Jim Zim's pictures
A photo I shot of the Diablo Canyon nuclear power plant at dawn.
(Notice the goats grazing on the hillside!)
Greetings from California's central coast!
My name is Jim Zimmerlin (everyone calls me Jim Zim) and I worked for Pacific Gas & Electric Company at the Diablo Canyon nuclear power plant until my retirement in June of 2020. As all classic career tales do, my Diablo Canyon story began with working in the mailroom... and that was back in 1992. Let me tell you a little bit about my days at DCPP (Diablo Canyon Power Plant)... and share with you a few pictures I've taken over the years with several different digital cameras.
In case you're not already familiar with Diablo Canyon, let me just start by saying that the plant is built around two nuclear reactors which each produce 1,100 megawatts of electricity. All told, DCPP cranks out enough power for over three million people! The plant sits on a gorgeous stretch of the Pacific coast just west of San Luis Obispo, California. Because the plant site is off limits to the public, and shielded from view by a coastal mountain range, almost no one but the plant staff will ever see the Diablo Canyon facility. But as you continue a little further down the page, I'll show you what you're missing. I'm fairly confident that my view on the way to work in the morning is a lot better than yours!
But before I go any further, I'd just like to say that I worked at Diablo Canyon for a long time, in a lot of different roles that have given me a great look at how things work and how the plant is managed. Over all those years, I've never seen anything that led me to doubt the company's commitment to safe operation of the plant... and I've seen much that has impressed me. Diablo Canyon's outstanding track record is something that PG&E can be very proud of... and the people of San Luis Obispo county can certainly sleep well at night knowing that Diablo Canyon is operating safely.
In light of the crisis at the Fukushima nuclear plant in Japan, I'm sure a lot of people are skeptical about the idea of Diablo Canyon being safe. But once you understand the important differences between the Fukushima plant and Diablo Canyon, you'll see why what happened at Fukushima simply could not happen at DCPP. Let me explain...
Diablo Canyon has two major features that would totally prevent a Fukushima-style disaster from happening here. First off, the plant sits on a bluff that is 85 feet above the waterline. So, there’s absolutely no way that a tidal wave could wipe out Diablo Canyon's emergency cooling system. The decision to build the Fukushima plant at shore level is ultimately what doomed it. It survived the earthquake quite well, but the following tidal wave knocked out the emergency power source that could have pumped cooling water to the reactors. Diablo Canyon, sitting on a bluff 85 feet above the ocean, is simply not vulnerable to a tidal wave. Period.
The other thing (and this is the part that people really don’t seem to know about) is that Diablo Canyon has something that most nuclear power plants don't have… two gigantic reservoirs of freshwater sitting up ABOVE the plant on a hillside to the east. You can see them quite clearly in this aerial photo supplied by PG&E:
Because these water storage reservoirs sit up in the hillside above the plant, all it would take is opening a valve and gravity would do the rest… all the emergency cooling water you would ever need... and absolutely no electricity required. So, if the nearly impossible were to happen and Diablo should lose all electrical power including every one of the SIX emergency diesel generators… they could still cool down both spent fuel pools and both reactors with the water stored up on the hill. The whole problem at Fukushima resulted from the fact that they had no way to pump cooling water in to keep their reactor core cool. A Fukushima situation is simply impossible at Diablo Canyon.
I should also mention that the Diablo Canyon power plant has been built to withstand a much stronger earthquake than could possibly happen in our area. To put it simply, the plant was built with earthquakes in mind and has been engineered (with a large margin of safety) to not only handle the strongest possible quake that could occur on the nearest fault line... but to actually withstand simultaneous quakes on two different nearby fault lines!
