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<br />surface and infiltration, reviewing the data presented over <br />the last three years, precipitation patterns from 1992 to 1994 <br />do not show any correlation to the mine inflow. <br />H. Last year's report included inflow data from the West main <br />section together with the North main section. Since retreat <br />mining has occurred in the West main section of the mine, <br />inflow recordings are no longer available for this section. <br />Therefore, all the reported inflow increase is from the North <br />main sections this year. Retreat mining is also occurring in <br />the North main section and is planned to continue into 1995 as <br />the Mine Plan indicates (see Map 17). As retreat mining <br />progresses, inflow locations may become inaccessible for <br />monitoring purposes. <br />C. The mine inflow total given in Table 1 does not add up to <br />14,195,100 gallons and should be 14,194,720 gallons instead, <br />a difference of 380 gallons. Please clarify and verify which <br />number is correct. <br />II. Grouadxater Monitoring <br />A. TD for monitoring wells <br />Monitoring for depth of water on wells OW-8 (mined through), <br />OW-10, OW-16, OW-23 and OW-65 occurred quarterly per permit <br />requirements. Except for OW-16, the three wells (OWs-10,23 <br />and 65) continue to drop steadily, echoing a trend since <br />mining/monitoring began in 1978. OW-16 shows a rebound from <br />last year's low at -120.3 feet to -85.3 feet, a difference of <br />35 feet. This well has shown a pattern of peaks and valleys <br />over the last 12 years, often responding directly to surface <br />precipitation patterns and this peak is well within normal <br />range for this well. In addition, this area is undermined by <br />the shallow and abandoned workings of the Jack O'Lantern Mine. <br />The mine's workings are often a source of inflow that through <br />a network of fractures, allow surface precipitation to <br />infiltrate the well area. OW-10 shows the largest decrease in <br />water levels, declining from -129.4 feet in 1993 to -148.9 <br />feet this year. <br />Data for well depth in Exhibit 25, page 4 of the permit <br />application does not agree with the data submitted in the AHR <br />on Table 8. Please clarify and if necessary, revise page 4 of <br />Exhibit 25 to reflect the updated information as presented in <br />this AHR. In the 1993 adequacy letter addressed to EFCI, the <br />Division requested that the TD levels in wells MW-8, MW-10 and <br />MW-65 be verified. Taken from that letter is the following: <br />MW-8 should be 960 feet, now recording 1038 feet; <br />MW-10 should be 402 feet, now recording 460 feet; <br />MW-65 should be 1448 feet, now recording 1440 feet. <br />Please respond and clarify the depth of these xells as part of the <br />response to this adequacy letter. <br />