jj\	CLEANUP - CLEAN AIR
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KOl1
y	DIESEL EMISSIONS & GREENHOUSE GAS REDUCTIONS

The goal of Cleanup—Clean Air is to
encourage, facilitate, and support diesei
emissions and greenhouse gas reductions
technologies and practices at Superfund
cleanup and redevelopment sites.

Clean	Diesel
Technologies
Alternative
Superfund
•	Diesel Emissions Health Effects • Costs
•	Technology and Fuel Basics	• Funding Resources
Clean Diesel Technologies and
Alternative Fuels
Clean diesei technologies include newer engines and
retrofit devices that significantly reduce harmful
pollutants, especially particulate matter (PM) and
nitrogen oxides (NOx). While new engines will soon be
mandated to be constructed with advanced emission
control technologies, older engines run cleaner after
retrofitting, replacement, or using cleaner fuels. The
two most widely used retrofit technologies are diesei
particulate filters (DPFs) and diesei oxidation catalysts
(DOCs). Also, cleaner fuels, like ultra-low-sulfur diesei,
(ULSD) and alternative fuels, such as biodiesel, emit
lower emissions compared to conventional diesei.
Purpose of Cleanup—Clean Air
The Cleanup-Clean Air Initiative (CCA) is focused on
encouraging, facilitating and supporting implementation
of diesei emissions and greenhouse gas reductions
technologies and practices at Superfund cleanup and
redevelopment sites. To accomplish the diesei
emissions reductions goal, Cleanup - Clean Air:
Raises awareness of the potential for diesei
emissions reductions from heavy duty vehicles and
equipment used at Superfund cleanup and
redevelopment sites;
Provides coordination and facilitation support for
potential Cleanup-Clean Air projects;
Creates a forum for information sharing among
diesei emissions reductions advocates, and works
to leverage significant new resources to expand
voluntary diesei emissions mitigation efforts; and
Creates momentum for future diesei emission
reduction efforts within the Superfund Program and
elsewhere.
Importance of Reducing Diesel
Emissions
Reducing emissions from diesei engines is one of the
most important air quality challenges facing the country.
Diesel engines emit a complex mixture of air pollutants
including both solid and gaseous materials that have
serious human and environmental impacts. The EPA
has deemed diesei exhaust as a "likely human
carcinogen."1 The State of California has classified
over 40 diesei exhaust pollutants as "toxic air
contaminants."2 Diesel pollution is of concern for site
workers and surrounding communities. The pollutants
that cause the most concern are particulate matter and
nitrogen oxides.
Particulate matter (PM):
PM is the general term for a mixture of solid particles
and liquid droplets found in the air.3 Diesel engines
emit particles smaller than 10 micrometers (|j,m) in
diameter and nearly all are under 2.5 |j,m. Human
exposure to PM2.s is especially dangerous because
these particles can penetrate deep into the lungs and
cause serious problems including asthma, heart
attacks, and even premature death.4
Hair cross section (70 |xm)
Size of diesei particulate matter compared with hair cross section.
Image courtesy U.S. EPA West Coast Diesel Collaborative
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CLEANUP - CLEAN AIR
. EMISSIONS & GREENHOUSE GAS REDUCTIONS
Human arid Environmental Health Risks from Diesel Pollutants6
Particulate Matter (PM)
Nitrogen Oxides (NCM
0
IRRITATION OF AIRWAYS
0
ACID RAIN
0
COUGHING
0
CLIMATE CHANGE
0
DIFFICULTY BREATHING
0
WATER QUALITY DETERIORATION
0
AGGRAVATED ASTHMA
0
VISIBILITY IMPAIRMENTS
0
DECREASED LUNG FUNCTION
0
SMOG/PRECURSOR TO GROUND-LEVEL OZONE
0
LUNG AND HEART DISEASE
0
FORMATION OF TOXIC CHEMICALS
0
ACUTE AND CHRONIC BRONCHITIS
0
ASTHMA IN CHILDREN
0
IRREGULAR HEARTBEAT
0
INCREASES LUNG SUSCEPTIBILITY TO TOXINS
0
HEART ATTACKS

AND MICROORGANISMS
in 2002, U.S. off-road diesel construction
vehicles emitted about 764,000 tons of
NOx into our air.7
Nitrogen Oxides (NOx):
NOx is the term for a group of highly reactive gases that
contain nitrogen and oxygen in varying amounts. NOx
form when fuel Is burned at high temperatures, such as
in a diesel engine. NQX emissions contribute to human
health and environmental problems.
