The Japanese government is reducing the size of the evacuation zone around the devastated Fukushima Daiichi nuclear plant, destroyed by the March 11, 2011, earthquake and tsunami. Above, workers operate heavy machinery to remove debris near the nuclear power plant, February 24, 2015. Toru Hanai/Reuters

The Japanese government Friday eased evacuation orders for towns not seriously contaminated by the 2011 Fukushima Daiichi nuclear power plant disaster. The government lifted evacuation orders for parts of Kawamata, Namie and Iitate, Kyodo News reported. The order also frees a large part of Tomioka on Saturday.

The action reduces the evacuation zones by two-thirds but it was unclear whether residents actually would return to their homes because of radiation fears and a lack of amenities like schools. The most seriously contaminated areas remain off-limits.

Read: Nuclear Disaster Evacuees Welcomed Home By Cherry Blossoms

The nuclear power plant suffered a meltdown following a March 11, 2011, earthquake and tsunami, which killed tens of thousands and displaced 250,000 residents. Efforts to clean up the plant, which could top $189 billion and take decades, have proved problematic.

The reduction of the evacuation zones will allow the government to shift its focus to the heavily contaminated areas near the No. 1 nuclear reactor and infrastructure building, Asahi Shimbun reported. Decontamination work in nine of the 11 municipalities most affected has been completed.

The government has been removing soil, fallen leaves and other contaminated materials from residential areas, roads, rice paddies and fields since 2012 at a cost of $23.56 billion. The government hopes to make the rest of the area habitable by 2022.

Read: Deadly Nuclear Radiation Levels Cause Robot Failures To Mount At Power Plant

The Asahi Simbun reported last week using remote-controlled robots to collect data on radiation levels and locations of the 600 tons of melted nuclear fuel has yielded little information because the devices have suffered radiation damage or been unable to complete their tasks for other reasons.

The lower part of the containment vessel for the plant’s No. 1 reactor is submerged and experts say fuel debris likely is below the surface. Though a robot was able to measure underwater radiation levels for five days recently, it was unable to take pictures of the debris, the newspaper reported.

The Tokyo Electric Power Co. (Tepco), which operated the plant, hopes to begin removing molten nuclear fuel by 2021, but first that fuel needs to be located and its condition assessed. In trying to assess the No. 2 reactor, a robot got stuck in deposits after traveling just six feet. The No. 3 reactor has yet to be assessed. Reactor Nos. 4, 5 and 6 were not operating at the time of the disaster.

The International Research Institute for Nuclear Decomissioning has been working on new robots for the project since 2014 at a cost of $62 million, with two years left on the contract.

TechCrunch said authorities now are wondering whether redirecting the funding to chemistry, biology and so-called safe containment — building a sarcophagus like the one that surrounds Chernobyl — would be a better way of dealing with the disaster than investing in more robots.

Former Japanese Prime Minister Jaoto Kan on Monday blamed Tepco in part for the severity of the contamination, telling the Cornell Daily Sun the utility was slow to relay crucial information to him as the disaster unfolded. He also said though the country was prepared to deal with natural disasters like the earthquake and tsunami, it had no expertise in dealing with a nuclear disaster. Kan was in Ithaca, New York, for a scheduled lecture.