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Blowup Over Ammonium Nitrate

Senate hearing on Texas explosion reveals dangerous regulatory gaps, deep divisions between chemical safety board and EPA

by Jeff Johnson
July 15, 2013 | A version of this story appeared in Volume 91, Issue 28

Credit: Adrees Latif/Reuters/Newscom
Some 30 tons of ammonium nitrate exploded at the West Fertilizer facility in April, leaving a wide crater.
An aerial photo shows the aftermath of a massive explosion at a fertilizer facility in the town of West, near Waco, Texas April 18, 2013.
Credit: Adrees Latif/Reuters/Newscom
Some 30 tons of ammonium nitrate exploded at the West Fertilizer facility in April, leaving a wide crater.

Despite a century-long and worldwide history of tragic ammonium nitrate accidents, only a patchwork of inadequate U.S. safety regulations is in place to avoid more accidents involving this common fertilizer and deadly explosive. That is the primary conclusion of an investigation by the Chemical Safety & Hazard Investigation Board (CSB) of the West Fertilizer Co. ammonium nitrate explosion that killed at least 14 people in April and destroyed the small Texas community of West.

The plant is similar to more than 6,000 other U.S. facilities that, the board said, also lack oversight.

CSB presented its report at a volatile Senate Environment & Public Works Committee hearing on June 27. The hearing revealed severe regulatory shortcomings as well as a deep and fundamental division between the board and the Environmental Protection Agency, a split underscored by Sens. Barbara Boxer (D-Calif.) and David Vitter (R-La.), the committee chair and ranking minority party member, respectively.

Although Boxer and Vitter have tangled in the past, they were united in their anger at EPA and support of CSB.

Boxer blasted EPA for failing to follow a 2002 CSB recommendation to expand EPA’s risk management program (RMP) regulations to include reactive chemicals such as ammonium nitrate. Such action, she argued, might have avoided the accident. And Vitter charged that recent EPA attempts to use CSB-obtained accident investigation material for enforcement purposes would undermine the board’s independence and unique authority as an accident investigator. A recent EPA attempt to subpoena CSB investigators to testify before a grand jury, he said, would “put the board out of business.”

The hearing was called primarily to examine the cause and the implications of the April 17 accident at the West Fertilizer facility and briefly update the committee on the ongoing CSB investigation of a June 13 accident at a Williams Cos. olefins plant in Geismar, La., that killed two workers. It did not address Department of Homeland Security antiterrorism efforts to secure high-risk chemicals such as ammonium nitrate. Rather, nearly the entire hearing focused on West and regulatory loopholes in worker and community safety measures related to ammonium nitrate.

On May 3, 2013, U.S. Chemical Safety Board investigator Jerad Denton took a film crew into West, Texas, to document the level of community damage from the fertilizer explosion that killed 14 and injured about 200 others. This 3-minute video shows the devastation.
Credit: CSB

At West, “safety was governed by a patchwork of U.S. regulatory standards and guidance with many large holes,” testified CSB Chairman Rafael Moure-Eraso. The firm was a common agricultural retail supplier and part of the town since 1961. It’s similar to some 6,500 other small agricultural retailers that dot U.S. farm communities. At the time of the explosion, the West facility held 60 tons of ammonium nitrate, which it blended and sold to farmers. About half of that material exploded, the board found.

Ammonium nitrate is a crop nutrient and makes up about 2% of total nitrogen fertilizers applied annually in the U.S. But it is also a strong oxidizer that can react violently, particularly when coupled with organic material, Moure-Eraso noted. It can be reactive by itself, capable of runaway decomposition reactions and detonation, especially when spurred by heat, fire, shock, confinement, and contamination. The chemical has been the source of many accidents, the worst of which occurred in 1947—at the port of Texas City, Texas—when a series of explosions killed nearly 600 people.

Because of its accident potential as well as other security implications, ammonium nitrate’s agricultural use has declined by about half since 2005. According to the Department of Agriculture, about 719,000 tons of ammonium nitrate was applied in the U.S. in 2010, the last year for which data are available.

During the evening of April 17, the West retail warehouse caught fire. The ammonium nitrate was stored in wooden bins next to combustible seeds, which likely contributed to the fire’s intensity, Moure-Eraso explained. The storage facility had no sprinkler system, no fire walls, and no systems to automatically detect or control fire. Under current regulations, installation of these devices is voluntary, and “West did not volunteer,” he noted.

The fire led to a blast that flattened the surrounding area, badly damaging three schools, a nursing home, and an apartment complex, all of which had been constructed in the 50 years since the facility was built. CSB’s investigation found it was likely that emergency responders were unaware of the danger posed by ammonium nitrate or the quantities on the premises. The explosion occurred only 20 minutes after the volunteer fire department was called. Twelve firefighters and emergency responders died, as did two members of the public.

“The damage to homes, schools, and businesses was almost beyond imagination—even by standards of large-scale chemical disasters.”

A host of regulations touch on ammonium nitrate storage, but none provide protective safety oversight of the chemical when kept at retail facilities. Looking at fire codes developed by the National Fire Protection Association and the International Code Council, a building code and standards association, CSB found they did not specifically address the West situation and the safety provisions within the codes that could apply to West are “confusing or contradictory.” Texas has no statewide fire code, nor does the county where the company resides.

The Occupational Safety & Health Administration, the primary federal industrial safety body, does have ammonium nitrate regulations but through provisions addressing explosives. These provisions, however, do not prohibit explosive material from being stored in wooden structures or bins or require sprinkler systems for facilities like West. Despite many ammonium nitrate accidents over many years, CSB found that wooden buildings remain the norm for storage of the chemical. In addition, CSB also found the last OSHA inspection at the West facility was in 1985.

