Thursday, February 1, 2024

Diablo Canyon Nuclear Power Plant should be closed ASAP, NOT extended!

February 1, 2024

Dear Readers,

Today I spoke at a Nuclear Regulatory Commission (NRC) online webinar seeking public input regarding extending the license for the Diablo Canyon Nuclear Power Plant (DCNPP) another 20 years.

Various local government electeds insisted they were speaking on their own behalf, but all were in support of extending the license of the plant. Many highly qualified people spoke in opposition to the extension, a few insisted that Unit 1 should be closed immediately due to embrittlement issues.

At the high point there were a little over 100 people attending the online webinar including several dozen NRC employees, plus phone links. The meeting lasted over three hours: There were still about 70 people online when it ended, plus however many were on the telephone link.

Due to technical difficulties (Microsoft Teams isn't particularly user-friendly) a number of people were unable to speak (mostly microphones that could not be unmuted, but one pro-nuker had a serious problem with an "open" microphone). I was almost unable to unmute too, but at the last minute, 40+ years of prior personal computer experience saved me. (Truly the last minute: The host had tried various things for at least 10 minutes to unmute me, and there was only one more speaker after me, and the hearing was already running overtime!)

After introducing myself and stating that I was speaking for myself, and mentioning that I'm "nearing 70" and have had "two cancers and a stroke" I added that I too (like many of the pro-nukers who spoke) have "toured" a nuclear power plant, although I added that it was about 40 years ago, and was Connecticut Yankee, not Diablo Canyon. I described it as follows: "It was clean."

Then I explained that the rest of my remarks (shown below) were written while listening to the rest of the hearing today, and began to read what I had just written. About 2/3rds of the way through I offered to stop and submit the rest in writing, but the host kindly permitted me to finish. (I decided not to read the last two paragraphs anyway.)

For those living near the Diablo Canyon nuclear reactor, there will be a second NRC hearing next Thursday evening, in person, near the plant. Details are available at the NRC web site. I'm sure it will be crowded with plant workers who don't want their jobs to dry up and who have convinced themselves that low radiation doses are harmless, or even beneficial. (This is NOT the position of any official U.S. government agency, as far as I know. They all subscribe to the LNT (Linear, No Threshold) theory of radiation damage. The truth is much more complicated, of course, but LNT is probably a good approximation.)

Ace Hoffman
Carlsbad, California USA

P.S. I forgot to mention that both my cancers have been cured thanks to modern medicine, and the stroke, last year, was "mild." I'm basically in good health. Except for the hernia...well, and a few other things, but nothing life-threatening...except age...and an ongoing pandemic. Will the "public" hearing have high-energy UV air cleaners? HEPA filters (which were originally designed to filter...radioactive particles!)? Will they hand out N-95 masks at the door? Will they wear them themselves?


February 1, 2024
It is amazing to hear the pro-nukers try to justify the continued existence of nuclear power plants.

Forty years ago, they said we need nuclear power because of political turbulence in the Middle East. But America generally exports far more fossil fuels than it imports.

Thirty years ago, they said we need nuclear power because we were going to run out of fossil fuels, but more fossil fuels are  being pulled out of the ground than ever before.

Twenty years ago, they said we need nuclear power because wind and solar power "aren't there yet." But had we invested in them, they would have been there then.

Ten years ago, they finally -- FINALLY --  started to say we need nuclear power because of climate change -- an excuse with no more validity than any of the other excuses.

And now, they say [DCNPP] will save money while we switch to...something, but they assure us nothing is cheaper than electricity from nuclear power (meanwhile, it is, in fact, the world's most expensive energy). They say nuclear power is "baseload" because wind and solar are "intermittent" but ignore not only the sudden losses of such enormous amounts of power, but also the regular removal of this "baseload" power for required fuel replacement and rearrangement -- those outages might start at a scheduled time, but are often extended for unplanned lengths of time when unexpected problems are discovered during the inspections that always accompany the outages. Hardly reliable!

