Accession Number:

ADA058445

Title:

Aquatic Disposal Field Investigations, Duwamish Waterway Disposal Site, Puget Sound, Washington. Evaluative Summary.

Descriptive Note:

Final rept.,

Corporate Author:

ARMY ENGINEER WATERWAYS EXPERIMENT STATION VICKSBURG MISS

Personal Author(s):

Report Date:

1978-06-01

Pagination or Media Count:

79.0

Abstract:

A multidisciplinary approach was utilized to study the physical, chemical, and biological effects of disposal of contaminated dredged material from the Duwamish River on a deepwater disposal site located in Elliott Bay, Puget Sound, Wash. A pilot survey, conducted in November and December 1975, was followed by a full-scale field assessment program. Observation of individual disposal events indicated that the sediment left the split-hull barges as a well-defined slug and reached the bottom in approximately 25 sec. A mound of dredged material 2.2 m high was created near the center of the disposal site. There was no physical of chemical evidence which indicated that any of the material reached the two reference sites located east and west of the disposal site. Chemical analyses of the in situ river sediment revealed concentrations of total sulfides and PCBs and interstitial water ammonia significantly higher than those for sediments from the disposal or reference sites. Chemical analyses of animal tissues collected at the disposal and reference sites indicated that the disposal operation did not result in higher levels of mercury and chromium in test animals. Mussels held at the disposal site for 3 weeks did accumulate PCBs to some extent however, background levels of PCBs in Elliott Bay waters were found to be relatively high before the operation. No adverse effects on demersal fish or shellfish were demonstrated.

Subject Categories:

  • Civil Engineering

Distribution Statement:

APPROVED FOR PUBLIC RELEASE