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(YVATC <br /> A S S O C I A T E 5 I N C . <br /> SCOPE OF WORK - METHODOLOGY <br /> The proposed scope of work herein has been prepared to address subsurface environmental <br /> concerns at the Bank of America property located at 1661 Pacific Avenue. Specifically these <br /> concerns include off-site migration of petroleum hydrocarbons from the former Unocal service <br /> station (located immediately to the north of the site), and impaction from a former dry cleaners <br /> and paint facility (located on the southeastern portion of the property). <br /> In brief, the proposed work includes performing a limited soil gas survey and collecting <br /> confirmation groundwater samples to document current subsurface conditions beneath the site. <br /> A description of the proposed work is explained in detail in the following paragraphs. <br /> Soil Gas Survey <br /> ATC will perform a limited soil gas survey of the site's suspect areas including the northeastern <br /> portion of the subject property bounding the former Unocal site and the former on-site dry <br /> cleaners and paint establishment on the southeastern portion of the property. Direct push <br /> technology developed by Transglobal Environmental Geochemistry (TEG) will be employed to <br /> advance soil gas probes to desired depths where soil gas will be extracted and sampled. In areas <br /> of the property, which offer only limited access, hand tools will be utilized to drive the gas <br /> collection probe to desired depths. <br /> It is anticipated that a minimum of eight soil borings will be advanced at the site to a depth of <br /> approximately 5 to 10 feet blow ground surface (bgs) for the purpose of soil gas collection. Four <br /> of these borings will be located on the northeastern portion of the property (in the immediate <br /> vicinity of the existing bank building). The other four borings will be located on the southeastern <br /> portion of the property. The proposed soil gas collection locations are shown on Figure 2. <br /> Following sample collection, each open borehole will be grouted to the surface with neat cement. <br /> The collected gas samples will be analyzed immediately by an on-site State-certified mobile <br /> laboratory provided by TEG. <br /> Laboratory Analysis—Soil Gas <br /> Soil gas samples collected from the northeastern borings will be analyzed for total petroleum <br /> hydrocarbons as gasoline (TPHg), benzene, toluene, ethylbenzene, xylenes (BTEX), and methyl <br /> tertiary-butyl ether (MTBE) by EPA Methods modified 8015 and 8020, respectively. Samples <br /> collected from the southeastern borings will be analyzed for halogenated volatile and aromatic <br /> W:\16962\REP0RTS\W0RK_PLN.D0C 3 <br />