Data is provided from an evaluation of the accuracy of the nuclear gages in comparison with the currently used non- nuclear methods of determining soil density and moisture content. The research study was principally theoretical in nature and was conducted in two parts with each part respectively considering density and moisture content. Two existing commercial gages were evaluated, and a nominal experimental program employing non-soil standards of known density and composition was conducted to verify the density results. The results of the moisture content study were checked against data in the literature.