8.9 earthquake in Japan: tsunami warnings

I don’t know if this is a "rumor", but I heard on BBC that they lost normal power to cool the hot (but shoot down) core, and then tried to start the diesel reserve and that failed too, and now they are running the cooling system on batteries(?)... which will run out sooner or later...?

Today at approximately 2:46PM, turbines and reactors of Tokyo Electric
Power Company's Fukushima Daiichi Nuclear Power Station Unit 1 (Boiling
Water Reactor, rated output 460 Megawatts) and Units 2 and 3 (Boiling
Water Reactor, Rated Output 784 Megawatts) that had been operating at
rated power automatically shutdown due to the Miyagiken-oki Earthquake.

For the above 3 units, off-site power was lost due to malfunction of one
out of two off-site power systems, leading to automatic startup of
emergency diesel generators.

Subsequently, at 3:41PM, emergency diesel generators shutdown due to
malfunction resulting in the complete loss of alternating current for all
three units.

. . . .

Today at 2:46PM, turbines and reactors of Tokyo Electric Power Company's
Fukushima Daini Nuclear Power Station Units 1 to 4 (Boiling Water Reactor,
rated output 1,100 Megawatts) that had been operating at rated power
automatically shutdown due to the Miyagiken-oki Earthquake.

Currently, reactor water level for Units 1 to 4 is maintained by injecting
water into the reactors by the Reactor Core Isolation Cooling System.
The reactors are maintained at a subcritical condition.

For Unit 1, the emergency core cooling system automatically started up
due to increase in the reactor containment pressure assumed to be caused
by leakage of reactor coolant in the reactor containment.

Hence, at 5:35PM, it was decided that a specific incident stipulated in
Article 10, Clause 1 of the Act on Special Measures Concerning Nuclear
Emergency Preparedness *1 has occurred.

At 5:50PM, pursuant to the Act, relevant governmental institutions were
notified of the incident.

Future Actions: TEPCO is taking measures to reduce the pressure of the reactor containment.

Impact to safety and external environment:
Water level to cool the irradiated nuclear fuel in the reactor core is
maintained at this moment.
Indication of the monitoring posts installed in the periphery of the power
station is no different from usual and thus no radiation impact to the
external environment is confirmed at this moment.
We will continue to monitor in detail the possibility of discharge of
radioactive material from exhaust stacks and coolant water discharge canal.

. . . .

Here are the official statements from TEPCO. Any other statement from the media should be considered unsubstantiated.

Sheesh... that's amazing.

And thanks buddy.

Waves have already passed Hawaii, and they will hit coasts of Alaska, British Columbia, Washington, Oregon, California, and points south. Some of the energy will dissipate across the ocean.

An estimated 6.6-magnitude earthquake has struck Nagano and Niigata prefectures in Japan, Kyodo news service reports.

STORY HIGHLIGHTS
NEW: The U.S. is sending two disaster response teams to Japan
The quake is Japan's strongest in recorded history, Geologic Survey records show
The tsunami reaches as far as 6.2 miles inland
Hundreds of people are reported dead, with hundreds more missing

Japan warns of small radiation leak from quake-hit plant

P.S. Being a complete ignorant amateur – isn’t there very many large quakes "Near the east coast of Honshu, Japan" BEFORE the "BIG ONE"...???

8.9 336 megatons 1.41 EJ Sendai earthquake (Japan), 2011

The plant personnel apparently plan to release some pressure from the primary system, and they have to prepare the public for that. The steam would contain noble gases, radioisotopes of Xe and Kr, which would be vent up a stack and diluted in the wind, which will carry it eastward out to sea (Pacific Ocean). Ostensibly, any iodine will be captured on filters, which are designed to capture iodine, which is then allowed to decay.

Nevertheless, this is not a situation that any plant operator wants to be in. It is a black eye for TEPCO and Japans nuclear industry.

If this had been a pebble-bed reactor, would this have been an issue? Is there a reactor that would be able to avoid this kind of event?