When engineers talk about a structure's ability to withstand an earthquake, they talk about peak ground acceleration or PGA. PGA is measured in Galileo units... or usually just referred to as gal. A gal is defined as acceleration of 1 centimeter per second squared (1 cm/s²). The nuclear power plant at Fukushima was built to withstand an earthquake that could produce peak ground acceleration of 441 gal... but the earthquake in March of 2011 actually produced a PGA of 550 gal. Now let's see how California's nuclear power plants stack up to that. The San Onofre Nuclear Generating Station (near San Diego and Los Angeles) was built to withstand much stronger shaking than what was experienced at Fukushima. San Onofre was designed for PGA of 657 gal. And here at Diablo Canyon, we're sitting pretty... with an extremely robust design that can handle 735 gal of peak ground acceleration.
You also have to understand the concept of "margin of safety". Fukushima was designed to handle peak ground acceleration of 441 gal and actually withstood 550 gal quite well in the 2011 quake. (Keeping in mind that if there had not been a tidal wave after the quake, Fukushima would still be operating today.) So, when the engineers say that Diablo Canyon can handle 735 gal of peak ground acceleration, you can rest assured that there is a very large margin of safety built in to that calculation... and the reality is that the plant would be able to handle far more than that.
With that out of the way, let me tell you a bit about where I fit in at DCPP...
At the time of my retirement in 2020, my job title was "Administrative Specialist". There were about 40 of us at the plant in that job classification... and as the title implies, each of us have our own specialized niche. My job involved many different duties, but just about all of them involved the use of my hands. Maybe it shouldn't have been a big surprise when Carpal Tunnel Syndrome in both of my hands ended up being the thing that forced me in to retirement in June of 2020.
One thing that has really kept my PG&E career interesting is that I've been able to rotate in and out of different jobs over the years. Some of the job assignments have been more glamorous than others!
I already mentioned that my years with PG&E began in the mailroom... it was a great introduction to the company and a great way to meet employees throughout the plant. After that, I spent several years on a crew that performed hourly fire inspections throughout the plant. It took me in to the heart of the power plant, and gave me an amazing insider's view of all the little nooks and crannies of plant... everything from the control room down to all the obscure little electrical equipment rooms that even many of our most senior employees have never seen. In later years I had a great time working in the sign-making shop... was a "gopher" for the welding crew... worked the telephone switchboard... kept a document library up to date... and I even spent a little time on the "housekeeping" crew doing the real glamorous assignments (!) like emptying trash cans and picking up cigarette butts.
The most demanding assignment I ever had was during one of Diablo Canyon's refueling outages. I got to work on a team that actually goes inside one of the most radioactive parts of the plant... one of the primary steam generators. It's a big metal tank full of piping that converts hot water in to steam. During a refueling outage, the tank is drained of water, and someone must go in and install a metal cover to a pipe. The tank is so radioactive that no one is allowed to stay in it for more than four minutes.
My assignment was to go inside the tank and inspect the cover to make sure it had been installed correctly. Now I know that sounds easy, but believe me, it was not. I spent a week training in a mock-up so that I could learn to do the task as quickly as possible, thus minimizing the amount of radiation received. My part of the job involved two entries in to the steam generator... each about thirty seconds in duration. When the whole operation was over, I had received a dose equivalent to about 6 chest x-rays. Some of the other guys on the crew who spent almost the full four minutes inside got about five times as much radiation as I did... so I sure was lucky to have drawn the easier assignment.
So, why is it so difficult to go inside a steam generator and inspect a cover? For one thing, to get in to the steam generator, you have to squeeze through an opening only 16 inches wide! That's hard enough in itself, but imagine doing this dressed up in a big yellow plastic suit that prevents you from getting contaminated with radioactive particles... it looks kind of like an astronaut's suit... with an umbilical cord keeping you supplied with outside air so you breath uncontaminated air. The suit is called a bubble suit since it puffs up like a bubble from the pressure of the supplied air. The picture on your left is one of my co-workers in a bubble suit, during a training session. (Photo courtesy of PG&E)
Here's a funny story about that highly radioactive steam generator that I performed an internal inspection on...
