FirstEnergy Corp. faces the likely prospect of going through much of the summer -- prime time to sell electricity for air conditioning -- without the use of its damaged Davis-Besse nuclear power plant.

The initial hope was to finish the repairs by the end of June and avoid having to spend tens of millions of dollars to buy electricity elsewhere.

And that assumed the damage could be repaired without completely replacing the massive reactor vessel head.

Now, no one knows just when the job will get done.

FirstEnergy's original June timetable also depended upon federal regulators giving the OK for unprecedented repairs on the vessel head, a key safety device that has been damaged by boric acid.

That timetable, which was always tentative, depended upon FirstEnergy having its repair plans before the Nuclear Regulatory Commission by now.

Instead, it will be a couple more weeks before FirstEnergy submits those plans to the NRC, a company spokesman said yesterday.

``There will be some impact on the (restart) schedule,'' said Davis-Besse spokesman Richard Wilkins. He said he didn't know how long the delay could be, but that FirstEnergy staff were working to come up with a detailed repair plan that will answer any NRC concerns.

It appears that restarting the Lake Erie shorefront plant in Northwest Ohio will be pushed back at least into late July -- if the NRC approves the repairs.

FirstEnergy has estimated that it will cost the company between $10 million and $15 million a month in additional energy costs for each month that Davis-Besse can't produce electricity. Hot, humid summer weather drives up the demand for electricity as air conditioning gets cranked up in homes and businesses.

NRC: Time not factor

FirstEnergy had estimated the NRC will finish its review of the repair plans four weeks after receiving them, Wilkins said.

An NRC official yesterday said, however, that reviewing the repair plan conceivably could take as long as eight weeks, and that Davis-Besse will need to pass other inspections before being allowed to restart. The plant in Oak Harbor powered down on Feb. 16 for refueling and has stayed closed since the acid damage was found in March.

``It's hard to say how long it's going to take,'' said Brian Sheron, associate director for project licensing and technical assessment at the NRC. He said a rough guess is that the NRC staff review of the Davis-Besse repair plan will take anywhere from four to eight weeks once it's submitted.

``We're obviously not going to try to purposively hold the plant up,'' Sheron said. ``But we don't feel compelled to meet the licensee's schedule.''

Even if the NRC approves the repairs, the federal agency has to convince itself that FirstEnergy has taken adequate steps to ensure that problems that led to the vessel head damage aren't repeated, he said.

For one thing, FirstEnergy still has to demonstrate to the NRC that it doesn't have other boric acid leaks elsewhere inside Davis-Besse, he said. ``They've got more work to do,'' Sheron said.

No danger of shortage

Even without Davis-Besse's more than 880 megawatts of power, which represents less than 8 percent of FirstEnergy's total generating capacity, FirstEnergy customers won't go without electricity. Instead, the utility will find alternate electricity supplies.

If the NRC doesn't approve the repairs, FirstEnergy may be able to buy another vessel head and modify it to fit the Davis-Besse reactor. That would push back restarting the plant at least 10 months, officials have said. FirstEnergy ordered a new reactor vessel head last fall, but that will take about two years to be delivered.

The company has estimated that repairing two acid-created cavities found on top of the vessel head could take as long as four weeks. FirstEnergy is proposing plugging one cavity with a 300- to 400-pound stainless steel disk.

In a related matter, FirstEnergy yesterday submitted a 165-page report to the NRC showing that boric acid leaks dating back at least four years began damaging the top of the 150-ton steel vessel head that covers the nuclear fuel. The acid is a component of the reactor coolant.

The report says, among other things, if plant operators had properly implemented a boric acid corrosion program early on, damage might have been avoided. FirstEnergy estimates repairs will cost at least $16 million.

The so-called ``root cause'' report describes in much greater detail than a preliminary report given weeks ago how the acid damaged the vessel head and went undetected until this year.

The company said in a press release that it has been taking numerous steps to prevent future problems at the plant.

No other nuclear power plants of similar design in the United States has shown similar damage to date, the NRC said.

FirstEnergy stock yesterday rose 55 cents to $32.95.