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OBJECTIVE AND SCOPE OF SITE ASSESSMENT As mentioned previously, the purpose of the proposed work is to implement a feasibility study and to complete the groundwater investigation at the site. The work proposed herein is the first phase what is anticipated to be three phases of work. The first phase includes installing three vapor wells, two monitoring wells, and an air sparge well. The second phase will include conducting soil and groundwater pilot testing. Upon obtaining results of the pilot tests, Smith Technology will prepare a Corrective Action Plan (CAP), the third phase of work. The following is a description of methodology to install the proposed three vapor wells, two monitoring wells, and an air sparge well; and collecting soil and groundwater samples at the project site. PROPOSED SCOPE OF WORK Installation of Vapor Extraction Wells, Monitoring Wells and a Sparge Well Smith Technology will advance a total of six soil borings and complete the borings as three vapor wells, two monitoring wells, and one air sparge well. All drilling will be conducted by a State - licensed (C57) drilling company using hollow stem augers. Proposed well locations are shown on Figure 2. A field geologist will be present to log all drill cuttings and soil samples. Descriptions of soil types encountered, sample collection intervals, and well construction details will be recorded on boring/well logs. Soil samples will be collected at a minimum of five foot intervals or at changes in lithology and up to two samples from each boring will be sent using chain -of -custody record to a State -certified laboratory for analysis of total petroleum hydrocarbons as gasoline (TPHg) and benzene, toluene, ethylbenzene, and xylenes (BTEX) by EPA method 8015/8020. Vapor Wells Three borings will be advanced to depths of approximately 15 feet below ground surface (bgs) and completed as 2 -inch diameter vapor wells. It is anticipated that a 0.01 -inch slotted screen will be placed from 6 to 15 feet bgs. Proposed vapor extraction well construction details are shown on Figure 5. Monitoring Wells Based on evaluation of Supply Well data, in addition to the close proximity of the contaminant plume from the Supply Well (30 feet) monitoring wells will be placed within five feet of each other ("clustered") to investigate the vertical transport of contaminants and evaluate hydrogeologic conditions at the site. A 8 5/8 -inch conductor casing will be employed in the construction of the deeper monitoring well to prevent the deterioration of water -bearing formations which may be penetrated. The Supply Well boring log indicates sandy soils exist to a W:\94326\REPORTS\WRKPLN.DOC 3 ��