(S/S) treatment is used to treat hazardous wastes for disposal, and in the remediation/site
restoration of contaminated land. S/S is a popular technology in brownfield (industrial
property) redevelopment since treated wastes can often be left on-site to actually
improve the sites soil for subsequent construction.
In the United
States, the Environmental Protection Agency (EPA) considers S/S to be an established
treatment technology. EPA has identified S/S treatment as Best Demonstrated Available
Treatment Technology (BDAT) for over 50 commonly produced industrial wastes and
has selected S/S treatment for 25% of its Superfund (abandoned or uncontrolled)
site remediation projects where the sources of contamination have been addressed.
S/S treatment involves mixing portland cement as a binding reagent, into
the contaminated media or waste. Portland cement can be used alone or in combination
with other materials including cement kiln dust, lime, lime kiln dust and fly
ash to achieve the desired treatment results Successful treatment is accomplished
through physical changes to the waste form, and often, chemical changes to the
hazardous constituents themselves.
Cement-based S/S is a flexible treatment
technology capable of treating a wide variety of contaminants while the contaminated
media remains in place (in-situ) or on previously excavated material.