Years after my little visit inside the steam generator, DCPP's steam generators started having some aging issues and needed to be replaced. It was a massive undertaking that took months of labor and cost hundreds of millions of dollars. During the project to remove and replace the steam generators, I happened to be out in the parking lot on the day that they rolled one of the old steam generators out on a massive transporter. As I was standing there, another employee hollered at me from across the parking lot to stand further back as the steam generator rolled by, because it was still somewhat radioactive. (The more distance you put between you and a radioactive source, the less radiation you will receive.) I laughed at the irony of being warned about getting too close to the steam generator... and felt like shouting back "hey, where were you when they asked me to jump inside that thing?!?"
So, that's a little look in to some of my job assignments at Diablo Canyon over the years. Perhaps you're wondering what was my favorite job of all. Well, believe it or not, it was actually that mailroom job that started my whole PG&E career off. More than any of the other jobs, it involved interaction with a lot of people... and the ability to give good customer service, which I'm pretty good at! So, a few years ago when I was given the opportunity to take the mailroom job again... I jumped at the chance. And I'll be the Diablo Canyon mailroom guy until I finally retire in September of 2020... 28 years after I started!
I've definitely seen a lot of changes at DCPP since I first started in 1992. One of the biggest changes involves how the company has trimmed staffing levels and insisted on getting things done with fewer employees. For example, back in 1992 we had two guys working together in the mailroom as a team... and these days it's just me. In fact, in 1992 we also had a a full-time person operating the reprographics machines in the room next door to the mailroom, and another full-time person maintaining our stock of office supplies in the storeroom behind the mailroom. These days, I do all three of those jobs... which in 1992 required four full-time staff! If you think I'm exaggerating... I assure you that I'm not! I definitely work harder now, and get less support than I did in 1992. Those were the golden days of PG&E... but the golden days never last forever, do they?
It's actually kind of funny how I ended up becoming the repro room guy in addition to being the mailroom guy. As I mentioned, the repro room is right next door to the mail room. One day a few years ago, the lady that ran the repro room had a week off work for vacation and they didn't have anyone to fill in for her... so I volunteered to handle her duties in addition to my normal duties for that one week while she was away. I knew it was going to be difficult to do the work of two full-time people... but I considered it a challenge to see if it was possible to do it by giving it every bit of energy I had. After all, it was only for a week, right? Well, my boss noticed that I was able to get both jobs done that week... and later that year when her boss told her that budget cuts required that we trim a position from our department, she figured that if I could do it for a week I could do it all the time. So, these days I'm a little more careful about how much extra work I volunteer for... because I realize now that temporary extraordinary efforts have a way of becoming the normal expectation!
On this page, you'll see many great photos that I've shot at Diablo Canyon over the years... but let me stress that I'm not a professional photographer, just the mailroom guy! I think it's pretty funny that a photo by the mailroom guy was placed on the wall of the office of the company President. In fact, that photo (at the top of this page) of the plant at dawn, with the goats grazing on the hillside, is probably the best photo I've ever taken at DCPP. It's certainly the one that people comment about the most, and it even made it on to the cover of an industry magazine. Not bad for an amateur!
You might be wondering if I got a ton of money from the magazine for the use of my photo.
I'm afraid not! And they even managed to misspell my name when they gave me credit for it!
In June of 2016, PG&E announced that they would NOT seek to re-license the Diablo Canyon power plant... and that they intend to shut down and decommission the plant at the end of the current licenses. (2024 for unit 1, and 2025 for unit 2.) This is bad news on several levels:
Thankfully, the plan to let DCPP's operating licenses expire won't have a negative impact on me and my family. I've been employed by PG&E since 1992 and my plan all along was to retire sometime around 2022 after 30 years of employment with the company and reaching the age of 65. So, when the announcement was made that 2025 would be the end of power operations at the plant, I knew that was plenty long enough to not jeopardize my family's financial situation. In fact, there's actually been a personal financial benefit from the situation. PG&E needs their experienced employees to stick around as long as possible, until the plant finally stops generating power. It's vital to avoid a situation where large numbers of employees bail out before the plant finally shuts down. So, it's in the company's best interests to offer financial incentives to employees who are willing to commit to sticking around during the final years of plant operation. That turned out to be a very good thing for me, at the tail end of my PG&E career. However, there are many employees at Diablo Canyon who are just at the beginnings of their careers. For them, the closure of Diablo Canyon in 2025 is definitely not good news.
