7-1 June 2021

Air Quality, Greenhouse Gas Emissions,

Chapter 7: and Resilience

7.1 INTRODUCTION 

Emissions from stationary sources, mobile sources, and construction sources, all have the 

potential to affect air quality. This chapter presents the analysis of the potential constructionrelated and operational effects of the No Action Alternative and the Preferred Alternative on air 

quality emissions in the Study Area in accordance with transportation and general conformity 

requirements of the Clean Air Act (CAA).

This chapter also presents the analysis of the effects of the Preferred Alternative on greenhouse 

gas (GHG) emissions, and discusses the Preferred Alternative’s conformity to the current New 

York City and New York State emission reduction goals and policies as laid out in OneNYC and 

the Climate Leadership and Community Protection Act (CLCPA), respectively. In addition, this 

chapter includes an analysis of the effects of climate change on the Preferred Alternative related 

to resilience to future severe weather events, and the effects of climate change from the Preferred 

Alternative due to GHG emissions generated by the construction and operation of the Preferred 

Alternative. 

7.2 REGULATORY FRAMEWORK

In accordance with the CAA (42 U.S.C. § 7401 et seq.), the United States Environmental 

Protection Agency (USEPA) established primary and secondary National Ambient Air Quality 

Standards (NAAQS) for six criteria air pollutants: carbon monoxide (CO), nitrogen dioxide (NO2), 

ozone, respirable particulate matter (PM) [both PM2.5 and PM10], sulfur dioxide (SO2), and lead. 

The primary standards represent levels that are requisite to protect the public health, allowing an 

adequate margin of safety. The secondary standards are intended to protect the nation’s welfare, 

and account for air pollutant effects on soil, water, visibility, materials, vegetation, and other 

aspects of the environment. The CAA, as amended in 1990, includes a definition for nonattainment areas (NAA) which are geographic regions that do not meet one or more of the NAAQS. 

When an area is designated as non-attainment by USEPA, the state is required to develop and 

implement a State Implementation Plan (SIP), which identifies how a state plans to attain and 

maintain compliance with the NAAQS under the deadlines established by the CAA. Table 7-1

summarizes the attainment status in New York City. 

The general conformity requirements of the CAA and its implementing regulations (40 CFR part 

93 subpart B) limit the ability of federal agencies to assist, fund, permit, and approve projects in 

non-attainment and maintenance areas where the action’s direct and indirect emissions have the 

potential to impact one or more of the six criteria air pollutants or their precursor pollutants at rates 

equal to or exceeding prescribed de minimis thresholds.
June 2021 7-2 

Table 7-1 

Attainment Status in New York City 

Pollutant Averaging Period Attainment Status

CO 1-Hour, 8-Hour Attainment1

PM10 24-Hour Non-attainment (Moderate)

PM2.5 Annual, 24-Hour Attainment2

O3 8-Hour Non-attainment (Serious)

NO2 Annual, 1-Hour Attainment, Unclassified

SO2 1-Hour Attainment

Notes: 

1 USEPA redesignated the New York City Metropolitan area as in attainment for the 1-hour and 8-hour CO 

NAAQS in 2002. The area is currently under a second maintenance plan. 2 USEPA redesignated the New York area as in attainment for the 1997 annual and 24-hour NAAQS 

effective April 18, 2014. The area is now under maintenance plans.

As discussed in the CEQR Technical Manual,

1

1 New York City Mayor’s Office of Environmental Coordination. CEQR Technical Manual. December, 2020.

climate change is projected to have wide‐ranging 

effects on the environment, including rising sea levels, increases in temperature, and changes in 

precipitation levels. Although this is occurring on a global scale, the environmental effects of 

climate change are also likely to be felt at the local level. New York State and New York City have 

each established sustainability initiatives and goals for greatly reducing GHG emissions and for 

adapting to climate change.

Per the CEQR Technical Manual, the citywide GHG reduction goal is currently the most 

appropriate standard by which to analyze a project under CEQR. The CEQR Technical Manual 

recommends that a GHG consistency assessment be undertaken for any project preparing an 

environmental impact statement expected to result in the greatest potential to produce GHG 

emissions that may result in inconsistencies in the City’s GHG reduction goal. Accordingly, a GHG 

consistency assessment is provided. 

Additionally, the CEQR Technical Manual recommends the potential effects of global climate 

change on the proposed project are also considered for project with portions of the proposed 

project constructed or operated within the current and/or future floodplain. 

The pollutants for analysis, the NAAQS, attainment status and state implementation plan, and the 

transportation and general conformity requirements of the CAA are all described in detail in 

Appendix B, “Methodology Report,” Chapter 4, “Air Quality, Greenhouse Gas Emissions, and 

Resilience,” Section A, “Pollutants for Analysis,” and Section B, “Regulatory Context.”

7.3 ANALYSIS METHODOLOGY

This EIS analyzed the potential for local air quality impacts from operational and constructionrelated sources at sensitive locations within a Study Area extending to at least 400 feet from the 

Project Site. The Study Area for mobile sources relates directly to the Study Area used for the 

construction transportation analysis presented in Chapter 6, “Transportation.” The Study Area for 

this resource category includes the Project Site and extends outward to include routes for travel 

of construction workers, materials, and services, and represents the distance that, based on 

CEQR Technical Manual guidelines, defines the area in which the Preferred Alternative could 

cause impacts. The Study Area is consistent with study areas for the environmental analysis of 

similar projects in New York City.
Chapter 7: Air Quality, Greenhouse Gas Emissions, and Resilience

7-3 June 2021

Please see Appendix B, Chapter 4, for a complete description of the operational and construction 

air quality analysis methodology for this resource category, and Appendix D, “Air Quality,” for 

further discussion of modeling parameters used for the air quality analyses.

7.3.1 OPERATIONAL AIR QUALITY

The potential for air quality impacts associated with emission sources were analyzed for the No 

Action Alternative and the Preferred Alternative. 

