Winnebago River IA 02-WIN-826

Assessment Comments

Assessment is based on fish tissue monitoring in 1998 and two water quality studies conducted for Lehigh Cement Co. in 1994-95.

Basis for Assessment

SUMMARY:  The Class B(WW) aquatic life uses remain assessed as "fully supported / threatened."  The fish consumption uses were assessed as "fully supported."  EXPLANATION:  Continue to use the assessment of support of the Class B(WW) uses developed for the 1998 report  that was based on results of water quality studies conducted in 1994 and 1995 by the University of Iowa Hygienic Laboratory for the Lehigh Portland Cement Company.   Results from these studies are approximately 5 years old and thus can be used to assess current water quality conditions.   As stated in the assessment for the 1998 report, results of these studies suggest a potential water quality problem; follow-up  monitoring is needed to better determine the status of the aquatic  communities of this reach of the Winnebago River and to determine whether the Class B(WW) uses may be impaired.   Fish consumption were assessed as "fully supported" based on results of EPA/DNR fish tissue monitoring in 1998 on the Winnebago River east of Mason City.   This monitoring showed that levels of all contaminants in the composite samples of fillets from carp and walleyes were well below ½ of the respective FDA action levels and DNR levels of concern.