Cover image for TMI 25 Years Later: The Three Mile Island Nuclear Power Plant Accident and Its Impact By Bonnie A. Osif, Anthony J. Baratta, and Thomas W. Conkling

TMI 25 Years Later

The Three Mile Island Nuclear Power Plant Accident and Its Impact

Bonnie A. Osif, Anthony J. Baratta, and Thomas W. Conkling


$34.95 | Paperback Edition
ISBN: 978-0-271-02743-2

194 pages
6" × 9"
30 b&w illustrations

TMI 25 Years Later

The Three Mile Island Nuclear Power Plant Accident and Its Impact

Bonnie A. Osif, Anthony J. Baratta, and Thomas W. Conkling

“The accident at Three Mile Island Unit 2 in 1979 is historically important for understanding the development of nuclear power in the United States. This book is a concise, well-written, documented account of the accident and its cleanup, but it also provides welcome insight into the media coverage and public understanding of nuclear energy matters. With valuable primers on nuclear energy basics and energy options for the future, TMI 25 Years Later is well worth reading by professionals as well as laypersons.”


  • Description
  • Reviews
  • Bio
  • Table of Contents
  • Sample Chapters
  • Subjects
Three Mile Island burst into the nation's headlines twenty-five years ago, forever changing our view of nuclear power. The dramatic accident held the world's attention for an unsettling week in March 1979 as engineers struggled to understand what had happened and brought the damaged reactor to a safe condition. Much has been written since then about TMI, but it is not easy to find up-to-date information that is both reliable and accessible to the nonscientific reader. TMI 25 Years Later offers a much-needed "one-stop" resource for a new generation of citizens, students, and policy makers.

The legacy of Three Mile Island has been far reaching. The worst nuclear accident in U.S. history marked a turning point in our policies, our perceptions, and our national identity. Those involved in the nuclear industry today study the scenario carefully and review the decontamination and recovery process. Risk management and the ability to convey risks to the general population rationally and understandably are an integral part of implementing new technologies. Political, environmental, and energy decisions have been made with TMI as a factor, and while studies reveal little environmental damage from the accident, long-term studies of health effects continue.

TMI 25 Years Later presents a balanced and factual account of the accident, the cleanup effort, and the many facets of its legacy. The authors bring extensive research and writing The authors bring extensive research and writing experience to this book. After the accident and the cleanup, a significant collection of videotapes, photographs, and reports was donated to the University Libraries at Penn State University. Bonnie Osif and Thomas Conkling are engineering librarians at Penn State who maintain a database of these materials, which they have made available to the general public through an award-winning website. Anthony Baratta is a nuclear engineer who worked with the decontamination and recovery project at TMI and is an expert in nuclear accidents. The book features unique photographs of the cleanup and helpful appendixes that enable readers to investigate further various aspects of the story.

“The accident at Three Mile Island Unit 2 in 1979 is historically important for understanding the development of nuclear power in the United States. This book is a concise, well-written, documented account of the accident and its cleanup, but it also provides welcome insight into the media coverage and public understanding of nuclear energy matters. With valuable primers on nuclear energy basics and energy options for the future, TMI 25 Years Later is well worth reading by professionals as well as laypersons.”
TMI 25 Years Later provides a concise and objective overview of the causes and consequences of the Three Mile Island accident. Having played a role in the events the authors describe, I am impressed by their coverage of everything from reactor operation and regulation to effects on the surrounding community and the ten-year cleanup effort. They also do an excellent job of placing nuclear power in a long-term energy perspective.”
“They have produced a very good book not only about TMI but also as an introduction to nuclear power and radiation effects and as a primer on the interaction of the media, the public, and the community in the development of governmental policy. . . . This book will appeal to those interested in TMI, in the general area of energy, and even to those who like a good story.”

Bonnie A. Osif is the Engineering Reference and Instruction Librarian and the Pennsylvania Transportation Institute Librarian at The Pennsylvania State University.

Anthony J. Baratta is Professor of Nuclear Engineering and Head of the Nuclear Safety Center at The Pennsylvania State University.

Thomas W. Conkling is Head of the Engineering Library at The Pennsylvania State University.


Preface and Acknowledgments


1. Nuclear Energy Basics

2. The Accident

3. The Cleanup of TMI Unit 2

4. Media Coverage and Public Understanding

5. The Effect on the Local Community

6. The Impact of Three Mile Island

7. Energy for the Future






For most people in the quiet area surrounding Middletown, Pennsylvania, March 28, 1979, dawned as an unremarkable early spring day. It was Wednesday; the weather was unexceptional. Nothing seemed out of the ordinary. It was a typical day in a pleasant rural and suburban area whose only claim to fame was that it was just outside the state capital, Harrisburg, and near the giant Hershey Chocolate Company complex.

The headline in the local paper, the Harrisburg Patriot, warned: “OPEC Ups Crude’s Price by 9%, Allows Surcharge.” Two additional articles on the front page concerned this worrisome news, while others gave some attention to the Israeli-Egyptian peace talks and several local issues.

