Three Mile Island accident

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conducted studies. The approximately 2 million people around TMI-2 during the accident are estimated to have received an average radiation dose of only about 1 millirem above the usual background dose. To put this into context, exposure from a chest X-ray is about 6 millirem and the area's natural radioactive background dose is about 100–125 millirem per year for the area. The accident's maximum dose to a person at the site boundary would have been less than 100 milligrams above the background. In the months following the accident, although questions were raised about possible adverse effects from radiation on human, animal, and plant life in the TMI area, none could be directly correlated to the accident. Thousands of environmental samples of air, water, milk, vegetation, soil, and foodstuffs were collected by various government agencies monitoring the area. Very low levels of radionuclides could be attributed to releases from the accident. Comprehensive investigations and assessments by several well-respected organizations, such as Columbia University and the University of Pittsburgh, have concluded that in spite of serious damage to the reactor, the actual release had negligible effects on the physical health of individuals or the environment.

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showing water level in the pressurizer. (In this Babcock & Wilcox reactor, there is no instrument for measuring, as a gas gauge does in an automobile, the amount of fluid in the reactor core portion of the coolant loop—or, stated more simply, the depth of water around the fuel rods.) If the pressurizer level remains high, the operators are not trained to anticipate that coolant water may be leaking out of the primary system. Indeed, the operator training at Met Ed, at B&W, even back in the navy, tells these men that the condition to avoid at all costs is 'going solid'—permitting the pressurizer to fill with water and thus losing the ability to regulate system pressure through the control of the pressurizer steam bubble. The training and the written emergency procedures of the operators never postulated a loss-of-coolant accident through the top of the pressurizer itself, as is happening now. With the relief valve stuck open, the steam bubble vanishes like a jinni out through the valve, and the coolant water right after it. The system pressure continues to be low—a sign of a loss-of-coolant accident. But the pressurizer water level indicator keeps getting higher. Why is this?

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override the emergency system and sharply reduce flow from the HPI pumps. It is a human intervention in the automatic chain of events not inconsistent with the operators' training, but it will have awesome consequences. At Zewe's direction, Operator Ed Frederick shuts down one HPI pump and throttles back the other one from a maximum of 400 gallons per minute (gpm) to about half that flow. Not only does he throttle HPI, Frederick also lifts the plug at the bottom of the reactor coolant system to maximize "letdown" through the normal "makeup and letdown system" that, like a swimming pool filtration system, constantly works to purify primary reactor coolant water. The effect of these two actions is to reduce to a trickle the amount of water being added to the system. This miserly flow rate, perhaps 25 gpm, will continue for the better part of the next 3 hours and is more than offset by the amount of coolant lost every minute through the stuck-open PORV.

754:, Met Ed, General Public Utilities, and the NRC for lapses in quality assurance and maintenance, inadequate operator training, lack of communication of important safety information, poor management, and complacency, but avoided drawing conclusions about the future of the nuclear industry. The heaviest criticism from the Kemeny Commission said that "... fundamental changes will be necessary in the organization, procedures, and practices—and above all—in the attitudes" of the NRC and the nuclear industry. Kemeny said that the actions taken by the operators were "inappropriate" but that the workers "were operating under procedures that they were required to follow, and our review and study of those indicates that the procedures were inadequate" and that the control room "was greatly inadequate for managing an accident". 4576:

iodine-131. A curie is a unit of measurement formerly used to indicate the decay rate (or level of activity) of radioactive substances. Of the estimated 64 million curies of iodine-131 in the core at the time of the accident, less than 20 curies leaked to the atmosphere. This was a far smaller release of iodine-131 than reactor experts had postulated in projecting the consequences of a severe reactor accident before Three Mile Island. Researchers found that most of the iodine-131 in the core had combined with other elements to form compounds that dissolved in water or had attached to metal surfaces in the containment building. Under the conditions in the core and the reactor building, the iodine did not remain in a gaseous state long enough to escape from the plant into the environment.

729:, a former nuclear industry executive and anti-nuclear advocate, said "I think the numbers on the NRC's website are off by a factor of 100 to 1,000". Gundersen offers evidence, based on pressure monitoring data, for a hydrogen explosion shortly before 2:00 p.m. on March 28, 1979, which would have provided the means for a high dose of radiation to occur. Gundersen cites affidavits from four reactor operators according to which the plant manager was aware of a dramatic pressure spike, after which the internal pressure dropped to outside pressure. Gundersen also claimed that the control room shook and doors were blown off hinges. However, official NRC reports refer merely to a "hydrogen burn". 806: 1153: 4974:"nuclear power is inherently too dangerous to permit it to continue and expand" or that "the nation should move forward aggressively to develop additional commercial nuclear power." Rather, the commission suggested "that if the country wishes, for larger reasons, to confront the risks that are inherently associated with nuclear power, fundamental changes are necessary if those risks are to be kept within tolerable limits." It maintained that critical improvements in reactor safety required major revisions, if not a revolution, in organization, practices, procedures, and above all, the "mindset" of the nuclear industry and the NRC. 373:(LOCA). Expected symptoms for a LOCA were drops in both RCS pressure and pressurizer level. The operators' training and plant procedures did not cover a situation where the two parameters went in opposite directions. The water level in the pressurizer was rising because the steam in the space at the top of the pressurizer was being vented through the stuck-open PORV, lowering the pressure in the pressurizer because of the lost inventory. The lowering of pressure in the pressurizer made water from the coolant loop surge in and created a steam bubble in the reactor pressure vessel head, aided by the decay heat from the fuel. 4497:

Accident at Three Mile Island. In a speech to the nation about energy policies on April 5, 1979, President Carter announced that he would create an independent commission "to investigate the causes" of Three Mile Island and "to make recommendations on how to improve the safety of nuclear power plants." Six days later he formally established the commission and identified eleven persons he had appointed to it (a twelfth was added a short time later). The projected cost of the study was about $ 1 million. The White House deliberately avoided placing anyone on the panel who was associated with strong pro- or antinuclear views.

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coolant system. At full power the pressurizer contains 60% of its volume full of water. Changes in pressurizer water level are usually the result of water density changes caused by changes in average coolant temperature… A system called the… Makeup and Purification System controls the water level in the pressurizer… Water is injected into the primary coolant system to increase the pressurizer water level to the set point. A let down flow system decreases the water level… (other functions) are water purification using filters and demineralizers and controlling soluble poison concentration by adding or removing boric acid.

2869:(v) A 1978 revision in the TMI-2 surveillance procedure for the emergency feedwater block valves violated TMI-2's technical specifications, but no one realized it at the time. The approval of the revision in the surveillance procedure was not done according to Met Ed's own administrative procedures. <vi/>Performance of surveillance tests was not adequately verified to be sure that the procedures were followed correctly. On the day of the accident, emergency feedwater block valves which should have been open were closed. They may have been left closed during a surveillance test 2 days earlier. 1145: 434: 2685:

relief valves enters the tank through sparger nozzles and is condensed by water contained in the tank. Should the safety valves lift, 1,400,000 lb/hr of saturated steam at 490 psig would be discharged into the manifold of the tank. The steam flow in the tank is assumed to last 15 seconds. Peak pressure and temperature in the tank (outside the sparger manifold) would occur at the end of the steam blowdown and would be 30 psig and 200°F. Overpressure protection for the RCDT is provided by a relief valve with a setpoint of 90 psig and a rupture disc with a 100-psig setting.

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permitting the valve to shut, the light goes off. Unfortunately, the light is proof only that power is reaching the valve-opening mechanism; it is only circumstantial evidence of the actual state of the valve itself, i.e., power has been cut off from the solenoid now, and the light shows it—but the valve remains open. It is ironic, in a day that will be marked by repeated refusal of the operators and supervisors to believe ominous readings from the reactor-monitoring instruments, that they elect to be misled by this bearer of what they perceived to be good tidings.

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radioactivity" within the plant's boundaries. It required evacuation of the affected buildings, closure of the gates leading to the plant, and notification of the NRC and the state of Pennsylvania. Less than half an hour later..., the Three Mile Island station manager, declared a general emergency... New and alarmingly high radiation readings in the containment building persuaded him to announce a general emergency, which was defined as having the "potential for serious radiological consequences to the health and safety of the general public."

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medical, commercial and industrial activities contribute roughly 310 mrem more to our annual exposure. Among the largest of these sources is a computed tomography scan, which accounts for about 150 mrem. Other medical procedures make up another 150 mrem or so each year. Some consumer products such as tobacco, fertilizer, welding rods, exit signs, luminous watch dials and smoke detectors contribute about 10 mrem per year. The pie chart (on the page) shows the sources that make up the average annual U.S. radiation dose of 620 mrem.

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shipping 150 short tons (140 t) of radioactive wreckage to Idaho for storage at the Department of Energy's National Engineering Laboratory. However, the contaminated cooling water that leaked into the containment building had seeped into the building's concrete, leaving the radioactive residue too impractical to remove. Accordingly, further cleanup efforts were deferred to allow for decay of the radiation levels and to take advantage of the potential economic benefits of retiring both Unit 1 and Unit 2 together.

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per square inch, 100 psi more than normal. Then a valve atop the pressurizer, called a pilot-operated relief valve, or PORV, opened – as it was designed to do – and steam and water began flowing out of the reactor coolant system through a drain pipe to a tank on the floor of the containment building. Pressure continued to rise, however, and 8 seconds after the first pump tripped, TMI-2's reactor – as it was designed to do – scrammed: its control rods automatically dropped down into the reactor core to halt its nuclear fission.

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radioiodines were released. These releases resulted in an average dose of 1.4 mrem to the approximately two million people in the site area. This average dose is less than 1 % of the annual dose from both natural background radiation and medical practice. The 1.4-mrem dose may also be compared to differences in annual doses in background radiation from living in a brick versus a frame house, an additional 14 mrem/yr; or living in the high altitude of Denver rather than in Harrisburg, an additional 80 mrem/yr.

