Hale Champion has made the big time. He eats lunch most afternoons with Joseph A. Califano Jr., the Secretary of Health. Education and Welfare. Congressional committees anxiously await his testimony on welfare reform. When he emerged from a Senate Finance committee hearing on his confirmation as the Undersecretary of HEW last Wednesday morning, half a dozen reporters pounced on him in the corridor to ask questions about his testimony.

It was a far cry from Harvard, where Champion worked in Mass Hall as financial vice president, ate lunch at the Faculty Club, and got phone calls from frantic Crimson reporters at 11 p.m.

Since January 20, Champion has worked as Undersecretary in a suite of offices next to Califano's on the sixth floor of HEW's newest building in Washington.

For two months, his nomination languished in the Senate Finance Committee. On March 8, the Health subcommittee, chaired by Sen. Herman E. Talmadge (D-Ga.), held a hearing on his nomination that committee staff members said was routine.

Meanwhile, HEW's chief investigator, John J. Walsh, resigned from the department because he thought Califano was trying to slow down Walsh's investigation of Medicare fraud in California, particularly his probe of Flora Souza, president of Home Health, Inc. in San Jose.

Walsh alleged that Califano effectively put the lid on the investigation during a meeting where Champion was also present.

Because all the other participants in the meeting were already confirmed. Champion's confirmation became the focal point of the Finance Committee's investigation into Walsh's charges against Califano.

Once Talmadge, backed by the committee staff, opened the Walsh-Souza can of worms, the Republicans on the committee were eager to keep the heat on.

On Wednesday, Talmadge read a statement explaining the reasons for the delay in Champion's confirmation, but ended by saying that he should be confirmed.

Sen. Carl E. Curtis (R-Neb.) then asked that the committee not vote on Champion's nomination until after Califano appeared to answer a few questions.

Within half an hour, Califano had come up Capitol Hill and was testifying that he had not really intended to slow down Walsh's investigation.

Walsh, sitting next to him, agreed that it had all been a "misunderstanding," and that everyone should get on with the real business of ferreting out Medicare. Medicaid and welfare fraud.

The Finance Committee, a group studded with stars like Sen. Daniel P. Moynihan (D-N.Y.), Sen. Abraham Ribicoff (D-Conn.), Sen. Robert Dole (R-Kan.), Sen. John Tower (R-Tex.) and chaired by Sen. Russell Long (D-La.), then voted unanimously to send Champion's nomination to the full Senate with a recommendation to confirm him.

The Senate Majority Leader's office said yesterday that Champion's nomination is on the Executive Calendar and could come up at any time. It is expected to be approved at last without serious debate or challenges.

Harvard appears to have some powerful friends in Washington these days, with former employees like Champion and Moynihan on both sides of the hearing table.

As HEW's number-two man, Champion is supposed to manage HEW's budget, which is the federal government's largest. But his influence extends to all parts of HEW, something about which Harvard's administration cannot be unhappy.