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Task 4 - IRM Evaluation Report and Ground Water Pumping Test Workplan Wright will prepare a report and workplan that describes the following: (1) The conceptual site model and evaluation of IRMs performed in Tasks 1 and 2; and, (2) A workplan for performing and evaluating the ground water pumping test. The work plan will describe test objectives such as establishing the aquifer parameters needed for evaluating ground water extraction feasibility. We will describe the design of the test to be used, e.g. a 24-hour pumping test, number of observation wells, location of observation wells, well construction details, test and sampling protocol, proposed data analysis method, and treatment/disposition of produced ground water. Wright will submit a draft copy of the report to PHS EHD for review prior to submission of a finalized copy to PHS EHD. Tasks 2, 3 and 4 noted above respectively will be used to develop remediation plans for site cleanup. Preliminary discussions between Ramage and PHS EMD indicate that options were open for site cleanup that could include groundwater pumping or ozone injection. At this time, the remediation approach has not been finalized until the additional plume definition is completed. Technical Approach (Task 1) Four monitoring wells will be placed under approved PHS EHD permits at the locations shown on Figure 1. These wells will be placed in either public right-of-ways or private land where access agreements can be arranged. The technical approach is to perform the additional site assessment, install monitoring wells, and collect data to assist in developing interim and long-term cleanup plans for the site. CPT logs and sampling showed that contaminants were present at the 60-foot, 115-foot depths, but not at the 130-foot depth. On the basis of the CPT data, aquifer zones below 50-feet appear located at about 60 feet and 115 and 130 feet. Contaminants were present in the 60 foot and 115 foot depth but not at the 130-foot depth. Thin silt and clay strata may act as aquitards between the 50-foot and 60-65 foot depths, however the CPT logs show some vertical leakage might occur on the basis of individual stratum thickness. The deeper aquifer zone at 115 feet is separated by a sequence of silt and clay strata. These wells will require placing discrete screened intervals in the aquifer zone of interest. We propose to screen five-foot screen lengths in the wells at the 58-63-foot depth and at the 114-119- foot depth based upon our review of the cross sections prepared by Ramage Environmental and from the CPT log data. The drilling and well installation process will need to limit the potential for cross contamination and possible communication in boreholes drilled for the wells. Page 3 of 3