vii, 39 pages : illustrations (some color), color maps ; 28 cm.
General Note:
"National Water-Quality Assessment Program"--Cover. Shipping list no.: 2004-0061-P.
Additional Physical Form:
Also available via Internet from the USGS Web site. Address as of 01/28/04: http://water.usgs.gov/pubs/wri/wri034219/pdf/wri03 4219.pdf; current access is available via PURL.