The Arms-Control Challenge: How to Disarm Quickly Enough

WITH arms deal following arms deal at breakneck speed in recent months, American and Russian weapons scientists are facing a problem they never thought they would have: how to throw away tens of thousands of nuclear weapons.

Where once-secret labs on both sides labored on designs for new warheads, now they work on speeding up the process of taking old ones apart. The chief worry now is how to store the dangerous parts that will be left over, particularly plutonium and highly enriched uranium fissile material.

Dismantling all the weapons that the United States and Russia have already agreed to scrap could take a decade or more. And while the world is undoubtedly a safer place with smaller superpower nuclear arsenals, the dismantling process is not without risks. Somewhere along the disassembly line, terrorists or rogue states might find an opportunity to obtain precious fissile metal.

"This material could be recycled back into weapons," says an administration official who spoke with reporters on condition of anonymity.

In fact, one issue currently being debated within the US government is whether to call for some sort of organized verification of Russian storage and destruction of nuclear warheads and fissile material. Earlier this month a Senate panel called for such monitoring in connection with any post-START agreement cutting long-range nuclear arms.

Strictly speaking, arms pacts to date call for destruction of delivery systems such as rockets, not warheads. But as a practical matter, retired warheads will at least be withdrawn and disarmed, and usually disassembled as well.

Verification could ease concerns about the whereabouts of all bomb material that once belonged to the Soviet Union - material that is now spread among several republics besides Russia. But in the name of reciprocity it might open US military fissile-metal stockpiles and production plants to inspection, perhaps by an international agency. That is not something the Pentagon and Department of Energy (DOE) want to accept.

"If they put this stuff under safeguards and we don't, we'll be subject to lots of criticism," says the administration official. Recycling warheads

Last week, the Bush administration announced an official cutoff of production of plutonium and highly enriched uranium. This was, in essence, an attempt to get credit for moves that have been forced by circumstances.

For one thing, the nuclear-materials production complex is now shut down by environmental problems. No new nuclear warheads are currently in production, and a large potential stockpile of fissile materials in warheads is being retired.

Recycling thus appears the wave of the future for the US nuclear-weapons complex, when or if new warheads are built. According to just-declassified budget documents submitted to Congress earlier this year, DOE is building a capability to reuse fissile-weapon "pits" at its Pantex weapons plant near Amarillo, Texas.

The B61 tactical nuclear bombs delivered last year were "a conversion" from scrapped W85 Pershing II warheads, according to the documents.

So many retired weapons will flood into Pantex, the only US facility for assembly and disassembly of nuclear warheads, that officials are worried about exceeding its capacity. According to the budget documents, current pit storage facilities are "insufficient."

Pantex will be able to disassemble 1,800 warheads in fiscal 1992, and 2,000 in 1993. Yet even at this rate the average time between a warhead's "retirement" and its dismantlement will likely grow from 24 to 48 months, according to a DOE projection.

"We cannot be certain that ... stockpile dismantlement time schedules can be achieved," concludes a DOE document. Russia cannot meet timetables

Russia will probably be even more hard-pressed to withdraw and dismantle warheads in a timely manner. The Russian nuclear infrastructure is so decrepit that some officials there have asked that $400 million in already-promised US aid be used to build new fissile-material storage areas.

In Russia two main dismantlement issues are now being debated, says a US official. The first is whether the process will be controlled by the military or by atomic-energy civilians. The second is what use will be made of the precious, yet highly toxic, plutonium and highly enriched uranium.

Will warhead components in Russia simply be stored, a situation in which they could be reconverted to military use with uncomfortable ease? Will they be destroyed in some manner, such as underground detonations? Or will the highly enriched uranium be converted to fuel for use in civilian power plants?

Russia has about 500 tons of highly enriched uranium, according to US estimates, which can be made into commercial fuel by combining it with natural uranium. Total market value could be upward of $7 billion.

But, as far as reactor fuel goes, "the market is already saturated," the US official notes.

Plutonium can't be reused in civilian reactors. Although some have suggested launching it towards the sun, the US official says, "it's inevitable that for the foreseeable future it will be stored."