James Richard (Dick) Cullins, 66, a retired construction inspector for the Washington Suburban Sanitary Commission who was active in youth groups, died of cancer Monday at Physicians Memorial Hospital in La Plata, Md.

Mr. Cullins was born on a farm in St. Mary's County, Md., and grew up in Washington. He attended McKinley Technical High School. In 1935, he went to work at the old Naval Gun Factory as a toolmaker and remained there until 1960. For the next 10 years, he was employed by Engineering Physics, a Rockville firm engaged in subcontracting for the government. From 1970 until his retirement last year, he was a construction inspector for the WSSC.

In 1956, Mr. Cullins helped found the Silver Hill (Md.) Boys Club. He was the director of the organization for 13 years and coached baseball and basketball teams there. In the early 1970s, he organized and coached American Legion baseball teams in Clinton and Oxon Hill.

Mr. Cullins lived in Hillcrest Heights until moving to White Plains, Md., about eight years ago. He was a member of Christ Episcopal Church in Clinton.

Survivors include his wife, Evelyn M., of White Plains; one son, Richard B., of Pasadena, Md.; two brothers, John Wallace Cullins of El Paso, Tex., and William A. Cullins of Lanham, and one grandchild.