This chapter assesses the effects on air quality from implementation of the Preferred Alternative as described in this Tier 1 Final Environmental Impact Statement (Tier 1 Final EIS). Human activity affects ambient air quality via production of air pollutants, including emissions by mobile and stationary sources. Mobile-source emissions refer to emissions from transportation sources. Stationary source emissions refer to emissions from fixed facilities. The No Action Alternative and Preferred Alternative could affect air emissions and greenhouse gas (GHG) emissions - and thus air quality - via operational changes in the following:
The summation of these changes will reflect the overall impact of the Preferred Alternative on the following:
The FRA used MOVES2010b1 to ensure consistent modeling between the analysis for the Tier 1 Draft EIS Action Alternatives (Volume 2) and the subsequent analysis for the Tier 1 Final EIS Preferred Alternative (Volume 1). MOVES2014 (or the most current model) will be used for subsequent Tier 2 project analyses.
Volume 2, Chapter 7.14 and Appendix E.14, provide background and more detailed information on terms related to air quality, attainment status, monitoring data, and the effects-assessment methodology used.
Analysis indicates that implementation of the Preferred Alternative would result in net benefits to air quality within the Study Area. The FRA's modeling predicts a decrease in regional pollutant burdens from roadways caused by the expected decrease in roadway VMT (autos) and an increase in regional pollutant burdens from power sources (diesel fuel and electric) due to increased train service under the Preferred Alternative. The combined (net) effect of these elements is a predicted decrease in all criteria pollutant burdens, with the exception of SO2. The predicted reduction in roadway VMT associated with the Preferred Alternative also results in an overall beneficial effect on mobile-source air toxics (MSAT). Overall, the net total GHG would decrease under the Preferred Alternative.
As required by the Clean Air Act (CAA), the U.S. Environmental Protection Agency (EPA) publishes a list of all geographic areas in compliance and not attaining the National Ambient Air Quality Standards (NAAQS) (nonattainment areas) for each criteria pollutant. Table 7.13-1 summarizes these standards. Areas that have insufficient data to make a determination are deemed unclassified, and are treated as being attainment areas until proven otherwise. Maintenance areas were previously designated as nonattainment for a particular pollutant but have since demonstrated compliance with the NAAQS for that pollutant. An area's designation is based on the data collected by the state monitoring network on a pollutant-by-pollutant basis. Table 7.13-2 lists all counties within the Affected Environment and identifies those that are nonattainment or maintenance for at least one pollutant. Table 7.13-3 lists the major sources of these pollutants. Volume 2, Appendix E.13, contains detailed ambient air quality monitoring data for the Study Area and attainment status information as well as current and future energy profiles.
Almost every county within the Affected Environment of the Preferred Alternative is nonattainment or maintenance for at least one pollutant. However, all counties in Rhode Island are attainment for all criteria pollutants.
Below is information about the attainment status of counties through which new or upgraded segments (off of the Existing NEC) of the Preferred Alternative run:
|Pollutant||Primary / Secondary||Averaging Time||Level||Form|
|Carbon Monoxide||Primary||8 hours||9 ppm||Not to be exceeded more than once per year|
|1 hours||35 ppm|
|Lead||Primary and Secondary||Rolling 3-month average||0.15 μg/m3 (1)||Not to be exceeded|
|Nitrogen Dioxide||Primary||1 hour||100 ppb||98th percentile, averaged over 3 years|
|Annual||53 ppb (2)||Annual Mean|
|8 hours||0.070 ppm (3)||Annual fourth-highest daily maximum 8-hr concentration, averaged over 3 years|
|Particle Pollution||PM2.5||Primary||Annual||12 μg/m3||Annual mean, averaged over 3 years|
|Secondary||Annual||15 μg/m3||Annual mean, averaged over 3 years|
|Primary and secondary||24 hours||35 μg/m3||98th percentile, averaged over 3 years|
|24 hours||150 μg/m3||Not to be exceeded more than once per year on average over 3 years|
|Sulfur Dioxide||Primary||1-hour||75 ppb (4)||99th percentile of 1-hour daily maximum concentrations, averaged over 3 years|
|Secondary||3 hours||0.5 ppm||Not to be exceeded more than once per year|
Nonattainment or Maintenance for at least one criteria pollutant?
