LM Otero/AP An investigator pauses while sifting through the debris of the destroyed fertilizer plant in West, Texas, May 2. Investigators face a slew of challenges in figuring out what caused the explosion at the fertilizer plant that killed 14 people.

The Texas fertilizer plant that exploded two weeks ago, killing 14 people and injuring about 200, was a repeat target of theft by intruders who tampered with tanks and caused the release of toxic chemicals, police records reviewed by Reuters show.

Police responded to at least 11 reports of burglaries and five separate ammonia leaks at West Fertilizer Co over the past 12 years, according to 911 dispatch logs and criminal offense reports Reuters obtained from the McLennan County Sheriff's office in Waco, Texas, through an Open Records Request.

Some of the leaks, including one reported in October 2012, were linked to theft of or interference with tank valves.

According to one 2002 crime report, a plant manager told police that intruders were stealing four to five gallons of anhydrous ammonia every three days. The liquid gas can be used to cook methamphetamine, the addictive and illicit stimulant.

In rural areas across the United States, the thriving meth trade has turned storage facilities like West Fertilizer Co and even unattended tanks in farm fields into frequent targets of theft, according to several government and fertilizer industry reports issued over the past 13 years.

The cause of the April 17 blast at the plant in the town of West is still being probed, and investigators have offered no evidence that security breaches contributed to the deadly incident. There also is no indication that the explosion had anything to do with the theft of materials for drug making. Anhydrous ammonia has been ruled out as a cause because the four storage tanks remained intact after the blast, said Rachel Moreno, a spokeswoman for the Texas Fire Marshal's Office.

Many leads

Investigators are pursuing about 100 leads, including a call to an arson hotline and a tip that there had been a fire on the property earlier on the day of the explosion, according to Moreno. Authorities have not said whether either tip was credible. About 80 investigators from various state and federal agencies are contributing to the probe. They hope to determine by May 10 what caused the explosion, Texas Fire Marshal Chris Connealy said at a state legislative hearing on Wednesday.

A spokesman for the U.S. Department of Homeland Security, one of several state and federal agencies that monitor security at chemical plants, declined to answer questions about the breaches of security at West Fertilizer Co. State investigators also declined to comment.

Thefts of anhydrous ammonia are common in McLennan County, where burglars siphon fertilizer from trailer tanks into 5-gallon propane containers, said McLennan County Chief Deputy Sheriff Matt Cawthon, who took up the position in January.

After reviewing crime reports from the past 12 years and speaking to deputies who responded to some of the break-ins, Cawthon said security was clearly lax at the plant.

The perimeter was not fenced, and the facility had no burglar alarms or security guards, he said. "It was a hometown-like situation. Everybody trusts everybody."

Chemical safety experts said the recurrent security breaches at West Fertilizer are troubling because they suggest vulnerability to theft, leaks, fires or explosions. Apart from anhydrous ammonia, the company stored tons of ammonium nitrate, a fertilizer that can be used in bomb-making. No thefts of that substance were reported to police.

"Regardless of what triggered this specific event, the fact that there were lots of burglaries and that they were after ammonia clearly shows this plant was vulnerable to unwanted intruders or even a terrorist attack," said Sam Mannan, a chemical process safety expert at Texas A&M University, who has advised Dow Chemical and others on chemical security.

New law

Owners of West Fertilizer, responding through a representative, declined to answer questions about specific instances of theft or the level of security at the plant. The company has encouraged its employees to share "all they know" with investigators, said Daniel Keeney, a spokesman for the company.

The current owners of West Fertilizer are Donald Adair, 83, and Wanda Adair, 78, who bought it in 2004. Calls to a number listed for previous owner Emil Plasek were not returned.

In a 2006 permit application with the Texas Commission on Environmental Quality (TCEQ), the company reported it would protect ammonia tanks against theft or tampering and conduct daily equipment inspections. A TCEQ spokesman would not comment about security measures. He said the agency's responsibility is to regulate emissions from the plant, not to oversee security.

Documents from the Texas Department of State Health Services show the West plant was storing 540,000 pounds of ammonium nitrate and 54,000 pounds of anhydrous ammonia in 2012. Ammonium nitrate was among the ingredients in the bomb used by Timothy McVeigh to blow up the Oklahoma City federal building in 1995, killing 168 people.

After that bombing, Congress passed a law requiring facilities that store large amounts of the chemical to report to the DHS and work with the agency to ensure proper security measures are in place to keep it out of criminal hands and protect against such attacks.

West Fertilizer did not report to DHS, despite storing hundreds of times more ammonium nitrate than the amount that would require it do so. Companies are required to report if they store at least 2,000 pounds of fertilizer-grade ammonium nitrate, or 400 pounds of the substance when it's combined with combustible material.

A 2005 U.S. Centers for Disease Control and Prevention (CDC) study identified hundreds of cases in 16 states where anhydrous ammonia was stolen for use in meth production. Some illegal labs mix anhydrous ammonia with ephedrine or pseudoephedrine and sodium or lithium to make methamphetamine, the U.S. Department of Justice reported in 2001.

In dozens of instances, the CDC said, the thefts by meth makers siphoning ammonia from tanks caused injuries or forced evacuations because gas was released into the environment. However, cases of ammonia theft have become less frequent since 2006, when new laws restricted the sale of pseudoephedrine, which is found in some common cold drug remedies, according to The Fertilizer Institute, an industry association.

Police records show West Fertilizer began complaining of repeated thefts from the facility in June 2001, when burglars stole 150 pounds of anhydrous ammonia from storage tanks three nights in a row. Nearly a year later, a plant manager told police that thieves were siphoning 4-to-5 gallons of the liquefied fertilizer every three days.

Randy Plemons, who was chief deputy sheriff during the years when the thefts occurred, declined to discuss specifics of his agency's response to the repeated break-ins.

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"Whenever we were notified of the burglaries and thefts we responded to those," he said. "I can't speak to every offense."

Company owners downplayed security risks in documents submitted to the Texas Commission on Environmental Quality in 2006, saying thefts had dropped to zero over the preceding 20 months as meth makers now had found a substitute for anhydrous ammonia available at garden nurseries or major retailers.

Very strong odor

Yet burglars and trespassers continued to target the facility. Following a series of break-ins in late 2008 and early 2009, including one where a trespasser visited pornographic websites on a secretary's computer, police told plant manager Ted Uptmore -- who has worked at the company for decades -- to install a surveillance system. Later documents indicate the company complied. Uptmore did not respond to phone calls seeking comment for this story.

The last record of tampering was in October 2012, when a 911 caller reported an odor "so strong it can burn your eyes." The firm dispatched Cody Dragoo, an employee often sent after hours to shut leaking valves and look into break-ins. That night, he shut off the valve but reported it had been tampered with.

Two weeks ago, Dragoo, 50, was among those killed in the blast while responding to the fire.

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