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0 r2/RRRM <br /> 2.0 PROPOSED SCOPE OF WORK GEOMA7lg1X <br />' The proposed scope of work includes advancing four borings using Geoprobe (or an equivalent <br /> direct-push method) and collecting soil and groundwater samples for analysis of PHCs A <br />' monitoring well will be installed at one of the locations, based on information gained from the <br /> four borings The scope of work is based on discussions with PHS/EHD and CVRWQCB staff <br /> Iand is designed to provide data with which to further assess the lateral and vertical extent of <br /> PHC contamination resulting from a release from the former USTs <br />' 2.1 FIELD INVESTIGATION <br /> Prior to initiating any field work, an application for "Permit to Construct Monitoring Wells <br />' and/or Soil Borings for the Purpose of Subsurface Investigation," will be submitted to <br /> PHS/EHD for their approval Additionally, all potential drilling sites will be marked in the <br />' field and Underground Services Alert, the Port's Maintenance Department, and the tenant will <br /> be contacted to clear the sates for drilling prior to proceeding <br />' The field investigation will be carried out in general accordance with the "Tri-Regional Board <br /> Staff Recommendations for Preliminary Investigation and Evaluation of Underground Storage <br /> Tanks" (North Coast Regional Water Quality Control Board, et al, 1990) Soil borings will be <br /> advanced, sampled, and backfilled according to procedures given in Boyajian & Ross (1998), <br /> rAppendix B Soil samples will be collected for PHC analysis according to procedures given in <br /> Boyajian & Ross (1998), Appendix C and groundwater samples will be collected for PHC <br /> analysis according to procedures given in Boyajian & Ross (1998), Appendix D The <br /> monitoring well will be installed, developed, and sampled in general accordance with ASTM <br /> Standard D5092-90, "Design and Installation of Groundwater Monitoring Wells in Aquifers," <br /> and ASTM Standard D 4448-85a, "Sampling Groundwater Monitoring Wells " <br /> 2.1.1 Exploratory Borings <br /> Four exploration sates have been selected based on the recorded directions of groundwater flow <br /> and considering the location of nearby industrial facilities (Figure 2) The borings at each of <br /> these sates will be advanced to approximately 40 feet bgs using direct push technology <br /> (Geoprobe or equivalent) Soil samples will be collected at 5-foot intervals starting at 10 feet <br /> bgs (the approximate depth of the water table) and ending at 30 feet bgs (the lowest extent of <br /> soil contamination in the vicinity of the tanks) The samples will be screened using a <br /> photoionization detector (PID) and samples will be selected in consultation with PHS/EHD for <br /> laboratory analysis of PHCs (TPH-g and BTEX) At least one sample from each boring (most <br /> 11PROJBC1k6437 00616437 Wk Pln Site 3 doe 5 <br />