Watts Bar Unit 2, last old reactor of the 20th century: a cautionary tale

More than four decades after construction began in 1973, the Tennessee Valley Authority (TVA) is finally getting close to starting up the Watts Bar Unit 2 nuclear reactor. Only final tests stand in the way of it receiving an operating license from the Nuclear Regulatory Commission (NRC). While the TVA and the nuclear industry describe Watts Bar 2 as “the first new nuclear generation of the 21st Century,” in fact the TVA resuscitated a demonstrably unsafe 1960s-era ice condenser design that was abandoned decades ago by the rest of the nuclear industry. Mismanagement and construction problems have driven the project’s price tag up with billions of dollars in cost overruns. Safety continues to be compromised as the NRC is allowing the TVA to delay post-Fukushima seismic design upgrades indefinitely. Rather than exemplifying a fine technological achievement, the history of Watts Bar Units 1 and 2 is a cautionary tale of the worst pitfalls of nuclear power and the federal regulatory system.

This pair of nuclear reactors has a unique distinction. Back in 1996, Watts Bar Unit 1 was the last reactor completed in the United States, at a hefty $6.8 billion. No other reactors have come online since. In fact, according to the NRC, eight US reactors have permanently shut down since Watts Bar 1 was licensed.

Now, Watts Bar 2 is poised to become the next operational reactor in the United States. When Watts Bar 2 comes online, the TVA will be generating almost 40 percent of its power from seven nuclear reactors along the Tennessee River: the two at Watts Bar, near Spring City, Tennessee; two more ice condenser reactors at Sequoyah, near Chattanooga; and three General Electric Mark 1 boiling water reactors at their Browns Ferry plant (using the same design as Fukushima Daiichi), near Decatur, Alabama.

Watts Bar 2 comes from a federally owned utility that has a history of delays, problems, and fiscal irresponsibility when it comes to nuclear power. This history raises the question of why Watts Bar 2 has survived such a long time and whether it should ever be allowed to open. It is a saga of delays and cost overruns, antiquated designs, inadequate quality control and oversight, failure to implement post-Fukushima upgrades, and a deficient safety culture, among other problems—all at a time when there is still no place for long-term storage of the nuclear waste that will be generated. And because the TVA manufactures tritium for use in America’s nuclear weapons, there will inevitably be greater releases of tritium into the air and water of the region—natural resources which already receive four times as much tritium as originally expected.

Ironically, Watts Bar 2 comes when the large-scale development of new, truly clean energy sources is a burgeoning reality. Created as an innovative model for the nation in the 1930s, the Tennessee Valley Authority has become an entrenched, top-down bureaucracy wedded to the past by its continuing embrace of nuclear and other polluting energy sources in the 21st century.

Schedule delays and cost increases. Watts Bar Unit 2 has the longest construction history of any reactor in the world. The cost of completing the reactor has ballooned since an initial estimate of approximately $825 million for both reactors to be online in 1977. By 1985, when the TVA mothballed Unit 2 after more than a decade of construction,the reactor was approximately 60 percent complete and $1.7 billion had been spent. When the TVA resumed construction in 2007, the cost estimate for finishing the reactor by 2012 was $2.5 billion. In 2011, the TVA moved the completion date back to 2015 and added a further $1.5 to 2 billion to its cost estimate.

The Tennessee Valley Authority now tallies the cost of completing Watts Bar 2 to be about $4.4 billion. Add the $1.7 billion sunk into the project before 1985 and Watts Bar 2 will cost about $6.1 billion. The combined Watts Bar project cost of almost $13 billion is nearly 16 times the original projection, not including the interest on the construction debt.

Let us look at some of the reasons for the delays and overruns in turn.

Problematic, antiquated design. Despite having undergone significant recent (re)construction work, Watts Bar 2 is an old reactor design. Both of the Watts Bar 1100-megawatt units were built to the antiquated “ice condenser” containment design that has not been used for any other reactor construction in decades.

