Tragedy, Compounded
Previously on the explosions in West, Texas, I explored how anhydrous ammonia could still present a hazard to the community and asked questions about how aware the community was of the risk. In the subsequent days, however, it becomes clear that this explosion highlights some far, far more glaring omissions in government regulation of hazardous materials and their storage facilities - omissions that directly contributed to the size and scope of this tragedy.
As of this writing, the number of bodies found has climbed to 14, with over 200 people injured. It is unclear if any still remain missing. Residents on the edge of the impacted area have just now been allowed back to their home, but many more remain displaced.
Most distressing, however, is this:
The fertilizer plant that exploded Wednesday had at least 540,000 pounds of potentially dangerous ammonium nitrate in a storage building, a 2012 company filing with the state health department shows.
Ammonium nitrate (NH4NO3) is, as previously discussed, the nitrogen fertilizer much better known for its involvement in explosive incidents. The Oklahoma City bombing, for example, involved a mixture of 4800 pounds of ammonium nitrate, nitromethane, and diesel fuel. The Texas City disaster involved a cargo ship carrying approximately 2300 tons of ammonium nitrate. If we assume the amount stored at the West Fertilizer Co. was the amount stated in their filing with the state health department, it comes out to 270 tons - slightly more than a tenth of what was involved in the Texas City disaster. It is by no means certain that this was the cause of the blast - it is still possible that anhydrous ammonia played a role - but it certainly changes the equation.
Ammonium nitrate is known to be a strong oxidizer. As such, it presents a significant fire hazard when combined with other combustible materials. However, pure ammonium nitrate can be difficult to ignite and even when ignited, for the reaction to turn explosive requires some level of confinement. Its decomposition into gases typically occurs at temperature well above 200 degrees Celsius, but this temperature can be lowered by the presence of impurities. Because the decomposition reaction is highly exothermic - produces a great deal of heat - it can start a runaway chain reaction, where each decomposition starts another. It remains, at this point, unclear what mechanism directly caused the explosion; to some extent, that discussion is academic.
Because of the role ammonium nitrate has played in terrorist acts and the ease with which explosives can be produced from it, the Department of Homeland Security requires notification when a fertilizer plant or depot holds more than 400 pounds of it on site.
Yet a person familiar with DHS operations said the company that owns the plant, West Fertilizer, did not tell the agency about the potentially explosive fertilizer as it is required to do, leaving one of the principal regulators of ammonium nitrate - which can also be used in bomb making - unaware of any danger there.
It is worth noting that anhydrous ammonia - of which the plant was also permitted to hold on site - is also subject to DHS reporting. Indeed, anhydrous ammonia is also reported to the EPA under its Risk Management Program, where companies submit plans on storage and handling of certain hazardous chemicals - which does not include ammonium nitrate. It is from these documents that the company reported a worst case scenario of a ammonia fuel leak.
Looking at the Tier Two form filed by West Fertilizer for 2012, the first where they reported the presence of ammonium nitrate on site, it becomes clear that something is off. The number of days they report having this quantity of ammonium nitrate on site is 365 - implying its presence before January 1st. The reactivity box is not checked (and while I do not know what the state standards are for that box, I would certainly mark a strong oxider which needs to be stored separately from reducers, powdered metals, and strong acids as reactive). Perhaps the only small comfort is that the existence of the Tier Two report means that they may have sent this information to the local fire department, as required by the state.
Reports continue to indicate that the safety features required for storage of the chemicals which they had on-hand were not present:
The plant’s plan said there was no risk of fire or explosion and noted they had no sprinklers, water deluge or other safety mechanisms installed.
“We do not yet know what happened at this facility. The ongoing investigation will inform us on the plan’s adequacy,” Gray said.
The Texas Commission on Environmental Quality also dealt with the company and issued a permit for handling anhydrous ammonia, which requires safety equipment the company had told the EPA it didn’t have. But TCEQ acknowledged it may never have checked to confirm the equipment was there.
“It’s a minor source under the Clean Air Act so it doesn’t get much scrutiny at all,” said Neil Carman, a Sierra Club clean air expert and chemist who used to work for the TCEQ.
Inspections, of course, are piecemeal. OSHA reportedly had not inspected the facility since 1985, while some Texas inspectors may have been there as recently as the beginning of April, checking for compliance in labeling. The Texas Commision on Environmental Quality last sent inspectors to the plant in 2006. Despite this, the company still managed to rack up a couple of fines over the past several years:
Last summer, the U.S. Pipeline and Hazardous Materials Safety Administration fined West Fertilizer $10,000 for safety violations, including planning to transport anhydrous ammonia without adequate security and failing to properly label ammonia tanks. The company paid a reduced fine of $5,250 after agreeing to take corrective action. The fine was reported by several news organizations.
In 2006, the company was fined $2,300 by the EPA for not having filed a risk management plan, according to the EPA’s compliance database. The EPA said it had poor employee training records, failed to document hazards and didn’t have a written maintenance program. The EPA said the company corrected the deficiencies and filed an updated plan in 2011 – making no mention of the presence of ammonium nitrate – and was then in compliance with EPA regulations.
It remains unclear if this level of fines would be considered typical for a facility of its size, but certainly it does not invoke warm and fuzzy feelings when combined with the other evidence. Although the plant was offset from the town when it was built in 1962, the growth of the community around it - and the presence of a school across the railroad tracks - would hopefully have encouraged a culture of safety and decision making based on more than just profit. The evidence suggests otherwise, and it is unfortunate that it wasn’t discovered before this tragedy - just after.