining progresses toward these wells.
In the Wolf Creek mining area, the following wells have been losing head as
mining progresses: GW-S360, (Wolf Creek overburden/Wadge underburden
completion. Wells GW-S8 and GW-S8P1, also completed as GW-S360, have lost
head, it is postulated that this may be due to Wadge mining operations,
continued careful monitoring at these sites, as well as more thought, is
warranted at this time. .
423 Centennial Building, 1313 Sherman Street Denver, Colorado 80203 Tel. [phone]