Fairfield Reservoir 2 IA 03-SKU-910

Assessment Comments

Basis for Assessment

Lake was monitored on March 30, 1993 for 7 ag herbicides in water and sediment at one location in the reservoir.  Atrazine (1.1 ug/l) and cyanazine (1.2 ug/l) were detected; none of the other 5 herbicides were detected; no herbicides were detected in sediment.   Compared to results from the other 14 reservoirs, levels of atrazine were relatively high.   In addition, results of monitoring at Corydon Reservoir (Kalkhoff 1993) suggest that levels of ag herbicides in summer may be greater than the MCL.   Additional monitoring during summer is needed at this reservoir.   Because levels of atrazine < 1/2 MCL, DW uses were assessed as FST.   Fishable uses were assessed as PS based on BPJ used in 1992 305(b) report with sediment from agriculture identified as the primary cause of impairment.