Accurately determine the distance of a given building site relative to known active fault near-source zones in California and the Nevada border using these new active source fault maps, developed specifically for use with the 1997 Uniform Building Code (UBC). This map book contains more than 200 detailed maps in an 11-inch by 17-inch format, at a scale of 1:150,000 and is an essential reference tool for building officials, civil and structural engineers, geotechnical engineers, architects, and anyone in the design/construction industry working on projects in Zone 4 in California and adjacent Nevada, which are subject to the 1997 Uniform Building Code seismic provisions.