The site is unaltered except for agricultural uses and the baseline radiological condition can be readily measured. The mining to the northeast in the west central Florida phosphate area has been extensively studied and can serve as a point of reference for the proposed site. The document describes the background condition of the natural radiation environment in the absence of the proposed mining facilities. The only radionuclides having potential for significant impact are those of the uranium-238 decay series. The relative importance of the thorium-232 series are addressed. The discussion centers upon the natural and disturbed condition of uranium-238 series radionuclides. Specific items to be covered include uranium associated with the phosphate, the uranium series including radium-226 and radon-222, radon progeny, terrestrial gamma radiation, airborne radioactivity, subsurface profiles of radioactivity, radium-226 in surface waters, and radium-226 in groundwaters.