Harold H. Leich, 72, a retired chief of the policy development division of the old Civil Service Commission and a lifelong outdoorsman and conservationist, died Wednesday at George Washington University Hospital. He had a brain tumor.

Mr. Leich, who was born in Evansville, Ind., was a member of the class of 1929 at Dartmouth College, where he was elected to Phi Beta Kappa. He later earned a master's degree in public administration at American University.

He began his career with the Civil Service Commission, now the Office of Personnel Management, in 1935. He was an organizer of the commission's standards division and its first chief. He worked on what became the Intergovernmental Personnel Act and was a member of the task force that organized the Environmental Protection Agency. He was head of the chief of the policy division at the time of his retirement in 1972.

In 1963, Mr. Leich received the Commissioners Award for Distinguished Service.

As an outdoorsman, Mr. Leich was a white-water canoeist, a kayak enthusiast, a hiker and a skier. In 1933, he made a trip down the Colorado River. He described that experience in "Shipwrecked in Cataract Canyon," a book he wrote that is scheduled for publication next year.

In 1951, when he was chairman of the recreation committee of the Interstate Commission on the Potomac River, he wrote the first canoeing guide to the Potomac. For many years he maintained a section of the Appalachian Trail in the Shenandoah National Park. He was a former president of the Washington Ski Club.

Mr. Leich's particular environmental interest was water pollution. He was elected chairman of the workshop on protection of ground waters, rivers, lakes and estuaries and oceans at the U.N. Environmental Conference at Stockholm, Sweden, in 1972. He attended subsequent meetings elsewhere in the world. At the time of his death, he was treasurer of the Environment Fund, a nonprofit group of which he was a founder, and of the Council of Washington Representatives on the United Nations.

Mr. Leich's first wife, the former Cora Louise McIver, died in 1971.

Survivors include his wife, the former Marian Lloyd Nash, of Washington; two sons by his first marriage, Harold McIver Leich of Champaign, Ill., and Jerffrey Renwick Leich of North Conway, N.H.; two brothers, Alexander L. of Evansville and Roland J. of Pittsburgh, and one sister, Mrs. Paul C. Reardon of Hingham, Mass.

The family suggests that expressions of sympathy be in the form of contributions to the Land Acquisition Fund of the Potomac Appalachian Trail Club, to the St. John's Child Development Center, or to the American Cancer Society.