As part of a program to deal with the problems of waste disposal in Washington, the Department of Ecology (WDOE), in cooperation with the U.S. Geological Survey, completed a study designed to provide the geologic, hydrologic, and cultural data needed to evaluate the suitability of State land areas for the disposal of wastes. Data portraying the distribution of factors that could affect the suitability of areas in Washington for waste disposal were presented in a series of 18 maps (overlays). The factors selected include major geologic units; natural hazards from earthquakes, faulting, and volcanoes; climate; locations of major surface-water and groundwater bodies; population density; and land and water uses. Within each factor (map) the data were grouped into class intervals and the intervals for most factors ranked according to their relative suitability/unsuitability for land disposal of wastes following criteria supplied by WDOE. Areas of the State considered completely unsuitable (as determined by WDOE personnel) for waste disposal because of current or proposed land uses were excluded from ranking. (USGS)