A Brief Explanation of NEPA and Section 106 Reviews

The National Historic Preservation Act (NHPA) and the National Environmental Policy Act (NEPA) are two separate laws which require federal agencies to “stop, look, and listen” before making decisions that impact historic properties and the human environment.

NHPA was signed into law in 1966, and Section 106 of the NHPA requires federal agencies to take into account the effect of undertakings they carry out, license, approve, or fund on historic properties and provide the Advisory Council on Historic Preservation (ACHP) a reasonable opportunity to comment before making decisions. Using the Section 106 process, agencies identify historic properties, assess effects to historic properties, consider alternatives to avoid, minimize, or mitigate any adverse effects, and document their resolution. Agencies are required to facilitate a stakeholder engagement process known as consultation – discussing and considering the views of consulting parties, including State Historic Preservation Officers (SHPOs) and/or Tribal Historic Preservation Officers (THPOs), Indian tribes, Native Hawaiian organizations, and others, while also providing opportunities for public input. The ACHP, an independent federal agency established by the NHPA, oversees the implementation of the Section 106 process, issues its implementing regulations (36 CFR Part 800), and may participate in consultation to resolve adverse effects to historic properties.

NEPA was signed into law in 1970 and requires federal agencies to assess whether a major federal action has the potential to significantly affect the human environment prior to making decisions. Using the NEPA process, agencies evaluate the environmental and related social and economic effects of their proposed actions. This is done through preparation of an Environmental Assessment or an Environmental Impact Statement. NEPA is often described as an “umbrella” law as its analysis incorporates a broad range of federal laws, regulations, and executive orders.  Under NEPA, agencies are required to provide opportunities for public review and comment, so the agency may consider those comments. NEPA established the President's Council on Environmental Quality (CEQ) to oversee NEPA implementation. In 1978, CEQ issued regulations (40 CFR Parts 1500-1508) to implement NEPA.

Integration of NEPA and Section 106 Reviews

Federal agencies’ statutory obligations under NEPA and NHPA are independent, but integrating the processes creates efficiencies, promotes transparency and accountability, and supports a broad discussion of effects to the human environment. CEQ and the ACHP developed a handbook to promote better integration of the two review processes, and ACHP offers e-learning courses on the Basics of NEPA and Section 106 Integration and Coordinating NEPA and Section 106.

Section 106 review should be complete prior to issuance of a federal decision, so that a broad range of alternatives may be considered during the planning process. Because the information gathering and consultation done in the Section 106 review should inform the NEPA review, and vice versa, the timing of both reviews should be coordinated. For example, a finding of adverse effect under Section 106 may help determine whether “extraordinary circumstances” exist that would prevent an agency from utilizing a categorical exclusion from NEPA for a particular action.

Integration of NEPA and Section 106 should begin early, to enhance agency planning. Integration of NEPA and Section 106 makes sense because: the historic properties of concern in Section 106 are one type of resource in the human environment considered in NEPA; both processes are triggered by federal funding, permits, licenses, or other approvals and share goals of providing transparency and allowing for public involvement; both processes should be initiated early in project planning when a broad range of alternatives can be considered; and, completion of both processes is needed for agencies to proceed to implement an action or undertaking. In addition, agencies are encouraged to combine public involvement efforts for the two reviews to avoid duplication of effort and to maximize opportunities for public and consulting party involvement.

The ACHP-CEQ handbook includes flowcharts to clarify timing and communication touchstones for Section 106 with NEPA. The handbook also includes guidance to help agencies substitute the NEPA process for Section 106 through a procedure specified in the Section 106 regulations (36 CFR § 800.8(c)).

How Key Terms are Defined in NEPA and Section 106 Reviews

Undertaking is a project, activity, or program funding in whole or in part under the direct or indirect jurisdiction of a federal agency, including those carried out by or on behalf of a federal agency; those carried out with federal financial assistance; and those requiring a federal permit, license or approval. The undertaking is generally the project that requires some federal action to move forward. Major Federal Action includes activities entirely or partially financed, assisted, conducted, regulated, or approved by Federal agencies. Federal actions include adopting policies such as, rules or regulations; adopting plans; adopting programs; or approving projects; ongoing activities; issuing permits; or financing projects completed by another entity
Historic Property is one which is included in or eligible for inclusion in the National Register of Historic Places. Properties of traditional religious and cultural importance to an Indian tribe or Native Hawaiian organization may be eligible for inclusion or listed in the National Register. Cultural Resource covers a wider range of resources than “historic properties,” such as sacred sites, archaeological sites not eligible for the National Register, and archaeological collections.
Adverse Effect is found when an undertaking may alter, directly or indirectly, any of the characteristics of a historic property that qualify the property for inclusion in the National Register, in a manner that would diminish the property’s integrity. Adverse effects may include reasonably foreseeable effects caused by the undertaking that may occur later in time, be farther removed in distance, or be cumulative. Significant Impact is determined based on context and intensity. Impacts are analyzed in several contexts such as society as a whole, the affected region, the affected interests, and the locality. Intensity refers to the severity of effect, which includes factors such as the magnitude, geographic extent, duration, and frequency of the effect.
Mitigation is a type of measure to resolve specific adverse effects to identified historic property or properties by offsetting such effects. Mitigation should relate to the historic property’s significance and address the nature of the adverse effect(s). Mitigation measures are considered after avoidance and minimization alternatives. Mitigation includes avoiding the impact altogether by not taking a certain action or parts of an action; minimizing impacts by limiting the degree or magnitude of the action and its implementation; rectifying the impact by repairing, rehabilitating, or restoring the affected environment; reducing or eliminating the impact over time by preservation and maintenance operations during the life of the action; and compensating for the impact by replacing or providing substitute resources or environments.



Integrating NEPA and Section 106 reviews improves efficiency and informed decision making.