In junior high I read Studs Terkel's Working, a collection of interviews with regular stiffs talking about their jobs. It made a deep impression on me. I was struck by how wrong many of my preconceived notions were. I remember the waitress who loved her job and was genuinely enthusiastic about providing good service to her customers. Where I expected the waitress to be bored and restless I found a dignified intelligent person enjoying her career. Then there was the jaded newspaper boy. Where I somehow envisioned the newspaper boy would be happy and greeted at every door with milk and cookies, I saw a cynic. My recollection is he did nothing but complain about the flinty people on his route who constantly tried to stiff him for the subscription.
With that, allow me to provide some insights about work at nuclear power plants. Depending on the feedback I'll do others, otherwise I won't waste your time and mine.
Story #1 - The Man With the Crapped Up Cash.
Last Thursday a worker was attempting to leave the Ft. Calhoun nuclear plant just north of Omaha when he set off the radiation portal monitor. When you work at a nuclear plant the last thing you do before exiting the turnstile is pass through a device that looks something like the metal detector you pass through at airports. It confirms you haven't inadvertently picked up contamination somewhere that you might track home. In this case the portal monitor went off, indicating the worker was "crapped up" somewhere. At this point the worker would have been gone over with a "frisker", analogous to the hand held metal detecting wands you see TSA wield. The problem was narrowed down to the worker's wallet and eventually isolated to three dollar bills. The money was likely then put in a germanium lithium-drifted (GeLi, pronounced "jelly") radiation detector to characterize the specific isotopes involved. It was Iodine-131. Make no mistake, I-131 is serious stuff. It is one of the primary fission products of concern in the event of a nuclear plant meltdown. It is responsible for most of the long term health effects from Chernobyl. Like ordinary Iodine, I-131 will make a bee line for your thyroid but unlike stable Iodine will hammer your thyroid with beta particles (basically energetic electrons) and gammas (like x-rays only stronger). Consequently some states stock potassium iodine (KI) tables to distribute to the public in the event of an accident. By taking KI you load up the thyroid with stable iodine so the body will reject the radioactive sort that falls out later.
But where did the I-131 come from in this case? Not that I-131 doesn't exist in nuclear plants but during normal operation most of it remains encased in the fuel and we only detect it in microscopic amounts. Moreover, nuclear plants go to great lengths to limit the areas that are contaminated and work hard to prevent workers from becoming contaminated when they do have to work in such areas. This individual performed no such work that day. Any why would the dollar bills be contaminated but not the worker's clothes or skin? Why just I-131 and not any of the other radionuclides you would expect to see as well?
The most likely answer is the worker unknowingly brought the contaminated money with him. You see, I-131 is also a commonly used medical isotope. When my sister developed Graves Disease years ago they dosed her with I-131 to pretty much destroy her dangerously overactive thyroid. She now takes synthetic hormones to compensate. But at the time of her treatment it was a big inconvenience. It took weeks for the I-131 to leave her system. In the mean time she was a walking radiation hazard. She was not allowed to sleep with her husband for a month so as not to expose him unnecessarily. She had to launder her clothes separately. She wasn't even supposed to hug her young nieces and nephews until it cleared out of her system. Ironically, she is an radiation tech at a hospital and was not allowed to return to work so as not to fog the x-ray film. Knowing my sister, I'm sure she followed her doctor's orders to the letter. But apparently not all patients are as cooperative. Most likely a recently treated patient paid for snacks at a convenience store (or something along those lines) and the unwitting worker followed behind and received some of the patient's contaminated bills as change. The worker didn't set off any alarms when he entered the plant because you only pass through the portal monitors when you leave, not when going in.
Story #2 – The Stripping Site Vice President
When I was a shift worker many moons ago at the Acme Nuclear Plant I would look for the vapor plume coming off the cooling towers on my drive to work. I could usually see it from miles away. The plume told me the direction the wind was blowing and how hard. More importantly (to me) if there was no plume it meant the plant had shut down. Sometimes the plume would rise to a point and flatten out as if hitting an invisible ceiling. On those days I would mentally check the clothing label on my shirt and slacks. Which brings me to the stripping site vice president...
