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Chapter 33 - Reevaluations

What Does the Topic Include?

This chapter discusses the circumstances that trigger the need for consultation and reevaluation of National Environmental Policy Act (NEPA) documentation, the reporting and processing requirements, and how to keep the project in NEPA compliance when a project changes during construction. As a highway project proceeds in its development from environmental review through construction, there may be circumstances that could affect the validity of its NEPA documentation or approval. The Federal Highway Administration (FHWA) regulations to implement NEPA (23 CFR 771) and Technical Advisory T6640.8A provide direction on determining when a project's NEPA documentation must be re-examined.  

Laws, Regulations, and Guidance - Refer also to Chapter 1 - Federal Requirements

Background Reevaluation and Consultation

The FHWA NEPA regulations specify that a federal agency must prepare a supplemental Environmental Impact Statement (EIS) if there are substantial changes to the project or there are significant new circumstances or information relevant to environmental issues.  The FHWA NEPA regulations, 23 CFR 771.129, also set forth the requirements and a timeframe for written evaluations of EISs and for consultation procedures for all types of NEPA documentation, including Categorical Exclusions (CEs), Findings of No Significant Impacts (FONSIs), draft, final, and supplemental EISs. The text of the regulation is given below:

§ 23 CFR 771.129 Re-evaluations.

(a) The applicant must prepare a written evaluation of the draft EIS, in cooperation with the Administration, if an acceptable final EIS is not submitted to the Administration within three years from the date of the draft EIS circulation. The purpose of this evaluation is to determine whether or not a supplement to the draft EIS or a new draft EIS is needed.

(b) The applicant must prepare a written evaluation of the final EIS before the Administration may grant further approvals if major steps to advance the action (e.g., authority to undertake final design, authority to acquire a significant portion of the right-of-way, or approval of the plans, specifications and estimates) have not occurred within three years after the approval of the final EIS, final EIS supplement, or the last major Administration approval or grant.

(c) After the Administration issues a combined final EIS/ROD [Record of Decision], ROD, FONSI, or CE designation, the applicant must consult with the Administration prior to requesting any major approvals or grants to establish whether or not the approved environmental document or CE designation remains valid for the requested Administration action. These consultations will be documented when determined necessary by the Administration.

(d) For tiered EAs [Environmental Assessments] or EISs, if the second tier occurs 5 or more years after the first tier document, the applicant in consultation with the Administration, must re-evaluate the analysis and any underlying assumptions of the first tier EIS or EA to ensure reliance on the analysis remains valid.

Historically, the term "reevaluation" has been used generically to refer both to the process and to the document produced under 23 CFR 771.129. While most of time the meaning is understood, this mixed use of the term has led to some misunderstandings about which types of NEPA documentation need to be re-assessed and when. Consultation applies to all NEPA documentation [23 CFR 771.129(c)], whereas a written evaluation, with its 3-year timeframe, applies only to an EIS [23 CFR 771.129(a) and (b)]. To document consultation or re-validation of CEs and FONSIs, as well as to serve as a written evaluation of an EIS, a NEPA/CEQA Re-validation form has been developed.

Triggers for Consultation or Reevaluation

There are three triggers that necessitate the initiation of the consultation or reevaluation process:

  1. Project is proceeding to the next major federal approval
  2. Project changes
  3. Three year timeline for an EIS

All reevaluations should include a site visit (if appropriate) and evaluation by a qualified environmental generalist and any technical specialists deemed necessary. Assessments by technical specialists should be prepared for any topical areas affected by a change in the project, its surroundings, new information or requirements, or other factors that may cause the original evaluation to no longer be valid. Additional studies and/or coordination with other agencies should be conducted as appropriate.

Project Proceeding to Next Major Federal Approval

Following the approval of a CE determination, a FONSI, or an EIS, 23 CFR 771.129(c) provides that Caltrans must consult (ensure that the original environmental document/determination is still valid) prior to requesting any major approvals from FHWA (e.g., authority to undertake final design, authority to acquire a significant portion of the right-of-way, or approval of the plans, specifications and estimates [PS&E]). The purpose of this consultation is to establish whether or not the approved NEPA environmental determination/document remains valid for the requested federal approval. 

Documenting the Outcome

  • If the original NEPA determination/document remains valid, the first line under the NEPA conclusion section of the NEPA/CEQA Re-Validation Form is checked and the project can proceed. When the NEPA conclusion is still valid from a previously prepared NEPA/CEQA Re-Validation form, the signed Environmental Certification form can be used as the required written documentation of consultation to satisfy 23 CFR 771.129(c) at Ready to List (approval of PS&E) or if the 12-month expiration date has passed. 
  • If additional informational documentation is needed to maintain the validity of the form but does not require the preparation of a new or higher level document, mark the second line on the NEPA/CEQA Re-validation form and complete the continuation sheet(s) as needed to maintain the validity of the original document.
  • If a new or supplemental environmental document/determination must be prepared, check the appropriate boxes on the NEPA/CEQA Re-validation form and proceed accordingly. Refer to Chapter 30, Categorical Exclusion (CE); Chapter 31, Environmental Assessment (EA)/Finding of No Significant Impact (FONSI); or Chapter 32, Environmental Impact Statement (EIS).

