CONCRETE VS. TAILPIPES: THE IMPORTANCE OF BOTH EMBODIED CARBON AND VEHICLE EMISSIONS IN THE CARBON FOOTPRINT OF DEDICATED TRUCK LANES ON I-70

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1 CONCRETE VS. TAILPIPES: THE IMPORTANCE OF BOTH EMBODIED CARBON AND VEHICLE EMISSIONS IN THE CARBON FOOTPRINT OF DEDICATED TRUCK LANES ON I-70 Vincent L. Bernardin, Jr., Ph.D. Bernardin, Lochmueller & Associates, Inc Vogel Road Evansville, IN Ph: Fax: Michael Grovak Bernardin, Lochmueller & Associates, Inc. P. O. Box 403 Brookston, IN Ph: Roberto Miquel Wilbur Smith Associates 5400 Glenwood Avenue, Suite 300 Raleigh, NC Ph: Submitted: November 15, ,506 Words, 4 Tables, 3 Figures

2 ABSTRACT This paper presents the methodology and results of developing a carbon footprint from a feasibility study of adding dedicated truck lanes to I-70 in Ohio, Indiana, Illinois and Missouri. It provides a complete method for carbon accounting in roadway infrastructure projects by integrating both greenhouse gases from vehicle emissions and embodied carbon from the construction and maintenance of the facility. The EPA s new MOVES model was used to estimate vehicle emissions, with off-model adjustments for hypothetical higher productivity vehicles (longer or heavier trucks). Embodied carbon was estimated per unit of construction activity/material based on the quantities in the construction cost estimates. The results confirmed the importance of a holistic approach that incorporates both vehicle emissions and construction and maintenance. For some scenarios, embodied carbon from construction and maintenance offset operational benefits from congestion relief. In other scenarios, especially with allowances for higher productivity vehicles (such as longer doubles or triples), decreases in vehicle emissions far outweighed emissions from construction and maintenance. Under the proper circumstances, dedicated truck lanes could be an infrastructure solution which decreases the carbon footprint of freight transportation, but a true reckoning of their net carbon impact can only be given by incorporating embodied carbon.

3 INTRODUCTION Increased concern regarding global climate change has led to new efforts to account for greenhouse gases in the evaluation and planning of highway infrastructure projects. Given the lack of regulatory statutes for carbon dioxide similar to those for criterion pollutants established under the Clean Air Act, in practice estimates of carbon footprints for highway infrastructure projects have been developed based on overly simplistic methodologies. For example, until the release of the United States Environmental Protection Agency s (EPA) new MOVES model in 2010, the EPA s own official emissions factor model, MOBILE6, did not even relate carbon dioxide emissions rates to vehicle speeds, despite the strong link between emissions rates and vehicle operating modes. A noteworthy methodological deficiency of carbon accounting for transportation infrastructure has been that it has almost exclusively considered carbon dioxide emissions from vehicle operations without regard for the emissions impact of constructing and maintaining the infrastructure itself. While the importance of a life-cycle perspective on costs is becoming increasingly common, this holistic accounting perspective including construction-related emissions has not been considered for greenhouse gas emissions. There have been a few exceptions, such as very high level conceptual evaluations of adding general purpose freeway lanes that incorporated construction and maintenance as well as operations (1). Others have advocated for the inclusion of infrastructure and supply chain considerations in the assessment of passenger transportation projects (2), proposed more holistic high level evaluation systems (3) and shown how important they can be in evaluating freight policies such as specific proposals for higher productivity vehicles (HPVs) (4). However, the only previous research on the air quality impacts of dedicated truck lanes (5) evaluated only changes in vehicle emissions without consideration of the carbon footprint for the infrastructure itself. Other evaluations of freight transportation (6) similarly neglect embodied carbon in infrastructure; embodied infrastructure carbon was not even mentioned in a recent synthesis of carbon accounting tools for freight (7). This paper presents the application of a new, more complete methodology for developing a carbon footprint from a real-world feasibility study (8) for proposed dedicated truck lanes (DTLs) on Interstate 70 (I-70) through Ohio, Indiana, Illinois and Missouri studied as a part of the Federal Highway Administration s Corridors of the Futures program. It is believed to be one of, if not the first planning application to incorporate both embodied carbon from construction and maintenance with vehicle emissions to create a comprehensive picture of the carbon footprint of alternative scenarios. The analysis included vehicle emissions modeling using the EPA s new MOVES model with a component unit-based approach to embodied carbon. Unitbased carbon accounting is typical in building construction, but still a relatively new application to highway construction. The results of the analysis demonstrate the importance of incorporating both elements in the carbon footprint. A carbon footprint for highways based on vehicle emissions alone could produce a skewed picture, particularly of carbon neutrality. Forecasts of net carbon emissions were particularly sensitive to the operating characteristics of different alternatives. Further, the results showed that for the case of the I-70 truck lanes studied, reductions in carbon emissions from vehicles can more than offset the embodied carbon from constructing and maintaining these lanes if HPVs are allowed on these lanes. These findings are important for two reasons. First, they help to understand the environmental implications of building truck-only lanes and related policies allowing HPVs.