The primary emission sources evaluated are emissions associated with fossil fuel-fired systems 

that are part of the Preferred Alternative. This includes fossil fuel-fired equipment and 

infrastructure related to life-safety and ventilation components of the Platform and its associated 

infrastructure (such as venting of diesel locomotive emissions from the area below the Platform). 

Life-safety equipment generally operates in the event of an emergency involving the loss of utility 

electrical power, or for periodic testing for short periods to ensure the reliability and availability of 

the equipment in the event of an actual emergency. The dual-mode (diesel-electric) locomotives 

serving LIRR stations without electric rail infrastructure entering Penn Station in the morning would

continue to idle in diesel mode under the proposed Platform in the Western Rail Yard until 

departing Penn Station in the evening. Additionally, locomotives would perform a 15-minute test 

of the diesel engine at higher load levels before departing. While under the Platform, hoods 

integrated into a dedicated ventilation system to prevent emissions from dispersing in the area 

below the Platform would capture locomotive engine exhaust. Diesel-fueled delivery, 

maintenance, and garbage trucks would also continue to operate in the yard. However, these 

vehicles would operate intermittently as needed. The Preferred Alternative includes a proposed 

mechanical ventilation system that would exhaust these emissions above the Platform. 

The analysis provides the potential air quality impacts of these emissions, as described in detail 

below. The locations of all modeled ventilation exhaust louvers and receptors included in the air

quality analysis are shown in Figure 7-1. 

7.3.1.1 LIFE SAFETY EQUIPMENT

As discussed in Appendix D, FRA estimated that emissions from the diesel generators would be 

minor on an annual basis due to their limited usage, and are not anticipated to result in a significant 

effect on ambient concentrations. Furthermore, USEPA has determined that emission sources, such 

as emergency generators normally only operated intermittently for testing, as not having a significant 

effect on 1-hour average ambient concentrations of NO2 and SO2.

2

2 USEPA, Additional Clarification Regarding Application of Appendix W Modeling for the 1-hour NO2 National 

Ambient Air Quality Standard, March 11, 2011. 

Therefore, FRA concluded that 

further analysis of air quality impacts from the proposed life safety generators was not warranted. 
!

!

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W 30th St

W 29th St

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W 35th St

W 33rd St

Joe Dimaggio Hwy Twelfth Ave

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lvd E

W 28th St

HUDSON

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NE

Fan

Plant

SE

Fan

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WESTERN RAIL YARD INFRASTRUCTURE PROJECT

Air Quality Source and Receptor Locations

Figure 7-1

0 200 FEET

11.16.20

Project Site (Western Rail Yard) A

Study Area (400-foot perimeter)

Fan Plant

Receptor Location

!

Source Location
June 2021 7-4 

7.3.1.2 PLATFORM VENTILATION SYSTEM

As discussed in Appendix D, short-term and annual emission rates were estimated (see Table 

7-1) from the proposed ventilation system associated with localized exhaust hoods placed over 

locations where LIRR dual-mode locomotives would park in the railyard. The estimates of shortterm and annual emission rates were based on LIRR projections that the types and sizes of 

engines currently operating would remain in operation in the future as well as anticipated daily 

train schedules provided by LIRR. Based on previous information provided by LIRR, FRA 

assumed that LIRR’s dual-mode locomotives would operate engines primarily at a low idle load 

while being stored at the Western Rail Yard (between the hours of 6 AM and 3 PM) and would 

perform 15-minute pre-run testing for each engine before departing Penn Station (between 3 PM 

and 6 PM). FRA calculated emission rates associated with the pre-run testing using a 

representative time distribution among engine load levels to determine an average load level 

during the 15-minute period.

FRA conservatively assumed all locomotive emissions would vent through a single fan plant 

location; FRA performed an assessment at each of the three proposed fan plant locations (see 

Figure 7-1) in order to identify maximum potential air quality impacts. Additionally, FRA obtained 

stack parameters (stack height, diameter) shown in Table 7-2 for the ventilation exhausts from 

available design information.

Table 7-2 

Stack Parameters and Emission Rates 

Parameter Northeast Fan Plant Northwest Fan Plant Southeast Fan Plant

Exhaust Release Height (ft)(1) 30 30 30

Stack Exhaust Temp. (°F)(2) 70 70 70

Stack Exhaust Diameter (ft)(2) 2.82 3.57 3.09

Stack Exhaust Flow (ACFM)(3) 4,687 7,500 5,625

Stack Exhaust Velocity (ft/s)(4) 12.5 12.5 12.5

Emission Rate per Train (g/s)(5) Idle Locomotive Pre-Run Test Locomotive

NOx 1.85 x 10-2 5.13 x 10-1

CO 5.50 x 10-3 1.53 x 10-1

PM10 5.50 x 10-4 1.53 x 10-2

PM2.5 5.50 x 10-4 1.53 x 10-2

Notes:

(1) Exhaust release height is relative to the top of the constructed Platform.

(2) The stack diameter is representative of a circular stack of equivalent area as the exhaust louver.

(3) ACFM = actual cubic feet per minute.

(4) The stack exhaust flow rate was estimated based on the type of fuel and heat input rates.

(5) Emission rates are based on USEPA Tier I Line-Haul Locomotive Emission Standards.

