Actions normally requiring an EIS are:

(a) Feasibility reports for authorization and construction of major projects;

(b) Proposed changes in projects which increase size substantially or add additional purposes; and

(c) Proposed major changes in the operation and/or maintenance of completed projects.

District commanders may consider the use of an environmental assessment (EA) on these types of actions if early studies and coordination show that a particular action is not likely to have a significant impact on the quality of the human environment.