APPCOR11820

• Permit No: C1981034
• IBM Index Class Name: Application Correspondence
• Doc Date: 10/8/1982
• Doc Name: GRAND MESA GROUND WATER FINDINGS
• From: MLR
• To: DAN MATHEWS
• Media Type: D
• Archive: No

•- i
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STATE OF COLORADO RICHARD D. LAMM, Gavem n~
• III IIIIIIIIIIIII III
DEPARTMENT OF NATURAL RESOURCES 999
D. Monte Pascoe, Executive Director
MIlVED LAND RECLAMATION
423 Centennial Building, 1313 Sherman Street
Denver, Colorado 80203 Tel. [phone]
David C. Shelton
Director
DATE: October 8, 1982
TO: Dan Mathews
FROM: David Craig ~~ J
RE: Grand Mesa Ground Wate ings
GROUND WRTER
Description of the Environment
There are four geologic units in the vicinity of the proposed mine area
which could potentially be called aquifers. They are, in ascending order,
the Rollins Sandstone, the D coal seam, the E coal seam, and the
unconsolidated glacial/alluvial material which mantles much of the surface.
Water wells have been completed in all of these aquifers in the vicinity
of the mine. The most used aquifer in the area is the unconsolidated
glacial/alluvial geologic unit. Generally, the bedrock aquifers do not
yeild sufficient quantities of potable water for economical large-scale
development. The applicant's description of ground water is contained in
Sections 2.04.5(1) and 2.04.7 of the permit application, and in the 1982
addendum (Kimball, et al., 1982). The four potential aquifers are
discussed in greater detail below.
The Rollins Sandstone, of the Iles Formation, exists about 150 feet below
the lowest proposed mine workings (D seam). It is unlikely that the
proposed mining operations will impact the aquifer. The strata separating
the sandstone from the mine workings consist of shales, siltstones, coals,
and laterally discontinuous sandstones. These units should provide a
sufficient barrier so as to prevent vertical hydrologic communication between
the aquifer and the mine workings.
Therefore, the Rollins Sandstone aquifer will not be discussed further in
this document.