2004-12-07_PERMIT FILE - C1984063

• Permit No: C1984063
• IBM Index Class Name: Permit File
• Doc Date: 12/7/2004
• Section_Exhibit Name: Rule 2.04 Environmental Resources
• Media Type: D
• Archive: No

• to greater depths are indicative of a recharge area. The
outcrop areas for the formations along the Hogback and areas
overlain by saturated alluvium are the probable sources for
recharge.
Ground Water - Alluvial Aquifers. Alluvial ground water
exists primarily in the area south of the Grand HogbacK and
permit area along the Colorado River. The Colorado River
has extensive fluvial/glaciofluvial sand and gravel deposits
along its course. This material Yields significant amounts
(5-100 gpm) of ground water and may produce as much as 1,000
gpm. The alluvial aquifer was deposited on bedrock
sediments of the Wasatch Formation and Mesa Verde Group.
Thickness of the material is as much as 87 feet along the
Colorado River, and may be as much as 180 feet on higher
terraces north of Interstate 70. Ground water contained in
these deposits provides domestic and livestock supplies from
26 wells located in the area south of the permit area (see
Table 2: Ground Water Sampling Point Specifications).
Reported water yields range from 2 - SO gpm (Figure 8: Water
Well Locations and Statistics).
Minor alluvial aquifer potential exists along the Elk CreeK
drainage north of the Hogback. the alluvium is perched on
Mancos Shale and is isolated from the coal seams by being
• stratigraphically above the Mancos. Two wells reportedly
produce from this aquifer and are shown on Figure 8: Water
Well Location and Statistics and Table 3: Aquifer
Characteristics.
The geologic relationships between the various strata of the
permit and adjacent areas are shown in Figure 3: Bedrock
Geology Map and Cross Section A-A' and Figure 4: Geologic
Cross Section A-A'. The strata locations demonstrate that
the aquifers and coal seams to be mined are isolated by
several thousand feet of semi-impervious to impervious
shales, siltstones and clays. No communication between the
seams and the alluvial aquifer will occur. Consequently, no
impact to existing and future water supplies will result due
to mining activities.
Water levels reported for wells tapping the alluvial
aquifers are given in Table 4: Potentiometric Measurements
of Ground Water Sampling Points. Since no elevation data is
available for these wells, no accurate water.
table/piezometric surfaces are possible. Depth to water in
these wells ranges from 0 to 110 feet. Figure 8 (Water Well
Locations and Statistics) gives a representation of depth to
water from the alluvial wells in the area. Figure 4
(Geologic Cross Section A-A') illustrates the geologic

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