In a report released Wednesday, state officials said heavy corrosion on natural gas pipes may have caused gas lines to fail in the early morning hours of July 24, 2002, filling the building with the explosive gas.

The gas exploded, levelling the 65 Main St. building and killing Violet Carey, 5, and her 4-year-old sister, Iris.

The girls' parents, Tara and Heath Carey, and 10 other people who lived in the building, survived the blast.

But that potentially fatal mix of conditions may be more common than most people think, said Alan Cantor, a lawyer representing Tara and Heath Carey.

"I think people do need to have some concern," he said. "If it's my house, and I see rust or corrosion, then it's a concern to me. I know I'd feel a lot better if I call somebody and have them take a look at it."

Under federal law, Cantor said, the utility is required to check all pipes and fittings from gas mains to meters for corrosion and leaks every three years.

But according to the state Department of Telecommunications and Energy's report this week, gas company NStar had no records of the inspections.

The DTE has proposed NStar pay a $200,000 fine for the alleged violations, but officials yesterday refused to discuss the report's findings, or whether corroded pipes in other homes could lead to similar explosions.

"We're not going to talk about this at all," DTE Executive Director Timothy Shevlin said. "It's a pending matter going on now."

NStar officials did not return calls seeking comment on the report.

Though Cantor urged homeowners to check the pipes in their basements, he was quick to warn against panic.

"I don't think anyone needs to panic, but I do think it would be prudent for homeowners to make a visual inspection of their interior gas piping," he said. "If they do have any specific concerns, call the appropriate person to come and check it out."

Cantor's advice was reiterated by local public works and building officials.

Though most shied away from laying any specific blame for the deadly blast, most that agreed residents concerned about their natural gas systems should go to the source -- NStar.

"They should call NStar when they smell anything, especially when they smell gas," Hopkinton DPW Director J.T. Gaucher said.

His department doesn't perform annual maintenance checks on gas lines serving homes or businesses, but Framingham Building Commissioner Joe Mikielian yesterday said finding heavily corroded pipes would be a concern if they did.

"That's a red flag," he said. "Yeah...I would look at it, (or) get a plumber or gas fitter to look at it."

Like most concerns with natural gas, however, the problem ultimately would land at NStar's door.

If inspectors have worries about pipes, "it's got to get to NStar as soon as possible." Either he or an inspector would bring a problem to NStar, Mikielian said, and the company would take what action is necessary.

"But it's unusual, because it's almost a rarity," he said. "It's really the responsibility of the gas company and the homeowners. If the homeowner thinks there's a problem, call the gas company, or call us, and we'll go out and inspect it, and if it needs to be repaired, we'll make sure it gets repaired."

(Peter Reuell can be reached at 508-626-4428, or at preuell@cnc.com)