Publication Summary

The Washington State Department of Ecology conducts a long-term Marine Sediment Monitoring Task in Puget Sound as part of the Puget Sound Ambient Monitoring Program in conjunction with the Puget Sound Water Quality Authority. This report presents sediment data from samples collected in the spring of 1992 at 48 locations (stations) throughout Puget Sound. Components of this project include annual monitoring of 178 physical and chemical sediment parameters, sediment toxicity testing (amphipod bioassay), and the enumeration and identification (generally to species level) of the benthic infaunal community.

The Washington State Department of Ecology conducts a long-term Marine Sediment Monitoring Task in Puget Sound as part of the Puget Sound Ambient Monitoring Program in conjunction with the Puget Sound Water Quality Authority. This report presents sediment data from samples collected in the spring of 1992 at 48 locations (stations) throughout Puget Sound. Components of this project include annual monitoring of 178 physical and chemical sediment parameters, sediment toxicity testing (amphipod bioassay), and the enumeration and identification (generally to species level) of the benthic infaunal community.

Approximately two thirds (100) of the 156 organic compounds analyzed for from the 1992 samples were undetected in every sample taken. Of the organic compounds that were detected, the majority of values are qualified as estimates and are close to the detection limits. The majority of stations within the Marine Sediment Monitoring Task are located away from major sources of anthropogenic contamination. Few organic chemical compounds were detected at these locations. Several stations were located in the vicinity of the major urban areas around Puget Sound, although no stations were located within previously identified contaminated areas (i.e., cleanup or Superfund sites). The more "urban" stations tend to have the following chemical profile: all polyaromatic hydrocarbon compounds making up total HPAH and total LPAH were detected; at least one pesticide or PCB compound was detected; and, in general, more organic compounds were detected at these stations. Amphipod bioassays (sediment toxicity testing) results fail to prove toxicity at any station when the effects of sediment grain size are considered using the DeWitt model. Benthic infaunal data indicated that the lowest mean abundance, richness, and diversity values for the major taxonomic groups and for the samples as a whole occurred in stations which displayed high percent fines and total organic carbon values.