Soviets, U.S. monitor Nev. A-blast

MERCURY, Nev. Exactly on schedule and under ideal conditions,Soviet and U.S. technicians made history Wednesday by jointlymonitoring a nuclear explosion beneath the Nevada Test Site.

The bomb - painted red, white and blue - went off to open whatparticipants called a new chapter in nuclear arms control. SevenSoviet scientists sat side-by-side with their U.S. counterparts inthe crowded control room deep inside the classified site.

It was the first such joint effort since the Atomic Age dawned43 years ago.

"This is an auspicious start for the Joint VerificationExperiment and a critical hurdle for this process," EnergyUndersecretary Joseph F. Salgado said after watching techniciansmeasure the power of the explosive that rippled the surface of DeadHorse Flat at 10 a.m.

"As a result," Salgado said, "we are one step closer tocompletion of the verification protocols for the Threshold Test BanTreaty and the Peaceful Nuclear Explosions Treaty."

Those treaties were signed in the mid-1970s but not ratified bythe Senate because of concerns over ability to verify Sovietcompliance.

Despite optimistic predictions from both sides Wednesday aboutthe treaties, U.S. and Soviet officials remained at odds over how farthe experiment here would advance the cause of strict new test bans.

Igor M. Palenykh, head of the Soviet delegation to bilateralnuclear testing talks in Geneva, remarked through a State Departmentinterpreter that the experiment could and should lead to "furtherlimitations of nuclear tests, both the number of tests and theiryield."

"The ultimate step, of course, is the total cessation of nucleartesting," he said, recalling the Soviets' unilateral test moratoriumof the early '80s. "We plan to make every effort to achieve thisobjective."

The U.S. leader at the testing talks, C. Paul Robinson, quicklystepped in to say that his country was not nearly as keen to do awayentirely with nuclear tests.

"The United States still believes that it must rely on nucleartesting just as long as it must rely on nuclear weapons for itsdefense," he said. "But this event is proof that we are makingprogress on measures that will lead to a more stable world."

That conflict aside, the Soviet and U.S. technicians anddiplomats were generally jovial after the event, the first of twonuclear blasts planned as part of a Joint Verification Experimentdesigned to demonstrate the feasibility of several test-limitationverification technologies.

Code-named Kearsarge, it had a yield near 150 kilotons - nearly12 times larger than the World War II atomic bomb dropped Aug. 6,1945, on Hiroshima, Japan.

The second explosion is scheduled Sept. 14 at the Semipalatinsktest site in Soviet Central Asia.

Viktor N. Mikhailov, leader of the Soviet technical team,touched off a brisk round of applause in the control room 30 secondsafter the detonation, when he jubilantly punched the air to signal hehad received good news from Soviet technicians staffing recordingequipment in a nearby building.