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Page 2 of 3 System Design The ozone injection well will target the zone of highest ground water concentrations in the source area. The proposed well will be located just up gradient of well MW-2 (Figure 2- Site Plan) and the sparge point (the micro-porous section) will be installed at the bottom of the aquifer thickness to be remediated. This design will provide proper lateral and vertical dispersion of the released ozone and ensure adequate coverage of the plume. Cone penetrometer data (Gregg 2002) indicate that the 30-ft to 65-ft depth of the saturated zone is comprised mainly of silt interspersed with fingers of sandy silt, clayey silt and cemented sand. The sparging literature and sparge point manufacturer guidelines suggest that the desirable range of permeability for air or ozone sparging is 10-1 to 10-5 centimeters per second. These fine-grained materials are likely near the lower end of the desirable permeability range but may still be feasible for sparging. The radius of influence (ROI) is related to injection depth, soil permeability, and interconnected pore channels present in the subsurface. The proposed injection well specifications are as follows- IW-I, 2-inch diameter, PVC Schedule 80, 0.020 slot size, screened 55-65 feet, with a total depth of 65 feet. A commercially available, packaged ozone generatorlinjection system will be used to provide the ozone. These systems typically operate on 110-volt power and can be obtained skid-mounted with a relatively small footprint. The KVA C- Sparger ozone generator and bubbler can deliver ozone through appropriately sized tubing terminating in an 18-inch long sparge point. The system will likely require an injection pressure of 15-25 pounds per square inch. The ROI is expected to be in the range of 25 to 50 feet. Although ozone system manufacturers claim that vapor emission control is not required we believe it would be prudent to operate in conjunction with a soil vapor extraction system. Detailed design,Permitting and Installation Detailed design will require complete system sizing and selection, packaged equipment schematics, an electrical one-line diagram, piping/trench/well construction/equipment-anchoring details, and a site plan with equipment layout. A fence may be required to secure the packaged equipment and control panel. The system will likely require a building permit and electrical and fire inspections after equipment installation and before startup. We believe the detailed design can be completed within four weeks of completing the recently approved site characterization. Ground Water and Remediation System Monitoring The bubbler apparatus will be operated for an initial period of six months to evaluate the performance of this approach for reduction of COC concentrations. The network of existing and new monitoring wells (Figure 2) will be used to gage the effectiveness of the injected ozone.