Home Interviews THMG124 – SL-1 Radiation Fatalities with Gail Carter

THMG124 – SL-1 Radiation Fatalities with Gail Carter


In this episode, Bob and Mike talk to hazmat specialist Gail Carter about the first and only nuclear radiation fatalities in the United States. He wrote an article on the subject called Atomic Firefighters: Lessons from the SL-1 Accident for Today’s Responders, which we link to in the show notes.

Complete Show Notes

1:00 Introduction to Gail Carter

  • Currently a hazmat specialist and driver engineer with the City of Santa Clara Fire Department – he’s worked here for 6 years
  • They’re a mid-size all hazards agency in the south San Francisco Bay Area close to San Jose and the Silicon Valley
  • Prior to this job, he worked in the private sector with power generation for 10 years
  • Also had a brief stint at a nuclear facility in the Midwest
  • Graduated from the Naval Nuclear Power program and was an enlisted mechanic and radiation specialist onboard a nuclear submarine at Pearl Harbor
  • Also trained as a chemistry technician and a radiation control technician

6:45 Why Gail Wrote This Article

  • Article is called Atomic Firefighters: Lessons from the SL-1 Accident for Today’s Responders and was published in two parts:
  • Gail sought to combine his fire service hazmat experience with his nuclear experience
  • He’s also a military history buff and learned about this incident during his training
  • Story has been sensationalized over the years and turned into a cautionary tale, so he wanted to set the record straight
  • This incident was one of the first nuclear disasters where the fire department played a big role in response

10:00 Background of the SL-1 Accident

  • SL-1 stands for stationary, low power, first design
  • There was a friendly rivalry between the 3 branches of the military back in the Cold War years for government funding
  • After nuclear power was developed, scientists and organizations began looking at the atom as an unlimited source of power
  • The Navy developed a nuclear submarine and the Air Force developed a nuclear bomber, but the Army didn’t have anything nuclear powered
  • Developed nuclear powered Distant Early Warning (DEW) lines designed to spot any threats that came over the poles
  • Created the National Reactor Testing Station in the Idaho desert – conducted a lot of experiments to figure out how far we could push nuclear power
  • The Navy, Air Force, and Army went out there and worked on building nuclear prototypes alongside civilian workers – prototype for USS Nautilus was built there

17:05 The SL-1’s Main Failure Point

  • There have been a lot of sensationalized stories out there – caused by a love triangle, murder/suicide, etc.
  • This reactor had one main central control rod that regulated the generation of neutrons – this is a sub-critical part
  • Acts like a throttle or gas pedal – controls how many neutrons are available to fission the fuel inside the fuel plates
  • In most cases, you wouldn’t have one huge fuel rod that would catastrophically destroy the reactor when removed – the SL-1 did because they wanted simplicity and wanted to keep the crew as small as possible
  • There was no boron to inhibit a polymerization reaction, which meant they could continue pushing the reactor to its limit
  • Happened during a routine maintenance shutdown over the holidays – scheduled to bring it back up on January 4, 1961 but the accident happened on January 3
  • During maintenance, they had to lift the central control rod out of the reactor and re-engage it with its drive mechanism (like a motor and rack and pinion assembly)
  • For whatever reason, the rod was pulled out past its critical point and out of the reactor – led to the amount of power increasing exponentially in a short period of time
  • The nuclear reactor couldn’t handle this increase and was overloaded – overheated and caused a steam explosion
  • Materials in the reactor reacted with the steam and made hydrogen – continued to feed off of itself – this was a single circuit boiling water reactor, which made things even worse

23:55 Initial Response of the Fire Department

  • The local fire department had been out to the SL-1 site several times that day in response to false alarms – the overhead heat detector in one of the furnace rooms kept going off
  • A group of 6-7 firefighters were on duty when they received the alert at 9:01 PM on the evening of the 3rd – remember that there was nobody else there for them to communicate with
  • As they went through the guard house, the portal contamination monitor was going off – this indicated that there were high levels of airborne radiation present
  • Firefighters had very little training in radiological response, which was also problematic
  • The structure the reactor was housed in was not designed to be a containment building – there was probably some shine coming from the reactor room

