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Ground Water Monitoring 1 Quarterly ground water sampling for water level and water quality were conducted at each of the designated alluvial and deep wells. Samplings were conducted during March, June, and September. No sampling was conducted during December as approved by Technical Revision 19. Methods During visits to each station, water level measurements were made using aSoil-Test Indicating Depth Meter with a conductance bridge. Levels were recorded from the top of the well casing and reported as such. Water quality samples were collected during the quarterly field trips. Samples were obtained from a hand bailer, grabbing at least three casings o[water prior to sample collection. Parameters o[ temperature, pH and conductivity were made in the field. All sampling equipment and handling procedures were consistent with those described in the surface water methods section of this report. Results Results of all well water measurements collected during 1985 through 1990 are presented in Appendix 2 with major parameters summarized in Table 1. Information concerning well depth and completion is also presented in Appendix 2. The alluvial aquifer of S[ollsteimer Creek sampled at stations A-1, W-1, W-5 and W-7 indicate a direct connection with Iluctuations of the creek. Water elevations were highest during the higher flow period in the spring and lowest during the low (low period in the fall. Minor fluctuations occurred as a result of precipitation events. Because of the below normal runoff condiiions of the creek during 1990, alluvial water levels were also lower than previous years. In fact, Well W-1 was found to be dry during the September 1990 sampling. Water quality sampling of the alluvial aquifer was conducted at stations A-1, W-1, W-5 and W-7. In general, chemical parameters were consistent with those sampled in Stollstcimer Creek (Table 1). The water is considered a mixed ion calcium/magnesium-sulfate/bicarbonate type with a more stable ionic condition than the surface waters of the creek. Wells W-1 and W-7 are above mining operations and are analyzed as control stations while wells A-1 and W-5 are located in Martinez Meadow in and below the anticipated area of mining influence. Major parameters of these four wells are comparable (Table 1) excep[ conductivity and TDS at A-1 are somewhat elevated. The metal concentrations of aluminum, iron and manganese were significantly higher at wells A-1 and W-5 than sampled at W-1 and W-7. Stream concentrations of those metals at stations S ~ and S-3 have not indicated these significant levels. These concentrations may be linked to natural concentrations of the meadow soils. Since the Summer o[ 1987, the W-7 well has been utilized as a full-time domestic water supply. This usage appears to have little effect on water level in the well, however, the usage has decreased concentrations of the metal and other parameters being sampled. Deep wells completed in the Fruitland Formation were sampled at stations W-6, W-9, W-10, W-17, and VV-18. Wells W-17 and W-18 were eliminated from sampling under the current program. The general water Icvcl fluctuation cycle of these wells is an increase in Icvel from January through June, a decrease from July through October and a slight increase in November and December (Appendix 2). Station W-6 exhibited the greatest fluctuations ranging nearly 20 feet (Table t) and was nearly dry when measured in September 1990. Water quality of the deep wells was similar to that of the surface and alluvial waters. The waters are a mixed ion calcium-sulfate bicarbonate type. Chemical parameters were relatively stable over the year with greater ionization as water levels were lower. Same o[ the parameters such as iron and ammonia exhibited high concentrations during certain sampling events. Reasons for these spikes are not known, however, they may be linked to well completion and the steel casing.