Moure-Eraso also discussed at the hearing the role of two rigorous regulations: OSHA’s process safety management (PSM) standard that calls for safety protection for highly hazardous chemicals and EPA’s RMP, which requires companies to specifically address the community impact of potential accidents caused by “extremely hazardous substances.” However, neither program lists ammonium nitrate as a covered chemical.

But in 2002, following an extensive study of accidents caused by highly reactive chemicals, CSB unsuccessfully urged that OSHA and EPA include reactive chemicals, such as ammonium nitrate, in their PSM and RMP standards.

Another regulatory path may have been available to warn residents of West, Moure-Eraso said: the Emergency Planning & Community Right-to-Know Act of 1986 (EPCRA). The federal law and regulations did lead West to report the presence of up to 270 tons of ammonium nitrate to the McLennan County Local Emergency Planning Committee, he said. But the law does not require the company to provide this information to the volunteer fire department or the emergency planning commission. And the company did not.

A more fundamental flaw in this law is its reliance on local emergency planning committees to take action, Moure-Eraso added. In places like West, these committees are largely staffed by volunteers or local officials with other daily responsibilities. In the end, it would be up to the volunteer fire department to figure out what was in store for them at West Fertilizer and how best to fight that fire.

Credit: Wikimedia Commons
Ammonium nitrate was the cause of the West Fertilizer explosion.
Photo shows ammonium nitrate powder on a red surface.
Credit: Wikimedia Commons
Ammonium nitrate was the cause of the West Fertilizer explosion.

After the testimony of Moure-Eraso, the senators turned to Barry N. Breen, a principal deputy assistant administrator at EPA, whose testimony was a short, general discussion of EPCRA and RMP regulations. Breen failed to mention ammonium nitrate was not covered under EPA’s RMP regulation, nor did he identify shortcomings in EPCRA.

Noticeably angry, Boxer shot back to Breen: “That is the most vague testimony I have ever heard.”

For the next 20 minutes, Boxer quizzed and criticized Breen—with the senator pointing to the impact of industrial accidents and Breen discussing regulatory provisions. Boxer blasted EPA for a “lack of urgency” in updating its regulations. Breen countered by pointing to an ammonium nitrate alert EPA issued in 1997, which led Boxer to accuse him of taking credit for an EPA alert issued “in the last century.”

But Boxer was focused on EPA’s failure to comply with the 2002 CSB recommendation that EPA expand its RMP regulations to include reactive chemicals, particularly ammonium nitrate. She pledged to work with CSB and EPA to improve the regulations and warned Breen that her staff may become involved with the agency “more than you might like.”

When Vitter got his turn to quiz the EPA official, he voiced his fear that EPA was trying to piggyback on CSB investigations and using the fruit of its accident investigations for enforcement purposes.

Vitter pointed to a Feb. 15 letter from Moure-Eraso to Robert Perciasepe, acting EPA administrator. In this letter, which is not publicly available but was obtained by C&EN, Moure-Eraso says EPA had interfered in three CSB accident investigations and threatened a CSB investigator with a grand jury subpoena, demanding his testimony as well as “all notes, audio recordings, and transcripts of every interview” obtained in CSB’s investigation of the August 2012 fire at Chevron’s Richmond, Calif., refinery.

This approach, Vitter said, would “fundamentally threaten” CSB’s ability to conduct independent accident investigations. If EPA were successful, Vitter warned, the agency would shut down CSB’s ability to obtain information, because witnesses would fear criminal prosecution by EPA.

In his February letter, Moure-Eraso also notes that the congressional intent when creating CSB in 1990 was to form an independent investigative body to study the cause of chemical accidents and to make recommendations for new regulations and improved industry practices, not to issue fines. Subjecting CSB witnesses to EPA-led criminal investigations would turn that intention on its head, he says.

Moure-Eraso’s letter accuses EPA of “repurposing” CSB investigations despite having 400 times as many employees and a budget 750 times the size of CSB’s. Ironically, Moure-Eraso notes in the letter that Congress had directed EPA to provide CSB with support, not the other way around.

Breen refused to respond to Vitter about the situation, saying he would explain EPA’s views in private, not in public testimony. A clearly frustrated Vitter told Breen, “I don’t understand why you will not respond,” and said he would follow up in private.

As Moure-Eraso wrapped up his testimony, he described a bleak situation facing U.S. workers, industries, and communities near industrial plants. For the past five years, he said, CSB has prodded OSHA to expand its process safety enforcement and hire and train more inspectors for refineries and chemical firms. He noted that OSHA has but a “handful of inspectors with industrial process experience.”

In comparison, Moure-Eraso said the U.K. and other countries have developed large bodies of specialized industrial inspectors. The international insurance giant Swiss Re warned that U.S. refineries were experiencing accidents at a rate four times higher than the rest of the world.

OSHA did respond to CSB’s push for better oversight by creating a “national emphasis program” with heightened refinery inspections, but Moure-Eraso said OSHA soon canceled it because of resource constraints.

Moure-Eraso warned the committee that because of the number of accidents and a decade of flat funding, a crisis lies ahead for the board. “CSB has no capacity to undertake any new investigative work. The situation has been reached,” he said, “that I must tell this committee, that when the next serious accidents occur in the petrochemical industry—and believe me they are coming—we will not have the resources to deploy.”

More On This Story: Williams Investigation Under Way


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