When the Obama administration came into power, one of its first actions was to end work on the Yucca Mountain nuclear waste repository in Nevada. In so doing, it delivered a shuddering blow to the U.S. nuclear industry, trashing the project when it was nearly ready to open. The cost to taxpayers was about $15 billion.

Now the administration is going through the motions to suspend another costly nuclear waste investment when it is about 67 percent complete. Money expended: $4.5 billion. Shutdown cost: $1 billion.

The object of its latest volte face is the Mixed Oxide Fuel Fabrication Facility (MFFF) on the Department of Energy’s Savannah River site in South Carolina. Work started on the facility in 2007, with a 2016 startup envisaged.

But unlike Yucca Mountain, few people outside of the nuclear industry know about the genesis and purpose of the MFFF project.

The project was initiated as a result of a 2000 agreement with the Russians, later amended, in which both countries agreed to dispose of no less than 34 metric tons of excess weapons-grade plutonium — the transuranic element that is the key component of a modern nuclear weapon, and remains radioactive essentially forever.

The DOE’s plan was for the facility to mix the plutonium with uranium to create a fuel for civil nuclear reactors to produce electricity. This recycling technology, developed in the United States originally, has been used in France since 1995.

The DOE has not yet taken a wrecking ball to the MFFF, but it is taking the first steps toward demolition. On June 25, the DOE issued a press release that the industry read as a precursor to a death warrant. The department announced that it was creating a “Red Team,” headed by Thom Mason, director of the Oak Ridge National Laboratory in Oak Ridge, Tenn., to review “plutonium disposition options and make recommendations.”

The DOE statement said the team would “assess the MOX [mixed oxide] fuel approach, the downblending and disposal approach, and any other approaches the team deems feasible and cost effective.”

Industry sources say the choice is between the MOX approach and so-called downblending. In that application, the plutonium is not burned up but is spiked and mixed with a modifier that makes it unusable in weapons. Then it would be disposed either in the Waste Isolation Pilot Plant in Carlsbad, N.M., or in a new repository, if one is commissioned.

The American Association for the Advancement of Science has been pushing the downblending option. But it is using numbers that many believe to be extremely speculative. They come from a private consulting firm hired by the DOE, Aerospace Corporation.

The first number is that the life-cycle cost of the MFFF would be $30 billion, while the life-cycle cost for downblending would be only $9 billion. These numbers are contested by the contractor building the facility, a joint venture between the construction firm Chicago Bridge & Iron Company and the French nuclear technology giant Areva. They point out that plutonium has never been downblended and that the WIPP in New Mexico has had its own problems. On Feb. 5, 2014, the plant closed after a salt truck caught fire; there was an unrelated radiological release nine days later. The plant is still closed.

It is believed that Secretary of Energy Ernest Moniz favors the MFFF approach as a permanent and scientifically attractive solution, rather than burying the plutonium in New Mexico or elsewhere. However, he may be overruled by the White House and the military chiefs, who know that they are going to have to raise money on a huge scale for nuclear weapons modernization, in light of the deteriorated relationship with Russia and China’s continuing military buildup.

If the MFFF is canceled, it will join a long list of nuclear projects that the government has ordered up and canceled later, often with a huge waste of public money. Another negative is the wastage of engineering talent. Families move to sites, buy houses and send their children to local schools. Then come the pink slips and years of demanding engineering effort are nixed by policy, politics and general incoherence in Washington.