EPA conducted an inspection of the Facility on May 15-17, 2018, to determine Respondent compliance with Section 112(r) of the CAA and 40 CFR Part 68. Respondent failed to maintain documentation for the worst-case scenario to illustrate the rationale and accuracy of the scenario. It was unclear as to which vessel containing vinyl acetate was the worst-case, as required by 40 CFR 68.39(a). Respondent failure to implement its written procedures to maintain the ongoing integrity of process equipment pursuant to 40 CFR 68.73(b), failure to perform inspections and tests on process equipment, and at a frequency consistent with applicable good engineering practices pursuant to 40 CFR 68.73(d)(2)-(3), is a violation of 40 CFR 68.12(d)(3),