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CHAPTER 12 Emissions and Cost Impacts Overview Purpose Port container drayage is widely recognized as a critical emissions and congestion issue for major container ports, rail intermodal terminals, and the surrounding communities. These issues can be addressed and quantified through use of an emissions and activity model-- EPA's SmartWay DrayFLEET--that accurately depicts drayage activity in terms of vehicle miles traveled (VMT), emissions, cost, and throughput, and can reliably reflect the impact of changing management practices, terminal operations, cargo volume, and diesel truck upgrades. The DrayFLEET Model, a User's Guide, and a complete report on development of the model are available on the following EPA SmartWay Web site at http://www.epa.gov/ otaq/smartway/transport/partner-resources/resources-drayage.htm and also offers infor- mation about selected drayage emissions reductions strategies, such as chassis pooling and diesel retrofits. Ports and terminals all fulfill the same basic functions, but do so in several different ways and in many detailed variations. DrayFLEET includes model options for all significant drayage func- tions at any port complex, even though those model options may be used rarely. The model includes the following: Drayage trips of all types to and from marine container terminals, for any reason; Drayage trips between rail intermodal terminals and marine terminals, and associated bobtail and chassis trips that may not begin or end at the port; and "Crosstown" trips to reposition empty import containers for export loads, to shift empty marine containers from rail terminals to depots, or to obtain empty containers from depots for export loads. The DrayFLEET Model therefore includes a number of trips and trip types that do not begin or end at port terminals but are necessary to support the overall port container flow. The model does not attempt to account for trips for servicing, fuel, and repair; side trips for meals, rest, or errands; and trips made on non-port assignments such as domestic rail inter- modal drayage. Because volumes vary from year to year and month to month while movement patterns tend to persist, the model relies primarily on pattern indicators and proportions to estimate drayage trips, times, and mileages. This approach facilitates forward-looking or "what if" analyses of drayage activity and emissions with growing cargo volumes. 88

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Emissions and Cost Impacts 89 Model Approach The model allows users to input data values typical of their port or terminal (such as annual TEU or distance to major customers) to create a base case activity and emissions estimate. The user can then make further input choices to create "what if" scenarios. DrayFLEET is distributed as a generic model for a hypothetical container port handling 2 million annual TEU. There are three basic steps to setting up the model for application to a specific port or terminal, as follows: 1. Input the port or terminal's specific base case default values, 2. Reset the default output values to create a port-specific base case, and 3. Create scenarios as required. The DrayFLEET Model incorporates an activity-based approach. Each significant drayage trip type or activity is assigned a time and distance value. That value may be a precise empirical mea- surement, a weighted average, or an industry rule of thumb, depending on the data available. The model takes the total container volume handled by the port or terminal in question and determines the volume and mix of drayage activities required or implied. The time and VMT for those activities are tallied to develop port or terminal total drayage minutes and VMT. For input to the emissions model, each activity time is divided into minutes by driving cycle component--idle, creep, transient, and cruise. Drayage time and miles also become inputs to the cost and capacity portions of the model. The drayage activity cycle is made up of idling, queuing/creeping, and driving in various combinations. The activity modeling approach includes several key features as follows: Port-specific or generic default values for every variable and input; Accommodation of user inputs that differ from defaults; A streamlined user "front end" to facilitate primary inputs and "what if" scenarios; An embedded flow chart of port-related container trips to account for all significant movements; Activity tally sheets to capture default or user-specified factors for over-the-road drayage, terminal trips, etc.; and Summary activity model outputs in minutes by duty cycle to serve as emissions model inputs. Figure 121 gives an overview of the model structure and the flow of information. USER PRIMARY PRIMARY INPUTS INPUTS WORKSHEET WORKSHEET USER INPUTS INPUTS OR PORT PORT /GENERIC /GENERIC CONTAINER CONTAINER DISTRIBUTION DISTRIBUTION DEFAULTS DEFAULTS OPTIONAL OPTIONAL DETAILED DRAYAGE DRAYAGE ACTIVITY ACTIVITY SHEETS SHEETS DETAILED INPUT INPUT FACTORS FACTORS PRIMARY PRIMARY OUTPUTS: OUTPUTS: DRAYAGE DRAYAGE VMT MINUTES MINUTES BY BY DUTY DUTY CYCLE EMISSIONS EMISSIONS MODEL MODEL Figure 121. DrayFLEET model structure.

