Supplemental Environmental Assessments.
1 C.F.R. § 601.17
in effectEffective: 2024-07-01(a) The NCPC shall prepare a supplemental EA if five or more years have elapsed since adoption of the EA and:
(1) There are substantial changes to the proposed action that are relevant to environmental concerns; or
(2) There are significant new circumstances or information that are relevant to environmental concerns and have a bearing on the proposed action or its impacts.
(b) The NCPC may supplement a Draft or Final EA at any time to further the purposes of NEPA.
(c) The NCPC shall prepare, circulate, and file a supplement to a Draft or Final EA, and adopt a FONSI in accordance with the requirements of §§ 601.15 and 601.16. If NCPC is not the Lead Agency, it shall proceed as outlined in § 601.16(b) and (c).
Source: eCFRURL: https://www.ecfr.gov/api/versioner/v1/full/2024-07-01/title-1.xmlFetched: 7/26/2026
