John F. O'Leary, 62, who served for many years as a high-ranking federal official concerned with energy and who later became head of General Public Utilities Corp., died of cancer Dec. 19 in Philadelphia.

During federal government service under four administrations, Mr. O'Leary, an economist, was at various times principally concerned with coal, natural gas and atomic energy. He also was considered knowledgeable in the areas of oil and electricity.

He was head of the Federal Energy Administration under President Carter, and after Carter created the Department of Energy, Mr. O'Leary was appointed in 1977 to become its second in command, as deputy secretary.

Mr. O'Leary resigned from the Energy Department in 1979. Later that year he joined the board of GPU in the aftermath of the accident at GPU's Three Mile Island nuclear plant.

He became chairman of GPU Nuclear Corporation in 1984 and became chairman and chief executive officer of GPU Corp. this year.

As Federal Energy Administrator, Mr. O'Leary gave strong suport to federal regulation of strip mining and told a Senate subcommitee that "the cost of reclamation is not high and we should not be misled to believe that concern for our environment and the production of energy are incompatible."

As head of the Bureau of Mines during the closing months of the Johnson administration and the beginning of the Nixon administration he was credited with vigorous efforts in behalf of miner safety and environmental protection.

At the time of his 1970 dismissal, reporters were told by sources that the ouster was connected to his strong support of mine safety laws.

After leaving the mine post and before returning as energy administrator, Mr. O' Leary, a Reno, Nev., native worked for the Mitre Corp. and as secretary of energy and minerals for New Mexico. Before becoming GPU chairman he was president of a consulting firm.

Survivors include his wife, Hazel Reid O'Leary.

MILDRED ROSA MARTINELLI,

88, an area resident since 1935 who was active in church and volunteer groups, died of leukemia Dec. 20 at Fairfax Hospital. She lived in Falls Church.

She was a member of St. James Catholic Church in Falls Church, where she was a past president and treasurer of the church chapter of the Council of Catholic Women and a member of the Sodality, the Altar Society and the Women of St. James. She also was active in school organizations, including the St. James Mothers Club and the parents club at St. John's College High School.

Mrs. Martinelli was born in Avigliano, Italy. She moved to New York City in 1907. She worked there in the garment and millinery business before her 1927 marriage to Frank Martinelli. He died in 1966.

Survivors include two sons, James C. Martinelli of Vienna and Anthony A. Martinelli of Sudbury, Mass.; one sister, Mary LoPiccolo of Falls Church; 14 grandchildren, and one great-grandchild.

MARION L. WHITE,

79, an area resident since the 1940s who was a native of Massachusetts, died of cancer Dec. 20 at her home in Alexandria.

Survivors include her husband, retired Navy Capt. James J. White of Alexandria; two sons, Robert, of Williamsburg, and Christopher, of Alexandria; one brother, Edward Logan of New Haven, Conn., and three grandchildren.