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90 Truck Drayage Productivity Guide Input categories include the following: Port and terminal information (e.g., TEU, import/export balance); Default/scenario operational factors (e.g., transaction times); Management strategies (e.g., on-dock rail, automated gates); and Drayage tractor fleet and technologies (e.g., diesel engine retrofits). Outputs provided include the following: Activity outputs (e.g., trip legs and VMT); Duty cycle outputs (e.g., idle, creep, transient, and cruise minutes); and Comparison charts to illustrate changes from defaults. Figure 122 shows the primary inputs worksheet. This worksheet (shown in its entirety) has five sections covering key input values, port or terminal management initiatives, activity outputs, emissions and cost outputs, and a note section to identify the model application and scenario. For each of the primary inputs there is a default value and a scenario value. The model uses the default value unless it is superseded by a different user entry in the scenario columns. The key port and terminal inputs specify the overall volume and pattern of container movements. The generic model version offers the user convenient starting points to avoid having to input every variable. The user can replace other defaults with specific scenario information as available. Emissions Estimates DrayFLEET calculates emissions by combining the amount of time that trucks spend within var- ious modes of operation (idle, creep, transient, and cruise) with EPA emissions rate data specific SmartWay DrayFLEET Version 1.0 Primary Inputs & Outputs DrayFLEET Version 1.0d of 06/10/2008 Primary Inputs Default Scenario Port Port Terminal(s) Calendar Year 2007 2007 Scenario Annual TEU 2,000,000 2,000,000 Average TEU per Container 1.75 1.75 Inbound Share 50% 50% Inbound Empty Share 5% 5% Date Outbound Empty Share 25% 25% Rail Intermodal Share 25% 25% Activity Outputs Default Scenario Change % Change Marine Terminals Annual Activity Average Inbound Gate Queue Minutes 15 15 Number of Drayage Trip Legs 3,498,452 3,498,452 0 0.0% Average Marine Terminal Min. per Transaction 30 30 Drayage Trip Legs per Container 3.1 3.1 0.0 0.0% Rail Terminals Total Drayage VMT 65,706,753 65,706,753 0 0.0% Weighted Average Miles from Port 5 5 Drayage VMT per Container 57.5 57.5 0.0 0.0% Average Inbound Gate Queue Minutes 5 5 Fleet Required (FTE Tractors) 1,224 1,224 0 0.0% Average Rail Yard Min. per Transaction 15 15 Annual Duty Cycle Totals Container Depots Idle Hours 1,869,294 1,869,294 0 0.0% Weighted Average Miles from Port 2 2 Creep Hours 994,223 994,223 0 0.0% Share of Empties Stored at Depots 10% 10% Transient Hours 572,700 572,700 0 0.0% Container Shippers/Receivers Cruise Hours 1,506,026 1,506,026 0 0.0% Weighted Average Miles from Port 25 25 Total Drayage Hours 4,942,243 4,942,243 0 0.0% Weighted Average Crosstown Trip Miles 10 10 Drayage Hours per Container 4.3 4.3 0.0 0.0% Cost Factors Average Drayage Labor Cost per Hour $ 12.00 $ 12.00 Emissions Outputs Default Scenario Change % Change Average Diesel Fuel Price per Gallon $ 4.00 $ 4.00 Pollutant (annual tons) HC 53 53 0.00 0.0% Initiative Inputs Default Scenario CO 298 298 0.00 0.0% Port/Terminal Initiatives NOx 1,108 1,108 0.00 0.0% Stacked Terminal (% stacked) 0% 0% PM10 37 37 0.00 0.0% On-Dock Rail (% of rail on-dock) 0% 0% PM2.5 31 31 0.00 0.0% Automated Gates (% of gate transactions) 0% 0% CO2 88,497 88,497 0 0.0% Extended Gate Hours (% off-peak, 50% max) 0% 0% Fuel Use and Total Cost Container Info System (% used) 0% 0% Fuel - Gallons 7,909,626 7,909,626 0.0 0.0% Virtual Container Yard (% available) 0% 0% Total Drayage Cost $ 159,451,797 $ 159,451,797 $ - 0.0% Neutral Chassis Pool (% used) 0% 0% Drayage Cost per Container $ 140 $ 140 $ - 0.0% Figure 122. Primary inputs worksheet.

