Last January, the Environmental Protection Agency issued a set of rules to require special treatment for toxic chemicals such as lead before the chemicals could be dumped in municipal sewage treatment plants.

The rules were the culmination of more than four years of study that generated 400 public comments, 16 public meetings and four public hearings.

Yet, at the end of March--just three days after the rules took effect--EPA suspended them, without even notifying the interested parties.

Similarly, the Farmers Home Administration, on orders from Congress, issued a series of regulations in early January to reform rural housing assistance programs. The rules, which were published after a year of studying an extensive file of public comments, were to take effect March 20. But that same day, the Agriculture Department indefinitely suspended the final regulations --without giving the public any opportunity to comment.

Those are just two examples of how the Reagan administration is undermining the rule-making process, a coalition of 17 public interest groups charged yesterday.

In a news conference, the newly created Alliance for Justice accused the administration--and, in particular, the Office of Management and Budget--of trying to repeal federal rules without regard to due process.

Although the administration requires extensive cost-benefit studies before any new rules can be issued, it does not order similar detailed studies before it suspends or repeals rules, the group complained.

What's more, the group charged, the administration's decisions to repeal or suspend rules are often made on the basis of secret meetings and conversations OMB officials have held with scores of business lobbyists.

For example, the group's 70-page report said, the Occupational Safety and Health Administration agreed to revise part of its lead standard that requires manufacturers to provide workers exposed to airborne lead with protective respirators. The decision to revise the rule, the report said, came after OSHA officials met with representatives of 3M Corp., which manufactures a disposable respirator and had contested the original regulation in court. The revisions were then proposed without notifying any other interested party, the report said.

"This administration has gone about its work in the regulatory reform area with a sledgehammer, breaking rules that are designed to ensure citizens get a fair shake in their government," said William Taylor, chairman of the alliance.

Never before has OMB had such power over federal rule-makers, the group noted. The power stems from a presidential order, issued less than a month after President Reagan assumed office, that gives OMB the right to review all proposed and final rules before they are publicly released.

As a result of that order, the Alliance charged, OMB has rejected or delayed more than 55 proposed rules and has ordered a review of scores of existing rules without any public explanation.

The criticism comes at a time when Congress' watchdog, the General Accounting Office, is also issuing a report critical of OMB's secrecy. In testimony prepared for a congressional hearing today, GAO accuses OMB of unnecessarily refusing to give congressional auditors access to essential but nonproprietary documents so that GAO can determine how well OMB is fulfilling the requirements of the Paperwork Reduction Act, which was enacted last year.

Yet even without the necessary documents, GAO says OMB has been so preoccupied with reviewing new and existing rules that it has failed to properly implement the paper work law, which requires OMB to coordinate and supervise a government effort to reduce federal paper work and data-processing activities.

OMB officials said they could not comment on the charges because they had not read the report.

The alliance's members include environmental, women and minority rights, consumer and legal groups.