The Westinghouse Ice Condenser Pressurized Water Reactor (PWR) was designed in the 1960s. Ice condensers deploy about 2 million pounds of chipped ice hanging in long, skinny baskets around the reactor core in an ice room. The theory—never tested in the real world for obvious reasons—is that in a loss of coolant accident the ice would lessen the excess temperature and pressure created by a meltdown. This flawed logic convinced the Atomic Energy Commission (predecessor to the Nuclear Regulatory Commission) to initially license the design with a less costly, smaller, weaker containment structure, often referred to as “eggshell-like” containment. The driving design goal was lower cost. It was not realized until later that safety had been seriously compromised; a report by Sandia National Laboratories in April 2000 concluded that "… ice condenser plants are at least two orders of magnitude [100 times] more vulnerable to early containment failure than other types of PWRs."

The ice condenser design is the analog to the water-filled torus design employed at Fukushima and the boiling water reactors with Mark I and II containments (29 of which operate in the United States), writes Dave Lochbaum of the Union of Concerned Scientists.

The ice condenser and water-filled torus containments are called "pressure suppression containments." Rather than using a large volume to absorb the energy released during an accident, pressure suppression containment uses water (in the form of ice in this case) to act as energy sponges. The water absorbs heat, reducing the energy remaining to pressurize the containment volume. As a result, the containment need not be as large (or as costly, the prime factor).

Fukushima revealed the glaring vulnerability of such pressure suppression designs—What happens when the sponge gets saturated? At Fukushima, the water in the torus heated to boiling. It could absorb no more energy. The containment over-pressurized and forced hydrogen out. That hydrogen detonated, three times.

The same holds true in the ice condenser design when the ice melts; it cannot absorb any more energy and the relatively small containment volume is vulnerable to over-pressurization failure.

In the 1970s, well-founded concerns about the ice condenser design’s ability to contain radiation in a serious loss of coolant accident resulted in an Atomic Energy Commission staff recommendation to rescind licensing for the design. The commissioners rejected this warning. After the Three Mile Island meltdown and the Chernobyl explosion, a 1990 NRC study, NUREG-1150, found ice condenser reactors to be the most likely to suffer catastrophic containment failure. Watts Bar 2 will be the tenth ice condenser to operate in the United States; the nine operating ones have been plagued with many problems over the years.

Post-Fukushima, the NRC ordered the owners of Mark I and II containments in the United States to mitigate some of the shortcomings. But the NRC did not revise its regulations so as to ensure that future builders of pressure suppression containment avoided replicating the problems. Their reasoning: none of the advanced reactor designs that have been certified or are being proposed feature pressure suppression containments. “It was a good idea on paper that really did not work in practice and has been retired,” says Lochbaum.

There is wide agreement that no more will ever be built. 

None operate outside the United States.

Quality control concerns at Watts Bar. The age and quality of the work done at Watts Bar in the 1970s and 1980s is a major concern. Inadequate quality control and failure to meet NRC construction standards were so serious that issuing the operating license for Unit 1 was delayed for eleven years after construction was complete, while known deficiencies were addressed. The possibility of construction defects deteriorating further over time to create unknown serious problems is a troubling uncertainty. Irreplaceable structural materials and components from the 1970s would be approaching 100 years old if Unit 2 is allowed to operate to the full extent of the industry-advocated 60 years.

An example of the TVA’s problematic oversight of the Watts Bar 2 project is its relationship with the Bechtel Corporation. TVA decision to finish Unit 2 in 2007 relied upon Bechtel’s feasibility study which concluded that the reactor could be completed for $2.5 billion and finished by 2012. In a stunning ignorance of the obvious conflict of interest, the TVA then awarded the construction contract to Bechtel. (In 2011, the Tennessee Valley Authority admitted that the project would cost up to $4.5 billion with a projected finish in 2015, and took control of the project back from Bechtel). At that time, former TVA CEO Tom Kilgore said the increase would not affect ratepayers.

Post-Fukushima design upgrades postponed. In the aftermath of the 2011 Fukushima disaster in Japan, the NRC’s high-level Near-Term Task Force advised the NRC Commissioners to order licensees to reevaluate the seismic and flooding hazards at their sites against current NRC requirements and guidance—and, if necessary, to update the designs and safety systems to protect against the updated hazards. The Task Force also recommended that this effort be completed for Watts Bar 2 before licensing of the reactor. Subsequently, the TVA found that the earthquake risk to Watts Bar 2 exceeds the reactor’s design but the NRC’s commissioners decided that it was not necessary to fully address these risks before licensing Watts Bar 2. They later rebuffed a request by the Southern Alliance for Clean Energy to reconsider its decision.

