Laserfiche WebLink
02 June 1997 <br /> AGE-NC Project No 95-0105 <br /> ' Page 10 of 11 <br /> ' extent of the plume as probably close the mirror image of the eastern extent as,delineated by <br /> MW-5, assuming well MW-4 is located at the center of the plume center <br /> ' • After a period of at least 10 years since the hydrocarbon release occun ed, the leading edge <br /> of the dissolved plume has not migrated to the down gradient monitoring wells, well MW-6 <br /> and the City of Tracy Fire Department monitoring well, demonstrate a degree of plume <br /> stability of the down-gradient extent of the plume <br /> • Soil accumulated from the installation of the monitoring well has been disposed of at an <br /> ' appropriate disposal facility <br /> • A well survey was conducted to gather information regarding the location and use of <br /> municipal and domestic wells within 2,000 feet of the site No active,domestic ground water <br /> ' wells were found within the search range <br /> ' 7 0. RECOMMENDATIONS <br /> Based upon data collected at the site, AGE recommends the following <br /> • Petroleum hydrocarbon-impacted soil remain near the northwest end of the June 1995 <br /> ' excavation limits and in the central portion of the site Hydrocarbon-impacted soil both on- <br /> site and off-site is not easily accessible, due to being located under the structures (i e <br /> roadway, building and canopy) associated with the site AGE does not recommend active <br /> ' remediation of the remaining petroleum hydrocarbon-impacted soil, due to these logistical <br /> constraints <br /> ' • Concentrations of dissolved hydrocarbons have remained stable or declined in the area of the <br /> impacted monitoring well on the site and the dissolved hydrocarbon plume appears to be <br /> stable within the constraints of the monitoring well locations Therefore AGE recommends <br /> ' no further sampling of the ground water wells <br /> • Based on the limited use of shallow ground water in the Tracy area, the apparent stable <br /> ' nature of the dissolved hydrocarbon plume and possible declining concentrations`of the <br /> dissolved hydrocarbons, the WT Jordansite appears to qualify as a"low-risk ground water <br /> site" Therefore certified closure should be considered for the site ` <br /> ' Upon closure certification, all monitoring wells should be abandoned and destroyed an <br /> accordance with the local regulations <br />