The chairman of the Nuclear Regulatory Commission said yesterday he has made himself head of the agency's emergency response team and intends shortly to assume day-to-day direction of NRC operations.

Joseph M. Hendrie thus will take over leadership on the five-member commission assuming the other commissioners go along with his action.

The move, announced in an interview, is an apparent attempt to meet the key criticism of the NRC by the president's commission that investigated the accident last March at Three Mile Island. The commission concluded that the five-member panel was unable to run things effectively and ought to be replaced with a single administrator.

Hendrie and three other commissioners have defended the panel setup in memos to the White House, where President Carter is preparing a major policy statement on the future of the NRC and of nuclear power in general. White House sources said the statement could come as early next week.

Hendrie said a "one-sentence change" in the Energy Reorganization Act of 1974 that set up the NRC would be needed to legalize his control of the emergency response team, but that no new authority was necessary for him to become principal executive officer.

"We (commission members) just need to agree that the collegial body will deal with rulemaking, adjudication, major policy decisions, overall agency and planning guidelines, the budget . . . and any matter the majority of the commission wants to take up," Hendrie said.

"The chairman . . . then runs the agency, carries out the decisions of the group, and takes care of all other matters of agency business," he continued.

While insignificant on paper, Hendrie said, the change would "clear away some of the problems" of responsibility for daily operations that have paralyzed the agency in the past. It also would involve strengthening the post of executive director of operations, from its currently vague mediating role into a sort of deputy general director.

"I told them in the White House that the problems of the agency are curable in this form," Hendrie said.

Critics of the NRC have recommended, in memos forwarded to the White House in the past two weeks, that Carter replace either Hendrie or all five commissioners as a signal of his concern for nuclear safety. That would be easier than seeking to reorganize the commission along single-administrator lines, which would take congressional action. It is thought that sentiment in Congress opposes this approach.

Hendrie said the other four NRC commissioners would learn of his action by reading about it in The Washington Post, although there had been "intermittent" discussion of the subject.

"Events move at a pace that suggest delicacies of timing may not be available," he said.

Hendrie said he had placed himself in charge of NRC's emergency response team on an interim basis until the full commission can formalize the crisis reaction structure. The agency was roundly criticized for holding lengthy discussions during the accident at the Three Mile Island nuclear power plant in Pennsylvania, when someone should have been making decisions.

"I got tired of the indistinctness of things," Hendrie said, "so I called up the principal staff officers one day and said, 'Here's what we're going to do.'" In the event of an emergency, he said, he would assign various commissioners to take care of communicating with key government authorities and agencies, but would oversee the actual reactor emergency response himself.

Hendrie is the only commissioner with extensive technical knowledge of nuclear reactors. To further prepare himself for his new role, he said, he spent a week in August working on the Westinghouse Corp.'s reactor control room simulator outside Chattanooga, Tenn., and will do the same next week on the Combustion Engineering Corp. simulator in Connecticut.

"If I'm still around," Hendrie added, similar stints will follow at the training centers of the two other reactor suppliers, Babcock & Wilcox Co. and General Electric Corp.

The new legal authority required would allow Hendrie to order public utilities to take action directly, rather than requiring those orders to come from NRC's staff, he said.

Hendrie also announced that the agency's "semifinal" list of changes utilities must make in the wake of Three Mile Island will be issued between late December and early January. This will put a more definite time limit on the freeze in new reactor licensing that the nuclear industry says is costing it millions of dollars a day. CAPTION: Picture, JOSEPH M. HENDRIE . . . takes charge of emergency team