This paper presents Bureau of Mines research into the corrosion rate of industrial electrogalvanized steel in deaerated molar ammonium sulfate by DC and ac electrochemical techniques as compared to solution analysis by atomic adsorption. An evaluation of the zinc coatings obtained in an industrial-scale test has shown that coatings obtained from a waste-derived electrolyte perform better than normal industrial coating. Impedance diagrams show that a slightly different frequency distribution is obtained for the two different coatings studied. The time dependence of the zinc corrosion rate can be monitored using impedance data over a frequency range of 0.1 to 11 hz. Admittance plots provided the double-layer capacitance values, which indicate the presence or absence of surface corrosion products. The results show that electrochemical ac techniques can be applied to successfully determine the zinc corrosion rate of electrogalvanized steel in near- neutral media and that waste sources of zinc are viable for electrogalvanizing steel.