The main purpose of this legislation is to eliminate a specific part of the Clean Air Act that deals with environmental and climate justice block grants. The bill aims to repeal section 138 of the Clean Air Act, which was designed to provide funding to support projects that promote environmental justice and address climate-related issues in underserved communities. Key provisions of this legislation include the outright repeal of section 138, which means that any funding and programs associated with environmental and climate justice block grants will no longer exist.