Philippine waters safe – PNRI

source: mb.com.ph

MANILA, Philippines – Philippine waters and the marine life within its bounds remain safe even if radioactivity finds its way into the country through sea currents from Japan, in the wake of the release of tons of low-level radioactive water from the earthquake-damaged Fukushima Dai-ichi Nuclear Power Plant, the Philippine Nuclear Research Institute (PNRI) assured Thursday.



PNRI’s assurance was contained in its information bulletin No. 20, which it issued after it was reported that the power plant had already started releasing tons of low-level contaminated water into the Pacific Ocean.

“The DoST-PNRI does not expect that the Philippine waters will be threatened by the discharge of radiation contaminated water from the Fukushima plant,” the PNRI bulletin said.

It added that the water contaminants from Japan sea water – Cesium and Iodine – are soluble in water.

“The Pacific Ocean is so vast with its sheer volume and depth that the radioactive contaminants will be very much diluted and will not pose harm to the Philippine public and marine organisms,” the PNRI said.

It noted that following the modeling of the dispersion of radioactive isotopes in the ocean, which has been initiated by the SIROCCO group of the Observatoire Midi-Pyrenees, University of Toulouse in France, the Philippines is assured that once water current reaches it, “the concentration of radioactive isotopes will be negligible.”

The PNRI said that to ensure the safety of the country’s marine environment and the public, it would continuously perform radiological surveillance activities, which include collection, monitoring, and analyses of our marine biota for radioactivity.

In a radio interview, PNRI senior science research specialist Marvie Palattao said even people living in Batanes, the northernmost island of the Philippines nearest the Japanese coast, have nothing to worry as far as eating seafood is concerned.

This, he said, because the contaminants’ dosage of radiation, in the event that it gets into the country from Japan, would just be equivalent to that of a single banana.

Pallatao noted that the dosage of the released radioactive water would already be safe to human once it travels 30 kilometers off the releasing site.

“Thirty kilometers away from the location of released radioactive material (would) already (be) safe” he said.

Per the estimate given by Tokyo Electric Power Co. (TEPCO), the annual dose of radiation the contaminants could add to an individual would just be around 0.6 millisievert, should he eat seaweed and seafood caught near the plant, daily.

Preventing nuclear blasts

Meanwhile, workers at Japan's flooded nuclear power complex turned to their next task Thursday: injecting nitrogen to prevent more hydrogen explosions after notching a rare victory by stopping highly radioactive water from flowing into the Pacific.

Nuclear officials said Wednesday there was no immediate threat of explosions like the three that rocked the Fukushima Dai-ichi plant not long after a massive tsunami hit on March 11, but their plans are a reminder of how much work remains to stabilize the complex.

Workers are racing to cool down the plant's reactors, which have been overheating since power was knocked out by the 9.0-magnitude earthquake and tsunami that killed as many as 25,000 people and destroyed hundreds of miles (kilometers) of coastline.

Unable to restore normal cooling systems because water has damaged them and radioactivity has made conditions dangerous, workers have resorted to pumping water into the reactors and letting it gush wherever it can.

Superheated or damaged fuel rods can pull explosive hydrogen from the cooling water. If the gas were to combine with oxygen, there could be a blast, but nitrogen reduces that possibility.

Technicians began pumping nitrogen into an area around one of the plant's six reactors early Thursday, said Makoto Watanabe, a spokesman for Japan's Nuclear and Industrial Safety Agency. They want to prevent hydrogen explosions that could spew radiation and damage the reactors.

An internal report from March 26 by the US Nuclear Regulatory Commission warned such explosions could occur.

The nitrogen pumping also has risks, but Japan's nuclear agency approved it as a necessary measure to avoid danger, spokesman Hidehiko Nishiyama said. The injection will take six days and could release radioactive vapor into the environment, but residents within 12 miles (20 kilometers) of the plant have been evacuated.

The government said Wednesday it might consider expanding that zone, though not because of the nitrogen injection. An expansion might not necessarily mean the radiation that has been spewing into the air and water from the plant is getting worse. The effects of radiation are determined by both the strength of the dose and the length of exposure, so the concern is that people farther away might start being affected as the crisis drags on.

“I would imagine residents in areas facing a possibility of long-term exposure are extremely worried,” Chief Cabinet Secretary Yukio Edano said. “We are currently consulting with experts so that we can come up with a clear safety standard.”

Edano did not say how far the zone might be expanded or how many people might be affected. Tens of thousands have been living in shelters since the tsunami, either because they lost their homes or are in the evacuation zone or both.

Police in hard-hit Fukushima prefecture prepared to launch a full-scale search for bodies in the evacuation zone Thursday. Nearly 250 agents from the Tokyo Metropolitan Police will join local police searching for 4,200 people still missing there.

Meanwhile, the US State Department confirmed the death of Montgomery Dickson, the second American confirmed killed in the disaster. It gave no other details.

At the plant, 140 miles (220 kilometers) northeast of Tokyo, workers finally halted a leak of highly contaminated water that raised worry about the safety of seafood caught off the coast.

But even that rare good news came with a caveat. Highly contaminated water pooling around the plant has often made it difficult or impossible for workers to access some areas because of concerns about radiation exposure. Now that the leak has stopped, the pooling could actually get worse because water that had been going into the ocean could back up onto the grounds of the complex.

And the confidential NRC assessment – obtained Wednesday by The Associated Press – noted that plant operator Tokyo Electric Power Co. still faces several challenges. It said that salt from seawater that had been used as a coolant is probably blocking circulation pathways, particularly in reactor 1.

source: mb.com.ph