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EPA Releases New Guidance for Quantifying and Using Emission Reductions from Best Workplaces for Commuters Programs in State Implementation Plans and Transportation Conformity Determinations

EPA420-F-07-064, October 2007
Download the PDF version of this fact sheet formatted for print. (3pp. 100KB, About PDF files)

The U.S. Environmental Protection Agency (EPA) has developed guidance for states and agencies that are involved in developing state implementation plans (SIPs) or transportation conformity determinations. This guidance explains how these agencies can incorporate emissions reductions resulting from changes in commuter trip behavior to their SIPs and transportation conformity determinations.

The guidance explains how providing a high level of commuter benefits, as defined by achievement of the Best Workplaces for Commuters (BWC) designation, can result in decreased commuter trips, leading to decreased emissions. It also provides information on using one of the tools available to quantify these reductions--a newly-revised, spreadsheet-based calculator called the COMMUTER model.

Best Workplaces for CommutersSM

BWC is a voluntary programs developed by EPA's Office of Transportation and Air Quality and now administered by the Center for Urban Transporation Research (CUTR), aimed at achieving measurable environmental benefits in a cost-effective way, without the need for regulation. Employers qualifying to be designated as BWC must offer excellent commuter benefits that meet the program's "National Standard of Excellence." Voluntary programs like BWC can reduce pollution and improve air quality through strategic partnerships with small and large businesses, citizen groups, industry, manufacturers, trade associations, and state and local governments.

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SIP and Transportation Conformity Determinations

Commuter benefit programs like BWC can offer quantifiable emission reductions. The guidance document describes the requirements for seeking emissions credit for BWC-related measures in SIPs and transportation conformity determinations. While various modeling methodologies for estimating the benefits of BWC-related measures are available, state and local agencies seeking reductions for SIPs or conformity should engage in a consultation process with EPA regarding appropriate methodologies.

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EPA has updated the COMMUTER model, first released in 2001, to assist worksite transportation coordinators and local planners in estimating the impacts of commuter programs like BWC. The 2005 revision interfaces with EPA's current MOBILE6.2 emission factor model and adds the capacity to estimate how a commuter benefit can impact particulate matter, air toxics emissions, and fuel use and costs. Running the model requires the user to provide information on the number of employees covered and the types of benefits offered to them. The COMMUTER model allows users to input local-specific travel data, and emissions factors based on a MOBILE6.2 run representing the area. The MOBILE6.2 look-up tables for emission factors in the COMMUTER model can be used to provide a preliminary estimate on what reductions are produced. If you choose to use the COMMUTER model to quantify emission reductions for SIP or transportation conformity purposes, you should use your own locally-generated MOBILE6.2 emission factors and local travel activity data to calculate emission reductions.

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Bundled Measures

The guidance "Incorporating Bundled Measures in a State Implementation Plan (SIP)" released in August 2005 describes an option for how BWC-related activities could be "bundled" with other voluntary measures for SIP purposes. In cases where many small employers in an area are implementing BWC-related activities, it may be appropriate to consult this guidance along with the Bundled Measures guidance to quantify and account for the expected emission reductions.

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For More Information

You can access the guidance, the COMMUTER model, and related documents on the Office of Transportation and Air Quality (OTAQ) Web site at: https://www.epa.gov/otaq/stateresources/policy/pag_transp.htm#cp.

For questions regarding this guidance:
Mary Walsh

For questions regarding BWC measures in transportation conformity determinations:
Meg Patulski

For questions regarding the COMMUTER model:
Erik Herzog

For more information about Best Workplaces for Commuters, visit www.bestworkplaces.org or send an email messat to info@bestworkplaces.org.

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