National Agenda : Ukraine Toys With Nuclear Second Thoughts : A growing faction says destroying the world’s third-largest arsenal would cost too much in money and security.

When Ukraine declared in July, 1990, that it would be a “nuclear-free zone,” nothing seemed more natural. The Chernobyl nuclear disaster four years earlier had been a grim lesson in the atom’s terrible power.

So when Ukraine’s Declaration of Sovereignty was passed by Parliament on that hot summer day, it was in a fit of patriotic emotion and without much talk about its “non-nuclear” provision. At the time, the oversight seemed hardly to matter.

But when an independent Ukrainian state emerged from the Soviet Union’s ruins last December, it suddenly found itself the reluctant “owner” of the world’s third-biggest nuclear arsenal. And it is only now facing up to the full, and troubling, implications.

For a time, free Ukraine signaled its abiding aversion to nuclear weapons by rushing headlong into formal pledges of disarmament--again, as during the adoption of the sovereignty act, without even the most elementary expert analysis.

But clearly, events of recent weeks have shown that those days are over. As Ukraine begins seriously confronting the economic, political and security implications of nuclear disarmament, a growing pro-nuclear faction in Parliament, the Supreme Rada, is threatening to derail ratification of the Strategic Arms Reduction Treaty (START) that was forged between the United States and the Soviet Union.

The fate of the Nuclear Non-Proliferation Treaty, under which Ukraine must eventually give up all its nuclear weapons, may also be in doubt. How the Kiev government resolves these issues seems likely to present a knotty challenge to Russia and Ukraine’s other neighbors, as well as to the Bush Administration and President-elect Bill Clinton.

The changed tone in Ukraine’s disarmament debate can be traced to the election of Leonid Kuchma as prime minister last month. A straight-talking rocket engineer who used to direct the largest missile factory in the world, the 56-year-old Kuchma contrasts sharply with President Leonid Kravchuk.

The avuncular, silver-haired president has been hinting about Ukraine’s disarmament problems for months but always with slippery ambiguity. At a news conference last week, for example, Kravchuk said that Ukraine “should have appropriate compensation” for giving up its nuclear weapons but didn’t specify.

By contrast, sophistry is not the forte of the premier. In a rare interview with The Times, Kuchma seemed forthright and in command of the technical details about his government’s nuclear policy.

He repeatedly insisted that the Kiev leadership is committed to disarmament, saying, “There should not be nuclear weapons on Ukrainian territory under any circumstances.” But, he added, Ukraine needs more support from the West to get rid of them.

One of the biggest problems is purely financial. Ukraine’s 15% share of the Soviet arsenal was quickly reduced when it handed over about 2,000 short-range battlefield nuclear weapons to Russia last spring. But it still has 176 land-based intercontinental ballistic missiles armed with more than 1,200 warheads, and the staggering price tag for neutralizing all of them will run into the billions of dollars.

To disarm, Ukraine needs to build factories to process the highly toxic liquid propellant that fuels its 130 SS-19 missiles. As for the 46 SS-24s, special hothouses must be built to prevent the solid fuel they carry from exploding while scientists figure out how to dispose of it.

“All of this costs money,” said Kuchma, though he hesitated to name precise figures at a time of runaway inflation. In any case, he said, Ukraine by itself cannot afford it.

Under START, Ukraine is also supposed to demolish the ICBM launchers and the silos where the missiles are housed. But Ukraine’s two ICBM bases near Derazhnya and Pervomaysk are planted in the midst of its agricultural heartland, and Kuchma contends that exploding the silos would threaten to transform large swaths of Ukraine’s famously fertile black earth into barren desert.

Instead, he says, Ukraine wants to negotiate “more civilized means” of demilitarizing the missile shafts.

“Ukraine wants this land for plowing, sowing and growing,” he says--and not only around the silos but in them.

One western Ukrainian agribusiness firm is already planning to supplant nuclear warheads with mushrooms by growing champignons in the abandoned shafts. Then there is the vexing problem of Ukraine’s 1,240 nuclear warheads--six per every SS-19 and 10 for each SS-24. They appear to have fallen into something of a legal loophole, as START does not address their fate at all.

And the Lisbon protocols, which the Soviet Union’s nuclear heirs--Belarus, Kazakhstan, Russia and Ukraine--signed last May to formally commit themselves to START, leave such details to be hammered out among the “nuclear republics.”

After the birth of the Commonwealth of Independent States that succeeded the Soviet Union, Ukraine agreed to give up its nuclear weapons to Russia but with the proviso that the transfer was only so that the weapons could be destroyed.

That condition has made its remaining warheads the prize in a tense campaign undertaken by Washington and Moscow to make Kiev live up to its promises.

Ukrainian leaders now retort, however, that Russia has already violated its commitments by not destroying the loads of tactical nuclear warheads that they already handed over to the Russians last spring.