Carbon Monoxide (CO) and Sulfur Oxides (SOx):
These pollutants are present in lower amounts in diesel
exhaust but may also pose a risk to human health. CO
can cause fatigue in healthy people and chest pain in
people with heart disease. Exposure to moderate
concentrations may cause angina, impaired vision, and
reduced brain
function. Higher
concentrations can
cause headaches,
dizziness,
confusion, nausea,
and can even be
fatal. SOx can
cause breathing
problems for people
with asthma. SOx
can also aggravate heart disease and induce
respiratory illness and is a major component of ambient
PM. In addition, this pollutant is a major component in
acid rain formation, which harms ecosystems and
degrades buildings and statues.
Front loader retrofitted with DPF.
Image courtesy U.S. EPA8
Nationwide PM
•	In 2002, roughly 71,000 tons of PM10 were emitted
from diesel construction equipment. About 95% of it
w as PM 2.5.9
•	PM causes about 15,000 premature deaths a year
(comparable to the number of deaths from 2nd hand
smoke and traffic accidents in California).10
•	Diesel emissions result in approximately 6,000
children's asthma-related emergency room visits
every year.11
•	PM causes about 15,000 heart attacks per year.12
Approaches to Reduce Diesel
Emissions
RETROFIT engines with EPA or California Air Resources
Board verified diesel emission control technologies.
MAINTAIN in accordance with engine manual (e.g.,
change air filters, check engine timing, fuel injectors
and pumps) and keep engines well tuned.
REFUEL with biodiesel, other alternative fuels, or with
cleaner fuels such as ultra-low-sulfur diesel (ULSD).
MODIFY OPERATIONS by reducing operating and idle
time.
REPLACE existing engines with new cleaner diesel
engines, hybrid engines, or engines compatible with
alternative fuels.
According to a Union of Concerned Scientists
report, in California alone, diesel PM
contributes to $21.5 billion per year in
healthcare related costs.1'
Cleanup - Clean Air
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Emission Control Technologies
Engines can be retrofitted with many kinds of emissions control devices. This chart provides information
on those that are most widely used. For a list of verified diesel emissions control technologies, go to:
www.epa.qov/otaq/retrofit/verif-list.htm and www.arb.ca.qov/diesel/verdev/vt/cvt.htm.
CLEANUP - CLEAN AIR
DIESEL EMISSIONS & GREENHOUSE GAS REDUCTIONS

Diesel Particulate Filter
(DPF)
Diesel Oxidation Catalyst
(DOC)
Selective Catalytic Reduction
(SCR)
Technology
Description
Wall-flow type filter installed in the
exhaust system, much like a muffler, in
which PM emissions are trapped. Active
DPFs require regular maintenance to
regenerate or burn off accumulated PM,
when the engine is not in use. Passive
DPFs regenerate during engine
operation if exhaust temperature
requirements are met. (see image on
page 2)
Canister-like device containing a
honeycomb structure that is
installed in the exhaust system. A
catalyst oxidizes CO and
hydrocarbons as the exhaust
flows through, which breaks them
down into less harmful
components.
Device that injects urea, or
some form of ammonia, into
the exhaust stream and reacts
over a catalyst to reduce NOx
emissions.