|Existing NEC + Hartford / Springfield Line||Preferred Alternative|
|D.C.||Mobile||Solvent||Mobile||Dust||Fuel combustion||Fuel combustion|
|MD||Prince George's||Mobile||Biogenics||Mobile||Dust||Fuel combustion||Fuel combustion|
|DE||New Castle||Mobile||Mobile||Mobile||Dust||Fuel combustion||Fuel combustion|
|PA||Delaware||Mobile||Mobile||Mobile||Dust||Fuel combustion||Fuel combustion|
|NJ||Mercer||Mobile||Biogenics||Mobile||Dust||Fuel combustion||Fuel combustion|
|NY||New York||Mobile||Solvent||Mobile||Fuel combustion||Fuel combustion||Fuel combustion|
|CT||Fairfield||Mobile||Mobile||Mobile||Dust||Fuel combustion||Fuel combustion|
|RI||Washington||Mobile||Biogenics||Mobile||Dust||Fuel combustion||Fuel combustion|
The FRA's modeling predicts a decrease in regional pollutant burdens from roadways caused by the expected decrease in roadway VMT (autos) and an increase in regional pollutant burdens from power sources (diesel fuel and electric) due to increased train service under the Preferred Alternative. As shown in Table 7.13-4, the combined (net) effect of these elements is a predicted decrease in all criteria pollutant burdens, with the exception of SO2.
The primary reason for the increase in SO2 is the increased electrical power requirements resulting from additional trains under the Preferred Alternative. The predicted increase in SO2 would account for less than 0.1 percent of SO2 emission burdens currently generated in the Study Area. This relatively small change is expected to have little impact on overall ambient pollutant concentrations. In addition the vast majority of the Study Area is classified as attainment for SO2. However, these estimates for emission burdens generated by future power use are conservative since they are based on current emission profile information obtained from the EPA's eGRID and national emission inventory databases; in actuality, a cleaner energy profile will likely exist in the future due to the adoption or increase of renewable portfolio standards by the states within the Study Area. As shown in Table 7.13-5, all states within the Study Area have adopted renewable energy goals. For all states, achievement of these renewable energy targets are expected by 2040.
Refer to Volume 2, Appendix E.13, for a detailed methodology on the following future energy profile analysis.
The results presented in Table 7.13-6 reflect the impacts of the Preferred Alternative based upon this future emission profile for electrical generation. As shown in this table, the Preferred Alternative would have smaller absolute air quality impacts under a predicted future energy profile, as compared to the impacts expected if the energy profile were to remain the same as one that exists today. The reduced air quality impacts would result in an overall reduction in all criteria pollutant burdens, with the exception of SO2. The predicted increase in SO2 would account for less than 0.1 percent of SO2 emission burdens currently generated in the Study Area.
|Pollutant||Project Element||Preferred Alternative|
|Geography||Current Percentage of Renewable Energy||Percentage Renewable Energy Target||Percentage Increase Applied to Current Profile|
Several other items suggest that future energy profiles will continue to improve and result in fewer emissions:
The FRA did not conduct a quantitative analysis of the impacts to air quality from construction of the Preferred Alternative, since a detailed construction schedule, along with estimates of construction equipment and activities, are not developed as part of NEC FUTURE. However, construction of the Preferred Alternative would result in temporary emissions of criteria pollutants associated with construction equipment and activities. Local levels of criteria pollutants could also increase near station locations and parking facilities caused by vehicles queuing at these locations.
In addition to the criteria pollutants for which there are NAAQS, the EPA also regulates air toxics. Toxic air pollutants are those pollutants known or suspected to cause cancer or other serious health effects. Most air toxics originate from human-made sources, including on-road mobile sources, non-road mobile sources (e.g., airplanes), area sources (e.g., dry cleaners), and stationary sources (e.g., factories or refineries).
