Department leaders last month uncovered more than $100 million in duplicate government payments for medical services.
About 80% of VA's roughly 450,000 employees are union members, but the department will no longer honor its contracts with the bargaining units.
GOP lawmakers are pushing reforms for a host of department employee financial incentives, but Democrats worry the moves will hurt recruiting efforts.
More than 17,000 Veterans Affairs jobs have been eliminated or vacated since the start of the year.
