40 CFR 1508.19 - Matter.
Matter includes for purposes of part 1504:
(a) With respect to the Environmental Protection Agency, any proposed legislation, project, action or regulation as those terms are used in section 309(a) of the Clean Air Act (42 U.S.C. 7609).
(b) With respect to all other agencies, any proposed major federal action to which section 102(2)(C) of NEPA applies.