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Since mid-1987 hydrologic monitoring has been conducted primarily by Twentymile personnel. From 1987 to <br />1999 water quality analyses were primarily performed by ACZ Laboratories (formerly Bookcliffs) of Steamboat <br />Springs, Colorado. Beginning in 2000 water quality analysis are primarily performed by C.T.&E. of Denver, <br />Colorado. Prior to June, 1986 some water quality analyses were performed by [he CYCC laboratory. In May of <br />1995, a private firm (Miller Water Monitoring Service) was contracted [o assist with hydrology monitoring at the <br />Foidel Creek Mine. Three surface water sites addressed in this report (USGS 09243700, USGS 09243800 and <br />USGS 09243900) are monitored for flow by the US Geologic Survey (USGS). Prior to the 1989 Water Year, [he <br />USGS also collected and analyzed water qualiq` samples from these sites. Since [he 1989 Water Year, Cyprus <br />collects water quality samples for subsequent laboratory analysis. Unless otherwise indicated, all references to <br />"2000" in this report to refer to the 2000 Water Year. <br />BEDROCK GROUNDWATER MONITORING <br />The Wadge Overburden formation (including the W'auge coat seamj overlies the Trout Creek Sandstone and <br />underlies the Twentymile Sandstone. All three geologic units are monitored within the Foidel Creek Mine permit <br />area. <br />Wad e Over rburden: During 2000, seven Wadge Overburden wells (009-79-4, FBR-I I-A, 006-82-74C, 91 M006, <br />008-77-58, 93M001 rand 93M003) required monitoring for water levels field parameters, and water quality <br />parameters on asemi-annual basis. All monitoring requirements were completed a[ these sites with field <br />measurements obtained and water quality samples collected during April and September. Please note, however, <br />that well 93M00 as abandoned in advance of mining on 8/4/00. Tables 1 through 7 provide summaries of the <br />2000 Water Year data collected at each site. Tables la through 7a provide period of record statistical summaries <br />of collected data at each site. Tables 1 b through 7b provide period of record water level summaries for each site. <br />Figures 3 through 16 provide graphical representations of water levels and selected water quality parameters <br />recorded at each site. <br />The po[entiometric surface in the Wadge Overburden is generally observed to slope from south to north in <br />monitored wells in the vicinity of the TCC facilities as shown by water levels in wells 009-79-0, 006-82-74C, and <br />91M006. During 2000, the water levels in wells 009-79-4 (Figure 3) returned values comparable to those of <br />recent years. Well 006-82-74C (Figure 7) shows a return [o levels typical prior to the 1998 Water Year. Well <br />91M006 (Figure 9) continued to show a steady decline in water level. Ttte potentiometric surface reflected by <br />wells 93M001, 93M003, and FBR-11-A is generally observed to slope from southwest to northeast. Wells FBR- <br />11-A (Figure 5), 93M001 (Figure 13), and 93M003 (Figure 15) all showed declines relative to last fall. These <br />declines are associated with mining of the Eastern Mining District (EMD). Well 008-77-58 (Figure 11) has been <br />unaffected by mining and exhibits seasonal water level fluctuations. During 1998, this well experienced an <br />unusually long seasonal decline, but in 1999 and 2000 the previously established recovering water level trend <br />resumed. <br />~~ No anomalous water quality impacts attributable to mining were evident in data collected from Wadge <br />Overburden wells during 2000. At well 009-79-4 (Table 1), new minimum values were recorded far lab <br />2 <br />