Large Release Event

{
  "id": "MLC-T-ENV-015405",
  "term": "Large Release Event",
  "field": "Environment",
  "definition": "Planned or unplanned uncontrolled release to the atmosphere of gas, liquids, or mixture thereof, from wells and/or other equipment that result in emissions for which there are no methodologies in § 98.233 other than under § 98.233(y) to appropriately estimate these emissions. Other large release events include, but are not limited to, well blowouts, well releases, pressure relief valve releases from process equipment other than hydrocarbon liquids storage tanks, storage tank cleaning and other maintenance activities, and releases that occur as a result of an accident, equipment rupture, fire, or explosion. Other large release events also include failure of equipment or equipment components such that a single equipment leak or release has emissions that exceed the emissions calculated for that source using applicable methods in § 98.233(a) through (h), (j) through (s), (w), (x), (dd), or (ee) by the threshold in § 98.233(y)(1)(ii). Other large release events do not include blowdowns for which emissions are calculated according to the provisions in § 98.233(i).",
  "references": [
    "40 CFR 98.238 (CFR 2024)"
  ],
  "url": "https://mlchart.com/terminology/environment/large-release-event/"
}