39 C.F.R. § 775.4
Approving official means the person or group of persons, who authorizes funding as established through the delegations of approval authority issued by the finance organization. That person or group of persons may not have proposed the action for which financial approval is sought.
Environmental checklist means a Postal Service form that identifies potential environmental impacts for proposed actions initiated by postal managers.
Mitigated FONSI means a FONSI which requires the implementation of specified mitigation measures in order to ensure that there are no significant impacts to the environment.
Record of environmental consideration means the Postal Service form that identifies the Postal Service's review of proposed activities under NEPA.
Responsible official means the person, or designated representative, who proposes an action and is responsible for compliance with NEPA. For larger projects, that person may not have the financial authority to approve such action. The responsible official signs the NEPA documents (FONSI, ROD) and the REC.
39 C.F.R. §775.4