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Minutes - San Leandro City Council Meeting - June 10, 1991 Page - 4 - NEW BUSINESS (continued) of sites to determine appropriate setbacks from fault zones. He said the subsurface investigation was performed on the westerly fault zone, and was not necessary on the easterly zone because the fault is well exposed. He said the proposed setbacks for this site are 40' to 60' laterally, which is a conservative distance. He said it is quite common in other projects to find setbacks of only 20' . Pete Kaldveer described the relationship of cut and fill grading to seismic activity. He said no major landslides would be anticipated for this site. He said the fill used on site will be high quality and will neither attenuate nor amplify an earthquake on the site. The City Council asked questions regarding the reaction of crushed rock fill on bedrock; whether the fill would liquefy; how fill compares to bedrock; what would happen if a foundation were constructed partially on bedrock and partially on fill ; and the overall gradient of project. Loring Wyllie, Chairman of the Board of H.J. Degenkelb, San Francisco, described his firm, clients, his background, and other projects. He said he has been a consultant on a number of projects in which homes were constructed close to earthquake faults. He said the houses proposed for this site can be safely built. He said amplification of an earthquake would be much greater closer to the San Leandro Marina Area than to this site because the ground at the Marina is less firm. He said wood frame structures are the safest type of structure in an earthquake. He described types of construction that can cause problems in an earthquake. He discussed what can be done to ensure safety of a structure in an earthquake. He said each structure should be individually engineered with chimneys reinforced and well tied to structures, veneers well anchored, etc. He also recommended that the design of the structures be peer-reviewed by either the City or an independent engineer, and that some form of special structural inspections be conducted during construction. The City Council asked questions regarding the location of the two roadways in project, the type of footings to be used, and the design of garages. Roy Parker, Transportation Coordinator, said there are two traffic concerns associated with the proposed project: 1) geometrics of the entrance off Lake Chabot Road and 2) traffic generated by project. He described traffic control requirements and said they are the same as those currently utilized for entrance to Astor Drive. He discussed traffic generation during peak periods, and said the project does not cause any intersection to change to an unsatisfactory level of service. Pat McCllelan, Disaster Preparedness Coordinator, described the geology of the Bay 0 Vista Area, which he said is the same rock unit as in Chabot Terrace. He described earthquake shaking as it moves away from a fault line. He described the City's damage assessment response priorities in response to a disaster and the City's plan to establish and train neighborhood response teams and to install Disaster Arks in neighborhoods, and the requirement for an ark in this neighborhood if the project is approved. He said any damage to roadways in this project would probably not require extraordinary effort to repair.