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technical issues, the roles of the NRC and Met Ed, emergency preparedness, public information, and health effects. After holding a series of public hearings, taking more than 150 depositions, and collecting about three hundred cubic feet of documents, it presented its findings to Carter on October 30, 1979, and released them to the public the following day. The completed study consisted of a 179-page overview and nine volumes of task force reports that totaled more than 2,200 pages.

855: 3726:...Scranton held his second news conference of the day... "At this point, we believe there is still no danger to public health." Scranton's statements left no doubt that the state had written off the utility as a partner in responding to the accident. The state hoped that it would realize greater benefits in its efforts to guard public health by collaborating with the NRC. As Critchlow recalled, "I think we just almost instinctively preferred to deal with NRC people." 2614:

Because of the contact between steam and liquid water, the water is also at the saturation temperature at steady state. Spray of cooler water enters from the top and electrical heaters at the bottom heat the liquid water. The steady state can be disturbed by water inflow or outflow, changes in inlet water temperature, changes in spray flow or changes in heater power. A PWR pressurizer control system can alter the pressure by modulating heater power and/or spray flow.

10105: 8839: 3384:(1) (Operators)... will dismiss two warnings from a temperature instrument showing relief valve discharge temperatures about 100 degrees above normal range. (These are incorrectly reported to Zewe to be about 50 degrees lower than they really are.) He attributes the discrepancy to the fact that the PORV had been leaking anyway, and to residual heat from the early discharge of steam from the PORV when it opened (supposedly) for just a few seconds. (2) At 4:14 3461:... checks over the reactor coolant instruments and quickly concludes there is a steam bubble in the "hot legs"—the pipes leading from the reactor to the steam generators—of the reactor coolant loop. With the coolant system pressure so low, there must be a bubble somewhere else, expanding and forcing water into the pressurizer. "I went to the computer," he will later testify, "and punched out the temperatures on both the valves and the electromatic ( 1981:, and the NRC shared responsibility for the shortcomings in operator training. Those inadequacies were compounded by design flaws that undermined the efforts of the plant staff to deal with the accident. They included the cacophony of undifferentiated alarms, the inconvenient arrangement of instruments and controls, and the absence of clear indicators either of levels of water in the pressure vessel or of the position of the stuck-open PORV. 1581: 250: 3689:

Although one stack monitor that was calibrated to measure very low levels of radiation went off-scale early in the accident, readings from other instruments provided reasonably reliable information about releases from the plant. The highest reading was 7 millirems per hour; most measurements were in the range of 1 millirem per hour or less. Those values were far below the amount of radiation normally present in the environment.

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position lights for one block valve were covered by a yellow maintenance tag. The reason why the operator missed the lights for the second valve is not known, although one theory is that his own large belly hid it from his view. The valves may have been left closed during a surveillance test two days earlier. With the block valves closed, the system was unable to pump water. The closure of these valves was a violation of a key

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on – RC-R V2 open." This design is a violation of basic HFE principles as referenced by the following provision of MIL-STD-1472B, paragraph 5.2.2.1.4-. "The absence or extinguishment of a signal or visual indication shall not be used to denote a 'go-ahead,' 'ready,' 'in-tolerance,' or completion condition ...Changes in display status shall signify changes in functional status rather than results of control actuation alone."

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elevated levels were still below those seen in deer in other parts of the country during the height of atmospheric weapons testing. Had there been elevated releases of radioactivity, increased levels of iodine-131 and cesium-137 would have been expected to be detected in cattle and goat's milk samples. Elevated levels were not found. A later study noted that the official emission figures were consistent with available

8829: 1595: 896: 644:(EPA) began daily sampling of the environment at the three stations closest to the plant. Continuous monitoring at 11 stations was established on April 1 and was expanded to 31 stations on April 3. An inter-agency analysis concluded that the accident did not raise radioactivity far enough above background levels to cause even one additional cancer death among the people in the area, but measures of 208:(LOCA). TMI training and operating procedures left operators and management ill-prepared for the deteriorating situation caused by the LOCA. During the accident, those inadequacies were compounded by design flaws, such as poor control design, the use of multiple similar alarms, and a failure of the equipment to indicate either the coolant-inventory level or the position of the stuck-open PORV. 3465:) relief valves." Based on readings showing the relief valve discharge line some 30 degrees hotter than the safety valve discharge lines, Mehler dismisses the pressurizer level reading and moves to a fresh conclusion: The PORV is leaking. Mehler orders the PORV block valve closed... has arrived at exactly the right decision just 20 minutes after coming on the scene fresh from the outside. 329:, initially equivalent to approximately 6% of the pre-trip power level. Because steam was no longer being used by the turbine and feed was not being supplied to the steam generators, heat removal from the reactor's primary water loop was limited to steaming the small amount of water remaining in the secondary side of the steam generators to the condenser using turbine bypass valves. 360:

the pressurizer relief tank, could have hinted at a stuck valve had operators noticed its higher-than-normal reading. It was not, however, part of the "safety grade" suite of indicators designed to be used after an incident, and personnel had not been trained to use it. Its location behind the seven-foot-high instrument panel also meant that it was effectively out of sight.

356:—went out, the operators believed that the valve was closed. In fact, the light when on only indicated that the PORV pilot valve's solenoid was powered, not the actual status of the PORV. While the main relief valve was stuck open, the operators believed the unlighted lamp meant the valve was shut. As a result, they did not correctly diagnose the problem for several hours. 612:

large-scale release of radioactive material. However, it was determined that there was no oxygen present in the pressure vessel, a prerequisite for hydrogen to burn or explode. Immediate steps were taken to reduce the hydrogen bubble, and by the following day it was significantly smaller. Over the next week, steam and hydrogen were removed from the reactor using a

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and conducted inspections. It had no authority to tell the utility what it should do to stabilize the reactor, no capability for operating the plant, and no power to order an evacuation of the surrounding area. Its role was largely limited to collecting information and making recommendations. The NRC lacked a command structure for dealing with a major accident.

537:, to whom Thornburgh assigned responsibility for collecting and reporting on information about the accident. The uncertainty of operators at the plant was reflected in fragmentary, ambiguous, or contradictory statements made by Met Ed to government agencies and to the press, particularly about the possibility and severity of off-site radioactivity releases. 762:. The only differences were that the operators at Davis–Besse identified the valve failure after 20 minutes, where at TMI it took 80 minutes, and the fact that the Davis–Besse facility was operating at 9% power, against TMI's 97%. Although Babcock engineers recognized the problem, the company failed to clearly notify its customers of the valve issue. 1092:, are so called by Perrow because such accidents are inevitable in extremely complex systems. Given the characteristic of the system involved, multiple failures that interact with each other will occur, despite efforts to avoid them. Events which appear trivial initially cascade and multiply unpredictably, creating a much larger catastrophic event. 1207:, with the intent of cleaning up the site for less money than is available in a dedicated fund. On May 8, 2023, TMI-2 solutions announced that 99% of the nuclear fuel has been cleaned up and that the site has entered the next phase of clean-up that will last until 2029. TMI-2 solutions plans to finish clean-up and demolish the plant by 2052. 1048:

safety test results prior to the accident. Under a plea-bargaining agreement, Met Ed pleaded guilty to one count of falsifying records and no contest to six other charges, four of which were dropped, and agreed to pay a $ 45,000 fine and set up a $ 1 million account to help with emergency planning in the area surrounding the plant.

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in training they had been instructed to never allow. This confusion was a key contributor to the initial failure to recognize the accident as a LOCA and led operators to turn off the emergency core cooling pumps, which had automatically started after the PORV stuck and core coolant loss began, due to fears the system was being overfilled.

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who both claimed that no radioactivity had been released. Readings from instruments at the plant and off-site detectors had detected radioactivity releases, albeit at levels that were unlikely to threaten public health as long as they were temporary, and providing that containment of the then highly contaminated reactor was maintained.

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shipped off-site, reactor fuel and most core debris shipped off-site to a Department of Energy facility, and the remainder of the site being monitored. The owner planned to keep the facility in long-term, monitoring storage until the operating license for the TMI-1 plant expired, at which time both plants would be decommissioned.

637:(14 μSv) to the two million people near the plant. In comparison, a patient receives 3.2 mrem (32 μSv) from a chest X-ray—more than twice the average dose of those received near the plant. On average, a U.S. resident receives an annual radiation exposure from natural sources of about 310 mrem (3,100 μSv). 4906:

was no detonation. The hottest gas was the gas that burned at approximately 6 s prior to the end of the burn. Even though the gas was losing heat to the unburned gas and surrounding surfaces after it burned, compression heating was dominant and significantly increased its temperature until the pressure peaked.

