USEFUL LINKS

USGS National Geologic Map Database
USGS National Map Viewer (many available basemaps and layers, including hillshade, slope map)
FEMA National Flood Hazard Layer Viewer
USGS Groundwater Watch (deprecated, but provides information about where else to find water level data)
NRCS Web Soil Survey (valid for only the uppermost 5 to 6 feet below the ground surface)
USGS Real-Time Earthquake Map
USGS Unified (seismic) Hazard Tool 
Google Earth Pro