4 Second, the results of this study also have implications for evaluating the environmental impacts of highway infrastructure in general, not only DTLs. Although truck lanes are considered here, the analysis illustrates the importance of evaluating both vehicle emissions and embodied carbon in developing carbon footprints for highway projects FIGURE 1 The I-70 Dedicated Truck Lanes Corridor I-70 DEDICATED TRUCK LANES This study was conducted as part of a larger feasibility study of dedicated truck lanes on I-70. The feasibility study describes itself in this way (8): The I-70 corridor is a key component of the freight supply chain connecting Missouri, Illinois, Indiana and Ohio to each other and to national and global markets. This interstate route and the water ports, airports, rail ways and intersecting roadways connected to it are impacted by continued growth in freight volumes driven by expanding national and international trade, growing populations and rising consumer demand for goods. Increasing congestion, capacity constraints, concerns about safety and potential loss in economic competitiveness are impacts facing the I-70 corridor and other interstate corridors and intermodal facilities connecting to it. The I-70 Dedicated Truck Lane Feasibility Study is the first system-wide evaluation of a single specific freight-focused solution to the congestion, capacity, safety and economic concerns facing the I-70 corridor today and into the future. The two-phased study was conducted by the I-70 Corridor Coalition, whose members include the state departments of transportation (DOTs) of Missouri, Illinois, Indiana and Ohio, as well as the Federal Highway Administration (FHWA). The study evaluated one potential solution that crosses jurisdictional boundaries and public and private interests. The study s key findings can be used by the Coalition and the FHWA to invest in DTLs as an efficient and sustainable long term solution for the corridor. The study process and analysis also

