The operator of Japan's crippled Fukushima Daiichi nuclear plant detected the highest radiation levels at the facility since the initial earthquake and tsunami five months ago, a company spokesman said Tuesday.
The ultra-high levels of radiation were measured Monday afternoon on the grounds of the facility, between reactors No. 1 and 2, CNN reported.
The power company immediately cordoned off the area, a spokesman for the Plant operator Tokyo Electric Power (Tepco) said.
The radiation levels -- 10,000 millisieverts per hour -- are high enough that a single 60-minute dose would be fatal to humans within weeks, MSNBC reported. Tepco said Tuesday it found another spot on the ventilation stack itself where radiation exceeded 10 sieverts per hour, a level that could lead to death after just several seconds of exposure.
Workers at Daiichi are only allowed to be exposed to 250 millisieverts of radiation per year, MSNBC reported. Tepco, which provides power to Tokyo and neighboring areas, said it had not detected a sharp rise in overall radiation levels at the compound.
See GlobalPost dispatch: Japan's nuclear gypsies: a day in the life: "In addition to 373 staff employed by the plant's operator, Tokyo Electric Power (TEPCO), the Fukushima Dai-ichi plant is teeming with 2,529 contract workers, all braving dangerously high radiation on what must be the most hazardous industrial site on earth."
"The high dose was discovered in an area that doesn't hamper recovery efforts at the plant," Tepco spokesman Junichi Matsumoto told reporters on Tuesday.
The Fukushima Daiichi disaster occurred when a 15-meter (48-foot) tsunami slammed the coastal plant after northern Japan's historic March 11 earthquake.The flooding knocked out the cooling systems for the three operating reactors and their associated spent fuel pools, causing the reactors to overheat and hydrogen gas explosions that blew apart the building housing reactors No. 1 and 3, CNN reported.
Another hydrogen blast was believed to have damaged the inside of the No. 2 reactor, while engineers struggled to manage an estimated 100,000 tons of highly contaminated water that was used to cool the reactors during the emergency.
Tepco projects the situation won't be fully over until sometime between October and January. The disaster has caused Japan to rethink its commitment to nuclear energy, and Germany has since announced plans to abandon atomic power entirely by 2022.