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Page 6 Cabral—Mc Adams Property April 28,2006 Job No. 1828-092.01 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 a permit is required for the remedial soil excavation. 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. Excavated soils should be stockpiled on visqueen. Stockpiled soils should be wetted as necessary to control dust and covered with visqueen. The visqueen should be secured as necessary to prevent wind disturbance. It is anticipated that the remedial excavation will occur during the summer months when significant rainfall is not anticipated. If rainfall does occur during excavation, controls (such as perimeter berms) should be implemented to prevent storm water discharge from the remedial areas. Additionally it should be noted that significant disturbance of surface pavements and landscaping, and potential encroachment into underground and above ground utility easements, is likely to occur. It will be the responsibility of the excavation contractor to implement appropriate excavation safety and security precautions. Stockpile Sampling and Landfill Acceptance An appropriate number of samples should be collected from the stockpiled soils generated during remedial excavation. The samples of stockpiled soils should be collected in accord with standard environmental sampling protocol, and should be submitted to a State-certified laboratory for analysis for TPH as gasoline and BTEX. The landfill may require additional analyses for acceptance purposes. The contractor should arrange for acceptance of the excavated/stockpiled soils at an appropriate permitted landfill facility. Clearance Soil Sampling Following excavation, soil samples should be collected from the limits of the excavated area. We anticipate the collection of four sidewall samples and one excavation bottom sample at this time. The clearance soil samples should be collected in accord with standard environmental sampling protocol, and should be submitted to a State-certified laboratory for analysis for TPH as gasoline and BTEX. Based on the results of the soil analyses, additional excavation may be deemed necessary.