New York/ New Jersey Harbor: Alternative Methods for Ex ... - CLU-IN

Metal contaminants present in the dredged sediment, however, are not removed by the
melting process. Instead, the metals remain in the cement mixture. When the cement
product is made into concrete, the metals are locked into place. The concrete made with
GTI‘s cement product must pass specific leachability tests, such as the toxicity
characteristic leaching procedure (TCLP), before it can be marketed.
In the product-conditioning portion of the Cement-Lock Technology, the matrix melt is
either diffused into micrometer-sized fibers or pulverized into granules by freezing it with
a stream of quench water or high-velocity air. Special additives can be combined with
granulated fibers or pulverized matrix melt to create construction-grade cement.
Residuals
The residuals resulting from the GTI process can be categorized into two types: metals
and organic compounds. Most of the metal components are locked into the end-product,
the Ecomelt, while the majority of the organic compounds leave are converted to
innocuous gases, water, or salts.
Nine out of the thirteen RCRA metals, barium, cadmium, chromium, copper, lead, nickel,
silver, selenium, and zinc are locked into the end-use product (32). Two of the remaining
RCRA metals, arsenic and mercury are adsorbed into activated carbon, solidified, and
immobilized.
The organic contaminants, which may or may not be present in the sediment, include
polyaromatic hydrocarbons (PAHs), organochlorine pesticides, PCBs, and 2,3,7,8-
chlorine substituted PCDD/PCDF isomers. These compounds are transformed into
hydrogen, chloride, SO2, nitrogen, and organic carbon by the GTI process. These waste
components are then altered so that they can be released into the environment. All of the
modified forms of the waste components are innocuous, with two exceptions. These two
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