GENERAL31521

• Permit No: C1982056
• IBM Index Class Name: General Documents
• Doc Date: 4/18/1983
• Doc Name: PROPOSED DECISION AND FINDINGS OF COMPLIANCE
• Permit Index Doc Type: FINDINGS
• Media Type: D
• Archive: No

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The area modelled (Figures 1 and 2) includes the Foidel Creek, Middle
Creek, Fish Creek, Grassy Creek, and Trout Creek drainages, and a reach
of the Yampa River from its confluence with Trout Creek to the USGS
gaging station at Hayden.
The Yampa River is the major perennial stream in the area. Its
headwaters lie in the mountainous areas to the north, east and south of
the study area. Flow in the Yampa River is dominated by snowmelt runoff
with more than half the annual flow occurring in April, May and June.
The U.S. Geological Survey maintains a gaging station on the Yampa River
near Hayden, Colorado. Data on the quantity and quality of streamflow at
this station are published annually in the U.S. Geological Survey's Water
Resources Data for Colorado.
Data on the smaller drainage basins are available from U.S. Geological
Survey gaging stations and from the mine permit applications on file with
the Division. Grassy Creek, Fish Creek, Middle Creek, and Trout Creek
are smaller perennial streams drainage the study area. Foidel Creek is
an intermittent stream. Data on the quantity and quality of flows in
these streams are available in the Seneca II Mine, Foidel Creek Mine,
Edna Mine, and the Energy Mine No. 3 permit applications. Specific data
on lower Trout Creek are not available, and had to be estimated from
other available data for Fish Creek and upper Trout Creek. Information
on the Foidel Creek, Fish Creek, Middle Creek and Trout Creek is
summarized above in this findings document.
This area includes several existing and proposed mines. Existing mines
include Apex No. 2, Edna, The applicant Mines No. 1, 2, and 3, Eckman
Park, Middle Creek, Seneca II, Grassy Creek, and Meadows. It is
anticipated that these mines will continue operations according to the
life-of-mine areas identified in their permit application. The Middle
Creek mine is anticipated to reopen and mine the identified life-of-mine
area. Two proposed mines, Trout Creek and Foidel Creek, are located in
the study area. The short-term scenario for the Foidel Creek Mine
includes discharge of water from the mine workings and depletion of flows
in Fish Creek, but, in consideration of Stipulation No. 2, does not
include discharge from the spoils well to the surface flow system. (See
discussion of Probable Hydrologic Consequences, Surface Water.)
In running the model, it was assumed that all short-term effects occurred
at the same time, that all long-term effects occurred at the same time,
and that, except for the discharge from underground mine, no "new" water
is added to the surface water system.
The U.S. Geological Survey water quality model was used to project the
cumulative effect of all anticipated mining in the general area of the
Foidel Creek Mine. The results are examined at four geographic
locations; lower Middle Creek {which includes the Foidel Creek drainage),
lower Fish Creek, lower Trout Creek, and the Yampa River near Hayden.