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On average, a U.S. resident receives an annual radiation exposure from natural sources of about 310 millirem (3.1 millisieverts or mSv). Radon and thoron gases account for two-thirds of this exposure. Cosmic, terrestrial, and internal radiation account for the rest. Man-made sources of radiation from

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Finally..., a shift supervisor who had just arrived at the plant..., concluded from the pressure and temperature readings in the primary loop that the PORV was at least partially open. He was not certain of what was happening in the core, but he reasoned that no harm and perhaps some benefit could be

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When the feedwater flow stopped, the temperature of the reactor coolant increased. The rapidly heating water expanded. The pressurizer level (the level of the water inside the pressurizer tank) rose and the steam in the top of the tank compressed. Pressure inside the pressurizer built to 2,255 pounds

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portrays Three Mile Island in the 1970s serving as a mutant prison run by the film's main antagonist William Stryker and his team of scientists, where they experimented on and combined the mutants' powers for the Weapon X and Weapon XI programs. The film portrays the 1979 accident being caused by the

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Unit 2 continues to be licensed and regulated by the Nuclear Regulatory Commission in a condition known as Post Defueling Monitored Storage. The TMI-2 reactor has been permanently shut down with the reactor coolant system drained, the radioactive water decontaminated and evaporated, radioactive waste

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A peer-reviewed research article by Dr. Steven Wing found a significant increase in cancers between 1979 and 1985 among people who lived within ten miles of TMI. In 2009, Dr. Wing stated that radiation releases during the accident were probably "thousands of times greater" than the NRC's estimates. A

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Initially, GPU planned to repair the reactor and return it into service. However, TMI-2 was too badly damaged and contaminated to resume operations; the reactor was gradually deactivated and permanently closed. TMI-2 had been online for only three months but now had a ruined reactor vessel and a

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and in the interest of taking every precaution, I am advising those who may be particularly susceptible to the effects of any radiation, that is, pregnant women and pre-school aged children, to leave the area within a five-mile radius of the Three Mile Island facility until further notice. We've also

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and obtained a sample of primary loop water. Seven hours into the emergency, new water was pumped into the primary loop and the backup relief valve was opened to reduce pressure so that the loop could be filled with water. After 16 hours, the primary loop pumps were turned on once again, and the

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The operators had not been trained to understand the ambiguous nature of the PORV indicator and to look for alternative confirmation that the main relief valve was closed. A downstream temperature indicator, the sensor for which was located in the tail pipe between the pilot-operated relief valve and

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a.m., he ordered that a backup for the PORV, called a block valve, be closed. By that time, about thirty-two thousand gallons of coolant, more than one-third of the volume in the primary system, had flowed out of the stuck-open PORV. None of the staff in the control room took action to determine how

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An indicator light in the control room shows when the PORV has been ordered to close—that is, when power to the valve opening solenoid is cut off—but does not show when the valve actually closes. It is now known that the valve did not, if fact, close as it was designed to do. The operators, however,

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Invalid Information. The PORV status indicator is a single red light located on Panel 4. The light is designed to come on when an electrical signal is transmitted to the PORV to open, and go out when a signal is transmitted for the valve to close. As indicated in Figure 3 the light is labeled "Light

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The Reactor Coolant Drain Tank (RCDT) is designed to condense and cool the steam effluent from the pressurizer safety and relief valves if they should ever be actuated. The tank also serves as a collection point for the liquid waste disposal system... Steam discharged from the code safety valves and

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The NRC conducted detailed studies of the accident's radiological consequences, as did the Environmental Protection Agency, the Department of Health, Education and Welfare (now Health and Human Services), the Department of Energy, and the Commonwealth of Pennsylvania. Several independent groups also

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The primary system (also called the Reactor Coolant System) consists of the reactor vessel, the steam generators, the reactor coolant pumps, a pressurizer, and the connecting piping. A reactor coolant loop is a reactor coolant pump, a steam generator, and the piping that connects these components to

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The Kemeny Commission noted that Babcock & Wilcox's PORV had previously failed on 11 occasions, nine of them in the open position, allowing coolant to escape. The initial causal sequence of events at TMI had been duplicated 18 months earlier at another Babcock & Wilcox reactor, the

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were released into the reactor coolant. Since the PORV was stuck open and the loss of coolant accident was still in progress, primary coolant with fission products and/or fuel was released and ultimately ended up in the auxiliary building. The auxiliary building was outside the containment boundary.

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On the third day following the accident, a hydrogen bubble was discovered in the dome of the pressure vessel and became the focus of concern. A hydrogen explosion could breach the pressure vessel and, depending on its magnitude, might compromise the integrity of the containment building leading to a

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Scranton held a press conference in which he was reassuring, yet confused, about this possibility, stating that though there had been a "small release of radiation...no increase in normal radiation levels" had been detected. These were contradicted by another official, and by statements from Met Ed,

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a.m., 165 minutes after the start of the problem, that radiation alarms activated when the contaminated water reached detectors; by that time, the radiation levels in the primary coolant water were around 300 times expected levels, and the general containment building was seriously contaminated with

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This steam bubble was invisible for the operators, and this mechanism had not been trained. Indications of high water levels in the pressurizer contributed to confusion, as operators were concerned about the primary loop "going solid", (i.e., no steam pocket buffer existing in the pressurizer) which

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of the primary coolant. With the coolant contraction and loss of coolant through the open PORV, RCS pressure dropped as did pressurizer level after peaking 15 seconds after the turbine trip. Also, 15 seconds after the turbine trip, coolant pressure had dropped to 2,205 psi (152.0 bar), the

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Given that the steam generators were no longer receiving feedwater, heat transfer from the reactor coolant system (RCS) was greatly reduced, and RCS temperature rose. The rapidly heating coolant expanded and surged into the pressurizer, compressing the steam bubble at the top. When RCS pressure rose

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To prevent nuclear accidents as serious as Three Mile Island, fundamental changes will be necessary in the organization, procedures, and practices—and above all—in the attitudes of the Nuclear Regulatory Commission and, to the extent that the institutions we investigated are typical, of the nuclear

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The hydrogen burn occurred throughout essentially all of the 2,033,000 ft3 (57,600 m3) containment during a period of approximately 12 s. Less than 5% of the burning took place in the first 6 s, less than 40% during the next 3 s, and more than half of the burning occurred during the last 3 s. There

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Another significant question that the cleanup of the containment building raised was why more radioactive iodine had not escaped from the plant. Although the accident discharged up to 13 million curies of radioactive noble gases to the environment, it released very little of the much more hazardous

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By tradition, structure, and statutory mandate, the agency was ill prepared and ill equipped to deal with an emergency at a nuclear plant. It was not an operational agency that ran plants or carried out emergency procedures but a deliberative agency that made rules, considered license applications,

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An indicator light has been installed in the control room, connecting to the opening-and-closing mechanism in the relief valve: when electric power is passed to the solenoid, permitting the valve to open, the light goes on; when diminished pressure in the pressurizer cuts off power to the solenoid,

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coolant to escape. This was not the first time that the PORV had stuck open at TMI-2, and it was a chronic problem at Babcock & Wilcox plants. The same sequence of events had occurred at Davis–Besse in 1977. In that case, an operator recognized that the valve was open and immediately blocked it.

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In September 2024, Constellation Energy announced plans to restart the Three Mile Island nuclear plant to sell the power to Microsoft, demonstrating the immense power needs of the tech sector as they build data centers to support artificial intelligence. Constellation expects the Unit 1 reactor at

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According to health researcher Joseph Mangano, early scientific publications estimated no additional cancer deaths in the 10 mi (16 km) area around TMI, based on these numbers. Disease rates in areas farther than 10 miles from the plant were not examined. Local activism in the 1980s,

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were released. Total releases according to these figures were a relatively small proportion of the estimated 370 EBq (10 GCi) in the reactor. It was later found that about half the core had melted, and the cladding around 90% of the fuel rods had failed, with 5 ft (1.5 m) of the

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Going by the book as it was taught to them, however, the operators continue to read the pressurizer indicator in the old mode: The coolant level is rising; the system is going solid, for heaven's sake. Convinced by this logic that the system, indeed, is overloaded with coolant water, the operators

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A more important factor contributing to the operators' failure to recognize that a LOCA is in progress is the pressurizer water level indicator. Their training on this particular equipment has taught the operators that the only credible check on the amount of coolant in the system is the indicator

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After an incident at TMI-2 a year earlier during which the PORV stuck open, an indicator light was installed in the control room. That light showed only that a signal had been sent to close the valve—it did not show whether the valve was actually closed—and this contributed to the confusion during

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The purpose of the pressurizer is to control the pressure in the primary loop at a nominal coolant pressure of 2250 lb./in (≈ 153 bars). The primary pressure is regulated by modulating heater power and spray flow from a cold leg… The water in the pressurizer is the only free surface in the primary

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A PWR pressurizer is a vessel with liquid water in the bottom section and saturated steam in the top section. A pressurizer is used to regulate the primary coolant pressure (≈ 150 bars) in PWRs and CANDU reactors. The pressurizer is connected to one of the hot leg pipings with a long surge line...

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In 2009, the NRC granted a license extension which allowed the TMI-1 reactor to operate until April 19, 2034. In 2017, it was announced that operations would cease by 2019 due to financial pressure from inexpensive natural gas, unless lawmakers stepped in to keep it open. When it became clear that

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Program, so that they might find some benefit for their own work. I am always chagrined at the tendency of people to expect that I have a simple, easy gimmick that makes my program function. Any successful program functions as an integrated whole of many factors. Trying to select one aspect as the

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low-level radiation health model to predict 333 excess cancer or leukemia deaths from the 1979 Three Mile Island accident. The ongoing TMI epidemiological research has been accompanied by a discussion of problems in dose estimates due to a lack of accurate data, as well as illness classifications.

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link between these incidences and the accident. The Talbott lab at the University of Pittsburgh reported finding a few, small increased cancer risks within the TMI population. A more recent study reached "findings consistent with observations from other radiation-exposed populations," raising "the

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According to the IAEA, the Three Mile Island accident was a significant turning point in the global development of nuclear power. From 1963 to 1979, the number of reactors under construction globally increased every year except in 1971 and 1978. However, following the event, the number of reactors

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Governor Thornburgh, on the advice of NRC chairman Joseph Hendrie, advised the evacuation "of pregnant women and pre-school age children...within a five-mile radius of the Three Mile Island facility". The evacuation zone was extended to a 20-mile radius on March 30. Within days, 140,000 people had

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On Wednesday, March 28, hours after the accident began, Lieutenant Governor Scranton appeared at a news briefing to say that Met Ed had assured the state that "everything is under control". Later that day, Scranton changed his statement, saying that the situation was "more complex than the company

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connection linking the accident with cancer is difficult to prove. Cleanup at TMI-2 started in August 1979 and officially ended in December 1993, with a total cost of about $ 1 billion (equivalent to $ 2 billion in 2023). TMI-1 was restarted in 1985, then retired in 2019 due to operating

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The commission offered a harsh indictment of Babcock & Wilcox, Met Ed, GPU, and the NRC. It explained that it had no mandate to draw conclusions about the future of the nuclear industry or to make comparisons of nuclear power with other sources of energy. It did not intend to show either that

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Prior to the burn (deflagration), the hydrogen was well mixed with the containment air. The average hydrogen concentration was calculated to be 7.9%, wet basis. The hydrogen burn occurred at all three levels in the containment. The burn was initiated somewhere in the lowest level; probably on the

