Prototype Airport Sustainability Rating System—Characteristics, Viability, and Implementation Options (2014)

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32 4.1 Background Although many efforts have been made to define sustainability and to identify airport sustain- ability practices, no broad, industry-adopted system exists to rate airport sustainability perfor- mance. The ACRP Project 02-28 research team developed a Prototype Airport Sustainability Rating System (Prototype Rating System) that incorporates both stakeholder and project panel feedback. The research team developed the Prototype Airport Sustainability Rating System (Prototype Rating System) to adhere to design specifications identified through the Phase I stakeholder outreach (see Chapter 3). The research team then solicited feedback on the Prototype Rating System from the project panel and conducted a second phase of stakeholder outreach to obtain input on design and content before finalizing the Prototype Rating System. The Prototype Rating System described in this chapter provides a proof of concept that the airport community can use to assess the viability of an airport sustainability rating system and to determine whether to move forward with the development of a Draft Airport Sustainability Rating System. Such a rating system would help airports evaluate continued sustainability per- formance; set sustainability goals, objectives, and targets; improve internal and external relations; increase their competitive advantage; and help justify sustainability management. The Prototype Rating System is designed to allow, initially, individual airports to assess and track their sustain- ability performance internally; however, if desired by the airport community, the framework could also support ratings and comparisons between airports in the future. Finalization of the Draft Airport Sustainability Rating System is beyond the scope of the research work plan for ACRP Project 02-28. Design Specifications and Structural Components To identify stakeholder needs, the research team conducted an extensive survey of airport stakeholders and held formal interviews and informal discussions. As discussed in Chapter 3 of this report, stakeholder input in Phases I and II yielded some general consensus and some lack of agreement across key areas; however, general support for a rating system was apparent. Based on stakeholder input and the research team’s collective expertise, the primary design specifications for the Prototype Rating System were identified. The Prototype Rating System would 1. Incorporate elements of existing rating systems to the extent possible. 2. Include a points-based scoring and rating framework. 3. Adhere to the EONS sustainability framework. 4. Recognize airport-wide sustainability performance (as opposed to individual focus on airport projects). 5. Emphasize flexibility to accommodate all airport types. C H A P T E R 4 Development of Prototype Rating System

Development of Prototype Rating System 33 The Prototype Rating System reflects the research team’s effort to respond to and incorporate the design specifications: The system’s key structural components were developed to meet design specifications. Additionally, features of the Prototype Rating System and its scoring framework were designed to address the final design specification—flexibility. Several key structural components were developed specifically to meet, and cut across, the first four design specifications. These structural components are defined below and described in detail in Section 4.3 of this report. • Sustainability Activities. High-level undertakings that have a strong potential to improve the sustainability of an airport. • Sustainability Categories. Broad organizational levels that group sustainability activities of a similar sustainability theme, such as natural resource protection, water and waste management, or economic performance. • Performance Metrics. Indicators of performance within a sustainability activity that allow an airport to measure and track performance over time. • Performance Actions. Efforts taken to improve sustainability that, when evaluated alongside other performance actions, serve as good indicators of sustainability performance. • EONS Icons. Symbols that identify which aspects of the EONS framework apply to a sustain- ability category, accompanied by a discussion section for each aspect. • Innovation. The opportunity for additional points from exemplary performance. The fifth design specification—flexibility—influenced features of the Prototype Rating System and its scoring framework. This flexibility allows airports to rate their sustainability performance in a numerical manner (based on a performance metric) or on the status of performance actions if no metrics are appropriate. As a result, flexibility is interwoven into several Prototype Rating System features, such as: • Performance metrics, which are designed to be overarching indicators of sustainability. Using metrics to rank an airport’s performance promotes actual progress toward sustainability by focusing on outcomes. This is in contrast to some existing rating systems that only assess progress by tallying up the implementation of various sustainability projects as a proxy for sustain- ability performance improvement. The performance metric-based approach offers flexibility by allowing an airport to choose its own path toward improved sustainability performance rather than prescribing a set of specific actions that must be completed. In situations where metric-based performance evaluation is not available or practical, consideration is given to sustainability performance actions. • The scoring framework, which allows airports to evaluate performance—and determine a rating—at the category level. Use of the scoring framework provides airports with the flexibility to use the rating system to evaluate performance for categories that are priorities for the airport leadership and that are appropriate given the scope of their sustainability efforts. Section 4.2 of this chapter describes the research approach used to develop the Prototype Rating System and scoring framework as well as the overall system design. Section 4.3 provides a detailed description of the Prototype Rating System and addresses the specific methodology used to develop each of the structural design components of the rating system. Section 4.4 presents the rating system’s purpose, potential users, and management options, coupled with discussions of the certification and verification options. Section 4.5 lays out potential next steps for rating system development, recognizing that the airport community will need to determine if it is appropriate to move forward with developing a full rating system to be tested by the airport industry.

34 Prototype Airport Sustainability Rating System—Characteristics, Viability, and Implementation Options 4.2 Research Approach This section presents the research approach used to prepare the Prototype Rating System. Feedback from the Phase I stakeholder outreach indicated that the stakeholders felt the rating system should be informed by existing rating systems. Therefore, the research approach began with a review of existing rating systems to identify elements—such as categories, activities, and metrics—that should be considered for the Prototype Rating System. Figure 4-1 presents the approach used to review existing rating systems and to identify elements that should be considered for the Prototype Rating System. As shown in Figure 4-1, the research team reviewed existing sustainability rating systems and generated lists of structural elements, such as categories, activities, and metrics. The research team also made note of other features used by these rating systems. Sustainability subject matter experts identified and filled any gaps in these lists. The research team then evaluated each ele- ment using evaluation criteria that closely mirrored the design specifications (e.g., flexibility and ability to recognize performance airport-wide). The evaluation criteria are discussed in more detail in Section 4.3. Finally, elements were adapted as necessary to cater to the structural compo- nents of the Prototype Rating System (such as to develop sustainability categories, sustainability activities, performance metrics, and performance actions) and to inform the scoring framework (discussed in a subsection titled “Establishing a Rating” in Section 4.3). Drawing from Existing Rating Systems to Develop Categories, Activities, Metrics and Actions More than 20 existing rating systems were assessed. A summary of the research findings is given in Chapter 2 of this report. Of the systems examined, the following seven sustainability reporting or rating systems were selected for detailed review because they are prominent in the sustainability field, they address airport-relevant activities, and they cover sufficient breadth and depth of technical content: • Global Reporting Initiative (GRI): Sustainability Reporting Guidelines 3.1 and the AOSS (Version 3.1/AOSS Final Version). • LEED: 2009 Guidelines for Existing Buildings and Operations Maintenance. • LAWA: Sustainable Airport Planning, Design and Construction Guidelines, Version 5.0 (LSAG). • Sustainable Design Manual, 2003; Sustainable Airport Manual 2009–2011 (Current Version 2.1, CDA). • PANYNJ: Sustainable Infrastructure Guidelines (Part 2). • Sustainability Tracking Assessment & Rating System (STARS) (Version 1.2 Technical Manual). • Institute for Sustainable Infrastructure (ISI): “A Rating system for Sustainable Infrastructure.” Envision™ Sustainability Rating System (Version 2.0). Four of the systems are specifically focused on airports—GRI, LSAG, SAM, and PANYNJ— the others have cross-sector applicability with relevance for airports. (Note: Green Globes is an assessment and rating system for existing building sustainability that grew in prominence Figure 4-1. Research approach to develop Prototype Rating System components. Source: ICF, 2013

Development of Prototype Rating System 35 following this phase of the research. The federal government now recognizes Green Globes as an accepted system for evaluating sustainable building performance.) The research team utilized a spreadsheet-based organizational matrix to compile, sort, and filter categories, activities, metrics, and over 800 activities from these seven rating systems (Figure 4-2). The research team used the matrix to organize, associate, consolidate, and evaluate these elements to select suitable sustainability categories, sustainability activities, performance metrics, and actions for the Prototype Rating System. Draft and Final Prototype Rating System Development After reviewing existing rating systems to evaluate their content and features and developing a list of the content and features that aligned with the design specifications for the draft Prototype Rating System, the research team developed a conceptual framework and materials that illus- trated the Prototype Rating System, including example pages for a Rating System User Guide and a preliminary list of sustainability categories and activities. After obtaining review comments from the ACRP project panel on the draft Prototype Rating System, the research team conducted a second stakeholder outreach effort to obtain their feedback on the Prototype Rating System. As described in Chapter 3, the panel discussion and Phase II stakeholder outreach effort led to several revisions, ultimately resulting in the final Proto type Rating System that is included in this report. 4.3 Proposed Prototype Rating System Design This section provides an overview of the structure of the Prototype Rating System and the proposed framework for establishing a rating. Source: ICF, 2013 Figure 4.2. Existing rating system evaluation matrix (screenshot).

36 Prototype Airport Sustainability Rating System—Characteristics, Viability, and Implementation Options Preliminary User Guide The Prototype Rating System comes in the form of a User Guide that includes all of the necessary background and implementation information required for an airport user to pilot, and eventually adopt, the rating system. For ACRP Project 02-28, the research team prepared an annotated outline of the Preliminary User Guide that includes the following key sections: • Table of Contents. • Introduction. This section describes the purpose, development and benefits of a sustainability rating system. • Rating System Structure. This section defines and explains the structural components of the rating system. • Rating System Use. This section explores the use of the rating system through the activities, scoring mechanism, overall rating, and certification and verification. • Sustainability Activities. This section makes up the largest section of the User Guide. It defines each of the 50 activities and describes how to achieve performance (and points) under each activity through performance metrics. • Appendices. The appendices present additional useful information. The complete Preliminary User Guide Annotated Outline appears in Appendix C of this report. The Prototype Rating System’s structural components were developed through the research approach (see Section 4.2). In response to the design specifications developed through stakeholder outreach, these structural components were refined based on discussions with the ACRP panel and a stakeholder review of the Prototype Rating System. The following structural components of the rating system are described in detail in this section, along with examples and a description of the methodology used to develop them: • Sustainability categories. • Sustainability activities. • Performance metrics. • Performance actions. • EONS icons. • Innovation. Figure 4-3 shows a sample User Guide excerpt for the waste diversion sustainability activity. Figure 4-4 provides a full-size view of the first page of the excerpt. The User Guide excerpt pro- vides an example of the structure of a sustainability activity and the type of content that will be presented in the Rating System User Guide. The research team prepared five User Guide excerpts to illustrate the Prototype Rating System (see Appendix D). Snapshots of User Guide excerpts are presented throughout this section to illustrate the structure of a sustainability activity as well as to show the type of content that is presented in the Rating System User Guide. The excerpts highlight how the structural components and other features are incorporated throughout the Prototype Rating System. Identifying Existing Rating System Elements to Inform Prototype Rating System Structural Components The research team assessed the applicability of existing rating system elements for use in the Prototype Rating System using the evaluation criteria. Evaluation criteria that stemmed from the stakeholder outreach process and are mostly objective were categorized as primary; those that are mostly subjective were categorized as secondary. • Primary evaluation criteria: – Support airport-wide applicability across infrastructure, operations, and management. – Accommodate airports of varying type, size, and location.

Development of Prototype Rating System 37 Figure 4-3. Example User Guide excerpt. Source ICF, 2013 Note: See Appendix D for all five User Guide excerpts.

38 Prototype Airport Sustainability Rating System—Characteristics, Viability, and Implementation Options – Consider performance that would be within the direct control of the airport. – Provide flexibility so that airports can choose how best to pursue sustainability. – Support existing airport activities. – Recognize performance to date. – Facilitate documentation. • Secondary evaluation criteria: – Are brand-neutral and technology-agnostic – Provide a broad indication of performance across EONS – Clearly link sustainability activities, performance metrics, and overall sustainability performance – Support reasonable data management expectations – Require a reasonable level of effort to implement The research team used the primary and secondary evaluation criteria to identify existing rating system elements that could inform the Prototype Rating System’s categories, activities, metrics, and actions. Structural Component 1: Sustainability Categories Sustainability categories are broad organizational levels that group sustainability activities of a similar theme. The categories highlight the high-level elements of performance and bind the Source: ICF, 2013 Figure 4-4. Structure of a sustainability activity excerpt from the Proposed Rating System User Guide.

