Although the Soviet Union made worldwide headlines this week in announcing plans to destroy chemical weapons, U.S. experts say the Soviets are likely a long way from actual destruction of large stocks of weapons.

Based upon U.S. experiences at Utah's Tooele Army Depot and other chemical stockpile locations, it may take the Soviets years to move from testing and planning to large-scale destruction."Destroying chemical weapons is not something that you just say you're going to do today and start tomorrow," said Maj. Dick Bridges, a Department of the Army spokesman at the Pentagon,

Soviet Embassy spokesman Boris Malakhov in Washington, D.C., told the Deseret News he and other Soviet officials in the United States don't know when chemical weapon destruction might begin.

The United States has been testing disposal methods and equipment at Tooele Army Depot since 1979 and is only going to start destruction this fall at Johnston Island in the Pacific. Even then, the first 16 months will consist of operational testing of various agents and munitions.

Destruction of weapons stored at Tooele and seven other mainland locations will begin later.

The Soviets clearly won't be able to begin large-scale destruction of their chemical stockpiles for years, said Brad Roberts, a research fellow at Georgetown University's Center for Strategic and International Studies who specializes in chemical weapons.

But it shouldn't take them as long as it took the United States, because they can take advantage of U.S. test findings, most of which are unclassified, said Marilyn Tischbin, spokeswoman for the Army's disposal program. Last fall a Soviet delegation toured Tooele's Chemical Agent Munitions Disposal System and saw the process.

And the Soviets won't have the same congressional funding and environmental hoops to jump through that the U.S. Army has had. Although they, like the Americans, will be concerned about safety, "I don't think they're going to be holding public scoping meetings and issuing draft environmental impact statements," said Bridges.

Environmental and safety concerns were a key factor in the U.S. decision to destroy existing chemical weapons where they are stored, rather than transport them to a central site. Because of that, Tooele Army Depot will have the lion's share of the disposal job. In tons of agent, it now stores 42.3 percent of the nation's supply.

The Soviet Union made worldwide headlines with Foreign Minister Eduard Shevardnadze's announcement Sunday of plans to open a plant this year to test ways to destroy chemical weapons stocks.

At a later press conference, though, Deputy Foreign Minister Victor Karpov couldn't say how many weapons would be destroyed. He tied the "tempo" of the destruction to progress in the Geneva negotiations on an international convention to ban chemical weapons.

Karpov also said it hasn't been decided whether the weapons destroyed will be old or newer ones. But a U.S. administration official who declined to be identified told the Deseret News, "I'm sure it's their old stuff. I can't

imagine them destroying good stuff."

The United States ceased production of chemical weapons in 1969. And Congress has ordered destruction of the entire existing stockpile.

But the destruction of existing weapons will occur together with production of new binary ones, considered safer than the old unitary weapons because they store nerve agent in the form of non-toxic components that don't mix to become lethal until they're used.

New binary artillery shells went into production in December 1987. The 155mm artillery shells and one of their two chemicals will be stored at Tooele, as will the Bigeye bombs and one of their two chemicals, said Jeff Lindblad, spokesman for the Army's Chemical Research and Development Center. The Bigeyes are not yet in production.

Congress initially set 1994 as the deadline for destruction of the existing stockpile, but that was later pushed back to 1997.

The Soviets announced they had stopped their production of chemical weapons in 1987. Malakhov said any weapons destroyed will not be replaced. "We are strong opponents of binary weapons."

Despite that assertion, the U.S. official who declined to be named said Soviet plans regarding binaries remain an open question.

Roberts said reports have appeared in the open literature that the Soviets are pursuing binary technology, but he knows of no evidence that they plan to resume any chemical weapon production.

Because their military chemicals were produced at the same plants where commercial chemicals are made, however, "they could begin production this afternoon of huge quantities of chemical weapons if they wanted to," he said.

Many of the United States' old weapons were built 30 or 40 years ago, as most likely were some of the Soviet stocks. Nerve agents are highly corrosive, and some of the U.S. munitions are leaking their deadly contents.

Roberts said the U.S. plan is to replace the unitary stockpile with a binary stockpile of less than one-third its size in terms of tons of nerve agent.

That does not represent a two-thirds reduction in chemical warfare capability, however, he explained, because 75 to 90 percent of the existing stockpile is unusable. Some weapons are corroded and too dangerous for use; some agent is stored in munitions for which the delivery system has been phased out; and some agent is in bulk storage but necessary munitions are not available.

Although systematic demilitarization of the unitary stocks will begin this year at Johnston Island, tests of the best way to demilitarize the aging weapons have been going on for years.

In that process, 134.9 tons of chemical agents were neutralized or incinerated at Tooele between 1979 and 1988, said depot spokeswoman Susan Nelson.

Before that, the Army disposed of its weapons stored at Rocky Mountain Arsenal, near Denver, neutralizing or incinerating 7,181.15 tons of nerve and mustard agents, according to a 1987 Army summary.

Tischbin said the work at Tooele has consisted largely of refining the processes and equipment used at Rocky Mountain. Chemical neutralization was used for some of the nerve and mustard agents at Rocky Mountain, but officials were not satisfied with how well it worked for nerve agents and have switched to incineration, she said.

One focus of the Tooele work has been on how to remove the chemical agent from the munitions. For example, rockets initially were cut open with a rotary saw. "It worked, but we found that it heated up the saw blades and the blades didn't last very long." So a shear system "like a guillotine" will be used at Johnston, she said.

The total size of the U.S. chemical stockpile is classified, but Roberts and Matthew Meselson, a Harvard biochemistry professor specializing in chemical weapons, said widely accepted estimates put it between 30,000 and 35,000 tons of agent.

The Soviets say their stockpile consists of 50,000 tons of agent. But U.S. estimates of its size range from 30,000 to 700,000 tons, said Meselson. It's very hard to tell who's right, he said, and more than once he's seen "a shocking, rather simple-minded confusion between tons of agent and tons of munitions."

If the Soviets do have a much larger supply than the Americans, it may well take them longer to destroy it than the eight years the Army and Congress have planned for U.S. stocks, he said.

To put the stockpile estimates in perspective, it's been said that one milligram, or about one-fiftieth of a drop, of the nerve agent GB, or sarin, can kill a person. But Meselson said that kind of figure can be misleading. He said that in typical battle use, one ton of GB would probably kill about half of the people in a square mile unless they were wearing protective gear.

***** (Chart) Chemical destruction schedule

Percent of U.S. agent

Disposal Location Startup Completion tonnage

Johnston Island Sept. '89* Dec. '92 6.6**

Tooele (Utah)

Army Depot Dec. '92 May '97 42.3

Pine Bluff (Ark.)

Arsenal Jan. '94 Nov. '95 12.0

Umatilla (Ore.)

Army Depot Sept. '94 June '96 11.6

Anniston (Ala.)

Army Depot July '94 Sept. '96 7.1

Pueblo (Colo.)

Army Depot Dec. '95 Apr. '97 9.9

Newport (Ind.) Army

Ammunition Plant May '95 Sept. '96 3.9

Lexington-Bluegrass

(Ky.) Army Depot Dec. '95 Dec. '96 1.6

Aberdeen (Md.)

Proving Ground May '95 Sept. '96 5.0

*Sept. 1989-Jan. 1991 at Johnston will be operational testing.

** The percentage of agent tonnage for Johnston includes amounts stored at sites in Europe.