7.3.2 CONSTRUCTION AIR QUALITY

Emissions from on-site construction equipment and on-road construction vehicles, as well as dustgenerating construction activities, have the potential to affect air quality. The construction air 

quality impacts included both on-site and on-road sources of air emissions, and the combined 

impact of both sources, where applicable. The analysis addresses both local (microscale) and 

regional (mesoscale) construction period emissions. 
Chapter 7: Air Quality, Greenhouse Gas Emissions, and Resilience

7-5 June 2021

In general, much of the heavy equipment used in construction is powered by diesel engines that 

produce relatively high levels of nitrogen oxides (NOx) and PM emissions. Fugitive dust generated 

by construction activities is also a source of PM emissions and gasoline engines produce relatively 

high levels of CO. Since USEPA mandates the use of ultra-low sulfur diesel (ULSD)3

3 USEPA required a major reduction in the sulfur content of diesel fuel intended for use in locomotive, marine, 

and non-road engines and equipment, including construction equipment. As of 2015, the diesel fuel produced 

by all large refiners, small refiners, and importers must be ULSD fuel, with sulfur levels in non-road diesel fuel

limited to a maximum of 15 ppm.

fuel for all 

highway and non-road diesel engines, sulfur oxides (SOx) emitted from the Preferred Alternative’s

construction activities would be negligible. Therefore, FRA analyzed NO2, a component of NOx

that is a regulated pollutant, along with PM10, PM2.5, and CO, for the local construction period 

analysis. The pollutants of concern on a regional basis are CO, PM10, PM2.5, NOx, SO2, and 

VOCs, and FRA analyzed these pollutants for the regional construction period analysis.

7.3.2.1 CONSTRUCTION MICROSCALE ANALYSIS

FRA predicted concentrations using the USEPA AERMOD dispersion model to determine the 

potential for air quality impacts during on-site construction activities and due to constructiongenerated traffic on local roadways. Concentrations for each pollutant of concern from

construction activities at each sensitive receptor were predicted during the most representative 

worst-case time period(s). The potential for adverse impacts was determined by comparing 

modeled concentrations to NAAQS, and modeled increments to applicable CEQR Technical 

Manual de minimis thresholds, as shown in Table 7-3. Please see Chapter 4 in Appendix B for a 

general description of the construction air quality analysis methodology for this resource category. 

Appendix D provides additional detail on the methodology and assumptions used for modeling.

Table 7-3 

CEQR Technical Manual De Minimis Thresholds 

Pollutant De Minimis Criteria

CO 

• An increase of 0.5 parts per million (ppm) or more in the maximum 8-hour average CO concentration at 

a location where the predicted No Action 8-hour concentration is equal to or between 8 and 9 ppm; or 

• An increase of more than half the difference between baseline (i.e., No Action) concentrations and the 

8-hour standard, when No Action concentrations are below 8.0 ppm.

PM2.5

• Predicted increase of more than half the difference between the background concentration and the 24-

hour standard; or 

• Annual average PM 2.5 concentration increments that are predicted to be greater than 0.1 μg/m3 at 

ground level on a neighborhood scale (i.e., the annual increase in concentration representing the 

average over an area of approximately 1 square kilometer, centered on the location where the maximum 

ground-level impact is predicted for stationary sources; or at a distance from a roadway corridor similar 

to the minimum distance defined for locating neighborhood scale monitoring stations); or 

• Annual average PM2.5 concentration increments that are predicted to be greater than 0.3 μg/m3 at a 

discrete or ground level receptor location.

Source: CEQR Technical Manual, Chapter 17, Section 412.

7.3.2.2 CONSTRUCTION MESOSCALE ANALYSIS 

FRA calculated emissions from on-road construction trucks and worker vehicles and from nonroad construction equipment on an annual basis for each year of the Preferred Alternative’s 

construction period. 
June 2021 7-6 

7.3.3 GREENHOUSE GAS EMISSIONS AND RESILIENCY

As discussed in Appendix D, FRA assessed GHG emissions generated by the construction and 

operation of the Preferred Alternative as well as the effect of climate change on the Preferred 

Alternative in terms of resilience to severe weather events under future conditions. Please see 

Chapter 4 in Appendix B for a general description of the analysis methodology for this resource 

category.

7.3.3.1 GREENHOUSE GAS EMISSIONS

As discussed above, on-site fossil fuel-fired equipment included in the Preferred Alternative would 

operate intermittently and was not included in the GHG analysis. Therefore, the analysis only 

includes emissions associated with electricity consumption required to operate the ventilation 

systems. FRA used an emission factor of 0.289 kg carbon dioxide equivalent (CO2e)4

4 CO2e emissions represent the quantity of each GHG weighted by its effectiveness using CO2 as a reference. 

This is achieved by multiplying the quantity of each GHG emitted by a factor called global warming potential 

(GWP).

per kWh 

based on New York City electrical consumption and the associated GHG emissions.5

5 The City of New York Mayor’s Office of Long-Term Planning and Sustainability. Inventory of New York City 

Greenhouse Gas Emissions in 2019. https://nyc-ghg-inventory.cusp.nyu.edu/ 

Since the 

Preferred Alternative would not substantially affect locomotive operation, FRA did not include 

emissions associated with locomotives in the analysis. 

The construction analysis included emissions associated with on-road vehicle and non-road 

equipment use, and emissions embedded in the materials used during construction. FRA has 

estimated these emissions based on specific estimates of construction activity provided by the 

Project Sponsor. 

7.3.3.2 RESILIENCE 

The Preferred Alternative would introduce critical infrastructure—the Platform and the Tunnel 

Encasement—with very long design lifespans (assumed to be greater than 100 years). 

Accordingly, FRA reviewed the Preferred Alternative in the context of climate scenarios projected 

for 2100. FRA also considered interim years (2050s, 2080s) for adaptive resilience design (i.e., 

considering potential future resilience measures if necessary, which may not be implemented by 

the 2026 operational analysis year). 

FRA considered flooding impacts on the Preferred Alternative as well as any potential impact for 

affecting other uses by reviewing the elevations of infrastructure and uses introduced by the 

Preferred Alternative. Furthermore, FRA considered relevant protection measures and identified

any potential vulnerabilities or potential flooding risks.