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The Three Mile Island crisis was quickly followed by several extensive investigations. The NRC, the state of Pennsylvania, congressional committees, and nuclear industry groups sponsored important studies, but the most prominent of the inquiries were conducted by the President's Commission on the

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a.m., with the accident sequence barely settling in, there are other conspicuous clues that the relief valve is still open. Continued discharge of coolant into the reactor coolant drain tank from the stuck-open relief valve causes the tank's pressure to increase. (3) When the pressure reaches 192

2138:

Thyroid cancer incidence has not increased in Dauphin County, the county in which TMI is located. York County demonstrated a trend toward increasing thyroid cancer incidence beginning in 1995, approximately 15 years after the TMI accident. Lancaster County showed a significant increase in thyroid

1164:

GPU formed General Public Utilities Nuclear Corporation as a subsidiary to own and operate the company's nuclear facilities, including Three Mile Island. In 1996, General Public Utilities shortened its name to GPU Inc. In 1998, GPU sold TMI-1 to AmerGen Energy Corporation, a joint venture between

1047:

In 1981, citizens' groups succeeded in a class action suit against TMI, winning $ 25 million in an out-of-court settlement. Part of this money was used to found the TMI Public Health Fund. In 1983, a federal grand jury indicted Metropolitan Edison on criminal charges for the falsification of

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plate-out, not the accident). Also, the tongues of white-tailed deer harvested over 50 mi (80 km) from the reactor subsequent to the accident were found to have significantly higher levels of cesium-137 than in deer in the counties immediately surrounding the power plant. Even then, the

409:

as a steam bubble/water mixture, rather than water, passed through them. The pumps were shut down, and it was believed that natural circulation would continue the water movement. Steam in the system prevented flow through the core, and as the water stopped circulating it was converted to steam in

384:

to fill and sound an alarm at 4:11 a.m. This alarm, along with higher than normal temperatures on the PORV discharge line and unusually high containment building temperatures and pressures, were clear indications that there was an ongoing LOCA, but these indications were initially ignored by

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The Kemeny Commission operated under stringent time constraints. The president instructed it to submit a final report on Three Mile Island within six months after its first meeting. The commission conducted its investigation by assigning staff members and consultants to task forces that examined

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contributed key concepts to a set of intellectual developments in the 1980s that revolutionized the conception of safety and risk. It made the case for examining technological failures as the product of highly interacting systems, and highlighted organizational and management factors as the main

922:

In 1988, the NRC announced that, although it was possible to further decontaminate the Unit 2 site, the remaining radioactivity had been sufficiently contained as to pose no threat to public health and safety. The first major phase of the cleanup was completed in 1990, when workers finished

636:

was reported in the environment. No significant level of radiation was attributed to the TMI-2 accident outside of the TMI-2 facility. According to the Rogovin report, the vast majority of the radioisotopes released were noble gases xenon and krypton resulting in an average dose of 1.4 mrem

564:

In a 2009 article, Gilinsky wrote that it took five weeks to learn that "the reactor operators had measured fuel temperatures near the melting point". He further wrote: "We didn't learn for years—until the reactor vessel was physically opened—that by the time the plant operator called the NRC at

544:

Angry that Met Ed had not informed them before conducting a steam venting from the plant, and convinced that the company was downplaying the severity of the accident, state officials turned to the NRC. After receiving word of the accident from Met Ed, the NRC had activated its emergency response

275:

Blockages are common with these resin filters and are usually fixed easily, but in this case, the usual method of forcing the stuck resin out with compressed air did not succeed. The operators decided to blow compressed air into the water and let the force of the water clear the resin. When they

2972:

At TMI-2, the PORV opened three seconds after the condensate pumps tripped, exactly as designed. Unfortunately, ten seconds later, after the temperature and pressure in the primary system had diminished, it failed to close as designed. The open relief valve allowed growing quantities of reactor

1083:

Perrow concluded that the failure at Three Mile Island was a consequence of the system's immense complexity. Such modern high-risk systems, he realized, were prone to failures however well they were managed. It was inevitable that they would eventually suffer what he termed a 'normal accident'.

918:

Efforts focused on the cleanup and decontamination of the site, especially the defueling of the damaged reactor. Starting in 1985, almost 100 short tons (91 t) of radioactive fuel were removed from the site. Planning and work was partially hampered by too-optimistic views about the damage.

556:

Gilinsky briefed reporters and members of Congress on the situation and informed White House staff, and at 10:00 a.m. met with two other commissioners. However, the NRC faced the same problems in obtaining accurate information as the state and was further hampered by being organizationally

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At 6:56 A.M., one of the plant supervisors—accounts vary on which one—declared a site emergency. The emergency plan for TMI-2 directed that this action be taken if radiation alarms sounded in more than one area. A site emergency meant that there was a possibility of an "uncontrolled release of

332:

When the feedwater pumps tripped, three emergency feedwater pumps started automatically. An operator noted that the pumps were running but did not notice that a block valve was closed in each of the two emergency feedwater lines, blocking emergency feed flow to both steam generators. The valve

4140:

The effects on the population in the vicinity of Three Mile Island from radioactive releases measured during the accident, if any, will certainly be nonmeasurable and nondetectable. During the course of the accident, approximately 2.5 million curies of radioactive noble gases and 15 curies of

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The levels measured outside TMI-2 on March 28 were, by any standard, very small and unlikely to threaten public health—as long as they did not occur continuously over an extended period. Met Ed had twenty instruments for measuring environmental radioactivity in locations surrounding the site.

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became more strident, construction times were significantly lengthened and costs skyrocketed. Until 2012, no U.S. nuclear power plant had been authorized to begin construction since the year before, 1978. Globally, the end of the increase in nuclear power plant construction came with the more

1160:

After the incident at TMI-2, the NRC suspended the license to operate TMI-1, which was owned and operated by Met Ed, one of General Public Utilities Corporation's regional utility operating companies. In 1982, the citizens of the three counties surrounding the site voted overwhelmingly in a

608:" and was highly radioactive, with readings as high as 1,000 rem/h. The two spent five minutes in the building, then withdrew. Houser had gone past the NRC's quarterly dose limit for radiation exposure (3 rem/qtr in 1979) by one and was only admitted back to work the following quarter. 584:

concentration sample in order to ensure there was enough of it in the primary system to shut down the reactor entirely. Unit 2's chemistry supervisor, Edward "Ed" Houser, volunteered to draw the sample after his co-workers were hesitant. Shift supervisor Richard Dubiel asked Pete Velez, the

2752:

The closing of the secondary system caused heat and pressure to rise rapidly in the primary system, largely because the steam generators could no longer remove heat from the water that had come from the core. As a result, eight seconds after the polisher pumps tripped, the reactor scrammed

7140: 430:, and additional heat. This reaction melted the nuclear fuel rod cladding and damaged the fuel pellets, which released radioactive isotopes to the reactor coolant and produced hydrogen gas that is believed to have caused a small explosion in the containment building later that afternoon. 481:

At 6:00 a.m. there was a shift change in the control room. A new arrival noticed that the temperatures in the PORV tail pipe and the holding tanks were excessive, and used a backup—called a block valve—to shut off the coolant venting via the PORV, but around 32,000 US gal

3789:, Gilinsky regarded it as cause for concern but not alarm. He tried to keep his previously scheduled appointments to avoid the appearance of a crisis and, in his capacity as acting chairman, he spent much of the day responding to telephone queries from members of Congress and reporters. 2714:

The function of the turbine bypass system is to remove excess energy from the reactor coolant system by discharging a stated percentage of rated main steam flow directly to the main condensers, i.e. by bypassing the turbine. This heat is rejected to the condenser through the steam dump

867:

under construction in the U.S. declined from 1980 to 1998, with increasing construction costs and delayed completion dates for some reactors. Many similar Babcock & Wilcox reactors on order were canceled. In total, 51 U.S. nuclear reactors were canceled between 1980 and 1984.

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NRC will continue to provide licensing oversight and inspections of the plant until the plant is completely decommissioned, including inspections of the Independent Spent Fuel Storage Installation (ISFSI) until the spent fuel is permanently removed from the site and the license is

937:

In the aftermath of the accident, investigations focused on the amount of radioactivity released. In total, approximately 2.5 megacuries (93 PBq) of radioactive gases and approximately 15 curies (560 GBq) of iodine-131 were released into the environment. According to the

4765:

Arnie Gundersen—a nuclear engineer and former nuclear industry executive turned whistle-blower—has done his own analysis, which he shared for the first time at a symposium in Harrisburg last week. "I think the numbers on the NRC's website are off by a factor of 100 to 1,000," he

878:, 40 planned nuclear power plants already had been canceled before the accident. At the time of the incident, 129 nuclear power plants had been approved, but of those, only 53 which were not already operating were completed. During the lengthy review process, complicated by the 845:

Post-TMI surveys have shown that less than 50% of the American public were satisfied with the way the accident was handled by Pennsylvania state officials and the NRC, and people surveyed were even less pleased with the utility (General Public Utilities) and the plant designer.

3389:

psi, the rupture disc at the top of the tank bursts. Zewe takes note of this around 4:20... With the rupture disc open, coolant from the stuck-open valve running into the reactor coolant drain tank overflows the tank onto the reactor containment building floor. (4) At 4:38

738:

reported that "At about 2:00 pm, with pressure almost down to the point where the huge cooling pumps could be brought into play, a small hydrogen explosion jolted the reactor." Work performed for the Department of Energy in the 1980s determined that the hydrogen burn

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According to Eric Epstein, chair of Three Mile Island Alert, the TMI plant operator and its insurers paid at least $ 82 million in publicly documented compensation to residents for "loss of business revenue, evacuation expenses and health claims." However, a

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long the PORV had been open or to replace the coolant that had escaped. Closing the block valve was a sound decision but insufficient in itself to prevent the severe damage to the core that leaving the PORV open for about two hours and twenty minutes had caused.

