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i C A M B R I A Ms.Victoria McCartney , August,3:,2005 Cambria includes historical tables detailing well and boring construction data (Tabl), soil analytical data (Table 2), and grab groundwater analytical data (Table 3) in this work-plan. We also present a compilation of prior boring logs in Attachment5� PROPOSED SCOPE OF WORK To address the requirements of SJCEHD's May 18, 2005 letter, Cambria proposes seven CPT soil borings(CPT-12 through CPT-18)at the locations shown on Figure 2. Boring CPT-12 is proposed in the sidewalk near;the Best Western property east of the site, and CPT-13 is proposed on the Best Western property. Cambria will use groundwater data7from these k borings to assess the lateral extent of petroleum hydrocarbons and MTBE in groundwater east of u borings CPT-4,CPT-5, CPT-10, and CPT-11 at depths ranging from 50 to 90 fbg. Three borings (CPT-14, CPT-15, and CPT-16) are proposed near the existing UST complex. 6� Cambria will use soil data from borings CPT-14 and CPT-15-to assess soil conditions north and west of well MW-9. Cambria will use�groundwater data from all three borings:to asses"s the lateral extent of fuel oxygenates in shallow groundwater(between 20 and 40 fbg) in',the vicinity,of wells MW-8 and MW-9. Borings CPT-17 and CPT-18 are proposed north of the subject site. Cambria will use soil data a.U',La't40'+5�A-�from boring CPT-17 to assess the lateral extent of petroleum hydrocarbons in soil north of MW-7. Cambria will use groundwater data from borings CPT-17 and CPT-18 to assess the lateral extent of petroleum hydrocarbons and MTBE in groundwater north and northeast of borings CPT-4,CPT-5,CPT-9, and CPT-10 at depths ranging from 50 to 90 fbg. As discussed above, Cambria is proposing to collect soil samples to further assess the lateral extent of petroleum constituents in soil. The pre-remediation?oil.�samples were collected from 2'7 03 a 1989 to 1991, when depth to water was approximately 29 to 33 fbg. Current depth to water is approximately 17 to 19 fbg. The highest petroleum concentrations were detected in the pre- remediation samples at depths between 15 and 30 fbg in unsaturated soil. Cambria proposes collecting soil samples at these target depths (in the work plan below), but we note that these sample locations now lie beneath the groundwater table and that may complicate interpretation of the soil results. ` SJCEHD's May 18, 2005 letter stated that there is no soil data after remediation ended in 1996. Cambria notes that in March 2000, boring CPT-1 was advanced through the former UST pit, and soil samples were collected starting at 20.5 fbg. Soil samples were also collected from CPT-4 Qwe starting at 20.5 fbg during the same investigation. Cambria agrees that additional soil 3