Two new approaches were used to separate ammonia from various fractions of organ nitrogen compounds in oil shale wastewaters, thereby permitting the application of a rapid, but unselective, method for total-N determination to the direct estimation of organic N. In contrast to the Kjeldahl digestion method, neither separation method uses intense heat. The first method uses reverse phase chromatography to separate polar from no polar nitrogenous compounds; no polar solutes are retained by a C18 bonded silica cartridge and eluted with methanol and tetrahydofuran. The second uses monosmotic dissolved gas dialysis to separate volatile from nonvolatile nitrogenous solutes; nonvolatile compounds are retained in a tubular, micro porous polytetrafluorethene membrane after dialysis against an acid solution. These two methods were applied to 12 oil shale retort waters, and the resulting measures of organic N were correlated against organic Kjeldahl nitrogen values. Correlation coefficients for the nonpolar and nonvolatile nitrogen values were 0.996, respectively. Relative standard deviations averaged 3.9%.