Japan Today 
May 8, 2011
Tokyo Electric Power Co said the doors of the No. 1 reactor building connecting it to the adjacent turbine building at the crisis-hit Fukushima Daiichi nuclear power plant were opened Sunday, paving the way for the utility to proceed with efforts to stabilize the damaged reactor.
The move came after the government’s Nuclear and Industrial Safety Agency gave the go-ahead, saying it has assessed that opening the double-entry doors at the troubled facility would not have adverse impact on the environment.
TEPCO, said it plans to have workers go inside the reactor building at around 4 a.m. Monday to measure the levels of radioactivity inside.
The utility, which said earlier in the day that the level of radioactive materials in the No. 1 reactor building is low enough to pose no problem when it opens the doors, said it has notified related local governments after obtaining the agency’s approval.
Japan also informed foreign governments about the plan, said Goshi Hosono, one of Prime Minister Naoto Kan’s aides.
TEPCO said that even if radioactive substances are released from the No. 1 reactor building as a result of opening the doors, the radiation dose within the plant’s premises would be below 1 millisievert—the maximum level a person is to be normally exposed to annually.
On Thursday, TEPCO had workers install pipes connecting the No. 1 reactor building with a ventilator to filter out radioactive substances to reduce the high radiation levels inside the unit and make it possible for workers to enter the site without the risk of exposure to high doses of radiation.
The company said it determined after measuring the concentration of radioactive substances in air sucked out of the building that the doors can be opened. The ventilation was stopped and some of the pipes were removed Sunday night, it said.
Through the opened door, workers would soon able to go in and out of the building to begin work to build a new cooling system for the reactor, the most severely damaged at the six-reactor plant, which lost cooling functions in the March 11 quake and tsunami.
TEPCO said it will study the levels of radiation and radioactive substances in the building again after the doors are opened to take necessary protective measures for workers.
Meanwhile, the utility said radioactive strontium about 100 times the normal levels was detected in soil inside the Fukushima Daiichi plant.
At the plant’s No. 3 reactor, the temperature of its pressure vessel has again begun to rise, measuring 217 C at its upper part Sunday evening from 163 C at 11 a.m. Saturday, prompting the firm to enhance monitoring, though it is still lower than the 286 C in normal operation, it said.
In a related development, the government has decided to allow the fishery industry to operate in waters outside a 30-kilometer radius from the plant, including fishing and removing rubble from the sea, as exposure to radiation through such activities is estimated at up to 1.43 millisieverts per annum, officials said Sunday.