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5 - 1 

# Chapter 5: **Impacts on Emissions**  **and Fuel Consumption 5.1**  **Executive Summary** Climate change is widel y viewed as the most significant long - term threat to the global environment. According to the IPCC, it is extremely likel y (> 95 percent probability) that human influence was the dominant cause of the observed warming since the mid- 20th century . The primary GHGs of concern are carbon dioxide (CO 2 

### ), methane (CH4 

### ) , nitrous oxide (N2 

### O) , hydrofluoro carbons (HFCs) , perfluorocarbons, and sulfur hexafluoride. 1 

### Mobile sources emitted 28 percent of all U.S. GHG s in 20 12 when considering all upstream and downstream emissions , and the transportation - related GHG s alone have grown 18 percent between 1990 and 2012 . 2 

### Mobile sources addressed in the recent endangerment finding under CAA S ection 202(a)

– highway vehicles including passenger cars, light- duty trucks , heavy- duty trucks, buses, and motorcycles

– accounted for 2 4 percent of all U.S. GHG s in 20 12 . 3 

### H eavy- duty vehicles emit CO 2 

### , methane, nitrous oxide, and hydrofluorocarbons and are responsible for almost 22 percent of all mobile source GHGs ( over 6 percent of all U.S. GHGs) and about 2 6 p ercent of CAA S ection 202(a) mobile source GHGs . For heavy- duty vehicles in 2007 , CO 2 

### emissions represented nearl y 97 percent of all GHG emissions (including HFCs ) . 4 

### This chapter provides the anticipated emissions impacts from the proposed standards. In addition, the emissions impacts of Alternative 4 are presented because the agencies are carefull y considering it along with the preferred alternative . The reductions in emissions are expected for carbon dioxide (CO 2 

### ), methane (CH4 

### ), nitrous oxide (N2 

### O) and hydrofluorocarbons (HFCs ) . In addition to reducing the emiss ions of greenhouse gases, this program would also affect the emissions of “criteria” air pollutants and their precursors , including carbon monoxide (CO), fine particulate matter (PM 2.5 

### ) , oxides of sulfur (SO X

### ) , volatile organic compounds (VOC) and oxides of nitrogen (NO X

### ) , and several air toxics , such as benzene, 1,3 -butadiene, formaldehyde, acetaldehyde, and acrolein. The proposed standards will affect both diesel - and gasoline - fueled heavy- duty vehicles , as well as those running on natural gases. The an alyses account for both vehicle emission s (“downstream” emissions) and emissions from fuel production and distribution (“upstream” emissions). The agencies conducted coordinated and complementary analyses by

employing both DOT’s CAFE model and EPA’s Motor Vehicle Emission Simulator (MOVES2014) 5 

### , relative to different reference cases (i.e., different baselines). The agencies used EPA’s MOVES model to estimate fuel consumption and emissions impacts for tractor- trailers (including the engines which power the vehicle), and vocational vehicles (including the engine which powers the vehicle). For heavy- duty pickups and vans, the agencies performed complementary anal ys es , using the CAFE model (“Method A”) and the MOVES model (“Method B”) , to estimate fuel consumption and emissions from these vehicles. See Section 5.3 for additional details. The changes in u

pstream emission s result from decreased fuel consumption . The emission factors from GREET 6 

### were used to estimate the changes in upstream emissions. In some cases, the GREET values were modified or updated b y the agencies to be consistent with the EPA’s National Emission Inventory (NEI) and emission factors from MOVES .

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5 - 2 Table 5 - 1 through Table 5 - 3 summarize the impact of the proposed program on GHG emissions from the heavy- duty sector in calendar years 2025, 2035 and 2050 , using Method A and B, relative to two reference cases

– more dy namic and less dy

namic . Table 5 - 4 through Table 5 - 6 summarize the projected fuel savings from the proposed program in calendar ye ars 2025, 2035 and 2050, using Method A and B , relative to the two reference cases. The comparable anal ys es for Alternative 4 are summarized in Table 5 - 7 through Table 5 - 12 . **Table 5**  **- 1**  **Annual Total Reductions of Heavy -** **Duty GHG Emissions in Calendar Years 2025, 2035 and 2050**  **– Preferred Alternative vs. Alt 1b**  **using Analysis Method A a**  CY 2025 (MMT CO 2 EQ) 2035 (MMT CO 2 EQ) 2050 (MMT CO 2 EQ) Downstream 27.2 86.9 123 .0 Upstream 9.3 29.7 42 .0 HFC 0.09 0.25 0.3 Total 36. 6 116. 9 165.3 Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1 **Table 5**  **- 2**  **Annual Total Reductions of Heavy -** **Duty GHG Emissions in Calendar Years 2025, 2035 and 2050 –**  **Preferred Alternative vs. Alt 1a using Analysis Method A a**  CY 2025 (MMT CO 2 EQ) 2035 (MMT CO 2 EQ) 2050 (MMT CO 2 EQ) Downstream 28.1 94.6 134.9 Upstream 9.6 32.3 46.1 HFC 0.09 0.25 0.3 Total 37. 8 127. 2 181.3 Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1 **Table 5**  **- 3**  **Annual Total Reductions of Heavy -** **Duty GHG Emissions in Cale ndar Years 2025, 2035 and 2050**  **– Preferred Alternative vs. Alt 1a using Analysis Method B**  **a** CY 2025 (MMT CO 2 EQ) 2035 (MMT CO 2 EQ) 2050 (MMT CO 2 EQ) Downstream 27.4 94.7 136.5 Upstream 9. 3 32.2 46. 5 HFC 0.1 0.25 0.3 Total 36. 8 127.2 183. 3 Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1

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5 - 3 **Table 5**  **- 4**  **Annual Fuel Savings in Calendar Years 2025, 2035 and 2050 –**  **Preferred Alternative vs. Alt 1b using Analysis Method A**  **a** CY2025 CY2035 CY2050 Billion Gallons % Reduction Billion Gallons % Reduction Billion Gallons % Reduction Diesel 2.5 5.1 % 7.6 14.3 % 10.8 17 .0 % Gasoline 0.2 2.4 % 0.9 11 .0 % 1.2 13.2 % Total 2.7 4.7 % 8.5 13.8 % 12 .0 16.5 % Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1 **Table 5**  **- 5**  **Annual Fuel Savings in Calendar Years 2025, 2035 and 2050 –**  **Preferred Alternative vs. Alt 1a using Analysis Method A**  **a** CY2025 CY2035 CY2050 Billion Gallons % Reduction Billion Gallons % Reduction Billion Gallons % Reduction Diesel 2.5 5.2 % 8.3 15.4 % 11.9 18.4 % Gasoline 0.2 2.6 % 1 .0 11.5 % 1.3 13.7 % Total 2.7 4.8 % 9.3 14.8 % 13.2 17.8 % Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1 **Table 5**  **- 6**  **Annual Fuel Savings in Calendar Years 2025, 2035 and 2050 –**  **Preferred Alternative vs. Alt 1a using Analysis Method B**  **a** CY2025 CY2035 CY2050 Billion Gallons % Reduction Billion Gallons % Reduction Billion Gallons % Reduction Diesel 2.5 5.1% 8.5 15.6% 12.3 18.7% Gasoline 0.2 2.1% 0.8 10.4% 1.1 12.8% Total 2.7 4.7% 9.3 14.9% 13.4 18.0% Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1 **Table 5**  **- 7**  **Annual Total Reductions of Heavy -** **Duty GHG Emissions in Calendar Years 2025, 2035 and 2050 –**  **Alternative 4 vs. Alt 1b using Analysis Method A a**  CY 2025 (MMT CO 2 EQ) 2035 (MMT CO 2 EQ) 2050 (MMT CO 2 EQ) Downstream 33.5 90.9 124 .0 Upstream 11.5 31 .0 42.3 HFC 0.09 0.25 0.3 Total 45. 1 122. 2 166.6 Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1

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5 - 4 **Table 5**  **- 8**  **Annual Total Reductions of Heavy -** **Duty GHG Emissions in Calendar Years 2025, 2035 and 2050 –**  **Alternative 4 vs. Alt 1a using Analysis Method A a**  CY 2025 (MMT CO 2 EQ) 2035 (MMT CO 2 EQ) 2050 (MMT CO 2 EQ) Downstream 34.6 98.7 136 .0 Upstream 11.8 33.7 46.5 HFC 0.09 0.25 0.3 Total 46. 5 132. 7 182.8 Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1 **Table 5**  **- 9**  **Annual Total Reductions of Heavy -** **Duty GHG Emissions in Calendar Years 2025, 2035 and 2050 –**  **Alternative 4 vs. Alt 1a using Analysis Method B a**  CY 2025 (MMT CO 2 EQ) 2035 (MMT CO 2 EQ) 2050 (MMT CO 2 EQ) Downstream 33.7 98. 3 136. 9 Upstream 11.5 33. 4 46.6 HFC 0.1 0.25 0.3 Total 45.3 132.0 183. 8 Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1 **Table 5**  **- 10**  **Annual Fuel Savings in Calendar Years 2025, 2035 and 2050 –**  **Alternative 4 vs. Alt 1b using Analysis Method A**  **a** CY2025 CY2035 CY2050 Billion Gallons % Reduction Billion Gallons % Reduction Billion Gallons % Reduction Diesel 3 .0 6.1 % 7.9 14.8 % 10.8 17 .0 % Gasoline 0.3 3.9 % 1 .0 12.1 % 1.3 13.8 % Total 3.3 5.8 % 8.9 14.4 % 12.1 16.6 % Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1 **Table 5**  **- 11**  **Annual Fuel Savings in Calendar Years 2025, 2035 and 2050 –**  **Alternative 4 vs. Alt 1a using Analysis Method A**  **a** CY2025 CY2035 CY2050 Billion Gallons % Reduction Billion Gallons % Reduction Billion Gallons % Reduction Diesel 3.1 6.3 % 8.6 16 .0 % 12 .0 18.5 % Gasoline 0.3 4.3 % 1.1 12.5 % 1.3 14.3 % Total 3.4 6 .0 % 9.7 15.5 % 13.3 18 .0 % Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1

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5 - 5 **Table 5**  **- 12**  **Annual Fuel Savings in Calendar Years 2025, 2035 and 2050 –**  **Alternative 4 vs. Alt 1a using Analysis Method B**  **a** CY2025 CY2035 CY2050 Billion Gallons % Reduction Billion Gallons % Reduction Billion Gallons % Reduction Diesel 3.1 6.2% 8.8 16.1% 12. 3 18.7% Gasoline 0. 3 3.4% 0.9 11.1% 1.1 12.9% Total 3. 4 5.9% 9.7 15.5% 13. 4 18.0% Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1 

### The non - GHG impacts of the proposed rulemaking are largel y driven by three factors. The largest contributor is from the projected increased use of auxiliary power units (APUs) , which provide power, heat and cooling for trucks during extended engine idling . Reduced emissions from upstream fuel production and distribution also contribute significantly to the emissions benefits . Emissions of certain pollutants , such as NO X 

### and PM 2.5 

### are further reduced through improved engine efficiency, aerodynamics and tire rolling resistance and absolute changes in average total running weight o f the vehicles . To a smaller extent, a rebound of vehicle miles trave led (VMT ) would increase the emissions of all pollutants proportional to the VMT rebound amount. The emissions impacts of non - GHG s on both downstream and upstream from the heavy- duty

sector in calendar ye ars 2025, 2035 and 2050 are summarized in Table 5 - 13 through Table 5 - 15 , using Method A and B , relative to the two reference cases . The comparable anal ys es for Alternative 4 are summarized in Table 5 - 16 through Table 5 - 18 . **Table 5**  **- 13**  **Annual Total Reductions (Upstream and Downstream** **) of Heavy -** **Duty Non -**  **GHG Emissions –**  **Preferred Alternative vs. Alt 1b using Analysis Method A a**  POLLUTANT CY2025 CY2035 CY2050

US Short Tons % Reduction US Short Tons % Reduction US Short Tons % Reduction 1,3 -Butadiene 9 3 % 25 13 % 34 16 % Acetaldehyde 672 10 % 1,893 30 % 2,682 36 % Acrolein 97 10 % 273 31 % 387 37 % Benzene 145 5 % 421 18 % 595 22 % CO 30,282 3 % 87,286 8 % 123,876 10 % Formaldehyde 2,119 11 % 5,969 32 % 8,460 37 % NO X 101,916 7 % 291,282 26 % 413,501 31 % PM 2.5 376 1 % 1,535 3 % 2,199 4 % SO X 6,213 5 % 1 9,905 14 % 28,101 17 % VOC 16,227 6 % 49,080 18 % 69,525 22 % Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1

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5 - 6 **Table 5**  **- 14**  **Annual Total Reductions (Upstream and Downstream** **) of Heavy -** **Duty Non -**  **GHG Emissions –**  **Preferred Alternative vs. Alt 1a using Analysis Method A a**  POLLUTANT CY2025 CY2035 CY2050

US Short Tons % Reduction US Short Tons % Reduction US Short Tons % Reduction 1,3 -Butadiene 9 3% 25 13% 35 16% Acetaldehyde 672 10% 1,891 30% 2,680 36% Acrolein 97 10% 273 31% 386 37% Benzene 145 5% 425 18% 603 22% CO 30,487 3% 88,724 8% 126,081 10% Formaldehyde 2,119 11% 5,969 32% 8,461 37% NO X 102,983 7% 299,911 26% 427,332 32% PM 2.5 419 1% 1,910 4% 2,791 5% SO X 6,421 5% 21,672 15% 30,850 18% VOC 16,403 6% 50,812 19% 72,253 23% Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1 **Table 5**  **- 15**  **Annual Total Reductions (Upstream and Downstream** **) of Heavy -** **Duty Non -**  **GHG Emissions –**  **Preferred Alternative vs. Alt 1a using Analysis Method B a**  POLLUTANT CY2025 CY2035 CY2050

US Short Tons % Reduction US Short Tons % Reduction US Short Tons % Reduction 1,3 -Butadiene 9 2.7% 25 15.1% 36 19.4% Acetaldehyde 674 10.1% 1,902 30.5% 2,697 36.0% Acrolein 97 9.8% 274 31.3% 388 36.9% Benzene 149 5.4% 445 18.8% 633 22.9% CO 29,622 1.9% 85,961 6.6% 122,659 8.4% Formaldehyde 2,121 11.4% 5,978 31.7% 8,475 37.0% NO X 102,502 7.2% 298,907 26.6% 426,610 32.1% SO X 386 0.6% 1,883 4.2% 2,815 5.4% PM 2.5 6,070 4.9% 20,777 15.3% 30,000 18.4% VOC 16,724 5.6% 52,872 18.8% 75,521 22.7% Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1

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5 - 7 **Table 5**  **- 16**  **Annual Total Reductions (Upstream and Downstream** **) of Heavy -** **Duty Non -**  **GHG Emissions –**  **Alternative 4 vs. Alt 1b using Analysis Method A a**  POLLUTANT CY2025 CY2035 CY2050

US Short Tons % Reduction US Short Tons % Reduction US Short Tons % Reduction 1,3 -Butadiene 9 3 % 25 13 % 34 16 % Acetaldehyde 673 10 % 1,893 30 % 2,682 36 % Acrolein 97 10 % 273 31 % 387 37 % Benzene 152 6 % 426 18 % 595 22 % CO 31,383 3 % 88,047 8 % 124,137 10 % Formaldehyde 2,123 11 % 5,970 32 % 8,460 37 % NO X 105,693 7 % 293,918 26 % 413,967 31 % PM 2.5 639 1 % 1,703 4 % 2,237 4 % SO X 7,682 6 % 20,849 15 % 28,385 17 % VOC 18,006 6 % 50,189 19 % 69,796 22 % Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1 **Table 5**  **- 17**  **Annual Total Reductions (Upstream and Downstream** **) of Heavy -** **Duty Non -**  **GHG Emissions –**  **Alternative 4 vs. Alt 1a using Analysis Method A a**  POLLUTANT CY2025 CY2035 CY2050

US Short Tons % Reduction US Short Tons % Reduction US Short Tons % Reduction 1,3 -Butadiene 9 3 % 25 13 % 35 16 % Acetaldehyde 672 10 % 1,891 30 % 2,679 36 % Acrolein 97 10 % 273 31 % 386 37 % Benzene 153 6 % 430 18 % 603 22 % CO 31,637 3 % 89,514 8 % 126,360 10 % Formaldehyde 2,123 11 % 5,969 32 % 8,460 37 % NO X 106,822 7 % 302,575 26 % 427,805 32 % PM 2.5 689 1 % 2,082 5 % 2,833 5 % SO X 7,941 6 % 22,646 16 % 31,151 18 % VOC 18,222 6 % 51,924 19 % 72,509 23 % Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1

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5 - 8 **Table 5**  **- 18**  **Annual Total Reductions (Upstream and Downstream** **) of Heavy -** **Duty Non -**  **GHG Emissions –**  **Alternative 4 vs. Alt 1a using Analysis Method B a**  POLLUTANT CY2025 CY2035 CY2050

US Short Tons % Reduction US Short Tons % Reduction US Short Tons % Reduction 1,3 -Butadiene 9 2.8% 26 15.2% 36 19.4% Acetaldehyde 676 10.1% 1,903 30.6% 2,697 36.0% Acrolein 97 9.8% 274 31.3% 388 36.9% Benzene 157 5.7% 450 18.9% 634 22.9% CO 30,580 1.9% 86,526 6.6% 122,703 8.4% Formaldehyde 2,125 11.4% 5,980 31.7% 8,476 37.0% NO X 106,180 7.4% 301,339 26.8% 426,796 32.1% SO X 646 1.1% 2,036 4.6% 2,827 5.4% PM 2.5 7,450 6.1% 21,550 15.9% 30,364 18.4% VOC 18,652 6.2% 53,966 19.2% 75,621 22.7% Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1 

## 5.2 **Introduction 5.2.1**  **Dow nstream**  **(Tailpipe) Emissions**  As described in more detail in this chapter , the downstream reductions in emissions due to the proposed program are anticipated to be achieved through improvements in engine efficiency, road load reduction, and APU use during extended idling, with the exception of PM 2.5 

### . A 

### Absolute reductions in tailpipe emissions are projected to grow over time as the fleet turns over to vehicles affected b y the proposed standards, meaning that the emissions benefit s of the program would continue to grow as older vehicles in the fleet are replaced b y newer vehicles that emit less CO 2 

### . The effect of the regulations on the timing of fleet turnover and total VMT can have an impact on downstream GHG and other emissions , as discussed in S ection IX of the preamble. If the regulations spur firms to increase their purchase of new vehicles before efficiency standards are in place (“pre -buy”) or to delay their purchases once the standards are in place then there would be a delay

in achieving the full GHG and other emission reductions from improved fuel economy across the fleet. If the lower per- mile costs associated with higher fuel economy lead to an increase in VMT (the “rebound effect”), then the total emission reductions would also be reduced. Chapter 8 of the draft RIA provides more detail on how the rebound effect was calculated in the agencies’ anal ys is. The analysis discussed in this chapter incorporates the rebound effect into the estimates . However, the impacts of any delayed fleet turnover are not estimated. A The projected increased use of APUs wo uld lead to higher PM 2.5 emissions since engines powering APUs are currently required to meet less stringent PM standards than on-road engines .