Refer to Volume 2, Chapter 7.13, for a detailed discussion on MSATs.
Reduction in roadway VMT results in an overall beneficial effect on MSAT. Although the No Action Alternative will not affect VMT in the Affected Environment, MSAT emissions will likely be lower than present levels in the design year; this reduction will be due to the EPA's national control programs, which are projected to reduce annual MSAT emissions by over 80 percent from 2010 to 2050.4 In addition to those reductions in annual MSAT emissions, the Preferred Alternative would reduce roadway VMT; therefore, a further reduction in MSAT would occur within the Affected Environment.
Construction of the Preferred Alternative could result in temporary, localized emissions of MSAT associated with construction equipment and activities. Local levels of MSAT could also increase near station locations and parking facilities.
To date, no national standards have been established regarding GHGs, nor has the EPA established criteria or thresholds for ambient GHG emissions pursuant to its authority to establish motor-vehicle emission standards for CO2 under the CAA. However, there is a considerable body of scientific literature addressing the sources of GHG emissions and their adverse effects on climate, including reports from the Intergovernmental Panel on Climate Change, the U.S. Global Change Research Program, the U.S. National Academy of Sciences, and the EPA as well as other federal agencies.
On February 18, 2010, the White House Council on Environmental Quality (CEQ) released draft guidance regarding the consideration of GHG in National Environmental Policy Act (NEPA) documents for federal actions; updated draft guidance was subsequently released in December 2014 (CEQ 2014). The 2014 draft guidance:
Furthermore, on August 1, 2016, the Council on Environmental Quality issued final guidance on consideration of GHG emissions and the effects of climate change in National Environmental Policy Act documents.5 This guidance states that "when addressing climate change agencies should consider: (1) The potential effects of a proposed action on climate change as indicated by assessing GHG emissions (e.g., to include, where applicable, carbon sequestration); and, (2) The effects of climate change on a proposed action and its environmental impacts." GHG emissions and the vulnerability of rail assets are considered in Chapter 7.15, Climate Change.
GHGs are different from other air pollutants evaluated in federal environmental reviews because their impacts are not localized or regional due to their rapid dispersion into the global atmosphere, which is characteristic of these gases. GHG emissions affect the entire planet. Table 7.13-7 highlights the total existing ambient GHG emissions from the commercial, electric power, residential, industrial and transportation sectors within the Study Area.
|Geography||Greenhouse Gas Emissions
(million metric tons C02)
Refer to Volume 2, Chapter 7.13, for a detailed explanation of GHGs.
Table 7.13-8 presents the changes in GHGs in the Study Area due to the implementation of the Preferred Alternative, in terms of CO2e, in the year 2040. The changes in CO2e are presented for roadways, diesel trains, and electric trains.
As shown in Table 7.13-8, CO2e from roadways would decrease under the Preferred Alternative, whereas the CO2e from electric trains would increase. Overall, the net total GHGs would decrease under the Preferred Alternative. For the No Action Alternative, changes in CO2e will reflect future regulations and VMT growth. As shown in Table 7.13-9, the CO2e reductions would be even greater assuming the future energy profile, due to the implementation of the Preferred Alternative.
Additionally, the EPA's Clean Power Plan,6 if implemented as finalized in October 2015, would reduce carbon pollution by 32 percent by 2030. The Supreme Court stayed implementation of the final rule in February 2016, pending judicial review of legal challenges. Despite the stay, some states are moving forward with compliance with the final rule, and the EPA is encouraging voluntary state action in compliance with the rule. States, including those in the Study Area, that have already invested in energy efficiency programs will be able to build on these programs to help make progress toward meeting their targets.
The use of regenerative braking, as described in Section 126.96.36.199, would reduce the energy use, and resulting power plant CO2e emissions, from the electric trains.