5 can provide FHWA, state DOTs and other multi-state /corridor coalitions, with an approach, data and information for evaluating the potential feasibility of DTLs on other interstate corridors. A carbon footprint was included as part of the feasibility study to better understand the environmental impacts of dedicated truck lanes in relation to other costs and benefits (such as existing safety and significant congestion issues). The carbon footprint included vehicle emissions calculations for three different I-70 DTL scenarios and a comparison to a no-build scenario. The scenarios included: Scenario 1 (No-Build): Only ongoing maintenance of the I-70 Corridor occurs. Scenario 3A: Two DTLs in each direction along the rural sections of the I-70 Corridor and two DTLs in each direction following bypasses around the urban areas. Scenario 3B: Identical to Scenario 3A in general design, but allows for HPVs along the entire corridor. Scenario 4: Two DTLs in each direction along the rural sections of the I-70 Corridor, one DTL in each direction through the urban areas, HPVs along the entire corridor. Technology improvements allow for increase lane use efficiency, allowing DTL construction in urban areas to be reduced to one lane. Construction for the DTL Scenarios was assumed to occur between 2020 and Major rehabilitation activities were assumed to occur between 2035 and 2099, and reconstruction activities between 2060 and Emissions activities associated with major rehabilitation and reconstruction activities are considered in this analysis. The carbon footprint of these four scenarios is evaluated in the following two sections. The next section addresses carbon emissions from vehicles while the following section examines embodied carbon from construction and maintenance activities. TRAFFIC AND VEHICULAR CARBON EMISSIONS Detailed traffic forecasts for the I-70 corridor, including hourly volumes and speeds by segment for both passenger vehicles (autos) and commercial vehicles (trucks) were developed using spreadsheet models that combined data on current traffic conditions, observed historic growth rates and information on diversion from national freight models. Hourly traffic distributions were based on actual permanent count station data on I-70 in both Indiana and Missouri. Speeds were developed based on relationships with traffic density from the Highway Capacity Manual (9). Several different travel demand forecasting models were applied to develop growth rates for the analysis horizon. Outside of the I-70 corridor a national freight model was calibrated for the feasibility study and provided forecasts of daily truck volumes. However, the model did not provide the speed data necessary for emissions modeling. Therefore, hourly volume and speed profiles for various years and functional classifications of roadway were developed using the Indiana Statewide Travel Demand Model (ISTDM). These hourly volume and speed profiles were applied to the national freight model data to provide detailed traffic data needed for emissions modeling. The national freight model for trucks (rather just the corridor model) was used because the impacts and benefits of the I-70 DTLs go beyond the I-70 corridor. Both a survey of truckers

6 and the model reflected that any improvement made to traffic for trucks along I-70 would draw some longer truck trips from other interstate corridors, such as I-80/I-90 or I-64, to the I-70 corridor. An I-70 corridor-only evaluation would potentially show an increase in truck traffic and an increase in emissions throughout the entire I-70 corridor due to diversion to I-70. However, a national evaluation would show an overall decrease in emissions, as trucks divert from other facilities. 1 The analysis predicts that emission reductions in other corridors outweigh emission increases in the I-70 corridor. This is due to operational efficiencies of the DTLs from reduced congestion and (in certain scenarios) allowance of HPVs. Although travel time along the I-70 corridor will be improved for auto traffic, this study assumes that the construction of DTLs attracts only trucks (and not autos) from other interstate corridors. Therefore, reductions in auto emissions in other corridors are conservatively assumed to be negligible. Auto emissions were evaluated within the I-70 corridor only. The traffic forecasting methodology was limited by the scope of the project, which did not include development of a corridor-wide travel demand model that incorporated both cars as well as trucks. Without a travel demand model, it was difficult to address induced demand for passenger travel on the corridor, and the oversimplification of this dimension of traffic is a significant limitation of this analysis. However, the impacts of dedicated truck lanes (both in terms of traffic and emissions) are much greater for trucks than for cars. Therefore, the simplistic treatment of auto traffic demand in a spreadsheet model does not obscure the fundamental results CO2 (g/mi) Speed (mph) Auto - Urban Auto - Rural Truck - Urban Truck - Rural FIGURE 2 MOVES CO 2 Vehicle Running Emissions Rates by Speed for I-70 1 The feasibility study found there was fairly little potential for diversion to/from rail given the commodities and trip lengths in the corridor, based upon FHWA s Freight Analysis Framework.

