SITE INFORMATION AND CORRESPONDENCE_FILE 2

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Site Background Information: Chapin Brothers Investments, Inc. Page 8 of 19 REMEDIATION WELL INSTALLATION On 29 July 1997, three in-situ air-sparing (IAS) points (IAS-7 through IAS-9) were installed to depths of 25 and 15 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 25 feet bsg to an anchor tip. One additional probe boring was completed using one 21-inch long, 3/8-inch I.D. stainless steel screen implant set at a depth of 15 feet bsg. 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 20 to 25 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. SOIL VAPOR EXTRACTION - MASS OF RECOVERY In-situ air sparging (IAS) and soil vapor extraction operated on the site for approximately eight quarters. Over this period a calculated minimum of 409 gallons of gasoline have been removed. A population of biodegrading micro-organisms exists on the site that promotes degradation of the hydrocarbons.These organisms were not detected in the off-site sample analyzed(December 1998). The soil vapor extraction progress on the site removed approximately 397 gallons of gasoline or 2,480 lbs of TPH-g. MONITORING WELL INSTALLATION On 01 April 1998, soil boring MW-7 was advanced on the property directly east of the site. The boring location is illustrated on Figure 2. The soil boring was advanced to a depth of 25 feet bsg. Boring MW-7 was completed as a ground water monitoring well.The well was completed using 2- inch diameter schedule 40 PVC casing with 0.02-inch slotted screen from approximately 5 to 25 feet bsg.A filter pack was installed using#2 Lonestar sand from 4 to 25 feet.Bentonite chips were used to make a two-foot plug and the remaining annular space was backfilled to the surface with portland cement.A traffic-rated well box(8-inch diameter)was installed over each well,in accordance with County regulations. Soil samples collected from depths of 15,20 and 25 feet bsg were analyzed and were non-detect for petroleum hydrocarbons. Advanced GeoEmironmental,Inc.