29:25 Moving Further Into the Complex Towards the Reactor

  • Saw a flashing high radiation light going off on the control panel in the deserted control room
  • At this point, they realized something wasn’t right and went back to the rig for a survey instrument
  • The needle took off on their meter and went straight to the right side – old, analog dial only went up to 5 R per hour, so they couldn’t tell exactly how over range they were
  • Went outside and got a second instrument to confirm the results of their first instrument – second instrument confirmed the first reading
  • They went back out to the parking lot and activated the general alarm for the site – this informed the civilian contractors, military chain of supervision, and experts on radiation and health that something was very wrong at SL-1
  • As they moved further up the spiral staircase towards the reactor, the experts took over and the firefighters served as backup
  • Fire chief had the rest of the firefighters stay down at the control area in the parking lot to keep them safe

36:30 Reaching the Reactor

  • When they make it to the top of the stairs, they can immediately tell the reactor is completely destroyed
  • The health physics technicians have started to arrive on-site and enter the facility
  • Punched metal supports were blown all over the place and the lights were out
  • The area was steamy since there was a steam explosion
  • Found one of the crew members motionless who had clearly experienced massive trauma
  • Another crew member was barely clinging to life on the reactor room floor – took this viable victim to the parking lot and started to treat him – he was already highly contaminated and had fuel particles embedded within his body
  • They couldn’t find the third crew member
  • Health physics technicians started recommending stay times to keep responders safe – recognized the danger of airborne radiation at this point
  • Put everyone on air at this point because they didn’t want to get alpha and beta rays inside their respiratory tract
  • Viable victim died by the time the ambulance made it to the first checkpoint – they left him by the road before the checkpoint because he was already giving off so much radiation and endangering other people
  • They continued to make subsequent entries to find the third person and saw a wet bundle of rags hanging from overhead in the control area
  • Shield plugs blew out of the reactor when it exploded, impaled the third operator, and blew him up into the overhead and superstructure – he was killed instantly
  • The second technician was killed because he was blown into concrete blocks they had moved in order to power up the reactor

45:10 Lessons Learned

  • All of the techniques and tools used by the responding firefighters can be scaled and applied today
  • Never assume that something this catastrophic can’t happen where you live
  • We’re focused on terrorist attacks and biological warfare agents, but you have to think about these types of incidents, too

48:40 How to Contact Gail

  • LinkedIn: Gail Carter
  • Civilian email address: Gail Carter

Have a question? Send an email to feedback@thehazmatguys.com or leave a message on our Haz Mat Guys comment hotline: 843-628-1484

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  1. Hi Gail,

    Very interesting and informative read.

    Do we know what happened to the firefighters that answered the call that day?

    They were exposed to high levels of radiation, did this cause any health problems after the incident?

    • Hey Morgan,

      We here at The Haz Mat Guys are unsure to the answer to this question. We will reach out to Gail to ask for some answers.


  2. Morgan –

    Thank you very much for listening to the podcast and reading the articles!

    Did their rescue work that night affect the rest of their lives? Without access to exposure and medical records, which of course are protected personal health information, we can’t be 100% certain. However, most of the SL-1 firefighters anecdotally appear to have lived to an age that is considered to be a normal (read: reasonable) human lifespan.

    Egon Lamprecht, the “young, good-looking Mormon kid” who wanted to make good money as an Atomic Firefighter passed away in 2014 at the age of 79. Judging by how spry he was in many of the video interviews and lectures he gave on the Sl-1 accident well into his later years, there is no reason to suspect that this was from anything other than natural causes. His obituary can be found here: https://www.legacy.com/obituaries/postregister/obituary.aspx?pid=173252677

    Egon was the youngest of the firefighters that responded in that night at the age of 25. He was also later perhaps the most well-known as he was interviewed many times for both print and video media regarding the accident. You can see him on many documentaries done in later years, including the one that was done for the History Channel’s “Modern Marvels: Engineering Disasters” series. He clearly endeavored to keep the memory of what they walked into alive, passing it on to the next generation of nuclear workers and first responders.

