27 C.F.R. § 19.695
When a proprietor permanently discontinues operations as an alcohol fuel plant, the proprietor must file a letterhead notice with the appropriate TTB officer along with the following:
(c) A report on form TTB 5110.75, Alcohol Fuel Plant Report, covering the discontinued operations, with the report marked “Final Report”.
(26 U.S.C. 5181, 5271)