A House subcommittee chairman yesterday accused the Environmental Protection Agency of attempting to manipulate scientific data to cut the cost of cleaning up hazardous waste sites while increasing the public's exposure to cancer-causing chemicals.

The attack on the EPA's cancer policy, one of several new allegations that surfaced yesterday, came as White House officials pressed their search for a new EPA administrator. President Reagan, after soliciting advice from five EPA career managers at a White House luncheon Wednesday, said he hoped to find a qualified candidate soon and to put the recent controversy behind him.

It was also learned yesterday that EPA Assistant Administrator John A. Todhunter, whose office awarded a noncompetitive contract to a former employer, received twice as much money from the firm as he originally reported, and that two of the payments were made while Todhunter was working at the EPA. Todhunter said this was simply a reporting error.

And in Alabama, state officials sued the EPA on charges that the agency agreed illegally to issue a permit to allow the nation's largest waste disposal firm to truck polychlorinated biphenyls (PCBs) and other hazardous waste into the Mobile area.

At yesterday's hearing of an Energy and Commerce subcommittee, Chairman James J. Florio (D-N.J.) said, "The EPA has engaged in a deliberate attempt to rig the scientific information in an attempt to redefine one of the nation's most serious environmental problems out of existence."

Florio complained that EPA has given a "new evaluation" to highly toxic trichloroethylene, which is seeping out of Price's Pit, an abandoned New Jersey landfill, and threatening to contaminate the supply of drinking water for Atlantic City, less than a mile away.

"This new method EPA used . . . increased the acceptable level of exposure 172 times," Florio said. An internal memo suggesting the change, sent to Acting EPA Administrator John W. Hernandez Jr. last fall, said it could limit the scope of cleanup efforts at the site.

Asked about the change, Hernandez said, "I'm a total blank . . . I don't know what method was used at Price's landfill." Other EPA officials said the agency had taken emergency steps to monitor the contamination.

Ellen K. Silbergeld, a scientist with the Environmental Defense Fund, accused the EPA of "meddling with science" by "omission of data" from certain reports. "The clear intent of this revisionism is to justify a deregulation of exposure to carcinogens," she said.

White House science adviser George A. Keyworth II said the administration is developing new guidelines for regulating potential carcinogens and has dismantled an earlier cancer policy committee that included several outside scientists.

Keyworth said the nation "must devise better ways of responding aggressively to the truly serious threats . . . "

Frederica P. Perera of the Natural Resources Defense Council said that the EPA recently has allowed the sale of the pesticides permethrin and benomyl, despite estimates that they pose significant lifetime cancer risks.

Perera said a policy developed by Todhunter allows sale of pesticides that pose cancer risks 100 times greater than allowed during the Carter administration.

On another issue, EPA inspector general Charles Dempsey is investigating Todhunter's role in a $40,000 award by his office to Todhunter's former employer, Andrulis Research Corp. of Bethesda.

The EPA's general counsel, Robert M. Perry, said the award would be proper provided Todhunter was not personally involved, but a spokesman said that Todhunter never signed a formal letter of recusal, or disqualification. Instead, the spokesman said, Todhunter orally told his staff he would not participate in matters involving Andrulis.

Todhunter originally reported on his federal financial disclosure statement that Andrulis had paid him $5,736 before he joined the EPA in July, 1981. But Todhunter filled out the form for the wrong time period, and has since amended the statement to show $9,421 in payments from Andrulis.

"It was just a mistake," the spokesman said.

In addition, the Associated Press reported that Todhunter received two of the payments, totaling $1,600, after he joined the EPA. The agency spokesman said that Todhunter did not report one of these payments, which, he said, was deferred income for previous work, and is checking whether he should declare it now.

A Todhunter aide, John Ritch, said that Todhunter originally suggested a contract be awarded for unspecified research tasks. Ritch said he made the award in September as a minority "set-aside" to save time, although Andrulis did not receive its first $5,000 order until December.

Todhunter and company treasurer Peter Andrulis said they have not discussed the contract when they have met on social occasions. "We have stayed away from Todhunter, except socially," Andrulis said.

Meanwhile, in Mobile, Ala., state attorney general Charles Graddick said he has "substantial evidence" that EPA officials illegally agreed to issue a permit for a hazardous waste facility near Mobile that would be run by Chemical Waste Management Inc.

Graddick, who filed a lawsuit Wednesday to block the permit, said that Denver attorney James W. Sanderson, a former part-time EPA adviser who represents the firm, "cut a deal" to get the agency's approval of the facility even before the firm had applied for a federal permit.

A spokesman for Chemical Waste Management called the charge "absurd" and the lawsuit "totally inappropriate."

The site is on a so-called 100-year flood plain, although federal regulations forbid PCBs from being stored in such areas. Graddick released an Oct. 4, 1982 memo, in which three EPA officials suggested the site might be approved anyway.

The memo, signed by Todhunter, general counsel Perry and former hazardous waste chief Rita M. Lavelle, told EPA's regional office it could "exercise enforcement discretion" to approve the site if the firm could show that it would be "impractical" to store the waste elsewhere and that it would take adequate precautions against possible flooding.