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GE GENESIS ENGINEERING&REDEVELOPMENT these materials,the soil beneath will be sampled as appropriate. If the soils have been impacted by COPC,then additional sampling may be performed to delineate the extent of impacts. Any additional impacted soil that is identified will be excavated and disposed of as described in the sections below. S.3 Excavation Excavation will be performed in each of the thirteen AOC to remove soil (or ash from AOC 13) impacted by the COPC as detailed in Section 3.1 and shown on Figure 3. Prior to excavation,each of the borings will be located based on their GPS coordinates reported in Arcadis(2102). After boring re-location,the perimeter of each AOC will be marked based on the dimensions shown on Figure 3. Before removing the impacted soil,vegetation in the areas to be excavated will be cut off at the ground surface, segregated, and removed from the work area. Removal of vegetation is to be performed using hand-held mechanical equipment to minimize disturbance of soil prior to excavation. The soil excavation methods will include mechanical excavation using rubber-tired or track- mounted backhoe, excavator, and loader. Soil will be excavated and stockpiled on and covered with plastic sheeting on the eastern part of the Site. During excavation, stockpiling, and loading, soil will be moistened as necessary to reduce dust generation using water trucks or hoses. Additional details for minimizing fugitive dust are included in the Dust Mitigation Plan (Appendix F). 5.4 Confirmation Sampling After excavation of impacted soil,confirmation soil samples will be collected from the base and perimeter of the excavations to confirm that concentrations of COPC in soil are below respective RAO. Soil sampling procedures are detailed in the SAP(Appendix B). For each AOC, confirmation samples will be analyzed for only those COPC that exceeded their RAO as reported in Arcadis (2012). Confirmation sampling will use the Incremental Sampling Methodology(ITRC 2012). Each AOC will be divided into 5 decision units ("DU"),with each of the 4 sidewalls and the base of the excavation as its own DU. For each DU, at least 30 incremental samples will be combined to form a single sample for each DU in each AOC. All subsequent sample processing will be performed by the laboratory. If the confirmation sample analysis indicates target cleanup levels have been attained, no further excavation will be conducted. If the analytical results of confirmation sampling indicate target cleanup levels have not been attained for a particular DU,then further Former Gordon Research Company Property 15 of 20 Removal Action Workplan June 2017