2934:

Apparently the valves were closed for routine maintenance, in violation of one of the most stringent rules that the Nuclear Regulatory Commission has. The rule states simply that auxiliary feed pumps can never all be down for maintenance while the reactor is

1896:

The steam generator tubes, steam turbine, condenser, and associated pipes, pumps, and heaters used to convert the heat energy of the reactor coolant system into mechanical energy for electrical generation. Most commonly used in reference to pressurized water

978:, an organization with little credibility among epidemiologists, cited calculations by Mangano that showed a spike in infant mortality in downwind communities two years after the accident. Anecdotal evidence also records effects on the region's wildlife. 1079:'s normal accident theory, which attempts to describe "unanticipated interactions of multiple failures in a complex system". TMI was an example of this type of accident because it was "unexpected, incomprehensible, uncontrollable and unavoidable." 724:

Anti-nuclear political groups disputed the Kemeny Commission's findings, claiming that other independent measurements provided evidence of radiation levels up to seven times higher than normal in locations hundreds of miles downwind from TMI.

272:, the sophisticated filters cleaning the secondary loop water. These filters are designed to stop minerals and other impurities in the water from accumulating in the steam generators and to decrease corrosion rates on the secondary side. 659:

sensitive enough to detect Chinese atmospheric atomic weapons-testing—collected soil samples from the area for the ensuing two weeks and detected no elevated levels of radioactivity, except after rainfalls (likely from natural

818:

first led us to believe". There were conflicting statements about radioactivity releases. Schools were closed, and residents were urged to stay indoors. Farmers were told to keep their animals under cover and on stored feed.

2359:

Findings were consistent with observations from other radiation-exposed populations. These data raise the possibility that radiation released from may have altered the molecular profile of in the population surrounding

842:

left the area. More than half of the 663,500 population within the 20-mile radius remained in that area. According to a survey conducted in April 1979, 98% of the evacuees had returned to their homes within three weeks.

1484:. At one point in the film, an official tells Wells that an explosion at the plant "could render an area the size of the state of Pennsylvania permanently uninhabitable". After the release of the film, Fonda began 958:

based on anecdotal reports of negative health effects, led to scientific studies being commissioned. A variety of epidemiology studies have concluded that the accident had no observable long-term health effects.

352:. There was no direct indication of the valve's actual position. A light on a control panel, installed after the PORV had stuck open during startup testing, came on when the PORV opened. When that light—labeled 971:

possibility that radiation released from may have altered the molecular profile of in the population surrounding TMI", establishing a potential causal mechanism, although not definitively proving causation.

1930:

the reactor vessel. The primary function of the reactor coolant system is to transfer the heat from the fuel to the steam generators. A second function is to contain any fission products that escape the fuel.

1765: 9426: 1543:; Lake Barrett, an independent energy consultant who served as the NRC's on-site director for the TMI-2 cleanup; Eric Epstein, chairman of TMI Alert, a nuclear watchdog organization in central Pennsylvania; 4744: 368:

Less than a minute after the beginning of the event, the water level in the pressurizer began to rise, even though RCS pressure was falling. With the PORV stuck open, coolant was being lost from the RCS, a

1539:

on May 4, 2022. The documentary recounts the events, controversies, and lingering effects of the accident. Featured in the series are Rick Parks, a TMI nuclear engineer turned whistleblower against

5444:

For some time after the accident, before the actual damage conditions were well understood, GPU envisioned the unit to return to service. Extensive planning efforts were directed towards this end.

1184:

to form Exelon. In 2003, Exelon bought the remaining shares of AmerGen from British Energy. In 2009, Exelon Nuclear absorbed and dissolved AmerGen. Along with TMI Unit 1, Exelon Nuclear operates

1196:

the subsidy legislation would not pass, Exelon decided to retire the plant. TMI Unit 1 shut down on September 20, 2019. Following the permanent shutdown, Unit 1 is in decommissioning, moving to

257:

In the night hours before the incident, the TMI-2 reactor was running at 97% power while the companion TMI-1 reactor was shut down for refueling. The main chain of events leading to the partial

9297: 8376: 340:

After the reactor tripped, secondary system steam valves operated to reduce steam generator temperature and pressure, cooling the RCS and lowering RCS temperature, as designed, resulting in a

211:

The accident heightened anti-nuclear safety concerns among the general public and led to new regulations for the nuclear industry. It accelerated the decline of efforts to build new reactors.

1211:

Three Mile Island to come back online in 2028, subject to approval by the Nuclear Regulatory Commission. Constellation also plans to apply to extend the plant’s operations to at least 2054.

3583:

Thornburgh assigned responsibility for collecting and reporting information about the accident to Scranton because of his confidence in the ability and integrity of the lieutenant governor.

5705:

Goldenberg, David; Russo, Mariano; Houser, Kenneth; Crist, Henry; Derr, Jonathan B.; Walter, Vonn; Warrick, Joshua I.; Sheldon, Kathryn E.; Broach, James; Bann, Darrin V. (July 17, 2017).

9421: 1320: 200:(PORV) in the primary system, which allowed large amounts of water to escape from the pressurized isolated coolant loop. The mechanical failures were compounded by the initial failure of 1126:) had suffered no reactor accidents, defined as the uncontrolled release of fission products to the environment resulting from damage to a reactor core. In his testimony, Rickover said: 572:

It was still not clear to the control room staff that the primary loop water levels were low and that over half of the core was exposed. A group of workers took manual readings from the

32: 743:), which went essentially unnoticed for the first few days, occurred 9 hours and 50 minutes after initiation of the accident, had a duration of 12 to 15 seconds and did not involve a 3397:

a.m., the temperature inside the containment building is up from 120°F to 170°F, and building pressure has increased from 0 to 2.5 psi—still another sign that the PORV is stuck open.

721:. The reactor vessel—the second level of containment after the cladding—maintained integrity and contained the damaged fuel with nearly all of the radioactive isotopes in the core. 696:

According to the official figures, as compiled by the 1979 Kemeny Commission from Met Ed and NRC data, a maximum of 480 PBq (13 MCi) of radioactive noble gases, primarily

4936:

west side. Even though the burn time was about 15 sec, nearly all of the burning occurred during a 6-sec period. Over one-half of the burning occurred during the last 3-sec period.

2808: 1013:—told his cabinet after visiting the plant that the accident was minor but reportedly declined to do so in public, in order to avoid offending Democrats who opposed nuclear power. 1009:

The accident enhanced the perceived credibility of anti-nuclear groups and triggered protests around the world. President Carter—who had specialized in nuclear power while in the

337:(NRC) rule, according to which the reactor must be shut down if all auxiliary feed pumps are closed for maintenance. This was later singled out by NRC officials as a key failure. 9113: 2158:

Levin, R. J.; De Simone, N. F.; Slotkin, J. F.; Henson, B. L. (August 2013). "Incidence of thyroid cancer surrounding Three Mile Island nuclear facility: the 30-year follow-up".

693:. It was instructed to produce a final report within six months, and after public hearings, depositions, and document collection, released a completed study on October 31, 1979. 1723:

Three Mile Island: a report to the commissioners and to the public. The problem was caused by a cooling problem and caused some of the core to melt in the 2nd reactor. Volume I

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a.m. an auxiliary building operator reports that the automatic containment sump (floor drain) pumps are pumping this water into the next-door auxiliary building... (5) By 5:00

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This was evidenced by the radiation alarms that eventually sounded. However, since very little of the fission products released were solids at room temperature, very little

1504:), personally lobbied in favor of nuclear power. Teller suffered a heart attack shortly after the incident and joked that he was the only person whose health was affected. 911:

containment building that was unsafe to walk in. Cleanup started in August 1979 and officially ended in December 1993, with a total cleanup cost of about $ 1 billion.

345:

reset setpoint for the PORV. Electric power to the PORV's solenoid was automatically cut, but the relief valve was stuck open with coolant water continuing to be released.

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across the country in the following months. The largest demonstration was held in New York City in September 1979 and involved 200,000 people, with speeches given by

996: 732:

The Kemeny Commission referred to "a burn or an explosion that caused pressure to increase by 28 pounds per square inch (190 kPa) in the containment building", while

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On the day following the accident, March 29, control room operators needed to ensure the integrity of the reactor vessel. In order to do this, someone needed to draw a

1148:

After the accident, Three Mile Island used only one nuclear generating station, TMI-1, which is on the right. TMI-2, to the left, has not been used since the accident.

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automatically. The control rods entered the core and terminated the production of heat from nuclear fission. But the problem of dealing with decay heat remained...

301:(PORV) opened, relieving steam through piping to the reactor coolant drain tank in the containment building basement. RCS pressure continued to rise, reaching the 7004: 1355:

GPU submitted a request for a proposal to amend the TMI-2 license to a "possession-only" license and to allow the facility to enter long-term monitoring storage.

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in April 1979. The commission consisted of a panel of 12 people, specifically chosen for their lack of strong pro- or anti-nuclear views, and headed by chairman

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retrospective study of the Pennsylvania Cancer Registry found an increased incidence of thyroid cancer in some counties south of TMI (although, notably, not in

405:

a.m., after almost 80 minutes with a growing steam bubble in the reactor pressure vessel head, the primary loop's four main reactor coolant pumps began to

9825: 8362: 8098: 9231: 9157: 8432: 5753: 9493: 8693: 8393: 8385: 2204:

Han, Y. Y.; Youk, A. O.; Sasser, H.; Talbott, E. O. (November 2011). "Cancer incidence among residents of the Three Mile Island accident area: 1982–1995".

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The accident did not initiate the demise of the U.S. nuclear power industry, but it did halt its historic growth. Additionally, as a result of the earlier

6090: 915:, in his 2007 preliminary assessment of major energy accidents, estimated that the TMI accident caused a total of $ 2.4 billion in property damages. 9086: 8437: 6737: 6590: 4620: 4779: 9845: 9488: 9302: 9180: 7436: 6072: 6052: 1017: 163: 97: 9880: 9031: 8477: 8207: 6763: 3024: 414:

a.m., the top of the reactor core was exposed, and the intense heat caused a reaction to occur between the steam forming in the reactor core and the

6026: 10170: 9476: 8994: 7480: 6853: 6402: 1161:

non-binding resolution to retire Unit 1 permanently. In 1985, a 4–1 vote by the Nuclear Regulatory Commission allowed TMI-1 to resume operations.