All pictures are the copyrighted works of Jim Zimmerlin
(except as noted)
Wildflowers on the hillside next to the plant - May 2010
I shot this photo very early in the morning, just as the sun was rising
The unit 1 steam turbine and generator
I've waxed that floor before, and that's not a fun job!
A look at the power plant from the north
This is an angle that most people never see, since the area north of the plant is closed to visitors and even to most employees.
The coastline north of Diablo Canyon
Those hills are green in Winter and Spring, but brown in Summer and Fall.
This area would make one heck of a great state park someday after Diablo is eventually decommissioned.
April 2004 version of the Diablo Canyon wildflower photo
These flowers pop up each Spring, and I have made many attempts
over the years to get a good photo of the plant and the flowers
The coastline south of Diablo Canyon
The road to the plant lies on this stretch of the coast.
It makes for an incredibly beautiful commute to and from work each day!
1998 version of the Diablo Canyon wildflowers photo
This photo was actually taken with my very first digital camera... a whopping 1 megapixel camera.
Nowadays, I shoot with an 18 megapixel Canon Digital Rebel SLR camera.
The sun peeks through Oak trees
This beautiful grove of Oak trees is in the canyon behind the power plant.
This picture was honored as the "Digital Photo Of The Day" at a very
well respected photography web site on May 2'nd, 1999...
and again by another photography web site on August 7th, 2001!
A huge field of wildflowers just north of Diablo Canyon
PG&E owns a large amount of property surrounding the power plant.
For security reasons, there is no public access to this area...
so it is in pristine natural condition.
This picture was taken a mile or two north of the power plant.
Click on the picture to see a high resolution (3230x700 pixel) version of the photo.
Internet Explorer users: After downloading the large version of the photo,
Internet Explorer will most likely resize the big photo to fit your screen. To see the full sized version,
point your mouse to the lower right hand corner of the resized photo, and click on the "expand" button.
Let's talk about nuclear safety. The 1986 Chernobyl accident and the tsunami-related 2011 Japanese accident are certainly cause for concern. I'm sure you're probably thinking "Couldn't those kind of accidents happen at Diablo Canyon?"
Let's start with Chernobyl. You need to understand an important difference between American nuclear plant design and the design that the Soviets used. Nuclear reactors in the United States are enclosed in massive containment domes, the huge steel-reinforced cement structures that are so dominant in the pictures on this page. These structures would contain an accident within the dome. The Soviets were very arrogant and felt that their nuclear plants featured such superior engineering that there was no need for a containment structure... so the reactors at Chernobyl (and many others in the former Soviet Union) were NOT built within containment domes. When things went terribly wrong within the Chernobyl reactor, there was nothing to keep the radiation from spewing out in to the countryside. Only AFTER the accident was a containment structure hastily built at Chernobyl. (It is now referred to as "the Sarcophagus".)
One only needs to look to Three Mile Island to see the benefits of containment domes. The accidents at both Chernobyl and Three Mile Island were serious enough to permanently disable the reactors, yet at Three Mile Island the accident was contained because of the dome. The surrounding residents, while scared, suffered no health effects. Another critical difference between American and Soviet plant safety lies in the design of the reactor itself. The water moderated reactors in use today throughout the US are inherently much more stable than the design used at Chernobyl.
Besides containing any accidents inside the domes, the containment structures would also be excellent protection against a terrorist attack. An engineering study after the 2001 World Trade Center attack concluded that a fully loaded jetliner flown directly in to the containment structure of an American nuclear power plant would NOT penetrate the structure.
Speaking of security issues, let me assure you that for years now America's nuclear power plants have been prepared to defend against terrorist attacks. Security is not something that has been hastily added in the wake of the September 11th attacks... intense security is something that has been designed in to nuclear power plants since day one. I'm not going to discuss security issues any further here (heck, there could be terrorists reading this right now) but I would suggest if you are interested in reading more about the subject that you visit the web site of the Nuclear Energy Institute.
