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APPENDIX A4
AIR QUALITY TECHNICAL MEMORANDUM
FOR THE
State Highway 9 Iron Springs Alignment
Environmental Assessment
Prepared for
COLORADO DEPARTMENT OF TRANSPORTATION
FEDERAL HIGHWAY ADMINISTRATION
Prepared by
JILL SCHLAEFER
COLORADO DEPARTMENT OF TRANSPORTATION
ENVIRONMENTAL PROGRAM BRANCH
April 2014
Air Quality for the State Highway 9 Iron Springs Alignment EA
April 2014 i
CONTENTS
Introduction .................................................................................................................. 1
Proposed Action .............................................................................................................. 1
No Action Alternative ..................................................................................................... 1
Air Quality Assessment ................................................................................................. 4
Criteria Pollutants ........................................................................................................... 4
Mobile Source Air Toxics ................................................................................................. 4
Fugitive Dust ................................................................................................................... 4
Greenhouse Gases .......................................................................................................... 4
Construction Impacts ...................................................................................................... 6
Mitigation ........................................................................................................................ 7
References .................................................................................................................... 7
TABLES
Table 1 Carbon Dioxide (CO2) Emissions Data .......................................................................... 6
FIGURES
Figure 1 Proposed Action ........................................................................................................... 2
Figure 2 No Action Alternative (Previously Approved) .............................................................. 3
Air Quality for the State Highway 9 Iron Springs Alignment EA
April 2014 ii
ACRONYMS
CDOT Colorado Department of Transportation CO2 Carbon Dioxide EA Environmental Assessment EIS Environmental Impact Statement EPA Environmental Protection Agency FHWA Federal Highway Administration GHG Greenhouse Gas MMT Million Metric Tons MSAT Mobile Source Air Toxics NAAQS National Ambient Air Quality Standards PM2.5 Particulate Matter smaller than 2.5 microns PM10 Particulate Matter smaller than 10 microns ROD Record of Decision SH 9 State Highway 9 VMT vehicle miles traveled
Air Quality for the State Highway 9 Iron Springs Alignment EA
April 2014 1
INTRODUCTION 1
This technical memorandum has been prepared in support of the State Highway (SH) 9 Iron 2
Springs Alignment Environmental Assessment (EA). This technical memorandum evaluates the 3
effects of the Iron Springs Alignment (Proposed Action) and the No Action Alternative (widening 4
on the existing alignment) with respect to air quality. 5
Proposed Action 6
As part of implementation of the SH 9 improvements between Frisco and Breckenridge, the Colorado 7
Department of Transportation (CDOT) and Federal Highway Administration (FHWA) are proposing to 8
realign approximately 1.3 miles of existing SH 9 just south of the Town of Frisco, Colorado (see 9
Figure 1). This stretch of SH 9, which falls between mileposts 93 and 95, would be realigned to 10
provide a four‐lane reduced section roadway away from Dillon Reservoir. This Proposed Action 11
would shorten SH 9 by approximately 0.4 mile. The Proposed Action would provide roadway safety 12
benefits, as well as water quality and drinking water protection benefits, as a result of straightening 13
the highway to remove a tight, compound curve (known as Leslie’s Curve), which is in close proximity 14
to Dillon Reservoir. The existing condition on Leslie’s Curve is considered substandard and 15
contributes to accidents in the area. 16
The Proposed Action would include realignment of a portion of the existing Frisco‐Farmer’s 17
Korner‐Blue River Bikeway (also referred to herein for brevity as the Blue River Bikeway or 18
bikeway). This portion of the bikeway would be moved to the alignment currently occupied by 19
SH 9, would be approximately 0.4 mile longer than the existing bikeway, and would be at a 20
gentler grade than the current alignment. In addition, the Dickey Day Use Parking Lot would be 21
moved west to a new parking lot to be constructed as part of the project, with access provided 22
