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On November 20, 2012, Cardno ATC(now ATC)oversaw the advancement of a CPT boring CPT-1 to a total depth of 100 feet bgs. A soil sample was collected from 68 to 69 feet bgs and a groundwater sample collected from 76 to 80 feet bgs. Based on the soil logging, a confining unit is presumed to be located at 68 feet bgs, and the soil sample from this location did not have any detectable hydrocarbon concentrations. A soil sample was also collected from 69 feet bgs and analyzed for physical properties for any future modelling.The groundwater sample reported TPHg at 1,100 pg/L,toluene at 0.64 µg/L, MTBE at 4,800 µg/L,TAME at 4.7 pg/L, and TBA at 1,000 µg/L. On January 25, 2013, soil gas samples were collected from VP-1 through VP-3. None of the soil gas samples exceeded the regional soil screening levels for industrial scenarios and no residential structures are present on-site or on adjacent properties. In June 2016,ATC oversaw the installation of off-site monitoring well MW-10 to an approximate depth of 65 feet bgs. Petroleum hydrocarbons were not detected in soil and groundwater samples collected from off-site monitoring well MW-10. In April 2017,ATC oversaw the installation of on-site monitoring wells MW-11 to MW-14 and one soil boring B-12. Monitoring well MW-11 was installed at a depth of 60 feet bgs and monitoring wells MW- 12 through MW-14 were installed at a depth of 80 feet bgs. Soil boring B-12 was advanced to a depth of 20 feet bgs. Petroleum hydrocarbons were not detected in soil samples collected from MW-11, MW-12, and B-12. Petroleum hydrocarbons were detected at very low concentrations in soil samples collected from on-site monitoring wells MW-13 and MW-14. In January 2018, ATC field staff supervised the installation of two offsite monitoring wells, MW-15 and MW16 at offsite locations northeast and east of the property. Monitoring wells MW-15 and MW-16 were installed at a depth of 55 feet bgs. Petroleum hydrocarbons were not detected in soil samples collected from MW-15 and MW-16. Development of the monitoring wells occurred in May 2018, where upon ATC discovered that MW-16 had collapsed onto itself at the measured depth of 45 ft bgs. MW-16 was re-drilled on August 9, 2018. On August 8, 2018, ATC oversaw the advancement of a CPT boring CPT-2 to a total depth of 65 feet bgs. The boring was advanced offsite to the north in lieu of a monitoring well due to access limitations. One groundwater sample was collected at approximately 61 feet bgs. The groundwater sample was analyzed for TPPH (a.k.a.TPHg), BTEX, MTBE, ETBE,TBA,TAME, DIPE, EDB, 1,2-DCA, ethanol, and naphthalene. None of the analytes were detected in the groundwater sample collected from boring CPT-2. SCOPE OF WORK Well Destruction Activities The current groundwater monitoring well network consists of eleven on-site wells (MW-1 through MW- 7, and MW-11 through MW-14), and five off-site wells located west, northwest, northeast and east of the site (MW8 through MW-10, MW-15 and MW-16). There are three soil vapor wells on-site (SVE-1 through SVE-3) and one air sparge well (AS-1). The monitoring wells are screened between 40 and 80