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a 4.0 Installation of Ozone Sparge Points Appropriate permit applications and fees will be obtained from the San Joaquin County Environmental Health Department (SJCIEHD) to conduct the services described in this workplan. SJCIEHD will be notified at least 24 hours in advance of the proposed sparge point installation and a grout inspection will be scheduled with SJCIEHD. JJW will obtain �I a utility clearance through USA. A site-specific Health and Safety Plan will be prepared for this investigation. The ozone injection sparge points are laid out to give overlapping coverage with an assumed radius of influence of fifteen feet per point (figure 7). The radius of influence is derived from recommendations of the manufacturer of the ozone injection system and is based in part on the observed lithology primarily consisting of clayey, silt to fine, occasional medium grained sands interbedded with permeable silty and sandy clay zones. Ozone sparge point diffusers will be set approximately 15 feet below the9 roundwater surface at 50 feet bas at each location. In at least four of the boring locations, in proximity to the former UST excavations, JJW will also have diffusers set at 35 feet to remediate the impacted soil above the groundwater table. In at least four of the locations diffusers will also be installed at80 a 3o_f.eet bgs to effect remediation on the limited, known deeper hydrocarbon contamination. Exact placement of the. sparge points may vary somewhat due to recommendations from the Ozone-!,System manufacturer but will correspond to the known areas of hydrocarbon contamination and the contaminate concentrations and depths in the groundwater. To install the sparge points, borings are drilled to the desired !depth needed for sparge point placement. The 2 inch diameter, 30 inch long sparge points are set with 314 inch PVC risers with viton O-rings which terminate at the surface in ;flush mounted well boxes (traffic vaults). For single sparge point installations, a fine sand filter pack is set around the sparge point and to one to two feet above the sparge point. Two feet of bentonite is installed above the filter pack with cement grout from the bentonite to the surface as per SJCIEHD requirements. For multiple sparge point borings, the first sparge point is set at the desired depth and a fine sand filter pack is set around the sparge point and to one to two feet above the sparge point. Bentonite is installed above the filter pack to the next sparge point depth. When the last (shallowest) sparge point is installed in .the boring, a fine sand filter pack is set around the sparge point and to one to two feet above the sparge point with two feet of bentonite installed above the filter pack.with cement grout from the bentonite to the surface (figure 8). In the surface mounted well boxes the risers are connectedi to tubing that traverses underground to surface at the Ozone Injection Panel (OIP). The OIP contains an ozone generator, pump and related valving and controllers to operate the system. The OIP is mounted in a secure area near an electrical outlet for powering the system. Upon approval of this workplan, we will submit a cost estimate to Mr. John Cervantes of JC Trucking to conduct the proposed remediation plan. The cost estimate will be submitted to the State UST Fund for pre-approval. JJW GEOSCIENCES Inc. i