via Recreation Way using the existing signalized intersection at SH 9 and Recreation Way. A new 23
trail connection would be provided to link the proposed parking lot with the realigned bikeway 24
and existing trail, which currently begins at the old Dickey Day Use Parking Lot. 25
Additional detail regarding the Proposed Action, including typical sections, is provided in the EA 26
main text and the project drawings provided in Appendix A1 of the EA. 27
No Action Alternative 28
If the Proposed Action is not selected for implementation, SH 9 would be widened to provide a 29
four‐lane reduced section roadway along the existing alignment as previously approved in the 30
SH 9 Frisco to Breckenridge Environmental Impact Statement (EIS) and Record of Decision (ROD) 31
(CDOT and FHWA, 2004a; 2004b) (Figure 2). The 2004 Preferred Alternative is considered the 32
“No Action Alternative” for this EA and is used as a baseline for comparison with the Proposed 33
Action. These improvements would be implemented if the Proposed Action is not selected. 34
Widening along the existing alignment would require large rock cuts and retaining walls 35
(problematic to design and construct), and the highway would remain in close proximity to 36
Dillon Reservoir. The length of SH 9 would remain the same as the existing highway. The tight 37
Leslie’s Curve would not be eliminated; however, safety features such as a barrier between 38
opposing lanes would be installed to improve safety. 39
With this alternative, approximately 0.8 mile of the existing Blue River Bikeway would be 40
realigned to allow space for the highway widening. The length of bikeway would not change 41
appreciably and the current relatively steep grades on the path would remain. 42
Additional detail regarding the No Action Alternative, including typical sections, is provided in 43
the EA main text and the project drawings provided in Appendix A1 of the EA. 44
Air Quality for the State Highway 9 Iron Springs Alignment EA
April 2014 2
Figure 1 Proposed Action 1
2
3
Air Quality for the State Highway 9 Iron Springs Alignment EA
April 2014 3
Figure 2 No Action Alternative (Previously Approved) 1
2
3
Air Quality for the State Highway 9 Iron Springs Alignment EA
April 2014 4
AIR QUALITY ASSESSMENT 1
Criteria Pollutants 2
Summit County is in attainment for all criteria pollutants identified and monitored by 3
Environmental Protection Agency (EPA) as important sources of human and environmental 4
health concern when they occur in ambient concentrations above the National Ambient Air 5
Quality Standards (NAAQS). These pollutants include carbon monoxide, particulate matter 6
smaller than 10 microns (PM10) and 2.5 microns (PM2.5), nitrogen dioxide, sulfur dioxide, lead, 7
and ground level ozone. Only PM10 is currently monitored near the project area. Although 8
isolated PM10 events exceeded the 150 µg/m3 (microgram per cubic meter) 24‐hour threshold 9
concentration in 2000 and 2005, no NAAQS violations have occurred in the past 20 years 10
(exceedances averaged over three years must be less than one). Because the Proposed Action 11
will shorten the overall highway length and better moderate traffic flow, fewer emissions will be 12
generated when compared to the No Action Alternative, thus criteria pollutant concentrations 13
are expected to remain below the NAAQS. 14
Mobile Source Air Toxics 15
The purpose of the project remains the same—as identified for the SH 9 corridor as a whole in 16
the previous EIS and ROD (CDOT and FHWA, 2004a; 2004b)—to improve transportation along 17
SH 9 by decreasing travel time, improving safety, and supporting the transportation needs of 18
local and regional travelers while minimizing impacts to the surrounding environment and 19
communities. This evaluation has been determined to generate minimal air quality impacts for 20
Clean Air Act Amendment criteria pollutants and has not been linked with any special Mobile 21
Source Air Toxics (MSAT) concerns. As such, this project will not result in changes in traffic 22
volumes, vehicle mix, or any other factor that would cause an increase in MSAT project impacts. 23
Moreover, EPA regulations for vehicle engines and fuels will cause overall MSAT emissions to 24
decline significantly over the next several decades. Based on regulations now in effect, an 25
analysis of national trends with EPA's MOVES2010b model forecasts a combined reduction of 26
83 percent in the total annual emission rate for the priority MSAT from 2010 to 2050 while 27
vehicle‐miles of travel are projected to increase by 102 percent. This will reduce the background 28
level of MSAT and the possibility of even minor MSAT emissions from this project. 29
Fugitive Dust 30
The length of roadway under the Proposed Action will be shorter than that under the No Action 31