Development of Prototype Rating System 39 broad spectrum of activities into manageable groups with similar objectives so an airport can focus its efforts. Sustainability categories are not, however, intended to overlook the important synergistic nature of sustainability or disaggregate sustainability into independent realms. Rooted in the EONS framework, the categories work to link sustainability across all aspects of an airport. The Prototype Rating System includes eight sustainability categories based on research of existing rating systems and the elements of sustainability applicable to an airport (Table 4-1). Methodology. The research team developed sustainability categories by reviewing existing reporting and rating systems, identifying and combining like categories, and identifying gaps to generate a preliminary list. The research team then evaluated and refined the list based on the evaluation criteria and their relevance to airport activities. To identify and incorporate unique topics of sustainability currently covered in existing rating systems, all categories used in existing systems were combined into a single list. The number of categories ranged from 6 categories in LEED to 35 categories in the GRI Sustainability Reporting Guidelines. The resulting list of 96 categories was organized based on similar sustainability topics, such as energy, water, labor, and indoor environments. Broader categories that included multiple sustainability topics—such as sustainable sites in LEED, which addresses design and construction, alternative transportation, stormwater, and other topics—were disaggregated. Redundant topics were condensed, and unique topics were added if not already reflected in the list. Figure 4-5 illustrates how the research team tallied similar categories across all rating systems to find commonalities. The research team reviewed the category list for gaps, applying subject matter expertise to identify topics not covered in the list and to identify similar categories that could be combined into logical groupings. The research team cross-referenced the categories against the evaluation criteria to ensure that each category demonstrated applicability across airport functions, allowed flexibility for different airport types, and could contain a broad range of activities that would allow an airport to pursue multiple options and pick the ones that best fit their unique situation while progressing toward the goal of improved sustainability. The list was also evaluated for its comprehensiveness across the spectrum of sustainability and across the EONS framework. This effort produced a draft list of 13 sustainability categories. Based on stakeholder and panel member recommendations, the draft list was further consolidated to 8 categories to simplify integration into the SAGA database. Stakeholders had suggested that a more manageable category set would support alignment with and ease integration into the SAGA database and increase the likelihood of adoption of the rating system. Structural Component 2: Sustainability Activities Ultimately, the goal of the airport sustainability rating system is to recognize and encourage airport management to conduct activities in a sustainable manner on a daily basis. For example, airport staff use alternative fuels in vehicles and equipment; they divert waste from landfills by Sustainability Categories Energy & Climate Engagement & Leadership Transportation Water & Waste Economic Performance Natural Resources Design & Materials Human Well-Being Source: ICF, 2013 Table 4-1. Prototype sustainability categories.

40 Prototype Airport Sustainability Rating System—Characteristics, Viability, and Implementation Options providing recycling bins; and they encourage employee development by offering staff trainings. The Prototype Rating System recognizes and represents each of these activities as a sustainability activity because they support the overall sustainability of the airport. Sustainability activities are high-level undertakings that have a strong potential to improve the sustainability performance of an airport. A design specification identified through stakeholder outreach was the desire to rank an airport’s performance, rather than tally up the completion of various sustainability projects. As such, sustainability activities, and their associated performance metrics and performance actions, promote actual progress toward sustainability by focusing on the outcome rather than the process or projects completed. This facilitates flexibility, allowing an airport to choose how best to achieve a high level of sustainability performance. Across the 8 sustainability categories, 50 distinct sustainability activities provide the frame- work of the Prototype Rating System (Figure 4-6). The research team sourced most of the sus- tainability activities used in the Prototype Rating System from existing rating systems, taking airport applicability and the evaluation criteria into account. Figure 4-7 illustrates the number of sustainability activities that were informed by each of the existing rating systems. In many cases, an activity was informed by more than one existing rating system. The STARS rating system, in particular, contributed to the development of a majority of the prototype sustainability activities, because STARS focuses heavily on overall performance through metrics. These metrics helped to inform and often transferred well into the Prototype Rating System. Figure 4-5. Frequency of similar sustainability categories across existing rating systems. Fre Source: ICF, 2013

Development of Prototype Rating System 41 Each sustainability category may contain few or many sustainability activities, depending on how well the activities cover the breadth of performance under each sustainability category. Within the Water & Waste sustainability category, for example, the only water-related sustainability activity is Potable Water Conservation, because it captures the high-level sustainability objective, which is to reduce the amount of potable water consumed at an airport. The human well-being category, on the other hand, includes multiple activities, such as employee development, labor relations, and diversity and equal opportunity, because no one activity can capture all of the most important elements of human resources and employee well-being. Methodology. The research team reviewed existing rating systems and assessed how they address each sustainability category. For any given category, such as Energy & Climate, each category, activity, project, or metric included in the existing rating systems was compiled in a list for review. The review revealed that each rating system evaluated performance and awarded points differently. For example, the CDA Sustainable Airport Manual (CDA SAM) awards points for individual actions or processes. Alternatively, STARS focus on outcomes and often Figure 4-6. Prototype sustainability categories (8 categories) and sustainability activities (50 activities). Source: ICF, 2013

42 Prototype Airport Sustainability Rating System—Characteristics, Viability, and Implementation Options uses quantifiable performance metrics to award points. The information from existing rating systems was sorted on whether it reflected individual actions or quantifiable metrics. This step helped the research team develop the performance metrics and actions discussed in Structural Component 3: Performance Metrics and Actions. This work occurred jointly with the choice of sustainability activities because knowing how performance would be evaluated (i.e., using metrics and actions) helped to delineate each activity. The diverse collection of metrics from existing rating systems were analyzed to determine their ultimate sustainability objective (e.g., “to reduce energy use,” “to reduce greenhouse gas emissions,” or “to improve labor relations”). Objectives were compiled, organized by topic, and evaluated using the evaluation criteria to identify and select the prototype sustainability activities. Sustainability activities that target a broader range of sustainability considerations, address sustainability airport-wide, and promote flexible strategies were preferred over those that prescribe a specific avenue to success, because they offer more flexibility and are likely to accommodate evolving techniques and technologies. For example, an activity common to several existing rating systems is increasing the use of energy-efficient lighting. While increasing energy-efficient lighting is important, it represents a narrower, prescriptive activity that supports the broader objective of reducing building energy use. The research team grouped similar, narrow activities to prepare a consolidated set of sustainability activities. This approach will increase flexibility by allowing air- ports to choose sustainability strategies that are tailored to their organizations, while preserving a high-level objective that they can use to evaluate performance. This approach also recognizes that a wealth of guidance material is available to airports to help them execute individual sustain- ability projects. It also recognizes that sustainability techniques and technologies are constantly Source: ICF, 2013 GRI: Global Reporting Initiative STARS: Sustainability Tracking, Assessment & Rating System ISI: Institute for Sustainable Infrastructure Envision™ PANYNJ: Port Authority of New York and New Jersey LEED: Leadership in Energy and Environmental Design CDA SAM: Chicago Department of Aviation Sustainable Design Manual (2003)/ Sustainable Airport Manual (2009)—2011, Version 2.1 Construction Guidelines Sustainable Airport Manual (2009)—2011, Version 2.1 LSAG: Los Angeles World Airports: Sustainable Airport Planning, Design and Notes: Each of the 50 sustainability activities evaluated can be informed by more than one rating system. “Research Team” indicates sustainability activities that were informed by the research team’s collective expertise to supplement existing rating systems. 6 9 16 17 18 19 22 30 Research Team LEED PANYNJ CDA SAM ISI LSAG GRI STARS 0 10 20 30 40 Figure 4-7. Number of sustainability activities informed by each existing rating system.

Development of Prototype Rating System 43 advancing; rather than replicate guidance or endorse technologies, the Prototype Rating System establishes a high-level objective to serve as a goal for sustainability performance. This process was repeated for each of the eight sustainability categories, whereby metrics and projects were extracted from the existing rating systems and assessed for their ultimate sustainability objectives to develop sustainability activities. Subject matter experts analyzed each category for gaps, ensuring that the breadth of activities covered the scope of that category. The research team prepared an initial set of 47 sustainability activities. Based on stakeholder recommendations and panel concurrence, 3 additional activities were added to prepare a final set of 50 sustainability activities. (The complete set of sustainability activities is listed in Table 4-2, which appears in a later section of this chapter.). Structural Component 3: Performance Metrics and Actions To evaluate, or rate, sustainability performance for each sustainability activity, airports need performance metrics. A performance metric is an indicator of performance within a sustainability activity that allows the airport to measure and track performance over time. The performance metric is a critical component of the Prototype Rating System because it forms the basis of the scoring framework—meeting the design specification that the rating system should allow the airport to rate its performance (see “Establishing a Rating” in this chapter). As with the sustainability activities, performance metrics allow an airport to measure performance without being overly specific about how the airport should operate. This supports a design specification preference toward scoring an airport’s measured performance with respect to a specific activity. A strong metric is clearly linked to performance (i.e., it gets as close as possible to measuring actual progress rather than serving as a proxy). It acknowledges improvement over time, and it aligns with actions airports are likely to measure or already measure. In general, metrics are based on percentages, incorporate normalized intensities, and can involve baseline comparisons. For many, but not all, sustainability activities, performance can be evaluated using a single performance metric. For some activities, however, it is more appropriate to evaluate performance using actions, either because the field is evolving and adequate metrics have not yet been developed or because the activity does not lend itself to measurement. In these cases, performance actions are used to evaluate sustainability. As a result, in the Prototype Rating System, sustainability activities are evaluated using one of two evaluation types: a performance metric (Evaluation Type 1) or a set of performance actions (Evaluation Type 2). Evaluation Type 1: Performance Metric. Sustainability activities are associated with a per- formance metric chosen as the best measure of progress in each category. For example, under the waste diversion sustainability activity, the preferred performance metric is: “Percent of total solid waste diverted from a landfill or incinerator annually.” This metric captures the objective of the sustainability activity, which is to increase the amount of waste diverted from a landfill or incinerator, thereby reducing the environmental impact of disposing of solid waste in landfills or incinerating solid waste. The metric does not prescribe a specific path to performance, which allows airports the flexibility to choose their own strategies. It presents a clear link to performance and sets the stage for comparison among airports (if that option is ultimately pursued) despite differences in size, type, or location. Performance metrics are supported by a set of performance recommendations, which are used for informational purposes and recommended—not required—for an airport to take to improve sustainability performance for that activity. Evaluation Type 2: Performance Actions. Performance actions are efforts taken to improve sustainability that, when evaluated alongside other performance actions, serve as good indicators

44 Prototype Airport Sustainability Rating System—Characteristics, Viability, and Implementation Options of sustainability performance. For each sustainability activity, a set of approximately 10–12 per- formance actions that serve collectively as a good indicator of sustainability performance can be used to evaluate performance. Each set will contain more actions than are required for the highest level of performance. Thus, the set of performance actions would serve as a menu from which airports can choose the most practical options given their situation, granting them flexibility. Additional research is necessary to determine the exact number of performance actions that will be appropriate to gauge performance adequately for each sustainability activity in a complete rating system. Under the climate change adaptation activity, for example, research of existing rating systems and other sources yielded no consistent or industry-accepted measurement or metric of an airport’s ability to respond and adapt to the impacts of climate change. Instead, a set of performance actions were selected that reflect milestones along an adaptive management pathway. For the climate change adaptation activity, a menu of performance actions ranging from preparing vulnerability assessments to hardening structures is therefore used to evaluate performance. Depending on the sustainability activity, the Prototype Rating System applies either a perfor- mance metric (Evaluation Type 1—see Figure 4-8) or a set of performance actions (Evaluation Type 2—see Figure 4-9). Where appropriate, both performance metrics and performance actions will direct the user to existing rating systems for project- or type-specific ratings. For example, one performance metric is “percent of total building space that achieves a recognized sustainable per- formance certification (e.g., LEED, Green Globes).” As discussed in the description of Evaluation Type 1, activities that utilize performance metrics also include a set of suggested actions (called performance recommendations) that are not required to achieve points under the activity but can serve as a starting point for airports to improve performance under the metric. Many airport initiatives and projects can support each sustainability activity. As an example, an airport may have a no-idling policy that is instituted by management, enforced through staff operations, and supported by an infrastructure resource such as a cell phone waiting lot. Collectively, these airport activities contribute to less idling, which reduces the airport’s indirect greenhouse gas emissions (a sustainability activity). Demonstrating that all airport activities contribute to improving sustainability helps to fold sustainability into an airport’s culture. To support an airport-wide focus rather than a focus on the benefits of individual, unconnected projects, perfor- mance actions and performance recommendations are organized under airport infrastructure, operations, or management. Under this organization scheme: • Infrastructure includes all of the structures and assets within the airport’s boundaries, such as terminals, runways, control towers, parking lots, hangars, vehicles, utilities, and so forth. • Operations describes the implementation of management direction and how infrastructure is used to enhance sustainability. • Management describes how an airport is administered at a high level. It directs and connects the sustainability of both infrastructure and operations. As seen in Figure 4-9, grouping the sustainability actions in this manner highlights the impor- tance and necessity of connecting sustainability across the airport, rather than focusing on one Figure 4-8. Example performance metric from User Guide excerpt. Source: ICF, 2013

Development of Prototype Rating System 45 narrow aspect. For example, an airport may wish to reduce airside equipment fuel use under the transportation sustainability category, but may lack the resources or capacity to upgrade infrastructure or equipment in the short term. The airport still has options to improve its perfor- mance from an operational or management perspective, however, such as implementing a no-idling policy, right-sizing equipment per trip, or improving maintenance and repair schedules. Methodology. The approach the research team used to select performance metrics and performance actions is also discussed in the section, “Structural Component 2: Sustainability Activities” because the research was closely linked to developing sustainability activities. Perfor- mance metrics and performance actions from existing rating systems were grouped and com- pared against the evaluation criteria and then selected based on how well they meet the criteria and measure progress given the overall objective of the sustainability activity they supported. Additionally, each performance metric and performance action was assessed for its capacity to promote actions across airport activities (infrastructure, operations, and management), across EONS, and within an airport’s direct control. Performance metrics and actions were chosen that touched on a greater range of these elements and if they were objective and verifiable to support documentation, self-verification, and/or third-party certification. Figure 4-9. Example set of performance actions organized by infrastructure, operations, and management for waste diversion.

