Transportation is the second largest source of Greenhouse Gas (GHG) emissions in the United States. The challenge is to reduce GHG emissions through the use of more fuel efficient vehicles, reduction of total miles driven, as well as the inclusion of planning strategies in transportation systems.

The New Jersey Global Warming Response Act, enacted in 2007, mandates reductions in greenhouse gas (GHG) emissions to 1990 levels by 2020, an approximately 20 percent reduction, followed by a further reduction of emissions to 80% below 2006 levels by 2050.

The legislation required several state agencies, including New Jersey Department of Transportation (NJDOT) to assess GHG emissions related to their operations and develop methods to meet and exceed the 2020 target reductions. To achieve this goal, NJDOT focused on assessing and monitoring GHG emissions of both its Capital Program and Operations. The purpose of this research project is to support this effort by focusing on effective monitoring of GHG emissions produced by Operations Maintenance activities and identifying solutions for GHG reduction.

The project evaluates emissions generated by vehicles, equipment, and materials used in maintenance operations projects by applying the life-cycle analysis approach. The literature review focuses on identifying the sources of data and methods for evaluating carbon potential of materials mostly used in highway maintenance projects, such as asphalt, concrete, and steel. The review is further expanded to identify potential methods and strategies that will help reduce GHG emissions of highway maintenance projects, focusing primarily on construction processes and aggregate industry, especially asphalt and bitumen. The emissions generated by vehicles and equipment also are analyzed, as are strategies for reducing related carbon emissions through the introduction of more fuel-efficient or hybrid engines and alternative fuels.

Based on methods developed in this study and the collected data, a decision-support software tool is being developed to guide NJDOT in monitoring and assessing alternatives for reduction of GHG emissions related to Operations Maintenance. Both the analysis framework and the decision-support tool will provide means for quantifying the effects of different strategies for reducing GHG emission, and will ultimately be useful in developing department-wide GHG emission reduction strategies.