SITE INFORMATION AND CORRESPONDENCE_FILE 2

Home Browse Search

Site Background Information: Chapin Brothers Investments, Inc. Page 5 of 19 REMEDIATION WELL INSTALLATION On 19 April 1997,one additional SVE well, VW-7 was installed at the eastern edge of the site to a depth of 15 feet. Also six in-situ air-sparing (IAS) points point were installed using two 21-inch long, 3/8-inch I.D. stainless steel screen implants attached to an anchor tip at 30 feet bsg. (IAS-2 through IAS-7)were installed to depths of 30 feet bsg using AGE's van-mounted Geoprobe 5400 soil probing machine.Two probe borings were completed as IAS points using one 21-inch long,3/8- inch I.D.stainless steel screen implant attached at 26 feet bsg to an anchor tip.Vinyl tubing(3/8-inch O.D.) was extended from the sparging screen implant to the surface and a filter pack (fine glass beads)was installed around the screen implant from a depth of 25 to 30 feet bsg.Bentonite sand(#8 bentonite)was used to make a 4-foot plug above the filter pack and the wells were grouted to surface grade with portland cement.An eight-inch traffic box was installed at the surface for each IAS point. On 24 April 1997,monitoring well MW-6 was installed northwest across Mt Diablo Avenue from the site; adjacent to the Victory Elementary School. Soil samples were not impacted. SOIL VAPOR EXTRACTION SYSTEM INSTALLATION On 04 March 1997,a King,Buck/Hasstech(KBH)(90-032)catalytic oxidation unit(SVE unit)was delivered to the site. The extraction equipment was placed inside a fenced enclosure near the west end of the site. Replacement parts for all missing or broken items were purchased and installed.On O1 April 1997, the natural gas service to the SVE unit on the site was upgraded to 5 pound of pressure per square inch, the minimum pressure required to operate the KBH catalytic oxidation system. The existing network at the site consisted of subsurface flex piping from wells VE-2, VE-5, VE-6 and MW-4 to the remediation unit enclosure.AGE installed additional subsurface piping from wells VE-1, VW-1 and VW-7. The piping was then routed through a moisture knockout drum to a 5- horsepower, 200 cubic feet/minute (cfm)regenerative blower and into the KBH catalytic oxidizer oven.AGE installed an in-line flow meter after the blower motor as well as sampling ports before the knockout drum,between the oven and after the oven to monitor the concentration of extracted hydrocarbons and efficiency of hydrocarbon destruction. SOIL VAPOR EXTRACTION START-UP AND UTILITY UPGRADES The KBH catalytic oxidation SVE system began full-scale operation on 01 April 1997.The SVE unit operated at a maximum flow rate for approximately for three hours.At approximately 1800 hours on 01 April 1997,the 60 amp power service at the PG&E service connection to the site failed.The power demand of the SVE unit was greater than the service connection could supply. A new 100 Advanced GeoEnvironmental.Inc.