1 00:00:01,280 --> 00:00:04,320 Speaker 1: Welcome to Stuff You Missed in History Class, a production 2 00:00:04,360 --> 00:00:13,720 Speaker 1: of I Heart Radio. Hello, and welcome to the podcast. 3 00:00:13,760 --> 00:00:17,720 Speaker 1: I'm Tracy B. Wilson and I'm Holly Fry. My friend Adrian, 4 00:00:17,840 --> 00:00:21,520 Speaker 1: who is a science educator, asked me years ago at 5 00:00:21,520 --> 00:00:24,040 Speaker 1: this point whether we had ever thought about doing an 6 00:00:24,040 --> 00:00:28,200 Speaker 1: episode on the Demon Core, which sounds terrifying, and I 7 00:00:28,320 --> 00:00:31,600 Speaker 1: kept thinking it might make a good October episode because 8 00:00:32,000 --> 00:00:37,560 Speaker 1: nuclear criticality accidents can be terrifying, like they expose people 9 00:00:37,720 --> 00:00:41,760 Speaker 1: to possibly lethal doses of radiation and just a fraction 10 00:00:41,800 --> 00:00:45,400 Speaker 1: of a second, usually completely by surprise and before anybody 11 00:00:45,440 --> 00:00:48,159 Speaker 1: can react, and then that leads to just a horrifying 12 00:00:48,240 --> 00:00:52,720 Speaker 1: and gruesome and sometimes prolonged death. Uh So, then every 13 00:00:52,760 --> 00:00:55,920 Speaker 1: October I kept moving on in other directions and not 14 00:00:55,960 --> 00:01:00,160 Speaker 1: getting to the Demon Core. Here it finally is. The 15 00:01:00,200 --> 00:01:04,880 Speaker 1: Demon Core was a sphere of plutonium gallium alloy that 16 00:01:04,959 --> 00:01:07,920 Speaker 1: the United States made for an atomic bomb during World 17 00:01:07,920 --> 00:01:11,400 Speaker 1: War Two, and then after the war, researchers at Los 18 00:01:11,440 --> 00:01:16,360 Speaker 1: Alamos National Laboratory had two separate fatal criticality accidents while 19 00:01:16,400 --> 00:01:19,800 Speaker 1: working with it. Those accidents are also part of a 20 00:01:19,880 --> 00:01:23,679 Speaker 1: greater history of criticality accidents, most of which took place 21 00:01:23,720 --> 00:01:25,640 Speaker 1: in the nineteen fifties and sixties, so we're going to 22 00:01:25,760 --> 00:01:30,520 Speaker 1: talk about that progression today just to set some expectations. 23 00:01:31,040 --> 00:01:34,600 Speaker 1: Nuclear reactor melt downs like the disasters at Three Mile 24 00:01:34,680 --> 00:01:38,000 Speaker 1: Island and Chernobyl and Fukushima, those are a slightly different 25 00:01:38,040 --> 00:01:41,440 Speaker 1: thing from what we're talking about today. Some of them 26 00:01:41,560 --> 00:01:44,920 Speaker 1: could technically be classified as criticality accidents, but they're also 27 00:01:44,959 --> 00:01:47,400 Speaker 1: just a little bit bigger and the topics that were 28 00:01:47,400 --> 00:01:50,360 Speaker 1: focused on, So it makes sense of how these incidents 29 00:01:50,400 --> 00:01:52,400 Speaker 1: play out. We need to walk through a little bit 30 00:01:52,440 --> 00:01:57,559 Speaker 1: of science history. In two James Chadwick discovered the uncharged 31 00:01:57,600 --> 00:02:01,800 Speaker 1: sub atomic particle known as the neutron, and soon physicists 32 00:02:01,800 --> 00:02:06,200 Speaker 1: were using neutrons to study atoms, including bombarding atomic nuclei 33 00:02:06,280 --> 00:02:09,880 Speaker 1: with neutrons to study the results. It was through this 34 00:02:09,919 --> 00:02:13,880 Speaker 1: work that Otto han Lee's Mightner and Fritz Strassman discovered 35 00:02:13,960 --> 00:02:18,799 Speaker 1: nuclear fission. In night. Han had been working with uranium 36 00:02:18,840 --> 00:02:21,919 Speaker 1: samples that had been bombarded with neutrons, and for reasons 37 00:02:21,919 --> 00:02:26,560 Speaker 1: that they couldn't really explain, barium isotopes started appearing in 38 00:02:26,600 --> 00:02:30,639 Speaker 1: his samples as well. Mightner and Strassmann made the connection 39 00:02:30,720 --> 00:02:34,280 Speaker 1: that barium has about half the atomic mass of uranium, 40 00:02:34,360 --> 00:02:38,480 Speaker 1: so the uranium atoms were splitting into two roughly equal parts. 41 00:02:39,160 --> 00:02:41,960 Speaker 1: The idea that an atom could split in this way 42 00:02:42,120 --> 00:02:45,080 Speaker 1: had been suggested before, but it was not really taken 43 00:02:45,120 --> 00:02:48,600 Speaker 1: seriously at the time because it seemed absolutely contrary to 44 00:02:48,639 --> 00:02:53,239 Speaker 1: how people understood nuclear physics at that point. This breakdown 45 00:02:53,360 --> 00:02:56,880 Speaker 1: of uranium into barium didn't answer all the questions, though 46 00:02:57,600 --> 00:03:01,160 Speaker 1: Mightner also calculated that the two new arium nuclei would 47 00:03:01,160 --> 00:03:04,680 Speaker 1: be slightly less massive than the original uranium nucleus, with 48 00:03:04,760 --> 00:03:08,880 Speaker 1: the difference converted into energy. Auto Han was awarded the 49 00:03:08,919 --> 00:03:12,000 Speaker 1: Nobel Prize in Chemistry for the discovery of nuclear fission 50 00:03:12,080 --> 00:03:16,400 Speaker 1: in nine four. Although Miightner and Strassmann were mentioned in 51 00:03:16,400 --> 00:03:20,359 Speaker 1: the speech, they were not included in that award. Nuclear 52 00:03:20,400 --> 00:03:24,360 Speaker 1: fission can happen spontaneously in the natural world, and the 53 00:03:24,440 --> 00:03:27,080 Speaker 1: details can play out a little bit differently in different 54 00:03:27,160 --> 00:03:30,120 Speaker 1: elements and isotopes, but in terms of what we're talking 55 00:03:30,120 --> 00:03:34,160 Speaker 1: about today, it typically starts with neutrons. Neutrons interact with 56 00:03:34,200 --> 00:03:38,200 Speaker 1: the atoms nucleus, causing it to split. That split releases 57 00:03:38,320 --> 00:03:41,560 Speaker 1: one or more other neutrons, and in the right conditions, 58 00:03:41,600 --> 00:03:45,200 Speaker 1: those neutrons can reach the nuclei of other nearby atoms, 59 00:03:45,240 --> 00:03:48,320 Speaker 1: causing them to split that can continue on in a 60 00:03:48,440 --> 00:03:52,320 Speaker 1: chain reaction. If there's enough material in one place to 61 00:03:52,360 --> 00:03:57,280 Speaker 1: support a regular, ongoing, self sustaining chain reaction, that's known 62 00:03:57,320 --> 00:04:00,560 Speaker 1: as critical mass. In a super critic a mass, this 63 00:04:00,800 --> 00:04:04,160 Speaker 1: chain reaction unfolds at an escalating rate instead of a 64 00:04:04,160 --> 00:04:08,200 Speaker 1: steady one. It's not just about how much physical material 65 00:04:08,440 --> 00:04:11,520 Speaker 1: is in one place though the volume of the material. 66 00:04:11,760 --> 00:04:16,200 Speaker 1: It's geometry, it's concentration, its surroundings, and other factors all 67 00:04:16,279 --> 00:04:20,000 Speaker 1: play apart. As a hypothetical example, if you have a 68 00:04:20,120 --> 00:04:23,520 Speaker 1: very thin sheet of uranium two thirty five, a lot 69 00:04:23,560 --> 00:04:25,920 Speaker 1: of the neutrons that are released during fission are going 70 00:04:25,960 --> 00:04:28,920 Speaker 1: to fly off into the surrounding air without hitting any 71 00:04:29,080 --> 00:04:32,400 Speaker 1: uranium atoms. But if you have the same amount of 72 00:04:32,520 --> 00:04:35,919 Speaker 1: uranium two thirty five packed into a tight sphere, the 73 00:04:36,040 --> 00:04:39,480 Speaker 1: neutrons from the interior are far more likely to interact 74 00:04:39,480 --> 00:04:43,760 Speaker 1: with other nuclei as they travel, potentially starting a chain reaction. 