MAYBE THE Bunker-Linowitz treaty on the Panama Canal will be the last. Over the years many people have watched the efforts to renegotiate the original 1903 treaty reach a diplomatic understanding and then fizzle.

One is Robert B. Anderson, the etary of the Treasury under Dwight D. Eisenhower and a confidante of Lyndon B. Johnson, who was the senior negotiator on the treaties from April 1964 to July 1973.

He accepted the task at a very tense time, four months after riots in the Canal Zone by Panamanian students left 21 Panamanians killed, four U.S. soldiers dead and hundreds injured. And President Johnson had just announced the resumption of diplomatic relations between the two countries. Twice, in 1967 and 1971, Anderson worked out new agreements that floundered.

"In 1967 the treaty was initiated by representatives of both governments," said Anderson last week, speaking from his Rockefeller Center office in New York where some of the critical meetings were held.

"The Panamanians asked that we not publicize the details before they sent the treaty to their Congress. I didn't want to do that because it would be leaked, which is what they did." He still sounds annoyed - but in a very diplomatic manner. That treaty floundered because the legislators and public figures on both side objected to some points. The 1971 drafts were rejected by the Panamanians befoe the initial stage.

"At the beginning of the negotiations the atmosphere was congenial, relaxed, a let's-get-o-with-this mood," said Anderson. "But after the coup (in 1968 when Brig. Gen. Omar Torrijos Herrara took control) the atmosphere hardened."

Anderson was known as a formal, calm, business-like negotiator who insisted on answering only to the President, but delegated many of the preparatory studies to his staff.

In 1970 a long newspaper article accused Anderson of conflicts of interest during his term as a Cabinet officer because he had received and transferred some oil rights prior to the appointment and then worked on oil issues at the Cabinet level. He described the deals as routine business matters, and is own banking investment business has continued to flourish.

When Anderson, now 67, learned of the new Panama agreements, he called Sol Linowitz, the co-negotiator, and offered help. "It was a two - minute phone call. And I told him I supported the treat, and would help in any way I could."

Shortly after the new treaty goes into effect, the Panama Canal Co. and its office of president - the holder of which also serves as governor of the Panama Canal Zone - will be footnotes in history.

Of the 17 governors to date, William E. Potter was one of the most controversial. Governor from 1956 to 1960, Potter was popular, flamboyant and denounced. He was nicknamed "Flashbulb" because his piture was in the paper all time.

In 1959 Potter called out U.S. troops to quell anti-American demonstrations that led to rioting and looting. The Protestors wanted to raise the Panamanian flag over the American-controlled zone.

"Those demonstrations were unfortunate, but I believe I handled it right. The strategy had been agreed upon by the Defense Department, State Department and the White House. I don't regret it," says Potter, now 72 and a resident of Orlando, Fla.

After his four-year term Potter worked with Robert Moses as executives vice president of the New York World's Fair and then with the Walt Disney Corp, until Potter's retirement in 1973.

"Being governor was one of the greatest experiences in the world. You oversee one of the most important waterways and 13,000 people of diverse nationalities," said Potter. "But with Moses and Disney I worked with two geniuses. ANd they degeneralized me," he said.

A civil engineer by training (the profession of most of the Canal Zone governors), Potter was a logistics planner for the invasion of Normandy during World War II, and now works as a consultant for Leisure Time Developments. "I have a very active retirement," he said briskly. He also has what he describes as "a very intense personal interest" in the new agreements on the canal, but is withholding his opinion:

"I have only gotten my news from the media, so I will not comment on generalities," he declared.