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2. zgw W_Wnm CP EQUIPMENT DESCRIPTION The equipment consists of a skid mounted unit incorporating the heat pump, air transfer ducting, heating and cooling heat exchangers, air filter, condensate collector, blowers, and power control panel. Units are available from 6,400 to 24,000 BTU's per hour, with air flow capacities ranging from 100 to 320 CFM. Auxiliary re-heating capabilities currently offered as an option are 2 KW, 4 KW and 8 KW, respectively, achieving reinjection temperatures up to approximately 350 degrees Fahrenheit. Support equipment necessary to install and operate the CP System are the injection and extraction wells, interconnecting aboveground manifolds and hoses. Special surface sealing precautions are required when the purging operation takes place at depths shallower than four feet below ground. Mobilization activities require a source of electrical power and protection against freezing. There are no residues generated, other than the liquid contaminants, which are removed from the contaminated vadose zone. In many instances the recovered condensate can be recycled for beneficial reuse. There is no atmospheric emission from this process. GENERAL A prototype CP System has been operating for over one year at a site where i, contamination exists from the surface down to 95 feet below grade. Typical removal rates are occurring at approximately four hours per gallon of condensate collected. The benefits of commencing the purge operations at the lowest level, e.g., capillary fringe, can be observed in the down-gradient, groundwater monitoring wells. This technique, i.e., starting purge at the lowest level, effectively arrests the downward migration of contaminants from tt, upper levels to the groundwater. With remediation occurring from the bottom up, the CP project can proceed without further endangerment to groundwater quality. This protection is achieved at the beginning of the project, without waiting for project completion, typically measured in years. Installation of the purge wells (injection and extraction) are no different than the standard wells typical of traditional vapor extraction system design. The economy of th_e CP System is seen in the operating expenses; typically $0.50 per hour for electricity, with no other expendable-materials:- The-contaminants-are-collected-as_a______ pure condensate of solvent and moisture, requiring no further treatment. This compares favorably to the traditional air cleaning apparatus in which it is necessary to remove and/or destroy the contaminants from the soil gas before it may be discharged to the atmosphere. 3