    Mel Hess was still alive as of November 2014 when he gave an interview to the Idaho Falls Post Register regarding the response to the accident, possibly around the same time as the death of his fellow firefighter Egon Lamprecht. That article can be found online, but unfortunately the Post Register now requires an account sign-up to view their online content. Although I am sure it is very exciting reading, I’m not interested enough in the day-to-day goings-on in Eastern Idaho (no offense!) to sign up. https://www.postregister.com/

    The other firefighters kept much lower profiles. A cursory search of the internet only reveals one possible match out of that entire first-due engine company roster from that responded to the SL-1 accident.

    Vern Conlin, possibly present that fateful night in 1961, passed in 2017 at the age of 82. I say “possibly” because it is not absolutely confirmed. However, the timeline adds up, his name is on the duty roster, and he retired as a Fire Captain after a 30 year career at INL. That’d all have to be a pretty big coincidence. His obituary can be viewed here: https://www.legacy.com/obituaries/postregister/obituary.aspx?pid=185840537

    It would probably take another series of articles and a follow-on podcast : ) to adequately get into the health physics particulars regarding the dose these men received based on their particular job tasks and positions that night. Then we’d have to look at that acute exposure against the bigger picture of the dose they received over their entire lifetime. We’d probably eventually get into acute vs. chronic effects of radiation exposure, dose vs. benefit (ALARA), Linear-No-Threshold (LNT) Theory, etc. etc. etc. Several books out there by individuals much more learn-ed and accomplished than myself can better-explain these relationships, including how the odds shake out regarding deterministic (sterility, cataracts, erythema) vs. stochastic effects (radiogenic cancers, genetic effects). Remember that on a long enough timeline, we ALL will get cancer. Might I suggest this excellent book as a source for further reading on the topic, I have it on my own shelf at home (“Strange Glow: The Story of Radiation” by Professor Timothy Jorgensen, Georgetown University. Bonus: the dust jacket glows in the dark!): https://press.princeton.edu/titles/10691.html

    Some well-done presentations by industry folks I’ve received in response to the original articles ballpark the exposure levels on the SL-1 reactor floor immediately following the incident at 500 – 1000 R/hr. But, you must remember that by then the firefighters were thankfully operating with site health physics techs directly supporting them, and stay times were tightly controlled at 1 to 3 minutes. A responder who stayed at the top of the stairs for 3 minutes in a 500 R/hr field to survey the scene and plan a rescue/recovery would take a calculated hit of 25 R (the currently recognized EPA limit for lifesaving). Remember that this limit used to be 100 R back in the day, and was probably tightened down in large part due to the experience from SL-1! The stretcher bearers who ran into the reactor room could have been exposed to a 1,000 R/hr radiation field worst-case and thusly would have taken a hit of 100 R in 6 minutes if my Sunday afternoon firehouse math is correct. However, they were administratively limited to 1 minute shifts as a turnback limit for safety’s sake.

    The one eventual death that may be directly attributable to internal radiation exposure during the accident could be that of Ed Vallerio, who passed of cancer in 1999. Recall he was the health physics technician who had to remove his SCBA mask and take a few breaths while still in an environment that contained material emitting particulate radiation (Alphas, Betas). As related in the book “Idaho Falls: The Untold Story of America’s First Nuclear Accident” by William Mckeown, Vallerio had been carrying one of the injured soldiers when his SCBA failed. He reportedly did a quick mental risk/benefit calculation of the internal committed dose he would received by doffing his mask and attempting to hold his breath, and determined it was worth it. Supposedly, his companion HP Paul Duckworth had to do the same, but a search yields no results on his fate.

    I sincerely hope all this answers your question. Thanks again, and stay safe!


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