Sediment Quality Values Refinement. Volume 2. Evaluation of PSDDA (Puget Sound Dredged Disposal Analysis) Quality Values. (Appendices A and B)

摘要

The report contains a detailed evaluation of the predictive reliability of dredged material disposal guidelines developed by the Puget Sound Dredged Disposal Analysis program. These guidelines were developed for use in evaluating the acceptability of dredged material for disposal in unconfined, open-water sites in Puget Sound and incorporate the following two kinds of sediment quality values: screening levels (sediment contamination below screening levels is assumed suitable for disposal without confirming biological tests); and maximum levels (the maximum levels indicate a level of chemical contamination above which a preponderance of toxicity information indicates the likelihood of unacceptable adverse biological effects). Evaluations conducted for the report indicate that current PSDDA screening and maximum level values are generally reliable in predicting adverse biological effects. Of 201 benthic infauna field samples and 287 amphipod bioassays field samples evaluated, approximately 93 percent are in accordance with the predictions of PSDDA values (i.e., they do not exhibit adverse effects at chemical concentrations below the screening levels and do exhibit adverse effects at concentrations above the maximum levels.)