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Caribou Industries Proposed Alternative Seismic Improvements - 888 North Main Street July 25, 2018 Page 5 Building Code and ASCE/SEI 41-13. For the DSHA, a composite deterministic RS was compiled from the maximum of the 84th percentile spectral ordinates computed for known nearby faults. In addition to known fault sources, background seismicity was also included in the PSHA. In accordance with Section 2.4.2.1 of ASCE/SEI 41- 13, for sites located within 3 miles [5 kilometers (km)] of an active fault that controls the hazard of the site- specific response spectra, the ground motion calculations shall consider the effect of fault-normal and fault- parallel motions. The site is not near fault by this definition; therefore, fault-normal and fault-parallel motions were not considered. To convert to maximum direction ground motions, the multiplication factors recommended in Shahi and Baker (2014) were used. The site-specific probabilistic and deterministic RS were developed using the average ground motions obtained from the Next Generation Attenuation (NGA) West 2 relationships of Abrahamson et al. (2014), Boore et al. (2014), Campbell and Bozorgnia (2014), and Chiou and Youngs (2014). For all four NGA relationships, we have used an average shear wave velocity in the upper 30 meters (Vs,30) equal to 250 meters per second (m/s) based on the results of our shear wave velocity measurements near the site at the NOVA Children's Academy (Amec Foster Wheeler, 2016) and correlations of shear wave velocity using the SPT blow counts adjacent to the site presented in the Leighton repor-t (Leighton Consulting, 2006). The SPT blow counts were correlated to shear wave velocity using the method presented in the PEER Report No. 2010/03 (Brandenberg et al., 2010). Three of the borings in the Leighton report extended below 30 meters (m) (100 feet) and were used to estimate the Vs,30; the three borings were designated 8-5, HS-1, and HS-2. The results of the correlation gave Vs,30 values of 211, 270, and 273 m/s, respectively. We took the average of those results - 251 m/s - and compared it with the Vs,30 used at the NOVA Children's Academy (Amec Foster Wheeler, 2016), which was 248 m/s. We decided that a rounded value of 250 m/s is representative of the Vs,30 at the site because it lies between the two values being compared. Therefore, we used an average Vs,30 equal to 250 m/s in the analyses. We have used a depth to a shear wave velocity of 1,000 m/s beneath the site (Zi.o) of 400 m. We have used a depth to a shear wave velocity of 2,500 m/S (45) of approximately 4.55 km. These values were obtained from Cybershake (Crouse et al., 2018) which uses the latest Southern California Earthquake Center (SCEC) Community Velocity Model. The site-specific response spectrum for the BSE-l E Seismic Hazard Level was taken as the smaller of the following: 1. The mean probabilistic site-specific spectrum with a 20% probability of being exceeded in 50 years adjusted for maximum direction; or 2. The site-specific spectrum for the BSE-lN Seismic Hazard Level adjusted for maximum direction. The BSE-lN ground motion is determined from the BSE-2N ground motion. In accordance with ASCE/SEI 41-13 Section 2.4.2.1.4, the site-specific response acceleration parameters for the BSE-2N Seismic Hazard Level shall be determined based on the provisions for a Maximum Considered Earthquake (MCER) provided in Chapter 21 of ASCE 7-10. The BSE-2N response spectrum is obtained by computing both a probabilistic and a deterministic response spectrum. The site-specific BSE-lN response spectrum was computed by multiplying the ordinates of the site-specific BSE-2N response spectrum by two-thirds in accordance with Section 2.4.2.1.4 of ASCE/SEI 41-13. Additionally, a mean probabilistic site-specific spectrum with a 50% probability of being exceeded in 50 years (50-in-50) was calculated and adjusted for maximum direction. ...