Transportation agencies across the nation are implementing a variety of measures to meet their environmental, economic, and social sustainability goals. Historically, quality management activities have contributed to the sustainability of transportation projects through quality assurance (QA) programs and quality control (QC) plans, which help improve performance, reduce the quantity of unacceptable product constructed and the associated environmental impacts of rework, increased materials use, and community impacts, among other benefits.
In recent years, green public procurement (GPP) initiatives have become increasingly of interest to agencies hoping to reduce the environmental impact of their infrastructure. GPP initiatives rely on construction materials environmental product declarations (EPDs) to communicate the environmental impacts of a material and to compare choices. Some agencies that have started to use some sustainability-related quality metrics (such as global warming potential, emissions, or gallons of water conserved). However, these metrics are not uniform and need to be expanded. Quality metrics could be established for EPD programs to support sustainable procurement for many materials. Although effectively supporting environmental improvements, there has been concern that PCRs and EPD programs, as currently developed and used by manufacturers, provide a range of comparability and harmonization across sectors. As a result, the information communicated by EPDs may not meet agency needs for comparing impacts and performance. The level of detail and extent of third-party verification also varies by EPD program. Agencies are interested in using EPDs to support GPP, but guidance to support their use to meet agency sustainability objectives is limited.
FHWA has been supporting work to improve both comparability and harmonization of EPDs. However, agencies still lack guidance on ways to implement strategies to support comparability and harmonization. In addition, there is also the issue of verification of EPD properties (such as when an EPD for a mixture indicates it incorporates a certain percentage of recycled material or supplementary cementitious material (SCM) in production), as the verification processes are not well established by most agencies. If a sustainable product is required or contractor selection is based on a proposed EPD during procurement, then agencies will need to verify that those products that are proposed to meet the EPD are actually incorporated into the project. For example, if an EPD is proposed that includes a percentage of a recycled material (such as recycled asphalt pavement (RAP), recycled concrete aggregate (RCA), recycled tire crumb rubber, or SCM), then the approved mixture designs should also require those same percentages and their use should be verified in production. QA programs currently allow such products provided they meet the current acceptance testing requirements, the material usage quantities (or percentages) as indicated on the EPDs are not currently being verified. Additionally, agencies need guidance on how to approach unacceptable materials. Currently, no guidance exists to support agencies in establishing and using QA and metrics as part of GPP to help meet their sustainability goals (e.g., is an agency getting the environmental benefits they are paying for). Guidance on benchmarks for environmental performance is also needed to assist agencies in establishing criteria for sustainable materials procurement.
Ultimately, harmonized PCRs and improved EPDs are needed to ensure accurate life cycle analyses of transportation projects. Research is needed to support harmonization of PCRs for the materials used in transportation construction. PCRs define the system boundaries, impact categories, and methodologies used for developing and using the EPD. Guidance to improve the consistency and comparability of EPDs for transportation materials is needed to support agencies in assessing tradeoffs and making decisions.
The objective of the research is to develop guidance to support agencies in establishing and using QA and metrics as part of GPP to help meet their sustainability goals. Identify potential future improvements in EPD programs, agency practices, or other areas to maximize the use and benefits from EPDs. Tasks could include:
1. Literature review of publications and specifications associated with EPDs and LCA with a focus on the role of QA in supporting these initiatives to include case studies in industries (such as energy and real estate) that have implemented GPP and EPDs.
2. Collect information from agencies regarding their sustainability goals, GPP, EPDs, and needs to support LCA (define). Emphasis should be placed on metrics that could be used from a quality standpoint to support these efforts, as well as needs that could be met by additional guidance, or by changes in EPD programs. The role of agencies in influencing EPD programs should also be documented; agencies that could serve as champions to implementation will be identified.
3. Identify existing practices used by transportation agencies and industry to support GPP, and related quality management.
4. Develop guidance to support agencies in establishing and using QA and metrics as part of GPP to help meet their sustainability goals.
Additional potential tasks include identifying further work by industry needed to support PCRs and EPDs to support LCAs. Anticipated topics include (a) EPDs coverage/scope to fully meet transportation agency needs, (b) implementation routes and scenarios (such as incentives, benchmarks, go/no-go scenarios, etc.) that are useful in supporting GPP, (c) requirements for third-party verification of EPDs, (d) benchmarks for environmental performance in materials procurement, (e) methods by which agencies can better influence EPD programs, (f) methods by which agencies can improve their verification process between the EPD and the as-constructed product, and (g) expected barriers and challenges to the implementation of EPDs.