Radioactive Water Removal Underway, Fresh Seawater Pollution Found

The plant operator Tokyo Electric Power Co. said early Monday that the concentration of radioactive substances of a pool at the No. 2 reactor was 100,000 times higher than usual for water in a reactor core, correcting its earlier analysis of 10 million times higher.

Chief Cabinet Secretary Yukio Edano told a press conference that the highly radioactive water found at the basement of the No. 2 reactor's turbine building is ''believed to have temporarily had contact with fuel rods (in the reactor's core) that have partially melted.''

The Nuclear Safety Commission of Japan, a government panel, said Monday in its recommendations to Prime Minister Naoto Kan that highly radioactive water in the No. 2 reactor's containment vessel could have directly leaked, raising concerns that polluted water could spread to the building's underground and to the sea.

Seawater Sample Contains Radioactive Iodine 1,150 x Maximum Allowable Level

The government's Nuclear and Industrial Safety Agency also said Monday radioactive iodine-131 at a concentration 1,150 times the maximum allowable level was detected Sunday in a seawater sample taken around 1.5 kilometers north of the drainage outlets of the troubled No. 1-4 reactors.

Hidehiko Nishiyama, a spokesman for the nuclear agency, said it is highly likely that the polluted water spotted near the No. 5-6 reactors flew from the sea area near the No. 1-4 reactors along the coastline.

Nishiyama said there were no health concerns so far because fishing would not be conducted in the evacuation-designated area within 20 kilometers of the plant and radioactive materials would be ''significantly diluted'' by the time they are consumed by marine species and then by people.

Removal of Highly Radioactive Water from Reactors Necessary

Removal of highly radioactive water in the Nos. 1-4 reactors at the Fukushima plant is necessary to reduce the risk of more workers being exposed to radioactive substances. The number of workers who have been exposed to radiation exceeding 100 millisieverts at the plant came to 19 as of Monday, the utility known as TEPCO said. Exposure to 100 millisieverts is the legal limit for nuclear plant workers dealing with an emergency, but the limit has been raised to 250 millisieverts during the ongoing crisis, the worst Japan has seen, at the plant some 220 kilometers northeast of Tokyo.

Among the 19, three received treatment at a radiation research center in Chiba Prefecture after they were exposed to radiation of 173 to 180 millisieverts Thursday. They were discharged Monday, with officials of the center saying the exposure has not affected their health.Since Sunday, TEPCO has been trying to move the radioactive water in the basement of the No. 1 reactor's turbine building to a tank in the unit by using three pumps. But the operator has yet to start such works at the remaining three reactor buildings due to difficulties in securing enough space at tanks to accommodate the polluted water, according to the nuclear agency.

Edano Cautions TEPCO About Under Estimating Radiation

Following TEPCO's correction of radioactive water analysis, which has undermined the credibility of the company's assessments, Edano as well as the nuclear safety agency cautioned the plant operator over its errors and instructed it to take necessary measures to avoid repeating such mistakes. Edano said at a news conference such errors ''can never be allowed'' as radiation measurement data ''serve as the major premises to ensure safety.'"

Government Spokesman Tells Evacuees Not to Return Home for Belongings

The top government spokesman also urged evacuees from the 20-km exclusion area around the plant not to temporarily return home to collect household belongings, citing ''great risks of radiation contamination'' in the zone. Earlier in the day, a strong earthquake with a preliminary magnitude of 6.5 jolted Miyagi Prefecture and its vicinity in northeastern Japan, but TEPCO said the quake was unlikely to affect work to restore the reactors' key cooling functions.

Radioactive material detected in air of 3 southern U.S. states

Trace amounts of radioactive material believed to have come from Japan's quake-hit Fukushima Daiichi nuclear power plant have been detected in the atmosphere in South Carolina, North Carolina and Florida, Reuters news service reported Monday, citing officials.

There is no current threat to public safety, the report said, quoting Drew Elliot, a spokesman for the power generation and distribution company Progress Energy Inc., which operates some of the power plants in the southern states.

Monitors at several nuclear plants in the three states picked up low levels of radioactive iodine-131, the report said.

''If there were radiation coming from one of our own sites, we would be seeing other types of radiation than iodine-131,'' Elliot was quoted as saying.

In the United States, radioactive materials believed to have come from the Fukushima nuclear plant have also been detected in several other states, including Hawaii, California, Nevada and Massachusetts.
Sources:

Radioactive Water Removal Underway; Fresh Seawater Pollution Found, Kyodo News, Tokyo, March 28, 2011

Radioactive Material Detected in Air of 3 Southern US States, Kyodo News, Tokyo, March 28, 2011