46 Prototype Airport Sustainability Rating System—Characteristics, Viability, and Implementation Options The research team also recognized the value of percentages, intensities, and baselines when iden- tifying or adapting performance metrics. The scoring framework (discussed in the section titled “Establishing a Rating”) is based on levels of increasing performance that have been standardized to percentage thresholds (often compared to baseline of performance) rather than absolute values. In this sense, airports of various sizes can be compared based on their own relative percentages, whereas absolute values might favor smaller or larger airports, depending on the metric. For example, an absolute energy use intensity target (e.g., British thermal units (Btu)/square foot) might favor an airport with a smaller square footage, because a larger airport would have to reduce its overall energy use by a much larger amount to meet the same absolute target. In contrast, a percent reduction from a baseline would not favor one size over another. As such, the metric chosen from existing rating systems needed to cater to the percentage threshold structure. In addition, the use of normalized intensities (e.g., percent reduction of building energy use intensity) was often preferable to absolute volumes (e.g., total energy reduction) because the latter does not cater well to changes in operations or infrastructure. Also, normalizing metrics using intensities would support comparison of airports of different types, sizes, and locations should the rating system be adapted to serve that purpose. Finally, a secondary design specification was that the rating system should acknowledge improve- ment over time, as well as give credit for progress already made. The research team addressed this need by incorporating baselines, rather than benchmarks, where appropriate. Baselines are specific to each airport; whether an airport establishes its baseline this year or 10 years ago, any reductions made since the baseline can be claimed as progress. In addition, benchmarks do not adapt easily to the diversity of airport types, sizes, and locations, requiring a longer list of airport-specific bench- marks and leaving little ability to compare performance among airports. Performance metrics and performance actions selected from existing rating systems were modified where appropriate to accommodate the needs of the Prototype Rating System, such as allowing for improvements over time, being intensity-based, and including baseline comparisons. Ultimately, just over half of the sustainability activities identified for the Prototype Rating System use performance metrics; the remaining sustainability activities use performance actions. Additionally, the Prototype Rating System only includes sustainability activities that go beyond regulatory compliance. Compliance is assumed to be a base standard that all airports should achieve, and it is therefore not an indica- tor of sustainability in areas such as water quality, stormwater quality, air quality, occupational health and safety, environmental assessment, and fair labor practices. As part of the evaluation criteria, the research team also considered whether sustainability activities and their related performance metrics and actions took into account and evaluated only performance that was within the control of the airport, while still encouraging improvement in areas outside of the airport. With regard to performance metrics (Evaluation Type 1), the final metrics were designed to capture only performance over which the airport has control. For example, the terminal building energy use activity omits energy consumption and performance of tenants and vendors, as the airport may not have influence over their energy use. The rating system would not penalize the airport in these cases. The research team considered this sphere of control with regard to all activities and metrics. On the other hand, the research team recognized the importance of encouraging airports to engage in sustainability beyond their operational borders and control, where the benefits of sustainability occur outside the footprint of the airport, such as within the community or part- ner organizations. Several sustainability activities that evaluate performance through a menu of performance actions (Evaluation Type 2) include actions that encourage airports to pursue sustainability in areas beyond their direct control, such as with tenants and other airport users. For example, the engagement and leadership category includes several activities that promote airports to engage with airport-related stakeholders, local communities, public groups, tenant, and vendors in environmental sustainability, social, and economic areas. In these instances, airports

Development of Prototype Rating System 47 are evaluated based on the extent to which they engage others outside their control, rather than on quantitative improvements in sustainability that are outside the airport’s areas of control. Table 4-2 presents the final 50 sustainability activities identified for the Prototype Rating System by sustainability category. Performance metrics and indications of performance actions are also provided and the main sources (i.e., existing rating systems) that were referenced to develop the final metric are identified. (continued on next page) Table 4-2. Sustainability activity list, including performance metrics and sources (existing rating systems). Sustainability Activity Performance Metric Sources Energy and Climate (EC) EC 1 Terminal Building Energy Use Percent reduction of building energy use intensity per square foot (Btu/ft2) from a baseline. Building total square feet is derived from gross area, which is the net usable square feet plus structural square feet. (Airports without terminals will still evaluate administrative building energy use intensity.) GRI: Environment Indicator EN5-7 STARS: Operations Credit 7: Building Energy Consumption ISI RA2.1: Reduce Energy Consumption Adapted by ACRP research team EC 2 Overall Airport Energy Use Percent reduction of total airport energy use intensity from a baseline. The energy intensity unit of output metric may be designated from one of the following: number of airport customers/employees, number of aircraft movements, tonnage of cargo handled, or another appropriate metric. GRI: Environment Indicator EN5-7 STARS: Operations Credit 7: Building Energy Consumption ISI RA2.1: Reduce Energy Consumption Adapted by ACRP research team EC 3 Renewable Energy Use Percent of total airport energy consumed annually, including electricity and other fuels derived from renewable sources. GRI: Environment Indicator EN6 STARS: Operations Credit 8: Clean and Renewable Energy ISI RA2.2: Use Renewable Energy PANYNJ: Energy IE-4 Adapted by ACRP research team EC 4 Terminal Building Greenhouse Gas (GHG) Emission Reductions Percent reduction of Scope 1 and Scope 21,2 GHG emission intensity per gross square foot from a baseline. Building total square feet is derived from gross area, which is the net usable square feet plus structural square feet. (Airports without terminals will still evaluate administrative building GHG intensity.) GRI: Environment Indicators EN16-18 STARS: Operations Credit 5: GHG Reductions ISI CR1.1: Reduce Greenhouse Gas Emissions Adapted by ACRP research team EC 5 Overall Airport Greenhouse Gas Emission Reductions Percent reduction of Scope 1 and Scope 2 GHG emission intensity from a baseline. The emission intensity metric may be one of the following: number of airport passengers/employees, number of aircraft movements, tonnage of cargo handled, or another appropriate metric. GRI: Environment Indicators EN16-18 STARS: Operations Credit 5: GHG Reductions ISI CR1.1: Reduce Greenhouse Gas Emissions Adapted by ACRP research team EC 6 Other Indirect Greenhouse Gas Emission Reductions Performance is evaluated and points are awarded based on the number of performance actions pursued that address, for example, preferential procurement policies that consider lifecycle emissions, reduced business travel, waste management improvements, and employee single occupancy vehicle (SOV) commute reduction, among others. GRI: Environment Indicators EN16-18 STARS: Climate Credits PANYNJ: Multiple Credits ACRP Report 11 EC 7 Climate Change Adaptation Performance is evaluated and points are awarded based on the number of performance actions pursued that address, for example, conducting vulnerability assessments, siting plans, hardening and protecting critical infrastructure, and adaptive management procedures. LSAG: Climate Change Adaptation Planning ISI CR2.1: Assess Climate Threat Adapted by ACRP research team • • • • • • • • • • • • • • • • • • • • • • • • • • • • (Text continues on page 53.)

48 Prototype Airport Sustainability Rating System—Characteristics, Viability, and Implementation Options Table 4-2. (Continued). WW 2 Waste Reduction Percent reduction of solid waste production from baseline intensity. The intensity metric may be airport produced ton/cubic yard of waste divided by indoor square footage, number of airport passengers/employees per period, number of aircraft movements per period, tonnage of cargo handled per period, or another appropriate metric. GRI: Environment Indicator EN21 STARS: Operations Credit 17: Waste Reduction Adapted by ACRP research team WW 3 Waste Diversion Percent of total solid waste diverted from a landfill or incinerator annually. Alternative disposal methods include recycling, composting, reusing, refurbishing, selling, and donating. STARS Technical Manual: Operation Credit 18: Waste Diversion ISI RA1.5: Divert Waste from Landfills Supported by CDA SAM: Waste Stream Management & LEED Sustainable Sites Transportation (TR) TR 1 Fleet Vehicle Fuel Economy Percent increase in fuel economy from a baseline, measured as vehicle miles traveled per gallon of fuel consumed. ACRP research team TR 2 Airside Equipment Energy Use Performance is evaluated and points are awarded based on the number of performance actions pursued that address, for example, vehicle idling, high-efficiency equipment procurement, maintenance and repair schedules, and right-sized vehicle planning, among others. ARCP research team GRI: AOSS TR 3 Alternative Vehicle Fuels Percent of total fleet fuel energy purchased annually derived from alternative sources (as a portion of total cost, or energy content of fuel/electricity purchased). Energy content can be converted to British thermal units (Btu). Purchased fuel/electricity is assumed to be consumed in that same year. Electric vehicle charging requires dedicated metering. LSAG: Support Alternative Fuel Vehicles CDA SAM: Alternative Transportation STARS: Operations Credit 18: Campus Fleet Adapted by ACRP research team TR 4 Alternative Passenger Transportation Performance is evaluated and points are awarded based on the number of performance actions pursued that address, for example, parking incentives and infrastructure for alternative, HOV, low-emitting, and pedestrian forms of passenger transportation. LSAG: Support Alternative Fuel Vehicles CDA SAM: Alternative Transportation STARS: Transportation Credits ISI QL2.5: Alternative Transportation PANYNJ: Site Section IS-16-21 TR 5 Alternative Employee Commute Percent of employee alternative commutes versus total commutes by all full- and part-time employees. STARS: Operations Credit 16: Employee Commute Modal Split LEED: Existing Building O&M SSc4: Alternative Commuting Transportation • • • • • • • • • • • • • • • • • • • • Sustainability Activity Performance Metric Sources Natural Resources (NR) NR 1 Landscape & Grounds Performance is evaluated and points are awarded based on the number of performance actions pursued that address, for example, improved xeriscaping and vegetation selection, runoff and soil assessments, erosion control planning, on-site composting systems, rainwater harvesting, and irrigation efficiency measures, among others. • LSAG: Landscape Design, Stormwater Management • LEED: Sustainable Sites • CDA SAM: Landscape, Erosion Control • STARS: Water Credits • ISI NW1.6, NW2.2, NW3.2 • PANYNJ: Site Section Water and Waste (WW) WW 1 Potable Water Conservation Percent reduction of potable water use intensity from a baseline. The intensity indicator can reflect overall potable water consumption divided by indoor square footage, number of airport customers/employees per period, number of aircraft movements per period, or another appropriate metric such as tonnage of cargo handled. The airport should determine which intensity metric best reflects potable water used based on its unique operations. GRI: Environment Indicators EN8-10 CDA SAM: Water Use Reduction STARS: Operations Credit 22: Water Consumption ISI RA3.2: Reduce Potable Water Consumption Adapted by ACRP research team • • • • •