7 Running emission rates were calculated using MOVES2010a, using national scale runs for representative urban and rural counties throughout the corridor. MOVES is a tool created by the EPA for estimating emissions from highway vehicles. Non-running emissions (starts, evaporative soak emissions, etc.) were assumed to be constant across all scenarios. Running emissions rates were developed by year, speed and vehicle class. These were aggregated from MOVES 13 vehicle classes into rates for cars and standard trucks and applied to the traffic data by speed. The MOVES model incorporates anticipated EPA improvements in renewable fuel standards and fuel economy standards. Off-model adjustments were made to adjust truck emissions rates for HPVs. The CO 2 2 emissions rates from MOVES are displayed in Figure 2. Since CO 2 emissions are driven by fuel consumption, the emissions are highest at very low speeds experienced under congested conditions for which fuel consumption is highest and decrease until they more or less stabilize under uncongested conditions. Light vehicle or auto emissions varied little between urban and rural areas when controlling for speed or congestion, but truck emissions were slightly higher in rural areas because the mix of trucks on I-70 in rural areas is skewed more toward larger/heavier vehicles. The urban truck mix includes more lighter, delivery-oriented vehicles. Assumptions regarding HPVs were critical in the analysis. In 2008, the American Transportation Research Institute (ATRI) and its Western Highway Institute, in cooperation with Cummins, Inc., prepared the Energy Emissions Impacts of Operating Higher Productivity Vehicles Update: 2008 (10). The report modeled and compared emissions from typical five-axle tractor-semitrailers (a three-axle sleeper cab and tandem-axle 53-foot semitrailer) and double configuration tractor-semitrailer (a two-axle day cab, two 28-foot single-axle trailers, and a single-axle dolly connecting the two trailers), with four different types of HPVs. Based on the ATRI s modeling, HPVs analyzed in the study (for weight-limited operations) had per vehicle payload weight increases ranging from four to 88 percent. For cube-limited operations, per vehicle payload weight increases ranged from 42 to 80 percent through the addition of trailers and dollies. As payload weight increases fuel economy in miles-per-gallon decreases. The study found that weight-limited HPVs had a fuel economy decrease of 11 to 30 percent and cubelimited HPVs had a fuel economy decrease of 10 to 22 percent. For the purposes of the I-70 DTL analysis, HPVs fuel economy decreases were assumed to be a conservative 20 percent overall based on this report. Based on considerations of the length of truck trips, the commodities being carried, the type of trucking operations in the corridor, the study ultimately assumed that given the allowance of HPVs would result in 18% HPVs on the corridor with 30% less typical five-axle tractor-semitrailer trucks. Even though fuel economy decreases result in greater emissions per vehicle-trip, these were more than offset by significant reductions in the number of vehicle trips due to the use of HPVs. The use of HPVs also reduced congestion, which leads to higher speeds and reduced emissions. Forecast carbon dioxide emissions for three different DTL scenarios were compared to the no-build Scenario 1 for 2025 and In 2025, only about a third of the DTLs were assumed to be completed throughout the four state corridor; by 2045, the DTLs were assumed to be complete across the entire 800 mile corridor. Table 1 shows the difference in tons per year of carbon dioxide compared to the No-Build Scenario for year 2025 and Vehicle emissions are given as CO2 quantities and do not include well-to-pump emissions, since the CO 2 e calculator and wellto-pump functionality in the MOVES2010a model were disabled and not working properly, respectively. The constructionrelated estimates provided later in this paper include CO 2 equivalents for methane (CH 4 ) and nitrous oxide (N 2 O). The emissions associated with methane and nitrous oxide are about 1% of CO 2 equivalents for PCCP production and about 5% of CO 2 equivalents for HMA production.