942:, using the official radioactivity emission figures, "The average radiation dose to people living within 10 miles of the plant was eight 512: 508: 385:

operators. At 4:15 a.m., the relief diaphragm of the pressurizer relief tank ruptured, and radioactive coolant began to leak into the general

5999: 4244: 10185: 9446: 8999: 7331: 7320: 1084:

Therefore, he suggested, we might do better to contemplate a radical redesign, or if that was not possible, to abandon such technology entirely.

8967: 8962: 8957: 8338: 2518:

The chain of events that set off the severe accident at TMI-2 and melted a substantial portion of its core began innocently enough at 4:00 A.M.

1620: 1303:

An Advisory Panel for the Decontamination of TMI-2, composed of citizens, scientists, and state and local officials, held its first meeting in

6954: 4028: 3911: 380:

With the PORV still open, the pressurizer relief tank that collected the discharge from the PORV overfilled, causing the containment building

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A persistent optimism existed that the damage beyond the known areas was not as bad as some estimates would have it. In fact, it was worse.

904: 389:. This radioactive coolant was pumped from the containment building sump to an auxiliary building, outside the main containment, until the 155: 7427: 9505: 9197: 9066: 8554: 8499: 8252: 7649: 7473: 1551: 1156:

TMI-2 in February 2014. The cooling towers are on the left. The spent fuel pool with containment building of the reactor is on the right.

1100:

causes of failures. Technological disasters could no longer be ascribed to isolated equipment malfunction, operator error or acts of God.

8842: 8516: 8328: 7549: 6253:"Statement of Admiral F. L. "Skip" Bowman, U.S. Navy, Director, Naval Nuclear Propulsion Program before the House Committee on Science" 1625: 883: 700:, were released by the event. These noble gases were considered relatively harmless, and only 481–629 GBq (13.0–17.0 Ci) of 10135: 9466: 9436: 9359: 9006: 8722: 8699: 8619: 7724: 7634: 932: 261:

on Wednesday, March 28, 1979, began at 4:00:36 a.m. EST in TMI-2's secondary loop, one of the three main water/steam loops in a

8631: 6568: 1815: 9665: 9633: 9324: 9202: 9190: 9021: 8560: 8292: 7524: 2547:

The system used to remove energy from the reactor core and transfer that energy either directly or indirectly to the steam turbine.

798: 520: 268:

The initial cause of the accident happened 11 hours earlier, during an attempt by operators to fix a blockage in one of the eight

9900: 9704: 9660: 9640: 9628: 9608: 9409: 8952: 8942: 8933: 8894: 8759: 8452: 8407: 8310: 8013: 7963: 7719: 7659: 7554: 7417: 276:

forced the resin out, a small amount of water forced its way past a stuck-open check valve and found its way into an instrument

9414: 9106: 8873: 8457: 8447: 8033: 7923: 7819: 7754: 7342: 6377: 5344: 4819: 6497: 4322: 9930: 9716: 9207: 9164: 9152: 8354: 8305: 8038: 8018: 7814: 7809: 7709: 7624: 7534: 7252: 7229: 7210: 7149: 7128: 7088: 7069: 6825: 6036: 5982: 5952: 5024: 3034: 766: 759: 2375: 10165: 9382: 8754: 8549: 8333: 8167: 7968: 7845: 7824: 7734: 7689: 7594: 7564: 7163: 6887: 3738: 954:, and 100 millirem is about a third of the average background level of radiation received by US residents in a year." 950:), and no more than 100 millirem (1 mSv) to any single individual. Eight millirem is about equal to a chest 6609: 4214: 2674:. U.S. Nuclear Regulatory Commission, Human Resources Training and Development (HRTD). October 2009. pp. 2.2-7, 2.2-8 677:

Several state and federal government agencies mounted investigations into the crisis, the most prominent of which was the

10130: 9895: 9743: 9655: 9623: 9592: 9587: 9252: 9219: 8984: 8343: 7933: 7779: 7729: 7514: 7260: 6111: 1630: 975: 531: 5658:"A reevaluation of cancer incidence near the Three Mile Island nuclear plant: the collision of evidence and assumptions" 4183: 4153: 1993: 1468:

premiered and was initially met with backlash from the nuclear power industry, claiming it to be "sheer fiction" and a "

10175: 10145: 9809: 9377: 9369: 9292: 9287: 8732: 8727: 8582: 8487: 8422: 8078: 7918: 7749: 7614: 7609: 7569: 7519: 7496: 7172: 6667: 5120: 4997: 4919: 4889: 2996: 2892: 2855: 2780: 1727: 1655: 1371:

GPU submitted its funding plan for placing $ 229 million in escrow for radiological decommissioning of the plant.

348:

In post-accident investigations, the indication for the PORV was one of many design flaws identified in the operators'

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Perrow, C. (1982). "The President's Commission and the Normal Accident". In Sils, D.; Wolf, C.; Shelanski, V. (eds.).

4710: 9572: 8748: 8717: 8577: 8506: 8192: 8172: 8083: 8048: 8043: 7789: 6982: 6931: 5456:

Sovacool, Benjamin K. (2008). "The costs of failure: A preliminary assessment of major energy accidents, 1907–2007".

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Levin, R. J. (2008). "Incidence of thyroid cancer in residents surrounding the Three-Mile Island nuclear facility".

2632:(1 ed.). London, UK; San Diego, California; Cambridge, Massachusetts; Oxford, UK: Academic Press. p. 141. 2325:

Goldenberg, D, Russo, M, Houser, K, Crist, H, Derr JB, Walter V, Warrick JI, Sheldon KE, Broach J, Bann, DV (2017).

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Levin, R. J. (2008). "Incidence of thyroid cancer in residents surrounding the Three-Mile Island nuclear facility".

10155: 9956: 9334: 9319: 9185: 8609: 8182: 8112: 8028: 8003: 7983: 7739: 7694: 7664: 7390: 4820:"Report of The President's Commission On The Accident at Three Mile Island: The Need For Change: The Legacy Of TMI" 2576:

A tank or vessel that acts as a head tank (or surge volume) to control the pressure in a pressurized water reactor.

1614: 1037: 810: 220: 7405: 7355:

a review of subsequent casualties by Harvey Wasserman and Norman Solomon with Robert Alveraez and Eleanore Walters

7305: 1016:

Members of the American public, concerned about the release of radioactive gas from the accident, staged numerous

561:

and did not have the authority either to tell the utility what to do or to order an evacuation of the local area.

284:, condensate booster pumps, and condensate pumps to turn off around 4:00 a.m., which would, in turn, cause a 10195: 9961: 9721: 9694: 9681: 9560: 9555: 9550: 9545: 9127: 8511: 8242: 8217: 8212: 7998: 7948: 7860: 7529: 7119:

Report of The President's Commission on the Accident at Three Mile Island: The Need for Change: The Legacy of TMI

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Human Factors Evaluation of Control Room Design and Operator Performance at Three Mile Island – 2 (NUREG/CR-1270)

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core temperature began to fall. A large part of the core had melted, and the system was dangerously radioactive.

2530: 882:

seven years later, Federal requirements to correct safety issues and design deficiencies became more stringent,

9786: 9525: 9312: 9247: 9016: 8897: 8809: 8247: 8237: 8152: 8147: 7943: 7604: 7363: 7244: 7202: 6097: 5707:"Altered molecular profile in thyroid cancers from patients affected by the Three Mile Island nuclear accident" 2327:"Altered molecular profile in thyroid cancers from patients affected by the Three Mile Island nuclear accident" 1955: 1608: 1064: 656: 8647: 4862: 2915: 10150: 9860: 9535: 9456: 9049: 8442: 8257: 8142: 8132: 8023: 8008: 7973: 7829: 7644: 7544: 7186: 4848: 4790: 4351: 4273: 4094: 4070: 3977: 3953: 2434: 1792: 1166: 824: 805: 334: 6472: 1871:

Level 5: Accident with Wider Consequences; Three Mile Island, USA, 1979 – Severe damage to the reactor core.

9770: 9753: 9530: 9354: 9277: 9137: 9056: 9011: 8947: 8905: 8603: 8417: 8227: 8162: 8117: 8053: 7850: 7704: 6711: 1060: 963: 5913: 5772: 1883: 9392: 8537: 7928: 7784: 7539: 5380: 1909: 1670: 862:. The Three Mile Island accident is one of the factors cited for the decline of new reactor construction. 298: 197: 7273: 6542: 6283: 5271: 553:

and commissioner Victor Gilinsky initially viewed the accident as a "cause for concern but not alarm".

10180: 9916: 9875: 9451: 9267: 8928: 8866: 8543: 8282: 8222: 8187: 8122: 8088: 8068: 7988: 7938: 7911: 7896: 7891: 7876: 7855: 7804: 7714: 7589: 6416: 5802:"Cancer risks near nuclear facilities: the importance of research design and explicit study hypotheses" 4949: 4551: 4510: 4472: 3330: 1949: 1177:

Corporation and dissolved, and the maintenance and administration of Unit 2 was contracted to AmerGen.

633: 596:

Wearing excessive amounts of protective clothing—three pairs of gloves, one pair of rubber boots and a

7430:, a PowerPoint presentation on the TMI-2 cleanup by Lake Barrett, who directed the project for the NRC 7328: 7317: 5974:

Social Protest and Policy Change: Ecology, Antinuclear, and Peace Movements in Comparative Perspective

3802: 3761: 3702: 3664: 3630: 3596: 3559: 3521: 3478: 3292: 2494: 2457: 1152: 10024: 9974: 9711: 9329: 8833: 8769: 8678: 8412: 8300: 8202: 8157: 8073: 8058: 7799: 7744: 7654: 7559: 6738:"Constellation Energy to restart Three Mile Island nuclear plant, sell the power to Microsoft for AI" 6116: 3057:

Malone, T. B.; Kirkpatrick, M.; Mallory, K.; Eike, D.; Johnson, J. H.; Walker, R. W. (January 1980).