Development of Prototype Rating System 49 Table 4-2. (Continued). Sustainability Activity Performance Metric Sources NR 4 Airside Stormwater Quality Performance is evaluated and points are awarded based on the number of performance actions pursued that address, for example, deicing fluid management, designated deicing and vehicle washing areas, water filtration systems, biological treatment, and runoff capture, among others beyond compliance standards. • CDA SAM: Stormwater Design, Stormwater Management • LSAG: Stormwater Management NR 5 Wildlife Hazard Management A percent decrease in total annual number of wildlife strikes per 10,000 aircraft movements relative to a baseline. • GRI: AOSS NR 6 Heat Island Reduction Performance is evaluated and points are awarded based on the number of performance actions pursued that address, for example, low solar reflectance and high albedo building and paving materials, increased vegetation and green roofing, and increased shade and covering. • LSAG: Heat Island Reduction • LEED: Heat Island Reduction • CDA SAM: Landscape and Exterior Design to Reduce Heat Islands • ISI CR2.5: Manage Heat Island Effects • PANYNJ: Site IS-14 Economic Performance (EP) EP 1 Socially Responsible Financial Investment Percent of total significant investment agreements and contracts that include social and environmental stipulations or that have undergone social and environmental screening. • GRI – Airport Supplement • STARS: Investment • Adapted by ACRP research team EP 2 Airport Financial Viability Operating cost vs. operational performance unit. For commercial airports performance is measured per enplanement. Cargo airports measure costs per cargo ton; and general aviation airports track change in operating cost over performance period. This metric excludes non-operating costs such as debt service and depreciation. • FAA Form 127 • ACRP Report 19A: Airport Key Performance Indicators: Financial EP 3 Risk Management Performance is evaluated and points are awarded based on the number of performance actions pursued that address, for example, risk assessment procedures and risk management planning for a variety of airport projects and operations, transactional safeguards to minimize corruption, crisis preparedness and response planning, and enhanced risk training, among others. • GRI – 1.2 • ISI: Climate & Risk • ACRP research team EP 4 Regional Economic Contributions Performance is evaluated and points are awarded based on the number of performance actions pursued that address, for example, assessing the impact of sustainability initiatives; community needs assessment; low- income areas, evaluating benefits and impacts on the region; local jobs and recruiting, payroll disclosure, and economic activity. • GRI • ACRP research team NR 2 Wildlife and Habitat Protection Performance is evaluated and points are awarded based on the number of performance actions pursued that address, for example, identifying, monitoring, restoring, and protecting ecologically sensitive areas and endangered species habitat; Integrated Vegetation and Pest Management Plan; mitigating sensitive land off-site. • LSAG: Site Protection & Restoration • GRI • STARS: Wildlife Habitat • ISI NW1.1: Preserve Prime Habitat NR 3 Pervious Surface Percent of total airport landside surface area covered by permeable materials. • LSAG: Minimize Impervious Surfaces • CDA SAM: Stormwater Management • PANYNJ: Site Section IS-7 • Adapted by ACRP research team (continued on next page)

50 Prototype Airport Sustainability Rating System—Characteristics, Viability, and Implementation Options Table 4-2. (Continued). Sustainability Activity Performance Metric Sources HW 3 Light Pollution Performance is evaluated and points are awarded based on the number of performance actions pursued that address, for example, light level assessments, light pollution planning, siting and design considerations, and light shielding, among others. • LEED: Light Pollution Reduction • CDA SAM: Light Pollution Reduction • ISI QL2.3: Minimize Light Pollution • PANYNJ: Site IS-15 HW 4 Chemicals & Hazardous Materials Performance is evaluated and points are awarded based on the number of performance actions pursued that address, for example, chemical storage and labeling protocols, chemical inventories, enhanced employee education, spill protocols, and Environmental Management Systems for tracking and reporting. • LSAG: Indoor Chemical & Pollutant Source Control • LEED: Green Cleaning • CDA SAM: Sustainable Sites • STARS: Hazardous Waste HW 5 Passenger Experience Performance is evaluated and points are awarded based on the number of performance actions pursued that address, for example, natural lighting, effective signage and maps, satisfaction surveys, concession options, proximity to drinking water, and aesthetic enhancements, among others. • GRI: Product and Service Labeling • LSAG: Social Responsibility • LEED: Indoor Environmental Quality • CDA SAM: Indoor Environmental Quality HW 6 Employee Development Percent of airport employees who receive XX or more documented hours of elective training (Internal, External [on-site], External [off-site], and On-Line) per year by labor category. • GRI • STARS: Human Resources • Adapted by ACRP research team HW 7 Labor Relations Average percent annual employee retention rate across all labor categories. • GRI • STARS: Human Resources HW 8 Diversity & Equal Opportunity Performance is evaluated and points are awarded based on the number of performance actions pursued that address, for example, mentoring, counseling, peer support, affinity programs to support under-represented employees, equal pay programs, diversity recruitment, partnerships with local/regional workforce development organizations. Performance metrics could include minority employment percentage relative to regional minority employment percentage, among others. • GRI • STARS: Diversity & Affordability HW 9 Occupational Health & Safety Percent of total workforce represented in formal joint management–worker health and safety committees that help monitor and advise on occupational health and safety programs: mechanism to alert airport leadership regarding health and safety risks. • GRI Human Well-Being (HW) HW 1 Airport Noise Compatibility Performance is evaluated and points are awarded based on the number of performance actions pursued that address, for example, noise exposure mapping, incompatible land use areas, landside planning for non-aircraft noise, construction noise abatement plans, and local area complaint mechanism. • LSAG: Noise Pollution Reduction, Exterior Noise & Acoustical Control • CDA SAM: Noise Transmission, Construction Noise & Acoustical Quality HW 2 Workplace Air Quality Performance is evaluated and points are awarded based on the number of performance actions pursued that address, for example, achieving ASHRAE standards, complaint mechanisms, air quality studies, and contracting sustainability certified custodial service providers, among others. • LSAG: Indoor Environmental Quality • LEED: Indoor Environmental Quality • CDA SAM: Indoor Environmental Quality • STARS: Indoor Air Quality • GRI: AOSS

Development of Prototype Rating System 51 Table 4-2. (Continued). Sustainability Activity Performance Metric Sources DM 2 Material Selection Percent of total materials (as a portion of total material cost) sourced for any retrofit or expansion project consisting of environmentally preferable construction materials (i.e., recycled content, bio-based content, durable, local, rapidly renewable content, low embodied energy content, energy efficient, water efficient, green certified, reused on-site). • ISI RA1.3: Use Recycled Materials • PANYNJ: Material Multiple Credits • LEED: Materials & Resources DM 3 Construction Waste Diversion Percent of total construction & demolition waste diverted from a landfill or incinerator, in tons or cubic yards. • STARS: C&D Waste Diversion • PANYNJ: Construction IC-6 • FAA Recycling, Reuse and Waste Reduction at Airports DM 4 Construction Impacts Mitigation Performance is evaluated and points are awarded based on the number of performance actions pursued that address, for example, construction stormwater and air pollution control planning, inspection and maintenance planning, erosion and sediment control, dust suppression, vehicle washing, and equipment idling, among others. • PANYNJ: Construction IC-1 • CDA SAM: Construction Activity Pollution Prevention DM 5 Sustainable Site Selection Performance is evaluated and points are awarded based on the number of performance actions pursued that address, for example, siting assessments and mapping, siting action plans, rehabilitation and use of contaminated sites, and wetland maintenance, among others. • PANYNJ: Site Multiple Credits • LSAG: General Planning • LEED: Sustainable Sites • CDA SAM: Brown Field Redevelopment DM 6 Local Sourcing Percent of annual procurement contracts that include stipulations prioritizing the acquisition of products, materials, and services from businesses located within a certain distance from the airport. • STARS: Operations Credit 6: Purchasing • ISI RA1.4: Use Regional Materials • PANYNJ: Material Section: IM-2 • Adapted by ACRP research team DM 7 Recycled & Bio- based Content Percent of applicable products and materials purchased made at least partially from recycled or bio-based content, as a portion of total annual (or project) cost. Excludes fuels and electricity. Higher points may be available for sustainability harvested/generated products (e.g., Forest Stewardship Council (FSC) certified paper). • GRI: Environment Indicator EN2 • CDA SAM: Recycled Content • LSAG: Recycled Content • STARS: Purchasing • ISI RA1.3: Use Recycled Materials • PANYNJ: Material Section IM-1 • Adapted by ACRP research team DM 8 Low-Toxicity Materials Percent of applicable products and materials purchased that are third-party certified as low- toxicity, (e.g., EPEAT or Green Seal) as a portion of total annual (or project) cost. LSAG: Low-Emitting Materials STARS: Multiple Credits PANYNJ: Part 2: Material Section IM-6 Adapted by ACRP research team • • • • HW 10 Universal Design Performance is evaluated and points are awarded based on the number of performance actions pursued that address, for example, universal design elements and passenger/employee safety in new construction and retrofit projects, opportunity assessments for design upgrades, and enhanced safety and accessibility features, among others. • LEED for Neighborhood Development: Visitability and Universal Design • Greenroads: Access & Equity AE1 Safety Audit • ACRP research team Design & Materials (DM) DM 1 Sustainable Design & Operation Percent of total building space that achieves a self or 3rd party verified green certification – e.g., LEED®, Green Globes, ENERGY STAR, etc. • LSAG: Innovation in Planning & Design • CDA SAM: LEED Certified Project • STARS: Building Operations & Maintenance (continued on next page)

52 Prototype Airport Sustainability Rating System—Characteristics, Viability, and Implementation Options Table 4-2. (Continued). Sustainability Activity Performance Metric Sources EL 3 Community Stewardship Percent of airport employees that partake in 1 or more airport-sponsored community service projects or events per year; Tracking total hours of community service relative to total workforce hours. STARS: Community Service Adapted by ACRP research team EL 4 Integrated Sustainability Management Performance is evaluated and points are awarded based on the number of performance actions pursued that address, for example, integrating all sustainability plans (waste, water, energy, etc.) into airport Master Plan, incorporating sustainability into planning procedures and general reporting, appointing a sustainability coordinator, formal public reporting of sustainability, including sustainability metrics within environmental management system tools, and establishing a series of sustainability guidelines across airport functions. STARS: Coordination & Planning PANYNJ: Site IS-1 LSAG: Sustainability Planning and Progress Meetings • • • • • • CDA SAM: Planning EL 5 Airport User Engagement & Outreach Performance is evaluated and points are awarded based on the number of performance actions pursued that address, for example, communication, marketing, and education campaigns for sustainability at the airport, at home, and in the community. • GRI • LSAG: Community Education • STARS EL 6 Tenant & Vendor Sustainability Percent of vendor, concession, and tenant contracts that include clauses that address sustainability, social, and/or environmental concerns. • GRI Source: ICF, 2013 GRI: Global Reporting Initiative STARS: Sustainability Tracking, Assessment & Rating System ISI: Institute for Sustainable Infrastructure Envision™ PANYNJ: Port Authority of New York and New Jersey LEED: Leadership in Energy and Environmental Design CDA SAM: Chicago Department of Aviation Sustainable Airport Manual LSAG: Los Angeles World Airports: Sustainable Airport Planning, Design and Construction Guidelines 1 Scope 1 GHG emissions are emissions that occur from sources owned and controlled by the airport, such as airport fleet vehicles. Scope 2 GHG emissions are emissions that occur from purchased electricity and steam. 2 Scope 3 GHG emissions are emissions that occur as a result of the activities of the airport, but occur at sources owned or controlled by another organization (excluding purchased electricity and steam, which are Scope 2 GHG emissions). An example of Scope 3 emissions is emissions from landfilled waste. The emissions occur due to the decomposition of waste generated by the airport at a landfill, but the airport does not own the landfill. Engagement & Leadership (EL) EL 1 Airport-wide Stakeholder Engagement Performance is evaluated and points are awarded based on the number of performance actions pursued that address, for example, formal partnerships and standing committees with internal stakeholders. STARS: Public Engagement PANYNJ: Site IS-1 LSAG: Sustainability Planning and Progress Meetings CDA SAM: Planning EL 2 Public Outreach Performance is evaluated and points are awarded based on the number of performance actions pursued that address, for example, community outreach and informational programs, internships, etc. STARS: Public Engagement • • • • • DM 9 Environmentally Preferable Purchasing Performance is evaluated and points are awarded based on the number of performance actions pursued that address, for example, procurement requirements, product certification, contract tracking, and employee training, among others. GRI: Product Responsibility LEED: Material & Resources LSAG: Materials & Resources STARS: Purchasing: Multiple Credits ISI RA1.2: Sustainable Procurement • • • • •

Development of Prototype Rating System 53 The research team prepared definitions for each of the 50 sustainability activities to articulate the scope and extent of each. The definitions include: • A purpose statement that explains each activity’s value and provides a rationale for why the activity was included in the Prototype Rating System. • A definition that presents a general description of each sustainability activity, defines key terms, and outlines the type of airport functions that fall within the scope of the activity. • A description of primary related activities that describes how the sustainability activity is related to others and describes areas of overlap or shared themes. • A description of the performance metric (also included in Table 4-2) • Examples of supporting initiatives to provide examples of actions from the SAGA database and other sources that could lead to improved performance within the sustainability activity. The definitions provide the basic information needed to develop sustainability activity content for the Rating System User Guide. As an example, Figure 4-10 shows the purpose, definition, and related activities taken from the Waste Diversion User Guide Excerpt (see Figure 4-4). These definitions complement the User Guide excerpts, which provide examples of the full User Guide content for five example activities (see Appendix D). Definitions for all 50 sustainability activities are provided in Appendix E. Structural Component 4: EONS Icons The design specifications called for the rating system to adhere to the EONS framework. Implementing sustainability activities supports EONS. For example, consuming less energy supports natural resource conservation by lessening the environmental impact of fossil fuel extraction and combustion. However, a sustainability activity’s support of EONS is not neces- sarily exclusive to a single aspect of the EONS framework. Consuming less energy also supports economic performance because fewer dollars are spent purchasing energy from a supplier. To accommodate the possibility that an activity may support more than one aspect of EONS, the Figure 4-10. Example sustainability activity definition from the waste diversion User Guide excerpt.

