MIDDLETOWN, Pa., April 1, 1979

After five days of confusion and mounting controversy over who is making the potentially life-death decisions at the Three Mile Island atomic power plant, the U.S. Nuclear Regulatory Commission asserted today that from here on out it expects to have the final words.

Dr. Harold Denton, chief of reactor operations for the NRC, said his agency now has an "unequivocal understanding" with the Metropolitan Edison Co., the owner of the nuclear plant, that the NRC must be informed and concur "in advance of all actions that change either the rate of release" of radioactive gases or the "way of cooling" the reactor vessel.

Denton made the statement in the face of charges that Metropolitan Edison is continuing to vent radioactive steam into the atmosphere-and Friday discharged 400,000 gallons of slightly radioactive waste into the Susquehanna River without NRC approval.

President Carter, after touring the Three Mile Island plant today, noted that "within the next few days, important decisions will be made on how to bring the reactor down to a cold stable state."

If these decisions do not work, they theoretically could lead to a meltdown of the uranium fuel into a molten radioactive mass, posing an unpredictable threat to the 630,000 people who live within 20 miles of the plant.

The growing public concern over who makes these critical decisions was voiced today by Sen. Gary Hart (D-Colo.), chairman of the Senate subcommitte on nuclear energy.

Hart noted that while the NRC, as the agency that licenses atomic power plants, has the ultimate authority, "the utility company that wons the reactor is apparently in charge" of trying to bring the present problem under control.

"There is real doubt as to who is in charge," Hart said in a television interview.

He said he intends to sponsor legislation that would give the NRC authority to take over a nuclear reactor site during any future crisis.

"We're talking about responsibilities," Hart said. "The responsiblities of the officials of the utility are to their stockholders. Public officials have sworn an oath to protect the public. If you've got a crisis situation, I think it's the public officials that should be managing the crisis."

Walter Creitz, president of Metropolitan Edison, earlier in the day had described the decision-making process at the Three Mile Island plant since the start of the crisis as a "cooperative venture."

Creitz, whose own engineers and technical staff are being advised by a large contingent from Babcock and Wilcox, the firm that designed and built the plant, said that when it came to tackling various problems, "we've discussed different avenues with the NRC-sometimes we suggest an approach and they suggest another one."

Creitz indicated there had been no major disagreements over any decisions.

Asked who would prevail if there was a disagreement over a key question such as how to tackle the risky problem posed by the gas bubble within the reactor vessel, Creitz only shurgged.

NRC officials by late today, however, made it clear they were hardening their position on the responsibility question considerably.

"We now are making the finaal decisions," NRC spokesman R. J. Strasma declared.

Strasma said the NRC now has reactor inspectors in the control room of the Three Mile Island plant at all times. For major decisions, he said, the inspectors can be in "instantaneous contact" with top NRC officials like Denton.