7.4 AFFECTED ENVIRONMENT

7.4.1 AIR QUALITY

Table 7-4 presents representative background concentrations of all criteria pollutants of concern 

for the air quality analysis within the Study Area. NYSDEC collects the concentrations at NYSDEC 

air quality monitoring stations nearest the Preferred Alternative in New York. Reported 

concentrations were calculated in a manner consistent with the definitions of the NAAQS for the 

relevant averaging period. As shown in the table, the monitored levels do not exceed the NAAQS.
Chapter 7: Air Quality, Greenhouse Gas Emissions, and Resilience

7-7 June 2021

Table 7-4 

Representative Monitored Ambient Air Quality Data 

Pollutant Location Units Averaging Period Concentration NAAQS

CO CCNY ppm 1-hour 1.68 35

CO CCNY ppm 8-hour 1.1 9

SO2 IS 52 μg/m3 1-hour 14.6 196

PM10 Division Street μg/m3 24-hour 43 150

PM2.5 Division Street μg/m3 Annual 9 12

PM2.5 Division Street μg/m3 24-hour 19.7 35

NO2 IS 52 μg/m3 Annual 31.7 100

NO2 IS 52 μg/m3 1-hour 110.6 188

Lead IS 52 μg/m3 3-month 0.0027 0.15

Ozone IS 52 ppm 8-hour 0.070 0.075

Notes: 

(1) The CO concentration for the short-term average is the second-highest from the most recent year with 

available data. 

(2) The PM10 concentration for the short-term average is the highest from the most recent year with 

available data.

(3) PM2.5 annual concentrations are the average of 2017–2019 annual concentrations, and the 24-hour 

concentration is the average of the annual 98th percentiles in the same period. 

(4) The SO2 1-hour and NO2 1-hour concentrations are the average of the 99th percentile and 98th 

percentile, respectively, of the highest daily 1-hour maximum from 2017 to 2019. 

(5) The lead concentrations are based on the highest quarterly average concentration measured in 2019.

(6) The ozone concentration is based on the 3-year average (2017–2019) of the 4th highest daily 

maximum 8-hour average concentrations.

Source: New York State Air Quality Report Ambient Air Monitoring System, NYSDEC, 2017–2019.

7.4.2 GREENHOUSE GAS EMISSIONS AND RESILIENCY

7.4.2.1 GREENHOUSE GAS EMISSIONS

The environment affected by GHG emissions includes the global atmospheric GHG 

concentrations and the long-term effect they have on the earth’s energy balance, the ensuing 

climatic conditions, and the resulting effect on many human and natural systems. Detailed 

information on this topic is not included in this EIS but is available in reference documents, such 

as the Intergovernmental Panel on Climate Change (IPCC)’s latest synthesis report,6

6 Climate Change 2014: Synthesis Report. Contribution of Working Groups I, II and III to the Fifth Assessment 

Report of the Intergovernmental Panel on Climate Change. Intergovernmental Panel on Climate Change. 2014.

the U.S. 

Third National Climate Assessment,

7

7 Climate Change Impacts in the United States: The Third National Climate Assessment. U.S. Global Change 

Research Program. October, 2014.

and the most recent New York City Panel on Climate Change 

(NPCC) report.

8

8 Advancing Tools and Methods for Flexible Adaptation Pathways and Science Policy Integration. New York City 

Panel on Climate Change 2019 Report. March, 2019.
June 2021 7-8 

7.4.2.2 RESILIENCY 

As discussed in Appendix D, FRA considered the existing climatic conditions in the Study Area 

related to sea level rise and storm surge, temperature and precipitation, and the locations of 

elements of the Preferred Alternative that could be affected by changes to these climatic 

conditions. The best, most recent, and most complete analysis of potential future climate 

conditions in the Study Area are those available from the NPCC. The following summarizes the 

NPCC’s findings that are most relevant to the Preferred Alternative.

7.4.2.2.1 Sea Level Rise and Storm Surge

The NPCC report characterizes the probability of increased sea levels as “extremely likely,” but 

there is uncertainty regarding the probability of the projected levels and timescale. In addition, the 

severity of storms is also likely to increase. Intense hurricanes are characterized as “more likely 

than not” to increase in intensity and/or frequency, and the likelihood of changes in other large 

storms (Nor’easters) are characterized as unknown. Therefore, the projections for future 1-percent 

probability coastal storm surge levels for the area include only sea level rise at this time, and do 

not account for changes in storm frequency.

NPCC analyzed three sea-level rise scenarios for each projection year: Low, Middle Range, and 

High. The Low scenario represents approximately a case in which sea level would continue to rise 

at the average rate it has been in recent decades. Most studies indicate that sea level rise is 

already accelerating, and the probability of this scenario is therefore unsuitable for most planning 

purposes. Note also that the High scenario, while representing the 90th percentile of current 

modeling, does not represent the potential worst-case scenario, and does not yet include 

additional factors being studied (such as accurate GHG emissions accounting, the effects on local 

weather patterns, the interaction with artic ice sheets and warming temperatures, etc.), which may 

lead to higher projections for the end of the century. The NPCC’s sea level rise estimates ranging 

from the high end of the Middle Range scenario to the High scenario indicate the following:

• 2080s: 39 to 58 inches

• 2100: 50 to 75 inches

There are two approaches to predicting future coastal flooding, accounting for the potential impact 

of sea level rise on storm surge: a static approach that adds sea level rise onto current storm tide 

levels, and a dynamic approach using models that capture the roles of friction and wind as well as 

sea level rise and tides. NPCC has studied the potential impact of sea level rise on storm surge, 

including a study of the effect of dynamic modeling. NPCC concluded that both static and dynamic 

modeling approaches are valid and reliable approximations of coastal flooding for most locations 

in the New York metropolitan region. FRA used the static approach for the assessment presented 

in this chapter.

