Preparing Successful No-Effect and No-Adverse-Effect Section 106 Determinations: A Handbook for Transportation Cultural Resource Practitioners (2025)
Chapter: 1 Overview of the Section 106 Process
CHAPTER 1
Overview of the Section 106 Process
Figure 2 lays out the steps in the Section 106 process, the first of which is to initiate the process. As shown in this figure, consultation occurs in each step. As is discussed in more detail in Chapter 2, some of the decisions and actions included in initiating the Section 106 process, as laid out in 36 CFR Part 800.3 and listed herein, play an important role in making successful and defensible findings of No Effect and No Adverse Effect.
- Coordinating the steps in the Section 106 process with other required reviews, such as the National Environmental Policy Act (NEPA) (36 CFR Part 800.3 (b));
- Identifying the appropriate SHPO or THPO (if a project is on or contains tribal lands) and initiating consultation with the SHPO/THPO (36 CFR Part 800.3 (c));
- Developing a plan for public involvement (36 CFR Part 800.3(e)); and
- Identifying other consulting parties, including state-recognized tribes or tribal organizations (36 CFR Part 800.3(f)).
After the Section 106 process has been initiated, the next step is to identify historic properties (36 CFR Part 800.4). The critical elements of this step, in terms of successful and defensible findings of No Effect and No Adverse Effect, are determining the APE and identifying historic properties within the APE.
Identifying historic properties involves documenting properties in the APE that are already listed in the National Register, applying the National Register criteria for evaluation to unevaluated properties in the APE, and defining the aspects of integrity associated with historic properties. Determining the integrity of historic properties involves defining the essential physical elements (often referred to as “character-defining features”) of these resources. Application of National Register criteria and aspects of integrity are used to make decisions on whether or not an unevaluated property is National Register–eligible.
Completion of the identification of historic properties step in the Section 106 process results in one of two findings: a finding of No Historic Properties Affected or a finding that historic properties will be affected (36 CFR Part 800.4(d)). As noted earlier, a finding of No Historic Properties Affected is made when no historic properties are present in an APE or when historic properties are present but the undertaking will have no effect on these properties. As defined in 36 CFR Part 800.16(i), an “effect” is an alteration to the characteristics of a historic property that qualify it for inclusion in or eligibility for inclusion in the National Register.
If historic properties will be affected by a project, the next step in the process is to assess whether the project will have an Adverse Effect on these properties, in accordance with 36 CFR Part 800.5. This is done by applying the criteria of Adverse Effect laid out in 36 CFR Part 800.5(a)(1). The outcomes of this assessment are either a finding of No Adverse Effect or a finding of Adverse Effect. As shown in Figure 2, if there is a finding of Adverse Effect, the next step is to resolve the Adverse Effect. Resolution of Adverse Effects is not addressed in this
Figure 2. Steps of the Section 106 process.
handbook. More information and details on the Section 106 process, including resolution of Adverse Effects, are available in FHWA’s Section 106 tutorial (FHWA 2023b).
The next section discusses the different types of effects listed in the Section 106 regulations. This is followed by details of a series of steps for making successful and defensible findings of No Effect and No Adverse Effect. These steps are an outcome of the results of the online survey and interviews and generally follow the steps in the Section 106 process discussed earlier.
Definitions of Types of Effects
Successful and defensible findings of No Effect and No Adverse Effect need to be based on an understanding of the different types of effects that a project may have on historic properties. This is especially important when determining whether an effect is or is not adverse. As noted, an Adverse Effect may alter directly or indirectly any of the characteristics of a historic property
that qualify the property for inclusion in the National Register. In addition to these direct and indirect effects, an Adverse Effect may also include, as stated in 36 CFR Part 800.5(a)(1), “reasonably foreseeable effects caused by the undertaking that may occur later in time, be farther removed in distance, or cumulative.” The NHPA and Section 106 regulations do not provide definitions for these different types of effects; however, Attachment A in the Council on Environmental Quality (CEQ) and ACHP Handbook for Integrating NEPA and Section 106 (Handbook) does provide some definitions and guidance on these different types of effects:
Direct effects: A direct effect to a historic property would include demolition of a historic building, major disturbance of an archaeological site, or any other actions that occur to the property itself.
