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Federal
Altitude of the top of the Upper Hell Creek hydrogeologic unit in the Williston structural basin recent views
Department of the Interior —
These data represent the altitude, in feet above North American Vertical Datum of 1988 (NAVD88), of the Upper Hell Creek hydrogeologic unit in the Williston... -
Federal
Altitude of the top of the Upper Hell Creek hydrogeologic unit in the Powder River structural basin recent views
Department of the Interior —
These data represent the altitude, in feet above North American Vertical Datum of 1988 (NAVD88), of the Upper Hell Creek hydrogeologic unit in the Powder River basin....