Coastal Marine Environment Sustainability - Sustainable Practices in Geoenvironmental Engineering - page 270

A study of heavy metals in ish and shellish was conducted in Port Philip Bay, Australia
(Fabris et al., 1999), with the objective of determining the partitioning of heavy meals in
dissolved and particulate species in the bay waters. Concentrations in the near-shore and
estuarine areas were not higher than in the coastal marine waters despite a lushing time of
10 to 16 months in the bay. The mechanisms for partitioning were related to co-precipitation
of iron and manganese oxyhydroxides with dissolved heavy metals. A strong correla-
tion of iron with chromium, nickel, and zinc was seen in the particulates. Contrary to the
metals, arsenic concentrations (as As(III)) increased in depth in the sediments and thus did
not seem to be the result of anthropogenic activity. Near the surface layer of sediments,
arsenic is oxidized to As(V) and leaves the sediments while Fe(III) can co-precipitate some
of the arsenic and become trapped in the sediments.

8.2.5.2 Sediment Quality Criteria

Table 8.1 gives an indication of the different criteria or deinitions structured by some
countries for characterization of sediment quality. Although many countries and jurisdic-
tions have established guidelines for water quality, and especially for drinking water, very
few countries have set up sediment quality guidelines. The importance of available guide-
lines and criteria can be seen in the need to protect pollution of the sea from dumping
and indiscriminate discharge of hazardous wastes—all of which will eventually ind their
way onto the sea bottom and ultimately into the human food chain. The 1954 International
Convention on the Prevention of Pollution of the Sea by Oil, together with the 1958 Geneva
Convention on the High Seas were the earliest formal attempts to regulate and control dis-
charge of hazardous substances into the sea. These have been reinforced with more atten-
tion paid to discharge of various kinds of hazardous wastes, especially wastes originating
from land sources.

TABLE 8.1
Outlines of Sediment Quali ty Guidelines

Country or Organization Criterion or Standard for Guideline

USEPA Screening concentrations for inorganic and organic contamination

SQCoc: Draft sediment quality criteria; oc: organic carbon
SQALoc: Sediment quality advisory levels
ERL: Effects: range—low
ERM: Effects: range—median
AET-L: Apparent effects threshold—low
AET-H: Apparent effects threshold—high
TELs: Threshold effects levels
PELs: Probable effects levels

U.S. National Oceanic and
Atmospheric Administration
(US-NOAA)

ERL: Effects: range—low
ERM: Effects: range—median

Canada ISQs: Interim sediment quality guideline

PEL: Probable effects levels

Australia ISQG-low: Interim sediment quality guidelines—low

ISQG-high: Interim sediment quality guidelines—high

The Netherlands Target value

Intervention value