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5 - 9 

### 5.2.2 **Upstream Emissions**  In addition to downstream emission reductions, reductions are expected in the emissions associated with the processes involved in getting fuel to the pump, including the extraction and transportation of crude oil, the production and distribution of finished gasoline and diesel , and the production and transportation of renewable fuels . Changes are anticipated in upstream emissions due to the expected reduction in the overall volume of gasoline and diesel consumed. Less fuel consumed means less f uel transported, less fuel refined, and less crude oil extracted and transported to refineries. Thus, there would be reductions in the emissions associated with each of these steps in the fuel production and distribution process es . In addition, any chang es in downstream reductions associated with changes in fleet turnover, and VMT are reflected in a corresponding change in upstream emissions associated with fuel processing and distribution. The agencies recognize that the proposed standards could lower the world price of oil (the “monopsony” effect, further discussed in Chapter 8 of the draft RIA). Lowering oil prices could lead to an uptick in oil consumption globally, resulting in a corresponding increase in GHG emissions in other countries. This global increase in emissions could slightly offset some of the emission reductions achieved domestically as a result of the regulation. EPA does not provide quantitative estimates of the impact of the proposed regulation on global petroleum consumption and GHG emissions in this draft RIA. 

### 5.2.3 **Global Warming Potentials** Throughout this document, in order to refer to the four inventoried greenhouse gases on an equivalent basis, Global Warming Potentials (GWPs) are used. In simple terms, GWPs provide a common basis with which to combine several gases with different heat trapping abilities into a single inventory ( Table 5 - 19 ). When expressed in CO 2 

### eq terms, each gas is weighted b y its heat trapping ability relative to that of CO 2 

### . The GWPs used in this analysis are consistent with the 2007 Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report (AR4) on a 100 - year timescale . 7 **Table 5**  **- 19**  **Global Warm ing Potentials**  **of GHGs**  GAS GLOBAL WARMING POTENT IAL (CO 2 EQ ) CO 2 1 CH4 25 N2 O 298 HFC 134a 1,430 

## 5.3 **Program Analysis and Modeling Methods 5.3.1**  **Models Used** Different tools exist for estimating potential fuel consumption and emissions impacts associated with fuel efficiency and GHG emissions standards. One such tool is EPA’s official mobile source emissions inventory model named Motor Vehicle Emissions Simulator (MOVES) . 8 

### The agencies used the most current version of the model, MOVES2014, to quantify

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5 - 10 the impacts of these proposed standards on GHG emissions , fuel consumption , as well as criteria pollutants and air toxics emissions . InMOVES, vehicle types are categorized by their use and represented b y combination tractors, single unit trucks, refuse trucks, motor homes, transit buses, intercity buses, school buses, and light commercial trucks. The agencies ran MOVES with user input databases that reflected the projected technological improvements resulting from the proposed rules, such as the improvements in engine and vehicle efficiency, aerodynamic drag, and tire rolling resistance. The changes made to the default MOVES database are described below in Section 5.3.2 . All the input data , MOVES run spec files , and the scripts used for the anal ys i s , as well as the version of MOVES used to generate the emissions inventories , can be found in the docket. 9 

### Another such tool is DOT’s CAFE model. For this analysis, the model was reconfigured to use the work based attribute metric of “work factor” establ ished in the Phase 1 rule for heavyduty pickups and vans , instead of the light- duty “footprint” attribute metric. The CAFE model takes user- specified inputs on, among other things, vehicles that will be produced in a given model year, technologies availa ble to improve fuel efficiency on those vehicles, potential regulatory

standards that would drive improvements in fuel efficiency, and economic assumptions. The CAFE model takes every vehicle in each manufacturer’s fleet and decides what technologies to add to those vehicles in order to allow each manufacturer to comply with the standards in the most cost- effective way and uses a representation of the HD pickup and van fleet that captures heterogeneity at the manufacturer, model year, and powertrain (and o ther technology) level. Based on the resulting improved vehicle fleet, the CAFE model then calculates total fuel consumption and GHG, criteria, and toxics emissions impacts based on those inputs, along with economic costs and benefits. The CAFE model is discussed in greater detail in Chapter 10 of the draft RIA. For this rule, the agencies conducted coordinated and complementary analyses by employing both DOT’s CAFE model and EPA’s MOVES model. These models were used to project the impacts resulting from the proposed standards on fuel consumption, GHG emissions, as well as criteria pollutants and air toxics emissions. As described in Section 5.3.2 , the agencies used EPA’s MOVES model to estimate fuel consumption and emissions impacts for tractor- trailers (including the engines which power the vehicle), and vocational vehicles (including the engine which powers the vehicle). For heavy- duty pickups and vans, the agencies performed complementary analyses using the CAFE model (“Method A”) and the MOVES model (“Method B”) to estimate fuel consumption and emissions from these vehicles. For both methods, the agencies analyzed the impact of the proposed rules, relative to two different reference cases

– less dynamic and more dyn amic. The less dy namic baseline projects very little improvement in new vehicles in the absence of new Phase 2 standards. In contrast, the more dy namic baseline projects more improvements in vehicle fuel efficiency . The agencies considered both reference cases , reaching corroborative conclusions . The results for all of the regulatory

alternatives relative to both reference cases, derived via the same methodologies discussed in this Chapter , are presented in Chapter 11 of the draft RIA and these different anal ys es all support the reasonableness of the proposed standards . For brevity, a subset of these anal ys es are presented in this section , and the reader is referred to both the Chapter 11 of the draft RIA and NHTSA’s DEIS Chapters 3 and 5 for complete sets of these analyses . In this Chapter, Method A is presented for both the proposed

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5 - 11 standards (i.e., Alternative 3

– the agencies’ preferred alternative) and for the standards the agencies c onsidered in Alternative 4. Method A is presented relative to both the more dy namic baseline (Alternative 1b) and the less dynamic baseline (Alternative 1a). Method B is presented also for the proposed standards and Alternative 4, but relative only to the less dy namic baseline. The agencies’ intention for presenting both of these complementary and coordinated anal ys es is to offer interested readers the opportunity to compare the regulatory alternatives considered for Phase 2 in both the context of our HD Phase 1 analy tical approaches and our light- duty vehicle anal ytical approaches. The agencies view these analyses as corroborative and reinforcing: both support agencies’ conclusion that the proposed standards are appropriate and at the maximum feasible l evels. Because reducing fuel consumption also affects emissions that occur as a result of fuel production and distribution (including renewable fuels), the agencies also calculated those “upstream” changes using the “downstream” fuel consumption reductions predicted b y the MOVES model for vocational vehicles and tractor- trailers. As described earlier , f or HD pickups and vans, parallel and complementary anal ys es of estimating the emissions from upstream processes were conducted using the fuel consumption es timates from both DOT’s CAFE model (Method A) and EPA’s MOVES model (Method B), relative to the two reference cases. Method A use d the CAFE model to estimate vehicular fuel consumption and emissions impacts for HD pickups and vans and to calculate upstream impacts . For vocational vehicles and combination tractor- trailers, both Method A and Method B estimated the projected corresponding changes in upstream emissions using the same tools originally created for the Renewable Fuel Standard 2 (RFS2) rulemaking anal ysis, 10 

### used in the LD GHG rulemakings, 11 

### HD GHG Phase 1, 12 

### and updated for the current analysis. The estimate of emissions associated with production and distribution of gasoline and diesel from crude oil is based on emission factors in the “Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation” model ( GREET ) developed b y DOE's Argonne National Lab. In some cases, the GREET values were modified or updated by the agencies to be consistent with the National Emission Inventory (NEI) and emission factors from MOVES . Method B use d the same tool described above to estimate the upstream impacts for HD pickups and vans. Updates and enhancements to the GREET model assumptions include updated crude oil and gasoline transport emission factors that account for recent EPA emission standards and modeling, such as accounting for impacts of fuel requirements on vapor emissions from storage and transport. In addition, GREET does not include air toxics. Thus, emission factors for the following air toxics were added: benzene, 1,3 -butadiene, formaldehyde, acetaldehyde, and acrolein. These upstream toxics emission factors were calculated from the 200 5 National Emissions Inventory

(NEI), a risk and technology review for petroleum refineries, sp eciated emission profiles in EPA's SPECIATE database, or the Mobile Source Air Toxics rulemaking (MSAT) inventory

for benzene; these pollutant tons were divided by refinery energy use or gasoline distribution quantities published by the DOE Energy

Information Administration (EIA) to get emission factors in terms of grams per million BTU of finished gasoline and diesel. These updates are consistent with those used for the upstream analysis included in the LD GHG rulemaking and HD GHG Phase 1 . The actual calculation of the emission inventory impacts of the decreased gasoline and diesel production is done in EPA's tool for upstream emission impacts. 13

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5 - 12 

### 5.3.2 **Calculation of Downstream**  **Emissions 5.3.2.1**  **Model inputs and Assumptions for the Less Dynamic Reference Case** The less dy

namic reference case (identified as Alternative 1a in Section X of the preamble and Chapter 11 of the draft RIA) , a “no action” alternative, functions as one the baseline s against which the impacts of the proposed standards can be evaluated and includes the impact of HD GHG Phase 1 , but generally assumes that fuel efficiency and GHG emission standards are not improved beyond the required 2018 model year levels. However, the less dy namic reference case projects some improvement s in the efficiency of the box trailers pulled by combination tractors due to increased penetration of aerody namic technologies and low rolling resistance tires attributed to both EPA’s SmartWay Transport Partnership and California Air Resources Board’s Tractor- Trailer Greenhouse Ga s regulation , as described in Section IV of the preamble . For other HD vehicle sectors, no market- driven improvement in fuel efficiency was assumed. For HD pickups and vans, the CAFE model was applied in a manner that assumes manufacturers would only add fuel - saving technology as needed to continue complying with Phase 1 standards. MOVES2014 defaults were used for all other parameters to estimate the less dy namic reference case emissions inventories. For the aerodynamic drag and tire rolling resistance coefficients of combination tractor- trailers and vocational vehicles, default MOVES values for each MOVES source/vehicle ty pe were used that represent a fleet -wide adoption of HD GHG Phase 1. The less dy

namic reference case assumed the MOVES2014 default vehicle population and vehicle miles traveled (VMT) . 14 

### The growth in vehicle populations and miles traveled in MOVES2014 is based on the relative annual VMT growth from AEO2014 Earl y Release for model years 2012 and later. 15 

### For extended idling emission inventories, the MOVES2014 default auxiliary

power unit (APU) penetration rates were used. These rates assume that 30 percent of all combination long -haul tractors model year 2010 and later use an APU during extended idling. B 

### 5.3.2.2 **Model inputs and Assumptions for the More Dynamic Reference Case**  The more dynamic reference case (identified as Alternative 1b in Section X of the preamble and Chapter 11 of the draft RIA), also includes the impact of Phase 1 and generall y assumes that fuel efficiency and GHG emission standards are not improved beyond the required 2018 model year levels. However, for this case, the agencies assume market forces would lead to additional fuel efficiency improvements for tractors and trailers. These additional assumed improvements are d escribed in Section X of the preamble. No additional fuel efficiency improvements due to market forces were assumed for vocational vehicles. For HD pickups and vans, the agencies applied the CAFE model using the input assumption that manufacturers having achieved compliance with Phase 1 standards would continue to apply technologies for B The agencies assessed the current level of automatic engine shutdown and idle reduction technologies used by the tractor manufacturers to comply with the 2014 model year CO 2 and fuel consumption standards. To date, the manufacturers are meeting the 2014 model year standards without the use of this technology. Therefore, the agencies are reverting the baseline APU adoption rate back to 30 percent, the value used in the HD GHG Phase 1 baseline.

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5 - 13 which increased purchase costs would be “paid back” through corresponding fuel savings within the first six months of vehicle operation. The agencies conducted the MOVES anal ys is of this case in the same manner as for the less dyn amic reference case. 

### 5.3.2.3 **Model Inputs and Assumptions for the Control Case**  The control case (identified as Alternative 3 in Chapter 11 of the draft RIA) represents the agencies’ proposed fuel efficiency and GHG standards for HD engines, HD pickup trucks and vans, Class 2b through Class 8 vocational vehicles, Class 7 and 8 combination tractors, and trailers . To account for improvements of engine and vehicle efficiency in vocational vehicles and combination tractor- trailers , EPA developed additional user input data for MOVES runs to estimate the control case inventories . The agencies used the percent reduction in aerodynamic drag and tire rolling resistance coefficient s and absolute changes in average total running weight (gross combined weight) expected from the proposed rules to develop the road load inputs for the control case . For running emissions, the key concept underlying the definition of operating mode in MOVES is s caled tractive power (STP), vehicle speed and vehicle acceleration. 16 

### STP represents the vehicle’s tractive power scaled b y a constant factor. It is calculated using mass of the vehicle and road load factors that include tire rolling resistance, aerodyn amic drag, and fricti on losses in the drivetrain. STP is estimated using the equation below :

scale t

t t t t t 

### f a

mv Cv Bv Av STP 

   3

2 **Equation 5**  **- 1**  

### Where : A = the rolling resistance coefficient [kW  sec/m],

B = the rotational resistance coefficient [kW  sec 2

### /m2 

### ], C = the aerodyn amic drag coefficient [kW  sec 3 

### /m3 

### ], m = mass of individual vehicle [ metric ton], f scale 

### = fixed mass factor, vt 

### = instantaneous vehicle velocity at time t [m/s], a t 

### = instantaneous vehicle acceleration [m/s 2 

### ] The proposed improvements in road load factors would reduce the tractive power exerted by a vehicle to move itself and its cargo . The emissions emitted by heavy- duty

trucks are a function of STP as determined f rom a variety

of data sources. Thus , a reduction in road load factors are expected to result in reduced GHG and non - GHG emissions. The improvements in tire rolling resistance, aerody namic drag, and absolute changes in average vehicle weight

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5 - 14 expected from the technologies which could be used to meet the proposed standards were modified in the “sourceusety pephys ics” table. C 

### For vocational vehicles and tractor- trailers, the agencies also used the percent reduction in CO 2 

### emissions expected from the powertrain and other vehicle technologies not accounted for in the aerodynamic drag and tire rolling resistance in the proposed rules to develop energy inputs for the control case runs. Incontrast, f or HD pickup trucks and vans, the proposed standards were evaluated onl y in terms of the total vehicle reductions in fuel use and CO 2 

### emissions , s ince nearl y all of these vehicles would be certified on a chassis dynamometer . Finally, EPA used an assumed percent penetration of APU use during extended idling, based on the expectation that manufacturers will use APUs to meet the vehicle GHG standard for combination long -haul tractors , as discussed in Section III.D of the preamble . 

### 5.3.2.3.1 Emission R ate and R oad L oad I nputs Both the stringency

and the form of the proposed fuel consumption and CO 2 

### emission standards vary by vehicle category . Accordingl y, the modeling of the proposed standards in MOVES varies b y the vehicle category. For the vocational vehicles and combination tractortrailers, EPA has analyzed the impacts of the proposed standards b y evaluating the technologies applied to the energy

rate s a s well as to the road load inputs . However, the impact s on the HD pickup trucks and van s were estimated onl y in terms of reduction in energy rate s . **5.3.2.3.1.1 Tractor** 

**- Trailers**  

### Similar to the approach used in the HD GHG Phase 1 anal ys is, EPA aggregated the nine tractor subcategories into the two MOVES combination tractor- trailer categories

– short-haul and long - haul . The agencies used sales distribution data from the HD GHG Phase 1 anal ys is and determined the l ong -haul reductions in energy rates and road load factors, based on a sales mix assumption of 80 percent high roof, 15 percent mid roof, and 5 percent low roof sleeper cabs. The short- haul combination tractors were evaluated using a day cab sales distribution assumption of 7 percent Class 7 low roof, 10 percent Class 7 high roof, 40 percent Class 8 low roof, 35 percent Class 8 high roof, and 8 percent vocational tractors , based on the information used in the HD GHG Phase 1 anal ys is . The details of the analyses aggregating the tractor subcategories into MOVES categories using the sales mix assumption described above can be found in the docket. 17 

### The trailer category

encompasses many

ty pes of trailers. As with the tractor category, EP A aggregated the trailer subcategories into two MOVES combination tractor- trailer categories. EPA used a combination of ACT Research’s 2013 factory shipment data 18 

### for trailer distribution by

type and “primary

trip length” information from the U.S. Census’ 2002 Vehicle Inventory and Use Survey 19 

### to distribute each trailer ty pe into l ong - and short-haul categories. EPA applied the trailer market percentages as shown in Table 5 - 20 to determine the trailer impact on the MOVES long - and short- haul combination tractor- trailer categories.

C Class 2b and 3 trucks do not use the STP metric and are regulated, for non - GHG emissions, based on chassis testing (gram per mile basis) rather than engine testing (gram per brake horsepower- hour basis), therefore road load reduc tions are not necessarily expected to result in reduced non- GHG emissions.

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5 - 15 **Table 5**  **- 20**  **Aggregation of Trailer Types into MOVES Combination Tractor -**  **Trailer Categories** TRAILER TYPE Combination Long -Haul Tractor- Trailers Combination Short-Haul TractorTrailers Long Dry Van 55.5% 20.3% Short Dry Van 12.3% 20.2% Long Refrigerated Van 18.2% 2.6% Short Refrigerated Van 5.2% 3.8% Special Purpose Van 0.0% 6.4% Container Chassis 0.2% 1.8% Flatbed 6.9% 10.9% Tank 0.4% 1.5% Other On -Highway Trailers 1.2% 2.7% Off -Road Trailers 0.0% 29.9% 

### Table 5 - 21 describes the improvements in the energy rate expected from the heavy- duty engine, transmission, and driveline technologies which could be applied to meet the proposed tractor standards. The percentage reductions from the reference case were applied to the default MOVES energy

rates in the appropriate source bins within MOVES “emissionrate" table. **Table 5**  **- 21**  **Estim ated Reductions in En**  **ergy Rate**  **s for**  **th e**  **Proposed Standards**  **for Tractor -**  **Trailers** VEHICLE TYPE FUEL MODEL YEARS REDUCTION FROM REFERENCE CASE Long -haul TractorTrailers Diesel 2018 - 2020 1.3% 2021 - 2023 5.2% 2024 - 2026 9.7% 2027+ 10.4% Short -haul TractorTrailers D Diesel 2018 - 2020 0.9% 2021 - 2023 5.0% 2024 - 2026 9.5% 2027+ 10.4% 

### Table 5 - 22 contains the improvements in tire rolling resistance, coefficient of drag, and weight reductions expected from the technologies which could be used to meet the proposed standards for combination tractor- trailers. The percentage reductions in tire rolling resistance and drag coefficient s and the absolute changes in average vehicle weight were modified in the “sourceusety

pephysics” table.

