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r . ` 20 December 2000 AGE-NC Project No. 95-0100 Page 3 of 8 3.1. PERMITTING AND PRE-FIELD WORK ACTIVITIES Applicable site assessment permits will be obtained from the PHS-EHD. As required by PHS-EHD permitting, a health and safety plan will be prepared in accordance with Occupational Safety and Health Guidance Manual_for Hazardous Waste Site Activities (National Institute for Occupational Safety and Health Administration, U.S. Coast Guard and U.S. Environmental Protection Agency, 1985). Prior to mobilization, each soil pilot boring location will be clearly marked and a public utility clearance obtained through Underground Service Alert. 3.2. MONITORING WELL INSTALLATION AND SAMPLING As a result of ground water monitoring of the current well network, an MTBE impact to ground water has been detected in wells MW-1 and MW-3. Therefore, four additional shallow ground water monitoring wells and three deeper depth-discrete monitoring wells will be installed at the site. Proposed locations for monitoring wells are presented in Figure 2. The soil pilot borings will be advanced in the apparent down gradient and cross gradient directions from the known MTBE impact and the deeper soil pilot borings will be installed in the areas of MW- 1, MW-3 and northwest MW-3. The proposed monitoring wells will provide repeatable sampling points to monitor the MTBE impact to ground water and allow determination of site-specific ground water flow direction.The procedures for monitoring well installation and collection of soil and ground water samples are presented in Section 4.1. and Section 4.5., respectively. All borings to be completed at shallow wells (water table) are proposed to be advanced to approximately 60 feet bsg. While the borings to be completed as depth discrete, deep, monitoring wells are proposed to be advanced to approximately 85 feet bsg. Monitoring well installation activities are described below. 3.2.1. Soil Sample Collection and Analysis Due to the limits of the soil contamination in the area of the former dispenser area, soil samples will be collected at five-foot intervals from 35 feet bsg to the total depth of the borings. Field procedures for the collection of soil samples in presented in Section 4.1. At least three soil sample from each monitoring well boring will be submitted for laboratory analysis.