75 00:04:44,360 --> 00:04:47,839 Speaker 1: So the elements that break down in these interactions are radioactive, 76 00:04:48,040 --> 00:04:51,760 Speaker 1: and the products of fission are generally radioactive as well. 77 00:04:52,440 --> 00:04:56,320 Speaker 1: The energy that's released during nuclear fission, which there can 78 00:04:56,360 --> 00:05:00,800 Speaker 1: be a lot of also includes ionizing radiation, and while 79 00:05:00,800 --> 00:05:04,599 Speaker 1: ionizing radiation has some beneficial uses, it can also be 80 00:05:04,720 --> 00:05:10,400 Speaker 1: incredibly destructive to living cells. Criticality accidents can expose people 81 00:05:10,520 --> 00:05:14,520 Speaker 1: and objects to just enormous amounts of radiation in an instant, 82 00:05:14,560 --> 00:05:18,359 Speaker 1: so facilities that handle these types of materials have to 83 00:05:18,400 --> 00:05:21,839 Speaker 1: take a lot of precautions to protect people from radiation 84 00:05:22,400 --> 00:05:25,679 Speaker 1: and to prevent an accidental criticality, which is sometimes also 85 00:05:25,760 --> 00:05:29,880 Speaker 1: called a power excursion. This includes restrictions on how much 86 00:05:30,000 --> 00:05:32,840 Speaker 1: material can be in a particular place and how it 87 00:05:32,880 --> 00:05:36,400 Speaker 1: should be handled. Containers to hold the material have to 88 00:05:36,440 --> 00:05:39,280 Speaker 1: be shaped in a way that is unfavorable for criticality 89 00:05:39,720 --> 00:05:42,479 Speaker 1: and made of materials that won't reflect too many sub 90 00:05:42,480 --> 00:05:46,599 Speaker 1: atomic particles back into the material, and people handling the 91 00:05:46,640 --> 00:05:51,400 Speaker 1: material have to be trained on how to prevent criticality accidents. 92 00:05:51,440 --> 00:05:55,920 Speaker 1: Some of this can be a little counterintuitive to outside observers. 93 00:05:56,560 --> 00:06:00,479 Speaker 1: For example, if you saw some plutonium rods play near 94 00:06:00,520 --> 00:06:03,240 Speaker 1: each other in a way that could potentially lead to 95 00:06:03,320 --> 00:06:07,000 Speaker 1: a criticality, your first instinct might be to move them 96 00:06:07,080 --> 00:06:09,480 Speaker 1: apart so that they would not do that. But a 97 00:06:09,520 --> 00:06:13,920 Speaker 1: person's own body can also reflect neutrons back at the material, 98 00:06:14,040 --> 00:06:16,960 Speaker 1: so that very act of trying to prevent a criticality 99 00:06:17,000 --> 00:06:21,280 Speaker 1: accident could actually wind up causing one instead. This is 100 00:06:21,320 --> 00:06:24,840 Speaker 1: a real example. It happened at Los Alamos National Laboratory 101 00:06:24,880 --> 00:06:28,280 Speaker 1: in August of eleven after somebody made an arrangement of 102 00:06:28,279 --> 00:06:33,719 Speaker 1: plutonium rods for a photo op. Fortunately, while what happened 103 00:06:33,880 --> 00:06:36,880 Speaker 1: was outside the bounds of safety guidelines, it did not 104 00:06:37,040 --> 00:06:42,039 Speaker 1: cause a criticality accident. Because nuclear fission releases energy, its 105 00:06:42,080 --> 00:06:46,400 Speaker 1: discovery had immediate and obvious implications for both energy production 106 00:06:46,560 --> 00:06:50,640 Speaker 1: and warfare, and multiple nations started trying to develop nuclear 107 00:06:50,680 --> 00:06:54,400 Speaker 1: reactors and atomic bombs. In the United States, the effort 108 00:06:54,440 --> 00:06:57,520 Speaker 1: to develop an atomic bomb was codenamed the Manhattan Project, 109 00:06:57,920 --> 00:07:01,440 Speaker 1: which also involved the construction of clear reactors to produce 110 00:07:01,520 --> 00:07:05,880 Speaker 1: the necessary radioactive materials for the bomb. For the most part, 111 00:07:05,960 --> 00:07:11,120 Speaker 1: the reactors converted naturally occurring uranium into uranium and plutonium fuel. 112 00:07:11,880 --> 00:07:14,920 Speaker 1: Most of the natural uranium that was used in American 113 00:07:14,960 --> 00:07:17,920 Speaker 1: projects during World War Two was mined and what was 114 00:07:18,000 --> 00:07:20,840 Speaker 1: then the Belgian Congo, and then after the war, that 115 00:07:20,960 --> 00:07:26,480 Speaker 1: source shifted to the Navajo Nation and surrounding areas. The environmental, 116 00:07:26,680 --> 00:07:30,720 Speaker 1: human rights and health consequences of these uranium mining operations, 117 00:07:30,840 --> 00:07:34,880 Speaker 1: some of which are extreme, are still ongoing today. For example, 118 00:07:34,920 --> 00:07:39,120 Speaker 1: there are still hundreds of abandoned uranium mines on or 119 00:07:39,240 --> 00:07:42,679 Speaker 1: near the lands of multiple indigenous nations in the US, 120 00:07:43,360 --> 00:07:45,640 Speaker 1: and even though the e p A has entered into 121 00:07:45,680 --> 00:07:50,520 Speaker 1: settlements totaling one point seven billion dollars, those settlements covered 122 00:07:50,600 --> 00:07:53,960 Speaker 1: clean up for fewer than half of these mines, and 123 00:07:54,040 --> 00:07:57,119 Speaker 1: almost none of them have actually been addressed at this point. 124 00:07:57,640 --> 00:08:01,240 Speaker 1: Although nuclear research took place at multi full facilities around 125 00:08:01,240 --> 00:08:04,800 Speaker 1: the country, the primary lamb for atomic bomb development in 126 00:08:04,840 --> 00:08:09,560 Speaker 1: the US was in Los Alamos, New Mexico. Simultaneously, researchers 127 00:08:09,560 --> 00:08:12,400 Speaker 1: had to figure out the technology for the bomb, produced 128 00:08:12,440 --> 00:08:15,360 Speaker 1: the nuclear material to power it, and figure out how 129 00:08:15,400 --> 00:08:19,000 Speaker 1: to handle that material safely without accidentally allowing it to 130 00:08:19,040 --> 00:08:22,640 Speaker 1: go critical or supercritical, all while trying to create a 131 00:08:22,640 --> 00:08:25,960 Speaker 1: weapon that was supposed to go super critical. One of 132 00:08:26,000 --> 00:08:28,800 Speaker 1: the bombs that was created through the Manhattan Project was 133 00:08:28,880 --> 00:08:31,960 Speaker 1: known as Little Boy. Then it was detonated over Hiroshima, 134 00:08:32,040 --> 00:08:37,720 Speaker 1: Japan on August. This bomb contained a subcritical mass of 135 00:08:37,920 --> 00:08:43,400 Speaker 1: enriched uranium along with a subcritical uranium projectile. A gun 136 00:08:43,840 --> 00:08:47,440 Speaker 1: fired the projectile into the mass, and together the mass 137 00:08:47,480 --> 00:08:51,720 Speaker 1: and the projectile were super critical. This bomb was equivalent 138 00:08:51,760 --> 00:08:55,400 Speaker 1: to about fifteen thousand tons of T and T. It 139 00:08:55,679 --> 00:08:59,959 Speaker 1: killed an estimated hundred and fifty thousand people and level 140 00:09:00,120 --> 00:09:03,600 Speaker 1: much of the city. The Manhattan Project also produced three 141 00:09:03,640 --> 00:09:07,280 Speaker 1: plutonium cores to be used in implosion style bombs during 142 00:09:07,320 --> 00:09:10,880 Speaker 1: World War Two. In this setup, the plutonium core is 143 00:09:10,920 --> 00:09:16,160 Speaker 1: surrounded by conventional explosives. When those explosives detonate, they compress 144 00:09:16,240 --> 00:09:19,679 Speaker 1: the core, causing it to go from subcritical to supercritical. 