D Vocational tractors are included in the short- haul tractor segment.

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5 - 16 **Table 5**  **- 22**  **Estim ated Reductions in Road Load Factors**  **for the Proposed**  **St andards**  **for Tractor -**  **Trailers** VEHICLE TYPE MODEL

YEARS REDUCTION IN

TIRE ROLLING RESISTANCE COEFFICIENT REDUCTION IN

AERODYNAMIC DRAG COEFFICIENT WEIGHT REDUCTION (LB) A Combination Long haul TractorTrailers 2018 - 2020 5. 5 % 5.1% - 131

2021 - 2023 9.8% 15.3% - 199 2024 - 2026 15.7% 20.5% - 246 2027+ 17.9 % 26.9% - 304 Combination S hort haul TractorTrailers E 2018 - 2020 4.0 % 1.6 % -4 1

2021 - 2023 10.5 % 9.3% - 79 2024 - 2026 13.9 % 12.3 % - 100 2027+ 17.6% 15.9% - 127 Note: a Negative weight reductions reflect an expected weight increase as a byproduct of the other vehicle and engine im provements. 

### In addition, the projected use of auxiliary power units (APU) during extended idling , shown below in Table 5 - 23 , was included in the modeling for the long -haul combination tractortrailers b y modif

ying the “hotellingactivitydistribution” table in MOVES . **Table 5**  **- 23**  **Assumed APU Use during Extended Idling for Com bination**  **Long -**  **haul Tractor** **- Trailers** 

VEHICLE TYPE MODEL

YEARS APU

PENETRATION Combination Long -Haul Trucks a 2010 - 2020 30%

2021 - 2023 80% 2024+ 90% Note: a T he assumed APU penetration remains constant for model years 2024 and later. **5.3.2.3.1.2 Vocational**  **Vehicles** 

### Similar to the approach for tractor- trailers, EPA aggregated the nine vocational vehicle subcategories into each of the seven MOVES vehicle ty pes. F 

### The energy

rate inputs were derived b y appl ying the anticipated levels of engine, axle, transmission, and idle reduction technologies equall y across all weight classes and vehicle types. Each of these technology packages is described in Chapter 2 of the draft RIA. The differences between gas oline and diesel vocational vehicles in energy rate reduction from the reference case s , shown in Table 5 - 24 , are due to the differences in anticipated engine - level technology packages, as described in Chapter 2 of the draft RIA.

E Vocational tractors are included in the short- haul tractor segment. F Seven MOVES vehicle types for vocatio nal vehicles are intercity bus, transit bus, school bus, refuse truck, single unit short- haul truck, single - unit long -haul truck, and motor home.

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5 - 17 The percentage reductions from the reference case were applied to the default MOVES energy rates in the appropriate source bins within MOVES “emissionrate" table. **Table 5**  **- 24**  **Estim ated Reductions in En**  **ergy Rates**  **for th**  **e Proposed**  **Standards for Vocational Vehicle**  **s** VEHICLE TYPE FUEL MODEL YEARS REDUCTION FROM

REFERENCE CASE Single -Frame Vocational G Diesel & CNG 2021 - 2023 5.3% 2024 - 2026 8.9% 2027+ 13.3% Gasoline 2021 - 2023 3.3%

2024 - 2026 5.4% 2027+ 10.3% 

### The agencies used MOVES population data for new vehicles expected to be sold in 2018 for each weight class, as well as assumptions about their distribution among the three new vocational vehicle duty cycles. This population allocation is shown in Table 5 - 25 .

**Table 5**  **- 25**  **Vocational Vehicle Types and Population Allocation** VEHICLE TYPE RURAL MULTI -PURPOSE URBAN Short Haul Straight Truck 35% 60% 5% Long Haul Straight Truck, Motor Home, Intercity Bus 100% 0% 0% School Bus 0% 100% 0% Transit Bus 0% 75% 25% Refuse 0% 0% 100% All Class 4 - 5 23% 21% 2% All Class 6 - 7 15% 19% 1% All Class 8 7% 8% 4% 

### Using these population distribution estimates and the technology application rates described in Chapter 2 of the draft RIA , EPA derived the levels of improvements in tire rolling resistance and weight reduction. Table 5 - 26 contains the improvements in tire rolling resistance, coefficient of drag, and weight reductions expected from the technologies which could be used to meet the proposed standards for vocational vehicles. The percentage red uctions in tire rolling resistance and drag coefficient s and the absolute changes in average vehicle weight were modified in the

G Vocational vehicles modeled in MOVES include heavy heavy- duty, medium heavy- duty, and light heavy- duty vehic les. However, for light heavy- duty vocational vehicles, class 2b and 3 vehicles are not included in the inventories for the vocational sector. Instead, all vehicles with GVWR less than 14,000 lbs were modeled using the energy rate reductions described be low for HD pickup trucks and vans. In practice, many manufacturers of these vehicles choose to average the lightest vocational vehicles into chassis - certified families (i.e., heavy- duty pickups and vans).

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5 - 18 “sourceusety

pephysics” table in MOVES . The analyses used to develop the MOVES inputs for vocational vehicles, described above, can be found in the docket. 20 **Table 5**  **- 26**  **Estim ated Reductions in Road Load Factors**  **for the Proposed**  **Standards for Vocational Vehicles**  VEHICLE TYPE MODEL

YEARS REDUCTION IN T IRE

ROLLING RESISTANCE COEFFICIENT REDUCTION IN AERODYNAMIC DRAG COEFFICIENT WEIGHT REDUCTION (LB) Intercity B uses 2021 - 2023 6.5% 0% 0

2024 - 2026 9.2% 0% 0 2027+ 16.5% 0% 0 Transit B uses 2021 - 2023 0% 0% 0

2024 - 2026 2.9% 0% 0 2027+ 3.0% 0% 0 School B uses 2021 - 2023 0% 0% 0

2024 - 2026 2.9% 0% 0 2027+ 4.0% 0% 0 Refuse Trucks 2021 - 2023 0% 0% 20

2024 - 2026 2.9% 0% 20 2027+ 3.0% 0% 25 Single Unit S hort -haul Trucks 2021 - 2023 4.8% 0% 5.8

2024 - 2026 8.3% 0% 5.8 2027+ 13.0% 0% 7 Single Unit L ong -haul Trucks 2021 - 2023 6.5% 0% 20

2024 - 2026 9.2% 0% 20 2027+ 16.5% 0% 25 Motor H omes 2021 - 2023 3.0% 0% 0

2024 - 2026 6.2% 0% 0 2027+ 7.4% 0% 0 **5.3.2.3.1.3 Heavy** **-**

**Duty Pickup Trucks and Vans**  

### As explained above , the agencies used both DOT’s CAFE model and EPA’s MOVES model, using anal ytical Method A and B, respectively, to project fuel consumption , GHG and non - GHG emissions impacts resulting from the proposed standards for HD pickups and vans, including downstream vehicular emissions as well as emissions from upstream processes related to fuel production, distribution, and delivery .

**5.3.2.3.1.3.1 Method A for HD Pickups and Vans**  

### For Method A, the CAFE model calculated fuel consumption rates, then calculate d vehicular CO 2 

### emissions from the fuel consumption based on fuel properties (density and carbon content). It also applies per- mile emission factors from MOVES to estimated VMT (for each regulatory

alternative, adjusted to account for the rebound effect) in order to calculate vehicular CH4 

### and N2 

### O emissions (as well, as discussed below, of non- GHG pollutants), and applies pergallon upstream emission factors from GREET in order to calculate upstream GHG (and nonGHG) emissions.

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5 - 19 Consistent with HD GHG Phase 1 approach, the proposed standards for HD pickups and vans are established as a function of the vehicle work factor, a metric unique to this segment which is calculated based on the vehicle capabilities (i.e., payload, towing and four- wheel drive). As proposed, the work - factor-based standards would increase in stringency by 2. 5 percent per ye ar , starting in MY 2021 until they reach the final level of the proposed standards in MY 2027. The standards define targets specific to each vehicle model, but no vehicle is required to meet its target; instead, the production-weighted averages of the vehicl e - specific targets define average fuel consumption and CO 2 

### emission rates that a given manufacturer’s overall fleet of produced vehicles is required to achieve. The standards are specified separately for gasoline and diesel vehicles, and vary

with work fa ctor. Work factors could change, and today’s anal ys is assumes that some applications of mass reduction could enable increased work factor in cases where manufacturers could increase a vehicle’s rated payload and/or towing capacity . Therefore, average required levels will depend on the mix of vehicles and work factors of the vehicles produced for sale in the U.S., and since these can only be estimated at this time, average required and achieved fuel consumption and CO 2 

### emission rates are subject to uncertainty . Between today ’s notice and issuance of the ensuing final rule, the agencies intend to update the market forecast (and other inputs) used to anal yz e HD pickup and van standards, and expect that doing so will lead to different estimates of required and achieved fuel consumption and CO 2 

### emission rates (as well as different estimates of impacts, costs, and benefits). The following four tables present stringency increases and estimated required and achieved fuel consumption and CO 2 

### emission rates for the two No Action Alternatives (Alternative 1a and 1b) and the proposed standards defining the Preferred Alternative. Stringency

increases are shown relative to standards applicable in model year 2018 (and through model year 2020). As mathematical functions, the standards themselves are not subject to uncertainty. By

2027, they

are 16.2 percent more stringent (i.e., lower) than those applicable during 2018 - 2020. The DOT’s CAFE model estimate that, by model 2027, the proposed standards could reduce average required fuel consumption and CO 2 

### emission rates to about 4.86 gallons/100 miles and about 458 grams/mile, respectivel y. The model further estimate that average achieved fuel consumption and CO 2 

### emission rates could correspondingl y be reduced to about the same levels. If, as represented b y Alternative 1b, manufacturers would, even absent today ’s proposed standards, voluntarily make improvements that pay back within six months, these model year 2027 levels are about 13.5 percent lower than the agencies estimate could be achieved under the Phase 1 standards defining the No Action Alternative. If, as represented b y Alternative 1a, manufacturers would, absent today ’s proposed standards, only appl y technology as required to achieve compliance, these model ye ar 2027 levels are about 15 percent lower than the agencies estimate could be achieved under the Phase 1 standards. As indicated below, the agencies estimate that these improvements in fuel consumption and CO 2 

### emission rates would build from model year to mo del year, beginning as soon as model year 2017 (insofar as manufacturers may

make anticipatory

improvements if warranted given planned produce cadence).

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5 - 20 **Table 5**  **- 27**  **Stringency of HD Pickup and Van Standards, E stimated Average Required and Achieved Fuel** 

**Consumption Rates for Method A**  **, R** **elative to Alternative 1**  **b a**  MODEL YEAR STRINGENCY

(VS. 2018) AVE. REQUIRED FUEL C ONS. (GAL./100 MI.) AVE. ACHIEVED FUEL C ONS. (GAL./100 MI.) No Action Proposed Reduction No Action Proposed Reduction 2014 MYs 2014 -

2020 Subject to Phase 1 Standards 6.41 6.41 0.0% 6.21 6.21 0.0% 2015 6.41 6.41 0.0% 6.12 6.12 0.0% 2016 6.27 6.27 0.0% 6.15 6.15 0.0% 2017 6.11 6.11 0.0% 5.89 5.88 0.2% 2018 5.80 5.80 0.0% 5.75 5.70 0.8% 2019 5.78 5.78 0.0% 5.72 5.68 0.7% 2020 5.78 5.78 0.0% 5.69 5.64 0.8% 2021 2.5% 5.77 5.64 2.2% 5.63 5.42 3.8% 2022 4.9% 5.77 5.50 4.7% 5.63 5.42 3.8% 2023 7.3% 5.77 5.38 6.8% 5.63 5.28 6.3% 2024 9.6% 5.77 5.25 9.0% 5.63 5.23 7.1% 2025 11.9% 5.77 5.12 11.4% 5.63 4.99 11.5% 2026 14.1% 5.77 4.98 13.7% 5.63 4.93 12.5% 2027 16.2% 5.77 4.86 15.8% 5.62 4.86 13.7% 2028* 16.2% 5.77 4.86 15.8% 5.62 4.86 13.7% 2029* 16.2% 5.77 4.86 15.8% 5.62 4.85 13.7% 2030* 16.2% 5.77 4.86 15.8% 5.62 4.85 13.7% Notes: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1 *Absent further action, standards assumed to continue unchanged after model year 2027.

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5 - 21 **Table 5**  **- 28**  **Stringency of HD Pickup and Van Standards, Estimated Average Required and Achieved CO 2**  **Emission Rates for Method A, Relative to Alternative**  **1 b**  **a** MODEL YEAR STRINGENCY

(VS. 2018) AVE. REQUIRED CO 2 RATE (G./MI.) AVE. ACHIEVED CO 2 RATE (G./MI.) No Action Proposed Reduction No Action Proposed Reduction 2014 MYs 2014 -

2020 Subject to Phase 1 Standards 602 602 0.0% 581 581 0.0% 2015 608 608 0.0% 578 578 0.0% 2016 593 593 0.0% 580 580 0.0% 2017 578 578 0.0% 556 554 0.2% 2018 548 548 0.0% 543 538 0.8% 2019 545 545 0.0% 539 535 0.7% 2020 545 545 0.0% 536 532 0.8% 2021 2.5% 544 532 2.2% 530 510 3.8% 2022 4.9% 544 519 4.7% 530 510 3.8% 2023 7.3% 544 507 6.8% 530 496 6.4% 2024 9.6% 544 495 9.1% 530 492 7.2% 2025 11.9% 544 482 11.3% 530 470 11.3% 2026 14.1% 544 470 13.6% 530 465 12.3% 2027 16.2% 544 458 15.8% 529 458 13.4% 2028* 16.2% 544 458 15.8% 529 458 13.4% 2029* 16.2% 544 458 15.8% 529 458 13.5% 2030* 16.2% 544 458 15.8% 529 458 13.5% Notes: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1 *Absent further action, standards assumed to continue unchanged after model year 2027.

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5 - 22 **Table 5**  **- 29**  **Stringency of HD Pickup and Van Standards, Estimated Average Required and Achieved Fuel**

**Consumption Rates for Method A, Relative to Alternative**  **1 a**  **a** MODEL YEAR STRINGENCY

(VS. 2018) AVE. REQUIRED FUEL C ONS. (GAL./100 MI.) AVE. ACHIEVED FUEL C ONS. (GAL./100 MI.) No Action Proposed Reduction No Action Proposed Reduction 2014 MYs 2014 -

2020 Subject to Phase 1 Standards 6.41 6.41 0.0% 6.21 6.21 0.0% 2015 6.41 6.41 0.0% 6.12 6.12 0.0% 2016 6.27 6.27 0.0% 6.15 6.15 0.0% 2017 6.11 6.11 0.0% 5.89 5.87 0.3% 2018 5.80 5.80 - 0.1%** 5.75 5.70 0.9% 2019 5.78 5.78 0.0% 5.73 5.68 0.8% 2020 5.78 5.78 0.0% 5.73 5.68 0.8% 2021 2.5% 5.77 5.64 2.3% 5.72 5.44 4.8% 2022 4.9% 5.77 5.50 4.7% 5.72 5.44 4.8% 2023 7.3% 5.77 5.38 6.8% 5.72 5.29 7.6% 2024 9.6% 5.77 5.25 9.1% 5.72 5.23 8.5% 2025 11.9% 5.77 5.12 11.4% 5.72 4.98 12.9% 2026 14.1% 5.77 4.98 13.7% 5.72 4.94 13.6% 2027 16.2% 5.77 4.86 15.8% 5.72 4.87 14.9% 2028* 16.2% 5.77 4.86 15.8% 5.72 4.87 14.9% 2029* 16.2% 5.77 4.86 15.8% 5.72 4.86 15.0% 2030* 16.2% 5.77 4.86 15.8% 5.72 4.86 15.0% Notes: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1 *Absent further action, standards assumed to continue unchanged after model year 2027. **Increased work factor for some vehicles produces a slight increase in average required fuel consumption.

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5 - 23 **Table 5**  **- 30**  **Stringency of HD Pickup an d Van Standards, Estimated Average Required and Achieved CO**  **2 Emission Rates**  **for Method A, Relative to Alternative 1**  **a a**  MODEL YEAR STRINGENCY

(VS. 2018) AVE. REQUIRED CO 2 RATE (G./MI.) AVE. ACHIEVED CO 2 RATE (G./MI.) No Action Proposed Reduction No Action Proposed Reduction 2014 MYs 2014 -

2020 Subject to Phase 1 Standards 602 602 0.0% 581 581 0.0% 2015 608 608 0.0% 578 578 0.0% 2016 593 593 0.0% 580 580 0.0% 2017 578 578 0.0% 556 554 0.3% 2018 548 548 - 0.1%** 543 538 0.9% 2019 545 546 - 0.1%** 539 535 0.8% 2020 545 545 - 0.1%** 539 535 0.8% 2021 2.5% 544 532 2.2% 538 512 4.9% 2022 4.9% 544 519 4.7% 538 512 4.9% 2023 7.3% 544 507 6.8% 538 497 7.7% 2024 9.6% 544 495 9.1% 538 492 8.6% 2025 11.9% 544 482 11.4% 538 470 12.7% 2026 14.1% 544 470 13.6% 538 466 13.4% 2027 16.2% 544 458 15.8% 538 459 14.7% 2028* 16.2% 544 458 15.8% 538 459 14.7% 2029* 16.2% 544 458 15.8% 538 459 14.8% 2030* 16.2% 544 458 15.8% 538 459 14.8% Notes: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1 *Absent further action, standards assumed to continue unchanged after model year 2027. **Increased work factor for some vehicles produces a slight increase in the average required CO 2 emission rate. 

