ARCHIVED REPORTS XR0011176 - Laserfiche WebLink

Home Browse Search

REMEDIATION TESTING AND DESIGN March 12 , 1993 ` pipe Each probe will contain a 36-inch range of 3/16-inch drilled perforations at one end with a forged point All probes will be steam cleaned prior to use They will be hydraulically driven t,7 a depth of , but not more than, approximately twenty feet below ground surface Depths of probes will be determined in the field by the ' registered geologist from RTD and by a representative of Ultr&mar , Inc based on past boring log data Following installation, a pump induced vacuum will be applied tD each probe to purge resident soil gas Sample purge rates and vacuums will be monitored and recorded for each probe . Soil gases from the probes will be analyzed for total volatile hydrocarbons ( TVH) using an organic vapor analyzer (OVA) or a flame ionization detector (FID ) In addition, RTD will collect soil gas samples in one liter Tedlar bags from up to five probes to be sent to a certified laboratory for analysis of total petroleum hydrocarbons as gasoline (TPHg ) and benzene , toluene, ethylbenzene and total xylenes ' BTEX) The soil gas TVH data will be mapped on a scaled site plan to aid in the evaluation of gasoline source areas and migration pathways . Upon completion of the SGS , the probes will be used for the VEFT Following the VEFT, certain probes will remain in the ground to be utilized in a vacuum extraction remediation system. The probes that will be removed will have the probe holes sealed with portland cement slurry The probes left in the ground for the vacuum i extraction system will be capped by RTD prior to RTD leaving the site Ultramar , Inc. contractors will , within one week, connect the probes to lateral piping, provide a sanitary seal and cover each probe with a vault box with a locking lid They have also stated that there will be a permanent six foot fence surrounding the property RTD and Ultramar have extensively discussed the limitations and potenta..al dangers associated with driving temporary probes. Given these limitations , Ultramar, as our client and site owners , is entirely responsible for selecting probe locations . All probes driven by RTD will be at the direction of Ultramar. RTD reserves the right to refuse to drive any probes, at its sole discretion. Vacuum Extraction Feasibility Testing A VEFT using the existing on site monitor wells , vapor recovery wells and temporary probes will be conducted to determine the effectiveness of using vacuum extraction for remediation of soils , ' groundwater and removal of insoluble hydrocarbons ( if present) f _ RTD anticipates conducting short extraction tests with numerous wells and probes on the first day following the soil gas survey Based on the flow characteristics in the wells and probes , two or three will be used as extraction points for a full day of testing The VEFT will be conducted in two to three segments for a full day Df extraction The first segment will consist of applying an 2