November 2008. This information is current and in use.
Frequently Asked Questions concerning the Florida Coastal Sediment Quality Guidelines
Are the Florida Coastal Sediment Quality Guidelines (SQAGs), published in 1994, enforceable by the Florida Department of Environmental Protection in the same manner that the department enforces surface or groundwater quality standards?
No, the SQAGs are sediment concentration guidance values to be
used by project managers in assessing conditions at such areas as
hazardous waste cleanup sites or wetland restoration sites. There
are no state, or federal for that matter, criteria or standards
for contaminated sediments, with the exception of Washington
state's Department of Ecology standards. The Department could
consider sediment removal as an option is if there is a
corresponding surface or ground water quality violation at the
What are the most common uses of the SQAGs?
They provide guidance to FDEP regulators, private consultants, and
other local officials that are concerned that a sediment or
wetland may have high levels of contaminants. These SQAGs are
intended to help identify priority areas for nonpoint source
control (e.g., sediment hotspots due to stormwater impacts to an
estuary), design wetland restoration sites, screen contaminated
sediments at waste cleanup sites, and monitor trends in
environmental contamination at a site over time (e.g., at a sewage
treatment plant outfall).
Can the SQAGs be used to evaluate dredge spoil disposal options?
Yes, the SQAGs are useful in determining the extent of sediment
contamination in sediments to be removed, however, they are not
intended to be used in place of federal dredged material
evaluation protocols (e.g., U.S. Environmental Protection Agency,
U.S. Army Corps of Engineers).
Is there a method to distinguish between the natural background
value of metals in sediment versus the anthropogenic pollution
that has occurred at the same site?
Yes. The Department has researched this important issue and
prepared a guidance document that can answer this question,
Guide to the Interpretation of Metals Concentrations in Estuarine
Sediments, published in 1988. More recently, an evaluation by DEP
staff shows that similar assessment approaches can be used for
evaluating metals in Florida freshwater sediments.
Both the SQAGs and the Guide to the Interpretation of Metals
Concentrations in Estuarine Sediments refer to coastal or
estuarine sediments Can we apply these documents to freshwater
Yes, the values provided in the guidelines compare favorably to
similar guidance numbers derived from freshwater studies. Florida
coastal sediments have similar geochemical compositions as
freshwater sediments, because both coastal and inland Florida
surficial geology is dominated by marine limestones/dolostones,
marine clays, and quartz-rich sand deposits. One important
difference is that the amount of organic carbon is often greater
in freshwater sites than in most coastal sites, especially in
certain lake systems.
The SQAGs were published in 1994, and the Guide to the
Interpretation of Metals Concentrations in Estuarine Sediments was
published in 1988. Can we still use these documents today and into
the next century?
Yes, the principles outlined in both documents are based on
relationships that should not change significantly.
Have the SQAGs of the Metals Interpretation document been through
a peer review process?
Yes, the SQAGs and the metals assessment approach have been
published in peer reviewed journal articles.