NukeWorker Forum
Career Path => Radiation Safety => Topic started by: S T I G on Jan 10, 2014, 05:53
-
1) What is the worst radiological screw up you have ever witnessed on the job?
2) What did you learn, if anything?
(try and keep it fairly short if you can)
-
death,...
Damn... beat me by a minute
-
I slightly altered the question..
-
I think that would be a bent control rod. The rod was not properly disconnected and when the upper internals were lifted and movement to the storage stand started it bent not allowing the upper internals to be moved. This was a CE plant where the Internal Core Instrumentation stored position is in the upper internals. RDTroja I believe you were also at that outage. If you have not been in the containment it is hard to relate dose in the R/hr range on the polar crane catwalk during the lift and movement of the internals to it's storage stand. I went in with one of the early crews trying to unlatch it but it was just the crane operator and another Rad tech on the walkway during the lift and movement.
Lessons learned were primarily for operations on control rod unlatching. Not much choice on how to handle the move after additional attempts to unlatch the rod as is.
-
That's a good one! Thanks Marlin!
-
What are the rules...did we have to actually be at the scene? Or was on site good enough?
The worst that comes to mind that I was actually there for was pipe-end decon during an SGRP. They lost their blast head ventilation (which they had assured us would immediately stop the shot-blast machine)...and then didn't even bother telling us they were having problems. We found out quickly enough...when our CAM alarmed...and the CAM on the refuel floor alarmed...and the CAM in the AUX bldg hallway alarmed...and...
As far as just being on site? During a S/G sleeving outage they dropped the >50 R/hr 'honing' (think vacuum filter that has been catching the fine dust generated by running a bottle brush up a generator tube) filter from the refuel floor to the basement. I was outside containment both (yes, BOTH - they didn't learn very fast) times this happened. The first time it wasn't TOO bad because the bag around the filter maintained some integrity...although the tech who was standing right there got the largest body burden I'd seen up to that point. The second time, the bag exploded, too, and we had minus eighth air all the way out in the access trailer. It was 'interesting' to do D&D in that quadrent when we tore the place down.
There's another 'war stories' thread in here somewhere, but...
-
If it is one that I witnessed from start to stop it would have to be a reactor head movement. I was standing on the refuel floor of containment (minding my own business) when I suddenly felt a high wind that started at my feet that moved up to my waist. I looked around to see what the heck it could be then looked up, the reactor head was being moved from the head stand and had passed over one of the ventilation units that exhausted straight up into the underside of the reactor head. I visualized massive ingestion and huge airborne but as it turned out the containment only hit 0.25 mpc (before DAC) and I showed no ingestion later on the body counter. Apparently dilution is the solution for pollution.
-
1. Three Mile Island (first 4 months after the accident)
2. Lesson learned, "Do Not Volunteer" to work a plant with ruptured fuel and 6" of primary water in the aux. building.
-
Pressurizer relief tank (PRT) had been drained and the valve left open to the reactor coolant drain tank. (RCDT)
Hydrogen migrated upward from the RCDT into the PRT.
HPT ascended a scaffold to reach the manhole at the top of the PRT, and raised an air sampler by rope.
HPT lowered the running air sampler into the PRT to obtain a sample.
“Rapid hydrogen burn” occurred within the PRT, shredding the HPT’s raingear coat, and nearly occurred knocking him 30 feet to the concrete.
Lessons Learned:
1. Your instrumentation is not intrinsically safe.
2. Communication, communication, communication.
3. There is a God.
-
What are the rules...did we have to actually be at the scene? Or was on site good enough?
The worst that comes to mind that I was actually there for was pipe-end decon during an SGRP. They lost their blast head ventilation (which they had assured us would immediately stop the shot-blast machine)...and then didn't even bother telling us they were having problems. We found out quickly enough...when our CAM alarmed...and the CAM on the refuel floor alarmed...and the CAM in the AUX bldg hallway alarmed...and...
