Assessment Comments
Fish fish contaminant monitoring sites for ALCOA at Davenport.
Basis for Assessment
Continue to assess support of the fish consumption uses as NS due to existence of a fish consumption advisory on carp and carpsuckers from the Iowa side of Pool 15. Monitoring in the fall of 1996 showed that upper 95% confidence limits for PCBs in channel catfish, carp, and river carpsucker at the four sites monitored were all less than the FDA action level of 2.0 ppm; only mean and upper 95% CLs for carp at two sites exceeded 1/2 of the FDA action level (i.e., mean=1.03 and 95% CL=1.73 ppm at site 3; mean=1.18 and 95% CL=1.7 ppm at site 4). Thus, according to DNR methods for conducting 305(b) assessments of fish consumption uses, assess level of support as FST due to mean levels > 1/2 the FDA action level. Over the period of monitoring (1988 to 1996), levels of PCBs in fish from Pool 15 near the ALCOA facility have tended to decline, especially in 1996. Monitoring will again be conducted in fall 1998 to confirm that levels of PCBs in Pool 15 fish are well below the FDA action level.
