A year after a massive series of explosions leveled a rocket fuel oxidizer plant in this industrial town, jittery residents still call the fire department at the first sign of smoke from the factory row where the plant once stood.

The plant no longer exists, but the psychological aftershocks still linger from the afternoon of May 4, 1988, when a small fire got out of hand at the Pacific Engineering Co. ammonium perchlorate facility and touched off thunderous blasts that blew cars off a highway a half-mile away and sent factory workers fleeing for their lives.Two people were killed and more than 300 injured in the explosions, which also destroyed an adjacent marshmallow factory and caused some $74 million in damage to businesses and residences in this city of 55,000 people just 15 miles from the glittering Las Vegas Strip.

"People are still concerned that something could happen again," said Michael Harris, a Henderson city councilman. "They're afraid another one will go up."

The fear of another blast not only forced PEPCON officials to look elsewhere for a new plant site but led to a decision by the operators of a second ammonium perchlorate plant - the only other plant of its type in the country - to also move their facility in the near future.

"We all have to recognize that a mile away we have people living," said Pat Corbett, manager of the Kerr-McGee Corp. ammonium perchlorate plant only a mile away from the devastated PEPCON plant.

While Henderson and Clark County officials quickly scuttled any thoughts PEPCON may have had of rebuilding on its original site, Cedar City, Utah, wooed the new plant to an unpopulated site about 15 miles outside the city.