2559: 2245: 2243: 1600: 900: 648:

were not included because the EPA found no contamination in water, soil, sediment, or plant samples.

589:

foreman for Unit 2, to join Houser. Velez would monitor airborne radiation levels and ensure that no

306: 302: 262: 224: 5634: 5217: 4989:

Report of the Commission on The Accident at Three Mile Island—The Need For Change: The Legacy of TMI

4895:(Report). U.S. Department of Energy, Hanford Office. p. 2-1. DOE Contract No. DE-AC06-77RL01030 4745:"Investigation: Revelations about Three Mile Island disaster raise doubts over nuclear plant safety" 2988:

Report of the Commission on The Accident at Three Mile Island—The Need For Change: The Legacy of TMI

2884:

Report of the Commission on The Accident at Three Mile Island—The Need For Change: The Legacy of TMI

2847:

Report of the Commission on The Accident at Three Mile Island—The Need For Change: The Legacy of TMI

2768:

Report of the Commission on The Accident at Three Mile Island—The Need For Change: The Legacy of TMI

1173:. (GPU was legally obliged to continue to maintain and monitor TMI-2.) In 2001, GPU was acquired by 669:

data, though others have noted the incompleteness of this data, particularly for releases early on.

10012: 9481: 9307: 9257: 8197: 8177: 8137: 4625: 2252:"Cancer rates after the Three Mile Island nuclear accident and proximity of residence to the plant" 1509: 939: 777: 718: 600:—the two navigated the reactor auxiliary building to draw the sample. However, Houser had lost his 524: 370: 309:

of 2,355 psi (162.4 bar) eight seconds after the turbine trip. The reactor automatically

205: 167: 7411: 5078: 2240: 227:

increase in the rate of cancer, while other studies did not. Due to the nature of such studies, a

9733: 8794: 8784: 8262: 7669: 7619: 7599: 7358: 7281:, a website about the accident, with many reports and other relevant documents created by nearby 6260: 5918: 5458: 4630: 1469: 625: 5301:

Hultman, N.; Koomey, J. (2013). "Three Mile Island: The driver of US nuclear power's decline?".

4925:(Report). Vol. 4. U.S. Department of Energy, Hanford Office. p. iii. DE-AV07-76IDO1570 9936: 9801: 8789: 8590: 8232: 7993: 7794: 7639: 7629: 2627: 2589: 1501: 1497: 1144: 322: 196:

The accident began with failures in the non-nuclear secondary system, followed by a stuck-open

27: 8384: 7306:

Annotated bibliography for Three Mile Island from the Alsos Digital Library for Nuclear Issues

7005:"Lake Barrett's Reality-Grounded Perspective on Netflix's Drama 'Meltdown: Three Mile Island'" 6815: 5754:"In Baby Teeth, a Test of Fallout; A Long-Shot Search for Nuclear Peril in Molars and Cuspids" 2153: 2151: 1403:

The processing of accident-generated water was completed involving 2.23 million gallons.

1387:

NRC published a notice of opportunity for a hearing on GPU's request for a license amendment.

10108: 10048: 10030: 9778: 9282: 9226: 9214: 9142: 9071: 8859: 7699: 7302:

citizens radiation monitoring group for the Three Mile Island and Peach Bottom nuclear plants

6473:"Three Mile Island finds buyer as times change Deal excludes reactor in '79 nuclear accident" 5375: 5079:"Examination of relocated fuel debris adjacent to the lower head of the TMI-2 reactor vessel" 3170: 3163: 2948: 2728: 1547:, an American theoretical physicist; and residents of the communities affected by the event. 1185: 1033: 1005:

Anti-nuclear protest following the Three Mile Island accident, Harrisburg, Pennsylvania, 1979

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conducted its own investigation, which focused on the need to improve evacuation procedures.

527: 433: 212: 7117: 4367:"Comments on "A Re-Evaluation of Cancer Incidence Near the Three Mile Island Nuclear Plant"" 4323:"Population Dose and Health Impact of the Accident at the Three Mile Island Nuclear Station" 2594:(1 ed.). London / San Diego, CA / Cambridge, MA / Oxford: Academic Press. p. 116. 2029: 1829:(1). Vienna, Austria: Division of Public Information, International Atomic Energy Agency: 46 10036: 9870: 9699: 9076: 8916: 8779: 8641: 8127: 7774: 6790:"Three Mile Island accident was eerily foreshadowed by a Hollywood blockbuster days before" 6298: 6180: 5860: 5467: 5310: 5242: 5183: 4287:

Field, R. W. (June 1993). "137Cs levels in deer following the Three Mile Island accident".

2213: 2148: 1695: 1572: 1053: 912: 772:

In 1985, a television camera was used to see the interior of the damaged reactor. In 1986,

613: 601: 586: 534: 482:(120,000 L) of coolant had already leaked from the primary loop. It was not until 6:45 386: 318: 8: 10042: 9980: 9968: 9865: 9399: 9387: 9349: 9119: 9061: 8908: 8764: 7352: 5403:"NRC Approves Vogtle Reactor Construction – First New Nuclear Plant Approval in 34 Years" 4662: 2920: 2813: 1978: 751: 734: 269: 179: 8566: 6926: 6352:"Peach Bottom, other U.S. nuclear power plants could be running until 2054. Is it safe?" 6302: 6184: 5864: 5471: 5314: 5187: 2217: 2031:

Poisoned Power: The Case Against Nuclear Power Plants Before and After Three Mile Island

624:

The release occurred when the cladding was damaged while the PORV was still stuck open.

9738: 9540: 9044: 8672: 8635: 8572: 7180: 6983:"'Meltdown: Three Mile Island' Is a Methodical Look at an American Disaster: TV Review" 5826: 5801: 5734: 5682: 5657: 5613: 5326: 5195: 4692: 4448: 4435: 4415: 4391: 2350: 2276: 2251: 2183: 2129: 2078: 2061: 1464: 1010: 879: 590: 546: 325:

and stopping the heat generated by fission. However, the reactor continued to generate

4416:"Reply to comments on 'A reevaluation of cancer incidence near the Three Mile Island'" 1839:

A revised International Nuclear and Radiological Event Scale (INES) extends its reach.

1514:

destruction from a battle between the characters Wolverine, Sabretooth, and Deadpool.

9890: 9855: 9817: 9339: 8774: 8737: 7953: 7465: 7394: 7282: 7248: 7225: 7206: 7145: 7141:

TMI 25 Years Later: The Three Mile Island Nuclear Power Plant Accident and Its Impact

7124: 7084: 7065: 6861: 6821: 6631: 6396: 6032: 5978: 5948: 5876: 5851: 5831: 5726: 5687: 5605: 5537: 5330: 5199: 4993: 4955: 4842: 4696: 4684: 4557: 4516: 4478: 4453: 4396: 4345: 4304: 4300: 4267: 4124: 4036: 4009: 3999: 3919: 3892: 3882: 3808: 3767: 3708: 3670: 3636: 3602: 3565: 3527: 3484: 3445: 3368: 3298: 3262: 3218: 3174: 3132: 3030: 2992: 2954: 2888: 2851: 2826: 2818: 2776: 2734: 2633: 2595: 2500: 2463: 2342: 2281: 2229: 2175: 2121: 2083: 1959: 1739: 1493: 1123: 1119: 1040:. In the previous May, an estimated 65,000 people—including California Governor 690: 652: 558: 423: 341: 183: 171: 159: 86: 7339: 7081:

Three Mile Island: The Meltdown Crisis and Nuclear Power in American Popular Culture

6519: 5738: 5617: 5352: 3061:(Report). The Essex Corporation. U.S. Nuclear Regulatory Commission. pp. 12, 13 2354: 2187: 2133: 1851: 1767:

Three Mile Island: a report to the commissioners and to the public. Volume II Part 2

1001: 170:. The reactor accident began at 4:00 a.m. on March 28, 1979, and released 9922: 8660: 7159: 7036:(Documentary), Lynne Bernabei, Linda Braasch, Joyce Corradi, Three Mile Productions 6417:"Exelon Generation Formally Integrates AmerGen Assets Into Exelon Nuclear – Exelon" 6310: 6306: 6188: 6171: 5868: 5821: 5813: 5718: 5677: 5669: 5597: 5529: 5475: 5318: 5191: 5086: 5059: 4676: 4443: 4427: 4386: 4378: 4296: 4116: 3437: 3360: 3254: 3210: 3124: 2334: 2271: 2263: 2221: 2167: 2113: 2073: 1945: 1731: 1480:) secretly film a major accident at a nuclear power plant while taping a series on 1029: 726: 415: 258: 151: 7105: 6840: 5494: 5428: 4086: 4062: 3969: 3945: 3084: 2664: 793: 717:) of uranium flowing to the bottom head of the pressure vessel, forming a mass of 215:

activists expressed worries about regional health effects from the accident. Some

10072: 10006: 9988: 9461: 9101: 9091: 9039: 8275: 8270: 7346: 7335: 7324: 7312: 7274:

TMI web page from the US Department of Energy's Energy Information Administration

7194: 5894: 5872: 5601: 3169:. Berkeley, California; London, England: University of California Press. p. 2402: 2250:

Hatch, M. C.; Wallenstein, S.; Beyea, J.; Nieves, J. W.; Susser, M. (June 1991).

2225: 2117: 1675: 1477: 1319:

U.S. 96th Congressional session passed U.S. legislation establishing a five-year

1204: 1089: 871: 834: 396: 216: 6591:"Three Mile Island Nuclear Plant To Close, Latest Symbol Of Struggling Industry" 5849:

Carter, Luther J. (April 13, 1979). "Political Fallout from Three Mile Island".

