New aerial footage released by Tokyo Electric Power Co. (TEPCO) today details even more of the extensive damage to numerous reactors at the Fukushima Daiichi nuclear power plant following explosions at reactor Units 1 through 4 which occurred in the days following last weekend’s record earthquake and tsunami.
Early word so far today is that yesterday’s dangerous helicopter water drops onto Unit 3 have not succeeded in lowering the radiation levels at the crippled plant, as much of the water may have missed its target in the four drops. Radiation levels were so high that helicopter crews, outfitted in special protective gear, were forced to keep flying as they made their drops, rather than hovering over the No. 3 reactor.
As we reported yesterday, Japan’s Defense Minister said during a pres conference following the missions that, despite risks to both the fuel rods at the reactors and the safety of the helicopter crews that forced them to scrap plans for a similar drop the previous day, the severity of the situation had increased such that they “could not delay further.”
Water cannon trucks, normally used by Tokyo Police for crowd control, were dispatched to the plant after the air drops, but those efforts as well, reportedly, have been less than successful at lowering the temperature at the stricken nuclear reactors or the radiation levels at the plant itself.
As the UK’s Guardian reports today…
Six fire engines and a police water cannon were sent in on Thursday evening to spray the plant’s No 3 reactor. But afterwards radiation emissions rose from 3,700 microsieverts per hour to 4,000 per hour, the Kyodo news agency quoted Tokyo Electric Power (Tepco) as saying.
An earlier attempt in which military helicopters dropped thousands of litres of water on the plant also appeared to have failed.
We will continue our coverage of noteworthy developments in Japan’s nuclear crisis as warranted here at The BRAD BLOG, as well as via our Twitter account 24/7. You can follow us there at: @TheBradBlog.
Paul Gunter, Beyond Nuclear… talks about the situation in Japan
As I understand, each spent fuel pool measures 40x40x45 ft (length, width, depth). The fuel rods are located in the bottom 15 ft. Various sources recommend the tops of the fuel rods should be covered by at least 5 m of water (~16.5 ft). Starting with an empty pool, to barely cover the fuel would require up to 24,000 ft3 of water, i.e. 1,500,000 lbs of water, or 750 tons. Rounding down to allow space for the fuel bundles, let’s say 700 tons to fill spaces between the fuel. They dropped 64 tons of water onto reactor #3 and #4 via helicopter and water cannon. Hence with 30-40 tons dropped on reactor #3, most of which missed the target, the attempt naturally failed, and radiation levels continued to increase. To cover the fuel with 5 meters of water, would require a total of 1450 tons of water for each empty spent fuel pool.
In other words, darrch, they are
very, very desperate…