As discussed in Chapter 5, Transportation, investment in the NEC FUTURE passenger rail infrastructure would create a shift in demand from aircraft and bus trips servicing the corridor to rail trips, when comparing the No Action Alternative to the Preferred Alternative. This mode shift from aircraft and bus trips to rail trips would remove some aircraft and buses from the NEC. As such, CO2e from aircraft and buses would decrease under the Preferred Alternative.
The FRA did not conduct a quantitative analysis of the impacts to air quality of construction of the Preferred Alternative, as a detailed construction schedule, along with estimates of construction equipment and activities, are unknown at the Tier 1 level. However, construction of the Preferred Alternative would result in temporary CO2e emissions associated with construction equipment and activities.
Overall, the reductions in criteria pollutants under the Preferred Alternative would be greater than the reductions under the Action Alternatives. The only exception is SO2, with Alternatives 1 and 2 performing better than the Preferred Alternative. The reductions in CO2e under the Preferred Alternative would also be greater than the reductions under the Action Alternatives.
Examples of programmatic mitigation measures for air quality include the incorporation of Environmental Performance Measures in Tier 2 alternatives, including solar panels on stations and other buildings, as well as the use of renewable energy. With regards to construction activities, potential mitigation could involve voluntary emission reduction agreements, as well as the use of electric, energy efficient or low-emissions equipment. Specific mitigation concerning air quality impacts during construction, such as fugitive dust from earth moving and pollutants from construction equipment, would also be investigated. The following are examples of potential mitigation measures:
Project-level Tier 2 analyses will include more-detailed evaluation of site-specific air quality impacts, where appropriate, as well as updated and refined regional and GHG analyses, as appropriate. Subsequent Tier 2 analyses will determine the benefits at the individual project level. The EPA has requested that subsequent Tier 2 project analyses also examine the effects of idling freight trains to the extent practicable. Part of the Tier 2 analyses will include the following:
1 The FRA calculated vehicle emission factors using the EPA's MOVES2010b mobile-source emissions modeling program, which estimates emissions and GHGs for mobile sources.
2 Federal Register,Vol. 80, No. 205 (October 2015). Accessed at https://www.gpo.gov/fdsys/pkg/FR-2015-10-23/pdf/2015-22842.pdf
3 The FRA recognizes that the Supreme Court stayed implementation of the Clean Power Plan in February 2016, pending judicial review of legal challenges to the rule. This analysis assumes that states will continue to voluntarily comply with the Clean Power Plan during the stay and that the Clean Power Plan will be upheld.
4 Federal Highway Administration. (2013, February 2). Interim Guidance Update on Mobile Source Air Toxic Analysis in NEPA - Appendix B. Retrieved from Air Quality: Transportation and Toxic Air Pollutants: http://www.fhwa.dot.gov/environment/air_quality/air_toxics/policy_and_guidance/aqintguidapb.cfm
5 Council on Environmental Quality, "Final Guidance for Federal Departments and Agencies on Consideration of Greenhouse Gas Emissions and the Effects of Climate Change in National Environmental Policy Act Reviews," 81 Fed. Reg. 51866 (August 5, 2016). Access at http://energy.gov/sites/prod/files/2016/08/f33/nepa_final_ghg_guidance_FR.pdf
6 Federal Register, Vol. 80, No. 205 (October 2015). Accessed at https://www.gpo.gov/fdsys/pkg/FR-2015-10-23/pdf/2015-22842.pdf
7 U.S. Environmental Protection Agency. (2013). Transportation Conformity Guidance for Quantitative Hot-Spot Analyses in PM2.5 and PM10 Nonattainment and Maintenance Areas. Retrieved fromhttp://www.epa.gov/otaq/stateresources/transconf/policy/420b13053-sec.pdf
8 U.S. Environmental Protection Agency. (2010). Using MOVES in Project-Level Carbon Monoxide Analyses. Retrieved fromhttp://www.epa.gov/otaq/stateresources/transconf/policy/420b10041.pdf
11 U.S. Environmental Protection Agency. Preferred/Recommended Models. Retrieved from http://www.epa.gov/scram001/dispersion_prefrec.htm