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Emissions and Cost Impacts 95 Table 122. DrayFLEET modeling results. Hours Fuel CO2 NOx PM 2.5 Cost Scenario (million) (million gal.) (tons) (tons) (tons) (million) 2008 National Default 39.1 69.9 782,613 7,678 149 $1,440.00 30 vs. 40 Minute Terminal Time (3.2) (1.4) (15,652) (160) (3) $(79) Change -8.1% -2.0% -2.0% -2.1% -1.9% -5.5% 10 vs. 20 Minute Queue Time (2.7) (2.0) (21,913) (225) (4) $(69) Change -6.8% -2.8% -2.8% -2.9% -2.7% -4.8% 3% vs. 5% Trouble Tickets (0.3) (0.1) (1,632) (17) (0) $(8) Change -0.8% -0.2% -0.2% -0.2% -0.2% -0.5% 0% vs. 5% Trouble Tickets (0.8) (0.3) (3,913) (42) (1) $(20) Change -2.0% -0.5% -0.5% -0.5% -0.5% -1.4% Idling Control - 50% - (5.9) (65,739) (450) (8) $(17) Change 0.0% -8.4% -8.4% -5.9% -5.4% -1.2% 100% vs. 20% Neutral Pools (0.8) (0.3) (3,913) (42) (1) $(20) Change -2.0% -0.5% -0.5% -0.6% -0.5% -1.4% Trucker-Supplied Chassis (6.1) (4.4) (49,305) (503) (9) $(137) Change -15.6% -6.3% -6.3% -6.6% -6.1% -9.5% Combined Strategies (14.5) (9.9) (111,050) (979) (18) $(202) Change -37.1% -14.2% -14.2% -12.8% -11.8% -14.0% As Table 122 shows, those tractors emitted an estimated 7,678 tons of NOx and 149 tons of PM2.5, as well as other criteria pollutants. The estimated total port-area drayage cost was $1.44 billion, an average of about $112 per con- tainer. That total included about $210 million in fuel costs at $3 per gallon, which accounted for 4.6% of the total cost. Impacts of Drayage Bottlenecks DrayFLEET can be used to estimate the impacts of bottlenecks and sources of delay identified in the study. As an illustration, Table 122 also summarizes the results of national scenario esti- mates made in the course of NCFRP Project 14. Terminal and Queue Time Reduction The default national model was configured with a 60-minute average port turn time divided into 20 minutes of queuing outside the gate and 40 minutes inside the terminal. Reduction of the average terminal time from 40 minutes to 30 minutes would reduce the total time required by about 3 million hours (8.1%), and the fuel burned by about 1 million gallons (2.1%). CO2 emissions would also drop by 2.0%. NOx would drop by 160 tons (2.09%) and PM 2.5 by 3 tons (1.9%). The annual cost savings would be about $79 million. If the average queue time were reduced from 20 minutes to 10 minutes, the impacts would be similar (Table 122), although the fuel and emissions savings would be greater due to the greater reduction in the relatively inefficient and "dirty" stop-and-go queuing operations. If both the terminal time and the queue time were reduced by 10 minutes the impacts would be additive. Trouble Ticket Reduction In NCFRP Project 14, the study team found that experienced draymen appear to average about 3% trouble tickets (exceptions), although the overall average was 5%. Reducing the incidence of

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96 Truck Drayage Productivity Guide trouble tickets from 5% to 3% would save about 300,000 hours of drayage time, 100,000 gallons of fuel, 17 tons of NOx, and $8 million dollars in port-area drayage costs. If trouble tickets could be completely eliminated (0%), the savings would be greater yet: 800,000 drayage hours, 300,000 gallons of fuel, 42 tons of NOx, 1 ton of PM 2.5, and $20 million. These potential savings are therefore the estimated costs of trouble tickets. Idling The estimated 46% of drayage time spent idling, which accounts for nearly 18 million hours nationwide, suggests large potential benefits from idling controls or hybrid truck tractors that would neither burn fuel nor emit pollutants when they were not moving. If the tractor engines could be turned off for half of the time they are now estimated to be idling, yearly fuel use would drop by 5.9 million gallons. Greenhouse gasses (CO2) would be reduced by over 65,000 tons, NOx would decline by 450 annual tons, and PM 2.5 would decline by 8 tons in port areas. The fuel saving would reduce drayage cost by about $17 million annually. The hours required would not decline, but for half the 18 million idling hours, the engines would be off. Chassis Logistics The EPA SmartWay Program has identified chassis pooling as a promising strategy for improv- ing drayage efficiency and reducing emissions. The DrayFLEET modeling bears out this conclu- sion. With an assumed 50% of the containers being stacked in the terminals, raising the default 20% usage of neutral chassis pools to 100% usage yielded almost exactly the same benefits as elim- inating trouble tickets (Table 122). The benefits of neutral chassis pools show up in the model mostly as reduced chassis search time. A shift to trucker-supplied chassis yielded the greatest benefits of the individual scenarios shown in Table 122. Modeling a trucker-supplied chassis system entailed the following: Raising the share of containers stacked from 50% to 100%, Eliminating chassis search time and bare chassis drop-off time, Reducing overall in-terminal time by 10 minutes per move, Reducing average gate transaction times from 5 minutes to 3 minutes, Reducing average queue times from 20 minutes to 15 minutes, and Adding $2 per move (about $6 per day) to drayage costs to account for truckers' chassis supply costs. Although these modeling changes are necessarily inexact approximations of an emerging system, they indicate the kinds of pervasive changes that can be expected. The estimated benefits of trucker-supplied chassis include an annual savings of over 6 mil- lion hours of driver and tractor time, over 4 million gallons of fuel, and $137 million in drayage costs. CO2 emissions would decline by an estimated 49,305 tons. Port-area NOx would decline by an estimated 503 tons, and PM 2.5 by 9 tons. Combined Impacts and Benefits Combining all of the scenarios yields an estimate of the improvements possible if queuing were to be minimized, trouble tickets eliminated, idling control implemented on half the fleet, and the transition to trucker-supplied chassis completed. As Table 122 indicates, the benefits would be substantial and indicate the value of progress toward drayage bottleneck solutions as follows: A 37.1% reduction in total hours--14.5 million hours of driver and tractor time annually, A 14.2% reduction in fuel use--an annual savings of nearly 10 million gallons of diesel fuel,