And [DCNPP's] emissions include not only regular radioactive emissions, but also significant fossil fuel use in the nuclear fuel cycle and during the operation of the reactor (several tens of megawatts of power come in to every reactor while it is operating, which are often generated with fossil fuels (and of course, the diesel generators burn fossil fuels if they're needed).

There are enormous risks of enormous emissions: ONE accident can release more nuclear effluents into the environment than all previous nuclear accidents in the United States to date. And there have been bad ones, but nothing like what is possible. Any time. Any day. Any reactor.

There is no reason to compare the emissions of Diablo Canyon Nuclear Power Plant with emissions of fossil fuels as an excuse to keep DCNPP open.

The question of emissions MUST include a calculation that includes the risk of accidents and their potential emissions. Because accidents do happen. They have happened, they are happening as we speak, and they will continue to happen.

Accidents have occurred at Three Mile Island, Chernobyl, Fukushima, Santa Susanna, SL-1, the loss of the Scorpion and the Thresher, lost bombs at Palomares, lost bombs off the coast of Georgia, and thousands of other nuclear accidents have already occurred around the world, each with global consequences.

The Nuclear Regulatory Commission's own oversight failures have caused huge financial losses and risked causing catastrophic accidents, such as when San Onofre Nuclear [Waste] Generating Station (near where I live) installed poorly designed replacement steam generators that the NRC let them consider "like-for-like" when they were substantially and significantly (and poorly) redesigned. The intent of the redesign was to increase profit for the power plant's owner, Southern California Edison. Instead it cost them billions of dollars and risked destroying all of Southern California.

In Ohio, multiple years of poor inspections on the part of the NRC resulted in a "hole in the head" of the nuclear reactor at Davis-Besse, a problem that was inevitably going to cause a meltdown -- the Reactor Pressure Vessel Head (RPVH) was completely rusted through, and the stainless steel liner was all that was holding back a meltdown -- and it was bulging out. The problem was discovered by a fortunate event: A worker leaned against a control rod during a fuel replacement, and the rod bent over!

DCNPP Unit One is KNOWN to be at severe risk of destruction from embrittlement, as has been mentioned several times in this hearing.

Clearly, the main purpose of extending the DCNPP license, either for the five years Pacific Gas and Electric claims they plan to extend the run of the plant, or for the 20, 40, or even 100 total years of operation that the NRC claims are possible for a nuclear power plant... is profit for the corporation. And kudos for Governor Gavin Newsom, a sly pronuker with an eye on the White House.

Diablo Canyon will be 40 years old soon. Other things that tend to fall apart after decades -- despite regular maintenance -- include buildings, pipelines, dams, computer centers, vehicles, ships...everything wears out.

And there isn't any reason to risk keeping DCNPP open anyway. Renewable energy includes widely distributed sources including, but not limited to, offshore wind, onshore wind, rooftop solar, industrial-level solar, geothermal, and so on. There is also a phenomenal opportunity within California for increased energy efficiency, which requires adding NO new energy sources. DCNPP could be closed just by increasing energy efficiency within the state.

Most importantly, after nearly a full century of being told that there is, will be, could be, or might be a solution to the problem of storing nuclear waste, even today we heard -- on the NRC's own hearing looking for comments from the public -- that we could simply rocket nuclear waste "to the sun" where it could harm no one. To call that preposterous, considering the accident rate of launches, hardly does it justice: Financially it's absurd too!

NRC thanked the person for his comments, which were strongly in support of keeping the DCNPP reactors open.

In reality there is no solution to the waste problem, and the nuclear waste from DCNPP will probably stay on site at DCNPP for centuries, if not forever. Nuclear waste is extremely hazardous -- millions of times more hazardous than nuclear fuel that has never been used in a nuclear reactor is. Yet making ever-more of this nuclear waste, without ANY solution to the waste problem, seems to be the only thing the NRC ever endorses.

