3.1 Assessment and Classification

3.1.1 Spill of National Significance

A Spill of National Significance (SONS) is a spill that, due to

  • severity,
  • size,
  • location,
  • actual or potential impact on the public health and welfare or the environment, or
  • the necessary response effort is so complex that it requires extraordinary coordination of Federal, State, local, Tribal, and responsible party resources to contain and clean up the discharge.

A discharge may be classified as a SONS by the Administrator of US EPA for discharges occurring in the inland zone and the Commandant of the USCG for discharges occurring in the coastal zone. For a SONS in the inland zone, the US EPA Administrator may name a senior Agency official to assist the OSC in communicating with the affected parties and the public and coordinating Federal, State, local, Tribal, and international resources at the national level. This strategic coordination will involve, as appropriate, the NRT, RRT(s), the Governor(s) of affected State(s), and the mayor(s) or other chief executive(s) of local government(s).

3.1.2 Worst Case Discharge

CWA Section 311(d)(2)(J) requires the ACP to include procedures and standards for removing a worst case discharge of oil and for mitigating or preventing a substantial threat of such a discharge. A "worst case" discharge for the purposes of this plan will be the catastrophic release as identified in Facility Response Plans (FRPs) submitted to US EPA. Since this is a requirement of OPA, only oil scenarios will be listed. See Appendix III: Worst Case Discharges in Region 5 for information on individual sites.