AESI collaborated with the National Park Service to conduct geotechnical analysis for improvements to the Mammoth Hot Springs Hotel. The improvements to the hotel consisted of structural and seismic stabilization of the Lobby, Porte Cochre, and Map Room areas of the historic hotel, as well as upgrades to life and safety, mechanical and electrical systems, and ADA and egress to meet current codes. AESI’s work consisted of several components. Subsurface explorations were conducted with sample collection from the borings and blow counts of the materials to determine their in-place density and stiffness. Groundwater levels were measured, coordinating with the park geologist to obtain temperature and gas measurements of the bore holes during the drilling. Select samples were then analyzed in the laboratory to verify soil classification, natural moisture content, atterberg limits, and gradations. Based on the field and laboratory data, the site’s overall geotechnical conditions were analyzed with the final deliverable for the project being a geotechnical report complete with the results of a previous seismic study conducted in the area by AESI for the Law and Justice Center.