### While the above tables show the agencies’ estimates of average fuel consumption and CO 2 

### emission rates manufacturers might achieve under today ’s proposed standards, total U.S. fuel consumption and GHG emissions from HD pickups and vans will also depend on how many of thes e vehicles are produced, and how they are operated over their useful lives. Relevant to estimating these outcomes, the CAFE model applies vintage - specific estimates of vehicle survival and mileage accumulation, and adjusts the latter to account for the rebound effect. This impact of the rebound effect is specific to each model year (and, underlying, to each vehicle model in each model ye ar), varying with changes in achieved fuel consumption rates. For additional details, see Chapter 2 of the draft RIA.

**5.3.2.3.1.3.2 Method B for HD Pickups and Vans**  

### For Method B, MOVES model was used to estimate fuel consumption and GHG emissions for HD pickups and vans. MOVES evaluated the proposed standards for HD pickup trucks and vans in terms of grams of CO 2 

### per mile or gallons o f fuel per 100 miles. Since nearl y all HD pickup trucks and vans are certified on a chassis dy namometer, the CO 2 

### reductions for these vehicles were not represented as engine and road load reduction components, but rather as total vehicle CO 2 

### reductions. The stringency increases relative to the Phase 1 standards for HD pickup trucks and vans ( Table 5 - 32 ) were modified in the “emissionrate” table in MOVES.

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5 - 24 **Table 5**  **- 31**  **Estim ated Total Vehicle CO**  **2 Reductions for the Proposed Standards**  **and In -**  **Use Emissions for**  **HD Pickup Trucks and Vans in Method B**  **a** VEHICLE TYPE FUEL MODEL YEAR CO 2 REDUCT ION FROM REFERENCE CASE HD Pickup Trucks and Vans Gasoline

and Diesel 2021 2.50%

2022 4.94% 2023 7.31% 2024 9.63% 2025 11.89% 2026 14.09% 2027+ 16.24% Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1 

### 5.3.2.3.2 VMT I

nputs The “HPMSVty

pe ” table in MOVES was modified to reflect the VMT rebound (VMT rebound is described in more detail in Chapter 8.3 of the draft RIA) . This table estimated VMT values for all calendar years . For the control case, the absolute VMT for vocational vehicle and combination tractor- trailer w ere increased from the reference case s by 1.83 percent , and 0.79 percent , respectively, to reflect the VMT rebound. Since VMT is applied by calendar year and not by model year, post- processing of the results were performed to ensure that only the model ye ars affected by

the program experienced VMT rebound

– the results from the reference case s were used in the control case inventories for model years not affected by the proposed rules . For HD pickups and vans, Method A used the CAFE model which simulates VMT in a dy namic fashion that responds to changes in vehicle fuel economy and fuel prices and adjust s the marginal VMT of each vehicle model, at every age (so in each calendar ye ar). In general, the more stringent alternatives considered lead to larger improvements in fuel economy and , thus, a greater number of vehicle miles traveled as a result of the rebound effect . In the CAFE model, the rebound effect represents a sy mmetric driver of changes to VMT; if the per- mile price of driving declines relative to today (either from improvements in vehicle fuel economy or declines in fuel prices), VMT increases b y the amount of the rebound effect, conversely, if the per- mile price of driving increases relativ e to today (due to increases in the price of fuel), VMT will decline b y the amount of the rebound effect. In Method B, the VMT rebound effect was modeled using the MOVES model which assumed an increase in VMT from the reference levels by 1.18 percent. 

### 5.3.3 **Cal culation of Upstream Emissions** 

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5 - 25 The term "upstream emissions" refers to air pollutant emissions generated from all crude oil extraction, transport, refining, and finished fuel transport, storage, and distribution ; this includes all stages prior to the final filling of vehicle fuel tanks at retail service stations. Additionally, it includes the production of renewable fuels and transportation of such fuel, either separately or mixed with conventional fuels. As described in Section 5.3.1 , the decreased volumes of the crude based fuels and the various crude production and transport emission factors from GREET were used to estimate the net impact of fuel use changes on upstream emissions . The anal ys is for this proposed rulemaking assumes that all changes in volumes of fuel used affect only gasoline and diesel, with no effects on use of ethanol, biodiesel or other renewable fuels. The production and transport of these renewable fuels, although unchanged in volume for this anal ys is, are still accounted for in the total inventory

in this proposed rulemaking. Although impacts to agriculture related to renewable fuels and the associated transport of these feedstocks were originally included in the RFS2 rulemaking, the effects to these sectors from the proposed regulations would be minimal and have therefore excluded them from this anal ysis. The agencies recognize the unique GHG emission characteristics associated with bi ofuels, and specificall y that in the context of biofuels, “upstream emissions ” include not only GHG emissions, but also any net biological sequestration that takes place. When considered on a lifecycle basis (including both tailpipe and upstream emissions ), the net GHG emission impact of individual biofuels can vary significantl y from both petroleum -based fuels and from one biofuel to another. EPA’s Renewable Fuel Standard (RFS) program, as modified by EI SA, examined these differences in lifecycle emissions in detail. For example, EPA found that with respect to aggregate lifecycle emissions including non- tailpipe GHG emissions (such as feedstock growth, transportation, fuel production, and land use), lifecycle GHG emissions in 2022 for biodiesel from soy, using certain advanced production technologies, are about 50 percent less than diesel from petroleum. Non - GHG fuel production and distribution emission impacts of the program were estimated in conjunction with the development of lifecycle GHG emission impacts, and the GHG emission inventories discussed above. The basic calculation is a function of fuel volumes in the anal ys is year and the emission factors associated with each process or subprocess. It relies partially on the GREET model, but takes adv antage of additional information and models to significantl y strengthen and expand on the GREET anal ys is , as discussed in Section 5.3.1 . The details of the assumptions, data sources, and calculations that were used to estimate the emission impacts presented here can be found in the docket memo, “ Calculation of Upstream Emi ssions for the GHG Vehicle Rule,” initially created for use in the LD GHG rulemaking. 21 

### The ag encies note that to the extent future policy decisions involve upstream emissions, the agencies will need to consider the unique emission characteri stics associated with biofuels. More broadl y, the agencies recognize that biofuels, including biodiesel, wi ll play an important role in reducing the nation’s dependence on foreign oil, thereb y increasing domestic energy security . The volumes of renewable fuels are defined by the RFS2 standards as well as the Annual RFS rulemakings, and are projected using AEO2 014. The volumes of renewable fuel for these standards remain in place regardless of overall volume of fuel affected by this proposed rulemaking. Therefore , we have assumed that the effect of this proposal on biofuels agriculture and transportation of raw agricultural goods would be minimal and excluded it from this analysis.

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5 - 26 As described earlier, the agencies estimated the impact of the proposed rules on upstream using the downstream fuel consumption reductions predicted b y MOVES for vocational vehicle s and tractor- trailers. For HD pickups and vans, parallel and complementary anal ys es of estimating the emissions from upstream processes were conducted using the fuel consumption estimates from DOT’s CAFE model and EPA’s MOVES model, using Method A and B , respectivel y. As note d previously, these anal ys es corroborate each other’s results. 

### 5.3.4 **Calculation of HFC Emissions**  **H** 

### EPA is propos ing new air conditioning (A/C) leakage standards for vocational vehicles to reduce HFC emissions. The Vintaging M odel, developed by EPA Office of Atmospheric programs, produces HFC inventories for several categories of stationary and mobiles sources. However, it does not include air conditioning s ys tems in medium and heavy- duty truck s within its inventory

calculations. F or this proposal , we conducted an anal ys is based on the inputs to the Vintaging M odel and the inputs to the MOVES analysis discussed in Chapter 5.3.2 above. The general equation for calculating HFC emissions follows: HFC emissions Year x 

### = A/ C Systems Year x 

### x Average Charge Size x HFC loss rate We determined the number of functioning A/C systems in each year based on the projected sales of vehicles, the fraction o f vehicles with A/C systems, and the average lifetime of an A/C system. Sales were drawn from the MOVES analysis and we assumed that every vehicle had a functioning A/C system when sold . The Vintaging Model assumes that all light- duty passenger vehicle A/C systems (in the U.S.) last exactly 12 years. I 

### Inthe absence of other information, we assumed that heavy- duty vehicles A/C systems last for the same period of time as light- duty vehicles. Light, medium and heavy- duty vehicles use largely

the same components in their air conditioning systems (sometimes from the same suppliers) , which would indicate similar periods of durability . The charge size was determined using the Minnesota refrigerant leakage database. 22 

### EPA sorted the data based on A/C charg e size and evaluated only the largest 25 percent of A/C systems to be more representative of HD s ys tems . The average charge size is 1,025 grams of refrigerant. Due to the similarity

in system design, we assumed that the light- duty vehicle emission rate in the Vintaging M odel was applicable to the current anal ys is, as shown in Table 5 - 32 . The Vintaging Model assumes that losses occur from three events: leak, service, and disposal. Although vehicle A/C systems are serviced during discrete events and not usually every year, emissions from those events are averaged over the lifetime of the A/C system in the Vintaging

H The U.S. has submitted a proposal to the Montreal Protocol which, if adopted, would phase - down production and consumption of HFCs. I This is in agreement with the IPCC report IPCC/TEAP 2005 Safeguarding the Ozone Layer and the Global Climate System

– Issues Related to Hydrofluorocarbons and Perfluorocarbons, which indicates lifetimes (worldwide) of 9 to 12 years.

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5 - 27 model . Leak and service emissions are considered “annual losses” and are applied every year; disposal is considered an “end of life loss” and is applied only once for each vintage of vehicles. J **Table 5**  **- 32**  **Annual In -**  **use Vehicle HFC134a Em ission**  **Rate from Vintaging Model** 

KI ND OF LOSS LOSS FRACTION Leakage 8% Maintenance /Servicing 10% End of Life 43% 

### The Vintaging M odel assumes that charge loss is replaced every year; i.e . , assuming an 18 percent rate of charge loss, a vehicle with a charge of 1 , 00 0 grams would lose a constant rate of 18 0 grams per ye ar. While this loss rate is not representative of any single given vehicle, it is assumed accurate for the fleet as a whole. O ther emissions, such as fugitive emissions at a production facility, leaks from cylinders in storage, etc., are not explicitly modeled, but such emissions are accounted for within the average annual loss rate. EPA’s anal ys is of the Minnesota database of MY 2010 vehicles suggests that many of the modeled vehicles likel y contain some of the technology required to meet the leakage standard, and as a consequence are leaking less. We assume that these improvements are independent of EPA regulation, rather than a preemptive response to regulation. Consequently, this rulemaking does not take credit for these emission reductions. Based on the Minnesota database, we determined that it is possible to reduce the HFC emissions from these vehicles on average b y 13 percent. EPA calculated this based on the assumption that vehicles currentl y in the fleet which meet the MY 2014 standard would not make any additional improvements to reduce leakage. We also assumed that the systems which currentl y have leakage rates above the standard will reduce their leakage to the level of the standard. We then applied the 13 perc ent reduction to the baseline 18 percent leakage rate to develop a 15 .6 percent leakage rate for MY 2014 and later vehicles to determine the reduction in emission rate which should be credited to this rulemaking . K 

### We calculated our emission reductions based on the difference between the baseline case of 2010 vehicle technology (discussed above) and the control scenario where the loss prevention technology

has been applied to 100 percent of the new vocational vehicles starting in 20 21 model year, as would be required b y the proposed standards.

J The U.S. EPA has reclamation requirements for refrigerants in place under Title VI of the Clean Air Act. K Using 18 percent as the base emission rate may overstate the net emission reductions. However, recent number from the ERG Report to CARB studying the leakage rate of heavy - duty vehicles are actually much larger (range of near 0 to 150 percent annually), and places an 18 percent annual loss rate well within the literature. However, (a) the net impact is very small, (b) these numbers have significant uncertainty, and (c) it is unclear w hat the appropriate mo dification would be.

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5 - 28 Total HFC reductions are 177 metric tons over the MY 20 21 baseline A/C system in 2035 and 210 metric tons in 2050. This is equivalent to a reduction of 253,118 metric tons of CO 2 

### e q emissions in 2035 ; and 299,590 metric tons CO 2 

### e q in 2050. L 

### EPA reviewed a study conducted b y the Eastern Research Group (ERG) of R134a leaks in h eavy- d

uty v ehicles to California Air Resource s Board. 23 

### The study included a total of 70 medium - and heavy- d

uty vehicles and off

-road equipment ; of which 18 of the samples were HD tractors ranging between 1990 and 2008 model years. The mobile air conditioning capacity in the tractors ranged between 1,080 grams to 1,950 grams. The study measured HFC leakage during sample times which ranged between 0.3 and 0.6 years. ERG then calculated an annualized in -use leakage rate with an assumed linear projection of measured leak rates to annual leak rates, which may

be an over- estimate. The annualize leakage rate for tractors ranged between nearl y 0 to nearly 1.5 grams leakage per gram of MAC capacity. These leakage rates did not include other leakage sources such as maintenance or end of life recovery . ERG found that the average of all MD and HD trucks and equipment which were 2006 MY or newer had an average leakage of 103 grams of R134a per year. Based on these results, the agency believes that our estimates for HFC reductions may understate the benefits of the proposed program . The agency will continue to analyze this and other studies that may be conducted in the future. 

## 5.4 **Greenhouse Gas Emission and Fuel Consumption**  **Impacts** The following subsections summarize two slightly different anal ys es of the annual GHG emissions and fuel consumption reductions expected from the proposed standards , as well as the reductions in GHG emissions and fuel consumption expected over the lifetime of each heavyduty vehicle categories. In addition, because the agencies are carefully considering Alternative 4 along with Alternative 3, the preferred alternative, the results from both are presented here for the reader’s reference. Section 5.4.1 shows the impacts of the proposed rules and Alternative 4 on fuel consumption and GHG emissions using the MOVES model for tractor- trailers and vocational vehicles, and the DOT’s CAFE model for HD pickups and vans (Method A), relative to two different reference cases

– less dy namic and more dy

namic. Section 5.4.2 shows the impacts of the proposed standards and Alternative 4 , relative to the less dy namic reference case only, using the MOVES model for all heavy- duty vehicle categories. 

### 5.4.1 **Impacts of the Proposed Rules and Alternative 4 using Analysis Method A 5.4.1.1**  **Calendar Year Analysis** 5.4.1.1.1 D ownstream Impacts The following two tables summarize the agencies’ estimates of HD pickup and van fuel consumption and GHG emissions under the current and proposed standards defining the No Action and Preferred alternatives, respectivel y. The first shows results assuming manufacturers would voluntarily

make improvements that pay back within six months (i.e., Alternative 1b). The second shows results assuming manufacturers would only make improvements as needed to

L Using a Global Warming Potential of 1,430 for HFC - 134a.

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5 - 29 achieve compliance with standards (i.e., Alternative 1a). While underl ying calculations are all performed for each calendar year during each vehicle’s useful life, presentation of outcomes on a model year basis aligns more clearl y with consideration of cost impacts in each model ye ar, and with consideration of standards specified on a model year basis. In addition, the agencies performed explicit analysis of manufacturers’ potential responses to HD pickup and van standards on a model ye ar basis through 2030, and any longer- term costs presented in today ’s notice represent extrapolation of these results absent any underl ying analysis of longer- term technology

prospects and manufacturers’ longer- term product offerings. **Table 5**  **- 33**  **Estim ated Fuel Consumption and GHG Emissions over Useful Life of**  **HD Pickups and Vans**

**Produced in Each Model year for Method A**  **, Relative to Alternative 1b a**  MODEL YEAR FUEL CONSUMPTION (B. GAL.)

OVER FLEET’S USEFUL LIFE GHG EMISSIONS ( MMT CO 2 EQ) OVER FLEET’ S USEFUL LIFE No Action Proposed Reduction No Action Proposed Reduction 2014 9.41 9.41 0.0% 115 115 0.0% 2015 9.53 9.53 0.0% 117 117 0.0% 2016 9.72 9.72 0.0% 119 119 0.0% 2017 9.49 9.47 0.2% 116 116 0.2% 2018 9.26 9.19 0.7% 113 113 0.7% 2019 9.20 9.14 0.7% 113 112 0.7% 2020 9.19 9.12 0.7% 112 112 0.7% 2021 9.10 8.79 3.4% 111 107 3.4% 2022 9.13 8.82 3.4% 112 108 3.4% 2023 9.11 8.59 5.7% 111 105 5.7% 2024 9.32 8.72 6.4% 114 107 6.4% 2025 9.49 8.49 10.5% 116 104 10.4% 2026 9.67 8.56 11.5% 118 105 11.3% 2027 9.78 8.55 12.6% 120 105 12.3% 2028 9.90 8.66 12.6% 121 106 12.3% 2029 10.02 8.75 12.6% 122 107 12.4% 2030 10.03 8.76 12.6% 123 107 12.4% Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1

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5 - 30 **Table 5**  **- 34**  **Estim ated Fuel Consumption and GHG Emissions over Useful Life of**  **HD Pickups and Vans**

**Produced in Each Model year for Method A**  **, Relative to Alternative 1a**  **a** MODEL YEAR FUEL CONSUMPTION (B. GAL.)

OVER FLEET’S USEFUL LIFE GHG EMISSIONS ( MMT CO 2 EQ) OVER F LEET’S USEFUL LIFE No Action Proposed Reduction No Action Proposed Reduction 2014 9.41 9.41 0.0% 115 115 0.0% 2015 9.53 9.53 0.0% 117 117 0.0% 2016 9.72 9.72 0.0% 119 119 0.0% 2017 9.49 9.46 0.3% 116 116 0.3% 2018 9.27 9.19 0.8% 114 113 0.8% 2019 9.20 9.14 0.7% 113 112 0.7% 2020 9.25 9.18 0.7% 113 112 0.8% 2021 9.23 8.82 4.4% 113 108 4.4% 2022 9.26 8.85 4.4% 113 108 4.4% 2023 9.23 8.60 6.9% 113 105 6.9% 2024 9.45 8.72 7.7% 116 107 7.7% 2025 9.62 8.48 11.8% 118 104 11.7% 2026 9.81 8.58 12.5% 120 105 12.3% 2027 9.93 8.57 13.7% 121 105 13.5% 2028 10.05 8.68 13.7% 123 106 13.5% 2029 10.17 8.77 13.7% 124 108 13.5% 2030 10.18 8.78 13.7% 124 108 13.5% Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1 

### To more clearl y communicate these trends visually, the following two charts present the above results graphicall y for Method A , relative to Alternative 1b. As shown, fuel consumption and GHG emissions follow paralle l though not precisely identical paths. Though not presented, charts for anal ys is relative to Alternative 1a would appear sufficientl y similar that differences between Alternative 1a and Alternative 1b remain best communicated by comparing values in the a bove tables.

