Laserfiche WebLink
Stallworth Auto Detail - . 3 - April 2012 <br />'l Site History/Assessments <br /> In May 1991 , soil contamination was identified during the removal of USTs. To date, 14 <br /> monitoring wells have been installed and monitored regularly. A Site map showing the location <br /> of the former USTs, monitoring wells and groundwater level contours is provided at the end of <br /> this five year summary. <br /> Remediation Summary <br /> • Free Product: No free product was documented throughout the life of this case . <br /> • Soil Excavation : Unknown . <br /> 1 • In-Situ Soil Remediation : Soil vapor extraction , conducted from September 2010 <br /> through present removed approximately 10, 201 pounds of TPHg . In October 2011 , the <br /> rate of removal was 1 . 3 pounds of TPHg/day. <br /> • Groundwater Remediation : In-situ chemical oxidation proposed . <br /> General Site Conditions <br /> • Geology and Hydrogeology: The Site is underlain by interbedded and intermixed sand , <br /> silt and clay. The depth to groundwater varies between 26 and 28 feet bgs and the <br /> groundwater gradient is northeast to east at approximately 0 .005 ft/ft. <br /> • Groundwater Trends : There are more than 11 years of groundwater monitoring data for <br /> this Site. Benzene trends are shown below, source area (MW-8) , near down gradient <br /> (MWJ and MWA 1 ) and far down gradient (MW- 10) <br /> Benzene Trend for MW-8 <br /> 25000 <br /> . 20000 <br /> ,? 15000 <br /> p <br /> 10000 -- - - <br /> m <br /> 5000 -- <br /> 0 — --- <br /> h I� R CpO W Ol Opp gl o o O .i <br /> O O O S o O O O O O O O O o <br /> Benzene Trend for MW-7 <br /> 4000 - - - - - - - <br /> 3500 46 <br /> 3aoo t_ _20001-900Joao500 <br /> o <br /> o 0 o <br /> o g g o 0 0 0 0 0 <br /> a ao <br />