As far as just being on site? During a S/G sleeving outage they dropped the >50 R/hr 'honing' (think vacuum filter that has been catching the fine dust generated by running a bottle brush up a generator tube) filter from the refuel floor to the basement. I was outside containment both (yes, BOTH - they didn't learn very fast) times this happened. The first time it wasn't TOO bad because the bag around the filter maintained some integrity...although the tech who was standing right there got the largest body burden I'd seen up to that point. The second time, the bag exploded, too, and we had minus eighth air all the way out in the access trailer. It was 'interesting' to do D&D in that quadrent when we tore the place down.
There's another 'war stories' thread in here somewhere, but...
I missed the lesson-learned part of the question, so...
On the first: Fail-Safes sometimes don't.
& second: Don't get so focused on one aspect of the job that you do something stupid on another part. A hook on a rope & pulley system was our standard way of moving waste from the basement to the refuel floor. The focus was on dose reduction, so a 'shepherd's hook' was made to lift the bagged filter from the rope hook. Long-handled tools...your standard ALARA friend, right? Unfortunately, on two occasions this led to HUGE contamination & airborne issues when filters were dropped and broken.
-
Duane Arnold Recirc pipe replacement in 1978/79. They welded in the pipe, when they tried to start up found that they had left a 10 lead plugs in the line.
-
this is all good stuff guys thank you
-
1. Person burned to death. I was on the emergency response team. 2. I told management we need to come in early to set up a pump of a tank full of strontium. The management would be useless watchers as we set up. Management said no come in regular time in July in TN and we would be pumping in a containment hut. Well since it was so hot for safety we had to do the final hook up with 4 different people doing 15 minute jumps. Would you know that it did not get hooked up right( should have been a one person job done in the morning) The line broke off the flange and sprayed strontium 90 all around the containment. Fortunately no one was in there. ( I was also scolded about the containment but w as grudgingly allowed to put it up.)
3. A company I was checking I told to change their RWP because it was poorly written and should have at least 3 things, Current conditions, hold points and a final survey. Well I get called later. They tell me a employee walked into their office and set off a frisker. ( He is now in TN but has shipped waste from SC) I was told that there was a 100 mr an hr hot spot in SC in a hospital. Old Cesium sources were crushed ( did not fit the right pig so they just smashed them in another pig, Unfortunately (Old) they disintegrated. Crapping up the hospital, the person (yes internally also) and container, Then crap up the vehicle while driving then crap up his house, then crap up his facility, This cost them in fines and clean up. They said from now on they will survey a facility they leave and have a person watch them survey to insure it was not crapped up. Also state conditions and hold points, Nice.
4. Numerous incidents, a boat trailer was crapped up with cesium found at a scrap yard, 20 mr/hr contact. Brass at a scrap yard with radioactive zinc and cobalt. Copper with Radioactive cobalt and silver. 100 R an hour contact radium source found at a bridal shop that was put in backwards in the pig, ( Fully exposed not shielded) (Nasopharyngeal source) doctor died years ago and no one knew what it was, Funny a spit bottle reading 200 mr/hr contact from I-131 thyroid ablation, Last 2 found by a fellow HP.
-
Setting off a stick of dynamite in the bottom of a Steam Generator Channel Head after a cycle with fuel problems.
-
Setting off a stick of dynamite in the bottom of a Steam Generator Channel Head after a cycle with fuel problems.
Explosive sleeving? ...or...?
-
Explosive sleeving? ...or...?
Explosive plugging... bad Boilermaker.
-
Does a nuke simulator count? I call this a almost screw up.
Well the Army made nuke simulators by digging a 50 foot ditch putting 2 sticks in the ends of the ditch and wrapping detonation cord 20 times around the sticks. A 600 gallon fuel truck would fill up 55 gallon drums with gas. We would put 2.5 tubs of thickener in each drum and then we would pour this into the ditch. Flares would be wrapped with the det cord. at the end of the ditch. The time fuse would be cut for 10 minutes. After several these went of I felt comfortable and let my Sergeants cut and measure this. They usually went off within 10 seconds of the 10 minutes. Well one time it did not go off. I waited 20 minutes still no boom. Being the safety officer I was responsible to go down range to see why there was no mushroom cloud. We discussed this and then there was a boom at about 25 minutes. I decided then I would always watch the det cord end being cut off to insure no moisture build up and I would watch it be measured after the end cut off for each shot. No more problems.