The NRC could have already rejected PG&E's license application -- and ALL extensions to ALL nuclear power plant licenses -- because the NRC cannot guarantee safety to any reasonable degree of assurance. The NRC has no record to go on. There have been numerous accidents, releases, and near-misses over the years. Nuclear reactors -- let alone nuclear waste containers left out in the open -- are NOT protected against airplane strikes. They are not protected against numerous earthquake scenarios, tsunami scenarios, terrorism scenarios, operator error scenarios, intentional operator actions that can destroy the reactor...or common-mode failures where more than one or two things happen to go wrong at the same time.  It is well known that the NRC has not, and CANNOT,  evaluate such complex interactions of problems -- problems that can lead to catastrophe.

Lastly, continuing to operate the DCNPP actually BLOCKS clean energy solutions that do NOT produce millions of pounds of the most toxic substance on earth.

There is absolutely no safe and reasonable way to operate a nuclear power plant.

There are truly clean alternatives that are not based on burning fossil fuels.

Close DCNPP now. Don't wait until there is an accident, don't wait for the license to run out, and absolutely DO NOT extend the DCNPP license for a day, let alone for 20 years. The risks are too great and the alternatives are far cheaper, cleaner, more reliable (NOT LESS), and best of all: Safer.

Ace Hoffman
Carlsbad, California USA

The author, a computer programmer, has studied nuclear power and nuclear weapons independently for more than 50 years, including interviewing numerous scientists, and collecting over 500 books on nuclear topics.

Monday, September 18, 2023

Is AI useful in the nuclear industry? Maybe "yes" and definitely "no":

Is AI useful in the nuclear industry? Maybe "yes" and definitely "no"
by Ace Hoffman

September 18, 2023

First the good news: AI really is incredible.

Last week I heard a NASA spokesperson put it nicely. She said AI helps find "the data inside the noise;" the pattern "inside the wiggly line." AI is used to analyze long-timespan films of industrial machinery so that subtle movement that is causing stress cracking can be viewed. AI can help identify weakening parts, or identify long-term trends that are hard for humans to notice. Great stuff if it's used right. AI can be used to increase reliability of pumps and pipes in a sewage treatment plant. Sure, why not?

But will the same increase in reliability to pumps and valves in a nuclear reactor actually **prevent** meltdowns? Or just prevent SOME meltdowns? Well of course it's only "some" not "all." It's not a miracle drug. If it was THAT smart, it would tell humans to stop using nuclear power altogether!

Aside: We live in a world which is far more dangerous than it needs to be. Take air travel, for instance. AI is taking over all sorts of functions in the cockpit, including during dogfights of the world's top fighter jets. It's easing the mental strain on the pilots. It's even removing the pilots entirely. In fact, for 99% of all commercial flights, what do we need pilots for at all?

The answer, of course, is: Extreme or unusual situations. (Or a computer hardware malfunction, communications malfunction, equipment malfunction, software malfunction (besides the AI software itself), etc..)

But to be available when needed, the human pilots have to fly the planes themselves regularly, in order to be proficient when the "Scully" moment comes and you lose both engines flying out of a New York airport. Can AI help? Sure, but you know what would REALLY help? High speed rail. Far safer than air travel, ESPECIALLY for innocent bystanders when planes fall out of the sky. Nuclear power plants are NOT protected against large airplane strikes. And nuclear waste even less so. One of these days a terrible thing might happen. About a hundred large jets overfly San Onofre every day. Let's say the FAA manages to have AI software that alerts them instantly whenever a plane has been hijacked. Then how do they know if a nuclear power plant is being targeted? (Many hijacked planes have flown near nuclear reactors, of course, and at least one nuclear power facility has been threatened specifically (in the 1970s, if I recall correctly.)) But let's say the FAA decides to call a reactor and "warn" them that they "might" be targeted. What would a human operator do? What SHOULD they do? What would an AI program do? How easily can any FAA operator contact any nuclear reactor control room operator and what will they do with whatever knowledge has worked its way through the maze of steps, each of which could inhibit the warning going through, that results in whatever action is most appropriate? (SCRAM!).

