On-Site, MRS, Geologic Storage

Spent nuclear fuel is presently stored on site at 65 reactor facilities around the country. Held in large pools of water, these storage facilities are filling up and need to either be expanded at substantial cost, or an alternative storage plan needs to be implemented. The three candidate solutions to this problem are on-site storage, an MRS facility, or geologic storage at the Yucca Mountain repository. It is likely that a combination of these approaches will eventually make up the nation's nuclear waste disposal program.

No matter how the battle over Yucca Mountain turns out, the nation is still faced with the question of how and where to store 30,000 tons of nuclear waste already created and 40,000 tons in the pipeline. Even the critics of Yucca Mountain have never seriously questioned the need for geologic storage of the waste, they have only contended that the timing is inappropriate and that present technology is inadequate. Thus, on-site storage is suggested only as a temporary solution, although it is often presented to the public as a long term remedy.


Because of the likelihood that neither a geologic repository nor an interim Monitored Retrievable Storage site will be available by the deadlines imposed by the Nuclear Waste Policy Act, the Nuclear Regulatory Commission looked at the question of whether spent fuel could be kept on site for periods up to 100 years. The NRC's finding that this would be safe, although not necessarily advisable, left an opening for opponents of Yucca Mountain to argue there is no rush to build a geologic repository.

Environmentalists coordinated by Nader's Safe Energy Communication Council have long proposed that nuclear spent fuel assemblies could be left on site at various reactors around the nation in large "dry cask" units until a better solution was derived. The environmentalists hope that in thirty or forty years, science will have advanced to the point where our knowledge of how to build underground geologic storage will be vastly superior, at which point we could presumably proceed with building a repository. This does not address whether the expertise now available could be orchestrated forty or fifty years into the future.

The Nevada Nuclear Waste Project Office has also adopted this on-site storage option, often citing a study by researchers at the Institute of Safety and Systems Management at the University of Southern California.

An alternative that looks like it potentially possesses many desireable characteristics is to establish an endowment at the current time to provide the financial resources 100 years from now to manage the spent nuclear fuel that would be stored between now and then in dry storage facilities at the sites of nuclear power plants. The base case analysis suggests that the on-site facility with a $6 billion fund for the future is better by the equivalent of at least $20 billion than the monitored retrievable storage facility and $30 billion better than a repository. With on-site storage and a $3 billion fund, the equivalent costs are at least $10 billion better than the monitored retrievable storage facility and $21 billion better than the repository. [Keeney, Ralph; von Winterfeldt, Detlof; "An Analysis of Strategies to Manage Nuclear Waste from Power Plants", Institute of Safety and Systems Management, USC, Report 93-1, p82]

Whether or not the Keeney and von Winterfeldt economic analysis was correct, there should be some concern that it is possible to keep a fund with $3 to $20 billion in funds inaccessible to the political establishment. A similar fund supported by highway taxes was recently usurped by Congress.

Interestingly, the anti-nuclear lobby has in effect admitted that its position favoring on-site storage is a sham meant to diminish support for geologic storage at Yucca Mountain rather than offer a viable solution. Attempts to store waste in 17 on-site casks at the Prairie Island nuclear powerplant near Red Wing Minnesota are also opposed by environmental activists:

Storage Of Nuclear Wastes Fuels A Debate

In what is seen as a test case for other states, Minnesota is giving a new lease on life to a nuclear power plant that is running out of storage space for its radioactive waste. . . .

Without the temporary storage, the Red Wing, Minn., plant would have been forced to close one reactor next May and the other in early 1996 - eliminating 500 jobs, raising electricity rates and straining demand on other utilities.

It was the first time a plant threatened to close because it lacked temporary nuclear waste storage capacity.

I'm acutely aware of the problem," says Energy Secretary Hazel O'Leary, a former Northern States Power executive. "Even if a plant shuts down, you have to do something with the waste."

By the year 2000, she says, 32 plants in 21 states will need similar above-ground storage. By 2010 - the soonest a federal site may be open - almost half of the nation's 108 plants will have run out of space. . . .

Among those opposed: Prairie Island Mdewakanton Dakota Indians, whose reservation is next door. The tribe fears the casks will become permanent, creating health risks.

Though Prairie Island has a good safety record, it is "putting off the inevitable" by using temporary storage, says Michael Mariotte, Nuclear Information and Resource Service. USA Today, Monday, May 9, 1994 p 7A.

Both the National Resource and Information Service and the Sierra Club have actively opposed the Prairie Island on-site storage site, both of whom are active members of the Safe Energy Communication Council. Consequently, these groups favor on-site storage when speaking to Nevadans, but oppose it when speaking to Minnesotans.

