Nov. 7--In March 2006, a disgruntled worker drilled a tiny hole in a crucial pipe at the Turkey Point nuclear power plant. Ultimate cost: At least $6 million. Big question: Who should pay?

Customers should, says Florida Power & Light.

Not so, says the Office of Public Counsel, which represents the state's utility customers. FPL should pay because it was responsible for allowing a troubled worker inside a highly sensitive area, the Public Counsel says.

The Counsel points to a newly obtained FBI report that reveals the prime suspect in the case was a contract employee who drilled the hole because he was angry with the utility. The FBI says he failed an FPL psychological test, had a criminal background and was heard complaining loudly that FPL was mistreating him.

Those revelations sparked an intense debate Wednesday and Thursday before the Public Service Commission in Tallahassee about who should bear the costs of the hole and about the fundamental safety of nuclear facilities.

Many of the costs associated with the incident are unknown, such as the expense of the 1,100-plus interviews conducted by the FBI and a parallel investigation by the Nuclear Regulatory Commission. What is known is that while the power plant was shut down for the investigation and repairs, FPL had to spend $6.2 million to buy power elsewhere.

The $6.2 million has already been paid by FPL customers. Stephen Burgess, representing the Public Counsel, is trying to get that money back for customers, with interest, arguing that the new documents show proper procedures should have kept the suspect out of the plant.

FPL attorney John Butler insisted the utility properly followed all guidelines set by nuclear regulators. "Somebody slipped through the cracks," he said. "We wish it weren't the case."

The unhappy worker has never been publicly identified. He first denied drilling the hole, but after a lie-detector exam, he "admitted to being in the immediate area of where the hole was found," the FBI report said.

The suspect "further admits that he could have in fact drilled into the insulation covering the pipe, directly above the hole," according to the FBI report. 'When asked whether he could have drilled the hole by accident, the examinee said that 'nothing is out of the realm of possibility,' but the chance of him doing it [accidentally] was less than 5 percent."

Last year, federal authorities decided not to prosecute because they could not prove criminal intent.

The man, a sheet metal worker described by the FBI as a Bud Light drinker from Indiana with a late-model pickup truck, was visiting Florida when he heard Turkey Point was hiring.