Publication Summary

Inner Budd Inlet was placed on the 1998 303(d) list for polychlorinated biphenyls (PCBs) based on a 1995 sample of mussels with a PCB concentration of 21 µg/Kg wet weight (ww). The current project provided intensive sampling of mussels in 2002 to determine if the listing continues to be warranted. Samples of blue mussel (Mytilus trossulus) in the listed area had PCB concentrations of 7.0-9.6 µg/Kg ww, exceeding the 303(d) listing criterion of 5.3 µg/Kg ww. The PCB mixture most closely resembled PCB 1254. Continued listing of the water body segment is recommended. The downward trend in PCBs in the listed area indicates future monitoring rather than a TMDL study.

Inner Budd Inlet was placed on the 1998 303(d) list for polychlorinated biphenyls (PCBs) based on a single composite sample of mussels collected from a culvert at the mouth of Moxlie Creek where it enters East Bay. That sample had a total PCB concentration of 21 µg/Kg wet weight (ww). This concentration exceeded the 303(d) listing criterion of 1.4 µg/Kg ww which was in effect at the time of sampling. In 1998, EPA revised their health criteria for PCBs. Based on EPA′s reassessment of the cancer potency of PCBs, the new 303(d) listing criterion was set at 5.3 µg/Kg ww.

For this current project, more intensive sampling of mussels was conducted on September 6, 2002, to determine if the Inner Budd Inlet PCB listing continues to be warranted. Samples of blue mussel (Mytilus trossulus) from the sites in East Bay were found to have PCB concentrations ranging from 7.0 to 9.6 µg/Kg ww. All of these concentrations exceed the current 303(d) listing criterion of 5.3 µg/Kg ww. The PCB mixture found was in a form most closely resembling PCB 1254. A fourth site at Priest Point Park had an estimated PCB 1254 concentration of 3.0 µg/Kg ww.

The new PCB data for mussels in East Bay are sufficient to support the continued listing of the Inner Budd Inlet waterbody segment. Only the reference site, north of the listed segment at Priest Point Park, had a PCB concentration lower than the criterion.

Link to EIM data for User Study ID SGOL004