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Following completion of borings VEAS-1, VEAS-2, and VEAS-3 the borings were completed as dual completion vapor extraction/air sparge wells The VEAS-1 through YEAS-3 well borings were drilled to approximately 65 feet below ground surface The vapor extraction porton of the wells were constructed of a 4-inch PVC casing VEAS-1 and VEAS-3 were screened from 15 to 50 feet, and YEAS-2 was screened from 10 to 50 feet, all with 0 020 factory slots The air sparge portion of the wells were constructed of 63 feet of 1-inch Schedule 80 PVC with stainless steel air sparge points, screened with 0 020 factory slots from 63 to 65 feet bgs Remediation well construction details are presented in Table 2, Well Construction Details, and are illustrated in Figure 7, Remediation Well (VEAS-1 and VEAS-3) Construction Detail, and Figure 8, Remediation Well (VEAS-2) Construction Detail The annulus of the screened portion of the vapor extraction and air sparge wells were backfilled with a#3 Monterey sand (or equivalent) filter pack from approximately 14 to 50 feet (9 to 50 feet bgs for VEAS-2), and from 63 to 65 feet bgs Hydrated bentonite was placed from 12 to 14 feet bgs (7 to 9 feet bgs in ' VEAS-2), and from 60 to 62 feet bgs Bentonite grout was placed from 50 to 60 feet and from 6 to 12 feet bgs (6 to 7 feet bgs In VEAS-2) The remaining annular space to the surface (approximately 4 feet) was filled with neat cement grout The wells were completed from 2 feet bgs to the ground surface with a ' watertight, flush-mounted, traffic-rated vault and set in a 2-foot concrete perimeter seal All well casing and screen was delivered to the site new, in factory-sealed containers ' Following groundwater monitor well, and groundwater extraction well completion, MW-13 through MW- 17, and EX-1 were developed by a combination of surging and bailing groundwater from the wells Approximately 35 gallons of purge water was generated during development of each of the groundwater rmonitor wells (NIW-13 through MW-17), and approximately 150 gallons of purge water was generated during the development of the groundwater extraction well (EX-1) Groundwater purged from the wells ' was contained in properly labeled DOT-approved 55-gallon drums and stored on-site pending proper disposition The groundwater monitoring wells were installed and developed an general accordance with ATC's Standard Operating Procedure - Soil Borehole Drilling, Monitor Well installation and Development, ' and Soil Sampling,which is included in Appendix C A California-licensed land surveyor surveyed the Iocation and elevation of existing wells MW-1 through ' MW-12, VW-1 through VW-3, and the location and elevation of the newly installed groundwater monitor wells, MW-13 through MW-17, to a City of Stockton benchmark (Benchmark No 63, Elevation = 20 87 ' feet above mean sea level) The location and elevation of measuring marks at each well-head were surveyed to the nearest 0 01 foot by the licensed surveyor In order to more accurately determine the local groundwater flow direction beneath the site relative to mean sea level In addition, in accordance with Article 12 (Section 2729 1) of Chapter 16, Division 3, Title 23 of the California Code of Regulation (CCR), the latitude and longitude of each groundwater monitor well was measured to an accuracy of one meter A copy of the survey data is included in Appendix D EZ 100966ASAR rpt ATC Associates Inc 11San Diego\EZ Serve11009661Reports1100966SAR00I rpt ATC Project No 43 25827 0026 9