The Environmental Defense Fund a private group, has accused the head of the federal Environmental Protection Agency of caving in to pressure form the White House to make all environmental sanctions on business "cost-effective."

Fund attorney Robert Rauch said yesterday that he is "extremely disappointed with [EPA administrator Douglas] Costle's performance. He is too timid, and not a fighter. The job requires a fighter."

Costle replied, "It's the EDF's job to be a very aggressive advocate on the environmental side, and it's my job to balance all of the public's interests. The job has to be done in the context of the simple fact that the congress and this administration are committed to solving out environmental problems. Obviously, I share that commitment."

The dispute arose after EDF obtained a copy of a letter from Costle to chief White House inflation fighter Robert Strauss.

Costle's letter was a response to Strauss comments that environmental regulations were too costly and would be one of the top three priority targets in the administration's fight against inflation.

Although expressing concern that "your well-intentioned comments may be widely misunderstood as an indication of reversal of the president's strong support for environmental protection," Costle said he agreed that there should be stronger cost control in environmental regulation.

"We are reviewing the marginal costs of pollutant removal for all future regulatory proposals to be sure that we adopt the least costly approaches to clean-up that are statutorially allowed," Costle wrote.

But in the end, it was Costle who had to worry about how his comments were interpreted.

After seeing a copy of the Costle letter, EDF attorney Rauch wrote to the EPA administrator to "strongly protest" his remarks and "certain actions you have proposed to Robert Strauss."

In an interview yesterday, Rauch said that Costle was giving in to pressure from Strauss to demonstrate that "benefits outweigh the costs of any actions."

"If one of Costle's economists tells him that it is going to cost $2 million to control a certain source of asbestos, and one of his scientists tells him that he will save 200 lives by doing it, how is hegoing to decide?" Rauch asked. "How much is each one of those lives worth?"

And, Rauch added, "How do you value being able to swim in the Potomac or the Hudson rivers?"

Reached by telephone, Costle denied making any environmental concessions to Strauss, and said he was only trying to be more efficient.

"My own opinion is that the benefits of what we are doing far exceed the costs that have been imposed to get there," Costle said. "But if I can get a pound of pollution out for 50 cents instead of a dollar, I'll do it."

Costle said that if "you get to the point where you are removing 95 percent of the pollution atercent, you have to ask yourself if it's worth it."

"If it's a real health risk," Costle added quickly, "you obviously are willing to pay whatever it costs. But that decision is tougher in the area of aesthetics, and you have to do a marginal cost analysis."