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(MW-17, if necessary)will be stepped out northward and just east of the intersection of South Harlan Road and J Street, o If lab analysis of the grab groundwater sample collected early on from MW-13 indicates MTBE impact,then a groundwater monitoring well (MW-18, if necessary)will be stepped out westward across Interstate 5 and in South Manthey Road. 4.0 SITE ACCESS Prior to commencing fieldwork, Environmental Remediation Group (ERG) will communicate with property owners to discuss the proposed scope of work, obtain permission and access agreements, and to address any concerns that the individuals may have regarding this additional assessment. 5.0 MONITORING WELL INSTALLATION ERG proposes to install up to seven groundwater monitoring wells (MW-12 through 18). The two-inch diameter wells will be double-completed with one casing screened across Sand A/Sand B and the other deeper casing screened across Sand C. We propose to screen the shallow interval across Sand A/Sand B since 1) it has been shown that these zone are hydraulically connected and 2)both zones show similar MtBE impact. Proposed groundwater monitoring well MW-16 will be installed adjacent to existing MWO-1X, which is screened across Sand B. Newly installed MW-16 will be single- completed and screened only across Sand C so as not to duplicate the efforts of MWO- 1X. The boreholes will be installed to a total depth of approximately 55 feet bg and converted to double-completed wells with screen intervals that intercept groundwater across Sand A/Sand B and Sand C. The shallow screen section will be installed approximately between approximately 5 and 35 feet bgs. The deeper screen section will be installed approximately between 50 and 55 feet bgs. Wells will be constructed of 2-inch polyvinyl chloride (PVC)casing material with 0.02 slot size. Wells will be installed using a truck-mounted drilling rig with a continuous flight,hollow-stem auger. The augers will be steam cleaned prior to drilling each boring. The soil borings will be sampled every five feet for soil lithology and select soil samples may be sent to a laboratory for analysis. Two borings/monitoring wells(MW-12 and MW-16)will be continuously cored. The soil types encountered and other pertinent data will be recorded on a field log and soil will be described in accordance with the Unified Soil Classification System (USCS). ERG will conduct field screening of the soil cuttings using an Organic Vapor Analyzer(OVA)and the results will be incorporated into the boring logs. Each of the borings will be installed by a geologist and overseen by a California Registered Geologist or Professional Engineer. Actual depths of the screened intervals will be based on the depth to water encountered during well installation. Wellheads will be completed using flush-mounted Christy boxes matched to the existing surface. Figure Environmental Remediation Group Page 3 Site Assessment Work Plan Project No.0406 Joe's Travel Plaza