Why are the Illinois EPA and U.S. EPA proposing low temperature thermal desorption?
Unlike the other three source areas, the subsurface contamination in Area 4 is fairly well defined. It is also of a size and location suitable for excavation of the soils. LTTD is a well-known technology for treatment of soils contaminated with VOCs. When a LTTD is accompanied by an afterburner and a scrubber it is a safe and effective method of destroying the contaminants present in Area 4. In addition, excavation and LTTD take a much shorter time than other treatment technologies, and the method is cost effective when compared to other options. What would the treatment unit look like and where would it be located? Most LTTD units like the one proposed for Area 4 are mounted on two trailers of a tractor-trailer truck. The system would have a stack approximately 24 feet tall. The system would be located in the Area 4 parking lot. The Area 4 fact sheet for the feasibility study and proposed plan contains a figure that shows the temporary location of the treatment system. How long would