I also learned my Colonel was inaccurate when he told me it would always be a good nuclear day with a Nuclear Fusion star (The Sun) and no Mushroom clouds in the sky. I wanted to see the mushroom so I did not have to see why there was no mushroom. So No mushroom equals not a good day for me.
-
from: GLW on Jan 10, 2014, 05:54
death,...
Damn... beat me by a minute
OBE
Overcome By Edit
-
A real staff on-shifter 1979, 3-Mile and the few months following.
-
Does TMI count as radiological or operational?
A person could postulate it is both.
Yet, in our line of work, most operational SNAFU's have a high potential for prompting radiological challenges.
I would contend the root SNAFU is operational, the radiological challenges are collateral damages and do not distinctly qualify as radiological screw ups.
I'm just saying,...as I see it,... TMI is no Mr. Chips (yes I know Mr. Chips was set up for failure),... [coffee]
-
(yes I know Mr. Chips was set up for failure),... [coffee]
Not so much set up as it was a sign of the times. There was a shortage of techs at the time and inexperienced techs with little technical training was normal at many plants. "Mr Chips" was trying to be very conscientious and failed to recognize the difference in actual to indicated contact dose rate. He went farther than some of the techs would have to take care of his work crew and inadvertently received elevated exposure to his extremities. I was a lead tech on that project and had the opportunity to talk to him while he was going through all the critiques, I did and do think highly of him I suspect if he is still swinging a meter he is doing an exceptional job.
-
Watching a couple house tech sent to survey a "vent duct" to try and determine why QA's PD was offscale during fuel movement observations in the SFP. Turns out the vent duct was the transfer tube and seems when they built the plant they forgot to install any shielding around it.
lesson learned don't mess with spent fuel and just cause your told something don't blindly believe it
sf
-
The "vent duct" story sounds like a later version of the Trojan OE of 1978 when an HP and an Operator each received @ 25R while monitoring dose rates near the transfer canal. The HP from that day forward called Teletectors fence posts. All you new generation HPs will never experience off scale pencil dosimeters.
-
The "vent duct" story sounds like a later version of the Trojan OE of 1978 when an HP and an Operator each received @ 25R while monitoring dose rates near the transfer canal. The HP from that day forward called Teletectors fence posts. All you new generation HPs will never experience off scale pencil dosimeters.
That's one experience I don't mind not having. ;)
-
Cavity decon with pressure washers while the equipment hatch and personnel door were both open causing a "cyclone" type wind. Didn't witness it but relieved the crew that was there and dealt with the aftermath.
-
The "vent duct" story sounds like a later version of the Trojan OE of 1978 when an HP and an Operator each received @ 25R while monitoring dose rates near the transfer canal. The HP from that day forward called Teletectors fence posts. All you new generation HPs will never experience off scale pencil dosimeters.
Kinda correct but it was two house RP techs. At Trojan back then they were RadChem so one was actually a chemistry tech just sent along to help drag a meter. The doses that were initially reported were around 24 and 22 Rem at least from what I recall. Since nobody knew it was the transfer tube the two were standing about 6 feet from the tube when they heard a rattling noise as they looked around to try and determine the source of the noise, the Chem tech who had a R02 saw it peg and then the HP saw the teletector peg and then go to zero. I think the whole thing took about 45 seconds before the fuel assembly passed and they took off. When someone finally put two and two together they were both white as a sheet and the Chem tech was not very happy at all. Sent for medical evaluations in an effort to cya and the blood test all came back normal.
sf
sf
-
Kinda correct but it was two house RP techs. At Trojan back then they were RadChem so one was actually a chemistry tech just sent along to help drag a meter. The doses that were initially reported were around 24 and 22 Rem at least from what I recall. Since nobody knew it was the transfer tube the two were standing about 6 feet from the tube when they heard a rattling noise as they looked around to try and determine the source of the noise, the Chem tech who had a R02 saw it peg and then the HP saw the teletector peg and then go to zero. I think the whole thing took about 45 seconds before the fuel assembly passed and they took off. When someone finally put two and two together they were both white as a sheet and the Chem tech was not very happy at all. Sent for medical evaluations in an effort to cya and the blood test all came back normal.
sf
He was a Foreman during the 1980 Trojan outage I was at and I believe I was told there were detectable changes which is consistent with standards then. Blood changes were detectable at 5 Rem acute exposure with a baseline blood sample and 25 Rem without a baseline blood sample. Been a while I could be wrong.
