Introduction :: Presentation Format & SCEA Overview
Module 1 :: How to Determine Which Resources Should be Considered in a SCEA
Module 2 :: How to Establish the SCEA Geographical Boundary
Module 3 :: How to Determine SCEA Time Frames
Module 4 :: How to Develop SCEA Land Use Information
Module 5 :: How to Prepare the Analysis & Reach SCEA Conclusions
Module 6 :: Presentation of SCEA in the Environmental Documentation

Module 5

Slide 1 How to Prepare Analysis and Reach SCEA Conclusions

Slide 2 Overview

Introduction

• Levels of SCEA
• Data Collection
• Regulations/Laws
• Map Environmental Resources and Land Use (Module 4)
• Identify Methodologies/Conduct Analysis
• How to Reach SCEA Conclusions

Slide 3 Introduction

• The analysis phase begins following SHAs request for concurrence on Alternatives Retained for Detailed Study.
• Varying levels of analysis (detail) may be used for different types of projects.
• Analysis results may be quantitative and/or qualitative.
• It is important to consider regulatory programs in the analysis.
• The SCEA results for Alternatives Retained for Detailed Study are included in the draft and final environmental document.

Slide 4 Introduction (continued)

SCEA DONT
Do not develop predictive models to fill in data gaps. Instead, use existing readily available data.

Slide 5 Introduction (continued)

Developing SHA's SCEA Consultant Team

• It is recommended that the consultant responsible for conducting direct impact analyses also conduct the SCEA to ensure compatibility of findings for direct, secondary and cumulative impacts.

(Particularly important for SocioEconomic Resources).

• If different natural environmental, cultural and socioeconomic consultants are used, it is important that land use data layers be transmitted by the socioeconomic consultant to the other consultants for analysis consistency.

Slide 6 Introduction (continued)

Developing SHA's SCEA Consultant Team (continued)

• Conduct an early team coordination meeting if multiple consultants are being used to conduct the SCEA . This will avoid duplication of the work effort and help ensure consistency.
• In situations where there are multiple consultants, the consultant should be clear in which past, present and future land use scenarios to analyze.

Slide 7 Introduction (continued)

• Refinement of SCEA Boundaries
  • Prior to conducting the SCEA technical analysis, it may be necessary to adjust the SCEA geographical boundary based upon agency coordination and/or new information learned collecting land use information.
  • Any adjustments to the SCEA geographic boundary should be completed prior to undertaking any of the analytical methodologies proposed to assess impacts within the SCEA boundary.

Slide 8 Levels of SCEA

The level of SCEA analysis should be tailored to the project type. The following factors are considered in determining the level of analysis:

Availability of Data

• Limit quantitative analysis to resources having readily available quantitative data.
• Conduct qualitative analysis for resources lacking readily available quantitative data.
• Document the rationale for the level of analysis conducted.

Slide 9 Levels of SCEA (continued)

• Presence of Direct or Secondary Impacts
  • If project alternatives do not result in direct or secondary impacts on a resource, no further analysis is necessary although documentation must occur.
• Resources within the SCEA Boundary
  • If secondary or cumulative effects for a resource are not relevant to decisions about the proposed action, it is not necessary to perform SCEA for that resource (e.g. soils and geology).

Slide 10 Data Collection

• Collect Appropriate Data

Slide 11 Regulations & Laws

• Regulatory Programs
  • Certain regulatory programs, (i.e., wetlands and public parklands) essentially provide a degree of protection from direct impacts to applicable resources due to the fact that they have teeth and contain mitigation requirements. This is especially important when conducting trends analysis. Predicting a future condition based on a past trend should factor in how recent laws and regulations will alter the trend of impacts to a particular resource. These programs should be considered in the analysis portion of the SCEA .

Slide 12 Regulations & Laws

*Note that Section 4(f) only applies to federally funded transportation projects

Slide 13 Regulations & Laws (continued)

Slide 14 Map Environmental Resources & Land Uses

• Mapping Resources and Land Uses
  • Mapping environmental resources and land uses within the SCEA boundary provides a base from which many of the analytical methodologies can be performed. As highlighted in Module 4, land use mapping should be prepared for past, present and future time frames. This step must be conducted prior to performing the analyses.

