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Phase II Environmentai site Assessment Workplan 324 East 11th Street,Tracy,CA June 20, 2013 Page 2 of 5 PROPOSED SCOPE OF WORK Pangea's proposed Phase II ESA scope of work is detailed below. This work scope is designed to address RECs identified in the Phase I ESA, and to provide lateral and vertical hydrocarbon delineation of any detected onsite impact, as requested by your prospective lender. The proposed work scope includes the following tasks,as merited: • Task 1 —Geophysical Surveying to Search for USTs; • Task 2—Soil and Groundwater Sampling(4 Borings) • Task 3 —Contingent Borings for Lateral and Vertical Delineation, if merited, • Task 4—Waste Management and Disposal,and • Task 5—Phase II ESA Reporting. Task 1 — Geophysical Surveying Prior to conducting site field sampling work, PANGEA will use a subsurface specialty contractor to use geophysical techniques to search for potential USTs at the subject site. Geophysical surveying is often performed to help confirm the presence or absence of underground storage tanks (USTs). To survey the areas where USTs were potentially located, a geophyiscal survey would be performed using ground penetrating radar (GPR), electromagnetic utility locating methods, and a metal detector. The survey would look for metal tanks and subsurface anomalies (such as a rectangular pattern) where USTs could have been located. The surveying will be performed primarily west and east of the former dispenser canopy present in the center of the site, according to the 1967 aerial photograph in the Phase I. Geophysical surveying can also be used to clear proposed boring locations for underground utilities. To physically investigate for the presence of USTs, soil borings can be completed by hand to search for existing USTs within areas of subsurface anomalies. For this site we may complete one boring west of the former canopy,where the USTs were likely present in the past. (Note that Pangea contacted a current Chevron project manager who could not find any records on their database about the site.) Task 2— Initial Soil and Groundwater Sampling (4 Borings) Four soil borings are planned to evaluate the potential presence of petroleum hydrocarbons in soil and groundwater at the site. As shown on Figure 1, one boring(B-1) is currently planned west of the former canopy near the likely former UST location. A second boring (B-2) is planned immediately north of the former canopy, likely near the former dispenser location. Each of these locations are hydraulically upgradient of the hydrocarbon plume detected at the Tracy High School property across E. 11th Street. Boring B-3, planned south of boring B-1, is also near the possible former UST location. .Boring B-4 is located near the former dispenser location and