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OWN File No. 20-1008-48 KLEINFELDER January 3 , 1992 SITE CONDITIONS During the time of our field explorations, October 30 through December 5, 1991, the Harney Lane primary landfill site ceased receiving refuse material. On this 112-acre landfill site there is located a primary and secondary landfill site and a second area to the southern end of the site from which borrow material for capping procedures is to be removed. At the time of our exploration, the landfill appeared to have received approximately two feet of cap material at the locations explored. The general surface of the landfill is either bare land or grassy and weed- covered areas. The landfill was constructed at 2 : 1 (horizontal to vertical) side slopes with crest heights of approximately 26 feet above the existing grade. The top of the landfill slopes gently upward toward the center. East Bay Metropolitan Utilities District owns an easement through the project between the southern end of the primary landfill and the northern end of the borrow area. Pacific Gas and Electric owns an easement through the project from the northern end to the southern end which delineates the primary site from the secondary site. FIELD EXPLORATIONS Field explorations for this project were performed between October 30 and December 5, 1991, and consisted of drilling and sampling six test borings to depths of approximately 25 to 40 feet below the existing crest height of the landfill . The borings were drilled with truck-mounted drilling equipment using 6-inch diameter, continuous-flight augers. Continuous logs of the soils encountered in each boring were maintained by representatives of our firm. Relatively undisturbed samples of the soil were obtained from the borings of various samples for visual observation, classification and laboratory testing. The soil samples were obtained by driving 2-inch inside diameter samplers into the soil using a 140 pound hammer falling approximately 30 inches or by pushing or driving 3-inch inside diameter Shelby tubes into the soil using the hydraulic feed on the drilling equipment or a 140 pound hammer falling approximately 30 inches. The number of blows required to advance the 2-inch samples of the soil is noted on the Log of Borings, Plates A-3 through A-8 of the appendix, at the corresponding sample locations. SOIL CONDITIONS The near-surface soils encountered at the locations explored consisted of approximately 4 feet of medium dense to loose grey- brown silty sand underlain by approximately 30 feet of refuse material. The refuse material is composed of a wide variety of construction debris, household garbage, etc. Sampling of refuse was very difficult due to wood, metal, plastic and other debris. Our boring locations were at the crest of the slopes of the Copyright 1992 KLeinfetder, Inc. Page 2 of 9