An Administrative Order and Reporting Requirement is being issued to Tate & Lyle located in Houlton, Maine. Tate & Lyle processes starch made from tapioca into a variety of modified starches to customer specifications. The processing of the starch begins by mixing propylene oxide with the starch. The batch process includes mixing the starch and propylene oxide for 65 to 70 hours. The propylene oxide is stored in a 20,000 gallon above ground storage tank without any air pollution controls. Emissions from the tank occur during expansion of stored propylene oxide and during the filling of the tank. Tate & Lyle failed to design the propylene oxide storage tank in compliance the National Standards for Volatile Organic Liquid Storage Vessels found at 40 CFR Part 60 Subpart Kb (Storage NSPS). Tate & Lyle is order to comply with the Storage NSPS by installing a control device or redesigning the propylene oxide storage tank system.