The FMCSA is proposing to revise its regulatory oversight of Mexico-domiciled Commercial Motor Carriers (CMC) through a series of four rulemakings. The purpose of the four proposed rules is to protect the health and safety of the general public, by ensuring that Mexico-domiciled CMC are willing and able to comply with United States requirements and by monitoring their compliance once they commence United States operations. The rules would be promulgated by FMCSA as part of a larger effort to assess and monitor the safety performance of Mexico-domiciled CMC operating in the United States. To satisfy the requirements of the National Environmental Policy Act (NEPA), FMCSA, with the assistance of the Volpe National Transportation Systems Center, prepared a Programmatic Environmental Assessment (PEA) to assess the impacts of the proposed rules. The PEA follows the procedures established by the Department of Transportation (DOT) to implement NEPA, pursuant to the Council on Environmental Quality (CEQ) regulations. The PEA is intended to be a decision tool that will be used by FMSCA to make informed decisions and to fully understand the environmental ramifications of those decisions. The PEA addresses the consequences of the four proposed rules on human and natural environments, suggests potential mitigation of adverse impacts, and analyzes the no-action alternatives to the proposed actions.