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Emissions and Cost Impacts 91 to those operating modes for a given fleet age distribution. Loaded and empty emissions are calcu- lated separately. The emissions rate data are already part of the DrayFLEET Model and the amount of time spent within each mode comes directly from the activity module. Four operating modes are included in the DrayFLEET Model: idle, creep, transient, and cruise. The activity portions of the model yield estimates of minutes spent by drayage tractors in each of these modes. As of September 2010, the emissions portion of the model uses a mode conver- sion factor to bridge the gap between the detailed drayage activity model output and the emis- sions factors in MOBILE 6.2. Subsequent versions of the model will be updated to use the current EPA emissions methodologies. Port-Area Emissions Estimates The percentage impact of these or any emissions or activity changes depends on the context. Emissions inventories typically define a target area in the near vicinity of the port, consistent with the limited ability of the port or the terminal operators to affect drayage activities outside the port area. DrayFLEET, on the other hand, captures the full range and impact of port-related drayage activity at any distance. To do so, DrayFLEET uses weighted average distances to off-dock rail terminals, container depots, and--most critically--shippers and receivers. Rail ter- minals and container depots are typically within a few miles of the port, but shippers and receivers can be spread out over a broad region. A major limitation on the percentage impact of marine terminal efficiency or emissions mea- sures is the share of all drayage activity associated with the marine terminals. Figure 123, extracted from the generic model activity summary, highlights the trips, miles, and hours in the various major activity categories. The marine terminal accounts for about 76% of the trips, but only 25% of the miles and 49% of the hours. Shipper/receiver movements account for 41% of the trips, but 67% of the miles and 41% of the hours. The miles and hours generated by drayage trips to and from distant customers can outweigh and obscure the impacts of port-area changes. Figure 124 provides an example of this relation- ship. In this figure, the 25-mile default value for the weighted average trip to shippers and receivers was changed to 5 miles. That change reduced drayage VMT by 52.9%, drayage hours by 26.7%, emissions and fuel use by 41.9% to 45.4%, and cost by 29.3%. In other words, the additional 20 miles (one way) to shippers and receivers accounted for over half the drayage miles, 26.7% of the hours, 41.9% to 45.4% of the emissions and fuel, and 29.3% of the cost. Table 121 compares the drayage hours by category for a 25-mile scope and a 5-mile scope. In addition to the overall reduction in total and average hours, the proportions of idle, creep, Activity Group Number of Trips Distance (Miles) Total (hours) Marine Terminal 2,917,414 17,012,538 2,533,308 Inter-Terminal 5,714 22,857 878 Off-Dock Rail Terminal 346,909 1,367,673 164,735 Container Depot 69,917 154,697 27,401 Shippers & Receivers 1,811,250 45,589,163 2,136,895 Crosstown Trips 426,588 4,267,065 340,110 Other Port Trucks - - - Net Total* 3,826,235 68,413,994 5,203,327 *Subtotals and total are corrected to remove double-counting of marine terminal trips. Figure 123. Marine terminal vs. shipper/receiver activity.