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5 - 31 **Figure 5**  **- 1**  **Fuel Consumption (b. gal.) over Useful Life of HD Pickups and Vans Produced in Each Model Year**  **for Method A**

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5 - 32 **Figure 5**  **- 2**  **GHG Emissions (** **MMT CO**  **2 eq) over Useful Life of HD Pickups and Vans Produced in Each**  **Model Year for Method A** 

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5 - 33 **Table 5**  **- 35**  **Annual Downstream GHG Emissions Impacts in Calendar Years 2025, 2035 and 2050 by Heavy** ****

**Duty V ehicle Category**  **– Preferred Alternative vs. Alt 1b**  **using Analysis Method A a**  CY VEHICLE

CATEGORY CO 2

(MMT) CH4

(MMT CO 2 EQ) N2 O

(MMT CO 2 EQ) A TO TAL

DOWNSTREAM (MMT CO 2 EQ) 2025 HD Pickups and

Vans - 2.4 0 0 - 2.4 Vocational - 2.4 0 0 - 2.4 Tractor- Trailers - 22.1 - 0.4 0 - 22.4 Total - 26.9 - 0.4 0 - 27.2 2035 HD Pickups and

Vans - 9.4 0 0 - 9.4 Vocational - 11.9 0 0 - 11.9 Tractor- Trailers - 64.7 - 1 0 - 65.6 Total - 86 .0 - 1 0 - 86.9 2050 HD Pickups and

Vans - 11.8 0 0 - 11.8 Vocational - 17.2 0 0 - 17.2 Tractor- Trailers - 92.6 - 1.4 0 - 94 .0 Total - 121.6 - 1.4 0 - 123 .0 Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1 **Table 5**  **- 36**  **Annual Downstream GHG Emissions Impacts in Calendar Years 2025, 2035 and 2050 by Heavy** ****

**Duty Vehicle Category –**  **Preferred Alternative vs. Alt 1a using Analysis Method A**  **a** CY VEHICLE

CATEGORY CO 2

(MMT) CH4

(MMT CO 2 EQ) N2 O

(MMT CO 2 EQ) A TO TAL

DOWNSTREAM (MMT CO 2 EQ) 2025 HD Pickups and

Vans - 2.9 0 0 - 2.9 Vocational - 2.4 0 0 - 2.4 Tractor- Trailers - 22.5 - 0.4 0 - 22.8 Total - 27.7 - 0.4 0 - 28.1 2035 HD Pickups and

Vans - 10.5 0 0 - 10.5 Vocational - 11.9 0 0 - 11.9 Tractor- Trailers - 71.1 - 1 0 - 72.1 Total - 93.6 - 1 0 - 94.6 2050 HD Pickups and

Vans - 13.1 0 0 - 13.1 Vocational - 17.2 0 0 - 17.2 Tractor- Trailers - 103.2 - 1.4 0 - 104.6 Total - 133.5 - 1.4 0 - 134.9 Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1

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5 - 34 **Table 5**  **- 37**  **Annual Downstream GHG Emissions Impacts in Calendar Years 2025, 2035 and 2050 by Heavy** ****

**Duty Vehicle Category –**  **Alternative 4 vs. Alt 1b using Analysis Method A a**  CY VEHICLE

CATEGORY CO 2

(MMT) CH4

(MMT CO 2 EQ) N2 O

(MMT CO 2 EQ) A TO TAL

DOWNSTREAM (MMT CO 2 EQ) 2025 HD Pickups and

Vans - 3.3 0 0 - 3.3 Vocational -4 .0 0 0 -4 .0 Tractor- Trailers - 25.9 - 0.4 0 - 26.2 Total - 33.2 - 0.4 0 - 33.5 2035 HD Pickups and

Vans - 10.3 0 0 - 10.3 Vocational - 12.9 0 0 - 12.9 Tractor- Trailers - 66.7 - 1 0 - 67.7 Total - 89.9 - 1 0 - 90.9 2050 HD Pickups and

Vans - 12.6 0 0 - 12.6 Vocational - 17.3 0 0 - 17.3 Tractor- Trailers - 92.8 - 1.4 0 - 94.2 Total - 122.6 - 1.4 0 - 124 .0 Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1 **Table 5**  **- 38**  **Annual Downstream GHG Emissions Impacts in Calendar Years 2025, 2035 and 2050 by Heavy** ****

**Duty Vehicle Category –**  **Alternative 4 vs. Alt 1a using Analysis Method A a**  CY VEHICLE

CATEGORY CO 2

(MMT) CH4

(MMT CO 2 EQ) N2 O

(MMT CO 2 EQ) A TO TAL

DOWNSTREAM (MMT CO 2 EQ) 2025 HD Pickups and

Vans -4 .0 0 0 -4 .0 Vocational -4 .0 0 0 -4 .0 Tractor- Trailers - 26.2 - 0.4 0 - 26.6 Total - 34.3 - 0.4 0 - 34.6 2035 HD Pickups and

Vans - 11.6 0 0 - 11.6 Vocational - 12.9 0 0 - 12.9 Tractor- Trailers - 73.2 - 1 0 - 74.2 Total - 97.7 - 1 0 - 98.7 2050 HD Pickups and

Vans - 14 .0 0 0 - 14 .0 Vocational - 17.3 0 0 - 17.3 Tractor- Trailers - 103.3 - 1.4 0 - 104.7 Total - 134.6 - 1.4 0 - 136 .0 Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1

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5 - 35 **Table 5**  **- 39**  **Annual Fuel Savings in Calendar Years 2025, 2035 and 2050 by Heavy -** **Duty Vehicle Category**  **– Preferred Alternative vs. Alt 1b using Analysis Method A**  **a** CY VEHICLE CATEGORY DIESEL SAVINGS (BILLION GALLONS) GASOLINE SAVINGS (BILLION GALLONS) 2025 HD Pickups and Vans 0.1 0.1 Vocational 0.2 0 Tractor- Trailers 2.2 0 Total 2.5 0.2 2035 HD Pickups and Vans 0.3 0.7 Vocational 1 .0 0.2 Tractor- Trailers 6.3 0 Total 7.6 0.9 2050 HD Pickups and Vans 0.3 0.9 Vocational 1.4 0.3 Tractor- Trailers 9.1 0 Total 10.8 1.2 Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1 **Table 5**  **- 40**  **Annual Fuel Savings in Calendar Years 2025, 2035 and 2050 by Heavy -** **Duty Vehicle Category**  **– Preferred Alternative vs. Alt 1a using Analysis Method A**  **a** CY VEHICLE CATEGORY DIESEL SAVINGS (BILLION GALLONS) GASOLINE SAVINGS (BILLION GALLONS) 2025 HD Pickups and Vans 0.1 0.2 Vocational 0.2 0 Tractor- Trailers 2.2 0 Total 2.5 0.2 2035 HD Pickups and Vans 0.3 0.8 Vocational 1 .0 0.2 Tractor- Trailers 7 .0 0 Total 8.3 1 .0 2050 HD Pickups and Vans 0.4 1 .0 Vocational 1.4 0.3 Tractor- Trailers 10.1 0 Total 11.9 1.3 Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1

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5 - 36 **Table 5**  **- 41**  **Annual Fuel Savings in Calendar Years 2025, 2035 and 2050 by Heavy -** **Duty Vehicle Category**  **– Alternative 4 vs. Alt 1b using Analysis Method A**  **a** CY VEHICLE CATEGORY DIESEL SAVINGS (BILLION GALLONS) GASOLINE SAVINGS (BILLION GALLONS) 2025 HD Pickups and Vans 0.1 0.2 Vocational 0.3 0.1 Tractor- Trailers 2.5 0 Total 3 .0 0.3 2035 HD Pickups and Vans 0.3 0.8 Vocational 1 .0 0.2 Tractor- Trailers 6.5 0 Total 7.9 1 .0 2050 HD Pickups and Vans 0.4 1 .0 Vocational 1.4 0.3 Tractor- Trailers 9.1 0 Total 10.8 1.3 Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1 **Table 5**  **- 42**  **Annual Fuel Savings in Calendar Years 2025, 2035 and 2050 by Heavy -** **Duty Vehicle Category**  **– Alternative 4 vs. Alt 1a using Analysis Method A**  **a** CY VEHICLE CATEGORY DIESEL SAVINGS (BILLION GALLONS) GASOLINE SAVINGS (BILLION GALLONS) 2025 HD Pickups and Vans 0.2 0.3 Vocational 0.3 0.1 Tractor- Trailers 2.6 0 Total 3.1 0.3 2035 HD Pickups and Vans 0.4 0.8 Vocational 1 .0 0.2 Tractor- Trailers 7.2 0 Total 8.6 1.1 2050 HD Pickups and Vans 0.5 1 .0 Vocational 1.4 0.3 Tractor- Trailers 10.1 0 Total 12 .0 1.3 Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1 

### 5.4.1.1.1 Upstream Impacts

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5 - 37 **Table 5**  **- 43**  **Annual Upstream GHG Emissions Impacts in Calendar Years 2025, 2035 and 2050**  **by Heavy******

**Duty Vehicle Category**  **– Preferred Alternative vs. Alt 1b using Analysis Method A**  **a** CY VEHICLE CATEGORY CO 2

(MMT) CH4

(MMT CO 2 EQ) N2 O

(MMT CO 2 EQ) A TO TAL

UPSTREAM (MMT CO 2 EQ) 2025 HD Pickups and Vans - 0.6 - 0.1 0 - 0.7 Vocational - 0.7 - 0.1 0 - 0.8 Tractor- Trailers - 7 .0 - 0.7 0 - 7.8 Total - 8.4 - 0.9 - 0.1 - 9.3 2035 HD Pickups and Vans - 2.5 - 0.4 - 0.1 - 2.9 Vocational - 3.6 - 0.4 0 -4 .0 Tractor- Trailers - 20.6 - 2.1 - 0.1 - 22.8 Total - 26.6 - 2.8 - 0.2 - 29.7 2050 HD Pickups and Vans - 3.1 - 0.4 - 0.1 - 3.7 Vocational - 5.1 - 0.6 0 - 5.7 Tractor- Trailers - 29.5 - 3 .0 - 0.1 - 32.6 Total - 37.7 -4 .0 - 0.3 -42 .0 Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1 **Table 5**  **- 44**  **Annual Upstream GHG Emissions Impacts in Calendar Years 2025, 2035 and 2050**  **by Heavy******

**Duty Vehicle Category**  **– Preferred Alternative vs. Alt 1a using Analysis Method A**  **a** CY VEHICLE CATEGORY CO 2

(MMT) CH4

(MMT CO 2 EQ) N2 O

(MMT CO 2 EQ) A TO TAL

UPSTREAM (MMT CO 2 EQ) 2025 HD Pickups and Vans - 0.7 - 0.1 0 - 0.9 Vocational - 0.7 - 0.1 0 - 0.8 Tractor- Trailers - 7.1 - 0.7 0 - 7.9 Total - 8.6 - 0.9 - 0.1 - 9.6 2035 HD Pickups and Vans - 2.8 - 0.4 - 0.1 - 3.3 Vocational - 3.6 - 0.4 0 -4 .0 Tractor- Trailers - 22.6 - 2.3 - 0.1 - 25 .0 Total - 29 .0 - 3.1 - 0.2 - 32.3 2050 HD Pickups and Vans - 3.5 - 0.5 - 0.1 -4.1 Vocational - 5.1 - 0.6 0 - 5.7 Tractor- Trailers - 32.8 - 3.3 - 0.2 - 36.3 Total -41.4 -4.4 - 0.3 -46.1 Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1

### *** E.O. 12866 Review **– REVISED**  **– Do Not Cite, Quote, or Release During Review ** ***

5 - 38 **Table 5**  **- 45**  **Annual Upstream GHG Emissions Impacts in Calendar Years 2025, 2035 and 2050**  **by Heavy******

**Duty Vehicle Category**  **– Alternative 4 vs. Alt 1b using Analysis Method A**  **a** CY VEHICLE CATEGORY CO 2

(MMT) CH4

(MMT CO 2 EQ) N2 O

(MMT CO 2 EQ) A TO TAL

UPSTREAM (MMT CO 2 E Q) 2025 HD Pickups and Vans - 0.9 - 0.1 0 - 1 .0 Vocational - 1.2 - 0.1 0 - 1.3 Tractor- Trailers - 8.2 - 0.8 0 - 9.1 Total - 10.3 - 1.1 - 0.1 - 11.5 2035 HD Pickups and Vans - 2.7 - 0.4 - 0.1 - 3.2 Vocational - 3.8 - 0.4 0 -4.3 Tractor- Trailers - 21.2 - 2.2 - 0.1 - 23.5 Total - 27.8 - 3 .0 - 0.2 - 31 .0 2050 HD Pickups and Vans - 3.3 - 0.5 - 0.1 -4 .0 Vocational - 5.1 - 0.6 0 - 5.7 Tractor- Trailers - 29.5 - 3 .0 - 0.1 - 32.7 Total - 38 .0 -4 .0 - 0.3 -42.3 Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1 **Table 5**  **- 46**  **Annual Upstream GHG Emissions Impacts in Calendar Years 2025, 2035 and 2050**  **by Heavy******

**Duty Vehicle Category**  **– Alternative 4 vs. Alt 1a using Analysis Method A**  **a** CY VEHICLE CATEGORY CO 2

(MMT) CH4

(MMT CO 2 EQ) N2 O

(MMT CO 2 EQ) A TO TAL

UPSTREAM (MMT CO 2 EQ) 2025 HD Pickups and Vans - 1 .0 - 0.2 0 - 1.2 Vocational - 1.2 - 0.1 0 - 1.3 Tractor- Trailers - 8.4 - 0.8 0 - 9.2 Total - 10.6 - 1.1 - 0.1 - 11.8 2035 HD Pickups and Vans - 3.1 - 0.4 - 0.1 - 3.6 Vocational - 3.8 - 0.4 0 -4.3 Tractor- Trailers - 23.3 - 2.4 - 0.1 - 25.8 Total - 30.2 - 3.2 - 0.2 - 33.7 2050 HD Pickups and Vans - 3.7 - 0.5 - 0.1 -4.4 Vocational - 5.1 - 0.6 0 - 5.7 Tractor- Trailers - 32.9 - 3.3 - 0.2 - 36.4 Total -41.7 -4.4 - 0.3 -46.5 Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1

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5 - 39 

### 5.4.1.1.1 HFC Impacts The projected HFC emission reductions due to the proposed AC leakage standards are estimated to be 93,272 metric tons of CO 2 

### eq in 2025, 253,118 metric tons of CO 2 

### eq in 2035, and 299,590 metric tons CO 2 

### eq in 2050. 

### 5.4.1.1.2 Total (Downstream + Upstream + HFC) Impacts **Table 5**  **- 47**  **Annual Total GHG Emissions Impacts in Calendar Years 2025, 2035 and 2050 –**  **Preferred Alternative vs. Alt 1b using Analysis Method A**  **a** CY 2025 (MMT CO 2 EQ) 2035 (MMT CO 2 EQ) 2050 (MMT CO 2 EQ) Downstream - 27.2 - 86.9 - 123 .0 Upstream - 9.3 - 29.7 -42 .0 HFC - 0.09 - 0.25 - 0.3 Total - 36. 6 - 116. 9 - 165.3 Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1 **Table 5**  **- 48**  **Annual Total GHG Emissions Impacts in Calendar Years 2025, 2035 and 2050 –**  **Preferred Alternative vs. Alt 1a using Analysis Method A**  **a** CY 2025 (MMT CO 2 EQ) 2035 (MMT CO 2 EQ) 2050 (MMT CO 2 EQ) Downstream - 28.1 - 94.6 - 134.9 Upstream - 9.6 - 32.3 -46.1 HFC - 0.09 - 0.25 - 0.3 Total - 37. 8 - 127. 2 - 181.3 Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1 **Table 5**  **- 49**  **Annual Total GHG Emissions Impacts in Calendar Years 2025, 2035 and 2050 –**  **Alternative 4 vs. Alt 1b using Analysis Method A**  **a** CY 2025 (MMT CO 2 EQ) 2035 (MMT CO 2 EQ) 2050 (MMT CO 2 EQ) Downstream - 33.5 - 90.9 - 124 .0 Upstream - 11.5 - 31 .0 -42.3 HFC - 0.09 - 0.25 - 0.3 Total -45. 1 - 122. 2 - 166.6 Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1

### *** E.O. 12866 Review **– REVISED**  **– Do Not Cite, Quote, or Release During Review ** ***

5 - 40 **Table 5**  **- 50**  **Annual Total GHG Emissions Impacts in Calendar Years 2025, 2035 and 2050 –**  **Alternative 4 vs. Alt 1a using Analysis Method A**  **a** CY 2025 (MMT CO 2 EQ) 2035 (MMT CO 2 EQ) 2050 (MMT CO 2 EQ) Downstream - 34.6 - 98.7 - 136 .0 Upstream - 11.8 - 33.7 -46.5 HFC - 0.09 - 0.25 - 0.3 Total -46. 5 - 132. 7 - 182.8 Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1 

### 5.4.1.1 **Model Year Lifetime Analysis Table**  **5 -**  **51 Lifetim** **e GHG Reductions and Fuel Savings**  **by Heavy -** **Duty Vehicle Category –**  **Summary for Model Years 2018**  **- 2029**  **using Analysis Metho d**  **A a** 

ALTERNATIVE 3 (PROPOSED) ALTERNATIVE 4 NO -ACT ION ALTERNATIVE (BASELINE) 1b (More Dynamic) 1a (Less

Dynamic) 1b (More

Dynamic) 1a (Less

Dynamic) Fuel Savings (Billion Gallons) 72.2 76.7 81. 9 86.7 HD Pickups and Vans 7.8 8. 9 9. 4 10. 8 Vocational 8.3 8.3 10.9 10.9 Tractor/Trailers 56.1 59.5 61.6 65.0 Total GHG Reductions (MMT CO 2 eq) 986.5 1,047.4 1,114.8 1,181.1 HD Pickups and Vans 94.8 108.5 113.7 132.8 Vocational 109.7 109.7 143.0 143.0 Tractor/Trailers 782.0 829.2 858.1 905.3 Note: a For an explanation of analytical Methods A and B, please see Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Section X.A.1. 

