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On February 26, 2021, cone penetration and groundwater sampling activities were conducted to evaluate the horizontal extent of petroleum impacted groundwater in the intermediate zone off site to the east. Relatively low concentrations of petroleum hydrocarbons were detected in the groundwater sample collected from 90 feet bgs at CPT-1 located east of the subject site. Petroleum hydrocarbons were not detected in the groundwater sample collected from 88 feet bgs at CPT-2 located northeast of the subject site. Refer to ATC's Off-site Groundwater Investigation Report, dated April 30, 2021, for additional information. SCOPE OF WORK Planning Atlas will schedule field personnel and equipment, notify Underground Services Alert to locate underground utilities as required, and perform other necessary field preparation and job start-up activities. A private utility locating service will also be used to locate underground utilities that may be present in the work areas. A drilling permit application will be completed and submitted to the San Joaquin County Environmental Health Department (SJCEHD) prior to initiation of drilling activities. Atlas will submit an encroachment permit to the City of Stockton in order to obtain off- site access for the proposed off-site drilling locations. Atlas will require authorization from any off- site property owner prior to conducting drilling activities. Off-site Groundwater Assessment Groundwater monitoring wells associated with the subject site (Figure 3) are generally screened in multiple zones: shallow, intermediate, and deep. MW 1, MW2, MW3, MW8, MW9, MW 10, MW11 Rare screened from approximately 45 to 68 feet bgs, MW13 and MW14 are screened from approximately 45 to 60 feet bgs, and MW 16 and MW 17 are screened from approximately 40 to 59 feet bgs. These wells constitute the shallow groundwater zone monitoring wells. MW4, MW5, MW6, MW 12, MW 18, and MW 19 are screened from approximately 85 to 90 feet bgs in the intermediate zone. MW7 is screened from approximately 116 to 121 feet bgs and MW15 is screened from approximately 141 to 151 feet bgs.Well construction details are presented in Table 1. Based on recent subsurface investigation activities conducted at the site, the shallow groundwater plume appears to be adequately defined in all directions with regard to the California State Water Resources Control Board's Low Threat Underground Storage Tank Case Closure Policy(Policy). The intermediate groundwater plume appears to be generally defined, except to the east, with regard to the Policy. The groundwater gradient in the intermediate zone is typically very flat resulting in variability with regard historical groundwater flow direction. In order to further evaluate the lateral extent of the intermediate groundwater plume, two soil borings are proposed to be advanced east of the site; one in the western right-of-way of Grattan Avenue and another in the northwestern portion of 2150 East Fremont Street at the approximate locations shown on Figure 3. Atlas anticipates the borings will be installed in the sidewalk or the roadway depending on the potential presence of utilities and municipal requirements. The two proposed soil borings will be advanced using cone penetration test(CPT) methods. CPT borings are proposed in lieu of monitoring wells as a cost saving measure. Drilling will be 41