8 TABLE 1 Change (vs. No-Build) in CO 2 Emissions from Vehicles by Scenario (tons) Scenario 3A Scenario 3B Scenario , , , , ,277, ,233,077.4 In 2025, when DTLs are present through only a portion of the corridor, Scenarios 3B and 4 show some modest decreases in CO 2, but Scenario 3A shows an increase. When DTLs are present throughout the corridor in 2045 all three DTL scenarios show reductions in carbon emissions as emissions savings from the DTLs increase over time, both due to increased utilization as they are completed and worsening congestion on competing facilities. Consistently, however, in both years, Scenarios 3B and 4 show substantially less CO 2 due to their assumed allowance of HPVs. EMBODIED CARBON Estimates of embodied carbon, or CO 2 emitted in the process of constructing and maintaining the facility, were developed based on quantities of materials and activities required, as is becoming common in carbon footprints of structures. Construction cost estimates already developed for the I-70 DTLs included construction quantities for major construction inputs for each scenario (including the no-build). Quantity estimates provided for each scenario included: Cubic yards of concrete Tons of asphalt Cubic yards of base aggregate Cubic yards of earthwork The construction estimates also provided estimates by seven future time periods. These included estimates for new construction, rehabilitation, and reconstruction (by scenario) for these seven time periods: Scenario 1 provides for reconstruction activities between 2020 and 2044, and rehabilitation activities between 2035 and Scenarios 3A, 3B and 4 provide for construction activities between 2020 and 2024, rehabilitation activities between 2035 and 2099, and reconstruction activities between 2060 and Published sources provided emissions rates associated with the production and construction use of the construction materials listed above. Emissions rates for concrete, asphalt and base aggregate were taken from a report prepared by the Athena Institute, prepared for the

9 Cement Association of Canada 3 (11). Canadian unit emissions were used in part due to the lack of authoritative unit emissions for the United States. 4 The emissions rates in the Athena Institute report provided regionally-specific estimates of the primary energy and greenhouse gas emissions associated with the production and transportation of a unit (cubic meter) of concrete, asphalt, and base aggregate. 5 The executive summary of the report states, The primary energy estimates included the upstream or precombustion energy necessary to extract, process or manufacture and transport primary fuels to their point of use. In the case of electricity generation, the study also accounts for regional generation efficiency by fuel type and transmission line losses to estimate the net primary energy and greenhouse gas emissions associated with delivering a unit of electricity. 6 A CO 2 equivalence was used to convert other greenhouse gas emissions (CH 4 and N 2 O) to units of CO 2, using an equivalence method developed by the International Panel on Climate Change. For each of these primary inputs, the report calculated a range of CO 2 e embedded emissions, corresponding to typical Canadian inputs, as well as inputs specific to the provinces of Quebec and Ontario. These embedded emissions are shown in Tables 3.2 through 3.4 of the report. The embedded CO 2 e emissions were converted to English units corresponding to the construction input estimates in the I-70 analysis. The estimates of embedded carbon in the construction component quantities were calculated by applying the range of values of embedded CO 2 e emissions from the Athena Institute report. Application of these emissions factors assumes that production and construction practices in Canada are representative of those in the Midwestern United States. This is a reasonable assumption, in particular given that a range of values was calculated. For the inputs with the large majority of embedded CO 2 e emissions (concrete and asphalt) the high-end of the emissions factors were 5 to 8% greater than the lowend values. To compute earthwork-related emissions, detailed emissions factors for a wide range of construction equipment were taken from a recent report by the California Department of Water Resources (12). Earthwork-related emissions were calculated assuming that a full complement 3 The engineering analysis for this project assumes that approximately 90% of the paving materials are asphalt (HMA) and about 10% are concrete (PCCP). In this regard, basing the emissions analysis on a report prepared for the Cement Association of Canada may be characterized as using conservative assumptions. 4 American sources consulted to attempt to identify project-level factors for GHG emissions in construction included New York State DOT. Documentation located on its website ( We were able to identify only analyses referencing the Athena Institute Report (e.g., Quantifying the Energy and Environmental Effects of Using Recycled Asphalt and Recycled Concrete for Pavement Construction Phase I Final Report, August 2009). We were unable to identify any methodologies which would supplement the Athena Institute Report. The USEPA also publishes reports Inventory of U.S. Greenhouse Gas Emissions and Sinks, most recently updated in April This report estimates the total GHG emissions in the United States related to cement production; however, it does not furnish information relating GHG emissions to actual quantities of PCCP used in construction. 5 The engineering analysis for this study assumed that approximately 90% of paving materials were HMA, and 10% were PCCP. Case studies presented in the Athena institute report considered emissions associated with rebar used in concrete pavement, and determined that those GHG emissions were about 2 3% of those associated with the PCCP. For this study, emissions associated with rebar were regarded as negligible. The engineering analysis did not provide estimates of quantities of structural steel; cost estimates were based upon general assumptions about structure size and type. Estimates of emissions associated with structural steel are not included. In addition, a significant proportion of electricity in Ontario and Quebec is generated from hydroelectric and nuclear sources. Up to 10 12% of primary energy used in cement production is electricity (Table 5, p. B-6). Given the low percentage of PCCP used for paving materials, differences in methods of electric power generation in Canada vs. the United States were regarded as negligible. 6 These estimates include GHG emissions generated in cement production.

