Regional Report : SOUTH BAY : Chemical Reaction : Discovery of DDT in the back yards of two local homes has rekindled concern and fear.

At first, federal officials spoke cautiously about the white chunks unearthed in a South Bay back yard. This mysterious material, they said, could be something as harmless as construction debris.

But just to make sure, they shipped a few clumps to a laboratory for testing. And on the May morning after the results came back, the white chunks were suddenly a hot news story.

Television vans jammed the alley leading to the excavation site. Reporters took turns holding up a vial of the material as cameras zoomed in.

It was a startling find: DDT had been dug from the yard of an unsuspecting couple on West 204th Street in the Harbor Gateway area of Los Angeles. No one--not the residents, not their neighbors, not even the experts at the U.S. Environmental Protection Agency--could say where it came from.

“It’s scary. Stuff like this should not be happening. This is the 20th Century,” said Robin Hatch, 30, a mother of two who lives only three doors from where the DDT was found.

Chunks of DDT as big as bowling balls simply are not supposed to be buried in yards where one resident grew tomatoes and another held family barbecues. In a society that has grown ever more wary of pesticides--even to the point of diligently scrubbing its organic vegetables--the back-yard discovery on West 204th Street seems like an American nightmare.

EPA officials say they have no evidence that the chunks came from a DDT factory once located nearby. Yet the drama is a disconcerting reminder that DDT’s legacy looms large in the South Bay.

For years, federal officials and consultants have been quietly measuring the DDT content of neighborhood soil, attic dust, ground water, storm drains and even crabs and fish.

Their mission: to analyze the effects of the DDT manufacturing plant operated by Montrose Chemical Corp. from 1947 to 1982 on Normandie Avenue, just east of Torrance in Harbor Gateway.

The task resembles some long but engrossing detective novel, with numerous plot twists and many chapters still unwritten. It illustrates the Gargantuan job that government agencies, companies and residents confront as they try to identify and clean up industrial pollution.

Montrose became one of the world’s leading DDT producers in an era when the white powder was hailed as a magic potion.

But as Americans’ enthusiasm for the pesticide cooled, Montrose’s fortunes faltered. Today, the former factory site is one of 1,200 on the federal Superfund list of the most hazardous toxic-waste sites in the United States.

Its impact has been felt far beyond the 13-acre site, now a vacant lot. Thousands of pounds of DDT are trapped in sediment inside a local sewer line, and still more pollutes water underground.

Health experts emphasize that although DDT is a suspected carcinogen and, in large doses, can affect the human nervous system, most deposits detected around the Montrose site are too small to threaten human health.

Besides, there are only a few routes by which residents could be exposed to the DDT, health officials say. Contaminated soil could be eaten by children. Adults could consume home-grown produce sprinkled with tainted soil or eat DDT-laden eggs laid by back-yard chickens. People could ingest attic dust, which experts say is unlikely. Or they could eat DDT-contaminated fish, which is one reason the state recommends against eating white croaker caught at places such as White’s Point and Los Angeles Harbor.

Government experts say they have no evidence that such exposure has caused health problems in the area. Still, some residents wonder if the pesticide could be the source of the rashes, nausea, dizziness and aching joints that they say are prevalent in the West 204th Street neighborhood.

The outpouring of public concern in recent weeks has lent new urgency to the ongoing federal studies of how DDT affected the South Bay environment.

Montrose’s neighbors say they just want the government to hurry in its cleanup efforts.

“It’s not just hurting human beings. It’s hurting our planet,” Hatch said. “I want them to have whoever is responsible clean it up.”

The goal of the 14-year-old federal Superfund program is supposed to be exactly that: to pinpoint which companies polluted a site and require them to investigate and, as much as possible, finance the cleanup.

At Montrose, the scope of that project is enormous.

To date, Montrose and its insurance companies have spent at least $17 million for studies and initial remediation, and that’s only the beginning. A Montrose study estimates that cleanup costs for ground water alone could range from $30 million to $359 million. And although the Montrose site was first proposed as a Superfund candidate in 1984, an overall cleanup plan has yet to begin or even be announced.

Montrose says it broke no laws and notes that industrial practices changed over the past several decades. Throughout, the firm did its best to operate within industry norms and follow legal requirements, said attorney Karl S. Lytz of Latham & Watkins, a law firm representing Montrose.

Meanwhile, despite years of costly studies and legal haggling, no one can say when the South Bay’s DDT inheritance will be cleaned up for good.

Even after DDT was banned for most uses in the United States in 1972, Montrose continued making it for export to Africa, India and elsewhere. By the late 1970s, the South Bay plant was the only American DDT plant still operating. It finally shut down in June, 1982, and the building was torn down soon after.

Yet the environmental drama was just beginning.

Investigators concluded that rainwater had carried some DDT from the plant into the storm drains. Montrose installed an asphalt cap over much of the property, and testing continued.

The site officially attained Superfund status in 1989. By then, monitoring wells had detected ground water tainted with monochlorobenzene, a chemical used in DDT manufacturing that can cause liver and kidney damage.

The testing went on, unnoticed by many residents living nearby.

Then the trouble started on West 204th Street, and DDT again became a household word in the South Bay.

It was almost by happenstance that DDT was spotted in the back-yard soil.

The EPA was screening soil from 14 yards along West 204th Street to make sure it was not tainted by chemicals from the proposed Del Amo Superfund site to the north, where a synthetic rubber factory once operated.

With Montrose in mind, an agency official decided to add a test for DDT. When the tests came back last winter, Del Amo chemicals were barely detectable--but DDT showed up in samples from two back yards on the street’s north side. More tests, taken beneath the surface in the two yards, found the pesticide at 45 times the level considered safe.

Frightened residents formed a committee and fought successfully to have 25 families temporarily moved to hotels while federal crews removed toxic soil and took it to a hazardous-waste landfill in Nevada.

Cleanup was supposed to take only two weeks, but a glitch developed May 6 when workers uncovered the first of the DDT chunks. In response, EPA officials agreed three weeks ago to keep residents in temporary housing for up to six months during an investigation.

The DDT deposits appear to be scattered in fill soil that goes as deep as seven feet in one back yard. Investigators now hope to trace where the fill came from--and determine if it extends under homes to the east of the two excavated yards.

That probe, which could last through the summer, will help decide how much cleanup is needed and if residents should be permanently relocated. That would be an unusual step--taken only once before in the EPA’s four-state Western region--but one that the agency has promised to study.

“We don’t necessarily think there’s an acute health risk out there,” said Nancy Lindsay, chief of the Superfund enforcement branch for the EPA regional office in San Francisco. Although residents can choose to return to West 204th Street during the investigation, gardening or even allowing children to play in their own back yards is not advised.

Nearly four weeks after the discovery of the first DDT chunks, the EPA says it is still perplexed about how they got there.

Montrose’s attorney says he is not aware that the DDT came from Montrose.

“We have no idea of where the material came from,” attorney Lytz said.

Because of the uncertainty, the federal government is not charging Montrose for the back-yard cleanup. The cost to date: more than $500,000.

For many neighbors, an underground soup of monochlorobenzene and talk of 60-year timelines to clean it up are simply too colossal to dwell upon. Much more immediate--and more alarming--are the white chunks of DDT. For many, that simple image has poisoned the sense of security that once characterized their neighborhood. Now they worry less about cleanup schemes than about how to avoid returning to West 204th Street.

Dunia Ponce feels like a fool for having ever bought her two-bedroom house there.

“I worked very hard to buy my American dream,” said Ponce, 33, a registered nurse. “I know it’s not a mansion, a palace. But it’s everything to me.”