40 CFR § 1.21
General
June 9, 2020
EPA Headquarters is comprised of:
(a) The Office of the Administrator;
(b) Two Associate Administrators and four staff offices which advise the Administrator on cross-cutting Agency headquarters and regional issues and conduct programs with respect to EPA's interface with other national and international governmental organizations;
(c) The Office of Inspector General;
(d) The Office of General Counsel; and
(e) Nine operational offices, each headed by an Assistant Administrator, responsible for carrying out EPA's major environmental and administrative programs.