54 Prototype Airport Sustainability Rating System—Characteristics, Viability, and Implementation Options Prototype Rating System incorporates EONS icons, which are symbols that identify the major aspects of the EONS framework that apply to an entire sustainability category (i.e., a set of activities supporting a similar sustainability theme). The EONS icons incorporate Harvey Balls that indicate the relative impacts of the category on each aspect of EONS. Harvey Balls are round ideograms used for visual communication of qualitative information. Commonly used in comparison tables to indicate the degree to which a particular item meets a particular criterion, Harvey Balls typically appear as follows: In the waste and water sustainability category, for example, the EONS icons for “O” and “N” are more complete than the icons for “E” or “S,” which indicates that while waste-reducing activities are important economically and socially, they are going to be most relevant to both operational efficiency and natural resource conservation (Figure 4-11). The symbols are intended to provide a comparison among the four aspects of EONS and do not represent a truly quantitative or measurable difference. They are designed to convey the crosscutting nature of EONS with the categories and help airports ensure they are diversifying their efforts across the EONS spectrum by pursuing activities from multiple categories. Within the User Guide, each sustainability category section will begin with a discussion of how each aspect of EONS pertains to that category. (See Appendix C for an annotated outline of the User Guide.) Using the human well-being category as an example, there would be a dis- cussion about how pursing sustainability performance across the activities within the category could impact positively the economic viability and operational efficiency of the airport as well as embody natural resource conservation and social responsibility. A Focus on Financial Considerations. Stakeholder outreach and discussions with the ACRP panel emphasized that economic considerations are particularly likely to span across all sustain- ability activities. Recognizing this need, the research team recommends incorporating financial considerations discussions into the body of the sustainability activity sections of the User Guide (see Figure 4-12). The financial considerations discussions focus on important financial concepts that airports should consider when pursuing each activity. Structural Component 5: Innovation The research team recognized that the Prototype Rating System could not capture every way in which an airport could demonstrate sustainability performance, and that the state of the sus- tainability field advances faster than the rating system could be updated. The performance action evaluation type (Evaluation Type 2), for example, may present some limitations on airport scor- ing because it does rely on a preset list of actions. These actions are high-level and designed to incorporate many smaller action types; however, because technologies and best practices evolve constantly, they may not capture the latest approaches toward achieving sustainability. Source: ICF, 2013 Figure 4-11. Example EONS icons.

Development of Prototype Rating System 55 To account for this, the research team recommends including an innovation mechanism similar to LEED that would allow airports to claim credit for new, innovative, or under-represented practices that still fulfill the objective of the sustainability activity. The rating system should award airports for exemplary performance that goes beyond what is included in the rating sys- tem. Within the scoring framework, airports can achieve up to a certain number of innovation points per innovative practice in each sustainability category added to the category score. The research team recommends including a documentation requirement in the rating system such that airports have to demonstrate that an innovation point was awarded for one of the following criteria: 1. The airport achieves significant, measurable environmental performance that exceeds the highest threshold of an existing credit. 2. The airport implements new, extraordinary, unique, groundbreaking, or uncommon outcomes, policies, and practices not addressed in the existing system. 3. The airport overcomes significant problems, barriers, or limitations to achieving sustainability. 4. The airport deploys sustainable solutions that are scalable and/or transferable across sectors, opening up new opportunities. Methodology. The research team reviewed how existing rating systems consider and incorporate innovation. The existing systems award innovation points for airports that either (1) achieve significant, measurable environmental performance that exceeds the highest threshold of an existing credit (LEED, STARS, ISI, LSAG, CDA SAM, PANYNJ) or (2) implement new, extraordinary, unique, groundbreaking, or uncommon outcomes, policies, and practices not Figure 4-12. Example financial considerations discussion from User Guide excerpt.

56 Prototype Airport Sustainability Rating System—Characteristics, Viability, and Implementation Options addressed in the existing system (LEED, STARS, ISI, CDA SAM). Across these systems, points are added at either the category level or at the system level (i.e., added to the overall score), and points may be limited to a certain number (e.g., six points) or a percentage (e.g., up to 5 percent of the total category points). The research team recommends incorporating a mix of the innovation requirements from each of the rating systems, as described above. Establishing a Rating The research team also developed a scoring framework to provide a mechanism for establishing a rating. The basic construct of the scoring framework is simple. Airports would score points for achieving levels of performance within each sustainability activity. Points earned across all sustain- ability activities would be summed, divided by the total points possible across all sustainability activities, and multiplied by 100 to determine a percent-based overall score. For example, if an airport earns 135 points out of 180 total possible points across all sustain- ability activities, then its overall score is 75 percent, as follows: Overall Score Total Points Earned Total Points Possible 135 180 0.75, or 75%.= = = To develop this scoring framework, the research team reviewed existing rating systems and assessed how each awarded points for activities and how those points would sum to an overall sustainability rating. (For a list of ratings systems reviewed, see the section “Drawing from Existing Rating Systems to Develop Categories, Activities, Metrics and Actions” in this chapter.) The details of how points are earned, how and why the total points possible can change from airport to airport, and the rating levels assigned to scores are described in the sections titled “Sustainability Activity Scoring,” “Applicability, Materiality, and the Scoring Framework,” and “Rating Levels,” respectively. Sustainability Activity Scoring Many existing rating systems score their activities using one or both of the following scoring frameworks: • An increasing number of points are awarded as performance increases relative to a metric (usually using percentage-based measures). • Single points (or small sets of points) are awarded for completing a specific action (binary scoring framework). The scoring framework used with the Prototype Rating System incorporates both of these scoring approaches: The percentage-based scoring framework applies to performance metrics (Evaluation Type 1), while the binary scoring framework applies to performance actions (Evaluation Type 2). Please note: The Prototype Rating System offers a scoring framework only. Determining appropriate performance thresholds, assigning points to threshold levels, and determining the appropriate number of points available for each sustainability activity would occur under future work. Under Evaluation Type 1, airports measure performance relative to a single, broad perfor- mance metric such as percent solid waste diverted. Percent-based thresholds (e.g., 10 percent or 20 percent) indicate increasing levels of performance for the performance metric, and points are associated with each performance threshold. Higher performance thresholds demonstrate increasingly improved performance and are worth more points (Table 4-3).

Development of Prototype Rating System 57 Under Evaluation Type 2, airports measure performance by completing actions from a menu of performance actions. Performance actions are measures the airport could take to improve performance within the sustainability activity (e.g., “prepare a vulnerability assessment” for the sustainability activity climate change adaptation). These actions are binary in nature, meaning an airport either has or has not taken the action. Points are earned by performing a greater number of actions within a sustainability activity. Higher performance thresholds reflect a greater number of actions the airport must fulfill to receive points (Table 4-4). Tables similar to those presented in Tables 4-3 and 4-4 would be provided for each sustainability activity to indicate the number of points earned for achieving levels of sustainability performance (see Figures 4-10 and 4-11). A maximum of four performance levels would be provided within each sustainability activity, but not all sustainability activities would have four performance levels. The number of levels would depend on the nature of the activity. Points would be awarded by level, with the highest points awarded for superior performance. For illustration purposes, performance levels could include “Take-Off,” “Ascend,” “Cruise,” or “Soar,” which mirror the category and overall rating levels (see the section titled “Rating Levels”). Prerequisites. In some cases, performance actions or performance metrics might be deemed to be strategic or necessary for any truly sustainable airport activity. Therefore, these actions or metrics would be considered prerequisites, and be required to achieve any points for that sustain- ability activity. In many cases, prerequisites would likely fall at the performance threshold of the Take-Off performance level. Prerequisites preserve the integrity of the rating system by requiring that minimal levels of performance be met where appropriate. Prerequisites would likely be incorporated primarily into Evaluation Type II, wherein an action would be required to achieve a performance threshold and would be identified as such in the list of performance actions. For example, a prerequisite for the Take-Off performance level for the airport noise compatibility sustainability activity might be to “develop a noise exposure map.” Thus, to meet the performance threshold to achieve the Take-Off performance level for this sustainability activity, an airport would need to develop a noise exposure map and complete two performance actions. Similarly, prerequisites could be developed and applied where appropriate to the thresholds for the Ascend, Cruise, and Soar performance levels (see Figure 4-13 for an example). The determination of prerequisites would be detailed in future efforts. Performance Level Take-Off Ascend Cruise Soar Threshold 10% 20% 30% 40% Points 1 2 3 4 Source: ICF, 2013 Note: Performance-level titles and values are illustrative only. Table 4-3. Evaluation Type 1 (performance metric) point allocation example. Performance Level Take-Off Ascend Cruise Soar Threshold 2 Actions 4 Actions 6 Actions 8 Actions Points 1 2 3 4 Source: ICF, 2013 Note: Performance-level titles and values are illustrative only. Table 4-4. Evaluation Type 2 (performance actions) point allocation example.

58 Prototype Airport Sustainability Rating System—Characteristics, Viability, and Implementation Options Category-Level Scoring Based on feedback from stakeholder outreach to the airport industry, medium and smaller airports are also likely to use the rating system primarily as guidance for starting, improving, or expanding a sustainability program rather than for rating overall performance. The flexibility that this offers is a distinguishing feature of the Prototype Rating System. Stakeholders also recom- mended that the rating system allow for scoring at the category level in addition to the activity and system level so that airports could gauge their performance at various levels of adoption and progress smoothly toward a fuller adoption of the system over time. Figure 4-13 demonstrates how the points across all activities within a category could be summed and given a rating similar to the activity performance levels (see “Sustainability Activity Scoring”) and overall rating levels (see “Rating Levels”). A possible number of points is defined for each category and thresholds are given for obtaining a particular rating at the category level. Applicability, Materiality, and the Scoring Framework A key finding in the stakeholder outreach process was that the rating system needed to accom- modate differences in airport characteristics. Not all sustainability activities will be applicable or material to all airports. Materiality is used to describe whether a sustainability activity is sufficiently applicable that it should be included within an airport’s rating. As an example, the construction waste diversion sustainability activity would not be material to an airport if no construction occurred during the year when the rating was applied. Another example is passenger experience sustainability activity, which would not be material to airports that are not geared toward passengers, such as cargo airports. Generally, the broad nature of sustainability activities in the Prototype Rating System would accommodate most airports, lessening the need for applying a materiality judgment to an activity. The scoring framework incorporates materiality by indicating that airports should identify those sustainability activities that are material to their infrastructure, operations, and management when preparing a rating. If sustainability activities are not material, they should be excluded from the rating and the points associated with that sustainability activity should be deducted from the total points possible. Figure 4-13. Example category-level scoring. Source: ICF, 2013 Note: Example scores are for illustration purposes only.

