PERMFILE40010

• Permit No: C1981038
• IBM Index Class Name: Permit File
• Doc Date: 12/11/2001
• Section_Exhibit Name: VOLUME 5A - INFLOW MITIGATION
• Media Type: D
• Archive: No

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TABLE 2
WATER INFLOW INTO THE ORCHARD VALLEY MINE
AFTER 1989
MINE SECTOR MINED AREA MINE INFLOW TOTAL MINE
(acres) IN THE SECTOR INFLOW
(gpm) (gpm)
Mine inflow at the end of 1989 (Table 1) 8.7
North East 361 2.2 10.9
North 328 2.0 12.9
North-West 100 0.6 13.5
West 891 5.4 18.9
West (inflow
near surface
streams) - 8.2 27.1
South-West 442 2.7 29.8
South-West
(inflow near E.
Roatcap Cr.) - 3.7 33.5
TOTALS 2,122 24.8 33.5
3.0 IMPACT OF MINE INFLOW ON WATER USERS
3.1 Impact of Quantity
Due to the absence of major aquifers which could be impacted
by mining and the lack of water supply wells in the area, no
significant impact of mine inflow on local aquifers is
anticipated.
The previous analysis of water inflow into the mine in the
area under Stevens Gulch and East Roatcap Creek indicated
increased seepage.
The maximum seepage from Stevens Gulch was Calculated as 5.7
gpm. Stevens Gulch is an ephemeral stream that experienced less
than one month without any flow (September 12 - October 1, 1984).
During the remainder of 1984, the minimum flow was at least 0.026
cfs, and the duration of this low flow was only several days.
The depletion of the stream by 5.7 gpm would not occur at the
same location. Part of this loss would be experienced above the
West Mains (5.2 gpm) and part in the area of the D seam subcrop
into Stevens Gulch (0.5 gpm). At a flow rate of 0.026 cfs in
Stevens Gulch, the depletion of the stream by 5.7 gpm would
amount to 48 percent of the flow. The Fire Mountain Canal will
be abandoning their water rights on Stevens Gulch and CWI will
present a mitigation plan for the amount of 5.7 gpm in a separate
document.
The maximum seepage from East Roatcap Creek was calculated
as 5.4 gpm. The minimum flow in this stream during 1984 was
8 m unu.r.F:n r.u"i cnvr,