ARCHIVED REPORTS XR0003996 - Laserfiche WebLink

Home Browse Search

' 12 June 1996 AGE-NC Project No 95-0112 Page 2 of 7 1 Since October 1992, ground water has been sampled and analyzed on a quarterly basis Petroleum hydrocarbon concentrations have fluctuated in most wells since 1992 All wells have shown a decrease in hydrocarbon concentrations in each quarter since July 1995 Past and current analytical results of ground water samples are included in Table 3 23 SOIL AND GROUND WATER REMEDIATION ' In anticipation of soil remediation at the site, boring RW-1 was installed in August 1993 Boring RW- 1 was drilled at a 15° angle from vertical from a surface location near the southeast corner of the building, and completed as a 4-inch diameter remediation well A Final Remedial Plan (FRP)was then prepared by Geological Audit Services, Inc (GAS) in July 1994, outlining soil and ground water remediation procedures for the site ' In May 1995, in-situ air sparging wells SW-1 and SW-2 were installed at the site Subsequently, in July 1995, a soil vapor extraction/in-situ air sparging (SVE/IAS) system was installed inside a fenced enclosure at the southeast corner of the Art & Artists building The operation of the remediation system began in August 1995 3.0. PROCEDURES 3 1 DRILLING AND SAMPLING 1 On 13 March 1996 two boringswere advanced at the site Borings B-9 and B-10 were advanced to depths of 60 feet using a truck-mounted CME-75 drill rig The drill rig and two-man crew were supplied by Soils Exploration Services, Inc (SES) of Benicia, California Boring Locations are illustrated on Figure 2 Boring locations were approved by Ms Mary Meays of the PHS-EHD prior Ito advancement Soil samples were collected ahead of the drill bit using a split-tube sampler loaded with three pre- cleaned 2-inch by 6-inch brass sleeves Samples were collected at five-foot intervals, beginning at 15 feet,using a 140-pound hammer to advance the sampler 18 inches The number of blows required to advance the sampler in 6-inch increments was recorded on the boring logs Samphng equipment was washed in an Alconox solution and rinsed with water prior to each sampling - run to avoid cross-contamination Augers were steam-cleaned between borings Auger returns were 1 placed in 55-gallon DOT drums and stored on-site Each soil sample collected for analysis was preserved in the lead brass sleeve by covering both ends of the sleeve with Teflon sheets, capping and sealing with tape Samples were labeled, stored on ice