10 of earth-moving equipment would allow about 50,000 cubic yards of earthmoving activity per week. 7 Tables 2 and 3 provide the calculations of emissions related to construction components for Alternative 4. TABLE 2 - CO 2 e Emissions - Build Scenario 4 with Dedicated Truck Lanes - Urban Areas - Construction (2020 to 2044) Low High Concrete-related emissions (lbs) 208,050, ,590,000 Asphalt-related emissions (lbs) 856,520, ,210,000 Base-related emissions (lbs) 92,060, ,160,000 Earthwork-related emissions (lbs) 38,050,000 38,050,000 Total Emissions (lbs) 1,194,680,000 1,291,010,000 Total Emissions (tons) 597, ,505 TABLE 3 - Difference in Total Life-Cycle CO 2 e Emissions by Source vs. No-Build (2020 to 2044) Low High Concrete-related emissions (lbs) 643,440, ,620,000 Asphalt-related emissions (lbs) 3,508,950,000 3,692,040,000 Base-related emissions (lbs) 382,420, ,110,000 Earthwork-related emissions (lbs) 103,560, ,560,000 Total Emissions (lbs) 4,638,370,000 5,018,330,000 Total Emissions (tons) 2,319,185 2,509,165 Embedded CO 2 e emissions were calculated separately for urban and rural areas. They also were calculated separately for construction, reconstruction, and rehabilitation activities. For construction and reconstruction activities, 87 88% of the carbon emissions were associated with pavement (concrete and asphalt), 10 11% with base and subgrade, and 2 3% with earthmoving activities. For rehabilitation activities, all emissions were associated with pavement. For the three build alternatives, the variations in embedded carbon emissions were minor. Table 4 shows the total facility-related embedded emissions for the three build alternatives These estimates reflected transportation of fill materials offsite. Since offsite activities represent a small portion of earthwork activities, and GHG emissions associated with earthwork were 2 3% of total emissions, no sensitivity analysis was conducted regarding distances to offsite borrow locations.

11 TABLE 4 - Total Life-Cycle CO 2 e Emissions (2020 to 2099) Associated with Construction, Reconstruction and Rehabilitation Activities (Tons) 8 Low High Scenario 3A 5,759,730 6,203,115 Scenario 3B 5,824,545 6,275,390 Scenario 4 5,666,660 6,106,205 FINAL RESULTS AND CONCLUSIONS The two estimates of CO 2 from vehicle operations and embodied in the facility from its construction and maintenance were combined to present the net life-cycle carbon impact of the build scenarios. Vehicle emissions from 2025 and 2045 were extrapolated to produce an annual stream of emissions using the conservative assumption that annual emissions savings would stabilize shortly after Scenario 3A Scenario 3B Scenario 4 0 CO2 (1,000's of tons) Vehicle Emissions Construction and Maintenance Carbon Net Change FIGURE 3 Net Life-Cycle Change in Carbon Dioxide vs. No Build 8 Includes emissions quantities associated with reconstruction of facility occurring between 2060 and 2099, as well as major rehabilitation of facilities occurring between 2035 and 2099.