When the Bush Administration made a deal recently to buy the highly enriched uranium in Russia’s warheads, that complicated matters even more in Ukraine by putting a price on disarmament.

“What did we get for the tactical nuclear weapons we gave to Russia? Nothing,” Kuchma objects.

Actually, Ukraine was not supposed to get anything, but if Russia is now going to make money by selling the fissile material from its deactivated warheads, Kuchma doesn’t see why Ukraine should give its material away.

One way of getting a cut of Moscow’s uranium profits is a deal now in the works to barter Ukraine’s strategic warheads for the nuclear reactor fuel that it now must buy from Russia.

If that doesn’t work--and Kuchma hopes that it will--Ukraine will put the fissile material from the warheads up for sale.

The only potential customer the Ukrainian premier mentioned is the United States, though the prospect of other buyers appearing makes the scheme sound like an offer Washington is not supposed to refuse.

In all, Kuchma sees an unfair tilt in Washington’s nuclear weapons policy. “They want to disarm us in exchange for a thank you, leaving Ukraine with billions in expenses . . . while Russia, where all these nuclear weapons will remain, will get billions of dollars in aid,” he charges.

The perception that Russia is getting lavish attention and foreign aid money because it will remain a nuclear power has also given ammunition to Ukraine’s growing number of nuclear hawks. Many see their fragile state threatened by renewed Russian imperialism and consider it ludicrous to give Moscow even more nuclear ammunition.

“We would be arming a potential adversary,” protests Yuri Kostenko, who led an ad-hoc parliamentary group on the START treaty before becoming minister of the environment in Kuchma’s government last month.

The new minister isn’t alone in his views. During last month’s heated debate over a draft security doctrine that implicitly identified Russia as a potential military adversary and explicitly rejected nuclear weapons, the hawks vociferously rejected complete nuclear disarmament.

The country’s 700,000-strong army may be larger than Germany’s, but it is far from the world’s best, and the full loyalty of many former Soviet units commandeered by Kiev is questionable. “We need a nuclear deterrent. We can’t guarantee our army’s fighting ability without it,” one deputy argued.

Ukraine’s nuclear doves, including the man whose opinion may finally matter most--President Kravchuk--counter that possessing The Bomb on one’s territory does not alone make one a nuclear power. In Ukraine’s case, the elite troops staffing the ICBM silos still answer to orders from Moscow.

Moreover, the Russians still hold the monopoly on uranium enrichment and warhead manufacturing in the former Soviet Union. And they also hold the launch codes for Ukraine-based missiles, although Ukraine’s advanced rocket industry is reportedly drawing up plans to give Kiev a “double key” that could block launches from its territory.

In any case, if Russia is the threat, Ukraine’s ICBMs were not designed to hit close-range targets such as Moscow. According to a Pentagon analyst, ICBM warheads could be installed on refitted short-range missiles but “that would be overkill.”

Kravchuk has also argued that going back on Ukraine’s disarmament promises would “turn the world upside down,” but some hawks simply don’t care. Volodymyr Tolubko, an ex-major general in the Soviet strategic rocket forces, declared to Parliament that Ukraine “should care less about what the world thinks of us and think more about what it can do to us.”

The proposed security doctrine was sent back by deputies for reworking, but the debate in the Supreme Rada revealed the hawks’ growing influence. They are still in the minority. But nuclear advocates have won some converts among doves who wanted to disarm but now fear that the West will abandon Ukraine the moment it gives up its weapons.

Nuclear Opinions Most people in Ukraine oppose nuclear weapons, according to recent poll, with ethnic Russians most opposed. Results from two cities: “Do you agree or disagree with the statement: ‘I think that Ukraine should have its own nuclear weapons.’ ” KIEV Agree Russians: 29% Ukrainians: 39% Disagree Russians: 66% Ukrainians: 53% SIMFEROPOL Agree Russians: 11% Ukrainians: 23% Disagree Russians: 83% Ukrainians: 65% SOURCE: “Russians as Ethnic Minority in Ukraine,” by Ian Bremmer of Stanford University.

Ukraine’s Missile Arsenal:

SS-19 (Stiletto) Number deployed: 130 Type: Silo-launched intercontinental ballistic missile Range: 6,200 miles Propulsion: Two-stage liquid booster plus post-boost vehicle Length: About 88 feet Warheads: Nuclear. Up to six. History: Deployed 1974-82.

SS-24 (Scalpel) Number deployed: 46 Type: Rail-mobile and silo-launched intercontinental ballistic missile Range: 6,200 miles Propulsion: Multi-stage solid motors plus post-boost vehicle Length: About 72 feet Warheads: Nuclear. Up to 10 re-entry vehicles. History: Tested 1982. Rail-mobile version deployed 1987; silo version later. Source: Jane’s Weapons Systems 1988-89; U.S. Defense Department