Project Changes

Although project changes are not specifically called out in 23 CFR 771.129, they can be important triggers for reevaluation. They are treated as a trigger because if the changes are not dealt with proactively, they can lead to project delay and delivery failure. Project changes can occur at any time in the project development process. Examples of project changes include: changes in project engineering/design; changes to the environmental setting/circumstances, including changes in laws and regulations; changes in nature and severity of environmental impacts; changes to environmental commitments--avoidance, minimization, and/or mitigation. Based on the nature and severity of the changes, the determination will be made whether: 1) the original CE determination, FONSI, or EIS is still valid, and whether the project may proceed; 2) additional documentation is needed to maintain the validity of the original CE determination, FONSI or EIS due to changes in project scope, circumstances or environmental requirements but does not require the preparation of a new or higher level document; or 3) the original environmental document/determination is no longer the appropriate determination or document and some other document must be prepared.

Documenting the Outcome

  • If the original CE determination, FONSI, or EIS remains valid, check the first line under the NEPA conclusion section of the NEPA/CEQA Re-Validation Form and proceed with the project.
  • If additional informational documentation is needed to maintain the validity of the form but does not require the preparation of a new or higher level document, mark the second line on the NEPA/CEQA Re-validation form and complete the continuation sheet(s) as needed to maintain the validity of the original document.
  • If a new or supplemental environmental document/determination must be prepared, check the appropriate boxes on the NEPA/CEQA Re-validation form and proceed accordingly. Refer to Chapter 30, Categorical Exclusion (CE); Chapter 31, Environmental Assessment (EA)/Finding of No Significant Impact (FONSI); or Chapter 32, Environmental Impact Statement (EIS).

Three-Year Timeline for an EIS

Draft EIS

In accordance with 23 CFR 771.129(a) and (b) and Technical Advisory T6640.8A, a written evaluation of a draft EIS (DEIS) is required if the final EIS has not been approved within three years of the circulation of the DEIS. In this circumstance, the DEIS is subject to a written evaluation of its validity. While the entire project must be re-examined for changes, an evaluation of a DEIS should focus on any changes to the project, its setting, impacts, or new issues that have arisen since the circulation of the document. Based on the written evaluation, a decision is made whether to document that the existing DEIS remains valid, to supplement the existing DEIS, or prepare a new DEIS. 

Documenting the Outcome

The NEPA/CEQA Re-validation form is used to document the determination of whether: 1) the original DEIS remains valid, or 2) additional documentation is needed to keep the document valid, or 3) a supplemental EIS or a new DEIS is required. If Caltrans, specifically the Environmental Branch Chief/Manager, concludes that a supplemental EIS or a new DEIS is required, proceed accordingly (refer to Chapter 32, Environmental Impact Statement).

Final EIS

The regulations and Technical Advisory require a written evaluation of a final EIS if major steps to advance the project have not occurred within three years of the approval of the final EIS, final EIS supplement, or the last major FHWA approval. The purpose of the written evaluation is to determine whether the EIS remains valid or whether a new or supplemental EIS is required. Again, this is based on whether there have been changes such as those listed above for the DEIS. While the entire project must be re-examined for changes, an evaluation of a final EIS should focus on any changes to the project, its setting, impacts, or new issues that have arisen since the circulation of the document. Based on the written evaluation, a decision is made whether to document that the existing final EIS remains valid, to supplement the existing final EIS, or prepare a new final EIS.

Documenting the Outcome

The NEPA/CEQA Re-validation form is used to document the determination of whether: 1) the original DEIS remains valid, or 2) additional documentation is needed to keep the document valid, or 3) a supplemental EIS or a new DEIS is required. If Caltrans, specifically the Environmental Branch Chief/Manager, concludes that a supplemental EIS or a new DEIS is required, proceed accordingly (refer to Chapter 32, Environmental Impact Statement).

Internal Review and Approval for Consultation/Reevaluation

As discussed in the Triggers for Consultation or Reevaluation section above (specifically the "Documenting the Outcome" subsections), documentation of consultations/reevaluations is done by completing the NEPA/CEQA Re-validation Form. The District Environmental Branch Chief in consultation with the Project Manager and the Project Development Team has overall responsibility for ensuring that consultation and/or reevaluation is completed. There is no mandated HQ review during consultation/reevaluation; care should be taken, however, to check the district's Quality Control Plan regarding district procedures for consultation/reevaluations. In accordance with the signature authorities established under NEPA Assignment, approval of the consultation/reevaluation requires the signature of an Environmental Branch Chief/Manager. After documenting approval of the consultation/reevaluation by completing the NEPA/CEQA Re-validation form, the approved NEPA/CEQA Re-validation form must be placed in project file.

Public Circulation of a Reevaluation

Neither the documented results of a consultation nor a written evaluation requires public circulation. However, it is a part of the project files, and as such it is a public document.

New or Supplemental Environmental Document

If the reevaluation process results in a decision to prepare a document that is distributed to the public, such as a new or supplemental EIS, a brief summary of the reevaluation process should be included in that document. The public circulation and review would follow the same process as that for a new EA or EIS. See as applicable, Standard Environmental Reference, Volume 1, Chapter 31 Environmental Assessments or Chapter 32 Environmental Impact Statements.

(Last content update: 08/04/2025 JH)