Cost per
retrofit varies
with engine
size
$7,000-$10,00014
$500-$2,00015
$12,000 with DOC
$20,000 with DPF16
Emissions
Reductions
•	PM reduced 60%-90%
•	Hydrocarbons (HC) reduced 60%-90%
•	Carbon monoxide reduced 60%-90%
•	PM reduced 40%-50%18
•	HC reduced 50%
•	CO reduced 50%
SCR without DOC or DPF
•	PM reduced 25%
•	NOx reduced 80%
•	HC reduced 80%
Benefits
•	Can be coupled with an exhaust gas
recirculation system to further reduce
NOx (up to 40%) and PM (up to 85%)
(MECA) though may not be
compatible with currently verified
DPFs17
•	Can also be coupled with a SCR to
reduce NOx and PM
•	Should not effect fuel economy,
shorten engine life nor
adversely affect drivability
•	Less restrictive than DPF
because DOCs are less
affected by exhaust loading
•	Works well with older, higher
emitting engines
•	Use of ULSD increases
efficiency
•	Commonly used in
stationary applications.
•	Often used with a DOC or
catalyzed DPF to achieve
greater PM reductions
Considerations
•	Annual maintenance costs
approximately $150-$31019
•	Active DPFs require maintenance to
keep filters clean. Passive DPFs
oxidize PM via catalysts or high
exhaust temperatures
•	Off-road applications may require
active DPFs
•	Diesel equipment needs to meet
minimum temperature requirements
specific to individual filter technologies
•	Slight fuel economy penalty from
pressure buildup in the exhaust
system; pressure and temperature
monitors are necessary
•	Requires ultra-low-sulfur diesel
•	1995 and older engines may overload
passive filters but may be compatible
with active regeneration systems
•	May suffer thermal degradation
when exposed to temperatures
above 650 C for prolonged
periods of time but these are
unlikely conditions during
normal operation
•	Requires normal exhaust
maintenance
•	Requires periodic refilling of
an ammonia or urea tank
•	Requires low-sulfur diesel
(500 ppm sulfur) or ULSD
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CLEANUP - CLEAN AIR
DIESEL EMISSIONS & GREENHOUSE GAS REDUCTIONS
to_JRetrofittinc|_a_Fleet_
Step 1 Inventory the fleet for each
engine and determine:
Type of equipment (backhoe, loader, etc.)
Engine model year, make, model,
horsepower, displacement
Engine family name
If a diesel emissions reduction device is
already in place. New engines may
have one installed.
IMPORTANT ENGINE INFORMATION
2000 THIS ENGINE CONFORMS TO U.S. EPA AND CALIFORNIA
50S	REGULATIONS APPLICABLE TO 2000 MODEL YEAR NEW HEAVY DUTY
DIESEL CYCLE ENGINES. THIS ENGINE HAS A PRIMARY INTENDED
SERVICE APPLICATIONAS A HEAVY DUTY ENGINE.
FUEL RATE AT ADV. HP 205. 6 MM3 / STROKE ADV. HP 500 AT 2100 RPM
INITIAL INJECTION TIMING U DEG. BTC	DISP. 12 . 7 LITERS
ENGINE FAMILY YDDXH12.7EGL	MIN. IDLE 600 RPM
MODbL SERIES GO, 12.7L	MFG. DATE FEB 2000
UNIT 06R0577657	CONFORMS TO AUSTRALIAN DESIGN RULE 30
Turbocharged or naturally aspirated
Mechanically or electrically controlled
If it employs exhaust gas recirculation
Step 2 Visit the EPA and CA Air Resources Board (CARB)
verification websites to determine compatible retrofit devices.
Step 3 Work with vendors to assess the compatibility of your
diesel equipment with a retrofit. They may need additional
information such as: location for mounting retrofit device (on the
muffler or on the side of the vehicle), size of the exhaust system,
and if there will be any changes to the exhaust system (sometimes
the retrofit device does not replace the muffler).
Step 4 Typically, datalogging is required before installing DPFs to
determine if the exhaust temperatures are sufficient for passive
DPF systems. Passive filters require high exhaust temperatures to
burn off the accumulated soot on the filter. Vendors will datalog
temperature information for a few days on each engine to see if
required temperature minimums are met. Datalogging
may cost about $200-$300 for 2-3 days of monitoring.21
Active DPF systems do not require high exhaust
temperatures but do require maintenance.
