12 CFR § 1815.109 - Preparation of an EIS.
(a) If the Fund determines that an EIS should be prepared, it shall publish a notice of intent in the Federal Register in accordance with 40 CFR 1501.7 and 1508.22 of the CEQ regulations. After publishing the notice of intent, the Fund shall begin to prepare or have prepared the EIS. Procedures for preparing the EIS are set forth in 40 CFR part 1502 of the CEQ regulations.
(b) The Fund may supplement a draft or final EIS at any time. The Fund shall prepare or have prepared a supplement to either the draft or final EIS when:
(1) Substantial changes are proposed to an action contained in the draft or final EIS that are relevant to environmental concerns or there are significant new circumstances or information relevant to environmental concerns and bearing on the proposed action or its impacts; or
(2) Actions are proposed which relate or are similar to other action(s) taken or proposed and that together have a cumulatively significant impact on the environment.