Development of Prototype Rating System 59 If, for example, the total points possible across the entire rating system is 180 points and several sustainability activities totaling to 30 points are deemed immaterial to an airport, those 30 points would be subtracted from the total points possible, yielding a revised total possible points of 150. In this example, if the airport earns 135 points, its overall score would be 90 percent (135/150 = 0.90, or 90 percent). Incorporating materiality makes the Prototype Rating System more flexible and able to accommodate different airport types, roles, and sizes, because airports select those sustainability activities that are material to their operations to include in the rating. Materiality should be an objective determination based entirely on whether an activity actually occurs at the airport. For those airports that self-determine their ratings, the determination of materiality would be left entirely to the airport. This is not a concern if the airport uses the rating system primarily for internal evaluation and improvement; however, if airports choose to compare their ratings with other airports, those airports that self-determine their ratings should be encouraged to share the total points considered in determining their overall score so that exceptions made due to materiality considerations are transparently presented. Doing so would lessen concerns that airports may improperly apply materiality to determine more favorable ratings while maintaining a rating system that does not require third-party certification or verification. Stakeholder feedback indi- cates that many airports may likely use the rating system for internal evaluation purposes only and that interest in external certification and verification may grow in time. These concepts are explored further in the section titled “Viability of the Rating System.” Rating Levels Once an overall score is established, it can be used to determine a rating level. As discussed in the previous sections, the overall score is calculated as a percentage of total points earned out of total points possible across all sustainability activities. An airport’s overall score value can be used to determine a rating using a rating scheme similar to that presented in Table 4-5, wherein the overall score falls within a rating tier that indicates the minimum number of points required to reach a rating level. For example, using the information provided in Table 4-5, an airport that earns a score of 75 percent would receive a “Cruise” rating. Please note: The rating names— “Soar,” “Cruise,” “Ascend,” and “Take-Off ”—and the tier levels are included for illustrative purposes only in this Prototype Rating System. The rating levels and tiers would need further development in future work. 4.4 Viability of the Rating System Introduction The research team also assessed the viability of industry-wide adoption of a completed draft Airport Sustainability Rating System and voluntary certification program. To do so, the research team considered the implementation options available for the rating system, likely users of the Rating Level Tier Threshold * Soar 85% Cruise 65% Ascend 45% Take-Off 25% Source: ICF, 2013 Notes: Rating level terms and tier values are illustrative only. *Percentage of total possible points. Table 4-5. Example rating levels and tiers.

60 Prototype Airport Sustainability Rating System—Characteristics, Viability, and Implementation Options rating system, what entity might be responsible for implementing and maintaining the rating system, and the functions and costs needed for implementation and maintenance. The remainder of this chapter discusses the following points: • Purpose and likely use of an airport sustainability rating system. • Rating system development and implementation options—including certification and verifica- tion options. • Rating system viability. • Summary of viability conclusions. Purpose and Likely Uses of an Airport Sustainability Rating System A sustainability rating system is a tool for evaluating and driving sustainability performance through a system of best practices and recognition. Well-designed rating systems can facilitate meaningful comparisons over time via a common set of measurements; incentivize continual improvement through recognition and scoring; and encourage the identification and sharing of best practices. In the context of ACRP Project 02-28, the purpose of the airport sustainability rating system would be to encourage airports to pursue sustainability, measure and track their internal performance across standardized metrics, and possibly to benchmark their progress against other airports in the United States in the future. A collection of standard, accepted guidance, the rating system would serve as a resource with state-of-the-art sustainability best practices and a mechanism for evaluating performance. The rating system would also enable airports to improve relations with the community and customers by communicating sustainability successes both nationally and to local stakeholders (e.g., travelers, employees, airlines, and community members), educating stakeholders, and justify- ing and highlighting the importance of sustainability management. Tracking performance more closely could also help facilitate enhanced environmental compliance processes. The Prototype Rating System would provide a framework for internal sustainability performance evaluation and tracking through a common set of activities, metrics, and actions, plus a scoring framework to support optional external comparisons. Similar airports that opt to make external comparisons could do so for both competitive purposes and to learn from and benchmark against other airports. The rating system would provide participating airports the flexibility to use it in the way that best suits their needs and resources without requiring high performance across all activities. Because performance could be scored and tracked at the activity and category levels, in addition to the system (i.e., airport-wide) level, airports could gauge their performance at whichever level of adoption is most appropriate for them, then progress easily toward a fuller adoption over time. The flexibility built into the rating system also could allow selective prioritization of the activi- ties and categories. Airports could choose which activities and categories most resonate with their stakeholders and adopt activities on a case-by-case basis, or pursue a more comprehensive approach (i.e., implementing a complete set of activities within a category or the entire rating system). The airports could gauge their progress based on a performance baseline before they adopt the rating system. Eventually, with a mature governance structure in place, airports could potentially compare their performance with other airports. Potential Users Possible users of an airport sustainability rating system include commercial service, cargo service, reliever, and general aviation airports; however, use of the rating system would likely vary among large, medium, and small airports. Based on stakeholder feedback, larger airports with

Development of Prototype Rating System 61 full-time dedicated environmental staff have more available resources to pursue sustainability ratings. The larger airports could use the rating system to track performance internally and gauge performance against other, similarly large airports. Alternatively, airports may wish to supplement their existing programs using guidance from specific sustainability categories, then track and compare performance, if desired, given that the rating system allows for scoring at the sustain- ability category level. For example, a large airport that has a well-established environmental program may choose to focus on its performance in categories such as human well-being or economic performance in order to pursue other less-developed components of sustainability. As a group, larger airports are more likely and capable of pursuing a greater number of sustain- ability categories within the rating system, which may translate to several categories or the entire system as a whole. However, some of the larger airports have indicated that they would likely first use their own independently developed ratings systems, and a few airports expressed concerns about additional performance tracking. Based on feedback from stakeholder outreach to the airport industry, medium and smaller airports are also likely to use the rating system; however, they may use it primarily as guidance for starting, improving, or expanding a sustainability program rather than rating overall per- formance. Such airports could take advantage of the rating system’s best practices and metrics. The rating system could help these airports evaluate and prioritize sustainability activities as it relates to their planning, construction, and daily operations. For example, smaller airports may target certain sustainability activities relevant to their operations, and then expand their efforts to other activities in the same category. Because performance can be scored and tracked at the activity, category, and rating system (i.e., airport-wide) levels, airports could gauge their performance at various levels of adoption and progress smoothly toward a fuller adoption of the system over time. Although stakeholders and the airport community remain divided on whether an airport sustainability rating system should be used for internal purposes only or for external use and comparison, the effect this decision will have on certification and verification options is clear (Table 4-6). Those who favor internal use of the tool are likely to advocate for a rating system that functions primarily as a best practices manual or guidance, while those who favor external use are likely to favor more rigorous certification and verification procedures. Many stakeholders favor internal use and believe that this lower-cost option will keep the rating system accessible to all airports and drive adoption of the tool. Those who favor external use believe a more formal certification and verification process—with associated administration and governance—is critical for credibility. Rating System Development and Implementation Options This section presents the steps that would be needed to develop draft and final versions of the airport sustainability rating system as well as potential implementation options. Rating System Implementation Options ACRP Report 119 concludes Phase II of the development process for the Prototype Rating System, which covers the scope of work for ACRP Project 02-28. The next steps would be for the airport community to determine whether to move forward with preparing a full draft rating system and pilot the draft rating system at airports. Following pilot projects and any revisions that would come out of the pilot effort, when the rating system is ready for release to the air- port industry there would be a need for a permanent governance organization. The governance organization would be responsible for the release, administration, and governance of the rating system. The level of administration and governance required would depend on the robustness

62 Prototype Airport Sustainability Rating System—Characteristics, Viability, and Implementation Options of certification and verification procedures that would accompany the rating system. Potential administrative and governance functions include: • Administrative Oversight. Provide staffing, site, and ongoing program support functions. • Rating System Advisory Committees. Obtain expert stakeholder input on a regular basis to maintain relevancy, optimize usage, and connect with the broader airport community. • Formal Rating System, Certification, and Verification Training. Provide users with detailed information on scoring and certification requirements, and empower professionals by creden- tialing certifiers and verifiers. • Stakeholder Communication. Identify, inform, and engage willing airport-industry participants. • Rating System Updates. Solicit user feedback and stay ahead of changes in industry best practices and standards. At a minimum, the governance organization would need to have a method to communicate with users and stakeholders, receive and respond to their suggestions, and issue updated versions of the rating system, most likely through an on-line platform. More active and well-resourced administration and governance could include trainings, professional credentialing to issue certifications, stakeholder working groups, procedures for verifying certifications, and collection of airport performance data to support benchmarking. Assessing the viability of a rating system requires understanding the options for certifying and verifying a sustainability rating and thus the amount of administration and governance that would be required. Consideration would also need to be given to the current context for sustain- ability planning and the airport industry. More robust certification and verification procedures would require more administration and governance. Figure 4-14 presents four implementation options that fall along a spectrum of increasing system administration and governance needs, Certification & Verification Options First-party certification Often referred to as self-certification or self-determination: internal determination that the airport meets the requirements of a rating level made by the same airport staff that is responsible for compiling the data and documentation use to determine the rating level. Second-party certification A determination of the rating level made by at least partially independent staff with an appropriate understanding of rating system requirements. If made by internal staff, they are other than those who are responsible for compiling the data and documentation used in support of the rating level (i.e., at least one step removed from developing the data that supports the rating). Second-party certification also can be conducted by a peer organization, for example, by staff with appropriate expertise from another airport or even within a network of airports. Second-party verification Verification of the rating determination for the airport confirming that the data and documentation used to determine the rating level are accurate and complete and that the resulting rating is appropriate and made by individuals at least one step removed from the development of the data and the determination of the rating. Third-party certification External determination of the rating level made by an organization that is not affiliated with the airport. Third-party verification Verification of the determination of the rating for the airport confirming that the data and documentation used to determine the rating level are accurate and complete, and that the resulting rating is appropriate and made by an independent organization that is not affiliated with the airport and is free from real or potential conflict of interest in its determination. Table 4-6. Certification and verification options—definitions.

Development of Prototype Rating System 63 as well as increasing capital investment and operational expenses. The options are described in detail after Figure 4-14. Each demonstrates a possible viable deployment option of the rating system, along with their respective certification and verification requirements. These should serve only as examples, and it is up to the industry to determine which option, or variation thereof, is most viable and appropriate. Best Practices and Metrics Manual. The basic level of implementation would involve the distribution of the rating system as a sustainability guidance document that contains best practices, useful metrics, and evaluation techniques. Airports would utilize the manual to start, improve, or expand upon an internal sustainability program by pursuing as many performance actions and sustainability activities as feasible given the airports’ needs and resources. This option involves minimal investment and operational expenses beyond the initial development and piloting of the rating system. The rating system material would need to be available for distribution on-line, either through a dedicated website or through a partner entity sponsoring the system. Updates would occur as necessary. The SAGA website is a stand-alone tool and a comparable example of this level of governance; it only requires a host website and periodic updates to perform its useful function. Self-Certification Rating System. The second-tier option would be a self-certification rating system in which airports would evaluate and certify their own performance based on the activities and metrics in the rating system, along with support from on-line resources for inter- nal certification and self-reporting. Effectively, volunteers or shared employees from an airport Source: ICF, 2013 Note: The ISI Envision™ system is in the process of establishing a certification process to be performed by credentialed professionals. Figure 4-14. Airport Sustainability Rating System implementation options.

64 Prototype Airport Sustainability Rating System—Characteristics, Viability, and Implementation Options association would serve as a “virtual staff” to provide a minimal level of engagement or regular oversight functions, necessitating a minimal resource commitment as necessary to execute basic functions. To minimize related administrative cost, this option might leverage an existing organization’s or association’s expert committee skills to serve as an advisor group. Web-based educational resources with pre-recorded workshop and informational webinars from experts could teach airports how to utilize the rating system, and web-based forms and worksheets could be provided for airports to track their own sustainability progress. Communication could be done on a sustainability rating system website with announcements and updates on at least an annual basis, complemented by live updates at relevant conferences. Limiting revisions to the ratings system to when they are necessary (once a year at most) would limit the need for labor and funding. Additionally, the advisory committee could potentially lead the effort, and they could serve as the conduit to incorporate broader stakeholder input. Envision™ and the LEED “alternative compliance pathway” for non–United States projects are examples for this level of governance. LEED alternative compliance paths provide additional options to LEED credits that address unique project needs and advancements in technology, specifically for projects outside the United States. For more information, see www.usgbc.org. It is acknowledged that Envision™ also is moving toward higher levels of governance. Both systems provide users a framework, and the implementers are responsible for establishing a performance level. Rating System and Verification Administration. The third option provides a more rigorous mechanism to evaluate and verify airport performance and to benchmark against other airports. Certification is required by independently credentialed professionals (e.g., certified energy man- agers) to bring credibility to the rating. Self-ratings would be managed by internal airport review committees and submitted to the rating system administration entity for a formal verification of documentation. On-line tools and formal training would also be more necessary to standardize certifier and verifier knowledge and requirements. Dedicated staff with a moderate level of engagement could maintain regular communication with stakeholders, liaison with an advisory committee, and maintain a website and data resources for airport participants. Such a system would require regular meetings of a dedicated advisory committee (or topic-specific committees) with a singular focus on improving the sustainability rating system. On-line training would be augmented by live classroom instruction and scheduled workshops on the sustainability ratings system. Live training could occur at conferences, airport venues, or at college and university campuses. Workshop curricula could be designed in advance and reviewed by the advisory committee. A monthly (or quarterly) listserv message would also be beneficial, and system updates could follow a formal cycle, soliciting feedback actively on the website or at conferences. The existing version of the rating system could incorporate these revisions without having to conduct an open, public review of the material. This option would provide for a durable program that could implement changes on a faster basis to refine the early rating system and to promote it. The ENERGY STAR program is a comparable example of this level of governance. The rating system requires that an independent professional submit the certification package to ENERGY STAR for review. ENERGY STAR requires that the submitting individual have a specific set of credentials (e.g., be a registered architect or a professional engineer), but does not create unique credentialing or oversight of the training credentials. Rating System and Independent Certification and Verification. The fourth option is the most intensive approach and would establish two fully independent organizations: one to administer the rating system, and one to administer the certification and verification duties. With the highest level of engagement, both dedicated staff and dedicated office space would be necessary to provide active responses to airport inquiries, host trainings and web meetings, and perform the administrative