145 00:09:20,679 --> 00:09:23,320 Speaker 1: One of these cores was detonated at a test at 146 00:09:23,320 --> 00:09:26,240 Speaker 1: the Alama Gordo Bombing and Gunnery Range also called the 147 00:09:26,280 --> 00:09:31,360 Speaker 1: Trinity Site, on July sixteenth, ninety five. Another was used 148 00:09:31,360 --> 00:09:33,840 Speaker 1: in the bomb known as Fat Man, which was detonated 149 00:09:33,840 --> 00:09:38,240 Speaker 1: over Nagasaki, Japan, on August nine, ninety five, killing and 150 00:09:38,400 --> 00:09:43,280 Speaker 1: estimated seventy five thousand people. The third plutonium core was 151 00:09:43,440 --> 00:09:48,640 Speaker 1: nearing completion when Japan announced its surrender on August fifty five, 152 00:09:48,760 --> 00:09:53,079 Speaker 1: meaning that it was no longer needed for World War two. Later, 153 00:09:53,360 --> 00:09:56,960 Speaker 1: the U S started planning Operation Crossroads, which was a 154 00:09:57,000 --> 00:10:00,599 Speaker 1: test of nuclear weapons effects on worship at Seed to 155 00:10:00,679 --> 00:10:04,920 Speaker 1: take place off Bikini at all. This third core, the 156 00:10:04,960 --> 00:10:07,240 Speaker 1: one that would later be nicknamed the Demon Core, was 157 00:10:07,240 --> 00:10:10,880 Speaker 1: slated for use in these tests, but in the meantime 158 00:10:10,960 --> 00:10:13,960 Speaker 1: it was used for criticality research. It was during that 159 00:10:14,080 --> 00:10:17,600 Speaker 1: research that they nicknamed it the Demon Core, even though 160 00:10:17,720 --> 00:10:21,400 Speaker 1: to be clear, did not kill nearly as many people 161 00:10:22,520 --> 00:10:26,520 Speaker 1: as the other two that were detonated over cities. And 162 00:10:26,559 --> 00:10:28,680 Speaker 1: we're going to talk more about the Demon Core after 163 00:10:28,720 --> 00:10:39,480 Speaker 1: we first paused for a sponsor break. The plutonium core 164 00:10:39,679 --> 00:10:45,000 Speaker 1: that was eventually nicknamed the Demon Core was originally nicknamed Rufus. 165 00:10:45,400 --> 00:10:48,560 Speaker 1: I don't know why, but so many sources have said 166 00:10:48,600 --> 00:10:53,679 Speaker 1: that that seems legitimate. It was a six point to 167 00:10:54,040 --> 00:10:58,200 Speaker 1: kill agram or thirteen point seven pounds sphere, really two 168 00:10:58,400 --> 00:11:04,040 Speaker 1: hemispheres made of a fine plutonium and gallium. Under normal conditions, 169 00:11:04,120 --> 00:11:08,080 Speaker 1: it was of a critical mass, so it's often described 170 00:11:08,080 --> 00:11:11,280 Speaker 1: as having a hair trigger, although it had been created 171 00:11:11,320 --> 00:11:13,920 Speaker 1: for use in a bomb. This hair trigger also made 172 00:11:13,920 --> 00:11:19,600 Speaker 1: the core useful for criticality experiments. Physicists could intentionally reflect 173 00:11:19,679 --> 00:11:22,360 Speaker 1: neutrons back at the core to push it close to 174 00:11:22,440 --> 00:11:27,680 Speaker 1: criticality and gathered data about what was happening. Physicist Richard Feynman, 175 00:11:27,760 --> 00:11:30,600 Speaker 1: whose work with the Manhattan Project included helping to work 176 00:11:30,600 --> 00:11:35,319 Speaker 1: out standards to prevent criticality accidents. Reportedly nicknamed these types 177 00:11:35,360 --> 00:11:42,760 Speaker 1: of experiments tickling the Dragon's Tail. On August one, four 178 00:11:42,840 --> 00:11:46,680 Speaker 1: year old graduate student Harry Dallian Jr. Was working by 179 00:11:46,800 --> 00:11:49,520 Speaker 1: himself in the lab. Because of the nature of the 180 00:11:49,559 --> 00:11:51,800 Speaker 1: work that was being done at Los Alamos, like it 181 00:11:51,880 --> 00:11:54,360 Speaker 1: was critical to the war effort, it involved part of 182 00:11:54,360 --> 00:11:58,599 Speaker 1: the nation's nuclear material stockpile, it was standard for security 183 00:11:58,600 --> 00:12:01,840 Speaker 1: guards to always be asn't so. Even though Dallian was 184 00:12:01,880 --> 00:12:04,960 Speaker 1: working alone on this experiment, there was one other person 185 00:12:05,080 --> 00:12:07,959 Speaker 1: in the room. That was twenty nine year old Private 186 00:12:08,080 --> 00:12:11,079 Speaker 1: Robert Hamerley, who was sitting at a table about twelve 187 00:12:11,120 --> 00:12:15,120 Speaker 1: feet away from the core. Dallian was using tungsten carbide 188 00:12:15,160 --> 00:12:18,440 Speaker 1: bricks to build a reflective wall around the plutonium core 189 00:12:18,559 --> 00:12:22,439 Speaker 1: by hand. The bricks reflected neutrons back at the core, 190 00:12:22,679 --> 00:12:26,520 Speaker 1: inching it closer to criticality. The more bricks he added, 191 00:12:26,559 --> 00:12:29,520 Speaker 1: the more neutrons were reflected, and the closer the core 192 00:12:29,600 --> 00:12:33,040 Speaker 1: got to going critical. As Dallian was about to add 193 00:12:33,080 --> 00:12:37,200 Speaker 1: the last brick in this structure, his instruments showed that 194 00:12:37,360 --> 00:12:40,480 Speaker 1: doing so was going to cause the core to go critical, 195 00:12:40,679 --> 00:12:44,240 Speaker 1: so he tried to pull that last brick away, but 196 00:12:44,320 --> 00:12:47,000 Speaker 1: as he did, it slipped out of his hand and 197 00:12:47,080 --> 00:12:51,320 Speaker 1: dropped directly onto the core. Daalian used his other hand 198 00:12:51,360 --> 00:12:54,120 Speaker 1: to knock the dropped brick away, but it was too late. 199 00:12:54,679 --> 00:12:56,959 Speaker 1: There was a wave of heat and a brief flash 200 00:12:57,000 --> 00:12:59,640 Speaker 1: of blue light all around the exterior of the sphere. 201 00:13:00,400 --> 00:13:03,400 Speaker 1: That light was probably Chrinkov radiation, which is the result 202 00:13:03,440 --> 00:13:06,280 Speaker 1: of charged particles moving faster than the speed of light 203 00:13:06,600 --> 00:13:11,520 Speaker 1: through a transparent medium like air. In that brief moment 204 00:13:11,800 --> 00:13:14,800 Speaker 1: between when he dropped the brick and when he knocked 205 00:13:14,800 --> 00:13:18,559 Speaker 1: it away, Dallian was hit with a blast of neutron radiation. 