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1 KLE/NFELOER enynrv<ooie.xymmwno,. Task 1 — Pre-Field Activities The pushprobe subcontractor and/or Kleinfelder will contact Underground Service Alert (USA) 48 hours prior to conducting fieldwork to notify various utilities of our proposed subsurface assessment. Kleinfelder will additionally prepare a health and safety plan prior to the actual field assessment. Task 2 — Advancement of Pushprobes The purpose of the pushprobe assessment is to define the extent of sulfuric acid impacted soils associated with the former AST operations. The total proposed depths of the pushprobes are 25 feet bgs, but the depth/s will be based partly on field observations and use of pH test strips of potentially impacted soil. Therefore, some borings may be deeper or shallower than 25 feet. Kleinfelder is proposing a single day of work and the advancement of approximately eight pushprobes, approximately four within the former containment area, three peripheral probes and one background probe. An attempt will be made to advance the background probe in soil similar to that noted in the assessment area and outside of facility operations. The actual pushprobe locations will be dependent on access, surface conditions, and potential interference with subsurface and above-ground utilities. Groundwater depths are unknown at this time. Based on Kleinfelder's experience, relatively-shallow perched water conditions may exist, although subsurface water is not expected to be encountered or sampled as part of this scope of work. The shallowest groundwater aquifer is expected to be beyond the proposed total probe depth of 25 feet bgs. Groundwater flow direction in the site area is unknown to Kleinfelder. Prior to the advancement of the perimeter pushprobes, the first 4 feet will be hand- augered to assess potential underground utilities. Pushprobes will be advanced using a pneumatically driven steel probe. Soil samples will be obtained by inserting a sample barrel lined with acetate liners into the probe. The sample barrel will be lowered to the desired sampling interval and driven into the soil. The sample liners will be removed, and the selected sampling interval will be sealed with Teflon sheets and plastic end Soil samples will be collected continuously during the advancement of the pushprobes at depths ranging from near surface to the proposed maximum depth of approximately 25 feet bgs. During the advancement of the borings, soil samples will be collected for lithologic classification based on the Unified Soil Classification System (USCS). Three soil samples are proposed to be collected at each probe location at varying intervals based on field observations. A relatively shallow soil sample will be collected 97064.T1/STO8P785 August 29,2008 ©2008 Kleinfelder Page 2 of 5