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KLEINFELDER SCOPE OF WORK The following scope of work was developed to assess the vertical limits of crude oil impacted soil and potential impact to groundwater beneath the rupture area. As part of assessing the vertical limits of the petroleum impacted soil, the sampling and analyses will be performed to pre-characterize the soil prior to future disposal. The following sampling and analyses plan for pre-characterization for disposal purposes assumes an estimated volume of approximately 20,000 cubic yards of affected soil. Kleinfelder understands that assuming 20,000 cubic yards of affected material, local landfills will require one 4-point composite sample for every 2,000 cubic yards of soil. Pre-characterization of the material is based on in-situ sampling and disposal to a Class 11 Landfill. Please note however, that should pre-characterization indicate disposal of material to a Class I Landfill, then the soil should not be directly loaded for disposal during future excavation activities. Under these conditions Kleinfelder recommends stockpiling and additional soil sampling and analyses to reduce potential disposal costs. SOIL SAMPLING A total of 104 discrete soil samples will be collected from twenty nine (29) push probes advanced within and near the estimated footprint area of petroleum impacted soil (Plate 1). Four of these pushprobes will be advanced to assess groundwater conditions (GI through G4). Gl will be located within the footprint area and G2, G3 and G4 will be located near the perimeter of the surveyed footprint area. Twenty five locations (P1 to P25) will be placed within the footprint area. Nineteen of the 25 probes advanced in the footprint area will be located within a grid-like pattern generally based on a 75-foot spaced grid pattern. Six of the remaining 25 probes will be advanced in the assumed greatest petroleum impacted areas located east and northeast of the rupture site (Based on aerial photograph depicting surface oil accumulation and field observations by Kleinfelder). The twenty five pushprobes (P1 to P25) will be advanced to depths ranging from the surface to approximately 20 feet below ground surface (bgs) [maximum estimated depth of petroleum impacted soil] within the surveyed footprint of the spill area. Kleinfelder anticipates that up to half of the pushprobe borings located in less impacted areas, will not have to be advanced to depths greater than ten feet bgs. The four pushprobe borings Gl through G4 will be advanced to approximate total depths of 40 feet bgs. The actual total depths of the pushprobes will be based on field observations and field screening using a photo-ionization detector (PID). The PID measures ionizable compounds in air in parts per million by volume (ppmv). Therefore, based on field screening and observations, greater sampling depths may be necessary. Kleinfelder proposes to collect approximately 88 discrete soil samples from the proposed 26 pushprobe locations advanced in the footprint area (P1 through P25 and Gl). These discrete samples will be collected in petroleum impacted soil based on field observations and PID readings for profile purposes. Kleinfelder estimates that two discrete soil samples will be collected for laboratory analyses from eight probe locations (P5, P12, P13, P14, P22, P23, P24 and P25) in the southwest portion of the footprint area and four discrete soil samples collected from the remaining pushprobe 02001PROP.ENV/ST04P118/DH:ss Page 1 of Copyright 2004,Kleinfelder,Inc. March 22,2004