Radiation Exposure Compensation Act Amendments of 2005 - Amends the Radiation Exposure Compensation Act to include specified counties in Montana among affected areas for purposes of payments to individuals with certain medical conditions who were exposed to fallout emitted during the U.S. government's atmospheric nuclear tests.

Allows residents in other counties in Montana to apply for compensation and requires the National Cancer Institute to evaluate eligibility on a case-by-case basis for such applicants.

Allows eligible individuals to receive additional compensation for the costs of screening, complications of screening, follow-up referrals, work-up diagnosis, and treatment related to the specific disease contracted by the individual.

Requires the Health Resources and Services Administration (HRSA) to conduct a program of education and communication about the health risks posed by radiation exposure from fallout from U.S. nuclear weapons testing.