EPA Plans More Test Wells Near Toxic Landfill : Pollution: The agency will trace the extent to which contaminants from the closed dump have spread in ground water.

Low levels of ground water contamination found near the Operating Industries Inc. landfill in Monterey Park have prompted the U.S. Environmental Protection Agency to dig deeper to find out how far the pollutants have spread.

Tests conducted last year on ground water collected in nine of 25 wells surrounding the 190-acre dump detected potentially dangerous chemicals in concentrations that exceeded federal standards for drinking water. But EPA officials said there is no danger that the ground water will reach supplies of drinking water.

In two weeks, engineers hired by the EPA will begin drilling a second series of up to 22 wells in residential areas of Montebello south of the dump. Tests will be conducted to determine the direction and extent of the contamination, and whether it was the result of gas and fluid seeping from hazardous materials at the landfill.

The OII dump, closed since 1984, once was considered one of the worst toxic hazards in the nation. It was placed on the national priority list for cleanup under the federal Superfund program, which makes companies and agencies liable for toxic waste even after they legally dispose of it.

So far, EPA officials said, there is no need for alarm at the findings of ground water contamination.

“It was a lot of low-level stuff,” Janet Whitlock, an EPA remedial project manager, said Wednesday during a meeting at Schurr High School that was held to discuss the drilling plans. “We expected some contamination. We do need to do more exploring to find out how much we need to worry about it. At this point we don’t need to be worried.”

The wells--each 150 to 300 feet deep--will take about five days to drill. Some will be dug in the middle of city streets, and may force traffic to be temporarily rerouted.

The monitoring of ground water contamination at the OII dump is just one aspect of an expensive plan to rid the site of cancer-causing substances that accumulated for decades as companies shipped large volumes of hazardous waste there.

Two years ago, more than 110 companies agreed to pay $65 million for part of the cleanup costs--one of the largest settlements in the EPA’s nationwide toxic cleanup program. In September, an additional 67 companies paid $9 million.

In an attempt to spread the blame, many of those companies sued the California Department of Transportation, the county and 29 cities, which the companies said were just as liable because they had also dumped toxics or hired companies to do it for them.

The suit, filed in late 1989, has been dismissed for lack of evidence against five cities--Artesia, Baldwin Park, City of Industry, Santa Fe Springs and Walnut--said Alhambra City Manager Kevin J. Murphy, who is coordinating a defense team for the cities.

The case against the remaining 24 is set for trial in February, 1992. They are Alhambra, Bell, Bell Gardens, Beverly Hills, Commerce, Compton, Cudahy, El Monte, Huntington Park, La Puente, Lynwood, Maywood, Montebello, Monterey Park, Norwalk, Paramount, Rosemead, San Gabriel, San Marino, Sierra Madre, South El Monte, South Gate, South Pasadena and Temple City.

Another problem in the cleanup is the construction of a so-called leachate plant on the northern end of the dump. The plant will collect and treat leachate, an oily, contaminated liquid that forms when water runs through waste, and is commonly referred to as garbage juice.

A coalition of companies running the cleanup program has applied for a permit to use Monterey Park’s sewers to transport the treated leachate to a Los Angeles County sewage plant. City officials, however, are studying alternatives, such as asking the EPA to build its own sewage lines for the leachate, said Chuck Bergson, Monterey Park’s assistant city engineer. The City Council will decide Dec. 9 whether to grant the permit.