WASHINGTON D.C. (CBS 11 NEWS) – Experts blamed lax regulations and a patchwork of safety standards with many large holes for leading to the fertilizer plant explosion last April that killed 15 people in West.

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The comments came during a hearing on Capitol Hill by the Senate Committee on Environment and Public Works.

Click For Comprehensive Coverage of the West Fertilizer Plant Explosion

The committee chairwoman, Senator Barbara Boxer, Democrat of California, asked if there is a particular regulation that if enforced could have prevented the disaster in West.

Dr. M. Sam Mannan, a professor specializing in process safety at Texas A&M, told Senator Boxer about an existing rule from OSHA regulating the storage of ammonium nitrate, the chemical that exploded at the plant.  “It says ammonium nitrate shall be in a separate building or shall be separated by approved firewalls.”

In West though, the ammonium nitrate was stored in combustible wooden bins in a wooden building without sprinklers.

A fire there caused the chemical to explode.

But the last time OSHA inspected the West plant came in 1985 — nearly 30 years ago.

Mannan said, “If OSHA had some competent inspectors who had gone in there on a regular basis and made that enforcement, yes, they would have looked at that.”

The chairman of the U.S. Chemical Safety Board, Rafael Eraso-Mauro agreed.  “This situation must be addressed.  Preventing the risk of a fire eliminates the potential for an explosion like we saw in West.”

Senator Boxer also sharply criticized another government agency, the EPA, for not listing ammonium nitrate as an extreme hazard. That would have required the company to develop a disaster plan for a worst case scenario. The Chemical Safety Board urged the EPA to do so 11 years ago.

Boxer told Barry Breen, an EPA deputy administrator, “I’m unsympathetic to the attitude that I hear which is a lack of urgency cause lives are being lost and recommendations were being made a long time ago, and nothing’s happening.”

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Breen responded by saying the agency does have a sense of urgency.  “The important thing is to get it right in addition to getting it fast.”

But Senator Boxer interrupted him, “Fast? It goes back to 2002, please!”

Breen told Senators that the agency issued an alert about the chemical and that it can be found on the agency’s website.  “It warns a fire involving ammonium nitrate in an enclosed space could lead to an explosion.”

Senator Boxer asked, “When did you do that?”

Breen replied, “December, 1997.”

Boxer answered, “This adds even more impact to the fact that you’ve done nothing in terms of your risk management plan. If you knew it back then even before 2002.”

She then put the EPA on notice.  “Let’s fix it, and you have the tools sir, and we’re going to work with you, and if we have to, against you.”

Senator Boxer pushed the EPA to regulate the storage of ammonium nitrate at facilities like West.

That could take up to 18 months to put in place even after the agency approves it.

Boxer also demanded the EPA issue another alert about the chemical.

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