Slide 15 Identify Methodologies & Conduct Analysis

• Four basic SCEA methodologies:
  • trends analysis
  • overlay analysis
  • matrices
  • interviews

Slide 16 Identify Methodologies & Conduct Analysis (continued)

• Integrating different SCEA methodologies for different resources can be used within a SCEA geographical boundary. For example:
  • Trends (qualitative analysis) for wetland losses in a watershed or subwatershed basin can be applied to the SCEA boundary to assess past, and possibly future, impacts to wetlands.
  • Overlays (quantitative analysis) of existing land use/land cover maps can be combined with future land use maps to assess future forest impacts. Note that it is possible to perform qualitative and quantitative analysis on the same resource.
• These methodologies can be used together to assess cumulative effects to a single resource. For example:
  • For example, quantitative GIS and qualitative trend results from different years can be compared to identify past, present, and future resource loss trends.

Slide 17 Identify Methodologies & Conduct Analysis (continued)

Rationale for determining SCEA Methdologies

The methodologies to use for a particular resource should be based on:

• availability of data (use existing, readily available data).
• appropriateness of the data to the SCEA study area. Document what scale or geographical unit is available for each data source (i.e., state level, county level, census tract level, etc.)
• ease of manipulating mapped data (overlays).
• past or future impacts (overlays often cannot be used to assess past impacts because mapping of past resources may not be available).
• impact of regulatory programs (especially regarding future impacts).

Slide 18 Identify Methodologies & Conduct Analysis (continued)

Trends Analysis

• Trends analysis is the comparison of historic data to determine the historic loss and/or projected future resource impacts.
• Reports and studies gathered from various sources may have important information on past effects to resources within the SCEA boundary. Note: Care must be taken in application of regional/statewide trends data to a smaller SCEA boundary.

Slide 19 Trends Analysis Process

SCEA Trends Analysis Process

Slide 20 Identify Methodologies & Conduct Analysis (continued)

Overlay Analysis

• Quantitative or qualitative analysis which entails overlaying present and future land use maps over existing resources to determine present and future impacts. Can be used to determine past impacts, provided past resource mapping is available.
• Overlays can be used to develop trends, which, in turn, can be used to project likely future effects. Remember to consider regulatory programs in projecting future impacts.
• Sources of mapped data for determining past resource impacts include NWI/DNR wetlands mapping (wetlands), and aerial photography (forests, RTE species habitat, and active farmland).

Slide 21 Overlay Analysis

• Overlay your future land use map upon an existing resource such as wetlands, floodplains, farmlands, woodlands and cultural resources. Identify where there is overlap between the resource and the future land use. The overlap between the resource and the future land use is your total impacted area.

Slide 22 Identify Methodologies & Conduct Analysis (continued)

See diagram for the Sample Overlay Analysis Process

Slide 23 Identify Methodologies & Conduct Analysis (continued)

Matrices Analysis

• Matrices alone cannot quantify effects, but they are a useful means of presenting and manipulating quantitative results of trends analysis or overlay process.
• Matrices can be used to show/illustrate trends of impacts to resources. For example, wetland impacts can be shown for pre and postregulation time frames to highlight the effects of regulatory programs.

Slide 24 Identify Methodologies & Conduct Analysis (continued)

Interviews

• Expert interviews are most useful where "hard" data is not readily available and may potentially be the most accurate and efficient method for assessing impacts to certain resources. Interviews can also be used to gather background data in the SCEA boundary.

Slide 25 Identify Methodologies & Conduct Analysis (continued)

Interviews (continued)

Slide 26 How to reach conclusions

The SCEA should "count what counts." The SCEA "should not produce superficial analysis of a long laundry list of issues that have little relevance to the effects of the proposed action on the eventual decisions" (CEQ's Considering Cumulative Effects under the National Environmental Policy Act.)

Slide 27 How to reach conclusions (continued)

SCEA DO
Be sure to document all secondary and cumulative effects. Concluding that there are secondary and cumulative effects is part of the overall SCEA process, so be sure to document when they occur. Keep the purpose of identifying and documenting, even if qualitatively, any of these effects at the forefront of your SCEA process.

Slide 28 How to reach conclusions (continued)

Factors to consider

• Draw on experience of project team members to reach SCEA conclusions.
• Document when there is not sufficient data to analyze effects on a particular resource.
• Do not arbitrarily present data if no conclusions can be drawn.
• Use tables (matrices) to help you interpret data.

