1996-01-26_GENERAL DOCUMENTS - C1980007

• Permit No: C1980007
• IBM Index Class Name: General Documents
• Doc Date: 1/26/1996
• Doc Name: Proposed Decision & Findings of Compliance for PR6
• From: Apache Rocks Lease
• Permit Index Doc Type: FINDINGS
• Media Type: D
• Archive: No

around the West Elk Mine is confined to shallow wells in the alluvium and Rollins Sandstone
of the North Fork of the Gunnison River and its tributaries.
The West Elk Mine's experience in mining the F and B Seams indicates that ground water
inflows are associated with fractures near the subcrop and are seasonal. Evidence suggests
that ground water movement is controlled largely by fracture patterns and topography.
There are seven categories of potential aquifers that occur in the Somerset Coal Field. These
are: 1) the alluvial and terrace deposits associated with the North Fork of the Gunnison
River; 2) the localized, shallow alluvium along creeks tributary to the North Fork; 3) the
discontinuous, lenticular and laminar sandstones of the Mesaverde Formation; 4) the Rollins
Sandstone; 5) the coal seams; 6) shallow colluvial surficial deposits; and 7) fracture zones in
bedrock.
The most continuous sandstone aquifers of any significance in the region are the Rollins
Sandstone and the massive sandstone separating the upper and lower Coal members of the
Mesaverde Formation. However, the latter massive sandstone produces very little water, as
evidenced by the dryness of the Bear Mine and the lack of springs associated with this unit.
The Mesaverde Formation tends to be dry, or the rock units are of such a low permeability,
they yield insufficient water for sustained use or mine discharge. The sandstones are
lenticular and discontinuous and are usually highly cemented.
A description of the surface water system can be found in Section 2.04.7 of the permit
application. Supporting information is contained in Map 34, which illustrates the drainages
associated with the WEM coal lease area, Map 37, which delineates the location of all known
springs on the coal lease area, and Map 36, which shows the reservoirs and irrigation ditches
associated with the Minnesota Creek Basin.
A description of the surface water occurrence and mining impacts on adjacent areas can be
found in the "Probable Hydrologic Consequences of Mining" section of this document, and
the "Cumulative Hydrologic Impact Study" document for this mine area.
All of the streams draining the West Elk Mine permit area are tributaries to the North Fork
of the Gunnison River. Sylvester Gulch, Lone Pine Gulch, and Gabble Gulch are ephemeral
streams draining the northern portion of the lease area. Minnesota Creek and its tributaries,
Horse Creek, South Prong, Lick Creek, Dry Fork, and East Fork, drain the southern portion
of the coal lease area. Minnesota Creek enters the North Fork of the Gunnison River near
Paonia. The overall drainage exhibits a dendritic drainage pattern with steep channels.
Horse Creek and South Prong of the East Fork of Minnesota Creek are perennial streams,
while Lick Creek, Upper Dry Fork, Sylvester Gulch and Gribble Gulch are ephemeral
streams. Minnesota Reservoir controls much of the flow in the lower Dry Fork of
Minnesota Creek, and Beaver Reservoir controls the flow in the East Fork of Minnesota
Creek. Lone Pine Gulch has no evidence of recent flow; therefore, no gaging station has
been constructed. Even when all of the six gaged watersheds were found to be flowing,
Lone Pine Gulch showed no flow or evidence of flow.
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