GENERAL47047

• Permit No: C1984065
• IBM Index Class Name: General Documents
• Doc Date: 1/1/1985
• Doc Name: PROPOSED DECISION and FINDINGS OF COMPLIANCE
• Permit Index Doc Type: FINDINGS
• Media Type: D
• Archive: No

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IX. Cumulative Hydrologic Impact Study -- Rules 2.05.6(3) and 2.07.6(2)(c)
This Cumulative Hydrologic Impact Study (CHIS) for the hydrologic basin of the
Coal Ridge No. 1 Mine has been prepared by the Colorado Mined Land Reclamation
Division (CMLRD) pursuant to Rule 2.07.6(2)(c). This CHIS assesses the
cumulative hydrologic impacts of all anticipated coal mining operations upon
the Colorado River Valley in the vicinity of the Coal Ridge No. 1 Mine.
Included in this assessment are the Eastside Mine and the proposed Coal Ridge
No. 1 Mine. These mines are both located along, or in close proximity to, the
Colorado River. There are no other. mines located in the general area, and no
other mines with impacts that have the potential to cumulatively add to the
effects of the Eastside and Coal Ridge No. 1 Mines to diminish or degrade the
hydrologic balance. The permit applications for these mines are located at
the offices of the Colorado Mined Land Reclamation Division, and are
designated as follows:
1. Eastside Coal Co., Inc.--Eastside Mine, CMLRD File No. C-84-063
2. Storm King Mines--Coal Ridge No. 1 Underground Mine, CMLRD File
No. C-84-065
These two mining operations are underground operations. The life-of-mine
areas of these mines are plotted on Figure 3. In addition, the area of
surface disturbance, the area to be undermined during the permit term, and the
area to be undermined during the life-of-mine are tabulated in Table 2.
The Coal Ridge No. 1 Mine and the Eastside Mine are both located along the
Grand Hogback Monocline. The Grand Hogback trends east-southeast in the area
with rock strata dipping to the south-southwest at an average of 500. The
general direction of ground water movement is down dip. The life-of-mine
boundaries of the Eastside and Coal Ridge No 1 Mines are 7 miles apart along
strike. The coal seams to be mined are located within the lower section of
the Mesa Verde Group in the upper portion of the Iles Formation (E-seam) and
the lower portion of the Williams Fork Formation (Wheeler seam). The
stratigraphy of the area is shown in Figure 2. These two seams are separated
by 200 feet of interbedded shales, sandstones, siltstones, and coal. The
five-year operation plan of the Eastside Mine calls for mining of the E-seam.
The Coal Ridge No. 1 life-of-mine plan calls for mining of the Wheeler seam.
The potential of the Mesa Verde to produce ground water within the area of
these mines is greatly limited by the extreme dip of the rock strata. An oil
and gas well drilled five miles southwest of the Eastside Mine encountered the
Wheeler coal at a depth of 1300 feet. Another well drilled approximately 6
miles southwest of the Coal Ridge No. 1 Mine encountered the Wheeler seam at
approximately 9000 feet in depth (Tremain, 1983).