Sen. John W. Warner (R-Va.) said yesterday that he will hold hearings when Congress reconvenes to investigate whether a provision that he inserted into a defense bill in September has hurt veterans who were exposed to atomic radiation.

The law strips the veterans of their right to sue defense contractors who participated in the 693 atomic tests that the government is known to have conducted between 1945 and 1980. It also makes it difficult for civilians who were exposed to fallout in the tests to sue. It is believed that during the tests, more than 1 million Americans were exposed to radiation, high doses of which can cause cancer.

Warner said he proposed the amendment after Energy Department officials told him that the Veterans Administration was compensating veterans for radiation-related health problems.

But the National Association of Radiation Survivors (NARS) and others have contended that the VA is not compensating these so-called "atomic veterans." Records show that of the 4,407 disability claims fielded by these veterans, all but 14 have been denied by the VA on the grounds that it is impossible to prove that veterans' cancers were caused by radiation.

"If it is not clear that veterans are adequately protected by the administrative remedies or procedures allegedly offered, I will consider either amending or repealing that provision of legislation adopted during the last session of Congress," Warner said yesterday.