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GEOTECHNICAL ENVIRONMENTAL WATER RESOURCES CONSTRUCTION SERVICES COASTAL/MARINE GEOTECHNICS 2010 Crow Canyon Place, Suite 250  San Ramon, CA 94583  (925) 866-9000  info@engeo.com www.engeo.com Project No. 5150.100.001 November 11, 2024 Mr. Dan Yoon Hana Japan Steak House 7298 San Ramon Road Dublin, CA 94568 Subject: Hana Japan Steak House 11991 Dublin Canyon Road Pleasanton, California RESPONSE TO COMMENTS Dear Mr. Yoon: We are pleased to provide the following response to comments for the Hana Japan Steak House project in Pleasanton, California. For our use, we were provided with Reference 4, by BSK Associates (BSK), dated September 6, 2024. For completeness of the record, we restate BSK’s comments in italics, followed by our responses. Our intent is to provide this response to comments, and upon concurrence by BSK, update References 1, 2, and 3 as appropriate, to document the modifications. Comment 1 CBC Update Letter: The letter characterizes the Site as Site Class D whereas the Geotechnical Report characterizes the Site as Site Class C. Some of the values provided in Table 1 appear to be consistent with a Site Class C, while others are consistent with Site Class D. The discrepancy between Site Class characterizations and their associated seismic design values should be clarified. In addition, consideration should be given to providing an appropriate justification for the Site Class selected. ENGEO Response to Comment 1 Our use of Fa of 1.2 and Fv of 1.7 site coefficient values, which correlate to parameters for Site Classes D and C, respectively, was intentional. The 2008 recommendations were based on the 2007 California Building Code (CBC), which was based on the 2005 version of ASCE 7 “Minimum Design Loads for Buildings and Other Structures” (ASCE 7-05). The current parameters are provided in accordance with the 2022 CBC, which is based on the 2016 version of ASCE 7 (ASCE 7-16). A difference between the two versions of ASCE 7 is the encouragement to use Site Class D with a Fa value not less than 1.2 for sites where “the soil properties are not known in sufficient detail to determine the site class,” (Sections 11.4.3 and 11.4.4). Since we did not measure a shear wave velocity and we did not explore to a depth of 100 feet in the exploration that supports Reference 2, we judge that applying a Site Class D but with a Fa value of 1.2 to be in alignment with the 2022 CBC. Note, on online seismic design parameter websites, this combination is referred to as “D Default.” We will update Reference 3 to better reflect this information.