(CNN) -- Operators of the crippled Fukushima nuclear plant in Japan have started the dangerous task of removing fuel rods from a damaged reactor, the Tokyo Electric Power Co. (TEPCO) said Monday.
The procedure is considered a milestone in the estimated $50 billion cleanup operation more than two years after a massive earthquake and tsunami brought disaster to the facility.
When the tsunami swamped the plant, located 149 miles (240 kilometers) north of Tokyo on Japan's eastern seaboard in March 2011, it cut the power to vital cooling systems for the three reactors in use at the time. This resulted in the second-worst nuclear accident in history -- after Chernobyl in the former Soviet Union in 1986 -- as the reactors melted down and leaked radioactive material into the atmosphere.
On Monday, TEPCO revealed "preparatory work" was underway, with a remote-controlled crane lowered inside Reactor 4. Some 1,500 spent fuel units will then be lifted from the cooling pool in specially-designed containers, or casks, and closed with a lid. Following decontamination, these casks will be taken down to ground level and transported to the common spent fuel pool on a trailer.
The entire removal of all fuel inside the Unit 4 spent fuel pool is expected to take until the end of 2014, TEPCO says.
The Fukushima cleanup has been beset by numerous problems, with TEPCO frequently criticized for its handling of the disaster. Earlier this year, Japan's Trade and Industry Minister, Toshimitsu Motegi, compared its "stopgap approach" to a game of "Whack-a-mole." The government has since stepped in and pledged $470 million to try to tackle the leaks, through measures, which by its own admission are unconventional and untested.
TEPCO has been pumping huge volumes of water into the plant -- hundreds of tons daily -- to cool the crippled reactors that once powered the plant.
But this water, which becomes highly radioactive once it comes into contact with the plant's fuel rods, has been stored in makeshift, hastily-built storage tanks around the site -- about 1,000 so far -- containing enough irradiated water to fill about 160 Olympic-sized swimming pools, with about 400 tons added to the tanks daily.
Scientists who monitor radiation levels offshore have pointed to evidence of an ongoing leak for more than a year, but it was only recently that TEPCO admitted it was occurring.
Last month, TEPCO said one of the storage tanks at the site had leaked 300 tons of toxic water, prompting Japan's nuclear regulator to declare the situation a Level 3 serious incident, its most serious assessment since the 2011 meltdown.
It has since stated that several tanks and pipes at the plant are suspected of leaking toxic water.
Michael Friedlander, a nuclear engineer and former U.S. power plant operator, told CNN in September that the eventual failure of the tanks years after they were deployed on a supposedly temporary, emergency basis is illustrative of TEPCO's ad hoc, unsustainable response to the disaster.
"Given the cards they were dealt, building a tank farm to hold the water in the heat of the emergency, there was really there only one option, so I don't fault them for that," he said.
But beyond the emergency response, TEPCO had demonstrated no long-term vision for dealing with the problem, he said.
CNN's Junko Ogura in Tokyo contributed to this report.