We all use various forms of AI multiple times every day. And it helps tremendously.

But all that aside, one thing's for sure: Taking TWO things, neither of which works very well, and pairing them together is unlikely to yield a more positive result. Neither "nuclear" nor "AI" are properly functioning technologies (safe, reliable, etc.) -- and it's reasonable to assume that neither ever will be. Nuclear can NEVER be benign because it necessarily creates unmanageable waste streams and risks sudden catastrophic meltdowns; AI can never be benign because its mistakes can also cause real damage and, as described briefly below, it's "hit or miss" with no explanation of why it produces the results it gives.

(Further aside: During the Vietnam era the phrase "we had to destroy the town to save it" appeared. Perhaps AI will decide it has to cause a meltdown to prevent whatever it sees as otherwise unpreventable...)

I've always called "Artificial Intelligence" "Imitation Intelligence". I haven't changed my mind.

My wife and I have, together, more years in the computer industry than there are years in the computer industry (we started in our 20s, and are at 42 and 43 years the industry respectively; the industry isn't yet 85 years old (ENIAC was built late in WWII, less than 80 years ago).

Although neither of us have "officially" worked on AI development, we've certainly studied it, and we can make some qualified observations thus far, having worked near and around it since its inception. In my wife's current job, people use it frequently, for example, to write short code snippets or do research.

And our opinion of using it at nuclear power plants to help control the reactors? It's horrific!

The problem with AI is that AI returns a result we have no confirmation of (no "provenance"), and it is frequently wildly **not** what is needed or what will work in a particular situation. It's as if it forgot something obvious, you might say.

Modern chat AI, for example, simply grabs sources that seem related to the question asked of it based on criteria such as word count and word association, and assembles a response from those sources, with apparently little regard for the quality of the source. Humans try to ignore idiots. AI doesn't seem to know what an "idiot" is (perhaps because, in reality, it is one itself).

When returning results of a Google inquiry, usually no one really cares if it misses the 10th most-important web page on the subject and the person doing the inquiry doesn't find the information they desperately need, right? That sort of thing happens all the time -- you refine your query and try again.

But with AI running the show at a nuclear power plant -- controlling the valves, pumps, reading the temperature gauges and calculating the internal flow rates and instant-by-instant deciding whatever adjustments are needed -- well that might work fine for 100 years...and like FSD (Full Self Driving) it PROBABLY will be better at it than human control room operators.

But will it be perfect? Not likely.

Will it be "programmed" (or "taught") to know what to do when a meltdown starts? (Side note: If it's "really" AI it will throw its electronic hands up and say: "I CAN'T DO THIS!" and never even touch a nuclear power plant, they are simply too dangerous under ALL circumstances. But if humans aren't going to be that smart, can we expect AI to be?).

AI software is usually "trained" on vast amounts of existing data. Other AI can continue to "grow:" It can repeatedly go out on the Internet and get more current (but perhaps less accurate) data. Both are limited to what's available online at some time, not what's actually out there in the real world. A lot of past nuclear accidents are kept highly secret, either by the Nuclear Energy Institute, the Nuclear Regulatory Commission, or the owner/operator or even the employees involved. AI can't learn what it hasn't been exposed to. National borders block information exchange too, not just language barriers (which AI can -- sort of -- get around) but "proprietary" information and "NATSEC" information is intentionally hidden and unavailable. ("National Security" is regularly used as an excuse to hide reliability problems, embrittlement issues, operator errors, etc. that occur with military reactors.)

Besides all that, there's this: Will the AI software care if it fails and actually CAUSES a meltdown? NO. NOT AT ALL. And you can't punish an AI program for its failure, either. What are you going to do, turn it off and turn it on again?!? Tracking down the problem is well nigh impossible -- it's unlikely to be one line of code somewhere in the algorithm. AI's logic is, for all intents and purposes, encrypted -- and no one has the key. As a general rule: AI works in mysterious ways. That's kind of what makes it AI. The mathematical calculations are too complex for humans to comprehend. Its appeal is that it comes up with solutions humans have not been able to think of. It's awesome. But not perfect, and nuclear power needs to be impossibly close to perfection to be worth using.

