The 10 Scariest American Nuclear Incidents

THE DEMON CORE

The first American to die as a result of nuclear testing (not counting whatever gophers and scorpions that were living too close to the test site) was physicist Harry Daghlian. Because nuclear physics was actually pretty simple at the time, Daghlian was building a neutron reflector by just stacking bricks of tungsten carbide around a spherical plutonium core when he accidentally dropped a brick right on top of the core, causing a supercritical power excursion-a complicated way of saying that Harry got zapped with a lethal amount of radiation, leading to his death a month after the bombing of Hiroshima.

The same core was involved in another criticality accident involving Canadian physicist Louis Slotin, who was much more vocal than Daghlian about how the dangers of radiation and criticality accidents were exaggerated and overstated and subsequently died a week after his exposure to radioactivity in hideous and unimaginable pain. Oddly superstitious scientists nicknamed the plutonium sphere the "Demon Core" and blew it up as part of the Crossroads nuclear weapons tests.

THREE MILE ISLAND

The worst accident in the history of American commercial nuclear power, the Three Mile Island incident either resulted in dozens of deaths or didn't hurt anybody at all. The established facts are that a critical steam valve jammed open and a combination of poorly trained workers and poorly designed control panels lead to the release of radioactive noble gases and iodides into the surrounding area.

Multiple government investigations including one led by then-President Jimmy Carter (who, as a former Navy submarine reactor technician, may have been the only elected official actually qualified to investigate a nuclear accident) established that plant owners Babcock & Wilcox had been cutting corners for years and that the Nuclear Regulatory Commission had failed to enforce important safety rules, but medical investigations of the aftermath of TMI became completely politicized, leading to results that ranged from nearly two hundred radiation-related deaths to absolutely zero unusual deaths at all depending on who was funding the survey.

Whatever the real effects of the Three Mile Island accident, it ultimately killed the American nuclear power industry, delaying or cancelling the construction of virtually all power plants in the country.

THE IDAHO FALLS EXCURSION

Part of a US Army initiative to develop a cheap, small, efficient reactor, the Stationary Low-Power Reactor Number One (or much less of a mouthful, SL-1) was intended to power remote radar stations in the Arctic Circle.

Sadly, the SL-1's development at Idaho Falls was halted when workers abruptly yanked out a central control rod that was supposed to be withdrawn gently, leading to an immediate and lethal criticality excursion that irradiated the three men so severely that they had to be buried in lead-lined coffins. The incident was the first known fatality directly related to a nuclear reaction.

USS SEAWOLF

The second of the Navy's nuclear submarines following the Nautilus, the Seawolf also carried the Navy's first and only superheated steam power plant. This resulted in a quieter, smaller, and overall more efficient reactor design, but one subject to additional safety issues, resulting in the Seawolf's unofficial nickname "Blue Haze."

Eventually the Navy gave up on the superheated reactor design and replaced it with a conventional unit in 1960, disposing of the still-active reactor by sealing it in a steel container and... randomly dumping it in the ocean some 120 miles from the coast of Maryland. When government officials gently suggested some twenty years later that maybe someone should check up on the reactor, the Navy was unable to find it again, but they are fairly sure that it's okay.

PROJECT 57

Heinz' ultimate attempt to design a ketchup for the atomic age? Nope, Project 57 was actually the government's attempt to simulate the release of plutonium from a plane crash or other situations where a nuclear weapon might partially explode (e.g. that the conventional explosives go off, but not enough of them to trigger the atomic reaction).

Mock cities were built in the Nevada Desert and populated with dogs, rats, sheep, and burros before a spare nuke was deliberately misfired in a way consistent with a plane wreck. The experiment provided extremely valuable information on how radioactive material would propagate after a subcritical accident... and also turned out to have polluted the groundwater and earthworms, spreading said material further than the scientists predicted.

OPERATION MORNING LIGHT

The Soviet Union's oddly carefree attitude towards nuclear safety meant that while American satellites were typically powered by solar wings or radio-thermal generators (a radioactive heat source that was more like a nuclear battery than a reactor) the Russians sent up over thirty satellites with miniature nuclear reactors on board.

As it happened, not all of these satellites stayed where they were supposed to, and one went so badly off course that the Soviets sheepishly informed NORAD that the radioactive spy satellite Kosmos 954 and its attached nuclear reactor was going to slam into some yet-to-be-determined part of North America.

Thankfully, Kosmos chose a desolate section of Canada to collide with, spreading debris over a 370-mile swath through the Northwest Territories. Soviet scientists claimed that the satellite had been entirely destroyed during reentry, a claim they later had to retract when the huge American-Canadian search effort started turning up inconveniently large and radioactive chunks of metal along the debris path. The USSR eventually coughed up three million dollars Canadian for damages and instituted a more comprehensive system of backups in its core ejection systems.

CODE NAME KIWI

While most of NASA was determined to make it to the moon with conventional chemical rockets, a parallel program was under way to design a power system capable of reaching Mars and incidentally irradiating everything in its path. Nuclear Engine Rocket Vehicle Application (or NERVA) took many prototype forms, but virtually all the designs involved radioactive exhaust and a high risk of explosion.

In perhaps the first sensible and cautious move made since the beginning of the NERVA program, physicists reasoned that one of the test engines (known as Kiwi) should be deliberately blown up in a controlled explosion.

As it turned out, the controlled explosion got a teeny bit out of hand, throwing a 100-lb chunk of nuclear fuel a quarter mile from the test site, shooting a multicolored plume of radioactive smoke almost three miles in the air (whence it eventually drifted over Los Angeles) and very likely violating the Limited Test Ban Treaty. The results of the test and the exposure levels for the personnel involved (and for the Angelenos) remain classified.

THE BOMBING OF GOLDSBORO

Only four years after the government attempted to study the danger of radioactive release from a crashed nuclear weapon, they almost had an opportunity to test it. In 1961, a B-52 with two armed nuclear bombs reported a critical fuel leak shortly before breaking up over the town of Goldsboro, North Carolina.

For some reason, five of the six safety systems intended to prevent one of the bombs from going off were disabled, and investigators believe the only reason that Goldsboro still exists today was that the final arming switch on the pilot's console was never flipped. Ironically, that bombs being in an almost-active state may have prevented them from hitting the ground hard enough to crack open-the radar fuzing was active and deployed the parachute that would normally just ensure that the bomb would go off at the ideal height.

The other bomb hit the ground so hard it disintegrated, and while the plutonium and tritium were recovered, the excavation site became so flooded with groundwater that the Army Corps of Engineers simply gave up and bought a circular plot of land around the bomb some four hundred feet in diameter. Had either bomb gone off, an explosion more than 250 times more powerful than the Hiroshima bombing would quite possibly have carved a new bay out of the North Carolina coast.

OPERATION ARGUS

A risky exoatmospheric nuclear detonation that was rushed into production before the various atmospheric test ban treaties could be finalized, Operation Argus was meant to test the idea that an artificial radiation belt could be created that would disrupt or destroy the electronics aboard incoming Soviet ICBMs and satellites.

Argus also proved that it was possible to fire nuclear missiles from ships, a result that the Navy was quick to publicize. At any rate, the radiation belt that was briefly generated was seen as a point in favor of the theory, but also an indication that larger warheads would be needed to have the desired effect and there was likely no way to make further tests in the time remaining.