LOUISVILLE, KY. (WDRB) -- An investigation into a natural gas explosion that destroyed a Louisville home identifies four "probable" safety violations by the Louisville Gas & Electric Company.

The explosion happened on December 6, 2011 in the 5200 block of River Trail Place.  No people were seriously injured, but a dog died in the explosion and fire.

Investigators with the Public Service Commission found that a high-pressure leak in a water line cut a hole in a gas main, letting gas into nearby homes.  The cause of the water line was not discovered.

The blast happened about 7 a.m., which was 2½ hours after the first LG&E worker arrived. 

Investigators say that worker did not take steps such as checking for gas in sewers to find out how far the gas had gotten, which would also allowed a safe perimeter to be established around the leak.

They also said although three nearby homes were checked and evacuated when gas was detected in them, a fourth home was not.  That home was where the three people inside the house had exploded had take refuge.  That house was checked a couple of hours later, gas was discovered, and it was evacuated.

The investigators reviewed LG&E's records and determined that the company had let pressure in the neighborhood's gas system regularly exceed allowable levels slightly, and did not take action to correct those levels when they were detected.

The violations could cost LG&E up to $25,000 for each day they occurred.

LG&E spokeswoman Chris Whelen says, "The important thing to note is that the fire marshal concluded that it was not a problem with our line, and that it was caused by an accident -- a water line ruptured our line.  Our employees were there, they were working quickly to find the leak.  So we're going to continue to look into it...it's an unfortunate incident, and safety's one of our core values, so we continue to find ways to improve safety."

Despite those alleged violations, the Public Service Commission's investigation did not say whether those violations led to the explosion.

A hearing on the case is scheduled for November 27, 2012.

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