4.1.1

provide the policy and procedures for how the NPS will comply with NEPA. The process must provide
reasonable alternatives that minimize adverse impacts. The impact analysis must utilize the best scientific
information available, be scrutinized by other agencies and the public, and include direct, indirect, and
cumulative impacts (NPS 2001 a). Overall guidance on defining and evaluating impacts and assessing the
potential for impairment to NPS resources is provided in the sections below.
Two of the alternatives, the Partial-Build A lternative to Bushnell and the Northern Shore Corridor, are
presented throughout the document as baseline routes with segment options and two road type options, as
detailed in Section 2.5. The baseline routes for these alternatives share the same northern alignmentfor
8.0 �ni (12.9 km) related to the Primitive Park Road and 5.8 nzi (9.3 km) related to the Principal Park
Road. The baseline route and all options were afforded the same level of detail during the analysis.
Baseline routes for each road type have been compared to existing conditions (i.e., the No-Action
Alternative). Southern crossings of embaynzents and the terminus location provide options that may be
used in any combination to form alternate routes for the Northern Shore Corridor and the Partial-Build
Alternative to Bushnell, as shown on Figure 2-8. Impact analyses for the options are shown as a
d fference from the associated baseline route. Refer to the previous page for a conzprehensive list of route
and road type combinations.
This EIS documents the analysis of impacts without detailed mitigation, based on information known to date.
Detailed mitigation plans would be developed before impleinentation of a partial-build or build alternative.
A Memorandum of Understanding (MOU) would be developed between the NPS and FHWA to document
the commitment of the two agencies to jointly produce detailed mitigation plans if a partial-build or build
alternative were implemented. Final design and detailed mitigation could reveal site-specific impacts that
are not currently known. Additional NEPA analysis would be required if impacts were found to be greater
than identified in this EIS for any of the partial-build or build alternatives.
4.1.1 Impact Methods/Thresholds
DO-12 requires that an EIS must discuss the impacts of each reasonable alternative under consideration and
must quantify the impacts in terms of their type, context, duration, and intensity. This section defines the
type, context, duration, and intensity for impacts based upon NPS technical guidance and internal
documents.
Methodologies, detailed guidance and regulations, and tailored definitions of impact intensiry are provided
for each resource, or group of resources, in the corresponding section in this chapter. Definitions for the
impact to each resource topic are specific in an individua] EIS.
Type
Impacts are identified as beneficial or adverse. In rare circumstances, impacts are found to be indeterminate
for impacts that were not clearly adverse ar beneficial or which might result in effects of both types.
Clarification of the term "baseline" for this project:
The Partial-Build Alternative to Bushnell and the Northern Shore Corridor include a baseline route, as well as options to that route.
Baseline routes and options are detailed in Section 2.5 and shown on Figure 2-8. Baseline routes have been compared to existing
conditions. Impact analyses for the options are shown as a difference from the associated baseline route.
Environmental Consequences — 4-2
North Shore Road Final Environmental Impact Statement

Context
Effects to a resource are based on a relevant context for that resource, which may be based on geographic
areas, relevant population of the resource, or, in the case of many socioeconomic effects, the perceptions of
affected individuals or groups.
Duration
Effects are short-term, long-term, or permanent. Defining short-term and long-term effects of the
alternatives is complicated in that the construction alternatives require a range of years to complete. For the
purpose of analysis, construction periods were assumed to be 2 years for the Laurel Branch Picnic Area, 5
years for the Partial-Build Alternative to Bushnell, and 15 years for the Northern Shore Corridar. The
definition of permanent is incorporated, in particular, with natural resource impacts, since long-term effects
may occur well before the tim�period of construction is complete.
Intensity
As noted, the intensity of the impacts varies for each resource, but is categorized by NPS guidance as
no/negligible, minor, moderate, or major. The intensity of direct and indirect impacts to the same resource
may vary. Direct impacts are not necessarily more intense than indirect impacts.
4.1.2 Cumulative Impacts
The CEQ regulations to implement the NEPA require assessment of cumulative impacts in the decision-
making process. Cumulative impacts are defined as "impacts on the environment which result from the
incremental impact of the action when added to other past, present, and reasonably foreseeable future actions
regardless of what agency (federal or nonfederal) or person undertakes such other actions" (40 CFR 1508.7).
Cumulative effects were determined for each resource by combining the direct and indirect impacts of the
alternatives being considered with other applicable past, present, and reasonably foreseeable future actions in
the study area. The study area for cumulative impacts was expanded to include the entire GSMNP in order
to adequately address cumulative impacts to Park resources. Cumulative impacts of some resource topics
(e.g., economics) have the potential to extend outside this defined study area boundary and are discussed
from a regional perspective. In addition, some past, current, or future actions outside this study area are
discussed due to their relevance to the project or their regional impact.
Cumulative effects can be distant from the project in time, as well as space; therefore, a time horizon far the
analysis was also considered. The temporal boundary for the analysis was set generally beginning in the late
nineteenth century in order to consider those past actions that played a major role in shaping the study area.
A future temporal boundary of 20 years (2025) was set to encompass planned projects in the study area, as
Clarification of the term "baseline" for this project:
The Partial-Build Alternative to Bushnell and the Northern Shore Corridor include a baseline route, as well as options to that route.
Baseline routes and options are detailed in Section 2.5 and shown on Figure 2-8. Baseline routes have been compared to existing
conditions. Impact analyses for the options are shown as a difference from the associated baseline route.
Environmental Consequences — 4-3
North Shore Road Final Environmental Impact Statement