12 The result, illustrated in Figure 3, was a different conclusion than either analysis would have yielded alone. The vehicle emissions showed that by 2045 scenarios 3B and 4, which allowed HPVs, result in significant overall emissions reductions. The embedded carbon analysis showed little difference among the three scenarios. Only when the two analyses were combined in a holistic life-cycle accounting framework did it become clear that scenarios 3B and 4 offered significant net decreases in carbon emissions. Scenario 3A failed to achieve carbon neutrality as its minor operational benefits could not offset the impact of constructing and maintaining the facility. Given the long analysis period (80 years), the precision of the out-year estimates is somewhat speculative; emissions savings were constant after However, the significant overall emissions reductions associated with scenarios 3B and 4 are clearly valid. The practical result for the study of I-70 DTLs is that the project presents a green infrastructure solution with decreased carbon emissions from both congestion relief and the allowance of HPVs. The level of benefits will depend significantly on the precise nature of these policies, such as whether HPVs would be allowed to also operate on facilities within a buffer around I-70 or only on the DTLs themselves. More generally, this case study provides a clear illustration that the carbon neutrality of highway infrastructure improvements must properly be evaluated by considering both vehicle emissions and the construction and maintenance of the facility. Failure to consider either skews fundamental results, such as whether a project results in a net increase or decrease in carbon. ACKNOWLEDGEMENT The authors gratefully acknowledge the support of the Federal Highway Administration s Corridors of the Future program, together with the Ohio, Indiana, Illinois and Missouri state departments of transportation under the leadership of Keith Bucklew. The authors also would like to acknowledge the assistance of the American Transportation Research Institute in developing assumptions regarding HPV utilization of I-70 DTLs. REFERENCES 1. Williams-Derry, C. Increases in greenhouse-gas emissions from highway-widening projects. Sightline Institute, Seattle, WA, October Chester, M. and A. Horvath. Environmental Assessment of Passenger Transportation Should Include Infrastructure and Supply Chains. Environmental Research Letters, Vol. 4, 2009, pp Samberg, S., A. Bassok and S. Holman. Sustainable Transportation Evaluation Method: Toward a Comprehensive Approach. Presented at the 90th Annual Meeting of the Transportation Research Board, National Research Council, Washington, D.C., Sathaye, N., A. Horvath and S. Madanat. Unintended impacts of increased truck loads onpavement supply chain emissions. Transportation Research, Part A, Vol. 44, No. 1, 2010, pp Chu, H-S. and M. Meyer. Methodology for assessing emission reduction of truck-only toll lanes. Energy Policy, Vol. 37, No. 8, 2009, pp Farzaneh, M., J. Lee, J. Villa and J. Zietsman. Corridor-Level Air Quality Analysis of Freight Movement: A North American Case Study. Presented at the 90th Annual

13 Meeting of the Transportation Research Board, National Research Council, Washington, D.C., Tunnell, M. and K. Fender. A Synthesis of Carbon Accounting Tools with Applicability to the Trucking Industry. American Transportation Research Institute, Arlington, VA, June I-70 Dedicated Truck Lanes Feasibility Study Phase 2 Final Report. Indiana Department of Transportation, Indianapolis, IN, Forthcoming. 9. Highway Capacity Manual. Transportation Research Board of the National Academies, Washington, D.C., Tunnell, M. Energy Emissions Impacts of Operating Higher Productivity Vehicles Update: American Transportation Research Institute, Arlington, VA, March Meil, J. A Life Cycle Perspective on Concrete and Asphalt Roadways: Embodied Primary Energy and Global Warming Potential. Athena Institute. Chester Springs PA Erickson, C. Initial Study DWR Oroville Operations & Maintenance Center Garage Shop and Temporary Office Building. California Department of Water Resources, Sacrament CA