Sec.  21.116   Topographical data.

   

   Determining the location and height above sea level of the antenna
   site, the elevation or contour intervals shall be taken from United
   States Geological Survey Topographic Quadrangle Maps, United States
   Army Corps of Engineers maps or Tennessee Valley Authority maps,
   whichever is the latest, for all areas for which such maps are
   available. If such maps are not published for the area in question,
   the next best topographic information should be used. Topographic data
   may sometimes be obtained from State and municipal agencies. Data from
   Sectional Aeronautical Charts (including bench marks) or railroad
   depot elevations and highway elevations from road maps may be used
   where no better information is available. In cases where limited
   topographic data is available, use may be made of an altimeter in a
   car driven along roads extending generally radially from the
   transmitter site. If it appears necessary, additional data may be
   requested. United States Geological Survey Topographic Quadrangle Maps
   may be obtained from the Department of the Interior, Geological
   Survey, Washington, DC 20242. Sectional Aeronautical Charts are
   available from the Department of Commerce, Coast and Geodetic Survey,
   Washington, DC 20230.

   [ 44 FR 60534 , Oct. 19, 1979, as amended at  52 FR 37783 , Oct. 9, 1987]