UPDATE AS OF 11 A.M. EDT, FRIDAY, APRIL 15:
TEPCO also reports that radiation levels of Iodine-131 and Cesium-134 in water in so-called sub-drain pits have risen by up to 38 times during the past week.
The company is working to finish moving emergency diesel power generators and water injection pumps to higher ground and to bring in additional backup power trucks and fire engines as a precautionary measure. Work is also in progress to cross-connect external grid power lines to all four reactors.
The U.S. State Department has lifted its voluntary evacuation advisory for families of U.S. government employees in Tokyo and other Japanese cities, saying that while the situation remains serious, it is “dramatically different” now than it was on March 16, and health and safety risks are low for areas outside an 80-kilometer (50-mile) zone around the plant, which includes Tokyo. However, it has maintained its recommendation for U.S. citizens to avoid travel within the 50-mile zone.
TEPCO also reported on Friday it had conducted a 2-hour long unmanned helicopter flight over reactors 1 through 4 “to check the condition of the reactor buildings.” The helicopter is to fly again today. Video footage has not yet been released.
UPDATE AS OF 6:30 P.M. EDT, THURSDAY, APRIL 14: