Still image from Tepco robotic camera showing Unit 3 storage pool for high-level radioactive waste largely clogged with debrisThe London Telegraph has posted video released by Tokyo Electric Power Company from early May, showing the reactor Unit 3 high-level radioactive waste storage pool at Fukushima Daiichi largely crammed full of debris caused by the massive hydgrogen explosion which left the secondary containment building a pile of rubble. Incredibly, Tepco and Japanese federal government officials have claimed the high-level radioactive waste in the pool remains largely intact, despite the explosion and resulting aftermath visible in the pool. A YouTube video shows the explosion of March 14th at Unit 3 -- the second of four such explosions at Fukushima Daiichi. Unit 1 exploded first on March 12th, followed by Unit 3 on march 14th. Unit 2's explosion occurred within the primary containment structure, severely damaging it, creating pathways for release of large-scale, catastrophic radioactivity releases into the environment. Unit 4's explosion was at first believed to have been caused by a boiling dry of the high-level radioactive waste storage pool, followed by a fire within the waste itself; however, the U.S. Dept. of Energy now theorizes that hydrogen gas from Unit 3 may have travelled through a common venting system, rather than out their common smokestack, into Unit 4's secondary containment reactor building , blowing it up.