My recommendation is we shut down the reactors. Thinking AI can be a "last best hope" to prevent operator error causing catastrophic (or expensive) accidents -- or merely improving efficiency -- isn't going to make them safe -- just safer (if we're lucky, and maybe not even that). AI won't eliminate "operator error," especially during critical, unusual or unique situations. It might even be the thing making the errors. And no one will know why it did what it did, possibly even in the aftermath.

Besides, nuclear energy actually blocks better solutions for Global Warming / Climate Change. Nukes suck up money and make false claims about being reliable "baseline" energy.

Keep AI where it belongs: Keeping cars on the road, and flying drones into ships and buildings...and into...nuclear power plants?!?

After the pilot has already bailed out?

(Also see substack clip shown below.)

Ace Hoffman
Carlsbad, CA
Professional computer programmer since 1980 (Assembler (LOTS of it!),
Cobol, RPG, Animate, HTML, etc. etc.)

Some programs I've written over the years (from: ):

"What is clear is that Cruise—and its main rival, Waymo—coucould do a
better job handling emergency situations like this. The memo about
Davis̢۪s deadly crash was one of dozens that Farivar obtained via an
open-records request and published online. These memos document at
least 68 times self-driving cars in San Francisco interfered with
first responders or otherwise behaved in ways that emergency workers
found disconcerting."
Source: Understanding AI <> 12:05 PM Sept 14 2023
Do driverless cars have a first responder problem?

Addendum (written/added Sept. 20, 2023):

After 9-11 there was a San Onofre annual safety meeting, and for the first and only time, there were PRESS galore. Cameras, reporters, everyone was there. Well over 100 people, when they were getting maybe half a dozen people at each NRC annual public meeting about the plant.

THAT DAY, before the meeting, mysteriously, I was surrounded by "enthusiastic" NRC personnel, about six of them -- all wanting to talk to me before the meeting. Wow! They're finally paying attention?!?!

I was so naive back then.

They were there specifically to keep me away from the reporters and news cameras.

Because I had blockbuster facts that our reactors are NOT designed to withstand large airplane strikes, and they knew I had the citations and would make some very devastating comments ON THE AIR that were all true, while the national tone was to pretend the reactors were safe.

After I wrote this latest piece, that F-35 went missing. An F-35 -- even unarmed -- can do quite a bit of damage to a reactor site, even if it's too small to breach the domes themselves. You really don't need to, though, to cause a meltdown.

The missing F-35 did cause me to make one change to the article I had already written -- I simply added the last line ("After the pilot has bailed out")!

Saturday, July 22, 2023

What's wrong with extending Diablo Canyon's license for one day, let alone 1826 additional days (five years)?

by Ace Hoffman
July 22, 2023

What's wrong with extending Diablo Canyon's license for one day, let alone 1826 additional days (five years)?


It's risking everything and gaining nothing. It gets in the way of progress and could be catastrophic. It wastes time, money and resources, and creates permanent problems future generations will have to deal with  -- even without an accidental release of radiation, the containers will still need to be maintained at least until a permanent solution is found -- and for hundreds of years AFTER that, since there is so much waste already which will have to be moved there. But where is there? Nowhere. No one wants the waste, and no one ever will.

We already have a state law in California which should have caused Diablo Canyon to close down years ago. The law forbids "new" nuclear reactors in California until and unless a solution to the waste problem is found -- outside of California. But decades later, mountains of nuclear waste remain on site with NO foreseeable solution.

Instead, California has had to make long-term arrangements to continue to store the used reactors -- the old reactor cores -- on site at each commercial reactor location.  Permanently. Billions of dollars has been spent storing existing waste in multiple locations around the state. The containments are thin-walled and in some cases are likely to be shoddily constructed. Holtec, for example, a major cask manufacturer and decommissioning corporation, has been cited repeatedly for various acts of negligence and non-compliance. So has PG&E.

