3 U.S. A-Tests Detected, Easing Verification Issue, Soviets Say

A Soviet nuclear testing expert said Friday that the Soviets have learned that the United States conducted three secret, low-yield underground nuclear tests in the past year, and this discovery shows that a total test ban is sufficiently verifiable.

The State Department, echoing the position of President Reagan, disagreed, saying that adequate verification of such tests is still an issue.

Col. Vitaly Koutashansky of the Soviet Ministry of Defense, in a news conference at the Soviet Embassy, said the United States has conducted 18 underground tests since the Soviet Union announced a unilateral moratorium on such tests Aug. 6, 1985.

He said 15 of the tests were publicly announced, but that three were low-yield and not announced. All three were apparently connected with Reagan’s Strategic Defense Initiative, known as “Star Wars,” the colonel said.

Lists Test Dates

He said that the three unannounced tests took place Aug. 15, 1985, in the autumn of 1985, and April, 1986.

A spokesman for the Energy Department confirmed that there have been 15 announced U.S. nuclear tests since Aug. 6, 1985, but he did not confirm that the low-yield unannounced tests took place.

Koutashansky said that the Soviets were able to detect the three unannounced Nevada tests “by seismic and space means” using only so-called national technical means of detection, which do not require on-site inspection.

The United States has refused to join the nuclear test ban. Among the reasons given is the fear that with present methods, a test ban could not be verified with total confidence.

The Soviets said they are prepared to accept some on-site inspections on their territory, but the exact methods and number have not been specified.

“As far as the Soviet Union is concerned, the problem of verification does not exist,” Koutashansky said.

Cites U.S. Monitoring

The Soviet expert said that the United States, which has placed about 200 seismic listening devices around the Soviet Union, has even better monitoring facilities than the Soviets, and therefore should be able to pick up any Soviet underground nuclear explosions.

State Department spokesman Charles Redman said, “The verification issue cannot be dismissed with the Soviet argument. It is much more complex than that. That’s why experts are getting together to discuss it.”

U.S. and Soviet experts met this month in Geneva to discuss the verification issue, but the talks, which are part of a series of preliminary discussions in advance of a foreign ministers’ meeting in September, ended without agreement.