### 5.4.2 **Impacts of the Proposed Rules**  **and Alternative 4 using Analysis Method B**  **5.4.2.1 Calendar Year Analysis**  5.4.2.1.1 Downstream Impacts After all the MOVES runs and post-processing was completed, the less dy namic reference (Alternative 1a) and control case (Alternative 3) inventories were totaled for all heavyduty vehicle ty

pes and emission processes to estimate total downstream GHG and fuel consumption impacts of the program . To estimate the fuel savings from the proposed rule s , the total energy consumption for all HD segments was run as a surrogate in MOVES since fuel consumption is not directly modeled in MOVES. Then, the total energy consumption was converted to fuel consumption based on

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5 - 41 fuel heating values assumed in the Renewable Fuels Standard rulemaking M 

### and used in the development of MOVES emis sion and energy rates. N 

### Table 5 - 52 and Table 5 - 53 summarize these downstream GHG impacts in calendar ye ars 2025, 2035, and 2050, relative to Alternative 1a, for the preferred alternative and Alternative 4, respectivel y. Table 5 - 54 and Table 5 - 55 show the estimated fuel savings from the preferred alternative and Alternative 4 in 2025, 2035, and 2050, relative to Alternative 1a. The reductions in CO 2 

### emissions result from all heavy- duty vehicle categories (including the engines associated with tractor- trailer combinations and vocational vehicles) due to engine and vehicle improvements. N2 

### O emissions show a very slight increase because of a rebound in vehicle miles traveled (VMT). However, since N2 

### O is produced as a by product of fuel combustion, the increase in N2 

### O emissions is expected to be more than offset b y the improvements in fuel efficiency from the proposed rules. O 

### The methane emissions decrease primarily due to differences in hydrocarbon emi ssion characteristics between on -road diesel engines and APUs. The amount of methane emitted as a fraction of total hydrocarbons is expected to be significantl y less for APUs than for diesel engines. Overall, downstream GHG emissions would be reduced significantl y. In addition, substantial fuel savings would be achieved from improved fuel efficiency . All emissions impacts reflect the heavy- duty sector onl y, and do not include emissions from light- duty vehicles or any

other vehicle sector.

M Renewable Fuels Standards assumptions of 115,000 BTU/gallon gasoline (E0) and 76,330 BTU/gallon ethanol (E100) were weighted 90% and 10%, respectively, for E10 and 85% and 15%, respectively, for E15 and converted to kJ at 1.055 kJ/B TU. The conversion factors are 117,245 kJ/gallon for gasoline blended with ten percent ethanol (E10) and 115,205 kJ/gallon for gasoline blended with fifteen percent ethanol (E15). N The conversion factor for diesel is 138,451 kJ/gallon. See MOVES2004 Energy and Emission Inputs. EPA420 - P 05 - 003, March 2005. http://www.epa.gov/otaq/models/ngm/420p05003.pdf O MOVES is not capable of modeling the changes in exhaust N 2 O emissions from the improvements in fuel efficiency. Due to this limitation, a conservative approach was taken to only model the VMT rebounds in estimating the emissions impact on N 2 O from the proposed rules, resulting in a slight increase in downstream N 2 O inventory.

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5 - 42 **Table 5**  **- 52**  **Annual Downstream GHG Emissions Impacts in Calendar Years 2025, 2035 and 2050 by Heavy** ****

**Duty Vehicle Category –**  **Preferred Alternative vs. Alt 1a using Analysis Method B** a CY VEHICLE CATEGORY CO 2

(MMT) CH4

(MMT CO 2 EQ) N2 O

(MMT CO 2 EQ) TO TAL

DOWNSTREAM (MMT CO 2 EQ) 2025 HD Pickups and Vans - 2.1 0.0003 0.0005 - 2.1 Vocational - 2.4 0.0009 0.0007 - 2.4 Tractor- Trailers - 22.5 - 0.4 0.0006 - 22.9 Total - 27.0 - 0.4 0.002 - 27.4 2035 HD Pickups and Vans - 10.6 0.0007 0.001 - 10.6 Vocational - 11.9 0.002 0.002 - 11.9 Tractor- Trailers - 71. 2 - 1.0 0.001 - 72. 2 Total - 93. 7 - 1.0 0.004 - 94. 7 2050 HD Pickups and Vans - 14.8 0.0009 0.001 - 14.8 Vocational - 17.2 0.003 0.002 - 17.2 Tractor- Trailers - 103. 1 - 1.4 0.00 2 - 104. 5 Total - 135. 1 - 1.4 0.00 5 - 136. 5 Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1 **Table 5**  **- 53**  **Annual Downstream GHG Emissions Impacts in Calendar Years 2025, 2035 and 2050 by Heavy** ****

**Duty Vehicle Category –** **Alternative 4 vs. Alt 1a using Analysis Method B** a CY VEHICLE CATEGORY CO 2

(MMT) CH4

(MMT CO 2 EQ) N2 O

(MMT CO 2 EQ) TO TAL

DOWNSTREAM (MMT CO 2 EQ) 2025 HD Pickups and Vans - 3.1 0.0003 0.0005 - 3.1 Vocational -4.0 0.0009 0.0007 -4.0 Tractor- Trailers - 26.2 - 0.4 0.0006 - 26.6 Total - 33.3 - 0.4 0.002 - 33.7 2035 HD Pickups and Vans - 11.2 0.0007 0.001 - 11.2 Vocational - 12.9 0.0024 0.002 - 12.9 Tractor- Trailers - 73.2 - 1.0 0.001 - 74.2 Total - 97.3 - 1.0 0.004 - 98.3 2050 HD Pickups and Vans - 14.9 0.0009 0.001 - 14.9 Vocational - 17.3 0.003 0.002 - 17.3 Tractor- Trailers - 103.3 - 1.4 0.002 - 104.7 Total - 135.5 - 1.4 0.005 - 136.9 Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1

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5 - 43 **Table 5**  **- 54**  **Annual Fuel Savings in Calendar Years 2025, 2035 and 2050 by Heavy -** **Duty Vehicle Category**  **– Preferred Alternative vs. Alt 1a**  **using Analysis Method B a**  CY VEHICLE CATEGORY DIESEL SAVINGS (BILLION GALLONS) GASOLINE SAVINGS (BILLION GALLONS) 2025 HD Pickups and Vans 0.1 0.1 Vocational 0.2 0.0 5 Tractor- Trailers 2.2 0 Total 2.5 0. 2 2035 HD Pickups and Vans 0. 5 0.6 Vocational 1.0 0.2 Tractor- Trailers 7.0 0 Total 8. 5 0.8 2050 HD Pickups and Vans 0.8 0.8 Vocational 1.4 0.3 Tractor- Trailers 10.1 0 Total 12.3 1.1 Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1 **Table 5**  **- 55**  **Annual Fuel Savings in Calendar Years 2025, 2035 and 2050 by Heavy -** **Duty Vehicle Category**  **– Alternative 4 vs. Alt 1a using Analysis Method B**  **a** CY VEHICLE CATEGORY DIESEL SAVINGS (BILLION GALLONS) GASOLINE SAVINGS (BILLION GALLONS) 2025 HD Pickups and Vans 0.2 0.2 Vocational 0.3 0.1 Tractor- Trailers 2.6 0 Total 3.1 0.3 2035 HD Pickups and Vans 0.6 0.6 Vocational 1.0 0.3 Tractor- Trailers 7.2 0 Total 8.8 0.9 2050 HD Pickups and Vans 0.8 0.8 Vocational 1.4 0.3 Tractor- Trailers 10.1 0 Total 12.3 1.1 Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1 

### 5.4.2.1.2 Upstream Impacts The upstream GHG impacts of preferre d alternative and Alternative 4 associated with the production and distribution of gasoline and diesel from crude oil , relative to Alternative 1a, are summarized in Table 5 - 56 and Table 5 - 57 , for calendar years 2025, 2035, and 2050 . These estimates show impacts for domestic emission reductions only . Additionally, since this

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5 - 44 rulemaking is not expected to impact biofuel volumes mandated b y the Annual Renewable Fuel Standards (RFS) regulations, the impacts on upstream emissions from changes in biofuel feedstock (i.e., agricultural sources such as fertilizer, fugitive dust, and livestock) are not included. The reductions in upstream GHGs are proportional to the amount of fuel saved. **Table 5**  **- 56**  **Annual Upstream GHG Emissions Impacts in Calendar Years 2025, 2035 and 2050**  **by Heavy******

**Duty Vehicle Category**  **– Preferred Alternative vs. Alt 1a**  **using Analysis Method B a**  CY VEHICLE CATEGORY CO 2

(MMT) CH4

(MMT CO 2 EQ) N2 O

(MMT CO 2 EQ) TO TAL

UPSTREAM (MMT CO 2 EQ) 2025 HD Pickups and Vans - 0.6 - 0.1 - 0.003 - 0.7 Vocational - 0.7 - 0.1 - 0.004 - 0.8 Tractor- Trailers - 7.1 - 0.7 - 0.03 - 7.8 Total - 8.4 - 0.9 - 0.04 - 9.3 2035 HD Pickups and Vans - 2.9 - 0.3 - 0.02 - 3.2 Vocational - 3.6 - 0.4 - 0.02 -4.0 Tractor- Trailers - 22.6 - 2.3 - 0.1 - 25.0 Total - 29.1 - 3.0 - 0.1 - 32.2 2050 HD Pickups and Vans -4.0 - 0.5 - 0.02 -4.5 Vocational - 5.1 - 0.6 - 0.03 - 5.7 Tractor- Trailers - 32.8 - 3.3 - 0.2 - 36.3 Total -41.9 -4.4 - 0.2 -46.5 Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1

### *** E.O. 12866 Review **– REVISED**  **– Do Not Cite, Quote, or Release During Review ** ***

5 - 45 **Table 5**  **- 57**  **Annual Upstream GHG Emissions Impacts in Calendar Years 2025, 2035 and 2050 by Heavy** ****

**Duty Vehicle Category**  **– Alternative 4 vs. Alt 1a using Analysis Method B**  **a** CY VEHICLE CATEGORY CO 2

(MMT) CH4

(MMT CO 2 EQ) N2 O

(MMT CO 2 EQ) TO TAL

UPSTREAM (MMT CO 2 E Q) 2025 HD Pickups and Vans - 0.8 - 0.1 - 0.005 - 1.0 Vocational - 1.2 - 0.1 - 0.01 - 1.3 Tractor- Trailers - 8.4 - 0.8 - 0.04 - 9.2 Total - 10.4 - 1.0 - 0.1 - 11.5 2035 HD Pickups and Vans - 3.0 - 0.4 - 0.02 - 3.4 Vocational - 3.8 - 0.4 - 0.02 -4.2 Tractor- Trailers - 23.3 - 2.4 - 0.1 - 25.8 Total - 30.1 - 3.2 - 0.1 - 33.4 2050 HD Pickups and Vans -4.0 - 0.5 - 0.02 -4.5 Vocational - 5.1 - 0.6 - 0.03 - 5.7 Tractor- Trailers - 32.9 - 3.3 - 0.2 - 36.4 Total -42.0 -4.4 - 0.2 -46.6 Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1 

### 5.4.2.1.3 HFC Impacts Based on projected HFC emission reductions due to the proposed AC leakage standards, EPA estimates the HFC reductions to be 93, 272 metric tons of CO 2 

### eq in 2025, 253,118 metric tons of CO 2 

### eq in 2035, and 299,590 metric tons CO 2 

### eq in 2050 . 

### 5.4.2.1.4 Total (Downstrea m + Upstream + HFC) Impacts The combine d annual GHG emissions reductions of preferred alternative from downstream, upstream, and HFC , relative to Alternative 1a, are summarized in T able 5 - 58 for calendar years 2025, 2035 and 2050 . The combined impact of Alternative 4 on total GHG emissions are shown in Table 5 - 59 . Because of the differences in lead time, as expected, Alternative 4 shows greater annual GHG reductions in earlier ye ars (i.e., calendar ye ar 2025), but by 2050, the preferred alternative and Alternative 4 show the same magnitude of reductions in annual GHG emissions.

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5 - 46 **T able**  **5 -**  **58 Annual Total GHG Emissions**  **Im pacts**  **in Calendar Years 2025, 2035 and 2050 –**  **Preferred Alternative vs. Alt 1a**  **using Analysis Method B a**  CY 2025 (MMT CO 2 EQ) 2035 (MMT CO 2 EQ) 2050 (MMT CO 2 EQ) Downstream - 27.4 - 94.7 - 136.5 Upstream - 9.3 - 32.2 -46.5 HFC - 0.1 - 0.25 - 0.3 Total - 36.8 - 127.2 - 183.3 Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1 **Table 5**  **- 59**  **Annual Total GHG Emissions Impacts in Calendar Years 2025, 2035 and 2050 –**  **Alternative 4 vs. Alt 1a using Analysis Method B**  **a** CY 2025 (MMT CO 2 EQ) 2035 (MMT CO 2 EQ) 2050 (MMT CO 2 EQ) Downstream - 33.7 - 98. 3 - 136. 9 Upstream - 11.5 - 33. 4 -46.6 HFC - 0.1 - 0.25 - 0.3 Total -45.3 - 132.0 - 183. 8 Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1 

### Figure 5 - 3 graphically

illustrates the total annual GHG trends for both Phase 1 and Phase 2 proposal, using Method B, for calendar ye ars from 2014 to 2050. The less dy namic baseline from Phase 2 proposal is assumed to be equivalent to the Phase 1 program.

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5 - 47 **Figure 5**  **- 3**  **Total Annual GHG Trends for Phase 1 and Phase 2 Proposal, using Analysis Method B**  

### 5.4.2.2 **Model Year Lifetime Analysis**  In addition to the annual GHG emissions and fuel consumption reductions expected from the proposed rules and Alternative 4 , the combined (downstream and upstream) GHG and fuel consumption impacts over the model year lifetimes of the impacted vehicles sold in the regulatory

timeframe were estimated. In contrast to the calendar ye ar analysis, the model year lifetime anal ys e s show the impacts of the program on each of these model year fleets over the course of their lifetime s . Table 5 - 60 show s the fleet- wide GHG reductions and fuel savings from the proposed rules and Alternative 4 through the lifetime P 

### of heavy- duty vehicles , relative to Alternative 1a . In addition, because the agencies are carefully considering Alternative 4 along with the preferred alternative, the lifetime GHG reductions and fuel savings of Alternative 4 are presented as well in Table 5 - 60 . Compared to the preferred alternative, Alternative 4 shows greater lifetime GHG reductions and fuels savings by 12 percent and 13 percent, respectivel y.

P A lifetime of 30 years is assumed in MOVES.

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5 - 48 **Table 5**  **- 60**  **Lifetim e GHG Reductions**  **and Fuel Savings by Heavy -** **Duty Vehicle Category –**  **Summary for Model Years 2018**  **- 2029**  **using Analysis Method B**  **a** ALTERNATIVE 3 (PROPOSED) ALTERNATIVE 4 NO -ACT ION ALTERNATIVE (BASELINE) 1a (Less Dynamic) 1a (L ess Dynamic) Fuel Savings (Billion Gallons) 75.8 85.4 HD Pickups and Vans 8.0 9.5 Vocational 8.3 10.9 Tractor/Trailers 59.5 65.0 Total GHG Reductions (MMT CO 2 eq) 1,036.4 1,163.1 HD Pickups and Vans 97.5 114.8 Vocational 109.7 143.0 Tractor/Trailers 829.2 905.3 Note: a For an explanation of analytical Methods A and B, please see Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Section X.A.1. 

### Furthermore, the combined lifetime GHG reductions and fuel savings of Phase 1 and proposed Phase 2 programs are presented in Table 5 - 62 . To be consistent with the emi ssions modeling done for this proposed program, the lifetime GHG reductions and fuel savings from Phase 1 were estimated using the same modeling tools used in the proposed program. **Table 5**  **- 61**  **Combined Lifet** **im e GHG Reductions**  **and Fuel Savings of**  **Phase 1 and Proposed Phase 2**  **Program using Analysis Method**  **B a**  TO TAL GHG REDUCTIONS (MMT CO 2 EQ ) FUEL SAVINGS (BILLION GALLONS) Phase 1 MY 2014 - 2018 313 23 MY 2019 - 2029 1,020 75 Phase 2 - Proposed MY 2018 - 2029 1,036 76 Combined Total 2,369 174 Note: a For an explanation of analytical Methods A and B, please see Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Section X.A.1. 

## 5.5 **Non -**  **Greenhouse Gas Emission Impacts**  The proposed heavy- duty vehicle standards and Alternative 4 are expected to influence the emissions of criteria air pollutants and several air toxics. Similar to Section 5.4 , the following subsections summarize two slightly different analyses of the annual non - GHG emissions reductions exp ected from the proposed s tandards . Section 5.5.1 shows the impacts of the proposed rules and Alternative 4 on non - GHG emissions using the analytical Method A, relative to two different reference cases

– less dy namic and more dyn amic . Section 5.5.2 shows

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5 - 49 the impacts of the proposed standards and Alternative 4 , relative to the less dy namic reference case onl y, using the MOVES model for all heavy- duty vehicle categories. 