Development of Prototype Rating System 65 duties required of the system. The staff and office would require sizable resources and substantial funding would be necessary for both the initial and ongoing operating costs. In addition to all the considerations listed in the third option, this option might require multiple technical advisory groups that specialize in each of the eight categories and can pro- vide more rigorous and informed guidance for updating the rating system and responding to stakeholder needs. Such a system could have professionally accredited professionals who attend live workshops, study rating system content, and take proctored exams to assess their understanding. Additional costs for the testing could be covered by participant fees. To achieve a higher level of recognition and participation, dedicated conference events at an existing conference (e.g., Airports Going Green) or a new annual conference could serve as a venue for industry to showcase new products and services as well as involve other green building affinity groups. At the highest level, a formal cycle could include complete version overhauls of the rating system every 3 years or so. Draft documents could be made available to airport stakeholders for their review, with comments tracked and recorded. The USGBC’s LEED system and the independently established Green Building Certification Institute (GBCI) are examples at the most resource intensive level of governance. USGBC main- tains the sustainability rating system for buildings and the related guidance duties. GBCI runs the credentialing of professionals and the certification of the buildings themselves. This double-entity approach allows LEED to have a tailored system of professional knowledge via USGBC, plus the third-party validated testing for professionals and the buildings. Rating System Viability An airport sustainability rating system requires a thoughtfully planned and well-executed implementation approach. Airport adoption depends on stakeholder interest, on functional benefits gained by participation, and on existing alternative methods to rate sustainability per- formance. Governance also plays a key role. A permanent hosting organization would be needed for the rating system once it had completed the design phases. The market for these services would need to be assessed before making additional sizable investments to a rating system. This section covers these critical aspects of governance and their impact on viability by reviewing the governance requirements, providing implementation case studies from other rating systems, and assessing the demand for a rating system and certification/verification program. Governance Responsibility Once the rating system was ready for release to the airport industry, a need would arise for a permanent governance organization. The governance organization would be responsible for exe- cuting the administrative tasks described in the section titled “Rating System Development and Implementation Options,” including the release, administration, and governance of the rating system. Given its research mission, it is assumed that ACRP would not be the ideal organi- zation to assume the governance role. Existing airport trade associations may be potential candidates to host the system. Governance Staffing and Costs Each implementation option described in the “Rating System Development and Implemen- tation Options” section is a viable approach for releasing the rating system and for providing certification and verification procedures. Funding would be necessary for ongoing administration and governance regardless of the option that is chosen; however, the costs associated with an

66 Prototype Airport Sustainability Rating System—Characteristics, Viability, and Implementation Options independent certification and verification process (the most intensive approach) would likely far exceed the costs of a Best Practices and Metrics Manual (the least intensive approach). Table 4-7 provides an estimate of the costs associated with rating system governance and certification and verification procedures by function. For the purpose of this evaluation, the costs are broken into capital investment (what airports commonly refer to as capital expense or Capex) and operational expenses (also called Opex) for each of the implementation options. Capital Governance/ Certification Function Best Practices & Metrics Manual Self-Certification Rating System Rating System & Verification Administration Rating System & Independent Certification and Verification CE OE CE OE CE OE CE OE G ov er n an ce Administrative oversight $25–50K $5–15K $25–75K $5–15K $50–150K $250–750K $250–750K $250–750K Rating system advisory committee $5–15K $5–15K $5–15K $5–15K $50–150K $5–15K $50–150K $50–150K Practitioner rating system training $150–300K $5–15K $250–750K $5–15K $250–750K $50–150K $0.5–1.5M $50–150K Stakeholder communication $25–75K $5–15K $25–75K $5–15K $50–150K $50–150K $250–750K $250–750K Rating system updates $50–150K $5–20K $50–150K $5–20K N/A $50–150K N/A $50–150K Ce rt ifi ca tio n & Ve rif ic at io n Certification/ verification process design N/A N/A N/A N/A $250–750K $250–750K $0.5–1.5M $250–750K Certification/ verification advisory committee N/A N/A N/A N/A $50–150K $50–150K $50–150K $50–150K Certifier/verifier training N/A N/A N/A N/A $250–750K $50–150K $0.5–1.5M $250–750K Certification administration and communication N/A N/A N/A N/A N/A N/A $250–750K $0.5–1.5M Verifier administration and communication N/A N/A N/A N/A $5–15K $5–15K $250–750K $250–750K TOTAL COSTS (average) $420K Investment $52K Annually $710K Investment $52K Annually $1.91M Investment $1.52M Annually $5.20M Investment $3.90M Annually Note: Capital expense (CE) is a one-time expense, and operational expense (OE) is an annual funding requirement. Table costs were estimated given the assumed labor-hours (and hired staff) required to perform each of the functions. Labor-hours were estimated using a basic project management tool. N/A denotes that the function is not applicable to the implementation option. Table 4-7. Governance and certification/verification estimated capital expense and operational expense costs by component.

Development of Prototype Rating System 67 expenses include first costs associated with starting a new program service and are not com- monly recurring expenses. For example, designing and deploying a new website would initially be a capital investment. Maintaining that same website in the second year would be an opera- tional expense. The hosting organization that assumes responsibilities for implementation of the rating system may consider adopting the related functions down the entire set of a single engagement level or, alternatively, selecting functions from multiple levels to create a blended approach. Existing Sustainability Rating and Reporting Systems—Case Studies To assist with evaluating the available options for implementing the rating system, the research team reviewed the implementation approach used by other sustainability rating systems. The case studies in this section provide an overview of the implementation approach used by five similar sustainability rating systems. Four of these systems involved major organizations and required over 5 years to produce and at least $2 million of capital investment. The individual airport sustainability rating systems could be generated for much lower investments, but likely have limited ability for practical use at secondary locations by outside stakeholders. Case Study 1: Leadership in Energy and Environmental Design (LEED) Governing Body. U.S. Green Building Council (USGBC) Resources to Implement. USGBC relied on significant volunteer time to implement LEED. USGBC estimates that it required 200,000 volunteer labor-hours, equivalent to 100 full-time employees for 1-year. Assuming that the labor was worth an average of approximately $50 per hour fully loaded, the cost to implement LEED was at least $10 million. USGBC secured revenue sources from the Greenbuild annual conference, membership fees, professional accreditation programs from greater than 10,000 individuals, publications (including the reference manual for the system itself), and, in the beginning, certification fees from the candidate building teams under consideration. By 2008, annual revenue from these sources exceeded $10 million. In 2008 the GBCI spun off from USGBC to create independent oversight of the building certification and professional credential programs. Structure. LEED is a project-focused sustainability rating system that provides weighted point scoring for sustainability performance measurements and actions for buildings (primarily new construction). The rating system’s purpose is to promote environmentally sustainable design, construction, and operation of buildings. USGBC maintains the current rating system and issues regular updates with input from advisory committees and external stakeholders. In addition, USGBC maintains the credentialing training for professionals to assist building design teams. The independent GBCI oversees actual credential testing and renewals. The accredited profes- sionals are not mandatory for certification. Building certification is also conducted by GBCI. Sustainability Scope. LEED’s most common product is the rating system focused on new construction and major renovation projects. Operationally, the existing building operations and maintenance (EBOM) program covers the building and adjacent grounds for conventional buildings. There is no coverage for airport-specific operations or spaces. Airport Applicability. LEED has strong recognition across airports and among airport stakeholders. Multiple airports have LEED-certified terminal buildings or control towers. A number of larger hub airports and airport authorities have based their own airport-specific sustainability guidance on LEED principles and categorization. LEED does not currently address horizontal infrastructure such as runways, ground support equipment (GSE), ground access

68 Prototype Airport Sustainability Rating System—Characteristics, Viability, and Implementation Options vehicles (GAV), and other airport airside-related assets. It should be noted that airports have pursued two LEED product options: building design and construction (BD&C) and EBOM. Although dozens of airport BD&C-certified new construction projects exist, there are no airport EBOM-certified projects, even though there are over a dozen airports that have initiated the LEED process and registered for existing buildings. This may suggest that LEED is more appropriate for new construction and retrofits at airports, and the operations-focused option for existing infrastructure may not be well tailored for airports. Timeline to Implement. the USGBC was formed in 1993 and released its first green building rating system in 2000—seven years later. As the rating system has matured, it has added specific type of building certifications (e.g., schools and hospitals), components of buildings (e.g., commercial interiors and core & shell), groups of buildings (e.g., campus and neighborhood development), and existing buildings (e.g., existing building operation & maintenance, covered in the previous paragraph). Case Study 2: Individual Airport or Airport Authority-Tailored Systems Governing Bodies. Airports/Airport Authorities, including CDA, LAWA, and PANYNJ. Resources to Implement. Many of the airports’ individual sustainability rating systems were modeled after the LEED system and thus saved resources. Other airports hired consultants to design their systems, issuing requests for proposals with costs under $1 million and a require- ment of less than 2 years to design. It is unknown how much funding is allocated to update the systems. Structure. Airports with the interest and resources have created their own rating systems for sustainability, borrowing from other systems (such as LEED). The purpose of the independent airport-authored systems is to provide a method to cover buildings and operations that goes beyond the scope of LEED and helps to advance sustainability principles above the standard airport conventions. Individual airports decide how and when they want to apply their own system and provide their own verification. These systems tend to be project-focused. Sustainability Scope. Airports’ self-created sustainability rating systems range in scope from airport to airport. Most systems address new construction projects and some extend cov- erage to operations. Airport Applicability. Each independent airport-designed system is designed to support the scale and functions of the unique airport it serves and therefore may have limited applicabil- ity to the medium and small airports that might benefit from borrowing the approach. Timeline to Implement. The research team estimates that airports’ individual rating sys- tems required approximately 2 years to develop and begin implementation. Case Study 3: Envision™ Governing Body. ISI Resources to Implement. ISI formed in 2008 as a partnership between the American Council of Engineering Companies (ACEC), American Public Works Association (APWA), and the American Society of Civil Engineers (ASCE). As with LEED, many thousands of volunteer hours were required for ISI to produce a first-draft of the rating system. Anecdotally, the actual costs for ISI have been at least $3 million to date. In addition, before partnering with ISI to collaboratively release the Envision™ rating system in 2012, the Harvard Graduate School of Design (GSD) had spent approximately 3 years with paid academic researchers and volunteer

Development of Prototype Rating System 69 collaborators creating the Zofnass Sustainable Infrastructure system. The associated costs of the Zofnass Program are unknown, and funding to establish the program came from a single external benefactor. ISI generates revenue from membership fees and professional credentialing. Structure. The Envision™ system was created to address the system sustainability aspects of infrastructure not covered in the LEED system (e.g., roads, water treatment plants, etc.). Envision™ also goes beyond the physical properties and performance of structures to cover social and economic concerns, such as project-relative contributions to the local economy. ISI maintains the Envision™ system and the professional credentialing program. Participants can currently adopt the system and then self-certify. Envision™ is project-focused. ISI is setting up Envision™ for certification by a third-party provider. Sustainability Scope. Envision™ can cover all airport functions. Airport Applicability. Airports are gaining familiarity with this system, although it is likely that a small informed group has knowledge at present. ACI-NA hosted a webinar on Envision™ and has formed a committee—the Sustainable Airport Workgroup (SAW)—to explore adapting the Envision™ System for airports. Implication for Viability. Envision™ may be the strongest alternative to the Prototype Rating System. At the very least it is recommended to explore coordination and collaboration between the two systems. Timeline to Implement. Envision™ required about 3 years for the first pilots and another year before the first system was released. At the time of ACRP Project 02-28, the only Envision™ airport project moving toward certification was San Diego’s new terminal. Case Study 4: AOSS Governing Body. GRI Resources to Implement. GRI was started in 1997 by the non-profit organizations Ceres and Tellus Institute with the support of the United National Environmental Program (UNEP). It became an independent institution in 2000 and is on the fourth version of its disclosure protocols, which include the Airport Operators Sector Supplement (AOSS). The total annual budget for GRI is over $8 million and it obtains it revenue from donations and user fees. Structure. GRI was established to promote transparent sustainability accountability for private firms and other organizations. An organization or firm must track metrics that it might not have focused on without GRI, and publication of the report provides incentive to improve performance. The GRI’s systems and supplements, such as the AOSS for the airport sector, do not rate achievement levels. GRI manages its system of sustainability metrics for benchmarking various industry sectors and provides periodic updates. GRI’s intent is to promote transparency and tracking; it is a reporting system, not a rating system. Organizations that utilize GRI report on a broad number of metrics and, presumably, they are inclined to show progress on these measures. Individual participants pay fees to register with GRI and then conduct their own measurements and reporting based on sector-defined common metrics. There are two options, (1) no certification, and (2) the elective and more rigorous “+” designation, which requires the annual report to be independently verified by a third party. GRI’s airport sector supplement addresses airport-wide performance and is not project-level focused. Sustainability Scope. GRI’s AOSS covers all airport functions. AOSS indicators span envi- ronmental performance, social/employment indicators, and financial/economic measures. The GRI is a system of reporting metrics but does not include a rating component.