Those headlines did not have much of an impact on most readers. Some might have thought, briefly, that rising oil prices would increase their driving costs—if not the cost of heating and lighting their homes. Perhaps the decision to build that reactor on the slim island in the Susquehanna River had been correct: nuclear power might help buffer the costs and insecurity of having so much energy dependence on those distant, somewhat mysterious nations in the Middle East. In any case, there was nothing atypical about the commute to work—many drove to the state capital ten miles away—or the bus rides to school. Radio and television mirrored the Patriot’s coverage of a normal day. The media reported no earth-shattering news, nothing that was going to grab the headlines. Even those reading the big city paper, the Philadelphia Inquirer, saw an interesting but not dramatic headline. A front-page banner announced a major baseball event: Mets pitcher Nino Espinosa had been traded to the Philadelphia Phillies in exchange for the power hitter Richie Hebner. While of great importance to the baseball fans in Philadelphia and New York and good for discussion around the water cooler, the trade’s appearance on the front page clearly indicated what a routine news day it was.

For a few people, one early-morning occurrence was not absolutely normal. Several neighbors on the river near the reactor had awakened to a loud sound at 4:00 AM. They described it as the sound of a jet engine. It was not the first time they had heard this noise, and some knew that it was the sound of steam being vented from the plant. It might be annoying, but it happened some days—a fact of life if you lived near the reactor on the island.

In the Three Mile Island (TMI) Unit 2 control room, however, there were several people who knew, as of 4:00 AM, that Wednesday would not be a typical day. And as the dark night gave way to dawn, they might have realized that it would never be viewed as a normal day again. Many Pennsylvanians, and people across the United States and around the world, would note March 28, 1979, as a pivotal day in history. Exactly how people viewed it changed rapidly as events unfolded. While history has mellowed the view of that day, its importance and far-reaching effects have not lessened.

The first announcement of something gone amiss was reported by Harrisburg radio station WKBO at 8:25 AM. The announcer mentioned a problem at the reactor but explained that there was no danger to the public. At about 9:00 AM, the Associated Press announced that the Three Mile Island nuclear reactor in Pennsylvania had had a general emergency, but the story made clear that no radiation had been released. With this short news report, the public saga of the most serious reactor incident in the United States began. Unit 2 had developed alarming problems in the quiet morning hours. Within a short time, world attention was focused on one reactor located on an island in a little-known river in a relatively unknown area of the country—and on a technology that was poorly understood by the public.

The reactor in the Susquehanna River was one of two plants at the Three Mile Island Nuclear Generating Station. Two reactors with four cooling towers had been built on an island located in a wide, slowmoving part of the river. Unit 1 came online in September 1974 and was down for refueling that day. Unit 2 came online in December 1978, three months before the accident. Owned by Metropolitan Edison Company, Jersey Central Power and Light Company, and Pennsylvania Electric Company and operated by General Public Utilities Nuclear Corporation, the reactors provided energy for northeastern Pennsylvania and New Jersey. There had been protests against the planning and construction of the station, but most people in central Pennsylvania had become accustomed to the four large concrete funnels reaching 370 feet into the sky as part of the everyday skyline. The construction had started eleven years earlier; the towers were visible from the state highways that paralleled the river, from many small streets, and from planes flying out of the nearby Harrisburg airport. They were part of the landscape—a part of modern life. By evening, the landscape looked much the same, but the towers and the other buildings on the narrow island represented a different perspective on modern life, one that was difficult to understand and hinted at a very real danger.

Approximately an hour after the local radio station released the story, the Associated Press reported that the reactor was leaking radiation. Reporters and citizens alike clamored for more information as the Nuclear Regulatory Commission, company representatives, and local government officials went into action. By late afternoon, news reporters were flooding into this largely rural area. Hotels and restaurants were crowded with people who probably had never anticipated spending time in this small town outside of Harrisburg. News coverage was different in 1979 than it is today. Television was limited to the three major networks: ABC, CBS, and NBC. News networks with twenty-four-hour service and easy remote coverage were uncommon. Only a few radio stations broadcast news around the clock; the Internet, with its instant access to facts and rumors, was only a tool of a select group of scientists. The coverage was primitive by today’s standards, and this only served to heighten the drama as more information (some accurate, some less so) trickled out. News conferences were called, and nuclear experts, utility spokespeople, and government officials contributed facts as well as their opinions.

The media tried to understand and interpret information that was new and rather unknown to most of them. There were conflicting stories, and the tone of the coverage varied from station to station. John Herbein, vice president of Metropolitan Edison (which owned and operated TMI), told reporters that there had been minor damage and that small traces of radiation had been released. In the late afternoon, Lieutenant Governor William Scranton told reporters that thesituation was more complex than originally reported but that it represented “no danger to public health.” Citizens and reporters alike were confused. How much of a crisis was there? How much of the area was in danger? Who was at risk? Where were areas of safety? How much time was there to escape should the worst happen? What was the worst that could happen?

Answers to these questions were not always consistent, understandable, or reassuring. Some people packed up and left. Others simply left, not taking the time to pack any of their possessions—partly to save time and partly because they were unsure whether the items had already been contaminated. A day that had started calmly ended in confusion, anger, and fear.

