Environmentalists went to court yesterday to keep White House inflation fighters from softening new federal strip-mining regulations.

The suit in U.S. District Court here is the first legal challenge to a series of Carter administration efforts to prevent "unnecessary" or "inflationary" new costs in federal regulations.

It raises a major constitutional question as well: how much power presidential advisers can exert behind the scenes in influencing regulations that Congress has directed agencies to write.

President Carter last fall directed his economic aides to monitor the inflationary impact of proposed federal regulations in a number of areas. Business groups have complained for years about "unnecessary" costs created by federal regulations.

The suit brought yesterday by three environmental organizations asked for a court order barring Interior Secretary Cecil D. Andrus from considering any comments submitted to him on strip mining after the hearing record was closed on Nov. 27.

Interior Department officials and representatives of the Council of Economic Advisers -- an arm of the White House -- last week and again this week discussed reservations the CEA has about portions of the regulations that are due to be published in final form in mid-February.

An interior spokesman, although declining to provide details, insisted that the talks had produced no changes in the proposed regulations. The talks were described as "beneficial and interesting."

The Natural Resources Defense Council, the National Wildlife Federation and the Council of Southern Mountains charge that White House intervention after Nov. 27 violated the federal Administrative Procedures Act and Interior Department rules.

Andrus and Charles L. Schultze, CEA chairman, and Lyle E. Gramley and William Nordhaus, CEA members, were named defendants in the suit.

The plaintiffs asked for a court order prohibiting any further meetings between Interior and the CEA and directing Andrus to disregard CEA's objections to portions of the pending strip mine regulations.

"The public interest lies in open and fair rule-making proceedings, in which all interested parties, including industry, citizen groups, state governments and sister federal agencies can make their views and interest known to the secretary," the suit said.

But, the suit charged, by allowing CEA to present informally new and critical comments on the regulations being drawn up by the Office of Surface Mining, the process had been "tainted."

In defending its closed-door meetings with CEA staffers, Interior said last week that procedures had not been violated because CEA's file memos and comments were made available for public review and comment.

The documents showed that CEA had sought and received extensive adverse comment about the proposed regulations from coal industry executives and the Department of Energy, which held that the new rules would cause major additional operating costs.

White House intervention in the regulatory process in other areas in recent months had raised questions similar to those in yesterday's stripmining suit.

The administration has challenged regulations involving cotton-dust standards to protect textile workers and transportation access for the handicapped.

Earlier this week, Schultze, chief inflation fighter Alfred E. Kahn and other White House aides met with the Environmental Protection Agency to duscuss the cost impact of pending smong-control regulations after the public comment period had closed.

Richard Ayres of NRDC, commenting on that meeting and the strip-mining controversy, said, "This is the reemergence of the imperial presidency... They are saying they can meet in secret because they represent the president. It amounts to saying the president can ignore the rules set by the Administrative Procedures Act."