Applying the static approach, potential future flood levels consist of the range of projected sea 

level rise from NPCC described above added to the Base Flood Elevation (BFE) for the specific 

area of concern. The Federal Emergency Management Agency (FEMA) defines the BFE as the 

currently projected 1-percent probability storm elevations available from the preliminary Flood 

Insurance Rate Map (FIRM). The 1-percent probability storm (sometimes referred to as the 100-

year storm) is a storm that has a 1 percent chance of occurring in any given year. The area that 

would be flooded in a 100-year storm is mapped by FEMA on its FIRMs. FEMA’s maps also 

indicate the BFE, which is the height of flooding that can be expected in the 1-percent probability 

storm within the floodplain. The BFE is measured not from ground or sea level, but from a 

benchmark called the North American Vertical Datum of 1988 (NAVD88) established by the 

National Oceanic and Atmospheric Administration, which holds fixed the height of the primary tidal 

benchmark because of variations in sea surface topography.
Chapter 7: Air Quality, Greenhouse Gas Emissions, and Resilience

7-9 June 2021

For the Preferred Alternative, the areas of concern for flooding in Manhattan are the areas of the 

Project Site within the current and future flood hazard area, which include: 

• The area of the below-grade tracks west of Penn Station under the proposed Platform that 

was flooded during Superstorm Sandy; and

• The proposed locations for the Northeast, Northwest and Southeast fan plants.

Potential future flood levels at these locations consist of the range of projected sea level rise from 

NPCC added to the BFE. The current BFE available from the preliminary FIRM9

9 FEMA. Flood Insurance Rate Map, New York County, New York—Preliminary. Panel 69 of 457. Map 

3604970069G. December 5, 2013.

is 12 feet NAVD88 

by the Northwest ventilation shaft and fan plant and 11 feet NAVD88 by the Northeast and 

Southeast fan plants.

As shown in Table 7-5, the resulting range of potential future flood elevations taking into account 

the current BFE and potential future sea level rise is up to 17 feet NAVD88 by the 2080s and up 

to 18 feet NAVD88 by 2100 at the Twelfth Avenue fan plant site, and up to 16 feet NAVD88 by the 

2080s and up to 17 feet NAVD88 by 2100 at the portal sites.

Table 7-5 

Projected Potential 1-Percent Annual Probability Flood Elevations 

Locations within the Study Area (feet NAVD88)

Site

Current 

Base 

Flood 

Elevation1

NPCC Projection 

of Future Flood 

Elevations 

(Middle to High 

Range)2 2020s 

(+8” to +10” over 

Current BFE)

NPCC Projection 

of Future Flood 

Elevations 

(Middle to High 

Range)2 2080s

(+39” to +58” over 

Current BFE)

NPCC Projection 

of Future Flood 

Elevations 

(Middle to High 

Range)2 2100

(+50” to +75” over 

Current BFE)

Northwest Fan Plant 11’ 12’ 14’ to 16’ 15’ to 17’

Northeast and Southeast and Fan Plants 12’ 13’ 15’ to 17’ 16’ to 18’

Sources:

1 FEMA, 2013.

2 NPCC, 2015.

7.4.2.2.2 Temperature 

NPCC projected that annual average temperature is extremely likely to increase. An average 

increase of up to 12oF by the end of the century was projected (less in some scenarios). 

Heatwaves (events with a duration of three or more days with maximum temperatures exceeding 

90oF) are very likely to increase in frequency, with up to nine events projected in the high estimate 

by the 2080s in an average year, up from two events per average year in the baseline, and a 

duration of up to eight days per event, up from four days in the baseline. The number of days per 

average year with a maximum temperature exceeding 90oF in that same timeframe could increase 

from 18 to 87.
June 2021 7-10

7.4.2.2.3 Precipitation

NPCC projected that annual average precipitation is likely to increase, with projections ranging up 

to 25 percent by the end of the century (less in some scenarios). The number of downpours 

(intense precipitation events shorter than a day and often shorter than an hour) is “very likely” to 

increase. By the 2080s, downpours of 1 inch or more could increase from an annual average of 

13 events in the baseline to 18 events, and downpours of 4 inches or more from an annual average 

of 0.3 to 0.7 events.

More recently, the Northeast Regional Climate Center (NRCC) has partnered with the New York 

State Energy Research and Development Authority (NYSERDA) to downscale global climate 

model output and create extreme precipitation projections for New York State and the surrounding 

area, including the downstate area and meteorological stations in northern New Jersey.10

10 Arthur T. DeGaetano, Christopher M. Castellano. Future projections of extreme precipitation intensity-durationfrequency curves for climate adaptation planning in New York State. Climate Services, Volume 5. January 2017.

Detailed 

data for each station are also available online.11

11 NRCC/NYSERDA Intensity Duration Frequency Curves for New York State: Future Projections for a Changing 

Climate. http://ny-idf-projections.nrcc.cornell.edu. Accessed May 2017.

Table 7-6 presents a summary of the projected 

increases in precipitation for nearby stations in New York for the return periods relevant to runoff 

and drainage design.

Table 7-6 

Projected Precipitation Increases, High Scenario 

New York Central Park, NY

Projection 

Period

Return Period1

100-Year (%)

Return Period1

25-Year (%)

Return Period1

10-Year (%)

Return Period1

5-Year (%)

2050s 27% 13% 11% 12%

2080s 39% 28% 23% 20%

Note:

1 The return period represents a probability of occurrence, and not an actual period of expected 

occurrence. The “100-year” represents a storm with a probability of occurrence of 1 percent in any given 

year. Similarly, “25-year” represents a 4 percent probability, and “10-year” represents a 10-percent 

probability in any given year.

Source: NRCC 2017

7.5 ENVIRONMENTAL CONSEQUENCES

FRA used the reports and recommendations described above to make a determination of potential 

effects to air quality from the No Action Alternative and the Preferred Alternative. 

7.5.1 NO ACTION ALTERNATIVE 

For purposes of analysis in this EIS, FRA assumed that with the No Action Alternative, the Project 

Sponsor would not build the Preferred Alternative. Under the No Action Alternative, existing 

activities in the rail yard (including train movements and ongoing general maintenance of the yard 

and LIRR facilities) would continue unchanged. Therefore, the No Action Alternative would not 

result in increased pollutant concentrations above existing levels and would not adversely affect 

air quality. 
Chapter 7: Air Quality, Greenhouse Gas Emissions, and Resilience

7-11 June 2021

7.5.2 OPERATIONAL IMPACTS OF THE PREFERRED ALTERNATIVE

Table 7-7 presents the maximum predicted concentrations associated with ventilation of dualmode locomotive engine exhaust. To estimate the maximum total pollutant concentrations, FRA 

added the modeled concentrations from the Preferred Alternative to a background value that 

accounts for existing pollutant concentrations from other nearby sources. 

