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Ground Water Monitoring With CMLRD approval of Technical Revision 19, no groundwater sampling was required during 1991. However, during reclamation activities conducted during 1991, CMLRD ' approved reclamation of the monitoring wells. Prior to reclamation of the wells in August 1991, one last sampling was conducted. Results are discussed below. ' 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 of water prior to sample ' collection. Parameters of 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 1 Results of al] well water measurements collected during 1985 through 1991 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 Stollsteimer Creek sampled at stations A-1, W-1, W-5 and W-7 t indicate a direct connection with fluctuations of the creek. Water elevations were hig}test during the higher flow period in the spring and lowest during the low flow period in the fall. ' Minor fluctuations occurred as a result of precipitation events. Well W-1 and W-5 were found to be dry during the August 1991 sampling. Water quality sampling of the alluvia] aquifer was not conducted during 1991. However, chemical parameters of previous ' samplings were found to be consistent with those sampled in Stollsteimer 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 Matrinez Meadow in and below the anticipated area of mining influence. Major parameters of these four wells are comparable (Table 1) except 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-2 and S-3 have not indicated these significant ' levels. These concentrations may be linked to natural concentrations of the meadow soils. Since the Summer of 1987, the W-7 well has been utilized as a fu]]-time domestic water