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2829 W. Washington Street, Stockton, CA 95206 Permit Item 9a. Describe,in detail,how the soil and/or water sample(s)beneath the tank and piping will be collected. The contents(water)of concrete vault will be removed and immediately following evacuation of the vault,it will be removed/excavated out of the ground. The top 1 to 2 feet of the vault are exposed at the surface,as well as the entire southern and eastern sides of the vault. Therefore,using either an excavator or backhoe,the concrete structure will be pulled up and out of the ground. Soil samples are required to be collected in the vault pit from both sidewalls and from beneath the vault. Therefore,if the vault pit can be safely entered (in accordance with Cal OSHA standards), ERM personnel will collect soil samples from the required locations by hand. If unable to be entered safely,the soil samples will be collected from the vault pit sidewalls and base with the assistance of the excavator or backhoe bucket. Soil samples will be collected in the appropriate pre-cleaned, laboratory-supplied containers,in accordance with proper USEPA method guidelines. A single groundwater sample is required to be collected from the base of vault pit. If the vault pit can be safely entered (in accordance with Cal OSHA standards), ERM personnel will collect the groundwater sample by hand. If unable to be entered safely,the groundwater sample will be collected from the vault pit using a mechanical device such as an extra-long bailer. The groundwater sample will be collected in the appropriate pre-cleaned, laboratory-supplied containers,in accordance with proper USEPA method guidelines. Permit Item 11a. Handling of excavated soil: What material will be used to line the tank pit and cover the stockpile? As described above,the vault will be removed using a backhoe or excavator. During removal,it may be necessary to over-excavate around the edges of the vault and remove residual soil along with the vault. Any soil removed during this process will be stockpiled on visqueen (plastic sheeting) pending laboratory results. If determined to be contaminated,the soil will be hauled off-site under RWQCB oversight. If not contaminated,it will be reused as clean backfill in the vault pit. Additional clean soil (from an off- site source)will be used as backfill as well. RWQCB oversees this action. The stockpiled excavation spoils will be covered with plastic sheeting when not being handled.