APPCOR10990

• Permit No: C1984062
• IBM Index Class Name: Application Correspondence
• Doc Date: 10/4/1985
• Doc Name: INTERPRETATION OF HYDROLOGIC MONITORING AT MINE 3 FILE C-84-062
• From: MLRD
• To: COLO YAMPA COAL CO
• Media Type: D
• Archive: No

• • ~ ~~~~~~ I~ III I IIII I II IIIII III
flit nartl D. Lamm
Governor
DEPARTMENT OF NATURAL RESOURCES
Davitl H Getches. Executive Duector
MINED LAND RECLAMATION DI\
DAVID C. SHELTO N, Director
October 4, 1985
Terrell Johnson
Colorado Yampa Coal Co.
29588 County Road 21
Oak Creek, CO 80467
RE: Interpretation of Hydrologic Monitoring at Mine #3
File C-84-062
Dear Mr. Johnson:
Attached is the Division's interpretation and results of the water sampling
that was conducted at the #3 mine on July 29 and 30, 1985. As with an~r
interpretation, you may view the results differently. At the end of this
letter, there are general comments on your monitoring ?ion for your
consideration.
1. Sample CYCC38507A is a partial parameter list surface water sample ta<=n
on upstream Foidel Creek at site 09243900. The ML.D sample had a pH and
EC of 8.17 and 1,970 umhos, respectively. This compares ro aata
collected in July 1984 by the operator of pH = 8.6 and ..C = 1,650 and in
August 1984 of pH - 8.3 and EC = 2,200. The samcies appear to be
consistent in relative composition and concentrations.
2. Sample CYCC38507B is a full parameter list sample of bedrock overburden
aquifer. The MLRD sample had an EC of 1320 umhos and iDS of 1,080 mg/l.
Since 1980, the operator has reported EC values from 1,000 tc 1,390 umhos
and TPS values from 804 mg/1 to 1,168 mg/1. The major discrepancy
between the MLRD and CYCC sample is in the EC. 'd'nen '1L.P0 in itially
sampled the well, the EC was 1,080 but increased to 1,320 as the Nell Nas
bailed to bring in fresh ground water. The fact tha~_ C(CC does not hail
wells may er.plain this discrepancy.
3. Sample CYCC38507C is a full list groundwater sample Oaken at the Middle
Creek Pit spoils well. The spoil water quality was high in sulfates at
2,510 mg/l, high in dissolved solids at 3,190 mg,l and~has ,i nigh C at
3,960 umhos. The mine #3 application predicted a spoil water quality of
2,200 mg/1 TDS and an EC of 3,000 umhos, basea on leach tests. The
sample results show that the spoils water quality is ar_tualiy worse than
was predicted. No data has been supplied to MLRD by C'(CC on this well to
date to enable a comparison.
a23 Centennial Building, tat 3 Sherman Street Denver, Colorado 90203 Tel. [phone]