Sediment Quality in Puget Sound Year 2 - Center for Coastal ...

urchin fertilization test for stations 197 and 199-20 l(62-73% of controls), and in the cytocl~rome
P450 HRGS assays for all seven stations (96.6 - 153.5 pglg). The cluster of three stations at the
moutll of the western fork of the Duwamish River (stations 197-199) were similar in their
infaunal community composition, with high abundance and taxa richness values (806- 1391, and
71-90, respectively), and moderately lligll evenness and SDI values (0.633-0.679, and 9-12,
respectively. Infaunal assemblages at these stations shared only two species from the dominant
species, including E~/philonzedes curcharodo?zta and Pa~vil~~cina te?z~~isc~[lpta. The more diverse
and abundant infaunal assemblages at these three stations do not strongly support the triad of
sediment parameters suggesting pollution-induced degradation at these stations. Tlle benthic
communities at station 114 and at the three East Harbor Island stations (200-2031, however, all
provide better support for the triad weight-of-evidence suggestion of pollution-induced
degradation at these stations. Benthic assemblages at these four stations supported high
abundance and richness values (980-1572, and 42-57 taxa, respectively), but low evenness and
SDI values (0.386-0.598, and 2-5, respectively). Numbers of pollution-sensitive taxa, including
arthropods and ecl~inoderms were low (2 1-37 arthropod taxa) or absent (0 ecl~inoderms) in these
samples. hlfauna abundance was high in all four samples due primarily to very high numbers of
pollution-tolerant species incl~~di~lg Aplzelochaeta species Nl , Hetero~~zastz~s,filob~~a~zclz~~s,
Scoletonza l~[ti, and A,~i~zopsida serricata.
In the Duwamish, two of the three stations (204 and 205) llad significant levels of chemical
contamination and toxicity. These stations had high concentrations of up to 7 toxicants,
including PCBs, HPAHs, 4-metl~ylpl~enol, pentacl~lorophenol, and butylbenzylphthalate.
Cytochrome RGS values were significantly elevated (47 - 77) at these two stations. As wit11 the
4 stations around Harbor Island, these two stations llad abundant benthic infauna (1 155-1561)
and high taxa richness values (52-651, but lowered evenness (0.373-0.454) and SDI (2-3) values.
The infaunal communities at these stations were composed of high numbers of the pollutiontolerant
species Aphelochaeta species N 1, Scoletonzu lzh, and Nz/tricola lordi. Again, the triad
weight-of-evidence appears to support the identification of pollutio~~ induced degradation at these
two stations.
In total, it appeared that 18 of the 36 stations in which both chemistry and toxicity measures were
significantly elevated also possessed benthic infaunal assemblage structure that may have been
influenced by the chemical and toxicological parameters measured at each station. These 18
stations were located in Sinclair Inlet (61, Dyes Inlet (21, Elliott Bay (41, in the waterways west
(1) and east (3) of Harbor Island, and in the lower Duwamish River (2). These 18 stations
represented an area 8.1 km2, or about 1.1 % of the total survey area.
Summary
A review of the compiled set of triad data of toxicity, chemistry, and benthic infauna indicated
that of the 100 stations sampled, 36 had sediments with significant toxicity and elevated
chemical contamination. These stations were located in Port Townsend (I), the central basin (31,
the Bainbridge Basin (2), Dyes Inlet (21, Sinclair Inlet (61, and Elliott Bay and the Duwamish
River (22). Together, these stations represented an area of 99.73 km2 or about 14% of the total
survey area. Of these 36 stations, 18 appeared to have benthic communities that were possibly
affected by chemical contaminants in the sediments. They included stations 160-165 (Sinclair
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