-
Thanks for the updated info on Trojan. I had read the OE when it occurred in 1978 and then in late 1979 I left TMI for a fun filled 4 week adventure to Trojan when they had a number of admin. overexposures. Back in those days some plants welcomed the experience that road techs had to offer.
Anyway while at Trojan I became friends with the (at that time Chem. Tech) that was holding the Teletector when the fuel assembly passed. Then as stated earlier with pencil dosimeters they did not know their exposures until their TLDs were read. I seem to recall 23R and 27R but what is a few R between friends?
-
I started my nuclear career at Trojan, the day after this happened. It was my 27th birthday. Trojan was a great place to work.
-
Trojan was a great place to work.
Concur, even though we were vacuuming fuel pellets off of the spent fuel pool floor in 80. Met my current "BossLady" there and she still hasn't thrown me out after 33 years. ;)
-
actually there were three chemrad techs involved in the transfer canal fiasco at trojan but the third was short and couldn't get overall the wall so he received a lot less dose. if i remember was about 5 rem.
-
30+ years I seen all sides of it..I want to give a big ^5 out to all the HP's that jabbed me in the head with a teletector and say WTF..Now being a HP, I shake my head almost everyday, Im like really how stupid can ya be? Pre-job briefs don't seem to sink in. When your supervision and management won't support ya, your screwed..Way I look at it is ya fix stupid..Trust me I have tried...
-
..Way I look at it is ya fix stupid..
lemme no when yew start giving lessons, isle sine up for at least a bachelors degree worth. ;)
-
Slo here is my lesson who cares???? Bad thing is I always do... 8) :D
-
Dang! I was the tech in the crane. 1500 mrem/hour in the crane cab. Had to leave the crane when I reached 825 mrem. Wasn't anything I could help the crane operator with anyway. There was another couple of people (Harry Underwood RIP) and a spotter somewhere on the pressurizer house. Fun times.
I think that would be a bent control rod. The rod was not properly disconnected and when the upper internals were lifted and movement to the storage stand started it bent not allowing the upper internals to be moved. This was a CE plant where the Internal Core Instrumentation stored position is in the upper internals. RDTroja I believe you were also at that outage. If you have not been in the containment it is hard to relate dose in the R/hr range on the polar crane catwalk during the lift and movement of the internals to it's storage stand. I went in with one of the early crews trying to unlatch it but it was just the crane operator and another Rad tech on the walkway during the lift and movement.
Lessons learned were primarily for operations on control rod unlatching. Not much choice on how to handle the move after additional attempts to unlatch the rod as is.
-
Randy, remember when the inspection rig fell into vessel at Oconee 2. I'll never forget the look on that B&W techs face. All that along with the SG tube rupture and mrad on TB basement and LHRA on TB demins plus the HRA around pond on the hill. Things were quite different then.
-
Dang! I was the tech in the crane. 1500 mrem/hour in the crane cab. Had to leave the crane when I reached 825 mrem. Wasn't anything I could help the crane operator with anyway. There was another couple of people (Harry Underwood RIP) and a spotter somewhere on the pressurizer house. Fun times.
I understood that you used a SIT tank as a shadow shield during the movement. Fun times 8)
-
RE: Oconee - 10 mrem/hour beaver and highly contaminated frogs in the TB basement. After several days of smear, decon, smear, I quit screening bags of smears....bad move. Sent Carole O'Shaughnessy some smears reading 50 mrad…………….needless to say she wasn't happy after placing them on her tennelec :-)
GOOD TIMES
-
1980 finding 2mrem/hr on the beach at San Onofre, with kids playing in the sand.
