| The results of selenium exposure and bioaccumulation were illustrated at Kesterson Reservoir in 1983 to 1986. Monitoring, of the selenium concentration in ephemeral pools, is necessary to determine the exposure levels to which aquatic species and wildlife are exposed.; Historical records and newly acquired field data were used to assess the seasonal variation in ephemeral pool selenium concentrations. Water samples from ephemeral pools were taken from December to March, 1997, analyzed for total selenium. High concentrations (p = 3.9 {dollar}times{dollar} 10{dollar}sp{lcub}-7{rcub}{dollar}) were found in December/January, concentrations decreasing significantly thereafter. In December/January, 93% of the pools had a selenium concentration above 2-5 ug/l; March/April 75% of the pools still exceeded this goal.; This study also attempted to determine if selenium concentrations in the pools were changing with each successive season. Data was not consistent enough to be analyzed for this purpose. Recommendations are made on how to gather data to perform a multi-year analysis. |
