Fukushima , Japan ( CNN ) -- After talking about spent nuclear fuel rods at Fukushima for more than two years , it is slightly disconcerting to suddenly be a few meters from them . Some 1,500 fuel units to be exact , rest in a cooling pool within the damaged Reactor 4 building . Tokyo Electric Power Co. ( TEPCO ) , the crippled nuclear plant 's operator , escorted a small group of journalists including CNN , into the heart of the building to show us the preparations being made for an imminent and crucial operation . TEPCO says it will start the difficult process of removing this nuclear fuel in the coming days and transport it to a more stable location 100 meters away . Officials say they have done this more than 1,200 times before under normal circumstances . But considering there was an explosion in the Reactor 4 building days after the March 2011 earthquake and tsunami , these are n't normal circumstances . `` We have removed large debris ( from the pool ) and cleaned it with a water vacuum , '' said plant chief Akira Ono . `` But there is a possibility that very small pieces of debris were left behind . `` If they are stuck between the channel box and the rack , we may not remove fuel smoothly , which will affect the operation 's smoothness . In that sense , we are concerned . '' This would certainly be considered one of the more dangerous areas of the plant to work in . Half a dozen men were making final checks to the newly installed crane and hook that would lift the fuel rods from the pool into specially built containers for transportation . All are wearing full protective gear with dosimeters in their left chest pockets to monitor their daily exposure . In the four hours we were on site , our dosimeters showed we were exposed to 0.06 millisieverts , the equivalent of two week 's radiation away from Fukushima , a TEPCO official told me . Driving around the plant , evidence of the devastating tsunami is still perfectly clear two and a half years later . Some building structures remain damaged , as steel girders lie broken and untouched . The cleanup operation is so immense that only essential maintenance is tackled . We were also escorted to the H4N tank area , the scene of a recent leak of contaminated water . The plant is home to about 1,000 storage tanks , holding the irradiated water that has been used to keep the nuclear reactors cool . From the 400,000 ton capacity , TEPCO says 370,000 has already been used . Work is also continuing to try and increase the capability of the ALPS water decontamination system , currently a fairly slow process . Close to the ocean front , we were shown the latest efforts to stop radioactive groundwater from seeping into the Pacific , estimated at around 300 tons a day . The tips of yellow and pink ribbons sticking up from the earth indicate where an underground barrier has been constructed . Liquid cement has been injected into the ground to try and keep the water within the plant itself . The coming days will be crucial to the efforts to stabilize the nuclear power plant . TEPCO rejected alarmist comments from some quarters that any mistake in removing the spent fuel rods could spark another nuclear disaster . Ono told reporters on site , `` I believe it 's nearly impossible . '' Time will tell .
Operators of crippled Fukushima nuclear plant to remove fuel rods . Nuclear fuel units found in a pool within damaged Reactor 4 building . Japanese nuclear plant damaged by earthquake and tsunami in March 2011 . Process to remove the spent fuel is complex and potentially dangerous .