PERMFILE134633

• Permit No: C1982056A
• IBM Index Class Name: Permit File
• Doc Date: 12/11/2001
• Section_Exhibit Name: 2.04 Information on Environmental Resources
• Media Type: D
• Archive: Yes

• All surface bodies of water, impoundments and irrigation diversions in the general area are shown on Map 15,
Alluvial Valley Floor and Water Rights.
Kuowu Uses of Surface Water
Area surface water utilization is limited to the perennial streams of Trout Creek and Fish Creek and consists primarily
of flood irrigated agricultural operations. A relatively minor amount of surface water is utilized for stock watering
which is the only other significant use of surface water in the Trout Creek drainage. Domestic utilization of surface
water in the general area is limited by intermittent stream flows, low flow volumes, and relatively poor water quality.
Registered surface water rights in the permit and adjacent areas are provided on Table 12, Summary of Surface Water
Rights, and are shown on Map 15, Alluvial Valley Floor and Water Rights.
Flow Characteristics of Surface Draioaaes
The flow characteristics of area streams generally reflect topographic and geologic conditions as well as
climatological factors. As previously noted, the Twentymile Park structural basin controls area surface water
movements. Structural trends are generally reflected in the surface topographic configuration with area streams
Flowing from southwest to northeast along the northeastward plunging axis of the basin. Aerially, the geologic
structure is also significant with respect to the pattern and characteristics of ground water discharges to the surface
water system. Localized variations in geologic structure and lithology are typically reflected in the configuration of
the stream channel and floodplain.
A number of climatological and environmental factors are significant with respect to the surface hydrologic regime.
Limited annual precipitation, combined with the occurrence of most of the precipitation as snowfall, are the principal
factors affecting area stream flows. Snow, which has accumulated over the winter, melts rapidly as temperatures
• increase in the springs. This rapid snowmelt and consequent runoff result in a short period of high stream flows
extending from mid-spring through the early summer months. With increased temperatures and decreased
precipitation during the summer and fall months, soil moisture levels, which approached saturation during spring melt,
are rapidly depleted. Under these conditions, most of the limited precipitation, which is received, infiltrates into the
upper soil horizons and is subsequently released through evaporation or transpiration. Runoff, except in response to
major stone events, is insignificant and streamflows decrease accordingly.
The U.S. Geologic Survey-Water Resources Division (USGS-WRD), CYCC and TCC have collected considerable
information on the flow characteristics and water quality of major and tributary drainages. Principal surface water
monitoring locations in the general area are shown on the Twentymile Park Hydrology Map (Map 13). Streamflow
data are included in Table 10, Surface Water Data.
Foidel and Middle Creeks flow only in response to springs snowmelt and major storm events. The variation in
streamflow characteristics above and below the mine plan area on Foidel Creek are shown on Figures 5-a through 5-c,
Streamflow Hydrographs. USGS Station 09243800 is located immediately upstream of the mine plan area.
Monitoring of flows at this station was discontinued in October, 1983. CYCC Site 14, located about 3500 feet
upstream of the USGS station, consists of a weir and staff gage for monitoring flow on Foidel Creek immediately
upstream of the south tributary. Flow measurements have been taken several times per month during the spring and
summer flow period since March of 1982. A comparison of hydrographs during the 1982 and 1983 water years snows
that considerably higher flows have occurred at the USGS Station 09243800 downstream of Site 14, apparently as a
result of contributions from the south tributary to Foidel Creek including runoff from portions of the Eckman Park
Mine (Figure 5-a).
The streamflow hydrographs in Figure 5-a and the average monthly summary for USGS Station 09243800 in Figure
. 5-b show that over 80% of the present runoff occurs during snowmel[ runoff in April and May.
During the seven year monitoring period at USGS Station 09243800, average annual discharge has varied from 0.02
cfs in water year 1977 to 2.0 cfs in water year 1980. The longest no flow periods in water years 1976, 1977, 1978,
pPPR®i/CD APR 2 4 2000
Permit Renewal No. 3 2.04-31 4/1/99