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HAZUS. A Level Two Risk Assessment is a more refined evaluation using local data such as soil maps, assessor's records, local building code history and so on to more accurately reflect local conditions than when using only national data. Level Two Assessments are generally more accurate than Level One Assessments, but still rely on generalized, typical data, rather than building specific data. A Level Three Risk Assessment is building- or facility-specific, using detailed data for each facility. A Level Three Risk Assessment cannot be done for an entire community, but rather is typically done for a single building or a few buildings or other facilities that may be particularly vulnerable or for which mitigation of seismic hazards is a high priority. 10.5.1 Level Two Risk Assessment The Level One earthquake loss estimates presented above are based on census-tract level data. For a given community, such as the Eugene/Springfield Metro Area, a more accurate loss estimate could be obtained by incorporating Level Two local data into the loss calculations. Such data could include: 1) better inventory data, 2) spatial distribution of inventory within census tracts, 3) overlay of soils information with inventory to identify areas subject to amplification, liquefaction, settling and displacements, and 4) refinement of building fragility curves to reflect local inventory. Such Level Two loss estimates would be more accurate than the Level One assessments presented above. However, the Level One estimates probably provide accurate enough estimates of the approximate magnitude of losses for emergency planning purposes. Furthermore, conducting a Level Two loss estimate would require very intensive data collection and processing efforts, without providing enough detail for specific mitigation projects. Therefore, Level Two risk assessments may not be as useful for the Eugene/Springfield Metro Area as the Level Three Assessments suggested below. 10.5,2 Level Three Risk Assessment The potential damages and losses from earthquakes affecting Lane County and the Eugene/Springfield Metro Area are very high. However, the probability of such earthquakes is relatively Iow and many types of buildings, such as wood frame homes, are generally expected to perform reasonably well in earthquakes. Therefore, widespread mitigation of seismic hazards is probably not called for in the case of most ordinary or typical buildings. That is, seismic mitigation actions are probably necessary only for a small percentage of the total building stock in the Eugene/Springfield Metro Area. Furthermore, buildings constructed since the early 1990s generally meet current seismic design requirements and will generally perform fairly well in future 10-14