TIER 1 (Stages 1 - 3) A National Environmental Policy Act (NEPA) corridor-level analysis that is completed for large studies that require certain broad questions be answered before a more-detailed study (a Tier 2 analysis) can be done

TIER 2 (Stages 4 & 5) National Environmental Policy Act (NEPA) project-level analysis that focuses on specific sections identified in Tier 1.

See the process and schedule graphic.

Stage 1

Stage 1: Initiation

Work Plan:
A detailed guide for implementing the Tiered Environmental Impact Statement process

Agency/Community Agreements:
An agreement that documents the desire of involved parties to engage in a particular course of action

Notice of Intent (NOI):
A federal announcement, printed in the federal register, advising interested parties that an environmental impact statement will be prepared and circulated

Stage 1 Completed 2005


Stage 2

Stage 2: Scoping

Identification of key issues and ideas for alternatives

Resource Methodologies and Baseline Data Collection:
A determination of what environmental information is needed and how it will be collected

Purpose & Need:
Definition of why the project is needed and what the alternatives must accomplish

Initial Alternatives Development:
Consideration of broad range of possible alternatives

Community Workshops:
Educational seminars emphasizing interaction and exchange of information among a small group of participants

Range of Corridor Location Alternatives:
All reasonable corridor location alternatives that must be rigorously explored and objectively evaluated

Role of Public Input:
Identify issues to be addressed

Stage 2 Completed 2006

Stage 3

Stage 3: Corridor Evaluation & Documentation

Detailed Alternatives Development:
Detailed planning and conceptual engineering for remaining alternatives

Environmental Impacts Analysis:
Detailed assessment of potential impacts associated with each alternative, including social, economic, and natural environmental impacts

Alternatives Screening:
Application of specific criteria to determine alternatives to be studied in greater detail in Environmental Impact Statement

We are here
Draft Tier 1 Environmental Impact Statement (DEIS)—released in May 2016:
Preparation and release of document disclosing all anticipated impacts associated with each alternative for public and agency review

Preferred Corridor Alternative:
The alternative for a corridor location and facility type are chosen based on the project's purpose and need and the requirements of the agencies involved

Final Tier 1 Environmental Impact Statement (FEIS) and Record of Decision (ROD):
A concise decision document for an EIS that states the decision, other alternatives considered, and mitigation adopted for the selected alternative or choice

The Combined Final Tier 1 EIS and ROD will also respond to public comments on the Draft Tier 1 EIS and identify segments of independent utility.

Role of Public Input:

  • Help refine alternatives to minimize impacts
  • Endorse criteria for screening

• Comment on the Draft and Final Environmental Impact Statements

We are here at Stage 3 - Started 2006

Stage 4

Stage 4: Project-Specific Scoping & Evaluation

Project-Specific Purpose & Need:
Why the project is needed and what the alternatives must accomplish

Project-Specific Alternative:
Based on the decisions reached during the Tier 1 process, FHWA and CDOT may proceed with Tier 2 studies for specific projects within those segments
All reasonable alternatives in a specific location must be rigorously explored and objectively evaluated

Preferred Project-Specific Alternative:
The alternative that fulfills the applicant agency's statutory mission and achieves the project's stated Purpose & Need

Role of Public Input:
Input on Environmental Evaluation and Documentation and Preferred Project-Specific Alternative

Future: As funding is identified/secured for specific projects


Stage 5

Stage 5: Project-Specific Documentation

Decision Document:
Categorical Exclusion

Finding of No Significant Impact

Record of Decision

Role of Public Input:
The degree of public input sought will depend upon the type of decision document required

Environmental Documentation will be developed as appropriate for the level of impacts involved

Future: As funding is identified/secured for specific projects