Respondent is a refrigerated warehousing and storage business which experienced a release of anhydrous ammonia on March 29, 2017 that resulted in a response from the local Fire and Rescue department. Following this event, the facility was requested to provide answers to a Chemical Release Questionnaire (CRQ) by EPA, pursuant to CERCLA ยง 104(e). Respondent’s answers to the questionnaire stated that the March 29, 2017 release was 1,865 pounds of anhydrous ammonia. During the March 29, 2017 release, traffic on nearby streets was shut down. The Facility’s alarm and ventilation system failed to operate in the “machine room” where the ammonia system was located, although the machine room’s sprinkler system had improperly activated. The Facility’s refrigeration process and ventilation system were only manually operated from inside the machine room (where the release occurred), and Respondent and the Fire Department were unable to shut down the system or ventilate the machine room. “Level A” personal protective equipment was ultimately required to make entry to activate ventilation. The release continued for at least four hours. The cause of the ammonia release was found to be a failed pressure relief valve. Respondent’s CRQ response stated that 1,265 pounds of anhydrous ammonia were released to the air, and 600 pounds drained to the sewer system. On or about October 3, 2017, the EPA conducted an inspection of the Facility to determine Respondent’s compliance with Section 112(r) of the CAA (the EPA inspection). Information gathered from Respondent’s answers to the CRQ and during the EPA inspection revealed that the Respondent processed, handled, and/or stored the anhydrous ammonia at the Facility. From the time Respondent first stored and used onsite anhydrous ammonia at the Facility, Respondent was subject to the requirements of Section 112(r)(1) of the CAA because it was the owner and operator of a stationary source that was producing, processing, handling or storing a regulated substance listed pursuant to Section 112(r)(3).