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1 <br />' Homestake Mining Company -Bulldog Mine-Lower Tailing Pond 12 <br />' 4.0 Conclusions <br />' ht 1978, when seepage was first noted down-gradient from the Lower Tailing <br />Impoundment, HMC implemented a series of investigative and remedial measures. As <br /> the effectiveness of the remedial measures were evaluated, the corrective actions were <br />' modified. It appeazs from the water monitoring results, that as the tailing water pool <br />declined in the impoundment after production was stopped in 1985, the water levels in <br /> the monitoring wells declined proportionately. The slurry cut-offwall constructed in <br /> 1982 appeared to effectively trap water exiting the impoundment and allowed for the <br />' collection and return of the water to the tailings impoundment. The remedial work in <br /> 1983 effectively retazded the seepage loss and increased the stability of the embankment. <br /> After mine closure and discontinued use of the impoundment for tailing disposal in 198, <br />' water levels in both the impoundment and the monitoring wells dropped and the cyanide <br /> levels decreased dramatically. However, metal values (lead, zinc and copper) were <br /> erratic and spikes appeazed in the data throughout the 1985-1989 period. This could be <br />' attributed to the ubiquitous nature of ground water in the Creede azea and the difficulty of <br /> securing samples from low producing well. The spikes can also be attributed to the <br />' samples not being filtered and total rather than dissolved constituents being analyzed. <br /> The samples that were secured from the few wells that did contain water in 1989 - 1993 <br /> reflected a trend towazds more stable water quality, indicative of background conditions. <br />1 <br /> <br /> <br />1 <br />1 <br /> <br />1 <br />1 <br /> <br />1 <br />