Ray D. Walton Jr., 92, a nuclear engineer who managed research and development programs for the recovery of plutonium and uranium from spent nuclear fuels and for the handling of waste management, died April 8 at the Homewood retirement community in Frederick.

The cause was coronary heart disease, said a son, Rodney Earl Walton.

Mr. Walton, who retired in 1986, spent most of his career at what became the U.S. Energy Department. As a young man, he helped design the engineering-scale waste solidification facility — one of the world’s first — at the Idaho Falls test site for what was the Atomic Energy Commission.

From 1964 to 1966, he was an international nuclear fuel cycle expert for the International Atomic Energy Agency in Vienna, Austria.

After his federal retirement, he spent a decade working part-time as a waste consultant for Argonne National Laboratory’s office in the Washington area. He received a lifetime achievement award from the Waste Management Symposium, a professional organization.

Ray Daniel Walton Jr. was born in Ogden, Utah, and raised in Portland, Ore. He was a 1943 graduate of Oregon State University, where he also received a master’s degree in chemical engineering in 1948.

He spent his early career as a nuclear engineer with General Electric in Washington state.

He served in the Army in the Pacific during World War II and participated in the invasion of Okinawa. His decorations included the Bronze Star Medal and the Purple Heart.

He was a member of Mountain View United Methodist Church in Damascus, where his first wife had once served as pastor. He moved to Frederick from Damascus in 2010.

His first wife, the former Carolyn Smith, died in 1984 after 39 years of marriage.

Survivors include his wife since 1997, Frances Crabill Walton of Frederick; six children from the first marriage, Rodney Earl Walton of Miami, W. Scott Walton of Churchville, Md., Eric B. Walton of Ballston Lake, N.Y., Kip M. Walton of Hartland, Mich., Trudy Schwarz of Derwood, Md., and James D. Walton of Irvine, Calif.; 16 grandchildren; and three great-grandchildren.

— Adam Bernstein