A U.S. Senate committee decided last week to build the new Nuclear Regulatory Commission headquarters at an as yet undetermined site in Silver Spring rather than in the District of Columbia.

Officials from D.C. and Montgomery County have been vying for several years to attract the proposed NRC headquarters. The NRC presently maintains facilities in Bethesda, Rockville, Silver Spring and downtown Washington, but federal officials want all NRC offices located in one place.

The new NRC headquarters will be built in three to five years at a cost of $113 million. A House committee still must formally approve its construction, but the House is not expected to contest the selection of a site in Silver Spring.

Daniel Patrick Moynihan, a member of the Senate Committee on Environment and Public Works, has said that he wanted the new headquarters to be in Silver Spring because most NRC employes already work in Silver Spring. The vote of the Senate committee was unanimous.

Before the new headquarters is constructed, about 1,000 NRC employes will move temporarily to downtown Washington so they can work with the 152 NRC commissioners who have offices on H Street NW.

A spokesman for Rep. Michael D. Barnes (D-Md.) said the Montgomery County congressman will urge members of Congress and the Carter administration to halt the temporary move because it would be "wasteful." A General Services Administration report estimates the temporary move would cost $3 million and take 18 months. Then the employes would return to Silver Spring after the new headquarters is constructed.