-
Callaway. During initial installation, the (very thick) cables from the TLD (Temporary Lifting Device) for removing Steam Generators came crashing down from atop the polar crane onto the refuel floor, smashing the front windshield of the temp crane and sprawling out all over the floor like spaghetti. Amazing nobody was killed. I was told the hydraulics were installed backwards or something to that extent.
-
Callaway. During initial installation, the (very thick) cables from the TLD (Temporary Lifting Device) for removing Steam Generators came crashing down from atop the polar crane onto the refuel floor, smashing the front windshield of the temp crane and sprawling out all over the floor like spaghetti. Amazing nobody was killed. I was told the hydraulics were installed backwards or something to that extent.
I remember that. I was in the brief the day before when we were discussing welding the plates over the Hot/Cold legs area which had been cut off. The welding was to be performed while the SG was suspended by the TLD. A welder told the Mammoeut female engineer that all their training instructed them to "never work under a suspended load". The Eng. replied "the TLD will NEVER fail, it is impossible". That statement was proven wrong the next morning.
-
EXACTLY !!!.....I was going to go into more detail including that but I decided not to. I was also at that brief.
-
EXACTLY !!!.....I was going to go into more detail including that but I decided not to. I was also at that brief.
"Less is more" ;)
-
EXACTLY !!!.....I was going to go into more detail including that but I decided not to. I was also at that brief.
We worked side by side that Outage.
-
Callaway. During initial installation, the (very thick) cables from the TLD (Temporary Lifting Device) for removing Steam Generators came crashing down from atop the polar crane onto the refuel floor, smashing the front windshield of the temp crane and sprawling out all over the floor like spaghetti. Amazing nobody was killed. I was told the hydraulics were installed backwards or something to that extent.
I remember the sick feeling I got when I heard about that when I came in the next day hearing about it in the pre-shift brief...
-
Coming in on night shift to Waterford @1997 and finding a large portion of the area inside the protected area was posted as a contamination area. Seems someone misjudged and over flowed the spent fuel pool and it ran out under a roll up door to the outside. Let it be know that it was fine when I left and I was no where near the plant when it happened.
-
The hiring of back to back crazy RPM's at Indian Point. xxxxx, who quits every job and xxxxxxx, the furthest thing from being a team builder.
7. Peoples name's: It's a bad idea to use them, they lead to law suits. Some names are already censored because of this. Don't use names in stories or messages that could in any way be taken wrong.
https://www.nukeworker.com/forum/index.php/topic,4700.0.html
-
So many screwups, so little time. Conn Yankee 1989 operated 461 days straight. Set a world record for continuous operation and also continuous operation with failed fuel. Primary coolant activity was over 30 uc/ml (>3E+1)and the sample bottles were HiRad for several days after S/D. Mostly Iodine and Xenon.The A/S from S/G breach was high rad and oozed through the protective wrap and crapped up the MCA. CR tech didn't select bkgnd subtract and they thought there was iodine everywhere. We wore respirators in street clothes even though we couldn't take a protection factor. They already had an alpha problem, and this didn't add much to it because the fuel failure was pinholes and allowed gases to escape but retained solid material. I wasn't there for their previous events - ruptured fuel in the late 70s, ruptured PRT rupture disc in '85 that released reactor coolant to the stack, release of several hundred contaminated concrete blocks to several homes and businesses. Stay tuned for more thrilling stories from places like IP2, Yankee Rowe, Ginna, et. al. Back in the day when the term "radiological controls" was only a concept.
-
ANO 1st refuel they damaged a new fuel assembly trying to load into core and sent it back to spent fuel pool and removed from pool and laid it on floor with no notification of HP at all. Shift supervisor told HP supv he could send an HP tech up if he was going to help decon, if not , don't send one.
-
IP2 core barrel lift maybe 2005 or 2006. After briefing with the operating experience at Wolf Creek about lifting the barrel with low water, the SDRO gave the order to lift the barrel with low water. Lots of exposure and loss of his license. Followed by the explanation to the NRC that we did everything we could to prepare but at game time the operator didn't want to wait for the water, he wanted to finish the barrel move on his shift.