206 00:13:19,200 --> 00:13:22,520 Speaker 1: He disassembled the reflector that he had built, and that 207 00:13:22,640 --> 00:13:26,320 Speaker 1: continued to expose him to gamma radiation while he was 208 00:13:26,360 --> 00:13:30,960 Speaker 1: doing so. Today, absorbed radiation is measured in gray, with 209 00:13:31,080 --> 00:13:35,559 Speaker 1: one gray being equivalent to one RADS. A sudden whole 210 00:13:35,600 --> 00:13:38,560 Speaker 1: body dose of zero point seven gray is enough to 211 00:13:38,600 --> 00:13:43,240 Speaker 1: cause acute radiation sickness. Sometimes symptoms can develop at as 212 00:13:43,280 --> 00:13:47,720 Speaker 1: little as zero point three gray. Dallian's dose was estimated 213 00:13:47,800 --> 00:13:51,520 Speaker 1: at five point one gray. He died twenty five days 214 00:13:51,559 --> 00:13:57,680 Speaker 1: after the accident. On September Private Hammerley's dose was estimated 215 00:13:57,720 --> 00:14:02,319 Speaker 1: at zero point five gray. He survived this incident apparently 216 00:14:02,400 --> 00:14:05,720 Speaker 1: without serious injury at the time. If you read older 217 00:14:05,880 --> 00:14:08,960 Speaker 1: articles that were published before his death later on like 218 00:14:09,000 --> 00:14:12,360 Speaker 1: they'll say that that he wasn't seriously harmed, but he 219 00:14:12,360 --> 00:14:15,320 Speaker 1: wound up dying of leukemia which might have been related 220 00:14:15,360 --> 00:14:19,400 Speaker 1: to this radiation exposure, when he was sixty two. Afterward, 221 00:14:19,600 --> 00:14:24,280 Speaker 1: criticality experiments continued at Los Alamos in spite of this fatality, 222 00:14:24,320 --> 00:14:28,080 Speaker 1: although some new safety standards were put into play. The 223 00:14:28,200 --> 00:14:31,120 Speaker 1: list of people allowed to do these kinds of experiments 224 00:14:31,160 --> 00:14:34,640 Speaker 1: was shortened, with two sets of monitoring equipment required for 225 00:14:34,720 --> 00:14:39,080 Speaker 1: each experiment. The new standards reiterated that at least two 226 00:14:39,120 --> 00:14:42,120 Speaker 1: people in addition to the guard, had to be present 227 00:14:42,200 --> 00:14:45,880 Speaker 1: for this kind of work. Researchers also started discussing whether 228 00:14:45,920 --> 00:14:48,840 Speaker 1: it would be better to do these kinds of experiments remotely, 229 00:14:49,240 --> 00:14:51,640 Speaker 1: so that if a criticality did happen, it would be 230 00:14:51,680 --> 00:14:55,680 Speaker 1: too far away from people to hurt them. Operation Crossroads 231 00:14:55,720 --> 00:15:00,320 Speaker 1: was scheduled to start in July, but before the core 232 00:15:00,560 --> 00:15:03,120 Speaker 1: was sent to the Marshall Islands to be used there, 233 00:15:03,400 --> 00:15:07,800 Speaker 1: physicists were doing one last set of criticality experiments with it. 234 00:15:08,400 --> 00:15:13,720 Speaker 1: On May one, Canadian physicist Louis Slowton was using a 235 00:15:13,840 --> 00:15:17,800 Speaker 1: hollow beryllium sphere to mostly cover up the core and 236 00:15:17,840 --> 00:15:22,400 Speaker 1: reflect neutrons back into it. The sphere had two halves 237 00:15:22,480 --> 00:15:24,880 Speaker 1: that the core was sort of resting in the bottom half, 238 00:15:25,360 --> 00:15:28,160 Speaker 1: and he had his thumb threaded through a hole in 239 00:15:28,240 --> 00:15:30,960 Speaker 1: the top half so that he could adjust the positioning 240 00:15:30,960 --> 00:15:34,320 Speaker 1: of this sort of dome with his hand. He knew 241 00:15:34,360 --> 00:15:38,400 Speaker 1: that if the sphere closed completely, it could cause a criticality, 242 00:15:38,560 --> 00:15:42,040 Speaker 1: so he used the end of a screwdriver to keep 243 00:15:42,080 --> 00:15:45,560 Speaker 1: the two halves slightly separate. This sounds like the kind 244 00:15:45,600 --> 00:15:47,560 Speaker 1: of thing I would do at my house with something 245 00:15:47,560 --> 00:15:50,080 Speaker 1: that is not dangerous, and even so my husband would go, 246 00:15:50,280 --> 00:15:52,920 Speaker 1: are you sure that's how you want to do it? Yes? Yes, 247 00:15:53,080 --> 00:15:57,360 Speaker 1: I have a story on this subject about myself that 248 00:15:57,400 --> 00:16:01,160 Speaker 1: I will probably tell in our Friday behind the Scene fabulous. 249 00:16:01,720 --> 00:16:06,240 Speaker 1: While while I have some understanding of how a person 250 00:16:06,320 --> 00:16:09,240 Speaker 1: might do a really foolish thing, knowing how foolish it is, 251 00:16:09,840 --> 00:16:16,880 Speaker 1: I was not handling potentially critical nuclear weapons cores at 252 00:16:16,880 --> 00:16:21,440 Speaker 1: the time. As he was doing this, the screwdriver slipped 253 00:16:21,560 --> 00:16:25,320 Speaker 1: and the dome totally closed, there was a brief flash 254 00:16:25,400 --> 00:16:28,240 Speaker 1: of blue light that was visible over the normal illumination 255 00:16:28,280 --> 00:16:31,200 Speaker 1: of the room. This lasted only a moment as Slowtan 256 00:16:31,240 --> 00:16:34,480 Speaker 1: flipped the dome off of the core. Slowton seems to 257 00:16:34,560 --> 00:16:38,360 Speaker 1: have immediately understood that he was not going to survive 258 00:16:38,480 --> 00:16:43,280 Speaker 1: this accident, saying, well, that does it. In general, a 259 00:16:43,400 --> 00:16:47,160 Speaker 1: whole body radiation dose of more than ten gray is 260 00:16:47,280 --> 00:16:52,280 Speaker 1: inevitably fatal, and his has been estimated at twenty one gray. 261 00:16:52,680 --> 00:16:55,080 Speaker 1: At the same time, he had the presence of mind 262 00:16:55,120 --> 00:16:58,440 Speaker 1: to try to document where the other seven observers in 263 00:16:58,440 --> 00:17:00,880 Speaker 1: the room had been standing at the time, and then 264 00:17:00,880 --> 00:17:03,560 Speaker 1: to try to calculate how large of a dose of 265 00:17:03,640 --> 00:17:08,080 Speaker 1: radiation each of them received. Their doses have been estimated 266 00:17:08,080 --> 00:17:11,560 Speaker 1: as ranging between zero point three seven and three point 267 00:17:11,680 --> 00:17:15,919 Speaker 1: six grade. Slodan also tried to detect how much radiation 268 00:17:16,000 --> 00:17:18,840 Speaker 1: was present in other objects that were in the room, 269 00:17:18,920 --> 00:17:22,480 Speaker 1: but the detectors themselves had been contaminated in the accident. 270 00:17:22,880 --> 00:17:27,040 Speaker 1: At the same time, he wasn't thinking entirely clearly. He 271 00:17:27,080 --> 00:17:30,119 Speaker 1: asked a colleague to scatter film badges used to detect 272 00:17:30,240 --> 00:17:34,440 Speaker 1: radiation exposure around the area, and that required the colleague 273 00:17:34,480 --> 00:17:37,080 Speaker 1: to get close to the radioactive Corps to do so. 274 00:17:37,760 --> 00:17:40,840 Speaker 1: Slowtan died nine days after this accident at the age 275 00:17:40,840 --> 00:17:44,280 Speaker 1: of thirty five, and although he was the only person killed, 276 00:17:44,400 --> 00:17:47,240 Speaker 1: three other people in the room had to be hospitalized 277 00:17:47,240 --> 00:17:51,840 Speaker 1: for acute radiation exposure, and one of them was Alvin C. Graves, 278 00:17:51,920 --> 00:17:55,680 Speaker 1: who was the closest to Slotan physically. When this accident happened. 