Civil defense in 1982: don't dig a shelter, just calmly leave the area

For more than a decade, it has been easy to think of civil defense in the past tense. The original US strategy for nuclear-war survival - dig shelters to house the population - was largely discarded in the 1960s and '70s as impractical. The reason: an estimated $70 billion to $120 billion price tag.

Now, with hopes for a nuclear arms reduction treaty languishing, the US is embarking on a sweeping new program of strategic rearmament. And civil-defense planning is back - or rather, back in the limelight. Government policymakers had never abandoned it.

The federal government will spend $128 million for civil defense this year. That doesn't mean a revival of the fallout-shelter mania of the 1950s, however. In 1976 and 1977, the watchword in civil defense shifted from dig-a-hole to head-for-the-hills. Or, in the federal jargon, to ''crisis relocation.'' The new goal of civil defense: to evacuate high-risk cities and strategic areas to the countryside.

The Federal Emergency Management Agency (FEMA) is charged with planning and coordinating ways to counter various possible disasters - especially nuclear attack. Since 1979, FEMA has worked quietly on evacuation plans with government officials in high-risk areas, and in the ''host'' areas where evacuees would be sent. These local emergency chiefs - in some cases merely county sheriffs - form the ''front line'' that would manage any evacuation.

Earlier this year FEMA announced its still-unfinished emergency plans for the Northwest. FEMA ranks the entire Puget Sound area, with its many defense-related industries, as the highest-risk area in the region, and among the nation's top ''hot spots.'' It could thus serve as a model for the way evacuation would proceed.

FEMA rates sites such as the Trident submarine base at Bangor, across Puget Sound from Seattle, and the McChord Air Force Base near Tacoma as the most likely targets of enemy attack. Next come key military facilities and defense industries: Tacoma's Fort Lewis, the Bremerton Naval Shipyards on Puget Sound, and Seattle's vast Boeing aircraft works. Following them on the FEMA list are urban areas with populations of 50,000 or more.

About 2.3 million people live in the Puget Sound area. Under the present plan , the idea would be to evacuate those people to nearly every other part of Washington. It is intended that about one-tenth would go to the state's southwest corner, where sea winds give some of the best likely protection against fallout in the nation. But the plan foresees most going to the eastern side of the Cascade Range where prevailing west winds dropped a heavy foretaste of fallout, in the form of volcanic ash, during Mt. St. Helens's eruptions.

FEMA's risk categories do not include several possible targets in eastern Washington areas that are scheduled to receive evacuees: the airstrip at Moses Lake; Grand Coulee Dam, the destruction of which could cripple many cities; and the nuclear-weapons manufacture center and nuclear plants (under construction) at Hanford. Irving Silver of the Northwest FEMA center confirms that Hanford and Grand Coulee are still being ''considered'' as potential targets.

Even if small host towns could provide shelter for thousands of refugees, provision of necessities remains a big ''if.'' Washington emergency services coordinator Joel Aggergaard says food wholesalers stand ready to reroute trucks to evacuation sites. But he admits water and sewerage preparations are ''not adequate.''

For sewerage, evacuees could expect ''a lot of improvisation, like GI pit systems.'' Emergency food in most existing shelters has either gone stale or been discarded.

City residents could not be evacuated on short notice. The target time of FEMA evacuation plans is 72 hours. Officials in Spokane, whose plan was developed earlier, believe that city could evacuate in 54 hours. Seattle, whose bridges are commuter bottlenecks, is a trickier challenge. The most optimistic estimate so far is 79 hours.

A nuclear attack warning would allow only 20 to 30 minutes notice. But officials expect a much longer warning: days or weeks of mounting international tensions and saber-rattling. The expected cue: a corresponding Soviet evacuation.