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concentrations. Since there are some high selenium waters in the study area we feel that several additional studies should be performed to determine how extensive the problem is. These are listed below. 1) A line of wells should be installed running in a transect from north to south on the terrace just east of the wetland. These wells should be completed through the alluvium and to bedrock. Well should be pumped to collect water several times during 1994 to determine if plumes of selenium rich water can be identified. If they can be identified, their source may be determined. Then it may be possible to develop best management practices for irrigated agriculture that would reduce the irrigation runoff from selected areas. The goal would be to develop irrigation methods which would keep the crops well watered without significantly contributing to the ground water table in the area. The reduced ground water flow may lower summer water levels in the wetlands. However, because the problem areas are not the main springs feeding the wetlands, reduction in their flows may not significantly reduce water levels. 2) Additional ground water wells in the area north of the wetlands should be in stalled to collect waters to again clarify the movement of selenium rich waters in the study area. 3) In situ toxicity tests using Cerodaphnia should be conducted on wetland waters several times during the summer. This may help determine whether these waters are toxic to sensitive indicator organisms. 4) Invertebrates from benthic and water column samples already in storage at CSU's Larval Fish Laboratory should be analyzed for selenium content. This would help determine whether selenium is present in the food chain. 5) Soils should be collected to determine where selenium is concentrated that cannot be detected by water analyses. The high selenium concentrations in the northern portion of the study area indicate that this area should be avoided for fish recovery program activities at the present time. Even if the groundwater flow path in this northern area is reduced, selenium salts may still remain in the soil that could cause future problems. 28