Hines Energy Complex - Executive Summary |
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This risk management plan (RMP) is for Florida Power Corporation's Hines Energy Complex. The Hines facility is an electric generating plant that contains two combined-cycle natural gas/oil-fired combustion turbines. The process affected by Section 112(r) requirements is storage of aqueous ammonia, which is used for selective catalytic reduction of NOx emissions. The ammonia concentration in water is 30%, and it is stored in a 250,000 pound tank. The tank is surrounded by a dike that is 55 feet by 22 feet by 4 feet high. The maximum amount of aqueous ammonia stored on-site in 1998 was 249,600 pounds. Since the ammonia concentration is less than 40%, this process is not subject to OSHA PSM standards. The major hazard associated with the storage of aqueous ammonia is the unlikely event of a storage tank failure. Using EPA's OCA guidance, a tank failure was modeled. Under this worst-case scenario, the contents of the storage tank leave the tank into the diked area surrounding it. The diked area is 55 feet by 22 feet, or 1,210 square feet in area. Using the given density factor of 0.55, the maximum area of the ammonia pool created by the spill is 0.55 X 249,600 = 137,280. Since the diked area is smaller, the guidance requires that this dimension be used in further calculations (1,210 sq. ft.). The release rate, QR, is 1.4 X LFA X A, where LFA is the liquid factor at ambient temperature (0.026), and A is the area diked (1,210 sq. ft.). Therefore, QA = 1.4 X 0.026 X 1,210 = 44 lbs./min. Using OCA guidance reference Table 10, the distance to the toxic endpoint is 0.1 mile. There are no public or environmental receptors located within this distance from the ammonia storage tank. Releases are prevented through the use of well-maintained storage equipment. There have been no releases of aqueous ammonia at the site during the last five years. In fact, the facility is new; it was installed in September 1998. Ammonia storage quantities have been reported to, a nd emergency response procedures coordinated with, the District 7 LEPC, which is the Polk County Emergency Operations office. |