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• within the baseline range of 454 to 900 mg/l. This well exists in the Hubberson Gulch alluvium upstream of mine discharges. Irrigation of the pasture surrounding this cell began May 6, 1989. All samples from this well collected after that date have had a higher TDS value than samples collected prior to that date. Samples from Well 7A2, located in the Hubberson Gulch alluvium downstream of mine discharges, display a CaMg•HC03504 type water with an average TDS value of 1,259 mg/l in 1993. This is higher than the 1,041 mg/l baseline average, but falls within the baseline range of 760 to 1,346 mg/l. Samples from Yell 19A, located in the alluvium of a Hubberson Gulch tributary (006 Gulch) that contains mine discharges from the NPDES 006 pond, display a NgCaNa-S04 type eater with an average TDS value of 1,842 mg/l in 1993. This is lower than the 2,158 mg/L baseline average, but falls within [he baseline range of 1,508 to 2,394 mg/l. Samples from YeIL 9A1, located in the Watering Trough Gulch alluvium upstream of all proposed and existing mining disturbances, display a CaMg-HC03 type water with an average • TDS value of 471 mg/l in 1993. This is lower than the 489 mg/l baseline average, but falls within the baseline range of 404 to 566 mg/l. Monitoring of eight additional alluvial wells is required as part of the monitoring program established on October 4, 1991 (see preceding Alluvial Ground Water Level section). Sampling was started at these eight wells in the fall of 1990 (GY-52Y series eel ls, see Table 5, Appendix A), or in the spring of 1991 (USGS series wells). All data collected prior to September 30, 1992 has been averaged together to provide baseline information for the milliequivalent table (Table 5, Appendix A). In addition, all 1993 data is also provided. Yell 20R (NPDES 005, Dry Creek Basin) had no water to sample since monitoring began. All USGS series wells are situated on Sage Creek upstream of mining, chile all the new GW-S2W series wells (except Yell 20A, see above) are also on Sage Creek and, as of yet, have not received mine discharge eater from NPDES 009. A descriptive evaluation of the eater chemistry of these seven cells will be provided when NPDES 009 begins discharging. Madge Overburden. Samples from Well 140V, located in the north mining area uh ere mining began in November, 1992, display a MgCe-504 type eater with an average TDS value of 3,111 mg/t for 1993. This value is both loner than the baseline average (3,513 m9/l) and the baseline range of 3,464 to 3,562 mg/l. Lower TDS values are likely a result of increased 5