US and Japanese experts have suggested that radioactive releases of steam from the crippled nuclear plants in the aftermath of an earthquake-cum-tsunami in Japan could go on for weeks or even months.
The also said that the country faces a wide range of problems ahead.
The emergency flooding of two stricken reactors with seawater and the resulting steam releases are a desperate step intended to avoid a much bigger problem, which is to avoid a full meltdown of the nuclear cores in two reactors at the Fukushima Daiichi Nuclear Power Station, The New York Times reports.
On Monday, an explosion blew the roof off the second reactor at Fukushima. Officials say that although it did not damage the core, it apparently leaked more radiation.
Japanese officials have been saying so far that the melting of the nuclear cores in the two plants is assumed to be "partial," and the amount of radioactivity measured outside the plants, though twice the level Japan considers safe, has been relatively modest.
Pentagon officials, however, have claimed that helicopters flying 60 miles from the plant picked up small amounts of radioactive particulates, which are yet to be analysed. But it is presumed to include cesium-137 and iodine-121, suggesting widening environmental contamination.
Following a series of intense interchanges between Tokyo and Washington over the weekend, and the arrival of the first American nuclear experts in Japan, officials have said that they were beginning to get a clearer picture of what went wrong over the past three days. One senior official even went to the extent of saying that: "Under the best scenarios, this isn't going to end anytime soon."
The paper quoted Christopher D. Wilson, a reactor operator and later a manager at Exelon's Oyster Creek plant, near Toms River, New Jersey, as saying that "normally you would just re-establish electricity supply, from the on-site diesel generator or a portable one." Portable generators have been brought into Fukushima, he said.
He also said that Fukushima was designed by General Electric, as Oyster Creek, was around the same time, and the two plants are similar. He also said the problem was that the hookup is done through electric switching equipment that is in a basement room flooded by the tsunami, adding: "Even though you have generators on site, you have to get the water out of the basement."
Another nuclear engineer with long experience in reactors of this type, who now works for a government agency, said "To completely stop venting, they're going to have to put some sort of equipment back in service." (ANI)