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No. 5 Mine Inflow Report <br />1.1 Introduction <br />Permit No. CO-044-81 issued October 19, 1983 required Empire Energy to <br />conduct a mine inflow study if the discharge exceeded the predicted <br />discharge by 20%. This requirement is set forth in stipulation 3 of the <br />above permit. Since that time the stipulation has been modified to <br />require annual inflow studies regardless of the amount of discharge. The <br />following is submitted to satisfy this requirement. <br />1.2 Geologic Setting <br />The No. 5 Mine operates in the F seam within the ]ower coal group of the <br />Williams Fork formation. The nearest important aquifers are the overlying <br />Middle Sandstone and the underlying the Trout Creek Sand>tone. <br />The Middle Sandstone consists of a complex assemblage of sandstone and <br />sandy shales that exhibit a generally coarsening upward nature. The unit <br />is interpreted as a marginal marine sandstone "barrier and/or distributary <br />mouth sediments". It is underlain by a significant impermeable shale, <br />ranging from 15 to 30 feet thick, which is in turn underlain by <br />irregularly distributed continental deposits such as interdistributary <br />bayfills (ranging from shales to sandstones), fining-upward point bar type <br />sandstones and coals. The Middle Sandstone lies from 60 to 150 feet above <br />the F seam. <br />The Trout Creek Sandstone (Iles formation) underlies the F seam by about <br />350 feet. It averages about 75 feet thick and it too is interpreted as a <br />marginal marine sandstone. The intervening strata consist of coals, <br />shales and sandy shales, with only occasional sandstone. <br />1.3 Prior Study <br />During May of 1983 a study was conducted to provide measured inflow data. <br />Since that study, mining has continued in the western and eastern portions <br />of the mine, with the majority of mining now occurring in the eastern <br />portion of the mine. <br />The results of the study are provided in Table 1. The reader is referred <br />to Map IV-11 for the location of the measuring stations. <br />Table 1 - 1983 Mine Inflow Study Result;s <br />Inflow <br />Location Index No. (9Pm) <br />West of Faults 8 8 <br />Fault 6,4 363 <br />1 Left Panel 3 30 <br />3 South 2 13 <br />Central Works 15 6 <br />