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Data collected during the aquifer test will be evaluated using various graphical and numerical methods, depending on flow (steady or unsteady state) well construction (fully or partially penetrating) and aquifer type (confined, leaky, unconfined, or sena-confined) The aquifer test will be evaluated using more than one method Analysis of the aquifer test data will be conducted utilizing computer software A majority of the aquifer test will be conducted using partially penetrating wells in unconfined aquifers under steady state conditions In general, the curve-fining method presented by Neuman (1975) or by Boulton (1954) will be used to evaluate transmissivity, storativity and vertical hydraulic conductivity under these conditions (the Boulton method assumes nonsteady state conditions) The Stretitsova's curve-fitting method presented by Kniseman and de Ridder (1990) may also be used for unconfined conditions In addition, the steady state well equation may be applied (Todd, 1980) to evaluate the hydraulic conductivity (away from the pumping well) If it is determined that the test was performed under confined aquifer conditions and enough time has elapsed for steady-state conditions to have been met(as defined in the literature), the Jacob distance-draw down and time-draw down methods (Cooper & Jacob, 1946) will generally be applied to evaluate storativity and ' transmissivity Alternatively, the Theis curve-fitting method (Theis, 1935) may be employed if steady-state conditions were not reached In leaky aquifers, the Hantush method(Hantush, 1956)will generally be used The capture zone will also be determined using the transmissivity values obtained through the evaluation and following the method initially outlined by Janvandei and Tsang (1986) The data will then be used to determine the construction and design specifications of the proposed system, based on the requirements of the system conceptual design(migration control, dewatering,plume capture) It must be recognized that even using theoretical models for the data evaluation, some judgment will be necessary in conducting the analyses and applying the calculated parameters to the system design Different types of aquifers may have similar draw down or response behaviors, and this must be accounted for A complete explanation of the method used and the reasoning behind the choice of method and an analysis of the results will be presented with the data evaluation The pump test will be performed in general accordance with ATC's Standard Operating Procedure — Constant Discharge Aquifer Test, which is included in Appendix A 5.11 Data Evaluation and Corrective Action Plan Following installation of the groundwater monitor wells and completion of the vapor extraction, air sparge and groundwater extraction pilot studies, ATC will evaluate the information and provide a written CAP to the SJC The CAP will conform to the guidelines established in the most recent version of the SJC Guidelines 6.0 ASSUMPTIONS • ATC will not be responsible for any unforeseen conditions (i e , shallow groundwater conditions, hard soils, unknown utilities) i EZ 100966SAFSWP ATC Associates Inc S 1EZ Sme\EZ 1009661Reports1100966SAFSWP ATC Project No 43 25 82 7 0026 13