279 00:17:55,960 --> 00:18:00,720 Speaker 1: Slotan had actually been training Graves as his replacement. Graves 280 00:18:00,840 --> 00:18:03,199 Speaker 1: was seriously injured and for a time it was not 281 00:18:03,359 --> 00:18:06,320 Speaker 1: certain whether he was going to survive. He later developed 282 00:18:06,359 --> 00:18:09,800 Speaker 1: cataracts and thyroid issues, and his death from a heart 283 00:18:09,800 --> 00:18:14,080 Speaker 1: attack nineteen years later may also have been related. In general, 284 00:18:14,320 --> 00:18:17,840 Speaker 1: people have viewed Harry Dallian Junior's accident with a bit 285 00:18:17,880 --> 00:18:21,960 Speaker 1: more sympathy than Lewis Slowtan's. Dallian was working alone, which 286 00:18:22,000 --> 00:18:25,159 Speaker 1: was against protocol, but he was also a graduate student, 287 00:18:25,280 --> 00:18:29,400 Speaker 1: so he was not as experienced as many of his colleagues. Slotan, 288 00:18:29,520 --> 00:18:32,000 Speaker 1: on the other hand, was not only a senior scientist, 289 00:18:32,080 --> 00:18:34,760 Speaker 1: but had also co authored the official report on the 290 00:18:34,840 --> 00:18:39,000 Speaker 1: accident that had killed Harry Dallian, so he definitely understood 291 00:18:39,000 --> 00:18:42,879 Speaker 1: the risks and the potential for accident. His experiment was 292 00:18:42,920 --> 00:18:45,960 Speaker 1: meant to be done with two one inch spacers between 293 00:18:46,000 --> 00:18:49,400 Speaker 1: the two halves of the Billiam sphere, but Slowtan had 294 00:18:49,440 --> 00:18:52,639 Speaker 1: removed these and was using the screwdriver in their place. 295 00:18:53,640 --> 00:18:57,320 Speaker 1: Multiple other scientists who were aware of the criticality experiment 296 00:18:57,359 --> 00:19:00,560 Speaker 1: he was doing thought it was inordinately danger risks, and 297 00:19:00,680 --> 00:19:03,760 Speaker 1: in general he had a reputation for being a little 298 00:19:03,760 --> 00:19:09,040 Speaker 1: too cavalier around things like atomic bomb cores. Scientists nicknamed 299 00:19:09,040 --> 00:19:12,040 Speaker 1: this core the demon Core, not just because it had 300 00:19:12,080 --> 00:19:15,000 Speaker 1: been part of both of these fatal accidents, but also 301 00:19:15,119 --> 00:19:19,200 Speaker 1: because of some eerie similarities between them. Both accidents took 302 00:19:19,240 --> 00:19:21,199 Speaker 1: placed on the twenty one of the month and on 303 00:19:21,240 --> 00:19:24,480 Speaker 1: a Tuesday, and Slotan and Dalian both died in the 304 00:19:24,520 --> 00:19:27,600 Speaker 1: same hospital room at the U S Engineer's Hospital at 305 00:19:27,640 --> 00:19:31,040 Speaker 1: Los Alamos. By this point, work had started on a 306 00:19:31,080 --> 00:19:35,360 Speaker 1: remote facility for criticality experiments, and after the second accident 307 00:19:35,400 --> 00:19:39,040 Speaker 1: with the Demon Core, hands on criticality experiments like this 308 00:19:39,119 --> 00:19:44,960 Speaker 1: were banned in criticality experiments resumed at the newly completed 309 00:19:45,000 --> 00:19:49,040 Speaker 1: critical experiments facility at what was known as the Pajarito Site. 310 00:19:49,440 --> 00:19:53,040 Speaker 1: Criticality experiments there were handled with machinery and took place 311 00:19:53,119 --> 00:19:55,639 Speaker 1: a quarter mile from the control room where the people 312 00:19:55,680 --> 00:19:59,639 Speaker 1: doing the experiments were. Since the amount of radiation drops 313 00:19:59,720 --> 00:20:02,119 Speaker 1: from actically the farther you are away from the source, 314 00:20:02,400 --> 00:20:05,760 Speaker 1: this was much safer than doing something like stacking reflective 315 00:20:05,800 --> 00:20:09,440 Speaker 1: blocks with your hands. Dallian and Slotan were the only 316 00:20:09,520 --> 00:20:13,960 Speaker 1: two people to die from acute radiation exposure at Los 317 00:20:14,000 --> 00:20:18,160 Speaker 1: Alamos during the Manhattan Project. Although there were numerous other 318 00:20:18,280 --> 00:20:21,160 Speaker 1: deaths in and around the facility during those same years, 319 00:20:21,680 --> 00:20:24,159 Speaker 1: a lot of them were from accidents that had nothing 320 00:20:24,240 --> 00:20:28,520 Speaker 1: to do with radioactive materials or bombs. This included motor 321 00:20:28,600 --> 00:20:32,400 Speaker 1: vehicle accidents, construction accidents, and in one case, a ten 322 00:20:32,520 --> 00:20:37,119 Speaker 1: year old who drowned when a canoe capsized. In six 323 00:20:37,280 --> 00:20:41,720 Speaker 1: three custodians also died of ethylene glycol poisoning after drinking 324 00:20:41,800 --> 00:20:44,879 Speaker 1: wine that was mixed with anti freeze. In terms of 325 00:20:44,920 --> 00:20:48,080 Speaker 1: the demon Core, for years after this incident happened, it 326 00:20:48,119 --> 00:20:50,160 Speaker 1: was believed that it was sent on to Bikini at 327 00:20:50,160 --> 00:20:54,320 Speaker 1: all for use in Operation Crossroads as planned, and while 328 00:20:54,320 --> 00:20:56,800 Speaker 1: it was described as quote a little hot but not 329 00:20:56,920 --> 00:21:00,359 Speaker 1: too hot to handle. After that second accident, it was 330 00:21:00,440 --> 00:21:03,280 Speaker 1: saved for the last detonation just in case that was 331 00:21:03,359 --> 00:21:06,879 Speaker 1: going to affect the results. That last test wound up 332 00:21:06,880 --> 00:21:10,000 Speaker 1: being canceled, and the demon Corps was later melted down 333 00:21:10,080 --> 00:21:14,560 Speaker 1: and reintegrated into the nuclear material stockpile. At some point 334 00:21:14,600 --> 00:21:18,760 Speaker 1: it was probably incorporated into other weapons. Before we move on, 335 00:21:18,880 --> 00:21:22,320 Speaker 1: we should note that there have been ongoing issues with 336 00:21:22,440 --> 00:21:26,320 Speaker 1: safety at Los Alamos National Laboratory in more recent years. 337 00:21:26,359 --> 00:21:30,560 Speaker 1: Aside from that, even plutonium photo op that we mentioned 338 00:21:30,560 --> 00:21:35,560 Speaker 1: earlier in sen it was rated does not meet expectations 339 00:21:35,560 --> 00:21:39,760 Speaker 1: in the Department of Energy Nuclear Criticality Safety Programs annual 340 00:21:39,840 --> 00:21:44,240 Speaker 1: report that was raised up to adequate but needs improvement 341 00:21:44,400 --> 00:21:48,840 Speaker 1: in eighteen and twenty nineteen. Also, that second accident with 342 00:21:48,880 --> 00:21:52,600 Speaker 1: the demon Core is dramatized in the nine film Fat 343 00:21:52,640 --> 00:21:55,960 Speaker 1: Man and Little Boy, with John Cusack as a fictionalized 344 00:21:56,000 --> 00:21:59,520 Speaker 1: Slotan who is named Michael Merriman in the film. I 345 00:21:59,600 --> 00:22:02,199 Speaker 1: watched just that scene while I was working on this, 346 00:22:02,320 --> 00:22:05,000 Speaker 1: and even knowing literally what's going to happen, I found 347 00:22:05,040 --> 00:22:13,760 Speaker 1: it very tense. Yeah, so we're gonna take a quick break. 