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Program levels and the difference in worst-case release analysis requirements

The preamble to the Risk Management Program Rule (61 FR 31668; June 20, 1996) states that "one worst-case release scenario will be defined to represent all toxics, and one worst-case release scenario will be defined to represent all flammables held above the threshold at the source" (61 FR 31671). The preamble language further specifies that owners and operators of stationary sources need only "report one worst-case release scenario for all flammables and one worst-case release scenario for all toxics at the source" (61 FR 31683). These general discussions do not address any differences among Program 1, 2, and 3 requirements. Are the worst-case release analysis requirements for Program 1 processes different than those for Program 2 and 3 processes? Must a worst-case release scenario analysis be completed and reported for each Program 1 process?

Yes. The regulations at 40 CFR §68.25(a)(1) state that one worst-case release scenario must be analyzed and reported in the risk management plan for each Program 1 process. In order for any process to be eligible for Program 1 requirements, it must be demonstrated that a worst-case release from that process would not affect any public receptor (40 CFR §68.10(b)(2)). For Program 2 and 3 processes, a single worst-case release scenario analysis may be reported to represent all regulated toxic substances, and a single worst-case release scenario analysis will be acceptable to represent all regulated flammable substances. Additional worst-case release scenarios must, however, be analyzed and reported for Program 2 and 3 processes if worst-case releases from other covered processes potentially affect public receptors different from those affected by the first worst-case release scenario (40 CFR §68.25(a)(2)).