70 Prototype Airport Sustainability Rating System—Characteristics, Viability, and Implementation Options Airport Applicability. A few airports have published GRI reports (e.g., Dallas/Fort Worth International Airport and Toronto Pearson International Airport) and airport environmental leaders are aware of the system. It is likely that, outside the core of environmental technical staff at large airports and involved airport-industry participants, GRI knowledge is limited. Timeline to Implement. GRI required 3 years to form is own organization and offered pilot programs shortly after that time. Approximately 3 years was required for GRI to develop the AOSS. Case Study 5: ENERGY STAR Governing Body. EPA Resources to Implement. ENERGY STAR is a federal partnership between EPA and DOE. Started in 1992, its current annual budget is in excess of $50 million, covered by the EPA. ENERGY STAR has multiple components, including Portfolio Manager, which relies on building industry data gathered by the Energy Information Agency (EIA) Commercial Building Energy Consumption Survey (CBECS). The program includes an on-line tool for registering and assessing buildings, a mechanism to review certification submissions, and plaques for buildings that achieve an ENERGY STAR certification rating (75 percent or above). Structure. EPA and DOE created the ENERGY STAR program as a voluntary approach to achieving environmental and energy improvement without additional regulations. By recognizing superior equipment and building performance, EPA believes that consumers will value the option to purchase products with lower operating costs and manufacturers and building operators will be incentivized by the branding benefits. ENERGY STAR maintains the benchmarking tool and stores the building energy performance information. Baseline data is obtained from the external EIA via its irregularly scheduled building censuses. Verification/validation is performed by third-party general professionals with either engineer or architecture credentials. The third party compiles and submits the application. Building candidates are responsible for verification/validation costs for the third party. Awards are issued by ENERGY STAR. Administrative costs are born by the federal government. Facility applicants do not pay EPA or ENERGY STAR to apply. EPA believes its significant budget allocation is justified given the large efficiency benefit the program has helped to catalyze, estimated at $14 billion in consumer energy costs annually in 2006 alone. Sustainability Scope. ENERGY STAR only covers buildings and energy consumption. There is no current specified airport building profile within ENERGY STAR (e.g., terminals, hangars). Airport Applicability. High, as the program has strong recognition among building engineers as the authoritative benchmark for building energy performance; however, it is only applicable to buildings. Timeline to Implement. ENERGY STAR started with other programs, such as appliances, before it created the Portfolio Manager. It is estimated that it took over 5 years to implement the building rating system. Airport Market Assessment An understanding of the demand for a rating system may help determine next steps for research. It may also provide background for a possible future rating system governance organization to determine an appropriate certification and verification program. Although a robust mar- ket assessment was outside the scope of ACRP Project 02-28, this section provides some initial perspective based on the results of the stakeholder outreach efforts and feedback from the airport community during Phases I and II of this study.

Development of Prototype Rating System 71 The Phase I stakeholder outreach resulted in five design specifications that were used to develop the Prototype Rating System. These design specifications encompassed the need for an airport sustainability rating system. Whether the Prototype Rating System would be viable if finalized and released to the airport industry may, in part, be evaluated by considering whether the rating system is likely to meet the design specifications. Table 4-8 compares the design specifica- tions against the scope of the Prototype Rating System as well as other existing rating systems. During the Phase II stakeholder outreach, airport-industry representatives were asked whether their airport or airport client(s) would be likely to use the Prototype Rating System. They were also asked (1) if the rating system should be used for internal use only or for comparison to other airports as well and (2) about the need for a certification and verification program. Overall, airport representatives indicated moderate interest in using the rating system, with many saying that their interest depends on how the rating system is to be used and how well it addresses their existing questions and concerns. Several airport representatives said that their likely use would depend on whether the rating system is launched for internal or external purposes. Airport representatives were fairly divided in this respect; some liked the idea of comparing with or benchmarking against other airports, while others strongly preferred that the tool be used for internal purposes. The stakeholder outreach effort also directly engaged stakeholders on the topic of certification and verification. The research team found that, as with the rating system as a whole, the responses differed based on whether the airport representatives believed the rating system would be used for internal decision-making purposes or for external uses such as public relations. Many preferred the idea of using the rating system as an internal guide and believed that first-party certifica- tion and verification would be appropriate for these purposes. If the scoring were intended for external use, however, they believed third-party verification should be required for credibility, and anticipated that this could be cost-prohibitive. A few airport representatives expressed interest in ways to gain the credibility of third-party verification without incurring prohibitive costs, such A. Incorporate Elements of Existing Rating Systems B. Include a Points- Based Scoring Framework C. Adhere to the EONS Sustainability Framework D. Recognize Airport-Wide Sustainability Performance E. Flexible for Airports of Different Sizes & Geographies Prototype Rating System Yes Yes Yes Yes Yes Envision™ Yes Yes Yes No Yes (Focus on utilities/ infrastructure) LEED No Yes Main focus on Environmental No Yes (Focus on buildings) CDI SAM Yes Yes Yes No Yes (Focus on projects) ENERGY STAR No Yes No No Yes (Focus on buildings) Table 4-8. Comparison of representative rating systems against design specifications.

72 Prototype Airport Sustainability Rating System—Characteristics, Viability, and Implementation Options as having verification funded through external organizations or requiring verification updates infrequently (e.g., every few years rather than annually). Summary of Viability Conclusions The conclusion of the research team is that an airport sustainability rating system, complete with a certification and verification program, is viable in that (1) a defined user group exists and (2) the Prototype Rating System addresses the stakeholder’s design specifications whereas other existing rating systems do not address all design specifications. The costs of administration and governance would vary, however, based on the robustness of the certification and verification program. The implementation options for a certification and verification program could range from simply releasing the rating system as a Best Practices and Metrics Manual that airports could use internally to evaluate sustainability performance, to coupling the rating system with a robust independent certification and verification program that involves external certification and verification parties and procedures. Provided that a partner organization and the funds to support maintaining the governance and related certification services can be found, the eventual hosting institution would likely be the best candidate to make decisions about the certification and verification program. In the interim, however, if the industry determines that the goal of the rating system should be to serve as a universal resource to as many airports as possible, then a self-certification rating system may be better suited to focus on the universal benefits to all airports through a functional and flexible self-rating system. Adopting this option would establish the framework for ongoing rating system maintenance and provide the ability for airports to self-certify. The initial admin- istration and governance costs would likely be under $0.5 million without dedicated employees, office resources, or independent third-party certification. Ongoing operational costs could be below $100,000 per year. Beyond self-certification, the ability to benchmark performance against other airports would become secondary, and a robust certification and verification system is less critical, if not entirely unnecessary. The cost and level of effort to establish the benchmarking capability along with independent certification and verification institutions might not be warranted given a limited ability to compare across airports of different sizes, types, and locations, and given the likelihood of a broad spectrum of airports adopting the system. At this juncture, the effort may be best served initially by developing a self-certification approach, pending industry concurrence. A large, critical mass of participant airports of each type would then be necessary to overcome the likely functional and financial challenges to obtain the more extensive level of implementation. The Prototype Rating System would allow internal reviews of sustainability by airports at first, but the framework could also support external comparisons in the future, if desired by the airport community. 4.5 Potential Next Steps for the Airport Sustainability Rating System Figure 4-15 presents the development phases for completion of a functional draft Airport Sustainability Rating System (Draft Airport Sustainability Rating System). ACRP Report 119 concludes Phase II of the development process covered by the scope of work for ACRP Proj- ect 02-28, including the preparation of a Prototype Rating System. Any progress beyond Phase II would be conducted only after the airport community determines whether it is appropriate to continue developing the Airport Sustainability Rating System.

Development of Prototype Rating System 73 Phases I & II (Prototype Rating System Development). These now-completed phases involved preparing draft and final versions of the Prototype Rating System. Before moving ahead, the airport community will need to determine if it is appropriate to prepare a functional Draft Airport Sustainability Rating System (Draft Rating System) for testing through a pilot study featuring a diverse range of U.S. airports. Potential Phase III (Draft Rating System and Pilot). This potential phase would consist of preparing a functional Draft Rating System that would include a Draft User Guide and scoring framework and would assign proposed points to each of the activities. At the conclusion of this future work, the Draft Rating System could be piloted at a select set of airports. A potential work plan for Phase III appears in Appendix F. Potential Phase IV (Finalize and Release Airport Sustainability Rating System). Once the lessons learned from the pilot programs are captured, the Draft Rating System could be revised to create a fully formed, final rating system. Finalizing the rating system would likely require revising the scope of some activities, perhaps by adding activities identified through the pilot and likely by recalibrating the proposed weighted point scores assigned to each activity. The com- pleted rating system would require a hosting organization and sizable funding resources. Perhaps the most likely candidate for assuming governance responsibilities would be an airport trade association. An airport-industry organization could adopt and govern the final Airport Sustain- ability Rating System, hiring staff as needed to support the release and ongoing management of the system. This hosting group would need to establish advisory committees and mechanisms to both communicate and receive feedback from airport stakeholders. (More details on possible administration and implementation are in the “Rating System Development and Implementa- tion Options” section of this chapter.) Continued stakeholder involvement during the development of the Draft Rating System would help the airport community make a determination as to whether the rating system is Source: ICF 2013 Figure 4-15. Airport Sustainability Rating System development phases.

74 Prototype Airport Sustainability Rating System—Characteristics, Viability, and Implementation Options primarily for internal or external use. Successful ratings systems often first deploy a beta test by recruiting willing participants to test the system and identify the attributes that work and places where improvements are necessary. Once these pilot efforts have been assessed, the initial rating system is refined and rolled out to the broader industry. A pilot implementation of the Draft Rating System conducted at airports between potential Phases III and IV (see Figure 4-15) would serve as this beta test and would help determine the manner in which the final rating system should be deployed, allowing the industry to determine: • If the rating system is best used internally or for external comparison, which will drive decisions regarding the robustness of the certification and verification program. • If sufficient interest exists among U.S. airports to use the rating system. • If an organization exists that is willing to adopt the rating system and provide for ongoing administration and governance. 4.6 Conclusions This chapter presented a Prototype Rating System—or proof of concept—for the potential development of a Draft Airport Sustainability Rating System. The Prototype Rating System con- sists of the rating system structural components, illustrations of how they collectively support a rating system framework, a scoring framework, and a set of 50 sustainability activities grouped into 8 sustainability categories. The components and rating system structure are further illustrated by five sustainability activity descriptions that accompany this chapter and an annotated User Guide outline. Future potential work could include completion of descriptions for the remaining sustainability activities and incorporate these, as well as other guidance, into a final User Guide. When complete, the Airport Sustainability Rating System could assess airport-wide sustain- ability; provide airports with a resource for setting goals, objectives, and targets; and enable airports to evaluate continued sustainability performance over time. It would provide airports with a framework for categorizing and evaluating sustainability activities as well as insight into the operations, management activities, and infrastructure that support sustainability. The com- pleted rating system could also give airports a mechanism to take a snapshot of sustainabil- ity performance against which future performance can be evaluated. Through emphasis on documentation, the rating system would also aid airports in continuing measurement, support internal verification, and set the stage for third-party verification if and when airports choose to pursue it independently or it is incorporated as a rating system requirement. Additionally, the rating system would provide a common language for airports to describe, evaluate, and promote sustainability performance, internally and with the public.