"People's lives are devastated here. It's hard to imagine," he said.
The Wednesday night blast was apparently touched off by a fire, but it remained unclear what sparked the blaze. A team from the Bureau of Alcohol, Tobacco, Firearms and Explosives still had not been able to begin investigating the scene because it remained unsafe, agency spokeswoman Franceska Perot said.
The West Fertilizer Co. facility stores and distributes anhydrous ammonia, a fertilizer that can be directly injected into soil, and a blender and mixer of other fertilizers.
Records reviewed by The Associated Press show the U.S. Pipeline and Hazardous Materials Safety Administration fined West Fertilizer $10,000 last summer for safety violations that included planning to transport anhydrous ammonia without a security plan. An inspector also found the plant's ammonia tanks weren't properly labeled.
The government accepted $5,250 after the company took what it described as corrective actions, the records show. It is not unusual for companies to negotiate lower fines with regulators.
In a risk-management plan filed with the Environmental Protection Agency about a year earlier, the company said it was not handling flammable materials and did not have sprinklers, water-deluge systems, blast walls, fire walls or other safety mechanisms in place at the plant.
State officials require all facilities that handle anhydrous ammonia to have sprinklers and other safety measures because it is a flammable substance, according to Mike Wilson, head of air permitting for the Texas Commission on Environmental Quality.
But inspectors would not necessarily check for such mechanisms, and it's not known whether they did when the West plant was last inspected in 2006, said Ramiro Garcia, head of enforcement and compliance.
That inspection followed a complaint about a strong ammonia smell, which the company resolved by obtaining a new permit, said the commission's executive director Zak Covar. He said no other complaints had been filed with the state since then, so there haven't been additional inspections.
At the church service, the Rev. Ed Karasek told the hundreds gathered that it would take time for the community to heal.
"Our hearts are hurting, our hearts are broken," he said. The non-denominational gathering for prayer and song was intended to honor those who rushed toward the danger and those who found themselves too close.
"I know that every one of us is in shock," he said. "We don't know what to think."
"Our town of West will never be the same, but we will persevere."
Associated Press writers Michael Brick, Nomaan Merchant and Angela K. Brown and video journalists John L. Mone and Raquel Maria Dillon in West; writers Jamie Stengle in Dallas, Ramit Plushnick-Masti in Houston and Seth Borenstein Washington contributed to this report.
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