On hand for a nuclear test blast

While most agencies of the US government are cutting back, business here is booming.

For here, on 800,000 acres of cactus-studded desert north of Las Vegas, the US Department of Energy conducts underground tests of the nation's nuclear weaponry. It is one of the few programs that the defense-minded Reagan administration is accelerating.

Thus the site's weapons budget has exploded by 59 percent to a current $326 million in two years. And it has added 800 people to its payroll, swelling the ranks here to 4,400. While considerably below the 10,000 employed here in the 1960s, this represents a considerable gain from the 2,200 of the last decade.

The justification for accelerating the nation's nuclear weapons testing program, says Energy Secretary James Edwards, is that the United States ''has not tested in sufficient amounts in the last four or five years'' and testing is essential if America is to remain No. 1 in nuclear technology. The stated purpose for the continuing barrage of controlled nuclear blasting here is fourfold: to check weapons in the US stockpile to make sure they work; to determine the effects that nuclear blasts would have on military installations and equipment; to test new types of weapons' safeguards designed to prevent a nuclear bomb from exploding accidentally or if stolen; and to test new bomb designs needed to mate warheads to new delivery systems like MX or cruise missiles or to be more efficient.

What the recent increases translate into in terms of the number of tests performed here is classified. But, given the increase in funding and DOE's statement that each test costs $5 million to $12 million, it appears that the number of acknowledged bomb tests here could jump from less than 16 a year to nearly 25.

Last Thursday, on the eve of the anniversary of Hiroshima, 31 members of the press had the relatively rare opportunity to witness one of these nuclear tests.

The test blast was code-named ATRISCO, after a small town in Arizona. It was the 11th announced so far this year. Not surprisingly, the information that DOE spokesmen could give the press about this test was extremely circumspect.

Still, from a number of comments and from some circumstantial evidence, it was clear that the ATRISCO bomb was near the upper limit of those being tested here. One piece of evidence was the fact that the bomb was buried 2,100 feet below the surface. The larger the test, the farther underground it is. This was placed within 100 feet of the deepest shafts currently being used.

To witness this test blast, members of the media rendezvoused in Las Vegas at 3:30 a.m., when even the neon and glitter of this gambling town are muted. The bus reached the boxy concrete bunker of the command center with its busy-looking crown of microwave dish antennas just after dawn.

The underground auditorium where the press was shepherded was only 10 miles from ''ground zero.'' Here the visitors watched several television monitors. One came from a ground level camera aimed at the test site. A second was beamed in from a helicopter hovering overhead. A third showed the steady pen of a seismograph.

At detonation, a brilliant light flashed from the ground level view. This was a special light rigged to tell observers that the blast signal had been transmitted to the warhead. Immediately afterward the screen scrambled and went dead. But overhead the camera in the helicopter continued to record the scene. The earth appeared to craze and the area immediately over the buried bomb was suddenly covered with small puffs of dust.

At about this time the shock waves from the blast reached the control center. For five or six seconds, it felt as if the earth had turned to water and the bunker had become a ship rocking: rolling, pitching, and yawing with a surprising gentleness.

When it was over, the whole experienced seemed almost anticlimactic. It was hard to grasp that a nuclear bomb, 6 to 7 times bigger than the one that obliterated Hiroshima, had actually detonated only 10 miles away.

According to the Environmental Protection Agency crews monitoring the radiation from the explosion, the detectors spotted around the site showed nothing above normal background radiation levels.

It was not until 22 minutes later that the cavity collapsed leaving a ragged, cupped crater 1,000 feet across and 150 deep at the surface. Yucca Flat, the area where tests are currently being conducted, is dimpled with hundreds of these surface depressions. And several large drilling rigs are constantly sinking shafts for future tests.

ATRISCO was the first such test that Secretary Edwards had witnessed. He said he found the experience an exciting one. ''Being No. 1 costs us some money,'' Mr. Edwards acknowledged. ''Being No. 2 could cost us more than we are willing to pay. Most people want to keep America No. 1 because they want to maintain the freedom of our civilization,'' he asserted.

Not everyone agrees with such an assessment, however. Concern that nuclear weapons technology and the nuclear arms race has gotten totally out of control and threatens all the life on earth is behind the antinuclear movement, which has gained considerable strength in the last six months.

In fact on the day that ATRISCO was set off the proposal to freeze nuclear weaponry at current levels was debated in Congress and narrowly defeated.