PM08 Sediment Quality Assessment
Exhibit Hall
8:00 AM - Monday
(PM112) The Sediment Quality Triad Index in Puget Sound.
Dutch, M1, Long, E1, Aasen, S1, Welch, K1, 1 Washington State Department of Ecology, Olympia, Washington, USA
ABSTRACT- From 1997-1999, sediments were collected from 300 locations throughout Puget Sound as part of a joint monitoring program conducted by the Washington State Department of Ecology and the National Oceanic and Atmospheric Administration. Analyses were performed to quantify concentrations of potentially toxic chemicals, responses in laboratory toxicity tests, and the structure of benthic infauna communities in sediments. A Sediment Quality Triad Index was generated from these three data sets, and was used to classify and quantify sediment quality in six monitoring regions and five strata, and for the entire Puget Sound study area. While the majority of the Puget Sound study area had sediments of high quality (68%), 31% displayed some degree of degradation, while 1% was of lowest quality. Typically, the most highly degraded sediments were found in urban harbor areas (especially near the urban centers of Everett, Seattle, Tacoma, and Bremerton), near river mouths, and along shallow, nearshore areas. While small in area, these locations historically have represented and provided critical habitat for many species of marine biota, and degradation of sediments in these areas may have a disproportionate impact on the health of Puget Sound species. Results were also compared with data from estuaries and marine bays around the U.S. Relative to these locations, Puget Sound sediments were ranked among the least contaminated and toxic.
Key words: sediment quality triad index, Puget Sound