PERMFILE46234

• Permit No: C1994082
• IBM Index Class Name: Permit File
• Doc Date: 12/11/2001
• Section_Exhibit Name: TAB 07 HYDROLOGIC DESCRIPTION
• Media Type: D
• Archive: No

• were calculated from aquifer tests of nine alluvial wells located on the Sage Creek,
Annand Drew, end Grassy Creek drainages (Tables 7.9 and 7-10). A single test at Seneca
II-Y yielded a value of 1.4 ft2/day while transmissivity values derived from tests of 7
alluvial wells at Seneca's nearby Seneca II Mine ranged from 7.5 to 439 ft2/day (30.1
2
ft /day geometric mean). Based on these data, it appears that the transmissive rate
within the Yoast alluvial system is toward the mid to low end of that determined for
nearby areas. Hydraulic conductivities for the Yoest alluvial wells range from .03 to
5.95 ft/day (geometrie mean of 0.41 ft/day), while storativity values range from 0.001 to
0.17 (geometric mean of 0.01). These are reasonable values for alluvial materiel,
although the figures for Yells TSAL1 end 12 seem a bit high (Table 7-9).
Madge Overburden. Aquifer tests of three Madge overburden wells yield transmissivities of
0.016 to 0.051 ft2/day (0.029 geometric mean), end hydraulic conductivities of 0.001 to
0.004 ft/day (0.001 geometric mean). Caleuleted values of these two parameters for the
nearby Seneca II-Y Mine are 0.32 to 0.72 ft2/day end 0.003 to 0.5 ft/day, respectively.
Robson end Stewart (1990) give values of 4.3 to 43 ft2/day (16.9 ft2/day geometric mean)
for transmissivity, and 0.1 to 0.6 ft/day (0.31 ft/day geometric mean) for hydraulic
• conductivity for this unit, and Stewart (1983) states a range of 3.1 to 43 ft2/day for
transmissivity alone (Table 7-11). These data suggest that the Yoast Madge overburden
wells are at or below the extreme low end of the local scale for both of these aquifer
characteristics. Storativity values ere also toward the low end at 1 x 10E-05.
Madge Coel. Four aquifer tests were performed on the Yoast Yedge coal CYells YY23, 2B,
29, and 30). Computed values for transmissivity range from 0.024 to 0.26 ft2/day
(geometric mean of 0.06 ft2/day), while hydr eulic conductivity ranges from 0.001 to 0.004
ft/day (geometric mean of 0.002 ft/day). These values compere favorably with those
obtained at the Seneca II-Y Mine, but ere et the low end of the range of values determined
for the region by the USGS (see Table 7-11).
Madge Underburden. Calculated transmissivities and hydraulic conductivities for the Madge
underburden are 0.024 to 0.126 ft2/day and 1x10E-OL to 1x10E-03 ft/day, respectively, for
three aquifer tests performed et Yoest. These are very much lower than published aquifer
characteristics for this unit (refer to Table 7-11).
. Yolf Creek Coel. A single pumping test et Yell YYC31 yielded a transmissivity of 0.33
ft2/day, and a hydraulic conductivity of 0.013 ft/day. Similar tests conducted by Peebody
et its Seneca lI-4 Mine yielded values of 0.001 to 0.2 ft2/day end 1x10E-04 to 0.01
35