348 00:22:18,840 --> 00:22:22,040 Speaker 1: The two incidents that we already talked about happened during 349 00:22:22,200 --> 00:22:26,919 Speaker 1: criticality experiments. The researchers were intentionally pushing the limits to 350 00:22:27,000 --> 00:22:30,520 Speaker 1: do tests and gather data. But many of the other 351 00:22:30,640 --> 00:22:35,280 Speaker 1: nuclear criticality accidents have happened while nuclear material was being 352 00:22:35,400 --> 00:22:39,480 Speaker 1: processed in some way, So these are people working at 353 00:22:39,520 --> 00:22:44,480 Speaker 1: facilities that were actively trying to avoid a criticality. However, 354 00:22:44,520 --> 00:22:46,800 Speaker 1: in a lot of cases, the workers who were actually 355 00:22:46,840 --> 00:22:51,719 Speaker 1: handling this material also were not nuclear physicists. In some cases, 356 00:22:51,760 --> 00:22:55,240 Speaker 1: they hadn't really been trained in criticality safety at all. 357 00:22:55,280 --> 00:22:58,520 Speaker 1: They didn't necessarily know that something like the size and 358 00:22:58,680 --> 00:23:02,119 Speaker 1: shape of a container could be an integral part of 359 00:23:02,160 --> 00:23:07,440 Speaker 1: preventing a disaster. For example, on March fifty three, at 360 00:23:07,440 --> 00:23:11,800 Speaker 1: the Mayac Enterprise facility in Russia, two workers were transferring 361 00:23:11,840 --> 00:23:16,239 Speaker 1: plutonium solution from one vessel to another. Vessels had been 362 00:23:16,320 --> 00:23:19,200 Speaker 1: arranged in a row along a wall, and every other 363 00:23:19,320 --> 00:23:23,440 Speaker 1: vessel was supposed to be left empty to prevent criticality. 364 00:23:23,640 --> 00:23:26,600 Speaker 1: The vessels were also supposed to contain at most five 365 00:23:26,680 --> 00:23:30,560 Speaker 1: hundred grams of plutonium, but neither of those limits was 366 00:23:30,600 --> 00:23:35,080 Speaker 1: actually being followed. Vessels contained plutonium when they weren't supposed to, 367 00:23:35,440 --> 00:23:38,560 Speaker 1: and also contained more than that five hundred grand limit, 368 00:23:39,080 --> 00:23:43,280 Speaker 1: So when a criticality occurred during the plutonium transfer, workers 369 00:23:43,520 --> 00:23:46,879 Speaker 1: not only did not know that it had happened, but 370 00:23:46,960 --> 00:23:49,080 Speaker 1: they also did not know that it had caused a 371 00:23:49,119 --> 00:23:52,320 Speaker 1: serious problem because they had not been trained on this. 372 00:23:52,880 --> 00:23:56,040 Speaker 1: They just noticed that one of the vessels became warm 373 00:23:56,160 --> 00:23:59,680 Speaker 1: to the touch, so they started removing the plutonium solution 374 00:23:59,800 --> 00:24:03,280 Speaker 1: out of it and kept on working. They only reported 375 00:24:03,320 --> 00:24:06,040 Speaker 1: the incident two days later when one of them suddenly 376 00:24:06,080 --> 00:24:09,280 Speaker 1: became ill. The worker who was closer to the vessel 377 00:24:09,320 --> 00:24:11,760 Speaker 1: when it went critical ultimately had to have both of 378 00:24:11,840 --> 00:24:15,760 Speaker 1: his legs amputated because of extreme tissue damage from this exposure. 379 00:24:16,240 --> 00:24:19,639 Speaker 1: But in some cases, the staff involved in these incidents 380 00:24:19,720 --> 00:24:22,800 Speaker 1: were trained. That was the case with Cecil Kelly, who 381 00:24:22,840 --> 00:24:26,119 Speaker 1: received a lethal radiation dose in a criticality accident at 382 00:24:26,160 --> 00:24:31,280 Speaker 1: Los Alamos on December. Kelly had more than a decade 383 00:24:31,280 --> 00:24:34,240 Speaker 1: of experience, but the tank he was working with had 384 00:24:34,280 --> 00:24:37,680 Speaker 1: a concentration of plutonium that was more than two hundred 385 00:24:37,680 --> 00:24:40,240 Speaker 1: times when it should have been. For reasons that are 386 00:24:40,280 --> 00:24:45,000 Speaker 1: not entirely clear. This happened during a physical inventory when 387 00:24:45,040 --> 00:24:49,280 Speaker 1: liquids from two holding vessels were moved into one larger vessel. 388 00:24:49,320 --> 00:24:52,320 Speaker 1: So Kelly was standing on a small ladder to see 389 00:24:52,359 --> 00:24:54,960 Speaker 1: into a viewing window on a tank that was being 390 00:24:55,040 --> 00:24:59,400 Speaker 1: used to chemically separate plutonium from other compounds, and when 391 00:24:59,400 --> 00:25:03,479 Speaker 1: he turned the stir on inside the tank, the shape 392 00:25:03,480 --> 00:25:07,280 Speaker 1: of the plutonium layer inside this solution allowed it to 393 00:25:07,280 --> 00:25:11,120 Speaker 1: go critical. The radiation dosed to his upper body has 394 00:25:11,160 --> 00:25:15,200 Speaker 1: been estimated at a hundred and twenty gray. Kelly either 395 00:25:15,359 --> 00:25:19,159 Speaker 1: fell or was knocked to the floor and was completely disoriented. 396 00:25:19,200 --> 00:25:23,199 Speaker 1: After the criticality. He kept saying I'm burning up, and 397 00:25:23,320 --> 00:25:25,920 Speaker 1: his colleagues and a nurse who arrived thought he had 398 00:25:25,920 --> 00:25:29,680 Speaker 1: sustained some kind of a chemical burn. The nurse even 399 00:25:29,720 --> 00:25:33,520 Speaker 1: commented that he had nice pink skin. This was actually 400 00:25:33,520 --> 00:25:36,840 Speaker 1: a sign of radiation exposure, like a mild sunburn, and 401 00:25:36,920 --> 00:25:40,359 Speaker 1: not a sign of being in good health. Yeah, because 402 00:25:40,359 --> 00:25:43,199 Speaker 1: of all of the all of the safety measures and 403 00:25:43,280 --> 00:25:45,800 Speaker 1: his training and all this other stuff. Like his colleagues, 404 00:25:46,080 --> 00:25:48,040 Speaker 1: it was like it took a while for them to 405 00:25:48,080 --> 00:25:51,199 Speaker 1: be like, did a criticality happen and we didn't realize it. 406 00:25:52,160 --> 00:25:55,520 Speaker 1: Kelly died thirty five hours after his exposure, and his 407 00:25:55,640 --> 00:26:00,880 Speaker 1: death actually sparked the human tissue analysis project at Salamos. 408 00:26:01,160 --> 00:26:04,679 Speaker 1: They would keep tissue samples for further study, and that 409 00:26:04,720 --> 00:26:09,000 Speaker 1: actually led to a lawsuit. Kelly's family had authorized an 410 00:26:09,040 --> 00:26:12,640 Speaker 1: autopsy to determine his cause of death, but they did 411 00:26:12,680 --> 00:26:16,359 Speaker 1: not imagine that that was going to include tissue samples 412 00:26:16,400 --> 00:26:21,000 Speaker 1: being retained for further study through this program. Other criticality 413 00:26:21,040 --> 00:26:24,920 Speaker 1: accidents during the nineteen fifties and sixties stemmed from workers 414 00:26:25,000 --> 00:26:29,719 Speaker 1: intentionally bypassing safeguards meant to prevent them. One such accident 415 00:26:29,760 --> 00:26:33,520 Speaker 1: happened on July nineteen sixty four at a facility that 416 00:26:33,640 --> 00:26:37,600 Speaker 1: recovered uranium from scrap metal in Wood River Junction, Rhode Island. 