Gilman Brothers Company (GBC) manufactures polystyrene foam boards at its Gilman Road, Gilman, CT facility (Facility). The blowing agent used in the manufacturing process is isobutane. As isobutane is one of the listed chemicals in 40 CFR 68 and the amount of isobutane handled at the Facility exceeds the 40 CFR 68 threshold, GBC is required to prepare and submit to the United States Environmental Protection Agency (USEPA) a Risk Management Plan (RMP) conforming to 40 CFR 68 requirements for the isobutane process. GBC retained GZA to prepare the RMP and submit it to the USEPA.


GZA reviewed the isobutane process, related specifications and drawings, process hazard analysis (PHA) report and process safety management (PSM) manual. GZA modified the PHA report and the PSM manual to improve its accuracy and developed the emergency response and prevention program information required for the RMP. Based on the above, GZA developed a hypothetical worst-case accidental release scenario and a scenario that involves a more realistic potential accidental release of isobutane from the Facility. GZA also performed the required Off-site Consequence Analysis (OCA) for these scenarios in accordance with USEPA’s guidance document using USEPA’s RMP-COMP software to assess off-site impacts from these accidental releases.


Using the above information, GZA prepared the RMP conforming to 40 CFR 68 and submitted it electronically to the USEPA using USEPA’s web-based RMP*eSubmit submission system.