The research described in this report was aimed at initiating and developing processes and process modifications that could be incorporated into semiconductor manufacturing operations to accomplish pollution prevention, especially to accomplish significant reduction in the quantity of arsenic waste generated in that industry. The effort resulted in the development of processes for the recovery of both gallium and arsenic from gallium arsenide semiconductor crystal manufacturing. Recovery of materials from both solid and aqueous waste streams was achieved and the solids recovery process was demonstrated at an operating semiconductor manufacturing plant. The processes developed herein are applicable to other types of III-V semiconductor manufacturing, including indium phosphide, gallium phosphide and indium arsenide manufacturing. The two processes developed include processes for recovery of materials from both solid and aqueous waste streams.