Memphis tank truck disaster

The accident occurred at the interchange in Midtown Memphis between I-40 and the western terminus of I-240. Approaching this interchange from the west, I-40 travels in an east–west alignment and shifts into a north-south alignment at this interchange. I-240 also meets the interchange from a north-south alignment.[1] When the interchange was first constructed in the 1960s, it was planned as a four-way interchange; I-40 was to continue straight through the interchange in an east-west alignment, and I-240 was to continue north of the interchange on what is now I-40.[2] Many residents opposed the routing east of this interchange because it was slated to pass through Overton Park, and filed a series of lawsuits to stop the interstate's construction. These lawsuits culminated in the 1971 U.S. Supreme Court case Citizens to Preserve Overton Park v. Volpe,[3] and in 1981, the Tennessee Department of Transportation (TDOT) abandoned plans to route I-40 east of this interchange.[4] Instead, the department chose to redesignate the northern loop of I-240 north of this interchange as part of I-40. As a result of these original plans, however, the interchange was constructed as a four-way cloverstack interchange, and contained several unused ramps and bridges intended to carry traffic to and from I-40 east of the interchange.[2] I-40 traffic continuing both through the interchange and exiting onto I-240 was required to use one-lane ramps, some of which contained hazardously sharp curves.[5] The ramp where the accident occurred was a flyover ramp with an advisory speed limit of 25 miles per hour (40 km/h).[6] At the time of the accident, the entire interchange was considered one of the most dangerous in the state and had a crash rate much higher than the state average.[7] TDOT had begun preliminary work in early 1988 for a project to reconstruct the interchage, estimated to cost $100 million at the time (equivalent to $190 million in 2019[8]).[6]

On December 23, 1988, at approximately 10:15 a.m. Central Time, a 10,450-US-gallon (39,600 l) tanker truck hauling 9,511 US gallons (36,000 l) of pressurized liquid propane skidded off of a ramp carrying traffic on I-40 eastbound at the Midtown interchange in Memphis, rolled about 1 1/4 times, and crashed into a retaining wall.[9][10] The subsequent crash ruptured the tank, which produced a vapor cloud and caused a boiling liquid expanding vapor explosion (BLEVE) seconds later, which produced a fireball estimated to be about 700 feet (210 m) wide and 700 to 800 feet (210 to 240 m) tall.[11] This set nearby vehicles on fire and killed five motorists, including the driver of the truck.[12][13] The force of the explosion then propelled the tank from the highway, causing it to strike a nearby overpass bridge before exiting the freeway right-of-way, bouncing off of the ground, and crashing into a duplex about 125 yards (114 m) away from the crash site. This instantly killed an occupant of the complex and started a fire which subsequently spread to multiple other buildings and cars.[14] Most of the tractor was propelled into the southbound lanes of I-40.[9] Other parts of the truck, including tires and an axle, were hurled from the crash site into nearby homes. The crash created a traffic jam that extended several miles in all directions, and about one hour after the crash, a truck on I-240 northbound crashed into stopped vehicles at the south end of the traffic congestion, killing the driver.[15] In addition to the truck, a total of seven other cars were completely destroyed by the explosion.[9] Ten other cars, seven houses, and one industrial building were damaged by the explosion and subsequent fires.[14][9] A total of 10 people were injured, and two people who were inside of homes impacted by the crash died the following day from their injuries.[16] Several of the injured were treated for severe burns, and some of the deceased victims were burned beyond recognition.[17]

Diagram of the crash. Note that I-40 is referred to as I-240 on the right side.

Investigators from the National Transportation Safety Board arrived on the scene the following day. They determined that the truck had passed an inspection in Arkansas the day before the accident, and that the driver was familiar with the route.[18] The driver, an employee of Wooten Transports, had picked up the load in nearby West Memphis, Arkansas, and was en route to Ellendale, about 20 miles (32 km) northeast of Memphis.[10]

Authorities identified the deceased motorists as Randall Benson (29, driver of the tanker truck) of West Memphis, Arkansas, Harrison G. Lee (34) of Brighton, Tennessee, Robert Wardlow (40) of Memphis, Tina Wiles (30) and Warner Wiles (70), both of Vicksburg, Mississippi, and David Bailey (29, driver of second truck) of West Helena, Arkansas. Shelanda Towles (10), Iva J. Rubesheim (87), and James M. Malone (57) were identified as the deceased occupants of the homes which were impacted by the blast.[18]

The National Fire Protection Agency (NFPA) investigated the accident and released its report on February 6, 1990. The report determined that the exact cause of both the explosion and the leakage that caused the explosion were unknown, but theorized the ignition might have started in a house that the vapor cloud had expanded into.[9]

Between June 2003 and December 2006, TDOT spent $53 million to completely reconstruct the interchange where the accident occurred.[19] The unused ramps and bridges were demolished, and the interchange was converted into a directional T interchange.[20] In addition, the interchange with SR 14 (Jackson Avenue) on I-40 directly north of the interchange was modified, and multiple auxiliary lanes and slip ramps were constructed to improve traffic flow and reduce crashes caused by sudden lane changes. Before the project could begin, TDOT had to acquire additional right-of-way, which was opposed by some residents of the area. This subsequently delayed the start of the project by several years.[19]

• Waverly, Tennessee tank car explosion