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1,000-gallon UST used to store gasoline,and one 500-gallon UST used to store gasoline (Gallardo, 1999). During the removal of the USTs,site soils containing petroleum hydrocarbons were observed. Gallardo and Associates (Gallardo)performed an initial site investigation on March 23 and 24,1999. The investigation included installation of five soil borings(B-1 through B-5) in the vicinity of the removed USTs. The soil borings extended to a maximum depth of 40 feet Below Ground Surface (BGS). Analytical results of soil samples collected indicated the presence of TPHD;and Total Petroleum Hydrocarbons as Kerosene (TPHK) and as Gasoline(TPHG). Additionally,Benzene, Toluene, Ethylbenzene,and total Xylenes (BTEX)constituents were detected in select soil samples. The maximum depth of soil containing petroleum hydrocarbons was estimated to be 35 feet BGS. ` Methyl Tertiary-Butyl Ether (MTBE)was not detected in any of the soil samples analyzed. One Lgroundwater sample was collected from soil boring B-4. Petroleum hydrocarbon constituents were detected in the groundwater sample;however,MTBE was not detected. In December 2000 and January 2001, D.K. Barber P.E. and Associates (Barber) and Stellar Environmental Solutions (SES) installed six soil borings (C-1,-2,-3,-4/6,-5/7,and MW-1),two temporary well points (C-4/6 and C-5/7),and one groundwater monitoring well (MW-1) at the site. The soil borings and temporary well points were installed using a Direct Push Technology (DPT) drill rig. Soil and groundwater suspected of containing TPHD and TPHK was observed k during the investigation. ` In June 2002,five additional monitoring wells (MW-2 through MW-6) were installed in the vicinity of the site using a hollow stem auger drill rig. Additionally,soil boring temporary well point D-3 was installed in June 2002. Soil samples were collected during the installation of the monitoring wells and soil boring in approximate 5-foot intervals. One groundwater sample was collected from the well point installed in soil boring D-3. Groundwater samples were collected from the Lmonitoring wells following well development. Analytical results indicated detectable levels of TPHD,TPHK,and BTEX constituents in site soil and groundwater. LIn November 2003, Barber oversaw the installation of six temporary well points (HP-1 through HP-6)using a DPT drill rig equipped with Cone Penetration Technology (CPT). The well points were installed using a Hydropunch®sampler. No soil samples were collected. CPT data was collected during the installation of CPT/HP-1 and CPT/HP-3. Groundwater samples were collected from all six temporary well points. TPHD was detected in groundwater from four of the six well points installed. In January 2004,Barber and WOS personnel installed seven exploratory trenches in the vicinity of the former UST and AST area. Exploratory trenches were installed to a maximum depth of 14 feet BGS. Groundwater was not encountered. Soil samples were collected at multiple depths and submitted for laboratory analysis(E-1,E-2,E-3,E-3N,E-4,E-5E,and E-5W). TPHMO and TPHD t were detected in soil samples collected from all exploratory trenches. In May 2004,Barber oversaw the installation of nine additional Hydropunch®well points (HP-7 through HP-15) to further characterize the lateral extent of petroleum hydrocarbons in groundwater. The well points were installed to the east and north of the site. One groundwater sample was collected from each well point. TPHD was detected in groundwater samples collected from four of the nine well points. \\Eureka\projects\2007\007152-WOS\PUBS\rpt\20100324-1stHa1f2010GWMR&RFC.doc 5