OK, what about the March 2011 nuclear accidents in Japan? That Japanese plant has a very similar design to some of the nuclear plants here in the USA... and they all had containment domes. But the big problem was how that plant was located at such a low elevation. When the tsunami hit, it rolled right over a seawall and knocked out every one of the Fukushima's emergency diesel electric generators. Without emergency power, plant operators couldn't operate pumps to direct cooling water to the reactors.
A tsunami of that intensity would cause very few problems at Diablo Canyon. Our plant sits on a bluff 85 feet above the Pacific Ocean... which means our diesel generators would be totally out of harms way should a tsunami strike. And just in case every one of our six emergency diesel electric generators fail and there's no way to run the electric pumps that normally circulate cooling water around the nuclear fuel... we've got two gigantic reservoirs of fresh water located on a hillside just behind the plant. Because they sit much higher than the plant, the water from these reservoirs can be moved by gravity alone. So if the unthinkable happens and we need emergency cooling water to flood over the fuel... it can be done by simply opening a valve. Gravity will do all the work. So even with all sources of electricity completely wiped out, it's pretty easy to get emergency cooling water flowing at DCPP. If they had been able to do that in Japan, Fukushima wouldn't be in the situation it's in now.
Sometimes people ask me if it is safe to work at a nuclear power plant. In December of 2000 I was diagnosed with Lymphoma, and some people have suggested that there must be a link between my job and the fact that I got cancer. While it's possible, I really doubt it. I wore a radiation monitoring device at Diablo Canyon at all times, so I know exactly how much radiation I received during the years prior to getting cancer. You might be surprised to know that I got more radiation exposure during the two CAT scans they performed in diagnosing my cancer then I did in all the years I worked at Diablo Canyon prior to that! And that includes the time I had to go in to that highly radioactive steam generator, as described earlier on this page. There are more than a million new cases of cancer in the USA every year... it just happens. Diablo Canyon probably had nothing to do with mine.
By the way, my cancer was successfully treated in the Spring of 2001 and I'm
perfectly fine now. It was an experience I won't ever forget, though! You can read about it and see some
funny pictures of me after losing my hair here.
Another thing people sometimes ask me about is the earthquake that rattled Diablo Canyon on December 22, 2003. The epicenter of this magnitude 6.5 quake was about 35 miles north of the plant. I was at home at the time of the quake, so I can't offer any first-hand reports, but I do have several friends who were at Diablo Canyon at the time. They say that there was very strong shaking at the plant site, but that the plant handled it well. It was not even necessary to reduce power or take the plant off-line... both units continued to run at full-power without a problem.
To understand how this was possible, while millions of dollars in damages occurred elsewhere in the county, you have to understand that Diablo Canyon was designed to handle a much stronger earthquake than this. Would it make you feel better to know that Diablo Canyon was designed and built to handle an earthquake that produces shaking twice as strong as the December 22nd quake? Well, I've got news for you... the truth is that Diablo Canyon was designed and built to handle shaking about TWENTY times as strong as this 6.5 magnitude quake produced! Certain politicians and anti-nuclear groups got all up in arms and called for an investigation of Diablo Canyon after the quake... I find that hilarious... and I think it just shows how out of touch they are with the truth about Diablo Canyon. This place has been engineered to the most demanding specifications. I've seen it up close, from the inside. You'd be hard pressed to find a safer place to ride out an earthquake than within the Diablo Canyon nuclear power plant!
Another important thing about Diablo Canyon that I'd like to mention is the economic aspect. There seem to be a lot of misconceptions about this! Some people have a perception that nuclear power is expensive... but in the case of Diablo Canyon, this couldn't be further from the truth. Did you know that Diablo Canyon provides power to California's electric grid at less than half the cost of the statewide average? The average cost of electricity produced in California is over 3.6 cents per killowatt/hour... but Diablo Canyon power costs less than 1.6 cents per kWh.
