The Days of MOX Are Numbered

October 9, 2015 | 5:50 pm
Ed Lyman
Director, Nuclear Power Safety

On Wednesday, the House of Representatives Armed Services Committee hosted the latest installment in the ongoing debate over the fate of the troubled Mixed Oxide Fuel (MOX) Fabrication project at the Savannah River Site (SRS) in South Carolina. It was apparent that the remaining handful of home-state MOX defenders in Congress are losing steam in the face of one withering report after another documenting the mismanagement and waste plaguing the program.

This shouldn’t be a surprise: Even the most shameless pork-barrel politician should be embarrassed to keep asking taxpayers to pony up nearly $1 billion a year for the next 30 years—the amount that nearly all parties agree is the minimum needed to successfully complete the project. Yet even if Congress were to provide full funding today there is no guarantee the money flow would be sustained over decades, given all that could go wrong along the way.

This is why the Department of Energy (DOE), which is the program’s sponsor and strongest advocate for more than a decade, now wants to pull the plug, if only Congress would let it do so.

An alternative to MOX

The MOX program had a noble goal: taking thousands of nuclear bombs’ worth of plutonium produced for the military and converting it into fuel for peaceful nuclear reactors. But MOX’s main problem has always been that it is far cheaper to just throw the plutonium away.

DOE’s preferred approach is to “downblend” the excess plutonium by mixing it with an inert material known as “stardust”and package it as waste for disposal in the Waste Isolation Pilot Plant (WIPP) in New Mexico. As confirmed by the “red team” tasked by DOE Secretary Moniz to take a fresh look at the various options for plutonium disposition, the downblending process is far simpler than MOX, would require much less new capital investment, and has already been used to dispose of several metric tons of excess plutonium.

The red team report estimates that the approach would cost about half as much as the MOX program and would have much less technical risk. This assessment takes into account the fact that WIPP is currently not accepting waste because of the accident that it experienced in February 2014 but is projected to begin operating again by the end of 2016.

However, the less glamorous WIPP disposal option never had the same appeal to many policymakers, who fought to keep MOX as the one and only alternative for plutonium disposition.

The MOX Fuel Fabrication Facility, under construction. (Source: Friends of the Earth)

The MOX Fuel Fabrication Facility, under construction. (Source: Friends of the Earth)

Growing costs of MOX

Today, the situation is this: DOE estimates the total construction cost of the MOX Fuel Fabrication Facility—only one element of the full program—will cost $12-14 billion, approximately 10 times greater than the initial projection. Of this, $4.8 billion has already been spent, implying the project is at most 40% complete.

But this may not present the whole picture because, according to DOE witnesses at the hearing, the remaining work to be done is more difficult. Another complication that emerged at the hearing is the fact that 25% of the support equipment that has already been installed, such as electrical cable trays and piping, will require “re-work,” meaning that it will have to be ripped out and replaced. In fact, at the hearing Rep. Jim Cooper (D-TN) pointed out that in its rush to qualify for fees based on placement of equipment, the contractor placed equipment in areas where it actually blocked access to other equipment, presumably with the knowledge that it would have to be moved again later at additional cost to the taxpayer.

The contractor, CB&I Areva MOX Services, disputes the total cost figure and claims that the plant is nearly 70% complete. As Rep. Cooper  pointed out, “the contractor is supposed to be working for us.” But a spirit of cooperation is not apparent from the behavior of MOX Services, which has launched a rogue campaign to promote its view of the conflict (using whose money, one wonders) and hopefully keep the dollars flowing.

A rogue campaign to support MOX

MOX Services commissioned a supposedly independent assessment from a consulting firm called High Bridge, which produced a thick report criticizing the red team’s conclusions, defending the MOX program and casting doubt on the viability of the WIPP alternative. The report asserts that the red team’s assessment of the WIPP option underestimates (1) the technical risk of relying on WIPP to accept the entire U.S. inventory of excess plutonium; and (2) the political risk of asking for Russia’s consent to change the disposition option that is referenced in the current version of the U.S.-Russia Plutonium Management and Disposition Agreement (PMDA).

There is no question that the February 2014 WIPP accident cast doubt over the safety of DOE’s operations at the site. But one also has to consider the alternatives. If DOE is unable to safely operate what is essentially a fancy hole in the ground for burying nuclear waste, then how can we reasonably expect it to safely oversee the far more complex and hazardous MOX program? In fact, the High Bridge report failed to mention that all nonessential environmental management operations were currently suspended at the Savannah River Site following September 3 near-criticality accident at the HB-Line, a facility being used to produce plutonium oxide for use as feedstock in the MOX plant (should it ever operate), and that SRS does not have a projected date for resuming operations at HB-Line and other facilities that support the MOX programDOE is going to have to up its game no matter what alternative is chosen.

