(USA Today)-- The fertilizer plant that exploded in West, Texas, killing more than 30 people and causing widespread damage was cited and fined in 2006 for federal environmental violations, the Environmental Protection Agency said Thursday.
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West Chemical and Fertilizer was fined $2,300 in March 2006 for failing to update a risk management plan and for having poor employee-training records and no formal written maintenance program, according to the EPA. The company later certified it had corrected the deficiencies, the EPA said.
The EPA also Thursday said it had deployed a team to monitor air quality in the vicinity of the explosion and fire. The Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) sent a "National Response Team" to the site to help investigate the cause of the catastrophe. The team includes forensic chemists, explosives-detection canines and other specialists to help reconstruct the scene and gather evidence, ATF spokesman Franceska Perot said.
WATCH: West Texas explosion video from 3 different angles
The U.S. Chemical Safety Board, an independent federal agency that investigates chemical accidents, also sent an investigation team.
The Occupational Safety and Health Administration (OSHA) sent compliance officers, and "is working jointly with the Environmental Protection Agency and the Chemical Safety Board to try to determine the cause of the explosion, if any violations of health and safety standards occurred, and lessons learned," said OSHA spokesman Jesse Lawder. OSHA last inspected this facility in 1985.
Air quality and safety of fertilizer facilities are regulated by both federal and state governments, said Kathy Mathers, vice president of public affairs for the Fertilizer Institute, the trade association representing the fertilizer industry. Local governments are more likely to oversee siting of where retail facilities that distribute fertilizer to farmers and other customers are located, she said.
"We frequently see local municipalities and citizens' groups getting very involved in determining where these facilities are," she said.
She said she had been in the fertilizer industry for 23 years and had never seen an explosion and fire of this magnitude. Damage was widespread to homes, a nursing home and a middle school in the town of about 2,850 people.
Feed and fertilizer distributors such as West Fertilizer Co. are registered with the Texas Feed and Fertilizer Control Service, which also inspects them. West is one of 592 such establishments registered with the agency, created in 1899, says Tim Herrman, the Texas State Chemist who directs the service based in College Station.
On its web page, the Feed and Fertilizer Control Service shows 14 feed and fertilizer investigators, each responsible for certain counties in the state. Texas has 254 counties.
"It's a complex facility," Herrman said of West Fertilizer. "Each of the different types of structures could fall under a different regulatory authority. It has fertilizer and grain. And they're also licensed as a feed establishment because of the grain tanks."
According to the service's 2012 annual report on fertilizer distributors, West Fertilizer had two chemical-related violations and one registration violation, from September 2011, to September 2012.
"We are in the firms multiple times in a year. We were in this firm just recently," Herrman says, declining to elaborate on how recently. "It's very clearly defined in the law and rules what they're obliged to do, and we make sure they do all of it."
Attorney Terrence Welch of Richardson, Texas, an expert in Texas zoning laws, said it's not surprising that homes and schools would be located near industrial facilities in small towns, many of which grew up around railroad tracks.
"Even though cities have zoning powers, the houses have been there sometimes long before cities adopted zoning ordinances," he said, "I grew up in the Midwest, and it's the same way there, too."
As to why a school may have been near the fertilizer facility, spokesman DeEtta Culbertson of the Texas Education Agency in Austin says there are no state regulations about school locations.
"It's a local issue," she said.
Jerry Hagins, a spokesman for the Texas Department of Insurance, which oversees the State Fire Marshal's Office, says it's up to local fire authorities to conduct safety inspections of such facilities.
"The local authorities have jurisdiction. It's an industrial plant within the city limits of West. It would be the West Volunteer Fire Department with the jurisdiction," he said.
However, Hagins says his office is involved in the explosion investigation.