Equipment retrofitted with DPFs should always include a
device to monitor the increased pressure buildup in the
exhaust system. These devices, called back-pressure
monitoring systems, may also be installed with DOCs. A
warning light in the cab will notify the equipment operator if
back-pressure is too high and maintenance is necessary.
Retrofit installation may take place on-site or at the
dealership, depending on the contract with the dealer.
It is generally not recommended to remove a retrofit
device from an engine for which it was designed and use
it on another engine. Though this is possible if the
Example of engine emissions label where the family name can be found
Exhaust Gas Recirculation (EGR)
Engine combustion chambers can
reach temperatures greater than 2500ฐ
F. At these temperatures, nitrogen and
oxygen react to form nitrogen oxides
that contribute to smog. An EGR
device is used to lower NOx formation.
A valve recirculates exhaust into the air
intake stream. These gases displace
some of the normal intake, lowering
the peak temperature of the
combustion process by hundreds of
degrees and reduce the amount of
oxygen available to form NOx.20
However, an EGR system increases
PM emissions and are not compatible
with many verified retrofit technologies.
Engine Family Name
The Engine Family Name is a 12 digit
alphanumerical code designated to engines by
the EPA. It identifies engines by make, year,
displacement, and emissions characteristics. It is
important to get the Engine Family Name for each
engine as well as individual pieces of information
to facilitate the process of finding the appropriate
retrofit device. EPA and CARB verify retrofit
technologies for certain engines and other
requirements (such as minimum engine
temperature). This code can be found on a
sticker on the engine itself (see image above). If
the Engine Family Name cannot be found, retrofit
dealers may be able to determine it from the
other engine information provided. Nonroad
engines manufactured before 1996 typically do
not have an engine family name.
engines are similar, it may not be in proper verified use, and may result in damage to the engine or retrofit device.
DPFs may take 1.5 hours to a full day to install. DOCs usually take 1.5 -4 hours to install. Installations cost from
$170 to $500 for each engine for DOCs and DPFs.22
SCRs require installation of a tank for ammonia (or other reagent), as well as the necessary catalyst and
associated piping and controls. These retrofits can be much more involved than DPFs or DOCs.
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Alternative and Cleaner Fuels
Though retrofits minimize emissions, adopting the use of alternative fuels will also help. Most retrofit
technologies require the use of low or ultra-low-sulfur diesel. For information on where these fuels are
available, visit http://www.eere.enerqv.gov/afdc/fuels/stations.html.
CLEANUP - CLEAN AIR
DIESEL EMISSIONS & GREENHOUSE GAS REDUCTIONS

Ultra-Low-Sulfur
Diesel23
Biodiesel24
Natural Gas25
Emulsified Fuel26
Fuel
Description
Ultra-low-sulfur diesel
(ULSD) has less than 15
ppm sulfur content. Low-
sulfur diesel (LSD)
contains less than 500
ppm sulfur content.
Renewable fuel made
from animal or vegetable
fats. Can be blended
with conventional diesel.
Usually found in 2%
(B2), 20% (B20), and
100% (B100) blends.
Gas consisting mainly of
methane. In the forms of
compressed natural gas
and liquefied natural gas.
Fuel that is mixed with
water and injected with
additives to lower
combustion temperatures
which reduces NOx and
PM. Refer to the CARB
verification list (page 3)
for verified emulsified
fuels.
Emissions
Reductions
PM 13%
NOx 3%
CO 6%
HC 13%
B20
PM 10%
NOx* -2%
CO 10%
HC 21%
Sulfates 20%
COz 15%
PM 90%
NOx 50%
CO 90%
HC 50-75%
COz 25%
PM 16%-58%
NOx 9%-20%
CO 13%
HC -30% to -99%
Cost
• $0.04 -$0.05 more per
gallon than low-sulfur
diesel
• As of July'07, B20
was the same price as
conventional diesel27
• ~15%-40% less than
gasoline per gallon
• ~$0.20 more per gallon
than conventional
diesel
Considerations
• Most verified retrofit
technologies require the
use of LSD or ULSD. In
June 2006, CARB
mandated the use of
ULSD in both on- and
off-road vehicles.
