TOKYO (AP) ― A Japanese government panel says it will take at least 30 years to safely close the tsunami-hobbled Fukushima Dai-ichi nuclear power plant, even though the facility is leaking far less radiation than before and is considered relatively stable.

The plant, site of the world’s worst nuclear accident since Chernobyl in 1986, was severely damaged by Japan’s March 11 earthquake and tsunami. It suffered power outages, meltdowns and explosions that released radioactive material and forced tens of thousands of people to flee the area.

While officials say the plant, about 240 kilometers northeast of Tokyo, is now relatively stable, an expert panel named by Japan’s Atomic Energy Commission said it would likely take 30 years or more to safely decommission it. The panel made the estimate in the draft of a report to be completed by the end of the year. The draft was posted on the commission’s website over the weekend.

Plant workers are still struggling to contain radiation leaking from the plant, although the amount is far less than before.

The panel noted that it took 10 years to remove nuclear fuel after the 1979 Three Mile Island accident in the United States, and suggested that the process at Fukushima would be much more complicated and time-consuming.

It is also expected to be more costly. A report Saturday in the Yomiuri, a major newspaper, said independent experts believe the process will cost more than 1.5 trillion yen ($19 billion).

The massive earthquake and tsunami in March triggered meltdowns at three of the plant’s six reactors. Explosions also damaged their buildings, plus Unit 4 next to them.

Officials at Tokyo Electric Power Co., the utility that runs the plant, say they have largely succeeded in cooling the damaged reactors, meeting a goal of completing what is called a “cold shutdown.” But extensive repairs and safety measures must still be carried out. The panel said removal of the fuel rods at Fukushima would not begin until 2021, after the repair of the plant’s containment vessels.

As a stopgap measure, one of the damaged units now has an outer shell made of airtight polyester designed to contain radioactive particles inside the building. Similar covers are also planned for other buildings.

Government officials must also deal with a massive decontamination effort in areas around the plant. A 20-kilometer exclusion zone around the facility remains in effect.

While the worst appears to be over, recent discoveries of radiation “hot spots” in and around Tokyo have caused fears among people there, with many concerned parents routinely checking their neighborhoods for radiation.

In most cases, the readings have been below internationally accepted annual limits, but critics say that the standard exceeds Japan’s cap before the accident and that the government should expand the scope of decontamination.

The magnitude-9.0 earthquake was the strongest to hit Japan on record, and left more than 21,000 people dead or missing. The tsunami that followed engulfed the northeast and wiped out entire towns.