And let's not forget the economic benefits to the local area... in addition to employing over 1,400 people at the plant itself, the economic activity generated by Diablo Canyon accounts for well over 500 other full time jobs in San Luis Obispo county. A study by the Nuclear Energy Institute recently concluded that Diablo Canyon's contribution to the California economy was over over a billion dollars every year! Look nationwide and Diablo Canyon's impact is almost two billion dollars every year.
And there's one other "hot topic" I'd like to mention, and that's the once-through-cooling system that is used at the plant. DCPP is situated next to the Pacific ocean for a very good reason: a gigantic supply of cold seawater provides a very simple and inexpensive way to provide cooling for the condensers in the non-nuclear side of the plant.
There's been a lot of talk about forcing PG&E to abandon the existing
once-through-cooling system. The people behind this idea have argued that using massive amounts of ocean
water ends up killing large amounts of marine life. I think they want you to believe that the plant sucks up fish
and crabs and seals and things like that. But when they talk about ocean creatures getting sucked in to our
cooling system... what they're talking about is fish larvae. Larvae! We're talking about things a few
millimeters long. If you know anything about marine biology, you know that fish lay huge amounts of eggs and that
in a tiny section of the ocean there can be huge numbers of larvae. So, yes, when you add up the numbers of how
many larvae are sucked up in to our cooling system over a long period of time... you can make the numbers sound
pretty big. But it's just larvae, and it's an insignificant tiny fraction of the overall population. Even if
Diablo Canyon didn't use ocean water for cooling, about 98% of those larvae wouldn't reach adulthood anyway.
That's why fish lay so many eggs! Let's say they modified the plant to eliminate the once-through-cooling system.
Huge numbers of fish larvae would be saved... and how many of them would grow up to be adult fish? About 50
a day. And to achieve this addition of 50 fish per day to the Pacific Ocean would cost how much to make the
modifications to the plant? Somewhere in the vicinity of $2,000,000,000 - $4,000,000,000, and it would all have to
be paid for by PG&E's customers in the form of a rate increase. Do the math and divide it out and see how much it
works out to... per adult fish saved. It's an absolutely CRAZY idea that makes no sense at all.
The power plant is surrounded by a large buffer zone of several hundred acres. The buffer zone is in pristine condition and hasn't changed much from the days when native Americans lived here. Public access to this part of the coastline is extremely limited, and the land is used mainly for livestock grazing. Here are a few photos from PG&E's property surrounding the Diablo Canyon site...
An April 2007 photo from the area north of the power plant
Just a little bit north of the previous photo, I put the camera on a tripod so I could be in this shot
A March 2007 photo from the other (south) side of the power plant, looking north
The Point San Luis lighthouse sits on the far south end of the Diablo Canyon buffer zone.
Click here to see some pretty photos I took on a hike to the lighthouse in 2003
How about a few more pictures?
Visit the Jim Zim photo gallery, featuring more pictures I've taken throughout San Luis Obispo county
Public tours of Diablo Canyon were discontinued after the 9/11 terrorist attacks. However, PG&E does have a facility in San Luis Obispo called the Energy Education Center… which features exhibits about a variety of PG&E interests including the Diablo Canyon power plant. If you're interested in Diablo Canyon and you happen to be in our area, I would definitely suggest stopping by the E.E.C. for a look at the exhibits. The address is 6588 Ontario Road in San Luis Obispo… which is just off the 101 freeway at the San Luis Bay Drive exit. Click here to see it on Google maps. Click here to read a little more about the E.E.C., including their operating hours and phone number.
All pictures on this page have been reviewed by DCPP security, and have been cleared for display on this site.
If you'd like to see more pictures of the San Luis Obispo county area
that I've taken with my digital camera, please visit my SLO pictures page.
Please note that this is an unofficial Diablo Canyon web site.
To read a fascinating article
about the nuclear power industry,
which discusses the important role that nuclear plays in our nation's energy mix
and also covers reactor safety, the storage of nuclear waste, and how nuclear power
plays an important role in the fight against global warming click here.
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