REP51867 - Laserfiche WebLink

Home Browse Search

• increasing although there appears to have been a leveling off since approximately 1989. The upstream site also reflects a notable conductivity increase in 1986, but also appears to be slowly declining. The difference between the conductivities at the upstream and downstream stations is attributable primarily to spoil spring discharges related to surface mining. These discharges cause increased concentrations of dissolved solids, calcium, magnesium, and sulfate and a reduction in SAR in Foidel Creek. However, the increase in TDS levels during irrigation season is not sufficient to cause material damage. While the spoil springs are adding some manganese to Foidel Creek, the level at Station 8 is still below the total recoverable standard of 1000 ug/I for Foidel Creek. Historically, high total recoverable manganese also has been recorded in the upstream station (14), indicating that these values may in some instances be attributable to non-mining related causes. Middle Creek: Middle Creek downstream of Mine 1 is monitored for flow and water quality at one location under the CYCC monitoring program. USGS Site 09243700, also known as site 700, is located on Middle Creek approximately one mile upstream of the confluence of Foidel and Middle Creeks (see Figure 2). The USGS maintains a continuous recorder at site 700 and provides data summaries to CYCC. During 1999, the Middle Creek surface water monitoring site required monthly flow and field parameter measurements with quarterly water quality sample collection. The monitoring requirements are further described to require 12 flow and field parameter monitoring instances to occur between March and September along with 4 water quality sampling events. All monitoring requirements were fulfilled at this site during 1999. Table 23 provides a summary of the 1999 Water Year data collected at Middle Creek surface • flow site 700. Table 23a provides the period of record statistical summary of collected data at the site. Table 23b provides a historical summary of flow rate data for the site. Figures 48 through 50 provide graphical representations of water levels and field conductivity data recorded at the site. Again, the typical flow pattern was exhibited at this site with the spring runoff period accounting for the peak filow observed. Runoff magnitude was about average during 1999, though down when compared to recent previous years data. The inverse relationship between flow and field conductivity was generally evident at this location. All monitored water quality parameters for surface water site 700 were observed to fall within previously established ranges for the 1999 Water Year, except for the new minimum values recorded for lab conductivity and TDS. Fish Creek: Three surface flow monitoring sites on Fish Creek are utilized. Site 16 is located upstream of the Mine 2 area; site 302 is located downstream of the Fish Creel Borehole mine dewatering site; and site 1002 is located approximately 2 miles further downstream and is monitored in conjunction with alluvial well 006-AW-2. One additional site, 307, is monitored for water levels only in conjunction with alluvial well 006-AZ-3. Station 16 replaced Station 1001 that was located upstream of where Fish Creek enters Twentymile Park. During 1999, the Fish Creek surface water monitoring sites generally required monthly flow and field parameter measurements with quarterly water quality sample collection. The monitoring requirements for all sites except 302 are further described to require 12 flow and field parameter monitoring instances to occur between March and September along with 4 water quality sampling events. All monitoring requirements were fulfilled at these sites in 1999. Required monitoring at site 302 included monthly flow, field parameter, and water quality sampling during the irrigation season June through September. Site visitation requirements were met at site 302. ~J cycc99 02/14/00