ARCHIVED REPORTS XR0011146 - Laserfiche WebLink

Home Browse Search

i lie 03 October 2000 AGE-NC Project No 97-0326 IPage 2 of 5 3 1 PROBING AND SAMPLING i On 10 April 2000, two soil probe borings (probmgs) were advanced at the site using AGE's Geoprobe 5400 probing unit equipped with 1 25-mch diameter probe rods and a 2 15-mch diameter soil sampling assembly Both probe borings were advanced to a vertical depth of 70 feet Probing locations are shown on Figure 2 Soil samples were collected at intervals of 5 vertical feet, beginning at a depth of 20 feet below surface grade (bsg)in the boring advanced through the conductor casing(13-5), and beginning at 45 I feet in the boring near MW3 (B-6), to the total depth of each boring In accordance with the work plan addendum dated 10 September 2000, the borings were advanced until two consecutive soil samples were free of field rnchcations of hydrocarbons All samples were collected using the IGeoprobe soil sampling assembly loaded with four 1 125-Inch by 6-inch brass sleeves After collection, the ends of the second brass sleeve were covered with Teflon sheets,capped and sealed with tape The sleeves were labeled, placed in a chilled container and selected samples were transported to Alpha Analytical Laboratories, lnc (AAL)in Ukiah under chain-of-custody A total of 14 soil samples were analyzed for total petroleum hydrocarbons quantified as gasoline (TPH-g) • m accordance with method GCFID 5030A, and for aromatic hydrocarbons - benzene, toluene, ethylbenzene and xylenes(BTEX)with metbyl tertiary-butyl ether(MTBE)In accordance with EPA method 8020, or BTEX with five oxygenates in accordance with EPA method 8260B A grab ground water sample was collected from each boring at total depth (70 feet bsg 1n both borings) using a Geoprobe water sampling assembly, by advancing the ground water sampling I assembly to 70 feet and retracting the steel housing to expose 4 feet of screened PVC casing Water was retrieved using a positive-displacement sample tubing and ball-bearing assembly The ground water samples were collected into 40-m1 VOA vials, labeled, placed in the chilled container, and transported along with the soil samples to Alpha Analytical Laboratories, Inc under chain-of- custody All probing rods,sampling tools and sample liners used for sample collection were thoroughly rinsed with clean water after washing with a solution of Alconox between each sampling nun Both borings were backfilled over their entire depth with portland cement 3 2 LOGGING Soil was extruded from the remaining brass sleeves and screened for the presence of organic vapor using an organic vapor meter equipped with a photo-ionization detector (PID Thermo Environmental 580A, 10 OeV, calibrated to isobutylene), and the readings were recorded on the . boring logs The soil sample duplicates were visually described in accordance with the Unified Soil Advanced GeoEnviranme&4Inc- A