### 5.5.1 **Impacts of the Proposed Rules and Alternative 4 using Analysis Method A 5.5.1.1**  **Calendar Year Analysis** 5.5.1.1.1 Downstream Impacts **Table 5**  **- 62**  **Annual Downstream Im** **pacts of Heavy -** **Duty Non -**  **G HG Emissions in Calendar Years 2025, 2035** 

**and 2050**  **– Preferred Alternative vs. Alt 1b using Analysis Method A**  **a** POLLUTANT CY2025 CY2035 CY2050

US Short Tons % Reduction US Short Tons % Reduction US Short Tons % Reduction 1,3 -Butadiene - 8 - 3 % - 21 - 12 % - 30 - 16 % Acetaldehyde - 669 - 10 % - 1,882 - 31 % - 2,667 - 36 % Acrolein - 97 - 10 % - 272 - 31 % - 385 - 37 % Benzene - 123 - 6 % - 347 - 19 % -490 - 24 % CO - 26,485 - 3 % - 75,199 - 8 % - 106,756 - 9 % Formaldehyde - 2,100 - 12 % - 5,910 - 32 % - 8,376 - 37 % NO X - 92,444 - 7 % - 260,949 - 28 % - 370,663 - 34 % PM 2.5 643 2 % 1,722 8 % 2,410 10 % SO X - 229 -4 % - 715 - 13 % - 1,026 - 15 % VOC - 13,161 - 6 % - 38,051 - 21 % - 54,139 - 26 % Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1 **Table 5**  **- 63**  **Annual Downstream Im** **pacts of Heavy -** **Duty Non -**  **GHG Emissions in Calendar Years 2025, 2035**

**and 2050**  **– Preferred Alternative vs. Alt 1a using Analysis Method A**  **a** POLLUTANT CY2025 CY2035 CY2050

US Short Tons % Reduction US Short Tons % Reduction US Short Tons % Reduction 1,3 -Butadiene - 8 - 3 % - 21 - 12 % - 30 - 16 % Acetaldehyde - 669 - 10 % - 1,880 - 31 % - 2,664 - 36 % Acrolein - 97 - 10 % - 271 - 31 % - 384 - 37 % Benzene - 123 - 6 % - 346 - 19 % -490 - 24 % CO - 26,576 - 3 % - 75,571 - 8 % - 107,287 - 9 % Formaldehyde - 2,100 - 12 % - 5,904 - 32 % - 8,369 - 37 % NO X - 93,197 - 8 % - 266,890 - 29 % - 380,303 - 35 % PM 2.5 632 2 % 1,635 8 % 2,267 9 % SO X - 232 -4 % - 776 - 14 % - 1,125 - 16 % VOC - 13,210 - 6 % - 38,964 - 22 % - 55,628 - 26 % Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1

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5 - 50 **Table 5**  **- 64**  **Annual Downstream Im** **pacts of Heavy -** **Duty Non -**  **GHG Emissions in Calendar Years 2025, 2035**

**and 2050**  **– Alternative 4 vs. Alt 1b using Analysis Method A**  **a** POLLUTANT CY2025 CY2035 CY2050

US Short Tons % Reduction US Short Tons % Reduction US Short Tons % Reduction 1,3 -Butadiene - 8 - 2 % - 21 - 12 % - 30 - 16 % Acetaldehyde - 669 - 10 % - 1,882 - 31 % - 2,667 - 36 % Acrolein - 97 - 10 % - 271 - 31 % - 385 - 37 % Benzene - 124 - 6 % - 347 - 19 % -490 - 24 % CO - 26,705 - 3 % - 75,407 - 8 % - 106,874 - 9 % Formaldehyde - 2,100 - 12 % - 5,908 - 32 % - 8,375 - 37 % NO X - 93,984 - 8 % - 262,150 - 28 % - 370,704 - 34 % PM 2.5 619 2 % 1,705 8 % 2,412 10 % SO X - 280 - 5 % - 742 - 13 % - 1,029 - 15 % VOC - 13,925 - 7 % - 38,472 - 22 % - 54,150 - 26 % Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1 **Table 5**  **- 65**  **Annual Downstream Im** **pacts of Heavy -** **Duty Non -**  **GHG Emissions in Calendar Years 2025, 2035 and**  **2050 –**  **Alternative 4 vs. Alt 1a using Analysis Method A a**  POLLUTANT CY2025 CY2035 CY2050

US Short Tons % Reduction US Short Tons % Reduction US Short Tons % Reduction 1,3 -Butadiene - 8 - 2 % - 21 - 12 % - 29 - 16 % Acetaldehyde - 668 - 10 % - 1,880 - 31 % - 2,664 - 36 % Acrolein - 97 - 10 % - 271 - 31 % - 384 - 37 % Benzene - 124 - 6 % - 346 - 19 % -489 - 24 % CO - 26,821 - 3 % - 75,795 - 8 % - 107,414 - 9 % Formaldehyde - 2,099 - 12 % - 5,902 - 32 % - 8,367 - 37 % NO X - 94,724 - 8 % - 268,075 - 29 % - 380,328 - 35 % PM 2.5 609 2 % 1,618 8 % 2,269 9 % SO X - 282 - 5 % - 803 - 14 % - 1,127 - 16 % VOC - 13,971 - 7 % - 39,383 - 22 % - 55,638 - 26 % Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1 

### 5.5.1.1.2 Upstream Impacts

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5 - 51 **Table 5**  **- 66**  **Annual Upstream Impacts of Heavy -** **Duty Non -**  **GHG Emissions in Calendar Years 2025, 2035 and**

**2050 –**  **Preferred Alternative vs. Alt 1b using Analysis Method A a**  POLLUTANT CY2025 CY2035 CY2050

US Short Tons % Reduction US Short Tons % Reduction US Short Tons % Reduction 1,3 -Butadiene - 1 - 5 % - 3 - 14 % - 5 - 17 % Acetaldehyde - 3 - 3 % - 10 - 11 % - 15 - 13 % Acrolein 0 -4 % - 1 - 12 % - 2 - 15 % Benzene - 21 -4 % - 74 - 13 % - 104 - 15 % CO - 3,798 - 5 % - 12,087 - 14 % - 17,120 - 17 % Formaldehyde - 19 - 5 % - 59 - 14 % - 84 - 17 % NO X - 9,472 - 5 % - 30,333 - 14 % -42,839 - 17 % PM 2.5 - 1,019 - 5 % - 3,257 - 14 % -4,609 - 17 % SO X - 5,983 - 5 % - 19,190 - 14 % - 27,074 - 17 % VOC - 3,066 -4 % - 11,029 - 13 % - 15,386 - 15 % Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1

**Table 5**  **- 67**  **Annual Upstream Impacts of Heavy -** **Duty Non -**  **GHG Emissions in Calendar Years 2025, 2035 and**

**2050 –**  **Preferred Alternative vs. Alt 1a using Analysis Method A a**  POLLUTANT CY2025 CY2035 CY2050

US Short Tons % Reduction US Short Tons % Reduction US Short Tons % Reduction 1,3 -Butadiene - 1 - 5 % -4 - 15 % - 5 - 18 % Acetaldehyde - 3 - 3 % - 11 - 12 % - 16 - 14 % Acrolein 0 -4 % - 1 - 13 % - 2 - 15 % Benzene - 22 -4 % - 80 - 14 % - 113 - 16 % CO - 3,911 - 5 % - 13,153 - 15 % - 18,794 - 18 % Formaldehyde - 19 - 5 % - 65 - 15 % - 92 - 18 % NO X - 9,787 - 5 % - 33,021 - 15 % -47,028 - 18 % PM 2.5 - 1,051 - 5 % - 3,545 - 15 % - 5,058 - 18 % SO X - 6,189 - 5 % - 20,896 - 15 % - 29,726 - 18 % VOC - 3,193 -4 % - 11,848 - 13 % - 16,625 - 16 % Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1

### *** E.O. 12866 Review **– REVISED**  **– Do Not Cite, Quote, or Release During Review ** ***

5 - 52 **Table 5**  **- 68**  **Annual Upstream Impacts of Heavy -** **Duty Non -**  **GHG Emissions in Calendar Years 2025, 2035 and 2050**  **– Alternative 4 vs. Alt 1b using Analysis Method A**  **a** POLLUTANT CY2025 CY2035 CY2050

US Short Tons % Reduction US Short Tons % Reduction US Short Tons % Reduction 1,3 -Butadiene - 1 - 6 % - 3 - 15 % - 5 - 17 % Acetaldehyde -4 - 5 % - 11 - 12 % - 15 - 14 % Acrolein - 1 - 5 % - 1 - 13 % - 2 - 15 % Benzene - 28 - 5 % - 78 - 13 % - 105 - 16 % CO -4,679 - 6 % - 12,640 - 15 % - 17,263 - 17 % Formaldehyde - 23 - 6 % - 62 - 15 % - 85 - 17 % NO X - 11,708 - 6 % - 31,769 - 15 % -43,263 - 17 % PM 2.5 - 1,259 - 6 % - 3,408 - 15 % -4,649 - 17 % SO X - 7,402 - 6 % - 20,107 - 15 % - 27,356 - 17 % VOC -4,081 - 5 % - 11,717 - 13 % - 15,645 - 15 % Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1

**Table 5**  **- 69**  **Annual Upstream Impacts of Heavy -** **Duty Non -**  **GHG Emissions in Calendar Years 2025, 2035 and 2050**  **– Alternative 4 vs. Alt 1a using Analysis Method A**  **a** POLLUTANT CY2025 CY2035 CY2050

US Short Tons % Reduction US Short Tons % Reduction US Short Tons % Reduction 1,3 -Butadiene - 1 - 6 % -4 - 16 % - 5 - 18 % Acetaldehyde -4 - 5 % - 12 - 12 % - 16 - 14 % Acrolein - 1 - 5 % - 1 - 13 % - 2 - 16 % Benzene - 29 - 5 % - 84 - 14 % - 114 - 17 % CO -4,816 - 6 % - 13,720 - 16 % - 18,945 - 18 % Formaldehyde - 24 - 6 % - 67 - 16 % - 93 - 18 % NO X - 12,098 - 6 % - 34,501 - 16 % -47,477 - 18 % PM 2.5 - 1,298 - 6 % - 3,700 - 16 % - 5,101 - 18 % SO X - 7,658 - 6 % - 21,843 - 16 % - 30,024 - 18 % VOC -4,251 - 5 % - 12,541 - 14 % - 16,870 - 16 % Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1 

### 5.5.1.1.3 Total Impacts

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5 - 53 **Table 5**  **- 70**  **Annual Total Impacts (Upstream and Downstream** **) of Heavy -** **Duty Non -**  **GHG Emissions in Calendar Years 2025, 2035 and**  **2050 –**  **Preferred Alternative vs. Alt 1b using Analysis Method A a**  POLLUTANT CY2025 CY2035 CY2050

US Short Tons % Reduction US Short Tons % Reduction US Short Tons % Reduction 1,3 -Butadiene - 9 - 3 % - 25 - 13 % - 34 - 16 % Acetaldehyde - 672 - 10 % - 1,893 - 30 % - 2,682 - 36 % Acrolein - 97 - 10 % - 273 - 31 % - 387 - 37 % Benzene - 145 - 5 % -421 - 18 % - 595 - 22 % CO - 30,282 - 3 % - 87,286 - 8 % - 123,876 - 10 % Formaldehyde - 2,119 - 11 % - 5,969 - 32 % - 8,460 - 37 % NO X - 101,916 - 7 % - 291,282 - 26 % -413,501 - 31 % PM 2.5 - 376 - 1 % - 1,535 - 3 % - 2,199 -4 % SO X - 6,213 - 5 % - 19,905 - 14 % - 28,101 - 17 % VOC - 16,227 - 6 % -49,080 - 18 % - 69,525 - 22 % Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1 **Table 5**  **- 71**  **Annual Total Impacts (Upstream and Downstream** **) of Heavy -** **Duty Non -**  **GHG Emissions in Calendar Years 2025, 2035 and**  **2050 –**  **Preferred Alternative vs. Alt 1a using Analysis Method A a**  POLLUTANT CY2025 CY2035 CY2050

US Short Tons % Reduction US Short Tons % Reduction US Short Tons % Reduction 1,3 -Butadiene - 9 - 3 % - 25 - 13 % - 35 - 16 % Acetaldehyde - 672 - 10 % - 1,891 - 30 % - 2,680 - 36 % Acrolein - 97 - 10 % - 273 - 31 % - 386 - 37 % Benzene - 145 - 5 % -425 - 18 % - 603 - 22 % CO - 30,487 - 3 % - 88,724 - 8 % - 126,081 - 10 % Formaldehyde - 2,119 - 11 % - 5,969 - 32 % - 8,461 - 37 % NO X - 102,983 - 7 % - 299,911 - 26 % -427,332 - 32 % PM 2.5 -419 - 1 % - 1,910 -4 % - 2,791 - 5 % SO X - 6,421 - 5 % - 21,672 - 15 % - 30,850 - 18 % VOC - 16,403 - 6 % - 50,812 - 19 % - 72,253 - 23 % Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1

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5 - 54 **Table 5**  **- 72**  **Annual Total Impacts (Upstream and Downstream** **) of Heavy -** **Duty Non -**  **GHG Emissions in Calendar Years 2025, 2035 and**  **2050 –**  **Alternative 4 vs. Alt 1b using Analysis Method A a**  POLLUTANT CY2025 CY2035 CY2050

US Short Tons % Reduction US Short Tons % Reduction US Short Tons % Reduction 1,3 -Butadiene - 9 - 3 % - 25 - 13 % - 34 - 16 % Acetaldehyde - 673 - 10 % - 1,893 - 30 % - 2,682 - 36 % Acrolein - 97 - 10 % - 273 - 31 % - 387 - 37 % Benzene - 152 - 6 % -426 - 18 % - 595 - 22 % CO - 31,383 - 3 % - 88,047 - 8 % - 124,137 - 10 % Formaldehyde - 2,123 - 11 % - 5,970 - 32 % - 8,460 - 37 % NO X - 105,693 - 7 % - 293,918 - 26 % -413,967 - 31 % PM 2.5 - 639 - 1 % - 1,703 -4 % - 2,237 -4 % SO X - 7,682 - 6 % - 20,849 - 15 % - 28,385 - 17 % VOC - 18,006 - 6 % - 50,189 - 19 % - 69,796 - 22 % Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1 **Table 5**  **- 73**  **Annual Total Impacts (Upstream and Downstream** **) of Heavy -** **Duty Non -**  **GHG Emissions in Calendar Years 2025, 2035 and**  **2050 –**  **Alternative 4 vs. Alt 1a using Analysis Method A a**  POLLUTANT CY2025 CY2035 CY2050

US Short Tons % Reduction US Short Tons % Reduction US Short Tons % Reduction 1,3 -Butadiene - 9 - 3 % - 25 - 13 % - 35 - 16 % Acetaldehyde - 672 - 10 % - 1,891 - 30 % - 2,679 - 36 % Acrolein - 97 - 10 % - 273 - 31 % - 386 - 37 % Benzene - 153 - 6 % -430 - 18 % - 603 - 22 % CO - 31,637 - 3 % - 89,514 - 8 % - 126,360 - 10 % Formaldehyde - 2,123 - 11 % - 5,969 - 32 % - 8,460 - 37 % NO X - 106,822 - 7 % - 302,575 - 26 % -427,805 - 32 % PM 2.5 - 689 - 1 % - 2,082 - 5 % - 2,833 - 5 % SO X - 7,941 - 6 % - 22,646 - 16 % - 31,151 - 18 % VOC - 18,222 - 6 % - 51,924 - 19 % - 72,509 - 23 % Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1

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5 - 55 

### 5.5.1.2 **Model Year Lifetime Analysis Table**  **5 -**  **74 Lifetim** **e Non**  **- GHG Reductions**  **by Heavy -** **Duty Vehicle Category –**  **Summary for Model Years 2018**  **- 2029**  **using Analysis Method A**  **(US Short Tons) a** 

ALTERNATIVE 3 (PROPOSED) ALTERNATIVE 4 NO -ACT ION ALTERNATIVE (BASELINE) 1b (More Dynamic) 1a (Less

Dynamic) 1b (More

Dynamic) 1a (Less

Dynamic) NO X 2,359,54 8 2,409,73 8 2,420,93 1 2,472,021 HD Pickups and Vans 24,663 27,772 30,213 34,222 Vocational 15,810 15,810 24,265 24,265 Tractor/Trailers 2,319,075 2,366,156 2,366,453 2,413,534 PM 2.5 13,496 15,70 6 17,52 4 19,839 HD Pickups and Vans 2,502 2,842 3,038 3,484 Vocational 2,509 2,509 3,421 3,421 Tractor/Trailers 8,485 10,355 11,065 12,934 SO X 167,415 177,948 189,670 200,992 HD Pickups and Vans 19,221 21,813 23,395 26,776 Vocational 17,295 17,295 22,416 22,416 Tractor/Trailers 130,899 138,840 143,859 151,800 Note: a For an explanation of analytical Methods A and B, please see Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Section X.A.1. 

### 5.5.2 **Impacts of the Proposed Rules**  **and Alternative 4 using Analysis Method B**  **5.5.2.1 Calendar Year Analysis**  5.5.2.1.1 Downstream Impacts After all the MOVES runs Q 

### and post-processing were completed, the less dynamic reference (Alternative 1a) and control case (Alternative 3) inventories were aggregated for all vehicle types and emission processes to estimate the total downstream non - GHG impacts of the proposed program . Table 5 - 75 and Table 5 - 76 summarize these downstream non - GHG impacts of preferred alternative and Alternative 4 for calendar years 2025, 2035 and 2050 , relative to Alternative 1a . The results are shown both in changes in absolute tons and in percent reductions from the less dynamic reference to alternatives for the heavy- duty sector. The agencies expect the proposed program to impact the downstream emissions of non GHG pollutants . These pollutants include oxides of nitrogen (NO X

### ) , oxides of sulfur ( SO X

### ), Q For non- GHGs, MOVES was run only for January and July and the annual emissions were extrapolated by scaling up each month by a factor of 5.88 for all pollutants except particulate matter (PM). For PM, to offset the disproportionate effect of the cold tem perature on January results, a scaling factor of 4.3 was applied to January and 7.5 to July; these factors were determined based on analysis of annual PM emissions during modeling for the RFS2 rule. Note that for GHGs, MOVES was run for all months.

### *** E.O. 12866 Review **– REVISED**  **– Do Not Cite, Quote, or Release During Review ** ***

5 - 56 volatile organic compounds (VOC ) , carbon monoxide ( CO ) , fine particulate matter (PM 2.5 

### ) , and air toxics . The agencies are expecting reductions in downstream emissions of NO X, 

### VO C, SO X 

### , CO , and air toxics . Much of the se estimated net reductions are a result of the agenc ies ’ anticipation of increased use of auxiliary power units (APUs ) in combination tractors during extended idling ; APUs emit these pollutants at a lower rate than on - road engines d uring extended idle operation , with the exception of PM 2.5 

### . Additional reductions in tailpipe emissions of NO X 

### and CO and refueling emissions of VOC would be achieved through improvements in engine efficiency and reduced road load (improved aerodynamics and tire rolling resistance), which reduces the amount of work required to travel a given distance and increases fuel economy . For vehicle ty

pes not affected by

road load improvements , such as HD pickups and vans R 

### , non - GHG emissions would increase very slightl y due to VMT rebound . Inaddition, brake wear and tire wear emissions of PM 2.5 

### would also increase very slightly due to VMT rebound. The agencies estimate that downstream emissions of SO X 

### would be reduced, because they are roughly

proportional to fuel consumption. Alternative 4 would have directionall y similar effects as the preferred alternative. **Table 5**  **- 75**  **Annual Downstream Im** **pacts of Heavy** **- Duty Non**  **- GHG Emissions**  **in Calendar Y**  **ears 2025,**  **2035**

**and 2050 –**  **Preferred Alternative vs. Alt 1a using Analysis Method B a**  POLLUTANT CY2025 CY2035 CY2050

US Short Tons % Reduction US Short Tons % Reduction US Short Tons % Reduction 1,3 -Butadiene - 8 - 2.6 % - 22 - 15.1 % - 31 - 19.6 % Acetaldehyde - 670 - 10.3 % - 1,884 - 31.0 % - 2,671 - 36.5 % Acrolein - 97 - 9.9 % - 272 - 31.6 % - 385 - 37.3 % Benzene - 125 - 5.9 % - 353 - 21.0 % - 501 - 25.7 % CO - 25,824 - 1.7 % - 72,960 - 6.0 % - 103,887 - 7.6 % Formaldehyde - 2,102 - 11.5 % - 5,911 - 32.1 % - 8,379 - 37.5 % NO X - 93,220 - 7.5 % - 267,125 - 29.1 % - 380,721 - 35.2 % PM 2.5 634 1.6 % 1,631 7.6 % 2,257 9.1 % SO X - 254 -4.8 % - 876 - 15.0 % - 1,264 - 18.1 % VOC - 13,440 - 6.4 % -40,148 - 21.7 % - 57,308 - 26.1 % Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1

R HD p ickups and vans are subject to gram per mile (distance) emissions standards, as opposed to larger heavy- duty vehicles which are certified to a gram per brake horsepower (work) standard.