WIPP facility (Source: DOE)

WIPP facility (click to enlarge) (Source: DOE)

And although one shouldn’t underplay the WIPP accident, in which plutonium was released underground from a defectively packaged waste drum, there was far less plutonium release to the environment than could result from an accident at an above-ground facility such as the MOX Fuel Fabrication Facility or at a nuclear reactor using MOX fuel.

High Bridge also harps on the limits of WIPP capacity established by the Land Withdrawal Act, claiming that the legal limit on waste volume would have to be changed to accept the entire inventory of surplus plutonium. But the report ignores the numerous options that the red team discussed for addressing WIPP capacity issues.

For instance, waste volume is currently calculated based on the volume of a waste drum, not the volume of waste within the drum. This might make sense when the drum is packed solid with various transuranic wastes, but not when the actual waste only takes up a very small fraction of the drum volume, as is the case with downblended plutonium. If the actual waste volume and not the drum volume were credited, then the amount of downblended plutonium that could be emplaced in WIPP would increase by a factor of 50 or so. This means the projected available capacityfor waste at WIPP of around 19,600 cubic meters could accommodate over 2000 metric tons of downblended plutonium–much greater than the current excess plutonium stockpile of less than 50 metric tons. (This option would still require the excavation of additional repository waste drifts, however, which would require consent by the state of New Mexico.)

What about Russia?

The other issue raised by High Bridge as a major obstacle is whether Russia will accept a U.S. approach that would involve geologic disposal of the entire excess weapons-grade plutonium stockpile, given that Russia reportedly rejected such an approach back in 2000 when the initial U.S.-Russian agreement was being negotiated. (Russia did not object to the U.S. disposing of a fraction of the excess plutonium by immobilizing it with high-level waste.) Russia expressed concern that by directly disposing of weapons-grade plutonium rather than irradiating it in the form of MOX fuel in a nuclear reactor, the isotopic content (e.g. the relative quantities of plutonium isotopes Pu-239, Pu-240, Pu-238 and so on) would not be changed to “reactor-grade” and therefore the U.S. could quickly dig the plutonium up and return it to use in nuclear weapons.

First, it is important to realize that the Russians’ position was political posturing without a technical basis. DOE had previously made public a statement (confirming the views of many independent experts) that the U.S. and other advanced nuclear weapon states were capable of using reactor-grade plutonium to make nuclear weapons without any reduction in reliableyield. Changing the plutonium isotopics might pose a minor inconvenience but would not render the plutonium unusable in weapons. Russia would be far better off by supporting an option that would downblend and bury weapons-grade plutonium in WIPP on an expedited timetable rather than waiting (perhaps forever) for the MOX option to be implemented.

However, if the Russians do ultimately object to the WIPP option because it doesn’t change the plutonium isotopics, there is a way out. In a little-noticed appendix to the red team report, a proposal is outlined in which 3-9 metric tons (MT) of reactor-grade plutonium from the United Kingdom could be shipped to the U.S. and blended with U.S. weapons-grade plutonium to increase the Pu-240/Pu-239 ratio to above 0.1, the threshold defining weapons-grade plutonium in the PMDA. Although this would increase the cost of the WIPP option, it would still be far cheaper than MOX. And there would be plenty of room in WIPP to accommodate the additional plutonium if, for instance, the method for calculating waste volume discussed above were adopted.

In fact, before the red team report came out in August, UCS was in Japan putting forth a similar proposal that would use Japanese reactor-grade plutonium instead of British plutonium. Japan also has a surplus plutonium problem, with 11 MT in Japan and nearly 37 MT held by the U.K. and France. The U.S. could even purchase 10-20 MT of Japanese plutonium for its equivalent value as reactor fuel (around $160-300 million) and still save tens of billions of dollars compared to the MOX option. This approach would kill two birds with one stone by helping to deal with Japan’s own plutonium surplus and rendering moot any Russian objection to disposal of weapons-grade plutonium in WIPP.

Bottom line

In summary, there are obstacles to successful implementation of the WIPP approach, but they pale in comparison to the problems that would be experienced should the U.S. decide to press forward with MOX.

Congress needs to give DOE the space to develop a solution that will allow safe and secure disposal of excess plutonium without busting the budget.