Alternative by approximately 0.4 mile; corresponding to an estimated 7.2 tons per year less of 32
fugitive dust (PM10) from excess road sand re‐entrainment. Re‐entrainment is the process by 33
which surface sediment (in this case, sand) is incorporated into a fluvial flow (in this case, air) as 34
part of the process of erosion. Regular post‐storm street sweeping will reduce this annual 35
amount by an estimated 1.1 tons. 36
Greenhouse Gases 37
The issue of global climate change is an important national and global concern that is being 38
addressed in several ways by the Federal government. The transportation sector is the second 39
largest source of total greenhouse gases (GHGs) in the United States, and the greatest source of 40
carbon dioxide (CO2) emissions – the predominant GHG. In 2004, the transportation sector was 41
responsible for 31 percent of all U.S. CO2 emissions. The principal anthropogenic (human made) 42
source of carbon emissions is the combustion of fossil fuels, which account for approximately 43
80 percent of anthropogenic emissions worldwide. Almost all of the transportation‐sector 44
Air Quality for the State Highway 9 Iron Springs Alignment EA
April 2014 5
emissions (98 percent) result from the consumption of petroleum products, such as gasoline, 1
diesel fuel, and aviation fuel. 2
Recognizing this concern, FHWA is working nationally with other modal administrations through 3
the U.S. Department of Transportation Center for Climate Change and Environmental 4
Forecasting to develop strategies to reduce transportation's contribution to GHGs—particularly 5
CO2 emissions—and to assess the risks to transportation systems and services from climate 6
changes. 7
At the state level, several programs are underway in Colorado to address transportation GHGs. 8
The Governor’s Climate Action Plan, adopted in November 2007, includes measures to adopt 9
vehicle CO2 emissions standards and to reduce vehicle travel through transit, flex time, 10
telecommuting, ridesharing, and broadband communications. CDOT issued a Policy Directive on 11
Air Quality in May 2009. This Policy Directive was developed with input from a number of 12
agencies, including the State of Colorado's Department of Public Health and Environment, EPA, 13
FHWA, the Federal Transit Administration, the Denver Regional Transportation District, and the 14
Denver Regional Air Quality Council. This Policy Directive addresses unregulated MSATs and 15
GHGs produced from Colorado’s state highways, interstates, and construction activities. 16
As a part of CDOT’s commitment to addressing MSATs and GHGs, some of CDOT’s program‐wide 17
activities include: 18
Developing truck routes/restrictions with the goal of limiting truck traffic in proximity to 19
facilities, including schools, with sensitive receptor populations. 20
Continuing to research pavement durability opportunities with the goal of reducing the 21
frequency of resurfacing and/or reconstruction projects. 22
Developing air quality educational materials, specific to transportation issues, for citizens, 23
elected officials, and schools. 24
Offering outreach to communities to integrate land use and transportation decisions to 25
reduce growth in vehicle miles traveled (VMT), such as smart growth techniques, buffer 26
zones, transit‐oriented development, walkable communities, access management plans, etc. 27
Committing to research additional concrete additives that would reduce the demand for 28
cement. 29
Expanding Transportation Demand Management efforts statewide to better use the existing 30
transportation mobility network. 31
Continuing to diversify the CDOT fleet by retrofitting diesel vehicles, specifying the types of 32
vehicles and equipment contractors may use, purchasing low‐emission vehicles, such as 33
hybrids, and purchasing cleaner burning fuels through bidding incentives where feasible. 34
Incentivizing is the likely vehicle for this. 35
Exploring congestion and/or right‐lane only restrictions for motor carriers. 36
Funding truck parking electrification (note: mostly via exploring external grant 37
opportunities). 38
Researching additional ways to improve freight movement and efficiency statewide. 39
Committing to incorporate ultra‐low sulfur diesel for non‐road equipment statewide. 40
Developing a low‐volatile organic compounds emitting tree landscaping specification. 41
Air Quality for the State Highway 9 Iron Springs Alignment EA
April 2014 6
Because climate change is a global issue, and the emissions changes due to project alternatives 1
are very small compared to global totals, the GHG emissions associated with the alternatives 2
were not calculated. Because GHGs are directly related to energy use, the changes in 3
GHG emissions would be similar to the changes in energy consumption presented in the EA. 4
