Near field receiving water monitoring of trace metals in clams (macoma balthica) and sediments near the Palo Alto Water Quality Control Plant in South San Francisco Bay, California: 1999-2001

David, Carlos Primo C.; Luoma, Samuel N.; Brown, Cynthia L.; Cain, Daniel J.; Hornberger, Michelle I.; Lavigne, Irene R.

Abstract:

This report presents trace element concentrations analyzed on samples of fine-grained sediments and clams (Macoma balthica) collected from a mudflat one kilometer south of the discharge of the Palo Alto Regional Water Quality Control Plant in South San Francisco Bay. This report serves as a continuation of the Near Field Receiving Water Monitoring Study which was started in 1994. The data for 1999-2001 are interpreted within that context. Generally, metal concentrations in both sediments and clam tissue samples have been within the range of values produced by seasonal variability. Copper and zinc, however, display a continued decrease, recording the lowest winter maxima concentrations in both sediment and tissue samples in 2001. Yearly average of bioavailable copper, zinc and silver concentrations in 1999-2001 are some of the lowest recorded since monitoring began in 1975. A slight increase in mercury in sediments and selenium in tissue in early 2001 are also observed. These enrichments are believed to be mainly caused by hydrogeologic processes affecting the area although only continued sampling will confirm whether anthropogenic sources influence the concentrations of these elements.

Genre:

USGS Numbered Series

ProdID:

51174

Citation Author:

David, Carlos Primo C.; Luoma, Samuel N.; Brown, Cynthia L.; Cain, Daniel J.; Hornberger, Michelle I.; Lavigne, Irene R.

Citation Contributing Office:

Citation Datum:

Citation Day:

Citation Edition:

Citation Editor:

Citation End Page:

Citation Issue:

Citation Keywords:

Citation Language:

ENGLISH

Citation Larger Work Title:

Citation LatN:

Citation LatS:

Citation LonE:

Citation LonW:

Citation Month:

Citation No Pagination:

Citation Number Of Pages:

Citation Online Only Flag:

Citation Phsyical Description:

44 p.

Citation Projection:

Citation Public Comments:

Citation Publisher:

Citation Series:

Open-File Report

Citation Series Code:

OFR

Citation Series Number:

2002-453

Citation Search Results Text:

Near field receiving water monitoring of trace metals in clams (macoma balthica) and sediments near the Palo Alto Water Quality Control Plant in South San Francisco Bay, California: 1999-2001; 2002; OFR; 2002-453; David, Carlos Primo C.; Luoma, Samuel N.; Brown, Cynthia L.; Cain, Daniel J.; Hornberger, Michelle I.; Lavigne, Irene R.