Iowa River IA 02-IOW-634

Assessment Comments

Assessment is based on results of monitoring of water quality monitoring from 1996-98 near Marengo for the USGS NAWQA program.

Basis for Assessment

Used results of fish tissue monitoring conducted for the USGS National Water Quality Assessment (NAWQA) program in September 1995.   The whole-fish composite sample of carp collected near Margeno was analyzed for several organochlorine compounds, including chlordane,dieldrin, DDT, and PCBs.   Levels of these DDT and PCBs in the whole-fish sample were less than one-half the respective FDA action levels.   Levels of chlordane and dieldrin, however, approached or slightly exceeded the 1/2 of the FDA action level of 0.3 mg/kg for both compounds.   Thus, assess fish consumption uses as fully supported/threatened (FST).   For more information on the USGS fish tissue study, see USGS Fact Sheet FS-027-97 (March 1997).  No information was available for developing assessments of support of the Class B(WW) aquatic life or Class A primary contact recreation uses for this river reach.