On January 30 the NRA, Japan's new nuclear regulator (not to be confused with the U.S. pro gun lobby, the National Rifle Association), released an initial draft outline safety rules for Japan's existing, largely shut down fleet of nuclear reactors. The detailed rule draft is expected in April, with final rules to be adopted by July 18, 2013.
According to press reports, the new rules will make it extremely time-consuming and expensive to restart reactors. The rules are to consider not only natural disasters, but also potential terrorist attacks.
Some highlights:
1. New cabling requirements. Apparently Japanese reactors approved before 1975 have cabling that would not meet the NRA's proposed requirements for flame-resistant coating. A complete recabling of these reactors is said to be prohibitively expensive, and if this rule becomes final, it might shut the door on any further efforts to restart older reactors.
2. Radiation filters. A new requirement that all have filtering vents that make it possible to discharge steam without releasing radioactive substances, to avoid the hydrogen explosions seen at Fukushima without releasing massive amounts of radiation into the surrounding area. Apparently this is less of an issue for pressurized water reactors (PWRs), which have much more substantial concrete containment domes, than for boiling water reactors (BWRs) such as those at Fukushima Daiichi. The Yomiuri reports that only two BWRs, at the TEPCO Kashiwazaki-Kariwa facility in Niigata, are expected to start work on installing these expensive filters in time for summer. The PWR reactors are said likely to be given a grace period for this requirement.
3. Higher seawalls. Seawalls must be high enough for the largest "hypothetically possible" tsunami. At the Hamaoka plant in Shizuoka -- number one suspect for tsunami damage, a new seawall has been under construction since 2011. Initial reports mentioned an 18 meter height. Now it is being built to 22 meters (72 feet) high, at a total cost of at least 150 billion yen (almost $2 billion).
4. Duplicate control rooms. The new rule outline requires construction of quake-proof crisis response building, including a second control room, that can take over plant operations in the event the main control room cannot be used because of quake damage, radiation release, terrorism, etc.
5. Additional earthquake fault data analysis. Finally, all plants are being required to undergo an additional, detailed survey to verify lack of any earthquake faults. As seen at Tsuruga and Higashidori recently, if the burden of proof shifts onto the utility to prove lack of earthquake faults, it becomes very hard to satisfy the requirement in Japan.
The lead story in Friday morning's Nikkei Shimbun suggested that the cost for satisfying these requirements is likely to be well over a trillion yen ($11 billion), and perhaps much more. A short English language summary of the Nikkei story is here.
Of course, both Hamaoka and Kashiwazaki-Kariwa are huge question marks in terms of seismic risk, so we could see hundreds of billions of yen spent at each location ... but neither ever restart. According to Nikkei, the most likely reactor restarts, in fall of 2013, are Kyushu Electric's Kawauchi reactor in Kagoshima, and Shikoku Electric's Ikata reactor in Ehime.
One English report from the Asahi Shimbun is online here.
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