Table 7-7 

Maximum Pollutant Concentrations from Platform Ventilation Systems

Pollutant

Averaging 

Period Units

Maximum 

Modeled Impact

Background

Concentration(1) Total Concentration NAAQS

NO2 1-hour μg/m3 N/A(2) N/A(2) 155.8 188

NO2 Annual μg/m3 2.1 37.9 40.0 100

CO 1-hour ppm 0.1 2.5 2.6 35(3)

CO 8-hour ppm < 0.1 1.2 1.2 9(3)

PM10 24-hour μg/m3 0.7 38 38.7 150

PM2.5 24-hour μg/m3 0.7 19.7 20.3 35

PM2.5 Annual μg/m3 0.08 9.0 9.08 15

Notes:

N/A—Not Applicable

(1) The background levels are based on the most representative concentrations monitored at NYSDEC 

ambient air monitoring stations. Due to the statistical form of the associated NAAQS background 

concentrations may differ from values in Table 7-4. (2) The 1-hour average NO2 concentration represents the maximum of the total 98th percentile 1-hour 

concentration predicted at any receptor using seasonal-hourly background concentrations. Modeling 

impacts are added to background concentrations for each hour within the AERMOD model. Therefore, 

the maximum modeled impact and background concentration are not shown.

As shown in Table 7-7, the maximum predicted total concentrations are below the applicable 

NAAQS. Furthermore, PM2.5 and CO incremental concentrations are below the City’s de minimis

criteria for these pollutants (see Table 7-8); therefore, FRA has predicted no adverse air quality 

impacts during operation of the Preferred Alternative.

Table 7-8 

Maximum Pollutant Incremental Concentrations 

from Platform Ventilation Systems 

Pollutant Averaging Period Units Maximum Modeled Impact CEQR De Minimis Criteria

CO 8-hour ppm < 0.1 4.7(1)

PM2.5 24-hour μg/m3 0.7 7.7(2)

PM2.5 Annual μg/m3 0.08 0.3(2)

Notes:

(1) While NEPA does not require projects under assessment to utilize impact criteria from the CEQR 

Technical Manual, the 8-hour average CO de minimis incremental concentration threshold is 

considered as one factor in determining whether the Preferred Alternative may result in environmental 

impacts. 

(2) While NEPA does not require projects under assessment to utilize impact criteria from the CEQR 

Technical Manual, the 24-hour and annual average PM2.5 de minimis incremental concentration 

thresholds are considered as one factor in determining whether the Preferred Alternative may result in 

environmental impacts.
June 2021 7-12

7.5.3 CONSTRUCTION IMPACTS OF THE PREFERRED ALTERNATIVE

Table 7-9 presents the maximum concentrations FRA predicted during the representative worstcase construction periods. To estimate the maximum total NO2, CO, and PM10 concentrations, 

FRA added the modeled concentrations from the Preferred Alternative to a background value that 

accounts for existing pollutant concentrations from other nearby sources. 

Table 7-9 

Maximum Pollutant Concentrations from Peak Construction Period 

Pollutant

Averaging 

Period Units

Maximum 

Modeled Impact

Background

Concentration(1)

Total 

Concentration NAAQS

NO2 Annual μg/m3 15.2 37.9 53.1 100

CO 1-hour ppm 0.3 2.5 2.8 35(2)

CO 8-hour ppm 0.1 1.2 1.3 9(2)

PM10 24-hour μg/m3 11 38 49 150

PM2.5 24-hour μg/m3 6.2 19.7 25.9 35

PM2.5 Annual—Local μg/m3 0.23 9.0 9.23 15

Notes:

N/A—Not Applicable

(1) The background levels are based on the most representative concentrations monitored at NYSDEC 

ambient air monitoring stations

As shown in Table 7-9, the maximum predicted total concentrations of NO2, CO, PM10, and PM2.5

are below the applicable NAAQS for the peak construction. In addition, PM2.5 and CO incremental 

concentrations are below the City’s de minimis criteria for these pollutants (see Table 7-10).

Emissions from the other less intensive construction periods would be less than the emissions 

during the modeled worst-case periods; therefore, the resulting concentrations from these nonpeak periods are expected to be less than the concentrations presented in Table 7-9 and Table

7-10. 

Table 7-10

Maximum Pollutant Incremental Concentrations 

from Peak Construction Period

Pollutant

Averaging 

Period Units

Maximum Modeled 

Impact CEQR De Minimis Criteria

CO 8-hour ppm 0.3 4.7(1)

PM2.5 24-hour μg/m3 6.2 7.7(2)

PM2.5 Annual μg/m3 0.23 0.3(2)

Notes:

(1) While NEPA does not require projects under assessment to utilize impact criteria from the CEQR 

Technical Manual, the 8-hour average CO de minimis incremental concentration threshold is 

considered as one factor in determining whether the Preferred Alternative may result in environmental 

impacts. 

(2) While NEPA does not require projects under assessment to utilize impact criteria from the CEQR 

Technical Manual, the 24-hour and annual average PM2.5 de minimis incremental concentration 

thresholds are considered as one factor in determining whether the Preferred Alternative may result in 

environmental impacts.
Chapter 7: Air Quality, Greenhouse Gas Emissions, and Resilience

7-13 June 2021

7.5.4 CONFORMITY WITH STATE IMPLEMENTATION PLAN

As discussed in Appendix D, the annual on-site and on-road construction-related emissions were 

estimated for the scheduled construction duration (2021 through 2026) and are presented in Table 

7-11. The values presented in the table are the total of direct and indirect emissions (including 

indirect emissions associated with construction truck and worker vehicle trips within the nonattainment area), consistent with General Conformity requirements. The pollutant emissions 

associated with construction under the Preferred Alternative would be well below any of the de 

minimis criteria. Therefore, the Preferred Alternative would conform to the SIP and does not 

require a full conformity determination.

