Contaminated Marine Sediments Assessment and Remediation (1989) / Chapter Skim
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The Use of the Sediment Quality Triad in Classification of Sediment Contamination
The Use of the Sediment Quality Triad in Classification of Sediment Contamination
Pages 78-99
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From page 78... ...
It consists of measures of sediment contamination quantified by chemical analyses, sediment toxicity determined with laboratory bioassays and benthos community structure described through taxonomic analyses of macrofauna. The chemical analyses provide information on the mixtures and concentrations of contaminants in the sediments that may be harmful to marine biota.
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From page 79... ...
In this type of evaluation the means and ranges in contaminant concentrations associated with the highest responses in the biological analyses can be compared with those associated with the intermediate and lowest ranges in those tests, using data from a variety of sampling sites. This type of evaluation can form the basis for predictive models in which the relationships between synoptically collected biological and chemical data are used to estimate the relative degree of contamination that is often associated with biological effects.
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From page 80... ...
Classification approaches that rely only upon benthos data may be frustrated by the major alterations in benthic communities that can be caused entirely or partly by differences among sites in depth, sediment texture, near-bottom or interstitial salinity, predation, bottom scouring, and other biotic and abiotic factors. While the three types of data from the triad concept provide complementary measures of sediment quality, the data from the three components may not necessarily parallel each other.
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From page 81... ...
summarized sediment bioassay and bottomfish histopathology data from Puget Sound and described the contaminant levels in sediments associated with high and low incidences of these measures of effects. Other uses of the triad concept are underway in studies being conducted by the Southern California Coastal Water Research Project in Southern California harbors (Karen Taberski, California State Water Quality Control Board, personal communication)
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From page 82... ...
~ Both the states of Washington and California are currently considering the possible development of effects-based sediment quality criteria, using AET values based upon triad data. The Washington Department of Ecology must adopt statewide sediment quality standards by June 30, 1989 in response to Element P-2 of the Puget Sound Water Quality Plan.
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From page 83... ...
In addition, sediment texture, total organic carbon content, total volatile solids content, sulfide content, and percent solids were determined for each station. Toxicity was determined with four bioassays: 1.
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From page 84... ...
Table 1 summarizes selected chemical data as RTR values. The data have been normalized to total organic carbon content and each concentration divided by the mean values for the SP reference site.
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From page 88... ...
OA05 ISLAIS WATERWAY (IS) SI ATIONS FIGURE 1 The Sediment Quality Triad determined for each station at each of the three study sites in San Francisco Bay.
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From page 89... ...
Chemistry RTR values are from Table 1; bioassay RTR values are from Table 2; infauna RTR values are from Table 3. Prom the triad of measures taken at the three sites in San Francisco Bay, it is apparent that the IS site was more contaminated, more toxic, and had a benthic community that was very different from those at the other two sites.
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From page 90... ...
In all cases, however, there were large ranges in contaminant concentrations within each level of bioassay response. The sample size available from this study is obviously very small, but with the addition of more data the patterns in co-occurrence of contaminant levels with biological effects measures could be established for San Francisco Bay and could, ultimately, lead to the calculation of indices such as AET for use in the bay.
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From page 91... ...
All the data are presented as RTRs using the mean values from the Carr Inlet reference area as the denominator. The mean RTR values for each of the triad components is shown to the right of each of the tables.
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From page 92... ...
chemical data indicated a distinct difference in chemical concentrations between the Hylebos Turning Basin and the adjacent Upper Hylebos Waterway, whereas the bioassay data indicated only a small difference between the two areas. The chemical data indicated that station 11 in City Waterway was moderately contaminated (mean RTR of 98)
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From page 93... ...
The mean RTR values were influenced mainly by the values from the amphipod abundance RTR values. Either none, one, or two amphipods were found in most of the samples.
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From page 94... ...
Table 7, Hylebos-23, City-13, and City-16 had the most highly altered communities. Total abundance and species richness were low at Hylebos23 and there were no amphipods there.
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From page 95... ...
\. Aft\ i"\ 1 \ \\ HY-22 .\ 100 '\\ I/ | | /b~CI-11 1 1 ll Chemical Conta~nabon 2QO; 40 Bents Alerabon 3~FIGURE 3 The Sediment Quality Triad for three stations in Commencement Bay waterways, based upon RTR values from Tables 5, 6, and 7.
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From page 96... ...
The toxicity data chosen for this example are those from the amphipod bioassay. The data from the chemical analyses are those for three organic compound classes, four trace metals, and total organic carbon.
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From page 98... ...
Data resulting from the three measures can be used to descriptively compare sediment quality among sampling stations, to classify or rank the relative quality of sediment sampling stations, to determine the spatial extent of poor sediment quality, to characterize putative uncontaminated reference conditions, and to estimate the contaminant levels associated with ranges in biological effects. This concept has been used in a number of assessments and surveys performed in various regions of the United States.
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From page 99... ...
1985. A Sediment Quality Triad: Measures of sediment contamination, toxicity and infaunal community composition in Puget Sound.
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