A federal judge here yesterday rebuffed the Nuclear Regulatory Commission's effort to force a lawyer for an organization that investigates nuclear safety violations to divulge names of whistle-blowers who complained about problems with a Texas nuclear power plant.

U.S. District Court Judge Thomas F. Hogan said the NRC's subpoena of Billie Pirner Garde, a lawyer for the Government Accountability Project (GAP), violates the group's First Amendment right of association unless the government can prove that there are no other, less intrusive means of obtaining the information.

The NRC asked Hogan to order Garde to reveal the names of 46 whistle-blowers who came to GAP with information about possible safety violations at the South Texas Project, a nuclear power plant near Houston.

The whistle-blowers, workers at the plant and the NRC, said they wanted to reveal their information to the NRC but demanded assurances of confidentiality, including having their allegations investigated by NRC employes outside the region.

The NRC argued that it would keep the information confidential and subpoenaed Garde, calling on her to turn over "all allegations you have received concerning the safety of the South Texas Project" and "any records of other documents in your possession . . . concerning such allegations."

In his nine-page opinion refusing to enforce the subpoena, Hogan said "it is not unreasonable to infer from the fact that these whistle-blowers have gone to GAP that they do not wish their identities disclosed to the government without pledges of confidentiality acceptable to them."

He said he was "not much impressed by the government's argument that employes should not worry because federal law . . . prohibits retaliation against whistle-blowers."

He added, "From this point it is but a short step to the conclusion that if the government is successful in compelling Garde to reveal the information given to her, especially the identity of those she represents, GAP will lose the confidence of some of its whistle-blower informants and its efforts to gather and present safety allegations will suffer."

The NRC, Hogan said, "cannot cast with such a wide net when constitutional freedoms are at stake" and must "carefully and conscientiously" explore alternatives that minimize the intrusion on the First Amendment rights.

Thomas Mack, Garde's lawyer, called the ruling a "terrific decision . . . Nuclear workers are really protected under this."