Nationwide mandates
for ULSD use in on-
road engines came into
effect in 2006 and
mandates for LSD use
in off-road vehicles
came into effect in
2007.
•	Biodiesel blends lower
than B20 experience
insignificant difference
in torque, horsepower,
and fuel economy
compared to
conventional diesel.
Its greater engine
performance is
attributed to its higher
cetane number.
•	Using higher biodiesel
blends may require
changing fuel filters
and replacement of
rubber compound fuel
system components
with compatible
rubber.
•	Use biodiesel that
meets the ASTM
D6751 standard.
•	Monitor performance
in cold weather
operation and ensure
proper additives are
used to prevent
gelling.
•	Needs more frequent
fueling.
•	Natural gas vehicles
cost about $3,500 to
$6,000 more than
gasoline equivalents.
•	May affect horsepower
in some applications.
•	Can be used in any
diesel engine.
*NREL and U.S. EPA are conducting further evaluations to determine potential NOx increase.
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CLEANUP - CLEAN AIR
DIESEL EMISSIONS & GREENHOUSE GAS REDUCTIONS
Calculate Emissions Reductions
Calculate diesel emissions from cleanup and
redevelopment using EPA's online tool, The Quantifier.
http://cfpub.epa.gov/quantifier/
Funding Resources
National Clean Diesel Campaign
EPA program that works to reduce pollution resulting
from existing diesel vehicles and equipment by
encouraging fleet owners to install pollution-reducing
devices on the vehicles and to use cleaner-burning
diesel fuel. Listing of potential funding resources:
www.epa.gov/cleandiesel/qrantfund.htm
Carl Mover Clean Engine Incentive Program
Grants for private companies or public agencies
operating heavy-duty engines in CA.
www.arb.ca.qov/msproq/mover/mover.htm
U.S. DOT Congestion Mitigation Air Quality (CMAQ)
Improvement Program
The CMAQ program provides financial assistance to
areas striving to attain federal air quality standards.
State Departments of Transportation (DOTs),
Metropolitan Planning Organizations (MPOs), and
transit agencies can invest more than $1.6 billion
annually until 2009 in projects that reduce criteria air
pollutants regulated from transportation-related
sources. Clean diesel retrofit projects are eligible for
CMAQ consideration.
Contact:
Michael Koontz (202)366-2076
michael.koontz@fhwa.dot.gov
www.fhwa.dot.gov/environment/cmagpgs/
EPA Office of Research and Development
Consolidated Research/Training
Supports research and development to determine the
environmental effects of air quality, drinking water,
water quality, hazardous waste, toxic substances, and
pesticides. Available to each State, territory and
possession, and Tribal nation of the U.S., including the
District of Columbia. Eligible entities include public and
private State universities and colleges, hospitals,
laboratories, State and local government departments,
other public or private nonprofit institutions, and in
some cases, individuals who have demonstrated
unusually high scientific ability.
Contact:
Mark Thomas (202)564-4763 thomas.mark@epa.gov
htto://12.46.245.173/pls/portal30/
CATALOG. PROG RAM TEXT RPT.SHOW?
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EPA Air Pollution Control Program Support
Assists State, Tribal, Municipal, Intermunicipal, and
Interstate agencies in planning, developing,
establishing, improving, and maintaining adequate
programs for prevention and control of air pollution or
implementation of national primary and secondary air
quality standards.