Indirect effects: Indirect effects that may change the character of the property’s use or of physical features within the property’s setting that contribute to its historic significance; are often audible, atmospheric, and visual effects; and may relate to viewshed issues. (CEQ and ACHP 2013)
The CEQ/ACHP Handbook compares and contrasts this definition of indirect effects with the following definition in the context of NEPA. The definition under the latter is as follows:
Reasonably foreseeable impacts that occur later in time or are further removed in distance from the proposed action. . . . These are often referred to as “downstream” impacts, or future impacts. (FHWA 2023a; emphasis added)
In terms of cumulative effects, the CEQ/ACHP Handbook provides the following for Section 106:
Cumulative effects: 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 (36 CFR Part 800.5(a)(1)). Although the Section 106 regulations do not define “cumulative effects,” the Council on Environmental Quality (CEQ) regulation definition of “cumulative impact” is analogous and instructive. (CEQ and ACHP 2013)
Attachment A, “Definitions and Translations,” of the CEQ/ACHP Handbook provides the following CEQ definition for cumulative impacts used in NEPA reviews:
The impact on the environment which results from the incremental impact of the action when added to other past, present, and reasonably foreseeable future actions regardless of what agency (Federal or non-Federal) or person undertaking such other actions. Cumulative impacts can result from individually minor but collectively significant actions taking place over a period of time [40 CFR Part 1508.7]. An individual action may not have much effect, but it may be part of a pattern of actions whose combined effects on a resource are significant. (CEQ and ACHP 2013; emphasis added)
Cumulative Impacts
Additional information on the nature of cumulative impacts in the context of NEPA reviews is provided on FHWA’s Environmental Review Toolkit website:
A cumulative impact includes the total effect on a natural resource, ecosystem, or human community due to past, present, and future activities or actions of Federal, non-Federal, public, and private entities. Cumulative impacts may also include the effects of natural processes and events, depending on the specific resource in question. Cumulative impacts include the total of all impacts to a particular resource that have occurred, are occurring, and will likely occur as a result of any action or influence, including the direct and reasonably foreseeable indirect impacts of a Federal activity. Accordingly, there may be different cumulative impacts on different environmental resources [Figure 3].
Cumulative impact analysis is resource specific and generally performed for the environmental resources directly impacted by a Federal action under study, such as a transportation project. However, not all of the resources directly impacted by a project will require a cumulative impact analysis. The resources subject to a cumulative impact assessment
Figure 3. Cumulative impact diagram..
should be determined on a case-by-case basis early in the NEPA process, generally as part of early coordination or scoping.
Cumulative impact analysis may be thought of as a comparison of the past, present, and reasonable foreseeable health or condition of a specific resource as described in the following air quality example.
The air quality of an area today is in a measurable condition, relative to the National Ambient Air Quality Standards (NAAQS). In the past, perhaps recently, the quality of the air may have been worse, the same, or better than it is today depending on a number of factors such as automobile use, industry, residential development (fireplaces), and climatic conditions. Each of these individual factors may have influenced the positive or negative change in the air quality of the area. The condition of the air today is the result of these factors, which constitutes the past effects of the cumulative impact question. Add the impacts of the proposed project, other occurring activities, and the positive and negative reasonably foreseeable impacts from any source (some of which may be indirect) and the result equates to the air quality cumulative impact.
In the NEPA process, a similar consideration or analysis would be performed for other resources potentially impacted by the implementation of a proposed project.
Source: FHWA (2023a).
Advisory Council on Historic Preservation 2019 Memorandum on Direct and Indirect Effects
ACHP (2019a) released a memorandum on June 7, 2019, on a court decision regarding the meaning of “direct” in both Sections 106 and 110(f) of the NHPA in the context of Adverse Effects on a National Historic Landmark (NHL). The memorandum notes that the court issued an opinion in National Parks Conservation Association v. Semonite concluding that
the meaning of the term “directly” in Section 110(f) refers to causality, and not physicality, of the effect. This means that if the effect comes from the undertaking at the time and place with no intervening causes, it is considered “direct” regardless of its specific type (e.g., whether it is visual, physical, auditory, etc.). “Indirect” effects are those caused by the undertaking that are later in time or farther removed in distance but are still reasonably foreseeable. (ACHP 2019a)
The memorandum states that the court decision “clarifies how effects in the Section 106 process may be defined as direct and indirect. Importantly, for both Section 106 and Section 110(f), the court recognized that visual effects on historic properties can be direct effects under NHPA.” The memorandum goes on to state that, although the court’s decision does not affect the application of Section 106, the decision does instruct how effects should be categorized in the Section 106 review process (ACHP 2019a).
The online survey and follow-up interviews that served as the foundation for this handbook asked state DOTs and SHPOs if the ACHP memorandum influenced their definitions and procedures for assessing effects on historic properties in the context of Section 106 reviews, especially in terms of the meaning of “direct” and “indirect” effects. The online survey results revealed much confusion on the applicability of the meaning of direct and indirect effects based on the ACHP memorandum, and this confusion was also reflected in the follow-up interviews. The interviews also showed that the memorandum prompted some state DOTs and SHPOs to think more about reasonably foreseeable and cumulative effects of undertakings, but the respondents noted that they had always thought about these types of effects to some degree before the memorandum was issued. As the ACHP memorandum is not taken into account in terms of current Section 106 decision-making among most state DOTs and SHPOs, and as ACHP has not provided guidance on the application of the memorandum (and the court’s decision) on Section 106 reviews, this handbook does not discuss this ACHP memorandum any further.
