What is environmental permitting?
EPA's permit programs come from six statutes, including the Clean Air and Clean Water Acts; many states, tribes and municipalities run them under EPA oversight[1]. In California, a permit for an activity that may change the environment makes it a CEQA project[9], and other state laws require similar review[10].
How NEPA affects environmental permitting
NEPA, the federal form of environmental impact assessment, covers major federal actions, and a permit decision usually is one[11]. Under the Corps' procedures, in force since July 3, 2025, most permits without a categorical exclusion need only an EA. Until the review ends, the applicant should take no action that limits the choice of reasonable alternatives[2][8].
Not every federal permit triggers NEPA. Clean Air Act actions don't count as major federal actions significantly affecting the environment[12], and neither do EPA's Clean Water Act actions, except new-source NPDES permits and treatment works grants[13]. When several agencies must act, they use one document where practicable[14].
The usual federal permits and consultations
FHWA's November 2025 FONSI for rebuilding 0.7 mile of U.S. 75 through Hinton, Iowa, lists five permits it will likely need: a Corps Section 404 permit, Iowa DNR's Section 401 certification and NPDES stormwater permit, and state and city floodplain permits. Because two buildings in a historic district will come down, FHWA, Iowa DOT and the Iowa SHPO also signed a Section 106 agreement[15].
A Corps NEPA document may list these and how the applicant will meet them[8]; the checklist below covers the usual ones.
Environmental planning and permitting: the steps in order
Coordination starts before the application: Corps regulatory staff advise potential applicants on the studies and information later federal action will need[2]. For the planner's side, see environmental planning.
The NEPA decision document informs the permit decision but is not the final agency action[8]. Once a permit issues, its monitoring and reporting conditions carry into construction and operation[1].