None of it is safe from accidental airplane strikes or from terrorism (including using airplanes as weapons), or from war or social unrest, and much of it is also liable to be damaged (and released) in floods, tsunamis, earthquakes, or other natural phenomena. And don't discount asteroid impacts, either! An asteroid the size of the Empire State Building flew by earth (closer than the moon's orbit) just a few days ago!

These used reactor cores are called "spent fuel" but let's be honest: They ARE nuclear reactors! Nothing else makes a nuclear reactor a nuclear reactor! We could boil water in a pressure vessel a thousand different ways. We can turn turbines likewise! Wind, wave, flowing water...all collect energy safely from the environment and significant waste, and certainly nothing even a millionth as hazardous as nuclear spent fuel.

Nuclear reactors, on the other hand, are discarded regularly. They are only used ONCE, and then THROWN AWAY. But there is nowhere to "throw" them (long ago, so-called "experts" even considered launching nuclear waste into space (see my compendium of attempts at handling nuclear waste in the past, linked and included below)).

Reactors only last about 3 to 5 years. That's right! The reactor cores are "depleted" or "burned up" but they look the same, and weigh almost the same amount, and are still very much in existence. So it's NOT "fuel" or certainly just "fuel" -- it's the reactor itself!

Used reactors must be stored forever as highly toxic nuclear waste. By far the most toxic substance on earth! It wasn't very pleasant to begin with, but after being "used" it is somewhere between a million and ten million times more toxic, per pound. Or more precisely, per lethal milligram or microgram, and there are already millions of pounds of it. We don't need any more.

Nuclear power creates nuclear waste. The electricity it can provide for a fleeting moment is practically inconsequential compared to the problems created by the waste.

So why, if there is a law forbidding "new" nuclear reactors until the waste problem is solved (which can never happen completely) are the old reactors okay?

Because they were "grandfathered in." That's it. That's the only reason. And yet that was more than 40 years ago! Since then the OLD reactors have been RELICENSED once already -- and that contradicts the spirit and intent and, frankly, the meaning of the state law!

Besides, not only do we not need Diablo Canyon's power -- we've added many times that much, many times in the past -- but with clean energy alternatives (including "off-grid" alternatives that are becoming more and more commonplace). So have many other countries, and we -- and they -- are doing so now, and can do so easily again and again and again in the future -- not only do we not need Diablo Canyon, it IMPEDES clean alternatives!

For example, offshore wind in the Diablo Canyon area would be very easy to construct and could easily power the entire state. And the grid connections are already there! But Diablo Canyon is using them at the moment.

Offshore wind energy in that area could provide at least as many jobs as Diablo Canyon could provide, and if the goal is set soon enough, it would be replacing Diablo Canyon permanently very soon. We could have started yesterday. Instead we are wasting billions on the biggest risk to Californians in history: Two operating old nuclear reactors! Maintenance has been put off because they were expected to close: How many months (or years) of the five-year extension will they be inoperative for? One of them "needs" a new reactor pressure vessel: If that's NOT a "new" reactor, and the "fuel" assemblies are NOT a "new" reactor," then what IS a "new" reactor under the state law?!? And why was relicensing of these old behemoths NOT prohibited by the state law in the first place? (The answer to that is probably because the reactor companies assured the public that wouldn't be necessary since they were ONLY going to be used as an "interim" solution to cleaner forms of energy.)

Tens of thousands of people protested Diablo Canyon's being built -- for good reason.

Every day we wait to shut Diablo Canyon risks a Chernobyl or Fukushima (or another Santa Susana) right here in California. For what? To get in the way of renewables!

Shut it down. Shut it down today.

Ace Hoffman
Carlsbad, California

The author has studied nuclear issues for more than 50 years. He has a collection of over 600 books on nuclear topics and has spoken at several hundred public hearings including the CPUC, CEC, NRC, DOE and other local, state and federal agencies.


[Will add the full text of the above link to the final submission the CPUC]

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