The pipeline safety statute directed the Office of Pipeline Safety (OPS) to describe areas that are unusually sensitive to environmental damage in the event of a hazardous liquid pipeline release, and to establish a method for identifying hazardous liquid pipelines located in those areas. The goal is to provide added protection to these particularly sensitive areas.

Once USAs are identified and located, pipeline operators will conduct risk assessments to determine if a release from a particular pipeline segment can impact an USA. The risk assessments will include consultations, when necessary, with Federal and state agencies responsible for protecting threatened and endangered species, depleted marine mammals, or critical drinking water resources. Segments of pipeline where a release could impact an USA will be subject to additional prevention, mitigation, and response measures.