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92 Truck Drayage Productivity Guide SmartWay DrayFLEET Version 1.0 Primary Inputs & Outputs DrayFLEET Version 1.0E of 06/26/2008 Primary Inputs Default Scenario Port Generic Port Terminal(s) All Calendar Year 2007 2007 Scenario Five-mile versus 25-mile Limits Annual TEU 2,000,000 2,000,000 Average TEU per Container 1.75 1.75 Inbound Share 50% 50% Inbound Empty Share 5% 5% Date 6/26/2008 Outbound Empty Share 25% 25% Rail Intermodal Share 25% 25% Activity Outputs Default Scenario Change % Change Marine Terminals Annual Activity Average Inbound Gate Queue Minutes 15 15 Number of Drayage Trip Legs 3,826,235 3,826,235 0 0.0% Average Marine Terminal Min. per Transaction 30 30 Drayage Trip Legs per Container 3.3 3.3 0.0 0.0% Rail Terminals Total Drayage VMT 68,413,994 32,188,994 -36,225,000 -52.9% Weighted Average Miles from Port 5 5 Drayage VMT per Container 59.9 28.2 -31.7 -52.9% Average Inbound Gate Queue Minutes 5 5 Fleet Required (FTE Tractors) 1,756 1,286 -469 -26.7% Average Rail Yard Min. per Transaction 15 15 Annual Duty Cycle Totals Container Depots Idle Hours 1,957,060 1,725,478 -231,582 -11.8% Weighted Average Miles from Port 2 2 Creep Hours 1,089,182 991,532 -97,651 -9.0% Share of Empties Stored at Depots 10% 10% Transient Hours 597,318 339,489 -257,828 -43.2% Container Shippers/Receivers Cruise Hours 1,559,766 755,790 -803,977 -51.5% Weighted Average Miles from Port 25 5 Total Drayage Hours 5,203,327 3,812,289 -1,391,038 -26.7% Weighted Average Crosstown Trip Miles 10 10 Drayage Hours per Container 4.6 3.3 -1.2 -26.7% Cost Factors Average Drayage Labor Cost per Hour $ 12.00 $ 12.00 Emissions Outputs Default Scenario Change % Change Average Diesel Fuel Price per Gallon $ 4.00 $ 4.00 Pollutant (annual tons) HC 55 32 -23.34 -42.3% Initiative Inputs Default Scenario CO 311 181 -130.12 -41.9% Port/Terminal Initiatives NOx 1,154 637 -517.58 -44.8% Stacked Terminal (% stacked) 0% 0% PM10 38 21 -17.27 -45.4% On-Dock Rail (% of rail on-dock) 0% 0% PM2.5 32 18 -14.60 -45.4% Automated Gates (% of gate transactions) 0% 0% CO2 145,037 79,582 -65,455 -45.1% Extended Gate Hours (% off-peak, 50% max) 0% 0% Fuel Use and Total Cost Container Info System (% used) 0% 0% Fuel - Gallons 12,963,067 7,112,838 -5,850,228.3 -45.1% Virtual Container Yard (% available) 0% 0% Total Drayage Cost $ 185,045,398 $ 130,800,961 $ (54,244,438) -29.3% Neutral Chassis Pool (% used) 0% 0% Drayage Cost per Container $ 162 $ 114 $ (47) -29.3% Figure 124. Five-Mile scenario versus 25-mile default. transient, and cruise hours shift noticeably. With a 25-mile scope, 30% of the hours are spent in cruise mode. Activity within 5 miles of the port, however, is dominated by idling at 45% of the total hours. Initiatives and Technology Impacts Modeling the emissions impacts of port and terminal management initiatives (such as neu- tral chassis pools and automated gates) was a major reason for developing DrayFLEET. Likewise, DrayFLEET is intended to estimate the impacts of truck and engine technology such as diesel particulate filters or idling controls. The EPA SmartWay Program offers freight carriers technical and financial information on a range of truck and engine technologies and practices designed to conserve fuel and reduce emis- sions. Many of the applicable options have been built into DrayFLEET, as shown in Figure 125. Table 121. Scope comparison. Category Default - 25-Mile Trips Port Vicinity - 5-Mile Trips Idle Hours 1,957,060 38% 1,725,478 45% Creep Hours 1,089,182 21% 991,532 26% Transient Hours 597,318 11% 339,489 9% Cruise Hours 1,559,766 30% 755,790 20% Total Drayage Hours 5,203,327 100% 3,812,289 100% Drayage Hours per Container 4.6 3.3