Overview: Now that the three-step THIRA process has been completed, the Stakeholder Preparedness Review (SPR) must be completed over the next 12 months. In your role as the Emergency Manager for Gra

Overview: Now that the three-step THIRA process has been completed, the Stakeholder Preparedness Review (SPR) must be completed over the next 12 months. In your role as the Emergency Manager for Gra 1

EMH201 – Risk and Vulnerability

Assessment

Graniteville, SC,

Many trains traveled through the quiet mill town each day. A rail spur in the center of the town serviced the Avondale plant, which employed most of the town’s citizens and received daily deliveries of chlorine gas via a Norfolk Southern train for mill operations. The switch connecting the spur to the main line had to be turned manually for deliveries. Contributing to the failure, no feature or mechanism existed to remind crewmembers of the switch position and prompt them to complete the switch before departing the work site. The investigative team of the National Transportation Safety Board (NTSB) concluded that “the distance required for the [moving] train[‘s] crew to perceive the banner of the misaligned switch, react to it, and brake the train to a safe stop was greater than the distance available” (2).

The chlorine spill occurred as the result of a train crash at 2:39 a.m. on January 6, 2005, after someone forgot to toggle the switch to disconnect a spur from the main line (Figure 2). The incorrectly toggled switch mistakenly diverted Freight Train 192 from the main line onto the spur at 47 mph (76 km/h). Train 192 subsequently collided into parked Train P22, derailing three engines and 18 cars (3). Roughly 60 tons of liquefied chlorine gas spilled out of the ninth of 42 freight cars. The liquefied gas rapidly vaporized, with volumetric expansion 450:1 (4).

The engineers were unharmed in the crash; however, the deadly chlorine gas seeped through the air. The crash sound awakened local residents, and initial notification came through a 911 call within 1 min. The Aiken 911 call record indicated reports of a “bleach gas smell and smoke on the ground,” and at least one caller identified chlorine (5). Fire and rescue services responded within 1 min of notification and were enroute within one more minute; however, upon hearing a radio report of a “smell of chemicals,” the fire department chief ordered responders to stand by. Within 6 min, the fire department chief stood 1,000 ft (305 m) from the crash and was forced to withdraw lest he be overcome by chlorine fumes, which were spreading rapidly and approaching critically toxic levels. Within 13 min, the chief recognized the need for a mass evacuation and relocated upwind. Emergency responders marshaled personnel and equipment, established incident command, requested mutual aid, activated Reverse 911 with instructions to shelter in place, and initiated a major evacuation (6). However, these actions did not take place with immediacy and efficiency.

About 5,400 residents were evacuated. The chlorine gas had already affected many people: 554 were treated at hospitals, 75 were admitted, and nine would eventually die from its poison (2): the train’s engineer (who had survived the crash), three workers in the mill, a truck driver sleeping in his cab, a man in a shack one block from the wreckage, two workers who had evacuated the mill on foot into the woods, and one other person (7).