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2.0 SCOPE OF WORK ' Compliant with the DTSC's request and consistent with their verbal communication to ASPI, Montgomery Watson will conduct a soil vapor survey at the Site. Soil gas samples will be ecollected from the vicinity of the former Norge and Deluxe facilities and from soils along sewer laterals on the west end of the parcel. Montgomery Watson will also collect soil vapor samples on the ASPI property near the adjacent Service Laundry and Dry Cleaning. Methodology utilized for the soil vapor survey will be consistent with the "Requirements for Active Soil Gas Investigation (October 1995),"prepared by the State of California RWQCB,Los Angeles Region and as further described below. Montgomery Watson anticipates a one-day field investigation but is prepared to expand the scope depending on field conditions encountered. 2.1 GEOPHYSICAL SURVEY Montgomery Watson will subcontract Subtronics Corporation, a company that specializes in identifying and locating sanitary sewers and other utilities. These services are necessary for three reasons: 1. The building which housed the Norge and Deluxe facilities has been demolished. It is not known whether the sanitary sewer laterals were capped or abandoned. Montgomery Watson is not confident that reliable points of reference remain which would allow placement of soil vapor sampling points to accurately represent the path of the former sanitary sewer. 2. Montgomery Watson prefers to collect soil vapor samples below points of release. Lacking construction details for the sanitary sewer, Montgomery Watson would prefer to use a geophysical survey to identify not only the path of the sanitary sewer but also the depth at which it is buried so that the soil vapor samples can be collected from soils lying beneath the sewer line and possible points of release. 3. Clearing the utilities at any site is a safe work practice. Exposure to hazardous materials is not very likely during this survey, but the active collection of soil gas samples requires that sampling probes be driven into the soil, in this instance beneath an asphalt cover. A utility clearance will minimize the possibility of accidental encounter with active utilities and will also minimize the possibility of interrupting essential services at the site. ' If either a manhole or sewer clean out is available for access, Subtronics Corporation employs a radio transmitter and receiver to identify and locate the sanitary sewer line. Having located the sewer line, Subtronics then uses a video device to positively identify laterals extending from the main line. Subtronics will use an electromagnetic device to identify the other utilities and clear ' anticipated soil vapor sampling locations. The sewer will be identified on the ground by marking 4