In nuclear power plant siting, redetermination of hypocenters of instrumentally recorded earthquakes in the site region may be better than relying on routinely determined hypocenter locations listed in standard earthquake catalogues. Routinely determined hypocenters, particularly those of small earthquakes or of earthquakes occurring before the mid-1950s, may be so mislocated that they present a misleading picture of the seismo-tectonics of the site region. The preferred method for redetermining a hypocenter depends on the earthquake being considered. The hypocenters of many pre-1954 earthquakes may be more accurately redetermined by now-standard computerized location techniques that were not available when the earthquakes...