ARCHIVED REPORTS_XR0003230 - Laserfiche WebLink

Home Browse Search

Ct� I NVV/r, i A S S O C I A T E S I N C monitoring wells and two of the soil borings were completed as vapor extraction wells The soil boring, groundwater monitoring well, and vapor extraction well locations are shown on Figure 2 On July 3, 1997, the monitoring wells were developed and sampled for petroleum hydrocarbons along with the adjacent property owner's well (CW) The samples from wells MW1, MW2, and MM3 contained concentrations of total petroleum hydrocarbons as gasoline (TPHg) and benzene ranging from 3,200 parts per billion (ppb) to 130,000 ppb and 920 to 11,000 ppb, respectively Field activities and analytical results were detailed in Smith Technology's ,Summary Report dated September 17, 1997 The report contained recommendations for the installation of additional soil borings and groundwater monitoring wells to fully delineate the vertical and horizontal soil and groundwater contamination PHS/EHD agreed with these recommendations with minor modifications in correspondence dated November 13, 1997 SAMPLING ACTIVITIES On December 23, 1997, groundwater samples were collected by ATC Associates personnel from monitoring wells MW 1, MW2, MW3, and CW The locations of the monitoring wells are shown on Figure 2 Prior to collection of groundwater samples, the depth to water, pH, electrical conductivity, and temperature were measured in the monitoring wells and recorded A minimum of three well casing volumes were purged from each well prior to sampling The wells were allowed to recover and samples were collected from each well using dedicated disposable bailers The groundwater samples collected from each well were submitted to State-certified American Environmental Network (AEN) laboratory (DOHS Cert No 1172) for chemical analysis of TPHg, benzene, toluene, ethylbenzene, and xylenes (BTEX) utilizing EPA methods 8015/8020, oxygenate fuel additives utilizing EPA method 8260, and lead Groundwater well purge and sample logs are contained in Attachment 1 ANALYTICAL RESULTS TPHg and BTEX were detected above laboratory method detection limits in the samples collected from wells MW1, MW2, and MW3 The sample collected from well CW contained only toluene above the method detection limit Oxygenate fuel additives were not detected in any well, although the samples from wells MW1, NIW2, and MW3 had higher detection limits due to dilution factors Lead was not detected in any of the groundwater samples A summary of analytical results is presented in Table 1 Laboratory data sheets and chain-of-custody documentation are contained in Attachment 2 GROUNDWATER FLOW DIRECTION Water level measurements were collected from wells MW-1, MW-2, MW-3, and CW on December 23, 1997 Water levels ranged from 28 26 to 28 96 feet below the tops of the well w\977311quafliyl4gr-1997 doe 2