417 00:26:38,400 --> 00:26:41,640 Speaker 1: This facility had been in operation for about four months 418 00:26:41,720 --> 00:26:45,720 Speaker 1: and part of the process involved workers manually shaking eleven 419 00:26:45,840 --> 00:26:50,280 Speaker 1: leader bottles full of contaminated solvent. This was a tedious 420 00:26:50,320 --> 00:26:53,960 Speaker 1: process that no one particularly enjoyed, so a worker had 421 00:26:54,000 --> 00:26:57,480 Speaker 1: the idea to combine the contents of several eleven liter 422 00:26:57,600 --> 00:27:00,800 Speaker 1: bottles into a large tank and to use a stir 423 00:27:01,760 --> 00:27:06,080 Speaker 1: running Concurrently with that decision, one of the plants evaporators 424 00:27:06,080 --> 00:27:09,159 Speaker 1: had not been working properly, and it turned out that 425 00:27:09,200 --> 00:27:12,439 Speaker 1: this was because it was plugged with uranal nitrate crystals, 426 00:27:12,520 --> 00:27:17,679 Speaker 1: that is, a uranium salt. Fixing that problem involved filling 427 00:27:17,800 --> 00:27:22,600 Speaker 1: several bottles with a concentrated grail nitrate solution. As that 428 00:27:22,640 --> 00:27:27,520 Speaker 1: plug was dissolved and removed. Even though those bottles were labeled, 429 00:27:27,640 --> 00:27:31,920 Speaker 1: someone mistook them for the ones that contained the contaminated solvent, 430 00:27:32,040 --> 00:27:35,320 Speaker 1: which was being mixed in the large tank. When the 431 00:27:35,400 --> 00:27:39,359 Speaker 1: concentrated urinal nitrate solution was dumped into the tank, it 432 00:27:39,400 --> 00:27:43,119 Speaker 1: went critical, causing a blue white flash of light and 433 00:27:43,160 --> 00:27:46,320 Speaker 1: splashing liquid up and out of the tank and directly 434 00:27:46,400 --> 00:27:50,240 Speaker 1: onto the worker. The criticality alarm sounded and the worker 435 00:27:50,359 --> 00:27:54,400 Speaker 1: ran to a nearby emergency shack. A supervisor who came 436 00:27:54,400 --> 00:27:57,000 Speaker 1: in to investigate turned off the stir in the tank, 437 00:27:57,320 --> 00:28:00,920 Speaker 1: which caused a second criticality as the solution change shape, 438 00:28:01,320 --> 00:28:03,679 Speaker 1: But no one knew about the second criticality at the 439 00:28:03,720 --> 00:28:06,280 Speaker 1: time because the alarm was still going off from the 440 00:28:06,320 --> 00:28:11,199 Speaker 1: first one. Yet there were multiple multiple failures in the 441 00:28:11,320 --> 00:28:16,320 Speaker 1: process and the safety measures that were involved in this incident. 442 00:28:17,119 --> 00:28:20,080 Speaker 1: The technician who had been working the tank during that 443 00:28:20,119 --> 00:28:24,399 Speaker 1: first criticality died of acute radiation exposure two days later 444 00:28:24,720 --> 00:28:28,320 Speaker 1: after a radiation dose of about a hundred gray. The 445 00:28:28,359 --> 00:28:33,240 Speaker 1: supervisor's dose was somewhere around one gray. Other people nearby 446 00:28:33,280 --> 00:28:37,360 Speaker 1: were also exposed to lesser doses as well. A similar 447 00:28:37,400 --> 00:28:40,880 Speaker 1: incident took place at the MAAC Enterprise facility. On January 448 00:28:40,920 --> 00:28:45,920 Speaker 1: sco workers decided to drain a tank that had been 449 00:28:46,000 --> 00:28:50,040 Speaker 1: used to hold material from criticality experiments faster than it 450 00:28:50,080 --> 00:28:53,400 Speaker 1: was designed to drain. They removed the bolts that were 451 00:28:53,400 --> 00:28:55,840 Speaker 1: holding the tank to the structure and tipped it over 452 00:28:55,920 --> 00:28:59,640 Speaker 1: to drain it into containers. The shape of the material 453 00:29:00,000 --> 00:29:03,720 Speaker 1: created in this process allowed a criticality, which ejected a 454 00:29:03,800 --> 00:29:07,240 Speaker 1: huge amount of material from the tank. Three of the 455 00:29:07,280 --> 00:29:10,080 Speaker 1: four people who were doing this task died as a result, 456 00:29:10,440 --> 00:29:12,840 Speaker 1: and the fourth, who was about three meters away at 457 00:29:12,880 --> 00:29:15,640 Speaker 1: the time, was blinded and had long term damage to 458 00:29:15,680 --> 00:29:18,720 Speaker 1: the systems and organs on the left side of her body, 459 00:29:18,800 --> 00:29:21,880 Speaker 1: which was closer to the tank when it went critical. Yeah. 460 00:29:21,920 --> 00:29:25,360 Speaker 1: I took notes on so many other incidents as I 461 00:29:25,440 --> 00:29:29,520 Speaker 1: was working on this, and it's really like almost the 462 00:29:29,560 --> 00:29:32,240 Speaker 1: same story over and over and over. A lot of 463 00:29:32,280 --> 00:29:38,360 Speaker 1: it involves containers of the wrong size or shape being 464 00:29:38,480 --> 00:29:41,480 Speaker 1: used when they should not have been. So the good 465 00:29:41,480 --> 00:29:46,360 Speaker 1: news is criticality accidents like this are far less common 466 00:29:46,400 --> 00:29:49,760 Speaker 1: today than they were during the nineteen fifties and sixties. 467 00:29:50,240 --> 00:29:51,880 Speaker 1: Some of this is thanks to the end of the 468 00:29:51,920 --> 00:29:55,840 Speaker 1: Cold War, so the rush to develop and produce nuclear weapons. 469 00:29:55,920 --> 00:29:58,960 Speaker 1: Meant the United States and the Soviet Union in particular, 470 00:29:59,040 --> 00:30:01,560 Speaker 1: had a lot of facilities that were working with these 471 00:30:01,600 --> 00:30:06,400 Speaker 1: kinds of materials. As we noted earlier, the accumulation of 472 00:30:06,560 --> 00:30:10,120 Speaker 1: enough material to even be able to cause a criticality 473 00:30:10,160 --> 00:30:13,440 Speaker 1: and an understanding of what it took to prevent a criticality, 474 00:30:13,520 --> 00:30:17,040 Speaker 1: those two things were happening in tandem. In some cases, 475 00:30:17,080 --> 00:30:21,000 Speaker 1: these facilities are basically working out safety standards as they went, 476 00:30:21,480 --> 00:30:24,960 Speaker 1: and others though they were disregarding safety standards in order 477 00:30:25,000 --> 00:30:28,320 Speaker 1: to get work done faster or march cheaply. But it's 478 00:30:28,320 --> 00:30:32,560 Speaker 1: also because as these incidents happened, the governments and facilities 479 00:30:32,600 --> 00:30:36,400 Speaker 1: involved got better at designing procedures and protocols to prevent 480 00:30:36,440 --> 00:30:39,560 Speaker 1: them in the future, like instead of having a line 481 00:30:39,560 --> 00:30:42,240 Speaker 1: of containers half of which were meant to be left empty, 482 00:30:42,880 --> 00:30:45,840 Speaker 1: just not having containers arranged in a way that a 483 00:30:45,880 --> 00:30:50,760 Speaker 1: criticality could ever result, or not allowing containers with geometry 484 00:30:50,800 --> 00:30:53,880 Speaker 1: that could allow a criticality into the facility at all. 485 00:30:55,000 --> 00:30:58,000 Speaker 1: As a result, when it comes to criticality accidents during 486 00:30:58,040 --> 00:31:01,720 Speaker 1: processing and handling, the world has gone from multiple fatal 487 00:31:01,760 --> 00:31:05,840 Speaker 1: accidents every year to fewer than one per decade. The 488 00:31:05,920 --> 00:31:08,800 Speaker 1: other side of that progression, though, is that when criticality 489 00:31:08,840 --> 00:31:12,240 Speaker 1: accidents have happened since then, a lot of times they've 490 00:31:12,240 --> 00:31:16,760 Speaker 1: been just totally unexpected. In there was a criticality at 491 00:31:16,800 --> 00:31:20,000 Speaker 1: the fuel conversion test building at the j c O 492 00:31:20,120 --> 00:31:26,040 Speaker 1: Fabrication Plant Company site and Tokamura, Japan. Workers were using 493 00:31:26,040 --> 00:31:30,360 Speaker 1: containers with unfavorable geometry because the ones they were supposed 494 00:31:30,400 --> 00:31:33,720 Speaker 1: to be using were more difficult to fill, and the 495 00:31:33,800 --> 00:31:37,760 Speaker 1: criticality accident that resulted from this was ongoing, with criticalities 496 00:31:37,880 --> 00:31:41,440 Speaker 1: recurring over the course of twenty hours. Two are the 497 00:31:41,480 --> 00:31:44,720 Speaker 1: three workers who were nearby when it started. Died when 498 00:31:44,840 --> 00:31:49,880 Speaker 1: radiation was released into surrounding neighborhoods around the plant. Although 499 00:31:49,920 --> 00:31:54,160 Speaker 1: this incident was similar to earlier ones in that workers 500 00:31:54,160 --> 00:31:57,480 Speaker 1: had been using the wrong containers to make their jobs easier, 501 00:31:58,000 --> 00:32:01,320 Speaker 1: it was also really an outlier. There were so many 502 00:32:01,400 --> 00:32:04,440 Speaker 1: procedures and standards in place at the facility that people 503 00:32:04,520 --> 00:32:08,480 Speaker 1: didn't think of criticality was even possible there. Because of 504 00:32:08,520 --> 00:32:12,280 Speaker 1: this belief, there weren't even criticality alarms at the facility. 