Cedar River IA 02-CED-462

Assessment Comments

Assessment is based on results of (1) IDNR ambient city monitoring at Gilbertville from 2000-02and (2) U.S. EPA/IDNR fish tissue (RAFT) monitoring in 1997.

Basis for Assessment

SUMMARY:  The Class B(WW) aquatic life uses were assessed as "fully supported" based on results of IDNR/UHL ambient water quality monitoring.   Fish consumption uses were assessed as "fully supported" based on results of fish contaminant monitoring in 1997.   The sources of data for this assessment are (1) the results of monthly monitoring from January 2000 through December 2002 at the IDNR ambient city monitoring station located at downstream from Waterloo at County Road D38 bridge at Gilbertville and (2) the results of U.S.  EPA/IDNR fish contaminant (RAFT) monitoring in 1997.  

EXPLANATION:  The Class B(WW) aquatic life uses were assessed as "fully supported" based on results of monitoring from the IDNR ambient station at Gilbertville from 2000 through 2002.   Monitoring at this station showed no violations of Class B(WW) water quality criteria for dissolved oxygen, pH, ammonia-nitrogen, toxic metals, and toxic organic compounds in the 28 samples analyzed during this assessment period.   Fish consumption uses were assessed as "fully supported" based on results of U.S.  EPA/IDNR fish tissue (RAFT) monitoring in 1997 that showed levels of all contaminants were less than ½ of the respective FDA action levels and IDNR levels of concern.   However, because these data are now considered too old (greater than five years) to accurately characterize current water quality conditions, the assessment category is changed from "monitored" (indicating an assessment with relatively high confidence) to "evaluated" (indicating an assessment with relatively lower confidence).