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Texas Explosion Facts Emerge

Investigation: Ammonium nitrate, lack of regulatory oversight are likely causes of West, Texas, tragedy

by Glenn Hess , Jeff Johnson
April 26, 2013 | A version of this story appeared in Volume 91, Issue 17

Credit: Adrees Latif/Reuters/Newscom
The day after the West Fertilizer facility explosion, investigators search for clues among the remains.
This is a photo of the remains after a fertilizer explosion in Texas in April.
Credit: Adrees Latif/Reuters/Newscom
The day after the West Fertilizer facility explosion, investigators search for clues among the remains.

Facts have slowly emerged over the past week about the devastating accident at West Fertilizer Co. in West, Texas. As federal and state investigators examined the scene, the exact cause remained unclear, as did the role proper regulatory oversight might have played in avoiding the tragedy.

At least 15 people, mostly firefighters, lost their lives, and 200 residents were injured in a fire and massive explosion that completely destroyed the facility on April 17. According to state and federal records, the retail facility stored some 270 tons of ammonium nitrate and 54,000 lb of anhydrous ammonia for sale to local farmers. Ammonium nitrate is an explosive sometimes used by terrorists and the source of numerous industrial accidents and thousands of deaths worldwide.

On the night of the accident, the facility caught fire. Some dozen firefighters and emergency responders fought unsuccessfully to control the fire. Conditions worsened and officials rushed to evacuate the area, which included a school, a nursing home, and private residences. The facility exploded before the evacuation was complete, leveling the surrounding area and leaving a 93-foot-wide crater, according to a reporter who gained access to the site.

The facility appeared not to segregate ammonium nitrate, nor did it have automatic sprinkler systems, structural fire barricades, or other mechanisms to limit fires. Whether first responders were aware of what was in the warehouse and its potential for explosion is unknown.

Like some 6,500 other U.S. fertilizer distributors, the facility received ammonium nitrate in the form of prills—spherical particles. Even in prill form, ammonium nitrate readily burns. Once the chemical reaches a critical temperature, it explodes.

Use of ammonium nitrate in the U.S. is declining. It makes up just 2% of directly applied nitrogen products, fertilizer industry representatives say. According to the Department of Agriculture, ammonium nitrate use has dropped by half since 2005. Still, 719,000 tons was applied in 2010, the last year for which figures are available.

Ammonium nitrate storage and use are controlled by state and federal regulations. However, it appears that West Fertilizer’s reports to regulators held conflicting information about what materials and quantities were stored, so this small retail distribution facility may not have triggered regulators’ notice.

The Department of Homeland Security (DHS) has clear authority over this facility. Under the Chemical Facility Anti-Terrorism Standards (CFATS) program, fertilizer plants and retail facilities must notify DHS when they annually produce, store, or distribute 400 lb or more of ammonium nitrate and 10,000 lb or more of anhydrous ammonia. The West facility exceeded both thresholds, but it had never filed a report with DHS.

“Although it’s still early, it seems this operator was willfully off the grid,” says Rep. Bennie G. Thompson (D-Miss.), the top Democrat on the House of Representatives Homeland Security Committee. “We understand that DHS did not even know the plant existed until it blew up,” Thompson says.

The West Fertilizer facility is not currently regulated under CFATS, acknowledged DHS spokesman Scott McConnell, and is not among the 4,380 high-risk facilities covered nationwide. DHS is now looking into whether West Fertilizer should have submitted a questionnaire that the department requires to determine whether a facility poses a high risk. DHS has the authority to fine or shut down a facility that fails to report holding large volumes of hazardous chemicals.

Thompson asserts that DHS’s failure to oversee the Texas plant calls into question the fundamentals of CFATS: “I strongly believe that had DHS personnel worked with the plant owners to identify vulnerabilities and put safeguards in place, as DHS does at thousands of other plants, the loss of life and destruction could have been far less.”


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