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drilled to a depth of about 30 feet. Seven borings will be drilled to depths of 50 to 60 feet: four borings on the KRC property and three borings at the Mokelumne River crossing. Borings may be deepened if, in the judgment of the project geologist/engineer, suitable foundation has not been encountered. Borings at the Mokelumne River crossing will penetrate about 25 feet into Mehrten Formation. Borings on the KRC property will be used to provide a materials assessment beneath the proposed pipeline. A bentonite-based drill fluid will be circulated through the boring to remove drill cuttings and to stabilize the hole. A boring log will be compiled by the field geologist/engineer as the boring is advanced. Pitcher Drilling Co. of East Palo Alto will perform the work under contract to CH2M Hill. 5. Sampling. Standard Penetration Tests (SPT) will be performed at 5-foot intervals and at material changes at the discretion of OCC's field geologist/engineer. Cohesive soils will be tested with a pocket penetrometer to assess their shear strength. Sampling for corrosion testing will be coordinated with CH2M Hill staff to obtain appropriate samples at required locations and depths. A California Modified sampler may be used if a larger sample or unit weight determination is required is required. Pitcher barrel sampling is not planned but could be requested under certain circumstances, e.g. to obtain undisturbed samples in weakly cemented or indurated soils. OCC will deliver soil samples to Cooper Testing Labs of Mountain View for geotechnical testing. Corrosion samples will be retained by CH2M Hill for delivery to a laboratory of their choice. 6. Geotechnical Testing. We will select one or two soil samples per boring for grain size distribution tests. Atterberg limits tests will be performed on selected fine-grained soil samples. The grain size distribution will be used to evaluate soils for potential use as pipe bedding or other backfill. 7. Piezometers. Eight borings will be completed as piezometers to monitor water levels: 2-10; 2-11; 2-16; 2-18; 2-23; and 2-25. Boring locations are described in Table 1. Piezometers will consist of a short length(2 to 5 feet) of slotted, 1-inch-diameter, schedule 40 PVC pipe wrapped with filter fabric. The slotted section will be placed in the zone selected for monitoring by the field geologist. Blank pipe will be placed to the surface. Sand will be placed in the annulus from 1-foot below to 1-foot above the slotted section of pipe. Bentonite pellets will be placed in the bottom of the hole if the bottom of the pipe is more than 1-foot above the bottom of the hole. One-foot of G1PROJECTS\EBMUD\1113\1113.2PSJC_PRM2.DOC 2 Olivia Chen Consultants, Inc.