Seismic design requirements for critical facilities normally require the development and application of a uniform hazard spectrum having a specified return period. For a soil site, hazard results are often evaluated for bedrock level and soil surface. In many instances, use of soil hazard results can be problematic for a generic site response result because un-conservacive generic soil amplification functions may have been used in the ground morion attenuation model or a site specific result may be required.