Laserfiche WebLink
�. •.+► <br /> Historical Background Information: West Clay Properties <br /> Page 2 of 7 <br /> October 1999 - Seven soil borings (B-10 through B-16) were advanced to collect and analyze soil <br /> samples; in addition, one soil sample collected from boring B-11 was analyzed for permeability, <br /> porosity, total organic content and specific gravity. Petroleum hydrocarbon-impacted soil was <br /> detected in soil samples collected from all soil borings except B-13;the highest concentrations were <br /> detected in soil samples collected from boring B-10, located adjacent to the former UST No. 3 <br /> excavation. <br /> July 2001 -An 8-hour step draw-down ground water extraction pilot test was conducted at the site. <br /> High concentrations of petroleum hydrocarbons were detected in extracted ground water samples. <br /> November 2004 - Based on the results of the July 2001 pilot test, a 24-hour constant rate ground <br /> water extraction feasibility test was performed at the site. Detected concentrations of target analytes <br /> in extracted ground water samples were significantly lower than those reported for the July 2001 <br /> pilot test. <br /> Ground Water Monitoring - Based on analytical results of ground water samples collected during <br /> quarterly monitoring and site assessment activities, the lateral extent of impacted soil has been <br /> defined to the north,east and west.However,the vertical extent of the contamination plume,as well <br /> as the lateral extent to the south, is not well defined. <br /> Cluster UST Area (North Area) <br /> December 1998 - Two 10,000-gallon USTs and one 6,000-gallon UST were removed from a <br /> common excavation at the site. <br /> October 1999-AGE advanced one soil boring(B-9)for collection of soil and ground water samples. <br /> Significant concentrations of petroleum hydrocarbons were detected in samples collected from the <br /> boring. Based on the findings from boring B-9,monitoring wells MW-9 and MW-10 were installed <br /> near the former UST excavation area. <br /> July 2000 - Nine pilot borings were advanced at the site for installation of monitoring wells <br /> MW-11A/B through MW-13A/B, air-sparging well AS-1 and ground water extraction wells EW-1 <br /> and EW-2.Petroleum hydrocarbons were detected in soil samples collected from pilot borings EW-1 <br /> and MW-13B. <br /> November 2002 - Four pilot borings were advanced at the site for installation of monitoring wells <br /> MW-14AB and MW-15A/B. Target analytes were not detected above laboratory reporting limits <br /> in the soil samples submitted for analyses. <br /> Advanced GeoEnvironmental.Inc. <br />