505 00:32:12,400 --> 00:32:17,360 Speaker 1: The censors that reported something amiss we're gamma detectors. Yeah, 506 00:32:17,600 --> 00:32:22,280 Speaker 1: So if we're gonna have to have nuclear facilities doing 507 00:32:22,880 --> 00:32:27,000 Speaker 1: such work. Uh, the good news is we're better at 508 00:32:27,000 --> 00:32:30,800 Speaker 1: it now, Golfully, as I was working on this and 509 00:32:30,840 --> 00:32:32,960 Speaker 1: I was going through all of these, um, all of 510 00:32:32,960 --> 00:32:35,720 Speaker 1: these criticality incidents, I got to this point where I 511 00:32:35,760 --> 00:32:41,959 Speaker 1: was like, man, what what's an outcome that can be here? 512 00:32:42,000 --> 00:32:46,840 Speaker 1: Because just having one after another of these incidents wasn't 513 00:32:46,880 --> 00:32:50,480 Speaker 1: just incredibly grim And it really is like if you 514 00:32:50,560 --> 00:32:54,080 Speaker 1: look at sort of a timeline, it goes from just 515 00:32:54,240 --> 00:32:58,040 Speaker 1: a block of multiple every year through the fifties and 516 00:32:58,080 --> 00:33:00,200 Speaker 1: sixties too, Like we get to the seventies and it's 517 00:33:00,240 --> 00:33:04,400 Speaker 1: like one and then a whole long time and then one. 518 00:33:05,720 --> 00:33:10,840 Speaker 1: So fingers crossed, we are passed this as a society 519 00:33:10,880 --> 00:33:18,280 Speaker 1: and a global world culture. Shure. Yeah, I have so 520 00:33:18,320 --> 00:33:21,000 Speaker 1: many questions. We can discuss them in our Friday episode. 521 00:33:22,040 --> 00:33:25,160 Speaker 1: In the meantime, do you have listener mail? I knew 522 00:33:25,240 --> 00:33:29,360 Speaker 1: it's from Rachel and the title was Nina O Taro 523 00:33:29,480 --> 00:33:32,560 Speaker 1: Warren in real life, and I was like, oh, all right, 524 00:33:32,760 --> 00:33:36,600 Speaker 1: I'm curious about this email. Um So, Rachel talks about 525 00:33:36,640 --> 00:33:40,280 Speaker 1: living in Gwynette County, Georgia, so right outside of Atlanta, 526 00:33:40,880 --> 00:33:45,880 Speaker 1: super close to our our headquarters. And our recent episode 527 00:33:45,880 --> 00:33:50,000 Speaker 1: on nina O Taro Warren and her voting efforts. Basically, 528 00:33:50,280 --> 00:33:53,160 Speaker 1: Rachel had tried to figure out where her mail in 529 00:33:53,280 --> 00:33:57,440 Speaker 1: ballot was for the election because it had not arrived yet, 530 00:33:57,480 --> 00:34:01,520 Speaker 1: and Rachel says quote worried, contacted my local League of 531 00:34:01,560 --> 00:34:05,000 Speaker 1: Women Voters for more info and learned that Gwynette County 532 00:34:05,080 --> 00:34:07,840 Speaker 1: is the only county in Georgia that's required to provide 533 00:34:07,880 --> 00:34:11,680 Speaker 1: election materials in both English and Spanish. Because of this 534 00:34:11,840 --> 00:34:15,040 Speaker 1: and a recent lawsuit, the envelopes are larger than normal 535 00:34:15,160 --> 00:34:17,360 Speaker 1: and are sent to a special printer. But not to worry. 536 00:34:17,680 --> 00:34:20,040 Speaker 1: My ballot is on the way and will arrive soon. 537 00:34:20,360 --> 00:34:23,680 Speaker 1: It's just taking its time. Rachel then links to an 538 00:34:23,800 --> 00:34:28,600 Speaker 1: article in the Atlanta Journal Constitution about um like this 539 00:34:28,680 --> 00:34:32,400 Speaker 1: whole why why it's taking longer for Gwennette County ballots. 540 00:34:33,239 --> 00:34:35,440 Speaker 1: It wasn't until I heard the episode about Otaro Warren 541 00:34:35,480 --> 00:34:38,640 Speaker 1: that I learned why my county requires bi lingual materials. 542 00:34:38,640 --> 00:34:40,879 Speaker 1: So it's very excited to learn this history about something 543 00:34:40,920 --> 00:34:43,399 Speaker 1: that is currently affecting my life, and to learn about 544 00:34:43,400 --> 00:34:45,400 Speaker 1: such an amazing woman. Keep up the great work, Rachel, 545 00:34:45,440 --> 00:34:48,680 Speaker 1: Thank you so much. Rachel, I did not know that 546 00:34:48,800 --> 00:34:52,600 Speaker 1: Gwynette County was one of the places where there need 547 00:34:52,680 --> 00:34:56,400 Speaker 1: to be voting materials printed in Spanish. In uh, most 548 00:34:56,480 --> 00:35:00,200 Speaker 1: of the things that you read that are about that 549 00:35:00,280 --> 00:35:03,960 Speaker 1: particular issue with the with like the language Minority amendments 550 00:35:04,000 --> 00:35:07,640 Speaker 1: to the Voting Rights Act. They talk a lot about, um, 551 00:35:07,680 --> 00:35:10,399 Speaker 1: New Mexico and Texas and places that have a large 552 00:35:10,400 --> 00:35:14,279 Speaker 1: indigenous population. UM. And I didn't realize that the uh 553 00:35:14,880 --> 00:35:18,640 Speaker 1: that there were communities in Georgia not that far from 554 00:35:18,640 --> 00:35:21,439 Speaker 1: where I used to live that actually met that threshold. UM. 555 00:35:21,480 --> 00:35:23,640 Speaker 1: I of course knew there were lots of Spanish speakers 556 00:35:24,040 --> 00:35:26,759 Speaker 1: in Gwynette County, but not to the point of like 557 00:35:26,840 --> 00:35:30,640 Speaker 1: triggering that uh, that part of the Voting Rights Act amendments. 558 00:35:30,719 --> 00:35:34,359 Speaker 1: So thank you Rachel for getting a touch about that. 559 00:35:34,960 --> 00:35:37,120 Speaker 1: If you would like to write to us about this 560 00:35:37,239 --> 00:35:40,200 Speaker 1: or any other podcast or history podcast that I Heart 561 00:35:40,280 --> 00:35:43,319 Speaker 1: radio dot com and we're all over social media at 562 00:35:43,400 --> 00:35:47,000 Speaker 1: mss in History. UH. That's where you'll find our Facebook, Pinterest, Twitter, 563 00:35:47,040 --> 00:35:49,560 Speaker 1: and Instagram, and you can subscribe to our show on 564 00:35:49,680 --> 00:35:52,320 Speaker 1: the I Heart Radio app and Apple podcast and anywhere 565 00:35:52,360 --> 00:35:59,919 Speaker 1: else you get your podcasts. Stuff you Missed in History 566 00:36:00,040 --> 00:36:02,680 Speaker 1: LASS is a production of I heart Radio. For more 567 00:36:02,760 --> 00:36:05,799 Speaker 1: podcasts from I heart Radio, visit the I heart Radio app, 568 00:36:05,880 --> 00:36:09,080 Speaker 1: Apple Podcasts, or wherever you listen to your favorite shows. 569 00:36:09,960 --> 00:36:10,000 Speaker 1: H