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Phase II Subsurface Investigation Workplan 1301 East Lockeford Street Lodi,California 95240 April 20, 2022 Page 12 Objective The objective of the project will be to evaluate the potential impact of VOCs to soil and/or soil gas as a consequence of a release or releases from the historical on-site operations. To investigate the identified REC, Partner will conduct a Phase II Subsurface Investigation.The investigation scope will include the advancement of four borings to facilitate the collection and analysis of soil and soil gas samples. The proposed investigation scope is designed to evaluate the objective. Scope Sampling procedures will generally conform to the requirements of the San Joaquin County Environmental Health Department (SJCEHD), the State Water Resources Control Board (SWRCB), the Department of Toxic Substances Control(DTSC),and the EPA.A state-certified laboratory will analyze the samples and the project will be performed under the responsible charge of a qualified Partner representative. Laboratory results will be compared with San Francisco Bay RWQCB ESLs. Partner will perform the following tasks for the Phase II Subsurface Investigation: • Prepare a site-specific health and safety plan; • Notify Underground Service Alert North (USAN) a minimum of three business days prior to drilling activities to clear public utilities; • Secure the necessary drilling permit from the SJCEHD. Permit acquisition will involve submitting a completed application and site plan to the SJCEHD for review and approval and remitting the necessary fees.The turnaround time of the SJCEHD to issue the permit is expected to be no more than two weeks; • Notify the applicable regulatory agencies a minimum of 48 hours prior to drilling/backfilling activities; • Clear boreholes of utility lines through a geophysical survey. Boring placement will be modified as necessary based on the geophysical survey results to avoid damaging underground features. Additionally, to the extent practical based on subsurface lithology, clear boring locations using hand tools; • Advance four borings throughout the subject property to a terminal depth of 15 feet bgs, collecting soil samples at 2, 5, 10, and 15 feet bgs; • Field-screen each soil sample using a photoionization detector (PID); • Prepare up to 16 soil samples for laboratory analysis; • Install a temporary soil gas probe in each boring at 5 feet bgs. The final screening depth at each borehole will be adjusted based on the encountered lithology. In general, probes will be screened within coarser-grained materials and clayey/saturated intervals will be avoided, if possible; • Purge each probe, then collect and prepare up to four soil gas samples for laboratory analysis using laboratory-provided, batch-certified SUMMA canisters and flow controllers with a 5- to 10-minute sample period; • Analyze each soil gas sample (up to four soil gas samples total) for VOCs via EPA Method TO-15; • Based on field-screening results, analyze one soil sample per boring (four soil samples total) for VOCs via EPA Method 8260; and • Compare data to applicable screening criteria, and prepare a report summarizing field activities, methods, and findings. PARTNER 0 00