Table 7-11

Mesoscale Emissions from Construction Activities (ton/yr)

PM2.5 PM10 NOx VOC SO2 CO

De Minimis Criteria 100 100 50 50 100 100

2021 0.02 0.04 0.39 0.09 <0.01 0.17

2022 0.32 0.69 5.89 1.28 0.04 6.15

2023 0.36* 0.81* 6.78* 1.52* 0.05* 7.47*

2024 0.26 0.64 5.03 1.22 0.04 6.03

2025 0.15 0.41 3.01 0.78 0.02 4.03

2026 0.04 0.12 0.90 0.30 0.01 2.01

Note: * Highest annual emissions

7.5.5 GREENHOUSE GAS EMISSIONS AND RESILIENCY

7.5.5.1 GREENHOUSE GAS EMISSIONS

The electricity use associated with the Platform’s ventilation systems, emission factors, and 

resulting GHG emissions associated with the Platform’s ventilation systems would result in 7,000 

metric tons of CO2e per year. FRA conservatively assumed an electricity emission factor that 

represents the latest data available for New York City and not the future build year. Both New York 

State and New York City have proposed policies to reduce GHG emissions associated with 

electrical power generation in future years with expanded utilization of renewable energy and the 

elimination of high emission fuels. Therefore, FRA expects GHG emissions from the Preferred 

Alternative to be lower in 2026 and future years. 

Table 7-12 presents the estimated GHG emissions FRA calculated from construction of the 

Preferred Alternative. The total emissions associated with construction throughout the construction 

period, including both direct energy and emissions embedded in materials (extraction, production, 

and transport), would be approximately 68 thousand metric tons CO2e.

Table 7-12

GHG Emissions from Construction (metric tons CO2e)

Total

Non-road Construction Equipment 16,115

On-Road Vehicles 29,645

Construction Materials:

Cement 

Steel

12,617

9,612

Total 67,990
June 2021 7-14

7.5.5.2 RESILIENCY 

Given the vulnerability of the Project Site, the Project Sponsor would construct the Platform at DBE 

of approximately +33 feet NAVD88 and would remain above the 1 percent annual chance BFE over 

the entire lifespan of the project under all sea level rise projections (see Table 7-5). While the 

Platform’s structural support system would extend through the floodplain, it would be designed for 

the wave, stream flow and other forces applied to the platform supporting elements by the potential 

flood event. The Tunnel Encasement would be constructed below grade, would be fully enclosed, 

and flood proofed. No other project elements included in the Preferred Alternative would be located 

below the elevation of the 1 percent annual chance BFE over the lifespan of the project.

In addition to the design for resilience, described below, the Project Sponsor designed the 

Preferred Alternative with redundancy by providing the new trans-Hudson connection into New 

York Penn Station as an additional resilient option once all construction is completed.

7.5.5.2.1 Coastal Flooding

Since the Preferred Alternative would not introduce any substantial changes in a coastal area such 

that it could affect wave impacts or otherwise affect flooding of other areas and uses, the Preferred 

Alternative would otherwise not affect or be affected by flooding. 

The Design Flood Elevation (DFE) for the Preferred Alternative is at least 21 feet higher than the 

current BFE at any given location, and would account for an additional 1 foot of “freeboard” over 

the BFE to cover uncertainty in the data and rounding. Therefore, additional protection is not 

anticipated to be needed. 

7.5.5.2.2 Temperature 

As described in Section 7.4.2.2.2, average annual temperature will continue to increase over time, 

and heatwaves (events with a duration of three or more days with maximum temperatures exceeding 

90oF) may quadruple in frequency, and double in duration (more heatwave events per year and 

longer events). The effect of high temperature on the Preferred Alternative would include increased 

energy use for Platform ventilation and train air conditioning, but since the design for these needs is 

conservative, no special consideration needs to be given to capacities of those systems. 
Chapter 7: Air Quality, Greenhouse Gas Emissions, and Resilience

7-15 June 2021

High temperatures have also been known to affect railway tracks if buckling (rail deformation) 

occurs. In general, track buckling occurs predominately on continuously welded rail, though it also 

can occur on older jointed track when the ends of the track become frozen in place.12

12 European Commission. Impacts of Climate Change on Transport: A Focus on Road and Rail Transport 

Infrastructures. Available: http://ftp.jrc.es/EURdoc/JRC72217.pdf. 2012. 

,13

13 FEMA. Flood Insurance Rate Map, New York County, New York—Preliminary. Panel 69 of 457. Map 

3604970069G. December 5, 2013.

Track 

buckling is most prevalent on an isolated hot day in the springtime or early summer, rather than 

mid to late summer when temperatures are more uniformly hot. Buckling also is more likely to 

occur in alternating sun/shade regions and in curves. Track design generally accounts for track 

buckling via design criteria and prevents buckling even at rail temperatures of up to 150oF.14

14 FHWA. U.S. Climate Change Science Program Synthesis and Assessment Product 4.7: Impacts of Climate 

Change and Variability on Transportation Systems and Infrastructure: Gulf Coast Study, Phase I. March 2008. 

The 

design would also accommodate changes in length of segments due to thermal movement, such 

as would occur during a heatwave. Since the track is more stable when the rail is in tension at 

temperatures below the neutral temperature, the target neutral temperature is generally 75 percent 

of the expected maximum temperature of the region. An increase in temperature may slightly raise 

the neutral temperature used for installation, but is unlikely to necessitate track design changes. 

The Project Sponsor has included a new ventilation system for the covered rail yard, which 

complies with LIRR requirements that would be used to vent hot air from the rail yard when 

temperatures exceed specified levels to help avoid conditions that could lead to rail deformation.