Fortunately, the Mdewakanton Indians recognized the problem with this strategy, as have other stakeholders in nuclear states. Without a permanent storage site, such as Yucca Mountain, states could face indefinite storage of nuclear waste on-site, at best in storage casks and at worst in spent-fuel pools. The long term radiation risks from such scenarios is itself substantial.


An option intermediate to on-site storage and geologic storage is to build one or more aboveground temporary storage and handling facilities as part of a Monitored Retrievable Storage system. These sites would act as collection and processing centers for nuclear waste, perhaps doing the final preparation of the casks for final disposal below ground.

One possible advantage of an MRS facility is that spent fuel cools with time (an advantage in a cold repository design). Another advantage is that a centralized MRS facility would allow standardization of storage and handling technology. Nevertheless, the GAO concluded on the basis of both safety and costs that the MRS solution does not offer significant advantages over a system without an MRS intermediary.

One obvious choice for an MRS facility would be at Yucca Flats at the entrance to Yucca Mountain. The Nuclear Waste Policy Act now prohibits an MRS from being sited in the same state as the repository, however, the act may be amended in 1995.


The concept of geologic repositories goes back to the mid 1950s after the National Academy of Science recommended deep storage. Field studies of salt formations as a possible disposal medium began in the 1960s and with studies in basaltic rocks being added in the 1970s. Studies of the salt beds near Lyons, Kansas in the mid 70s led to embarassment when it was found that nearby commercial drilling for brine had contaminated the area. Drilling in basalt near Hanford, Washington, would have faced severe technological hurdles from severe water flows. A site in Deaf Smith County, Texas, also was below the Ogallala aquifer.

The singular thing about Yucca Mountain and the Nevada Test Site is the great depth from the ground surface to the water table. Consequently, while many consider the choice of Yucca Mountain as a purely political outcome, Yucca Mountain was the only site under study which offered disposal of nuclear wastes in unsaturated rock.


TRANSPORTATION: There is more immediate transportation of nuclear waste using the Yucca Mountain repository instead of on-site storage, but in the long term the waste will still need to be moved. One problem with waiting is the possible decomposition of fuel rod cladding over time, making repackaging more difficult and an accident more likely to spread contamination (pointed out by Marvin Resnikoff).

COOL DOWN PERIOD: While it is true that nuclear spent fuel becomes exponentially safer to handle with time, the waste has already become substantially cooler (both radioactively and thermally) after the five years required before shipment. Moreover, most waste will experience more than ten years wait before being stored at Yucca Mountain given present timetables.

TERRORIST ATTACK: The odds of being able to protect 65 reactor sites from terrorist attack are certainly less promising than protecting a deep geologic disposal site. Dry-casks are extremely robust, however the bombing of the World Trade Center indicates that powerful and sophisticated conventional explosives are available.

SURVEILLANCE: On-site storage requires a significantly larger surveillance effort than associated with a centralized repository. These costs can be prohibitive when a number of sites is factored into the equation. Surveillance would be needed during transportation for both scenarios, although delayed by a number of decades for on-site storage.

INSTITUTIONAL STABILITY: Given present world instability, assuming America will be politically stable 50 to 100 years from now is in itself a risky prediction. Delaying Yucca Mountain increases the risks that a geological repository will never be properly constructed, if it is even built.

HAZARDS TO NEVADANS: While it is true that siting Yucca Mountain in Nevada will expose Nevadans to slightly higher radiation risk (approximately 1 millirem per year for someone within three miles of the site), it is also true that radiation pollution of the American continent could well be higher utilizing the on-site solution. While a Nevadan might be marginally affected long term by Yucca Mountain, their health and safety might be immediately threatened from on-site nuclear waste accidents during their trips to other cities.

TECHNOLOGICAL SOPHISTICATION: On-site, MRS and geologic storage canisters are likely to be patterned after the Multi-Purpose Canister system. Consequently, in a system that utilizes on-site, MRS and geologic storage, the technology for each leg is likely to converge.

RESPONSIBILITY TO FUTURE GENERATIONS: On-site storage and an MRS facility both risk the possibility that nuclear waste will be left aboveground indefinitely. While one can argue that interim on-site storage or the MRS option allow us to take advantage of advances in nuclear waste disposal technology, Yucca Mountain is likely to remain open for 100 years. Consequently, future reconfiguring of the waste is not ruled out even for deep geologic storage.

After analysis, the supposedly superior benefits of dry-cask storage promoted by anti-nuclear advocates become at best equivalent to the Yucca Mountain option. In a rational world, the anti-nuclear forces would be ambivalent about whether on-site or immediate geologic storage was chosen. Instead, their nearly hysterical opposition to geologic storage suggests their motives may be more ideological than measured by technological arguments.