1986-06-13_GENERAL DOCUMENTS - C1981018

• Permit No: C1981018
• IBM Index Class Name: General Documents
• Doc Date: 6/13/1986
• Doc Name: Permit Application Approval Package Fed Leases C-023703, D-047201, C-8424, C-8425, C-0126669
• From: OSM
• Media Type: D
• Archive: No

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diversion point could be trucked to the site until the ponds were prepared or
replaced (p. II.C-106b).
The operation is in compliance with the requirements of this section.
IX. Probable Hydrologic Consequences and Cumulative Hydrologic Impacts
Assessment - Rules , 2, , and 2. .6 2 c
The projected hydrologic impacts of mining Federal Coal Leases C-23703,
D-047201 , C-0126669, C-8424, and C-8425 have been added to the discussion of
cumulative impacts for all mine related activities.
Impact of the Mining Operation on Surface Water
Impacts to the hydrologic balance will occur as a result of the proposed
mine. Short term impacts which will occur as a result of surface facilities
appurtenant to the underground mine include reduction of water yield from the
mine plan area to the White River, increased sediment loads from disturbed
areas, and water quality degradation from the refuse disposal area. Long term
impacts will center on the effects of subsidence under Scullion Gulch and
Red Wash. See the subsidence section of this findings document for further
discussion of subsidence impacts.
Short term surface water loss will occur as a result of two factors:
retention of water in ponds and removal of water from the White River alluvium
(i.e. - Kenney Reservoir) by the well field. Runoff from disturbed areas will
be routed through sedimentation ponds, thereby reducing the amount of flow to
the White River. Evaporation losses will occur because the ponds will not
discharge run-off until some of the available storage volume is filled. Very
little of the impounded water will re-enter the ground water system due to the
clay liner installed in the pond during construction. Losses form the
D-Portal pond will be insignificant when compared to total run-off from the
Scullion Gulch watershed. The pond is designed to store run-off from 44 acres
while Scullion Gulch has a contributing drainage area of 7,552 acres at its
confluence with the White River. The refuse disposal area ponds receive
run-off from approximately 98 acres, which is a very small portion of the
2,950 acres—drained by the Red Wash tributary through the northern sector of
the permit area. Based on this information, the net loss of surface water
quantity to Red Wash and the White River will be negligible.
The water supply for the mine will come from the White River alluvial well
field at a withdrawal rate of 1 .34 cubic feet per second. This translates to
0.2 percent of the average annual flow in the river of 672 cfs. Even during
low flow conditions, when the average flow is 245 cfs, the withdrawal rate
will only be 0.55 percent of the available flow. Therefore, adverse impacts
on flow in the White River as a result of proposed withdrawal should be
minimal . Furthermore, the permittee has secured water rights downstream of
the mine that may be used if necessary to replace a depleted water source.
Construction of surface facilities in the permit area will cause temporary
increases in the amount of suspended solids in the surface water system.
Furthermore, concentration of chemicals associated with increased sediment
load, such as iron and manganese, will also increase. At the Deserado Mine,
mitigation of sediment loadiwill be accomplished primarily by sedimentation
ponds. Although sediment increases will occur in the early phases of
i