Table 1 presents the relationship of current and projected Colorado highway emissions to total 5
global CO2 emissions. Colorado highway emissions are expected to increase by 4.7 percent 6
between now and 2035. The benefits of the fuel economy and renewable fuels programs in the 7
2007 Energy Bill are offset by growth in VMT; the draft 2035 statewide transportation plan 8
predicts that Colorado VMT will double between 2000 and 2035. Table 1 also illustrates the 9
relatively small size of the project corridor compared to total Colorado travel activity. 10
Table 1 Carbon Dioxide (CO2) Emissions Data 11
Global CO2 Emissions, 2005, in Million Metric Tons (MMT)1
Colorado Highway CO2 Emissions, 2005, in MMT1
Projected Colorado 2035 Highway CO2 Emissions, in MMT1
Colorado Highway Emissions, Percent of Global Total (2005)1
Project Corridor Vehicle Miles Traveled (VMT), Percent of Statewide VMT (2005)
27,700 29.9 31.3 0.108 <0.0001
1 Data provided by FHWA Resource Center
Construction Impacts 12
The overall construction project has the potential to last many months. Construction activities 13
may be sources of temporary air quality impacts from fugitive dust or equipment emissions. 14
Adjoining properties in the study area would be near construction activities when the proposed 15
project is built. Construction emissions differ from regular traffic emissions in several ways: 16
Construction emissions last only for the duration of the construction period. 17
Construction activities generally are short term, and depending on the nature of the 18
construction operations, could last from seconds (for example, a truck passing) to 19
months (for example, constructing a bridge). 20
Construction can involve other emission sources, such as fugitive dust from ground 21
disturbance. 22
Construction emissions tend to be intermittent and depend on the type of operation, 23
location, and function of the equipment, and the equipment usage cycle; traffic 24
emissions are present in a more continuous fashion after construction activities are 25
completed. 26
Construction emissions tend to be from mobile sources with diesel engines. 27
Construction emission impacts will be minimized somewhat because most of the project 28
improvements do not abut sensitive areas such as residences. Even so, people in neighboring 29
areas could be exposed to construction‐related emissions. The Proposed Action and the No 30
Action Alternative would be similar in nature to other highway projects and the construction 31
emissions should be representative of projects of this type and magnitude. These types of 32
projects generally do not cause meaningful air quality impacts. 33
Air Quality for the State Highway 9 Iron Springs Alignment EA
April 2014 7
Mitigation 1
Standard emission minimization measures for construction activities are recommended. 2
Construction emission impacts will be minimized somewhat because the Proposed Action and 3
the No Action Alternative are located away from sensitive areas such as residences. Even so, 4
neighboring areas could be exposed to construction‐related emissions and particular attention 5
will be given to minimizing total emissions near sensitive areas such as homes. To address the 6
temporary elevated air emissions that may be experienced during construction, standard 7
construction mitigation measures shall be incorporated into construction contracts where 8
feasible. These include following best management practices and relevant CDOT construction 9
specifications. These will include: 10
Maintain equipment on a regular basis. Equipment will be subject to inspection by the 11
project manager to ensure maintenance. 12
Systematically control fugitive dust through the diligent implementation of CDOT’s 13
Standard Specifications for Road and Bridge Construction, particularly Sections 107.24, 14
209 and 250, and Air Pollution Control Division’s Air Pollutant Emission Notification 15
requirements. 16
Allow no excessive idling of inactive equipment or vehicles. 17
Other emission reduction actions may include: 18
Locate stationary equipment as far from sensitive receivers as possible (when conditions 19
allow) 20
Implement stricter dust control measures near schools during school hours 21
Retrofit older construction vehicles to reduce emissions 22
REFERENCES 23
Colorado Department of Transportation (CDOT) and Federal Highway Administration (FHWA). 24
2004a. State Highway 9 Frisco to Breckenridge Final Environmental Impact Statement and 4(f) 25
Evaluation. February. [Note: This document is an abbreviated Final EIS which incorporates the 26
Draft EIS, constituting the complete Final EIS.] 27
Colorado Department of Transportation (CDOT) and Federal Highway Administration (FHWA). 28
2004b. State Highway 9 Frisco to Breckenridge Record of Decision. May. 29