On March 29, as journalists continued to pour into the area, the newspaper headlines were still not overly urgent. The New York Times led with a story entitled “Radiation Is Released in Accident at Nuclear Plant in Pennsylvania.” It was not, however, a banner headline, and the name of the plant was not mentioned until the third paragraph. The Harrisburg Patriot calmly stated, “Radiation Being Vented, Delay in Alert Assailed.” The day after the accident, readers may have been nervous, but they were getting updates on the radio; while the engineers were struggling with the situation, they still seemed in control. Local people took the headlines seriously. While some had vacated their homes and the area around the reactor, most stayed in their homes, and those at some distance from the damaged reactor did not think they had a great deal to fear. Granted, protesters had used this accident as a chance to repeat dire warnings and predictions they had been making for years about the dangers of nuclear energy. Others pointed to a recently released film, The China Syndrome, to explain what might be happening. The high-profile movie starred Jane Fonda, Jack Lemmon, and Michael Douglas; it envisioned a scenario in which the core of a nuclear reactor had been uncovered and had overheated, the molten core melting through the containment building to the ground below. To the average citizen, however, what was happening on the island was a localized story, if somewhat frightening and difficult to understand.

The tone and degree of news coverage changed radically on March 30. The New York Times front-page headline read, “Atomic Plant Is Still Emitting Radioactivity,” and the newspaper ran photographs of children playing in the foreground of a cooling tower and of chemists testing milk produced in the area. Additional stories detailed other aspects of the accident, and the lead editorial addressed “The Credibility Meltdown.” The Philadelphia Inquirer and the Harrisburg Patriot followed suit, with TMI stories dominating their national coverage. If the world had been following news accounts of Three Mile Island with calmness and patience, two announcements would change all that. The first was a miscommunication concerning a release of radioactivity. On March 30, a reading of 1200 millirem was taken above the auxiliary building after a deliberate venting. This reading, however, was reported as having occurred off site, causing fear of a serious radiation leak. The same morning, at approximately 9:50, it was announced that there was a hydrogen bubble in the reactor and that scientists feared an explosion. Suddenly, the world was faced with the unthinkable—a full-fledged nuclear disaster replete with loss of life, devastating health problems, and widespread radioactive contamination. Eyes that had glanced toward Middletown and TMI for two days were now glued to the coverage of that small island in the middle of the Susquehanna River. The nuclear age had entered a new phase, one that endures to this day.

The day of the TMI accident marks a major milestone in U.S. history, a day that shook our faith in science. Suddenly, Americans—and people around the world—realized the need to understand better the new technology and to consider the impact it would have on their everyday lives. They also had to look at their own lives, their families, and their possessions, deciding what was important and what was not. It was a day when operators failed and when manuals did not provide procedures for such an emergency. Technology and technicians, flawed and hard-pressed, were pushed to the limit, and yet they prevailed. It was a day when the media had to consider their lack of preparation in science and technology, subjects that suddenly seemed of utmost importance in modern life. Elected officials had to face the nuclear age in their own backyards. Corporations had to answer questions— not about profit and loss, but about risk-analysis decisions. Twenty-five years have passed since the events at Three Mile Island. Time has eroded some of the drama—especially for those who did not live through those nerve-wracking days—and provided important perspective. Many people know very little about the events that started on that March morning. Hindsight and numerous studies have provided a clear, reasoned view of what actually happened in the reactor. Today we know that there was a partial meltdown of the reactor. Fuel in the reactor overheated because of the lack of cooling water. We know that the radiation released was minor and likely caused no radiation-related health effects. We also know that the events underscored the need for highly trained personnel to operate the plants; for regulators well schooled in the technology they regulate; for a coordinated response by federal, state, and local officials; and, most of all, for an educated press and public that can understand the complex issues associated with modern technology.

This is the story of Three Mile Island and its legacy. To understand fully the incident on March 28, and the days of crisis and years of cleanup that followed, it is necessary to have a working knowledge of the basics of nuclear energy and radiation, to put energy use and production into context, and to look at the way in which these issues are covered by the media (routinely, in educating the public, as well as in times of crisis). Medical, environmental, psychological, and economic issues are important parts of the overall picture, as are other energy technologies. The facts need to be understood—and the rumors and myths put to rest. Both the unbridled promises and the unfounded fears must be put into perspective.

Nuclear energy—with its benefits and its hazards—is a major aspect of our everyday life as we turn on our lights, microwave our popcorn, and sit down in front of our television sets. Our everyday use of energy and our policy decisions concerning fuels, environment, and political alliances have roots in the events of March 28, 1979. Beyond the decisions concerning reactors are the questions that continue to plague us about health, environment, finances, safety, government, and the media’s role in informing the public. The only way to answer these questions, quiet the fears, and provide for rational, considered decisions is to ensure that basic information is made available and understandable to all. Combining this information with historical perspective increases the likelihood that informed decisions can continue to be made by policymakers and the people. Our future depends upon it.

© 2004 The Penn State University

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