National Geodetic Survey

Near-surface disposal units must be marked in such a way that the boimdaries of the units can be easily defined. Three permanent survey marker control points, referenced to USGS or National Geodetic Survey control stations, must be established on the site to facilitate surveys. 

Horizontal and vertical controls must be provided by USGS or National Geodetic Survey control stations as checked against USGS or National Geodetic Survey record files. 

U.S. Geological Survey, part of the U.S. Department of the Interior, and the National Geodetic Survey, a branch of the National Oceanic and Atmospheric Administration. 

National Oceanic and Atmospheric Administration National Geodetic Survey http //www.ngs.noaa.gov... 

The National Geodetic Survey (NGS), part of NOAA s National Ocean Service, coordinates a network of more than 400 CORS stations which receive GPS radio signals 24 hours a day, 7 days a week. The GPS data collected at these stations allow GPS users to determine more accurate positions through computation after the data are collected. 

Ekman, M. (1988). The Impact of Geodynamic Phenomena on Systems for Height and Gravity. Proceedings 2nd Research School, Nordic Geodetic Commission, Ebeltoft, Denmark. National Land Survey, Sweden. 

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