Slide 29 How to reach conclusions (continued)

Additional Factors to Consider

• Existing and proposed regulatory controls and how these controls will affect past, present and future impacts to resources.
• Local, county and state planning initiatives. (County Master Plans/Zoning)
• Local preservation programs in place or proposed. (farmland preservation, open space preservation, etc.)
• Future private development proposals and associated land use changes.

Slide 30 How to reach conclusions (continued)

Potential SHA SCEA Mitigation

If there are secondary and cumulative effects, it is important to balance impacts to resources with mitigation efforts.

Slide 31 Potential SHA SCEA Mitigation

• Identification/development of potential mitigation measures for secondary/cumulative effects will result from consultation with appropriate resource agencies and local governments. When mitigation for a resource is warranted, the measures listed below are example of resource mitigation measures that may be considered.
  • Work with local/county government or resource agencies to develop/implement resource preservation plans.
  • Implement access controls that may minimize resource impacts

Exercise 1

Slide 32 Analysis Methodology used in MD 5 Transportation Improvement Project

Note: Interviews are generally used as a last resort

Slide 33 MD 5 Analysis Methodologies

Integrating Trends & Overlay Analyses

Trends analysis and overlays can be used together to assess past and future effects to the same resource. For the MD 5 project, trends were both extracted from existing published trends data and developed through overlay analysis of data sources.

Past

• Past wetland impacts (1972 to present) were assessed by review of statewide trends for the period of 1955 to 1978 as extracted from a USFWS publication.

Present

• Trends for 19811993 were developed by use of GIS (overlay) analysis.

Future

• Projection of past trends into the future with additional consideration of regulatory programs. Had a proper future land use scenario been developed, present wetlands could have been overlaid onto the future land use scenario to develop a conservative estimate of wetlands potentially impacted.

MD 5 Land Use Note: Please refer to the MD 5 example in Module 4.

Slide 34 MD 5 SCEA Analysis Methodologies (continued)

Description of Overlay Analysis

• Past Impacts to Wetlands: Comparison of 1981 NWI mapping with 1993 DNR mapping.
• Past Impacts to Forests: Comparison of 1973 and 1994 Land Use/Land Cover (LU/LC) maps from Maryland Office of Planning (MOP).
• Future Impacts to Forests: Comparison of 1994 Forests per LU/LC maps with proposed development.
• Past and Future Impacts to Active Farmlands: same as per Forests.
• Future Impacts to Cultural Resources: Comparison of NRHP and Maryland Inventory of Historic Places site maps with proposed development (standing structures) and archeological site grid cells with proposed development (archeological resources).

MD 5 Land Use Note: Please refer to the MD 5 example in Module 4.

Slide 35 MD 5 SCEA Methodologies (continued)

Wetlands Integrating Overlay, Trends, & Matrix Analysis

MD 5 Land Use Note: Please refer to the MD 5 example in Module 4.

Slide 36 MD 5 SCEA Methodologies (continued)

See diagram for the Wetlands Possible Analysis Methodology following SHA SCEA Guidelines

Slide 37 MD 5 SCEA Analysis Wetlands

Slide 38 MD 5 SCEA Methodologies (continued)

Historic Properties Overlay Analysis

MD 5 Land Use Note: Please refer to the MD 5 example in Module 4.

Slide 39 MD 5 SCEA Methodologies (continued)

See diagram for the Historic Properties Possible Analysis Methodology following SHA SCEA Guidelines

Slide 40 MD 5 Transportation Improvement Project

See map for the National Register of Historic Places & Maryland Inventory of Historic Places

Slide 41 MD 5 Transportation Improvement Project (continued)

See map for the National Register of Historic Places & Maryland Inventory of Historic Places shown with Proposed Development

MD 5 Land Use Note: Please refer to the MD 5 example in Module 4.

Slide 42 MD 5 Transportation Improvement Project (continued)

National Register of Historic Places and Maryland Inventory of Historic Properties Summary of Secondary and Cumulative Impacts

* Historic Properties within the direct impacts area of the MD 5 project

Slide 43 MD 5 Transporation Improvement Project SCEA Conclusions

Slide 44 MD 5 Transporation Improvement Project SCEA Conclusions (continued)

Exercise 2 | Back to top

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Last modified: Friday September 15, 2000.