TVA’s history and mindset—a story of clashes with the NRC. President Franklin Roosevelt created the Tennessee Valley Authority in 1933 as a federally owned corporation. It has since become the nation’s largest public power provider. Founded to help the region deal with serious environmental, economic, and technological problems including inadequate electrification, it was—and still is—a federally protected monopoly. It is no longer funded by the Federal budget but from its own revenue of $11 billion from the sale of electricity to over 9 million people and businesses in parts of seven states.

The TVA’s first major energy source was hydroelectric power from the series of dams it built across the valley for flood control. Next, coal-fired generation became a major electricity source. Battles with the Environmental Protection Agency over toxic emissions eventually encouraged the TVA to go big into nuclear power.

In the late 1960s and 1970s, the TVA started construction on 17 reactors. Ten reactors were abandoned in the 1980s, leaving the TVA with tens of billions of dollars in debt and ratepayers saddled with multiple rate increases. (Watts Bar Unit 2 will be the TVA’s seventh operational reactor.) But two of those “abandoned” reactors, Bellefonte Units 1 and 2, still have deferred licensing status. These zombie reactors will cost the TVA $53 million in 2016, despite no plans to complete them.   

The early history of the Tennessee Valley Authority’s nuclear program was plagued with problems. They include many clashes with the NRC, safety lapses, huge cost overruns, and construction problems, from the notorious “candle fire” at Browns Ferry Unit 1 near Decatur, Alabama in 1975 to the complete, albeit temporary, shutdown of the utility’s nuclear program in 1985. (The 1975 fire was started by a worker with a candle checking for air leaks into the Browns Ferry Units 1 and 2 control room. The fire burned for more than seven hours; many cables and electrical boards were lost, including almost all emergency core cooling systems. A double meltdown was narrowly averted.)

And the safety culture at the TVA has been stubbornly resistant to remediation for decades: Browns Ferry was under a “red safety finding”—in which a problem was determined to have high safety significance, resulting in increased NRC inspections—after a crucial 600-pound emergency cooling system valve was found in 2010 to have been inoperable since it was installed in the late 1960s. Incredibly, the plant has still not met the NRC’s enhanced fire safety regulations, which were prompted by the candle fire decades earlier. In May of 2012, the NRC granted the TVA’s request for more time to submit its plan to comply; compliance will not come before 2016, if then. Enhanced regulations include separating backup and primary control cables for emergency safety systems, and separating the plant into different fire zones. 

A possibly related problem is the TVA’s history of nuclear whistleblower harassment, discrimination, and retaliation; Watts Bar and Sequoyah were in the top five for 2012 NRC whistleblower complaints. (Watts Bar had 21, Sequoyah 19, and Browns Ferry 16.) The most recent example was at Browns Ferry in 2013, when the engineer completing the analysis for the root cause of the red finding and another report on software problems was harassed for refusing to weaken her report’s findings.

And at the same time, the Watts Bar 2 reactor will face the same issue that all reactors face in the United States: No place to permanently store the nuclear waste.

More reactors, more nuclear waste. All commercial power reactors in the United States, whether operating, shutdown, or decommissioned, store their highly radioactive, long-lived nuclear waste (or  “spent fuel”) on-site. It will remain there for decades, centuries, or potentially forever. Highly irradiated used fuel must be isolated from the environment for hundreds of thousands of years.

In the realm of nuclear power, the only thing that has taken longer to finish than Watts Bar 2 is the still unsolved problem of what to do with high-level radioactive waste. With the operation of the new reactor, more nuclear waste will be produced, piling up near the Tennessee River.

And more radiation will be finding its way into the river’s waters as well.