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5 - 57 **Table 5**  **- 76**  **Annual Downstream Im** **pacts of Heavy -** **Duty Non -**  **GHG Emissions in Calendar Years 2025, 2035 and 2050**  **– Alternative 4 vs. Alt 1a using Analysis Method B**  **a** POLLUTANT CY2025 CY2035 CY2050

US Short Tons % Reduction US Short Tons % Reduction US Short Tons % Reduction 1,3 -Butadiene - 8 - 2.6% - 22 - 15.1% - 31 - 19.6% Acetaldehyde - 670 - 10.3% - 1,884 - 31.0% - 2,671 - 36.5% Acrolein - 97 - 9.9% - 272 - 31.6% - 385 - 37.3% Benzene - 126 - 5.9% - 354 - 21.0% - 501 - 25.7% CO - 25,919 - 1.7% - 73,041 - 6.0% - 103,891 - 7.6% Formaldehyde - 2,101 - 11.5% - 5,910 - 32.1% - 8,378 - 37.5% NO X - 94,787 - 7.6% - 268,373 - 29.2% - 380,810 - 35.2% PM 2.5 610 1.5% 1,611 7.5% 2,256 9.1% SO X - 313 - 5.9% - 909 - 15.6% - 1,267 - 18.1% VOC - 14,310 - 6.8% -40,640 - 22.0% - 57,348 - 26.1% Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1 

### As shown in Table 5 - 77 , a net increase in downstream PM 2.5 

### emissions is expected in both 2035 and 2050. Although the improvements in engine efficiency and road load are expected to reduce tailpipe emissions of PM 2.5 

### , the projected increased use ( Table 5 - 23 ) of APUs would lead to higher PM 2.5 

### emissions that more than offset the reductions from the tailpipe, since engines powering AP Us are currentl y required to meet less stringent PM standards than on -road engines . Therefore, EPA conducted an evaluation of a program that would reduce the unintended consequence of increase in PM 2.5 

### emissions from increased APU use b y fitting the APU with a diesel particulate filter or having the APU exhaust plumbed into the vehicle’s exhaust system upstream of the particulate matter aftertreatment device. Such program requiring additional PM 2.5 

### controls on APU could significantly reduce PM 2.5 

### emission s, as shown in Table 5 - 77 below. For additional details, see Section III. C. 3 of the preamble. **Table 5**  **- 77**  **Projected Im** **pact on PM 2.5**  **Em issions of Further PM**  **2.5 Control on APUs**  **using Analysis Method B**  **a** CY PROPOSED

PROGRAM INVENTORY WITHOUT FURTHER PM 2.5 CONTROL ON APUS PROPOSED

PROGRAM INVENTORY WITH FURTHER PM 2.5 CONTROL ON APUS NET IMPACT OF

FURTHER PM 2.5 CONTROL ON APU S 2035 23,083 19,999 - 3,0 84 2050 26,932 22,588 -4, 344 Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1

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5 - 58 It is worth noting that the emission reductions shown in Table 5 - 75 are not incremental to the emissions reductions projected in the Phase 1 rulemaking. This is because the agencies have revised their assumptions about the adoption rate of APUs. This proposal assumes that without the proposed Phase 2 program (i.e., in the Phase 2 reference case), the APU adoption rate will be 30 percent for model ye ars 2010 and later , which is the value used in the Phase 1 reference case. This decision was based on the agencies’ assessment of how the current level of automatic engine shutdown and idle reduction technologi es are used b y the tractor manuf acturers to compl y with the 2014 model year CO 2 

### and fuel consumption standards. To date, the manufacturers are meeting the 2014 model year standards without the use of this technology . Compared to Phase 1, the proposed program projects much delayed penetration of APUs starting in model year 2021 ( Figure 5 - 4 ).

**Figure 5**  **- 4**  **Com parison of Assumed APU Use**  **during Extended Idle in Phase 1 and Phase 2** 

### Considering the change in assumption s about APU use and the magnitude of impact of APUs on criteria emissions , EPA conducted an analysis estimating the combined emissions impacts of the Phase 1 and proposed Phase 2 programs for NO X 

### , VOC, SO X 

### and PM 2.5 

### in calendar year 2050. The anal ys is estimated the combined Phase 1 and Phase 2 emissions impacts by comparing the Phase 2 control case inventories to the Phase 1 reference case inventories . To be consistent with the emissions modeling done for this proposed program, the emissions inventories for Phase 1 reference case were estimated using MOVES2014 . S 

### The results are shown in Table 5 - 78 . The differences in downstream reduction estimates between

S The emissions modeling for Phase 1 was performed using MOVES2010a.

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5 - 59 Phase 2 alone ( Table 5 - 75 ) and combined P hase 1 and Phase 2 ( Table 5 - 78 ) reflect the improvements in road loads from Phase 1. For NO X 

### and PM 2.5 

### only, we also estimated the combined Phase 1 and Phase 2 downstream and upstream emissions impacts for calendar ye ar 2025, and project that the two rules combined would reduce NO X 

### by up to 120,000 tons and PM 2.5 

### by up to 2,000 tons in that year. **Table 5**  **- 78**  **Combined Phase 1 and Phase 2**  **Annual Downstream Reductions of Heavy** **- Duty Criteria** 

**Emissions in Calendar Year 2050 using Analysis Method B**  **a** CY NO X VOC SO X PM 2.5 b 2050 403,915 69,415 2,111 - 1,890 Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1 b Negative reduction reflects an increase in emissions . 

### 5.5.2.1.2 Upstream Impacts The proposed program is projected to provide emissions reductions in all pollutants associated with upstream from production and distribution as the projected fuel savings reduce the demands for gasoline and diesel. Table 5 - 79 and Table 5 - 80 summarize the annual upstream reductions of preferred alternative and Alternative 4 for criteria pollutants and individual air toxic pollutants in calendar years 2025, 2035 and 2050 , relative to Alternative 1a . The results are shown both in changes in absolute tons and in percent reductions from the less dy namic reference to alternatives for the heavy- duty sector. **Table 5**  **- 79**  **Annual Upstream Impacts**  **of Heavy -** **Duty Non -**  **GHG Emissions in**  **Calendar Years 2025,**  **2035 and**

**2050 –**  **Preferred Alternative vs. Alt 1a using Analysis Method B**  **a** POLLUTANT CY2025 CY2035 CY2050

US Short Tons % Reduction US Short Tons % Reduction US Short Tons % Reduction 1,3 -Butadiene - 1 - 5.0 % -4 - 15.3 % - 5 - 18.4 % Acetaldehyde -4 - 3.0 % - 18 - 11.9 % - 26 - 14.6 % Acrolein - 0.5 - 3.4 % - 2 - 12.7 % - 3 - 15.5 % Benzene - 24 - 3.8 % - 92 - 13.4 % - 132 - 16.3 % CO - 3,798 -4.9 % - 13,001 - 15.3 % - 18,772 - 18.4 % Formaldehyde - 19 -4.7 % - 67 - 14.9 % - 98 - 18 .0% NO X - 9,282 -4.9 % - 31,782 - 15.3 % -45,888 - 18.4 % PM 2.5 - 1,020 -4.9 % - 3,514 - 15.2 % - 5,072 - 18.2 % SO X - 5,817 -4.9 % - 19,902 - 15.3 % - 28,736 - 18.4 % VOC - 3,283 - 3.7 % - 12,724 - 13.2 % - 18,214 - 16.1 % Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1

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5 - 60 **Table 5**  **- 80**  **Annual Upstream Impacts of Heavy -** **Duty Non -**  **GHG Emissions in Calendar Years 2025, 2035 and 2050**  **– Alternative 4 vs. Alt 1a using Analysis Method B**  **a** POLLUTANT CY2025 CY2035 CY2050

US Short Tons % Reduction US Short Tons % Reduction US Short Tons % Reduction 1,3 -Butadiene - 1 - 6.1% -4 - 15.9% - 5 

### - 18.4 % Acetaldehyde - 6 -4.3% - 20 - 12.6% - 26 - 14.7% Acrolein - 1 -4.7% - 2 - 13.3% - 3 - 15.5% Benzene - 32 - 5.0% - 97 - 14.0% - 133 - 16.3% CO -4,661 - 6.1% - 13,485 - 15.9% - 18,812 - 18.4% Formaldehyde - 24 - 5.9% - 70 - 15.5% - 97 - 18.0% NO X - 11,393 - 6.1% - 32,965 - 15.9% -45,986 - 18.4% PM 2.5 - 1,256 - 6.0% - 3,647 - 15.7% - 5,083 - 18.3% SO X - 7,137 - 6.1% - 20,641 - 15.9% - 28,797 - 18.4% VOC -4,342 -4.9% - 13,326 - 13.8% - 18,273 - 16.1% Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1 

### 5.5.2.1.3 Total Impacts As shown in Table 5 - 81 and Table 5 - 82 , the agencies estimate that this proposed program and Alternative 4 would result in overall net reductions of NO X 

### , VOC, SO X 

### , CO, PM 2.5 

### , and air toxics emissions . The downstream increase in PM 2.5 

### due to APU use is expected to be more than offset by reductions in PM 2.5 

### from upstream. T 

### The results are shown both in changes in absolute tons and in percent reductions from the less dy namic reference to the alternatives for the heavyduty sector. By

2050, the total impacts of the proposed program and Alternative 4 on criteria pollutants and air toxics are indistinguishable.

T Although a net reduction in PM 2.5 is expected at the national level, it is unlikely that the geographic location of increases in downstream PM 2.5 emissions will coincide with the location of decreases in upstream PM 2.5 emissions. For the final rule making, a national - scale air quality modeling analysis will be performed to estimate the future year am bient PM 2.5 concentrations for 2040. For further details, see Section VIII.D of this preamble and Chapter 8 of the draft RIA.

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5 - 61 **Table 5**  **- 81**  **Annual Total Impacts**  **(Upstream and Downstream** **) of Heavy -** **Duty Non -**  **GHG Emissions in**  **Calendar Years 2025,**  **2035 and 2050**  **– Preferred Alternative vs. Alt 1a usi**  **ng Analysis Method B a**  POLLUTANT CY2025 CY2035 CY2050

US Short Tons % Reduction US Short Tons % Reduction US Short Tons % Reduction 1,3 -Butadiene - 9 - 2.7 % - 25 - 15.1 % - 36 - 19.4 % Acetaldehyde - 674 - 10.1 % - 1,902 - 30.5 % - 2,697 - 36.0 % Acrolein - 97 - 9.8 % - 274 - 31.3 % - 388 - 36.9 % Benzene - 149 - 5.4 % -445 - 18.8 % - 633 - 22.9 % CO - 29,622 - 1.9 % - 85,961 - 6.6 % - 122,659 - 8.4 % Formaldehyde - 2,121 - 11.4 % - 5,978 - 31.7 % - 8,475 - 37.0 % NO X - 102,502 - 7.2 % - 298,907 - 26.6 % -426,610 - 32.1 % PM 2.5 - 386 - 0.6 % - 1,883 -4.2 % - 2,815 - 5.4 % SO X - 6,070 -4.9 % - 20,777 - 15.3 % - 30,000 - 18.4 % VOC - 16,724 - 5.6 % - 52,872 - 18.8 % - 75,521 - 22.7 % Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1 **Table 5**  **- 82**  **Annual Total Impacts (Upstream and Downstream** **) of Heavy -** **Duty Non -**  **GHG Emissions in Calendar Years 2025, 2035 and**  **2050 –**  **Alternative 4 vs. Alt 1a using Analysis Method B a**  POLLUTANT CY2025 CY2035 CY2050

US Short Tons % Reduction US Short Tons % Reduction US Short Tons % Reduction 1,3 -Butadiene - 9 - 2.8% - 26 - 15.2% - 36 - 19.4% Acetaldehyde - 676 - 10.1% - 1,903 - 30.6% - 2,697 - 36.0% Acrolein - 97 - 9.8% - 274 - 31.3% - 388 - 36.9% Benzene - 157 - 5.7% -450 - 18.9% - 634 - 22.9% CO - 30,580 - 1.9% - 86,526 - 6.6% - 122,703 - 8.4% Formaldehyde - 2,125 - 11.4% - 5,980 - 31.7% - 8,476 - 37.0% NO X - 106,180 - 7.4% - 301,339 - 26.8% -426,796 - 32.1% PM 2.5 - 646 - 1.1% - 2,036 -4.6% - 2,827 - 5.4% SO X - 7,450 - 6.1% - 21,550 - 15.9% - 30,064 - 18.4% VOC - 18,652 - 6.2% - 53,966 - 19.2% - 75,621 - 22.7% Note: a For an explanation of analytical Methods A and B, please see Preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Preamble Section X.A.1 

### 5.5.2.2 **Model Year Lifetime Analysis**  In addition to the annual non - GHG emissions reductions expected from the proposed rules and Alternative 4 , the combined ( downstream and upstream) non - GHG impacts for the lifetime of the impacted vehicles were estimated by heavy- duty vehicle category . Table 5 - 83

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5 - 62 show s the fleet-wide reductions of NO X 

### , PM 2.5 

### and SO X 

### from the preferred alternative and Alternative 4, relative to Alternative 1a , through the lifetimeU 

### of heavy- duty vehicles. **Table 5**  **- 83**  **Lifetim e**  **Non -**  **GHG Reductions by Heavy** **- Duty Vehicle Category**  **– Summary for Model Years**  **2018 -**  **2029 using Analysis Method**  **B (US Short Tons)**  **a**

ALTERNATIVE 3 (PROPOSED) ALTERNATIVE 4 NO -ACT ION ALTERNATIVE (BASELINE) 1a (Less Dynamic) 1a (Less Dynamic) NO X 2,399,990 2,459,497 HD Pickups and Vans 18,024 21,698 Vocational 15,810 24,265 Tractor/Trailers 2,366,156 2,413,534 PM 2.5 15,206 19,151 HD Pickups and Vans 2,342 2,796 Vocational 2,509 3,421 Tractor/Trailers 10,355 12,934 SO X 169,436 189,904 HD Pickups and Vans 13,301 15,688 Vocational 17,295 22,416 Tractor/Trailers 138,840 151,800 Note: a For an explanation of analytical Methods A and B, please see Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline , 1b, please see Section X.A.1.

U A lifetime of 30 years is assumed in MOVES.

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5 - 63 

## References 1 Intergovernmental Panel on Climate Change Working Group I. 2007. Climate Change 2007

– The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental P anel on Climate Change (IPCC). 2 U.S. EPA. 2014. Inventory of U.S. Greenhouse Gas Emissions and Sinks: 1990 - 2012. EPA 430 - R- 14 - 003. Available at http://www.epa.gov/climatechange/Downloads/ghgemissions/US - GHG - Inventory- 2014 - Main - Text.pdf 3 U.S. EPA. 2009. Technical Support Document for Endangerment and Cause or Contribute Findings for Greenhouse Gases under Section 202(a) of the Clean Air Act. Washington, DC. pp. 180 - 194. Available at http://epa.gov/climatechange/endangerment/downloads/Endangerment%20TSD.pdf 4 U.S. EPA. 2014. Inventory of U.S. Greenhouse Gas Emissions and Sinks: 1990 - 2012. EPA 430 - R- 14 - 003. Available at http://www.epa.gov/climatechange/Downloads/ghgemissions/US - GHG - Inventory- 2014 - Main - Text.pdf 5 MOVES2014 homepage: http://www.epa.gov/otaq/models/moves/index.htm 6 Argonne National Laboratory. The Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation (GREET) Model versions 1.8.c. http://www.transportation.anl.gov/modeling_simulation/GREET/ . 7 2007 Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report (AR4) 8 MOVES2014 homepage: http://www.epa.gov/otaq/models/moves/index.htm 9 Memorandum to the Docket “Runspecs , Model Inputs , MOVES Code and Database for HD GHG Phase 2 NPRM Emissions Modeling” Docket No. EPA- HQ - OAR- 2014 - 0827 10 U.S. EPA. Draft Regulatory Impact Analysis: Changes to Renewable Fuel Standard Program. Chapters 2 and 3. May 26, 200 9. Docket No. EPA - HQ - OAR- 2009 - 0472 - 0119 11 2017 and Later Model Year Light- Duty Vehicle Greenhouse Gas Emissions and Corporate Average Fuel Economy Standards (77 FR 62623, October 15, 2012) 12 Greenhouse Gas Emissions Standards and Fuel Efficiency Standards for Medium- and Heavy- Duty Engines and Vehicles (76 FR 57106, September 15, 2011) 13 Memorandum to the Docket “Upstream Emissions Modeling Files for HDGHG Phase 2 NPRM ” Docket No. EPA- HQ - OAR- 2014 - 0827 14 U.S. EPA. 2015. Population and Activity of On -road Vehicles in MOVES2014

– Draft Report” Docket No. EPAHQ - OAR- 2014 - 0827 . 15 Annual Energy Outlook 2014. http://www.eia.doe.gov/oiaf/aeo/ 16 U.S. EPA. 2015. “Exhaust Emission Rates for Heavy- Duty On-road Vehicles in MOVES2014

– Draft Report” Docket No. EPA- HQ - OAR- 2014 - 0827 . 17 Memorandum to the Docket “NPRM - Tractor- Trailer Inputs to MOVES” Docket No. EPA - HQ - OAR- 2014 - 0827 18 ACT Research Co., LLC. U.S. Trailers Monthly Market Indicators. Available at www.actresearch.net/report s Accessed 7/28/2014 19 U.S. Census Bureau. 2002 Vehicle Inventory and Use Survey. Available at https://www.census.gov/svsd/www/vius/2002.html Accessed 6/30/2014 20 Memorandum to the Docket “NPRM - Vocational Inputs to MOVES” Docket No. EPA - HQ - OAR- 2014 - 0827 21 Craig Harvey, EPA, “Calculation of Upstream Emissions for the GHG Vehicle Rule.” 2009. Docket No. EPAHQ - OAR- 2009 - 0472 - 0216 22 The Minnesota refrigerant leakage data: http://www.pca.state.mn.us/climatechange/mobileair.html#leakdata 23 Eastern Research Group. “A Study of R134a Leaks in Heavy Duty Vehicles.” CARB Contract 06 - 342. Presented during CARB Seminar on January 6, 2011.