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If there is not one single nuclear power plant in the world that was dsigned to resist the impact of a 747 at full speed and fuel-full loaded then you don't have to worry about earthquakes ...

I was wondering if Freepers had some good suggested book resources on Reactor Design or that plant in particular about its safety elements.

I don't know of any books to point you to. I went to college in SLO and I took one class that covered Diablo Canyon. We compared the construction of Diablo with Chernobyl's construction. It was built to withstand a 747 crashing into it. It was specifically built to withstand just about anything crashing into it. Hijacked planes were anticipated when they planned and built it. The rebar is supposed to be so thick that you can't get a finger into any space. In the event of any kind of problem with the reactor, it's designed to drop into a deep, concrete walled hole, and then more concrete goes on top of it. It's pretty safe.

Diablo Canyon would have a few more reactors if it hadn't been for special interest groups saying it was built on Native American land, or something like that. I don't remember that part specifically. It's been years and years since I took that class.

I did some of the design work for the reworking of the Diablo Canyon hydraulic snubbers. One reason why the plant sat completed but idle for about 10 years was because the kooks said the seismic safety analysis was inadequate. Current design basis earthquake requirements are that the plant safely shutdown for an earthquake equal in intensity to one twice that of the most severe earthquake ever experienced for the plant's geographic region. Diablo Canyon was redesigned to withstand one even stronger than that required by the rules, because of the actions of the intervenors. It was an unnecessary and costly change, and the ratepayers will pay a penalty all as a result of the wackos' ill-advised and unnecessary actions.

So the design basis earthquake for Diablo Canyon is one more than twice as powerful as the 1906 earthquake that wiped out San Francisco. In essence, you're talking about a plant that will survive a seismic event that would probably result in a good bit of California falling into the ocean. IOW, you're going to have other problems to worry about in that event, of much more consequence than anything that could happen to Diablo Canyon, which is the least of your worries at that point.

First off, according to the San Jose Mercury, Diablo Canyon did not trip and hummed along normally during the earthquake. I was somewhat surprised, since they do have accelerometers set up to trip the plant if it shakes hard enough. I guess it just didn't shake hard enough.

I worked there during the construction phase (it was ready for operation in 1976), and the "reconstruction" phase, where the plant had to be strengthened due to the discovery of an ancient fault line 3 miles offshore.

They had to go back and analyize every single pipe hangar in the plant - must have been millions of them. They added "whip restraints" to the main steam lines, in case one of them broke off (yeah, right...).

They beefed up the structure of the turbine building, and drilled 8" dia. holes through 100' of reinforced concrete to post-tension the turbine pedestal.

They welded studs onto the cooling water makeup tanks, then covered them with 8" of concrete.

BTW, I was there when they were still pouring the Unit 2 containment structure. Those big domes consist of 36" of reinforced concrete with a 3/16" welded steel liner. The reinforcing consists of six layers of 2 1/4" high-strength rebar, at 0, 45, 90, and 135 degrees. The sand in the concrete mix was quartz, not regular sand. Each batch was tested in the lab to make sure it reached proper ultimate strength.

As a final test, they pumped up the pressure in the massive buildings to 55PSIG and inspected every square inch to look for cracks.

Nothing short of an atomic bomb would so much as scratch that building.

But thanks to the Mothers for Peace (a bunch of burned out hippies left with no war to protest after Viet Nam ended), the operation of the plant was delayed for ten years at a cost to the ratepayers of billions.

IMO, no significant public safety was added by all these changes.

I lived in California during the construction of the Diablo Canyon plant. It seemed to me that there was quite a bit of concern that some systems (I believe) were built incorrectly (someone help me here, it's been a long time since I even thought about this). Nevertheless I don't think that would be a factor as to whether or not it could handle the impact of a 747. Earthquake, might be a problem though.