5562: 5479: 2199: 2197: 9404: 9081: 8799: 8666: 8625: 7112: 6689:"Three Mile Island Unit 2 (TMI-2) Enters Next Phase of Decommissioning Project" 6148: 6057: 4222: 3786: 1522: 1170: 1131: 1076: 997:

List of anti-nuclear groups in the United States § Three Mile Island Alert

701: 686: 550: 349: 281: 201: 9427:

Solar Photovoltaic Energy Research, Development, and Demonstration Act of 1978

6688: 6121: 5500:. Palo Alto, California: EPRI (Electric Power Research Institute). p. 8-1 2830: 2139:

cancer incidence beginning in 1990. These findings, however, do not provide a

2003: 966:

where the reactor was located) and in high-risk age groups but did not draw a

232:

losses. It is expected to go back into service by 2028 as part of a deal with

46: 10124: 10094: 9689: 7451: 7438: 7412:

Report Of The President's Commission On The Accident at Three Mile Island.pdf

7222:

El síndrome nuclear. El accidente de Harrisburg y el riesgo nuclear en España

6888:"'Meltdown: Three Mile Island' Unpacks the Worst Nuclear Incident in America" 6865: 5523: 5495:"The Cleanup of Three Mile Island Unit 2 – A Technical History: 1979 to 1990" 5429:"The Cleanup of Three Mile Island Unit 2 – A Technical History: 1979 to 1990" 5322: 4688: 4161: 4110: 4040: 3923: 3431: 3354: 3248: 3204: 3118: 3058: 2822: 2194: 1998: 1721: 1586: 1489: 1481: 1056:

alleging that the accident caused detrimental health effects was rejected by

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Three Mile Island: A report to the Commissioners and to the Public, Volume I

5706: 5656:

Wing, S.; Richardson, D.; Armstrong, D.; Crawford-Brown, D. (January 1997).

5525:

Three Mile Island: a report to the commissioners and to the public. Volume I

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Three Mile Island: a report to the commissioners and to the public. Volume I

4013: 3896: 3433:

Three Mile Island: a report to the commissioners and to the public. Volume I

3356:

Three Mile Island: a report to the commissioners and to the public. Volume I

3250:

Three Mile Island: a report to the commissioners and to the public. Volume I

3206:

Three Mile Island: a report to the commissioners and to the public. Volume I

3120:

Three Mile Island: a report to the commissioners and to the public. Volume I

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while taking measurements. Houser had noted the sample he drew looked "like

10060: 10054: 9885: 9262: 8882: 8742: 8688: 8683: 7978: 7414:– Report Of The President's Commission On The Accident at Three Mile Island 7398: 7100:

The Cleanup of Three Mile Island Unit 2 – A Technical History: 1979 to 1990

6959: 6235: 5880: 5835: 5777: 5730: 5609: 5203: 5171: 4890:

Lessons Learned From Hydrogen Generation and Burning During The TMI-2 Event

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TMI1 was not operating because it had been shut down for routine refueling.

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Containment steam vented to the atmosphere in order to stabilize the core.

740: 682: 605: 573: 566: 419: 314: 285: 8386:

Nuclear and radioactive disasters, former facilities, tests and test sites

6955:"Dodged a Bullet: How Whistleblowers Averted a Second US Nuclear Disaster" 5691: 5622:

These findings, however, do not provide a causal link to the TMI accident.

4457: 4400: 4308: 4115:. Washington, D.C.: U.S. Nuclear Regulatory Commission. pp. 25, 153. 3085:"Pressurized Water Reactor B&W Technology Crosstraining Course Manual" 2285: 2267: 2087: 1122:

was later asked to tell Congress why naval nuclear propulsion (as used in

10087: 10066: 9833: 9728: 9147: 8814: 7418:

Report of the President's Commission on the Accident at Three Mile Island

7175:, Special Inquiry Group. Archived from the original on November 30, 2010. 7031: 6908: 5174:; Barnes, Kent (June 1982). "Evacuation behavior and Three Mile Island". 3993: 3876: 3807:. Berkeley, California: University of California Press. pp. 90, 91. 3564:. Berkeley, California: University of California Press. pp. 80, 81. 3359:. Washington, D.C.: U.S. Nuclear Regulatory Commission. pp. 17, 18. 3253:. Washington, D.C.: U.S. Nuclear Regulatory Commission. pp. 16, 17. 1544: 1472:

of an entire industry". In the film, television reporter Kimberly Wells (

1395:

NRC issued a safety evaluation report and granted the license amendment.

1181: 1174: 1111:

Report of the President's Commission on the Accident at Three Mile Island

1041: 1025: 979: 801:, near the plant, describing the accident and the evacuation of the area. 773: 516: 511:, and less than 30 minutes later station manager Gary Miller announced a 223:

in and around the area since the accident did determine that there was a

6854:"Review: With 'Heat and Light,' Jennifer Haigh Drills Below the Surface" 5817: 5673: 4382: 3669:. Berkeley, California: University of California Press. pp. 84–86. 3635:. Berkeley, California: University of California Press. pp. 80–84. 3601:. Berkeley, California: University of California Press. pp. 80–84. 3297:. Berkeley, California: University of California Press. pp. 76–77. 3123:. Washington, D.C.: U.S. Nuclear Regulatory Commission. pp. 14–15. 2953:. Berkeley, California: University of California Press. pp. 73–74. 1263:

TMI-2 accident occurred. Containment coolant released into environment.

854: 471:

coating of previously-molten material on bypass region interior surfaces

10018: 9298:

Financial Institutions Regulatory and Interest Rate Control Act of 1978

8804: 7372: 6028:

The Woman who Knew Too Much: Alice Stewart and the Secrets of Radiation

5722: 5434:. Palo Alto, CA: EPRI (Electric Power Research Institute). pp. 1–4 4439: 2338: 2171: 1532: 1473: 1419:

The Advisory Panel for Decontamination of TMI-2 held its last meeting.

1304: 1057: 1028:. The New York rally was held in conjunction with a series of nightly " 1021: 874:

and post-crisis analysis with conclusions of potential overcapacity in

744: 705: 597: 488: 406: 326: 175: 5541: 4680: 4128: 3449: 3372: 3266: 3222: 3136: 2887:. Washington, D.C.: U.S. Government Printing Office. pp. 90, 91. 2850:. Washington, D.C.: U.S. Government Printing Office. pp. 46, 47. 2062:"Cancer near the Three Mile Island Nuclear Plant: Radiation Emissions" 1743: 1044:—attended a march and rally against nuclear power in Washington, D.C. 291: 9471: 8596: 7408:– A growing collection of over 300 songs inspired by the TMI accident 6378:"Like Three Mile Island, Talen Energy's nuclear plant under pressure" 5655: 5528:. Washington, D.C.: U.S. Nuclear Regulatory Commission. p. 153. 5210: 5091: 4954:. Berkeley, California: University of California Press. p. 210. 4556:. Berkeley, California: University of California Press. p. 231. 4515:. Berkeley, California: University of California Press. p. 210. 1642: 1280: 710: 666: 390: 363: 233: 9422:

Nuclear Safety, Research, Demonstration, and Development Act of 1980

7290:, a nuclear watchdog group founded two years before the TMI accident 6193: 6166: 5533: 5083:

Department of Energy, Office of Scientific and Technical Information

4780:"TMI Assessment (Part 2) – Releases of radiation to the environment" 4431: 4120: 3766:. Berkeley, California: University of California Press. p. 89. 3707:. Berkeley, California: University of California Press. p. 87. 3526:. Berkeley, California: University of California Press. p. 79. 3483:. Berkeley, California: University of California Press. p. 78. 3441: 3436:. Washington, D.C.: U.S. Nuclear Regulatory Commission. p. 19. 3364: 3258: 3214: 3209:. Washington, D.C.: U.S. Nuclear Regulatory Commission. p. 16. 3128: 2733:. Berkeley, California: University of California Press. p. 73. 2499:. Berkeley, California: University of California Press. p. 72. 2462:. Berkeley, California: University of California Press. p. 71. 2034:(Updated ed.). Emmaus, Pennsylvania: Rodale Press. p. xvii 1735: 8467: 7421: 6712:"Three Mile Island is reopening and selling its power to Microsoft" 4206: 2406: 1773:. Washington, D.C.: U.S. Nuclear Regulatory Commission. p. 309 1485: 1203:

In 2020 the site was purchased by TMI-2 solutions, a subsidiary of

943: 427: 277: 7102:. Palo Alto, California: EPRI (Electric Power Research Institute). 5050:

Hopkins, A. (2001). "Was Three Mile Island a 'normal accident'?".

4477:. Berkeley, CA: University of California Press. pp. 209–210. 619: 249: 178:

into the environment. It is the worst accident in U.S. commercial

7958: 7380:"Three Mile Island: The Most Studied Nuclear Accident in History" 6449: 2991:. Washington, D.C.: U.S. Government Printing Office. p. 44. 1580: 1540: 1536: 1197: 1116: 947: 523:, which in turn contacted state and local agencies, Pennsylvania 4992:. Washington, D.C.: U.S. Government Printing Office. p. 7. 2672:

Pressurized Water B&W Technology Crosstraining Course Manual

2300:"Backgrounder on the Three Mile Island Accident: Health Effects" 895: 498: 8851: 7293: 7138:

Osif, Bonnie A.; Baratta, Anthony; Conkling, Thomas W. (2004).

2140: 1109:

After the TMI incident, President Carter commissioned a study,

967: 228: 7359:

Three Mile Island – Failure Of Science Or Spin?, Science Daily

6565:"Three Mile Island Power Plant May Close in Face of Cheap Gas" 4087:"Transcript of TMI investigation interview of P Velez, Met Ed" 3970:"Transcript of TMI investigation interview of P Velez, Met Ed" 1462:

On March 15, 1979, twelve days before the accident, the movie

1135:

key one will not work. Each element depends on all the others.

397:

Partial meltdown and further release of radioactive substances

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