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P I, The ground water has a contamination plume that extends horizontally from the station to the east. Well MW-11 is the most easterly well at this site. The vertical depth of the plume is from the water table to an unknown depth but boring B-4 found contamination at 160 feet bgs. In the past we had a Vapor Extractor System operating starting in July 1997 to October 2003. The system removed about 46,411 pounds of gasoline vapor from this site. On July 27 and 28 , 2005 we installed two monitoring wells (MW-14 and MW-16) to test the contamination . IV Contaminate Transport The Hydraulic Conductivity of the groundwater is 0. 07203 Feet/Day or 0. 00060 Feet/ Minute . The shallow ground water flows to the northeast. This shallow groundwater is retained from descending by clay layer located at 38 to 42 feet bgs on the west side to the station . The majority of the contamination originates near a line from MW-6 to MW-4. It flows to the east from that point. The highest point of contamination is in well MW-1 . To treat this contamination , we will have to treat the water along that line and near the highest source area around MW-1 . V Remedial Action Objectives and Processes The contamination plume could be treated with processes to destroy the contamination as it passes through the area. This can be performed by using a C-Sparger system or by treating the groundwater with a PulseOX 100 system or natural attenuation . Process 1 The C-Sparger wells will be placed in the area near the edge of the site plume. Our plan would be to place a C-Sparger System in the area close to the east edge of the plume at this site. The work plan will show the position of the wells and their depth . This will be accomplished by placing six (6) sparging wells in front of the plume. This work plan will control the majority to the plume. The estimated cost for this process , this includes the sparging wells, will be around $92 , 000. 00. Process 2 The treatment of the groundwater by use of a PulseOX system would obtain data to adjust the plume clean up. We discussed this with Applied Process Engineering and they recommended we do a pilot test for four month to see if the PulseOX system will operate properly. The cost to operate a recommended pilot test for this system for four months will cost approximately $26, 660. 00. We will have to install two extractor wells to a depth of 65 feet. The cost to install the wells will be about $5, 000. 00 plus 14 hours for the supervisor, which will cost about $1 ,600. 00. Four samples will cost around $2 , 000. 00. The water from the nearest monitoring well will be tested every three weeks to monitor the amount of contamination removed . Water samples taken during the PulseOX System testing will be six samples and the cost will be around $ 1 ,620.00. 5