Watts Bar and nuclear weapons. Of the ongoing radioactive releases from nuclear power plants both during “normal” operation and accidental releases, tritium has been one of the most troubling and persistent. Tritium is radioactive hydrogen; it combines with oxygen to create tritiated water. Hydrogen is extremely difficult to contain due to its low molecular weight. Consequently, tritium is released into the air and water in many different ways: through the cooling water outfall; via steam purposely released out of the cooling towers; and unintentionally released through broken pipes, valves, and tanks. At Watts Bar Unit 1, the TVA manufactures extra tritium for use in United States' nuclear weapons; this resulted in tritium releases that are four times higher than originally expected. The Tennessee Valley Authority is planning to increase the military production of tritium by over 100 percent in Unit 1. The startup of Unit 2 will further increase tritium releases into the air and the Tennessee River—the water supply for many downstream communities, including Chattanooga. In his 2002 book, Tritium on Ice, Kenneth D. Bergeron—formerly of Sandia National Laboratories—delves deeply into this troubling connection.

Given the expected increase in radioactive releases, a recommendation was made to the NRC Commissioners at the Watts Bar 2 briefing in October 2014 that the NRC should require the TVA to install real-time, on-line radiation monitoring and other measures to “make radiation visible” at Watts Bar and all the other operating nuclear facilities. With the advances in monitoring and communications technology since 1973 and the increase in the understanding of the dangers of radiation, this should be implemented before Watts Bar 2 begins operation. Unfortunately, this request has been ignored.

A safer, less risky future is possible. Ratepayers, utilities, and regulators should heed this cautionary tale, whose lessons are only reinforced by recent efforts to build ever more costly and delayed new reactors here in the United States, including SCANA’s V.C. Summer reactor in South Carolina, and the Southern Company’s Plant Vogtle reactors in Georgia. (And abroad at Flamanville, France; Olkiluoto, Finland; and Hinkley Point, Great Britain.) New nuclear power generation is turning out to be the failed technology of the 21st century.

During Watts Bar Unit 2’s more than forty-year long journey to completion, renewable energy and energy efficiency have undergone revolutionary advances and cost reductions. Renewables are growing worldwide at increasingly rapid rates as costs plummet; by way of example, the cost of solar panels has dropped by 80 percent in the past five years. And the TVA currently is being offered 3500 megawatts of wind power from Oklahoma from Clean Line Energy Partners at a very competitive cost. This revolution undermines any justification of the risk, environmental harm, cost, and proliferation issues of nuclear power. Without the need for nuclear power, Iran and other countries that covet nuclear weapons would have no justification to enrich uranium and no “cover” to hide their nuclear weapons aspirations.

Advances in renewable energy technologies and energy efficiency have created the reality of an exciting, truly clean energy future. Nuclear power is not needed to mitigate global climate change. The TVA’s experience has shown how difficult it is to integrate 1000-megawatt power sources into an unpredictable future energy supply and how expensive nuclear projects drain a utility of the finances needed for creating the 21st century energy mix we desperately need.

Unfortunately, the TVA’s love affair with nuclear power continues unabated. The Tennessee Valley Authority refuses to officially terminate the licenses for Bellefonte reactor Units 1, 2, 3, and 4, despite having no plans to finish them. And the TVA is still pursuing a controversial small modular reactor program, despite very unfavorable market conditions. The TVA has even asked the Nuclear Regulatory Commission to allow it to coax 20 percent more power out of the old, troubled Browns Ferry reactors.

All the while, the TVA has been limiting measures to increase energy efficiency, expand storage, and grow the use of renewable resources. Instead of leading, the TVA is falling farther behind in the transition to a 21st century energy system. Unfortunately, the organization’s top brass have not yet begun to heed the advice of its former board chairman, S. David Freeman, who in 2013 admonished them: “TVA’s talented leaders must seize the opportunity to stop pouring billions into yesterday’s dirty and dangerous power plants.”

As the old saying goes, “Those who refuse to learn from history are doomed to repeat it.” Unfortunately for residents and TVA customers in the Valley, they will again be forced to pay for the Tennessee Valley Authority’s repetitive, losing choices—in more ways than just through their monthly power bill.

Editor's note: The article’s authors collaborated in a briefing on the status of Watts Bar 2 to the US Nuclear Regulatory Commissioners on October 30, 2014.