The Senate Public Works Committee has decided that the planned move of the Nuclear Regulatory Commission to downtown Washington must be restudied with full consideration for finding a site in Montgomery County, where most of the agency's 2,400 employes work and live.

Sen. Daniel P. Moynihan (D-N.Y.), chairman of the committee's ad hoc subcommittee on public grounds, said last night that the General Services Administration did not give sufficient weight to the possibility of a location in the suburban county where eight of the agency's nine offices are now scattered.

A letter being sent to the GSA today orders a review be completed within 60 days so the committee can decide between a location in the city or the suburb.

"This doesn't absolutely mean NRC will be located in Montgomery County," a jubliant Rep. Newton I. Steers (R-Md.) said after Moynihan notified him of the decision, "but downtown D.C. has been rejected for the time being."

Steers, who was among witnesses testifying Tuesday against the planned move, said Moynihan said "he was convinced by the testimony that the GSA study had not considered consolidating in Montgomery."

Montgomery County Executive James P. Gleason testified Tuesday that the county's Department of Economic Development was not consulted by the GSA.

"Four sites adjacent to a transit station (the Metro in Silver Spring) could be available at less cost and within the same time" as securing a location downtown, Gleason testified.

Gleason, Steers, Sen. Paul S. Sarbanes (D-Md.) and leaders of two employe unions argued that, GSA had not considered the "human factor" in going ahead with plans to relocate the agency downtown. About 80 percent of NRC's employes live in Maryland, two-thirds in Montgomery County.

NRC was created as an independent agency in 1974, taking over the licensing and regulatory functions formerly assigned to the Atomic Energy Commission. All but 200 of its nearly 2,400 employes work in Montgomery County, in Bethesda, Silver Spring and Rockville.

The Senate Committee on Environment and Public Works, and its counterpart, the House Public Works Committee, have unique authority in deciding the location of federal installations, a staff employe said. Committee action is final, and does not require approval by the full Senate or House.

The House committee already has approved relocating NRC in the District, so if the Senate should pick a site in Montgomery, the two committees would have to get together and resolve the problem.

NRC Chairman Joseph M. Hendrie testified that the agency would "operate most efficently and effictively from a location in downtown Washington."

District officials are hoping NRC will lease one or two new buildings that would be constructed in an urban renewal site. Such a decision, according to Lorenzo W. Jacobs, director of the District's Department of Housing and Community Development, would be in keeping with President Carter's new urban policy and could lead to "a major transformation of the old downtown."