20230420 19084500 1.0 TRUE TRUE NCDOT_HazardousSpillBasinBoundary NCDOT is required to include Hazardous Spill Basins on projects based upon the guidelines. The basic requirements for the Basins are the following: Applicable Locations Basins will be provided at stream crossings on highways functionally classified as a rural or urban arterials and, 1. The stream (1) is identified as an Outstanding Resource Water (ORW) or a WS-I watersupply, or 2. The stream (1) crossing is within 1/2 mile of the critical area (2) of a water supply source classified as WS-II, WS-III and WS-IV. (1) For the purpose of these guidelines "stream" will be defined as those depicted as blue lines on 7-1/2 minute (1:24000 scale) United States Geological Survey (USGS) quadrangles. (2) Critical area is defined as extending 1/2 mile from the normal pool elevation of a reservoir; or 1/2 mile upstream of , and draining to an intake. This would make the effective area for hazardous spill basins placement, within 1.0 mile of the normal pool or upstream of an intake. To Develop a HSB coverages that identifies the potential need for an HSB, the following data sources are identified as needed: HYAR (24K Hydrography Line - Classified) HYARUT (24K Hydrography Line - Unnamed Trib) HYPL (24K Hydrography PolyLine - Classified) HYPLUT (24K Hydrography PolyLine - Unnamed) HQORWDWQ (Includes ORW and WS_I and WS_II WSW) WSW (Water Supply Watersheds) SWI (Surface Water Intakes) This data set contains all HSB Boundaries Latest Publication Date: 03/15/2026 : 17:45 NC North Carolina NCDOT ESM Last Publication Date: 03/15/2026 : 17:56 NCDOT GIS Unit iVBORw0KGgoAAAANSUhEUgAAASwAAADICAYAAABS39xVAAAAAXNSR0IB2cksfwAAAAlwSFlzAAAO xAAADsQBlSsOGwAAAqpJREFUeJzt1DENADAMwLAd5U+5o7BvimQjyJXZ3T0AAfM7AOCVYQEZhgVk GBaQYVhAhmEBGYYFZBgWkGFYQIZhARmGBWQYFpBhWECGYQEZhgVkGBaQYVhAhmEBGYYFZBgWkGFY QIZhARmGBWQYFpBhWECGYQEZhgVkGBaQYVhAhmEBGYYFZBgWkGFYQIZhARmGBWQYFpBhWECGYQEZ hgVkGBaQYVhAhmEBGYYFZBgWkGFYQIZhARmGBWQYFpBhWECGYQEZhgVkGBaQYVhAhmEBGYYFZBgW kGFYQIZhARmGBWQYFpBhWECGYQEZhgVkGBaQYVhAhmEBGYYFZBgWkGFYQIZhARmGBWQYFpBhWECG YQEZhgVkGBaQYVhAhmEBGYYFZBgWkGFYQIZhARmGBWQYFpBhWECGYQEZhgVkGBaQYVhAhmEBGYYF ZBgWkGFYQIZhARmGBWQYFpBhWECGYQEZhgVkGBaQYVhAhmEBGYYFZBgWkGFYQIZhARmGBWQYFpBh WECGYQEZhgVkGBaQYVhAhmEBGYYFZBgWkGFYQIZhARmGBWQYFpBhWECGYQEZhgVkGBaQYVhAhmEB GYYFZBgWkGFYQIZhARmGBWQYFpBhWECGYQEZhgVkGBaQYVhAhmEBGYYFZBgWkGFYQIZhARmGBWQY FpBhWECGYQEZhgVkGBaQYVhAhmEBGYYFZBgWkGFYQIZhARmGBWQYFpBhWECGYQEZhgVkGBaQYVhA hmEBGYYFZBgWkGFYQIZhARmGBWQYFpBhWECGYQEZhgVkGBaQYVhAhmEBGYYFZBgWkGFYQIZhARmG BWQYFpBhWECGYQEZhgVkGBaQYVhAhmEBGYYFZBgWkGFYQIZhARmGBWQYFpBhWECGYQEZhgVkGBaQ YVhAhmEBGYYFnIoLreIHHblfYqUAAAAASUVORK5CYII=