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30 January 2014 AGE Project No . 99-0682 Page 5 of 28 and CPT4with maximum concentrations detected in the groundwater samples from CPT-3 as high as 9, 300 tag/I benzene and 49 , 000 pg/I toluene in HUB, and 5,500 tag/I ethylbenzene and 25 , 500 tag/I total xylenes in HU9/10 . 1 ,2-DCA was detected in the water samples collected only from CPT-3 at concentrations of 37 pg/1 in HU8 and 23 tag/I in HU9/10 . January 2006 - One soil boring was advanced and two deep groundwater V monitoring wells (MW-1 C and MW- 1 D ) were installed at the site. A CME-95 truck- mounted drill rig was utilized to advance soil borings B-4, MW-1C and MW-1D to total depths of 150 feet below surface grade (bsg ), 135 feet bsg and 150 feet bsg , respectively, using 8-inch diameter hollow-stem augers . Soil samples were not collected in borings MWA C and MWA D . No soil samples were collected in boring B-4 until 50 feet bsg . Pilot borings MWAC and MW-1D were completed as groundwater monitoring wells of the same designations using 2-inch diameter polyvinylchloride ( PVC) casing with 0. 010-inch slotted screen installed from 125 feet to 135 feet bsg and 140 to 150 feet bsg , respectively. TPH-g was detected in the soil samples collected from B-4 at 60 feet, 70 feet, 90 cOAy , ' feet, 100 feet, 130 feet and 149 feet bsg . Concentrations ranged from 2 . 0 mg/kg t� t� (134- 100) to 2 , 500 mg/kg (134-70). BTEX constituents were detected in the boring B4 %P, L,t samples from 60 feet, 80 feet, 90 feet, 130 feet and 149 feet. Maximum concentrations were detected in sample 134-70 at 4 .7 mg/kg benzene , 32 mg/kg toluene , 7. 9 mg/kg ethylbenzene and 45 mg/kg xylenes . January 2006 - Soil boring CPT-5 was advanced off-site , at 540 North California Street utilizing CPT technology to model the geologic and hydrogeologic framework and to assess potential dissolved petroleum migration from the site . Lithologic data was collected from an initial CPT soil boring ; adjacent borings were then advanced to collect grab groundwater samples from selected depths . Soil boring CPT-5 was advanced to a total depth of 200 feet bsg . Groundwater samples were collected from the CPT boring at the following intervals : 59 to 63 feet bsg , 72 to 75 feet bsg , 104 to 108 feet bsg , 117 to 121 feet bsg , and 171 .5 feet and 174 . 5 feet bsg . Additionally, soil probe borings P-521 - 1 , P-521 -2 and P-521 -3 were advanced off- site at 521 East Oak Street, the dirt parking area to 537 East Oak Street, utilizing a van-mounted Geoprobe 5400 direct-push probing unit. All borings were advanced to 44 feet bsg , and a grab groundwater sample was collected at total depth of each boring . No analytes of concern were detected in the grab groundwater samples collected from CPT-5 and probe borings P-521 - 1 , P-521 -2 and P-521 -3 . jApril 2007 - Two groundwater monitoring wells (MW-7 and MW-8) and four vapor extraction wells (VW- 1 through VW-4) were installed at the site . Pilot borings VW-1 and VW-3 were completed as vapor extraction wells with slotted screen installed from approximately 20 to 30 feet bsg ; pilot borings VW-2 and VW4 were completed Advanced GeoEnvironmental, Inc.