PERMFILE50679

• Permit No: C1980004A
• IBM Index Class Name: Permit File
• Doc Date: 5/13/2002
• Section_Exhibit Name: APPENDICES K - P
• Media Type: D
• Archive: Yes

Mr. John Walters - page 5
• with the progress of the mine downdip, toward the northeast,
However, even at its peak, the water inflow into the mine was
relatively low. The average inflow into the mine decreased from
about 5 gpm after the cessation of mining to about 1.6 gpm during
the last four months. The decrease of water inflow after the
interruption of mining is explained by the expansion of the zone
of influence and by the depletion of the storage in the coal
aquifer.
Continuous monitoring of the water inflow into the mine and
of water quality within the mine should confirm the future trend
in decreasing and/or the stabilization of the inflow rate as
steady state conditions (the balance between recharge and
discharge) are reached. As discussed previously, a part of the
water inflow into the mine evaporates and is not accounted for.
The actual water inflow into the mine amounting to
approximately 1.6 gpm can not have any considerable impact on the
local hydrologic balance. The part of the water inflow that
originated from McClane Creek and is flowing into the mine along
the east fault is insignificant in comparison with the flow in
this drainage during snowmelt or after major storms.
The remainder (majority) of the inflow is believed to
• originate from storage in the Cameo seam and discharge from this
coal seam is insignificant in comparison with the quantity of
water stored in the general area of the Cameo seam or with the
recharge capacity into this coal aquifer. The Cameo seam
subcrops into the alluvial aquifer along East Salt Creek
approximately two miles north of the McClane mine.
It is not probable that water inflow into the McClane mine
would impact the alluvial aquifer in the East Salt Creek Valley
due to the distance between the mine and the Cameo seam subcrop
into this aquifer and due to the difference in elevation between
the mine and the coal recharge area on East Salt Creek.
The quality of water discharged from the McClane mine is
generally the same or better than water quality in East Salt
Creek at the confluence with McClane Creek. Therefore, water
discharged from the mine does not have any detrimental impact on
the water quality on the surface streams within and downstream of
the permit area.
Conclusions and Recommendations
The previous discussion indicated that at this stage of
mining activities when the mine is not expanding and is only
maintained, the water inflow into the mine is insignificant and
• is decreasing. Therefore, the potential for impact on the local
hydrologic balance is also insignificant. The water discharged
from the mine is of good quality and is generally better than the
water quality as monitored in East Salt Creek, downstream of the
permit area.
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