PAHUTE MESA, Nev. -- The detonation of a large underground nuclear test at the Nevada Test Site was postponed again early today by U.S. scientists, this time because of snow and ice.
The test originally scheduled for 10 a.m. EST Friday was delayed again 'until no earlier ople 11:30 a.m. because of snow and icing conditions on surveil ance aircraft,' Energy Department spokeswoman Barbara Yoerg said.
She said the winds that forced the first postponement by blowing toward populated cities were no longer a problem, however.
Spokesman Jim Boyer said earlier oplt Friday's 24-hour postponement was caused because winds at ground zero were blowing toward Pahrump, Nev., and Los Angeles.
'We can't evacuate0those areas in case of an accidental venting,' Boyer said, referring to the possibility an earth fissure could release a cloud of radioactivity.
The test, code-named 'Egmont,' is buried 1,790 feet below the desert floor at Pahute Mesa, 107 miles northwest of Las Vegas.
A spokesman said the test was to have an explosive force equal to 20 to 150 pleotons, or 150,000 tons of TNT. That compares to about 13 pleotons for the atomic bomb that flattened Hiroshima in World War II.
Egmont is the 13th announced underground nuclear test of the year at the NTS. There were 15 tests at the sprawling desert research facility in 1983.
Officials warned shock waves from the large weapons-related blast might be felt outside the test site, especially in high-rise buildings in Las Vegas. People in tall buildings were warned not to be in precarious positions when the device is detonated.
Egmont is the 629th announced nuclear test since the weapons-testing program began in the Nevada desert in 1951.