Southwest Shipyard, L.P. - Executive Summary
The affected chemicals under 68.130, Table 1 are Acrylonitrile and Vinyl Acetate Monomer. These chemicals are stored in tanks with secondary containment and the tanks are equipped with relief valves in case of rupture. To prevent overflow, the tank volume is noted daily and the volume to be added is carefully estimated and if the volume is more than 70%, the contents are then added in small increments. During transfer operations to tanker trucks, the transfer is carefully monitored during the entire duration by atleast one facility person and if there is a spill, the transfer is discontinued immediately by the closing the valves which are installed on the tanker trucks and in the individual tanks. |
The substances under Table 3, 68.130 are Butadiene, Butane, Butene, Propane and Propylene. These are normally contained in the tank barges which dock at the shipyard for degassing. The storage of the flammables are temporary but often the flammables can stay in the tank barges for 1 or
2 days. The tank barges are always under pressure. The degassing is conducted by routing the gases through a flare. During the depressurization procedure, the substances are sent from the tank barges to the flare for incineration. There are alarms and relief valves on the tank barges if there is a leak or if there any other hazards. There are also valves on the tank barges to shut down the flow of the flammables to the flare if there is leak. The transfer operation (from tank barge to flare) is carefully monitored by atleast one facility person.