-
2-3 years ago some poor schmuck fell off an IVVI platform into the reactor cavity during an RFO. He was fine - took a bath and got 5 mrem dose. The bigger problem was that it was caught on one of the RP cameras and some moron took video of it on their cell phone and posted it to social media.
-
Decommissioning Humboldt Bay was basically like cleaning up a collection of 50+ years of radiological screw ups. What did I learn? That in the earliest days of commercial nuclear power, we were not very good at it. Oh yeah... And don't have a concrete spent fuel pool in one of the most earthquake prone area's of the world. ;-)
-
2-3 years ago some poor schmuck fell off an IVVI platform into the reactor cavity during an RFO. He was fine - took a bath and got 5 mrem dose. The bigger problem was that it was caught on one of the RP cameras and some moron took video of it on their cell phone and posted it to social media.
Sounds like CC last Feb/Mar. I knew it had reached peak 2018 when a resident NRC inspector asked if I had seen the video because it was sent to him.
-
Ok how does a guy actually fall in?
Nearest I ever saw was an engineer who actually crawled over a refueling crane rail because he wanted to look at something.
-
Ok how does a guy actually fall in?
Nearest I ever saw was an engineer who actually crawled over a refueling crane rail because he wanted to look at something.
I saw a man with an artificial leg trip and partially enter the fuel pool my initial impression was shock believing he was highly contaminated. Frisked out clean before decon of him and his artificial leg. Other than divers I have never seen anyone fully submerged in a fuel pool either.
-
Ok how does a guy actually fall in?
(https://media.tenor.com/images/67b8e3d263d84d4f7407eb7d8185a72e/tenor.gif)
-
I was a contractor HP for the CY outage of 1989, quite the eye opening experience. Common phrases used by house mouse's were piggyback beta and "everyone is crapping up the alpha meters "and we are going to pull them out of containment...ok, so we get to the SOP and "you are not bringing those smears out here". Then watching the house S/G lead on video in the S/G skirt going up the ladder in a lab coat, gloves and rubber boot covers ...no socks ..bare skin from his ankles...he left a trail of devastation for the next 10 years. heard he was delivering mail now...
Btw, I think I remember "the air sample" was 4000mpc ? Probably the most obtuse thing was that we had extra days off before the outage so that CY could run longer to make that record run...haha
-
Yankee Rowe late 1980s. They knew they had failed fuel. They were doing the fuel offload, picked up an element. While they were moving it, the top of a fuel pin fell off and rolled acres the cavity floor leaving a black trail behind. After draining the cavity, the Cavity Drain Line got up to 175 R/hr......Okay, I have to admit that this isn't the worst screw up I have witnessed, but it is notable.
-
Calvert cliffs decided to re-machine (can you say sawzall) the new thimble support plate IN THE Refuel Pool after they realized it was off quite a bit..... More than one RP tech said bad idea, FME bad. They said...oh no, we got this. 5 extra days of FOSAR equals how much $$$ ??? It was hard to see the bottom of the pool in some parts with all the shavings....wow. Hard to make this stuff up. 1986? no 2006.
-
A single fuel pin (in 4 pieces) is approximately 1R/hr at about 40 ft in air - Palisades 1993
-
A single fuel pin (in 4 pieces) is approximately 1R/hr at about 40 ft in air - Palisades 1993
Ah, the fun times at Palisades with the subsequent fuel fleas. In spite of that I did enjoy working there.
-
Lowering an air sampler into the top manway of the pressurized to collect a pre-entry air sample. Drain valve to the RCDT was open and allowed hydrogen back into the pressurized. The “rapid burn” blew off the tech’s rain gear. He did not fall 40 feet from the scaffold but had a look on his face I will never forget. Outside of CMNT it sounded like being on the inside of a tenor drum - loudest sound level I’ve ever experienced.
-
The outage after Fermi started Hydrogen Water Chemistry no one considered H2 might remain in the FW piping. Guys grinding on the pipe hit a pocket