[en] A laboratory test was developed to determine the relative aggressiveness of nuclear process waste on mild steel. Tensile samples were strained to fracture in synthetic waste solutions in an electrochemical cell with the sample as the anode. When total elongation in the test is less than the uniform elongation observed in air, stress, corrosion cracking is likely if the steel is exposed to equivalent solutions and temperatures in service. A response surface equation was derived that relates elongation of a mild steel (ASTM A 285-B) to the combined effect of four independent variables of the waste solution: temperature, NO₃/sup -/, NO₂^-, and OH^-. Elongation in the electrochemical tensile test, as a measure of stress corrosion cracking potential, can be predicted from the actual waste compositions to within an average of 8 percent of the measured values. The electrochemical tensile tests showed that the supernates in SRP salt receiver tanks are the least aggressive compositions, and wastes newly generated by the separations process are the most aggressive ones. Test data also verified that ASTM A 516-70 steel is superior to ASTM A 285-B. To decrease the possibility of stress corrosion cracking, limits were recommended for waste compositions, based on present results wedge-opening-loaded test results, and expected plant operating conditions. 12 fig