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Site Characterisation Report: 7500 West Eleventh Street, Tracy, CR. Page 8 •'"% baseline and offset techniques requires a minimum of two persons — one to control each end of the tape — SJC is concerned that such direction of the engineering work by unlicensed USTCF staff, appears to amount to the unlicensed practice of professional t1 engineering, which is prohibited by the Professional Engineers and Surveyors Act. This concern is magnified by the USTCF staff's refusing to fund site characterization work to the east of Chrisman Road, which, as will be discussed later, prevented reliable definition of the lateral extent of the plume of groundwater affected by the release of hydrocarbons to the subsurface at the subject site. In an attempt to comply with the funding and technical limitations imposed by the USTCF staff, SJC used tapes to produce a map of the 15.5-acre area of concern that is t: shown on Figure 2. It should be carefully noted, however, that the accuracy of that map should not be considered to comply with normal professional engineering standards. The 4 SJC survey party included a civil engineer supported by one, and for a portion of the time, two field technicians. In addition to the limitations of the surveying methods employed, windy conditions on the site, which were typical of those that often prevail in the Tracy area, considerably reduced the efficiency with which the tape survey could be performed, as did the need to run tapes across West Eleventh Street, a busy four-lane highway that could not be closed, and thus posed safety concerns for the surveying crew. .j SJC used an engineer's level to determine the surface elevations at exploratory borings and groundwater-quality monitoring well locations. To ensure the accuracy of those elevations and to provide the ability to relate them to regional topographic and hydrogeologic features, the elevations were calculated by running a leveling traverse from San Joaquin County Benchmark No. AA394, located on the west side of Chrisman Road, some 1,000 ft. south of its intersection with West Eleventh Street That Benchmark's elevation is 52.584 ft. MSL. i So that borings could be safely drilled in the area, United Service Alert (USA) was notified; that agency arranged for the locations of underground utilities to be marked prior to the commencement of on-site work. Additional underground utility location work ' was performed by SJC because past experience working at the 7500 West Eleventh Street site had shown that the USA records were not entirely accurate or complete. z 3.3 Permitting Prior to the commencement of exploratory drilling and groundwater-quality monitoring i well construction at the site, the necessary drilling permits were obtained from the SJCPHS. Encroachment permits for installation of groundwater-quality monitoring wells along West Eleventh Street were obtained from the San Joaquin County Department of 4 I Public Works (SJCDPW). Bonds for the maintenance and eventual removal of those wells were also obtained to as to comply with the requirements of that agency. Note: Ms. Lori Duncan was present on the site to represent the SJCPHS at various times during the implementation of the site characterization program, including periods when subsurface borings were drilled, groundwater-quality monitoring wells were installed, SJC