Section 304 covers all releases of listed hazardous or extremely hazardous substances, including those involved in transportation in excess of the reportable quantity (RQ). Owners or operators of transportation facilities may call 911 or the local telephone operator, in order to satisfy Section 304 notification requirements when a release occurs during transportation. Local emergency planning committees should work with the local 911 system and telephone operators to ensure such transportation release notifications are immediately relayed to the community emergency coordinator.