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Page 5 Cabral-McAdams Property August 29, 2006 Job No. 1828-092.02 REMEDIATION PLAN General The results of our investigations indicate that the vertical and horizontal extent of significant petroleum hydrocarbon contamination in soils beneath the area of the former underground storage tank is limited. Excavation and proper disposal of the petroleum hydrocarbon-impacted soil is considered the most practical remedial approach. It is estimated that the remedial excavation activities will generate on the order of 100 to 200 cubic yards of contaminated soil for off-site disposal. Remedial soil excavation and disposal should be performed by a properly licensed hazardous materials contractor. Excavated soils should be properly handled, manifested and disposed in accordance with applicable regulations. The remediation contractor should prepare an Environmental Health and Safety Plan to protect workers from exposure to contaminated soils and physical hazards during remediation activities. As indicated above, the results of our environmental investigations indicate that elevated concentrations of organochlorinated pesticides, lead, and arsenic were identified within localized areas on the subject property. A garage structure was located directly south of the former underground storage tank area; the structure was removed in the recent past. Near-surface soils within and directly adjacent to the area of the former structure are contaminated with arsenic. The remediation contractor must avoid any disturbance of this area to prevent cross-contamination (see Plate 2). Notification/Utility Clearance/Permits Our firm and SJCEHD personnel should be notified at least one week prior to initiation of remedial activities at the site. The excavation area is located near underground utilities; the locations of underground utilities at the site should be determined and marked so that damage can be avoided during remedial excavation. The contactor should contact the applicable agencies to determine if permitting is required for the remedial soil excavation; including a grading permit and air quality permitting. Soil Excavation Soils within the underground tank area should be excavated to clean limits as determined by our representative. Soil excavation should be performed using appropriate equipment such as a backhoe or excavator. Our exploratory borings indicate that subsurface soils in the vicinity of the former underground tank consist of silty sands and fine sands; the potential for caving during remedial excavation should be considered. Because the excavation may need to extend to a depth of at least 25 feet below the ground surface, and depending on excavation equipment depth limitations, benching may be required. Apparently clean overburden soils should be stockpiled separately from the excavated contaminated soils. All excavated contaminated soils should be