FIELD DOCUMENTS - Laserfiche WebLink

Home Browse Search

14 June 2004 AGE-NC Project No. 04-1180 Page 4 of 5 3.4. GRAB GROUND WATER COLLECTION AND ANALYSIS After probing to a depth of 50 feet bsg,ground water was encountered at between 40 and 50 feet bsg. A `grab' ground water sample was collected from each boring. The ground water sample was 1.. extracted by lowering an inertia pump down a temporarily installed,one-inch diameter PVC casing with a 1.0-foot long, 0.01-slotted well screen at the lower end. Each ground water sample was transferred into three laboratory-supplied, 40-m1 volatile organic analysis (VOA) vials containing 0.5 ml hydrochloric acid(18%) as sample preservative. After collection,the samples were properly labeled,placed in a chilled container and transported under chain-of-custody to CTEL. The samples were analyzed for the same petroleum hydrocarbon products listed in Section 3.2. 4.0. FINDINGS The stratigraphy and ground water hydrogeology underlying the site was characterized.from the field. descriptions.Hydrocarbon impact to the soil and ground water,was assessed by laboratory analysis. 4.1. STRATIGRAPHY In general, brown sandy-silts were.encountered from surface grade to depths of approximately 20 feet bsg; brown silty-sands and sandy-silts were encountered from depths of 20 to 50 feet bsg. Samples were moist to saturated starting at 40 to 45 feet.bsg and in general, had low.plasticity, toughness and consistency.Field observations did not detect petroleum hydrocarbon-like odor in any of the soil samples collected. Organic vapors were detected in soil samples from both borings beginning at depths of 30 feet bsg. Boring logs are included as Appendix D. V - 4.2. LABORATORY ANALYSIS OF SOIL AND GROUNDWATER SAMPLES Three soil samples and two groundwater samples were submitted to CTEL for analysis. Total petroleum hydrocarbons quantified as gasoline were detected in the groundwater sample from boring P1 ("P1-W") at a concentration of 140 micrograms per liter:gg/1(parts per billion).No other target analytes were detected in the analyzed soil or groundwater samples.A copy of the laboratory report (CTEL Laboratory Project Number CT214-0406010) is included in Appendix E. Advanced GeoEnviron mental,Inc.