Publication Summary

Sediment sampling was conducted at 18 locations in Grays Harbor during March 1998 to evaluate contaminant levels in ditches and backwaters near a variety of potential upland sources. Multiple stations were sampled at three of the 18 locations -- Grays Harbor Paper Mill, Little Hoquiam Boatyard, and Westhaven Cove -- to determine if a sediment station cluster of potential concern was present. A single location was sampled at the remaining 15 locations.

Sediment sampling was conducted at 18 locations in Grays Harbor during March 1998 to evaluate contaminant levels in ditches and backwaters near a variety of potential upland sources. Multiple stations were sampled at three of the 18 locations -- Grays Harbor Paper Mill, Little Hoquiam Boatyard, and Westhaven Cove -- to determine if a sediment station cluster of potential concern (SCPC) was present. A single location was sampled at the remaining 15 locations.

Chemical concentrations were low in most of the areas sampled in Grays Harbor. The majority of problems found for metals and organics appears to be localized around specific sites. The lack of widespread chemical contamination is probably related to relatively few large chemical sources being located in the area, in combination with an active sediment transport regime and good flushing in most parts of the estuary.

Of the three areas that were subjected to a station cluster analysis, one was classified as SCPC by Sediment Management Standards (SMS). Sediments near the Grays Harbor Paper Mill are a potential concern based on concentrations of 4-methylphenol. One additional site (Westhaven Cove), while technically not meeting the definition of a SCPC, had high enough concentrations of bis(2-ethyl hexyl) phthalate at two discontinuous stations to warrant concern. Both of these areas should undergo further evaluation. The third cluster site (Little Hoquiam Boatyard) did not have any chemical violations of the SMS. Six other locations that were screened for chemical contamination at a single site had one or more chemicals that exceeded the SMS.

A variety of large to fine wood debris was noted in sediments throughout the area. Besides organic enrichment of the sediments, it is unclear from the data collected what adverse impacts the presence of large amounts of wood waste is having on the benthic community of Grays Harbor. Biological testing is suggested to determine whether a healthy benthic community is present in areas with large amounts of wood waste.

Recommendations for follow-up actions are provided.

Link to EIM data for User Study ID GHSI