Five congressional subcommittees are poring through thousands of pages of newly released documents, the president's counsel is gathering information and a Justice Department spokesman says his agency is "out there investigating, looking under barrels."

The complex and wide-ranging investigation of the Environmental Protection Agency shows no sign of flagging despite the departure of its most visible target, former administrator Anne M. Burford.

In a defiant attack Friday, President Reagan accused his critics of looking for political gain, not environmental protection. "I don't think they were concerned about any possible wrongdoing . . . . I think this administration and its policies were the target," he said.

But the question for the investigators is whether, in pursuit of those policies, any trangressions were committed at an agency so complex and diverse that more than 30 congressional committees and subcommittees have jurisdiction over some part of it.

Five of those panels are probing allegations about the EPA, while others are considering legislation to correct what they see as misdirected policy, whether it involves wrongdoing or not. For example, a bill recently introduced by a senator who has had no part in current investigations would require the agency to resume biological testing of pesticides suspended by the Reagan administration.

Justice and FBI investigators are gathering information at the agency, and presidential counsel Fred Fielding is conducting an "internal review" of contacts between White House and EPA officials.

Neither Justice nor FBI officials would comment on the nature of their investigations, but EPA sources said the investigators are questioning employes on use of shredders and destruction of computer records in the offices of the solid waste regulatory and "Superfund" programs. Superfund, the $1.6 billion program to clean up hazardous waste sites, is at the root of many of the allegations against the EPA.

EPA employes said the FBI inquiry also involves allegations that an "election track" system was used to grant or withhold Superfund money and that enforcement and negotiation documents on some sites were communicated to the White House.

Former EPA hazardous waste chief Rita M. Lavelle, fired by Reagan Feb. 7, has testified under oath that White House counselor Edwin Meese III or someone acting in his behalf asked her for status reports on some sites. Meese and Cabinet secretary Craig Fuller, who Lavelle described as "most likely" to have called for Meese, have denied her statements.

Fielding's review, which started about Feb. 15 but was not made public until Feb. 25, also covers the so-called "issue alerts"--on upcoming agency decisions and their political ramifications--that EPA officials sent to the White House from April to September last year.

A White House official said Fielding's review is not complete.

The House investigators, and their subjects, are:

An Energy and Commerce subcommittee, chaired by Rep. John D. Dingell (D-Mich.), is sifting four boxes of subpoenaed documents the White House agreed to turn over last week after the subcommittee agreed to protect sensitive ones. Other subcommittees expect similar access to the documents.

Dingell's subcommittee is focusing on allegations of political manipulation at five hazardous waste sites, including Stringfellow Acid Pits in California. Several EPA employes have said Burford held up a grant to Stringfellow for political reasons. Dingell also plans to interview 35 current and former EPA employes to find out if the White House was involved in decisions on cleanup grants for those sites.

A Public Works subcommittee, chaired by Rep. Elliott H. Levitas (D-Ga.), is examining conflict-of-interest allegations against Lavelle. Levitas is trying to find out when Lavelle learned that her former employer, Aerojet-General Corp., dumped wastes at Stringfellow and whether she participated in agency meetings on the site after recusing herself in June.

A Government Operations subcommittee, chaired by Rep. Mike Synar (D-Okla.), is looking into conflict-of-interest allegations involving James W. Sanderson, a Denver attorney who represented clients while a paid adviser to Burford.

Synar also is investigating whether John A. Todhunter, in charge of toxic substances and pesticides at the EPA, was unduly influenced by frequent meetings and meals with chemical industry officials before making regulatory decisions on chemical products. Synar was told last week that Todhunter has destroyed his appointment calendars and telephone logs for last year.

Another focus of Synar's subcommittee is EPA's $2.4 million settlement on the Chem-Dyne site in Hamilton, Ohio. EPA general counsel Robert M. Perry told a House hearing last week the agency may have lost two boxes of subpoenaed Chem-Dyne documents.

A Science and Technology subcommittee, chaired by Rep. James H. Scheuer (D-N.Y.), is interviewing EPA employes to determine who knew about so-called agency "hit lists" of liberal scientists, some of whom were later removed from EPA advisory boards. Scheuer also plans to call former inspector general Matthew N. Novick to explore whether he was fired because he released an audit critical of the cleanup program.

A second Energy and Commerce subcommittee, chaired by Rep. James J. Florio (D-N.J.), is focusing on 15 hazardous waste sites in New Jersey, including a site where Lavelle announced a cleanup grant with Florio's Republican opponent five days before the 1982 election. No money has been spent on that or other sites in the state.

The contempt-of-Congress citation against Burford is in limbo, as is Reagan's assertion of executive privilege over the documents. Levitas, whose subcommittee brought the contempt case, said he will ask the House to remove its citation when he finishes reviewing documents received under an earlier and more restrictive compromise with the White House.

In a more comprehensive agreement last week with Dingell, the White House did not waive its claim of executive privilege over the documents. Dingell's panel, in return, agreed not to claim that executive privilege ever applied to the documents. The agreement did not require either side to admit defeat.