Preventive measures to reduce rail buckling derailment risk include:

• Improving weather forecast and predictive capacity for rail track temperature;

• Utilizing track materials that can withstand projected temperatures (such as concrete ties, 

continuous welded rail, and rail fasteners); and

• Applying speed limit restrictions during periods of high temperatures.

Overall, appropriate design, maintenance, and operational procedures for track buckling in the 

current condition would also address the future condition when heatwaves may be more frequent 

or intense.

7.5.5.2.3 Precipitation

As described in Section 7.4.2.2.3, NPCC projected that annual average precipitation is likely to 

increase and the number of downpours (intense precipitation events shorter than a day and often 

shorter than 1 hour) is “very likely” to increase. Shorter term downpour intensity is also projected 

to increase. In addition to coastal flood conditions discussed above, stormwater facilities would be 

designed to accommodate runoff based on short-term precipitation events, including 10- or 20-

percent annual probability (“10-year” and “5-year”) events for New York City and New Jersey/New 

York State roadway and parking lot storm systems, respectively, 4-percent annual probability (“25-

year”) events for track roadbed and for drains at low points that could flood roadways or track 

roadbed, and 1-percent annual probability (“100-year”) events for enclosed structures that could 

flood roadways or track roadbed. The projected increase in short-term precipitation intensity, 

presented in Table 7-6 above, would be accounted for where relevant and practicable for drainage 

and runoff design purposes. 
June 2021 7-16

7.5.5.2.4 Construction 

During construction, the existing Western Rail Yard would continue to be at risk of severe storm 

flooding at the current levels. As part of the design of the Preferred Alternative, the Project Sponsor

would be responsible to develop a stormwater management plan and identify measures to address 

risk. At a minimum, the plan would identify the potential risks during the construction period and 

would prepare for potential storms and/or flooding up to the levels identified. These requirements 

would be included in the contract documents between the Project Sponsor and the Project 

Sponsor’s Contractor, and the Contractor would be responsible for implementing the stormwater

management plan.

Changes in temperature and precipitation climate in the short term, throughout the construction 

period, would be very small and would have no measurable impact on construction operations.

7.6 AVOIDANCE, MINIMIZATION, AND MITIGATION 

MEASURES

• The Project Sponsor would undertake measures to reduce both criteria pollutant and GHG 

emissions during construction in accordance with all applicable laws, regulations, and building 

codes. In addition, the Preferred Alternative would include the implementation of an emissions 

reduction program to minimize the air quality effects from construction. 

• In conformance with the Emission Reduction Program included in the CEPP (as described in 

detail in Chapter 22, “Mitigation Measures and Project Commitments”), the Project Sponsor 

would include contract specifications requiring the use of the following BMPs:

- Clean Fuel. Only ULSD fuel would be used for all diesel engines throughout the 

construction site.

- Diesel Equipment Reduction. Electrically powered equipment such as welders and saws

would be used instead of diesel-powered versions of that equipment, to the extent feasible 

and practicable. 

- Dust Control Measures. Contract specifications would require a dust control plan, 

including a watering program, to minimize dust emissions from construction activities. For 

example, all trucks hauling loose material would be equipped with tight-fitting tailgates and 

their loads securely covered prior to leaving the Project Site and water sprays would be 

used for all demolition, excavation, and transfer of soils to ensure that materials would be 

dampened as necessary to avoid the suspension of dust into the air. 

- Idling Restriction. As required by local law, all stationary vehicles on roadways adjacent 

to the Project Site would be prohibited from idling for more than three minutes. The idling 

restriction excludes vehicles that are using their engines to operate a loading, unloading, 

or processing device (e.g., concrete-mixing trucks) or otherwise required for the proper 

operation of the engine. 

- Engine Retrofits. Non-road diesel engines with a power rating of 50 horsepower (hp) or 

greater and controlled truck fleets (i.e., truck fleets under long-term contract with the 

Preferred Alternative), including but not limited to, concrete mixing and pumping trucks 

would utilize the best available technology (BAT) (e.g., diesel particulate filters) for 

reducing diesel particulate matter emissions. 
Chapter 7: Air Quality, Greenhouse Gas Emissions, and Resilience

7-17 June 2021

- Utilization of Newer Equipment. USEPA’s Tier 1 through 4 standards for non-road engines 

regulate the emission of criteria pollutants from new engines, including PM, CO, NOx, and 

hydrocarbons (HC). All diesel-powered non-road construction equipment with a power 

rating of 50 hp or greater would meet at least the Tier 3 emissions standard.15

15 The first federal regulations for new non-road diesel engines were adopted in 1994 and signed by USEPA into 

regulation in a 1998 Final Rulemaking. The 1998 regulation introduces Tier 1 emissions standards for all 

equipment 50 hp and greater and phases in the increasingly stringent Tier 2 and Tier 3 standards for equipment 

manufactured in 2000 through 2008. In 2004, the USEPA introduced Tier 4 emissions standards with a phasedin period of 2008 to 2015. The Tier 1 through 4 standards regulate the USEPA criteria pollutants, including PM, 

HC, NOx and CO. Prior to 1998, emissions from non-road diesel engines were unregulated. These engines are 

typically referred to as Tier 0. 

 

• The Project Sponsor would develop a stormwater management plan and identify measures to 

address risk from potential flooding due to precipitation, as discussed above in Section 7.5.2.3, 

“Precipitation.”

FRA has accounted for the implementation of the emissions reduction measures listed above in 

the analysis of construction air quality impacts under the Preferred Alternative. The Preferred 

Alternative would include a new ventilation system with several fan plants which would be 

designed to ventilate daily emissions and emergency smoke events to maintain air quality under 

operational conditions. The new ventilation system would be designed in compliance with all 

applicable laws, regulations, and building codes to ensure no adverse air quality effects from 

operation of these systems.

• The Project Sponsor would be responsible for implementing these BMPs. With the 

implementation of those measures, no adverse construction or operational air quality impacts 

would result from the Preferred Alternative and no mitigation is required. 