I was talking to a female coworker the other day about a meeting she had with the site vice president at one of our plants. For our purposes, lets call him Mr. Burns. She arrived at his office at the agreed upon time and Mr. Burns showed up late wearing a shirt and tie and a disposable paper jumpsuit rolled down to the waist. "I lost my pants" grumbled Mr. Burns, stating the obvious to my surprised co-worker before taking a seat behind his desk and starting the meeting as if no other explanation was needed. None was (to someone who works at a nuclear plant).
The personnel portal monitors I mentioned in Story #1 are highly sensitive instruments. They are not set to alarm when they detect a lethal, or even dangerous level of radioactivity but at a level that is simply higher than normal background. They are calibrated to catch the unexpected.
You and I are surrounded by radiation every day from cosmic radiation and naturally occurring radioactivity from the ground. One of the primary sources of natural background radiation is Radon gas which is created as Uranium decays on its way to becoming Lead. Radon is everywhere. You are sucking in small amounts of it with every breath and Radon is believed to be the second leading cause of lung cancer in the US after smoking (a distant second). Normally when Radon seeps out of the ground it gets dispersed evenly into the atmosphere by the wind. But on days the leading edge of a warm front slides over the top of a cold front you have a temperature inversion and things like smog and Radon get held close to the ground. In addition, synthetic textiles tend to attract and hold Radon and its "decay daughters" more than cotton and other natural fibers. If you walk into a nuclear plant on a temperature inversion day when Radon concentrations are going to be high while wearing synthetic blends or if you forgot to use fabric softener to eliminate static cling you are taking a chance you will be going home in a paper jumpsuit. It has nothing to do with the plant itself.
Story #3 How to Turn Common Household Material Into Federally Regulated Radioactive Waste Without Trying.
Last September the San Onofre nuclear plant, which abuts Camp Pendleton in California, was notified by a local metal recycler that a shipment sent there by the plant had tripped its radiation monitors and that the truck was being returned to the site.
Let me explain some things. Like any home or business, a nuclear plant generates waste streams. Most plants I know have recycling programs like you probably have at your office. We have bins to recycle printer paper, plastic, used batteries, etc. The standard stuff. But we also generate waste in the working areas of the plant that is, or could be, radioactively contaminated. This waste is kept segregated from the "clean" waste like in the offices. The contaminated waste ranges from barely contaminated to waste that must be handled remotely. Not many facilities are licensed to take radwaste off our hands and they charge and arm and a leg so the industry goes out of its way to minimize it. You know those reusable grocery shopping bags you see in places like Whole Earth Foods? The nuclear industry has been using the concept for years. Any new parts to be installed in a radiation area are removed from their boxes and packaging and put into launderable bags to minimize the radwaste. If practical, an effort is made to decontaminate things like old metal parts, dollar bills and pants to below the federal limits to be "free released". Otherwise it becomes radwaste or if you are an activist or member of the press "dangerous radioactive waste". If you are the cynical type you might think there is a temptation to intentionally sneak contaminated waste in with the normal waste to save costs but that simply isn't the case. If caught there would be hell to pay from the public and politicians and the NRC would come down like flies on shit, not to mention jail time for those involved. Disposing of radwaste properly is expensive, but the cost of cheating would be way more expensive. It gets painful enough when plants make honest mistakes concerning waste shipments.
At San Onofre the source of the radioactivity turned out to be naturally high levels of Thorium in some left over ceramic floor tiles that had not even been brought inside the plant. Thorium is three times more abundant than Uranium, which itself is as abundant as Tin and Silver.
Which brings me to the concept of Naturally Occurring Radioactive Materials (NORM). Almost everything in nature is radioactive to some extent (including you) but obviously not everything is treated as radioactive waste. As a practical matter, the federal government exempts NORM from regulation. But that doesn't mean all NORM is lower in radioactivity than all radwaste. The granite used to build Grand Central Station and the US Capital building are so radioactive they would have to be treated as radwaste if they weren't NORM. The same for some high end granite kitchen countertops. The nuclear power industry and hospitals occasionally lobby to have the allowable levels increased to permit more waste to be sent to conventional landfills but this always generates a hue and cry in opposition. Frankly this issue isn't one of the reasons I take blood pressure medicine but there are those who feel strongly on both sides.
NEXT (if there is interest): "So the Site VP and I were standing in our underwear when the delegation of state legislators arrived..." and "The day I caught the Health Physics foreman pouring dog food down the toilet."