[en] Envelope C waste includes Hanford Tank 241-AN-102, which contains high levels of organic complexants and high levels of soluble aluminum. Supporting SRTC studies of processes require the use of a simulant for AN-102 Supernate. A simulant has been developed that contains the levels of soluble transition metals observed in tank AN-102. Development of the simulant was based on the most recent characterizations of AN-102 waste. Estimating the amount of gluconate ion present in the AN-102 supernate was necessary to produce the correct soluble metals concentrations. The simulant formulation is based on the nominal composition of Tank AN-102 supernate at 9.5 molar sodium and diluted to 6.5 molar sodium concentrations