Contact:
William Houck (202)564-1234 houck.william@epa.gov
htto://12.46.245.173/pls/portal30/
CATALOG. PROG RAM TEXT RPT.SHOW?
p arg names=prog nbr&p arg values=66.001
EPA Pollution Prevention (P2) Grants
Provides matching funds to state and tribal programs
to support P2 activities across all environmental media
and to develop state programs.
www.epa.gov/oppt/p2home/pubs/grants/ppis/ppis.htm
Information Resources
National Clean Diesel Campaign
www.epa.gov/cleandiesel
West Coast Collaborative
www. westco astco I la bo rat i ve. o rq
Clean Construction USA
www.epa.gov/cleandiesel/construction/
Diesel Technology Forum
www.dieselforum.org
National Biodiesel Board
www.biodiesel.org
Alternative Fuel Station Locater
http://www.eere.enerqv.gov/afdc/fuels/stations.html
Clean Diesel Fuel Alliance
www.clean-diesel.org
Manufacturers of Emission Controls Association
www.meca.org
PM Air Trends
http://www.epa.gov/airtrends/pm.html
Clean Air Task Force
http://www.catf.us/proiects/diesel/
Cleanup-Clean Air Website
www.epa.gov/region9/cleanup-clean-air
~ Cleanup-Clean Air Pilot Projects ~ Smart Energy
Resources Guide ~ Factsheets ~ Cleanup-Clean Air
Updates ~ Cleanup-Clean Air Staff Contact Info
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CLEANUP - CLEAN AIR
DIESEL EMISSIONS & GREENHOUSE GAS REDUCTIONS
Bibliography
*AII weblinks active as of October 18, 2007.
1.	U.S. EPA, www.epa.gov/ne/eco/diesel/.
2.	California Air Resources Board. "Facts about
California's Accomplishments in Reducing Diesel
Particulate Matter Emissions." www.arb.ca.gov/diesel/
factsheets/dieselpmfs.pdf.
3.	California Air Resources Board. "Facts about
California's Accomplishments in Reducing Diesel
Particulate Matter Emissions." www.arb.ca.gov/diesel/
factsheets/dieselpmfs.pdf.
4.	U.S. EPA. www.epa.gov/oar/particlepollution/
health.html.
5.	U.S. EPA, West Coast Diesel Collaborative. "West
Coast Collaborative PowerPoint." Page 4. http://
westcoastcollaborative.org/files/outreach/
WCCppt.pdf.
6.	U.S. EPA. www.epa.gov/oar/particlepollution/
health.html and www.epa.gov/air/urbanair/nox/
hlth.html.
7.	U.S. EPA, National Emissions Inventory.
www.epa.gov/ttn/chief/trends.
8.	U.S. EPA, West Coast Diesel Collaborative.
www. westco astco I la bo rat i ve. o rg.
9.	U.S. EPA, National Emissions Inventory.
www.epa.gov/ttn/chief/trends.
10.	U.S. EPA, West Coast Diesel Collaborative. June
2005.	"Public Health and Environmental Impacts of
Diesel Emissions." http://westcoastcollaborative.org/
files/outreach/Health-Envi ro-Factsheet.pdf.
11.	U.S. EPA. www.epa.gov/nonroad-
diesel/2004fr/420f04032.htm.
12.	Ibid
13.	Union of Concerned Scientists, www.ucsusa.org/
clean vehicles/big rig cleanup/sick-of-soot-solutions-
to-californias-diesel-pollution.html.
14.	Manufacturers of Emission Controls Association. April
2006.	Retrofitting Emission Controls On Diesel-
Powered Vehicles, https ://vau It.swri.ed u/Retrofit/
Documents/TechPaper.pdf.
15.	Ibid
16.	Ibid
17.	Ibid
18.	U.S. EPA, West Coast Diesel Collaborative, http://
westcoastcollaborative.org/files/outreach/Diesel%
20Emission%20Mitigation.pdf and Clean Air Fleets.
www.cleanairfleets.org/ect.html.
19.	California Air Resources Board. Oct 2000. "Appendix
XI, Diesel PM Control Technologies."
www.arb.ca.gov/diesel/documents/rrpapp9.PDF.
20.	Virginia Department of Environmental Quality.
www.deg.virginia.gov/mobile/mobcomp.html.
21.	Manufacturers of Emission Controls Association. April
2006. Retrofitting Emission Controls on Diesel-
Powered Vehicles, htt ps ://va u It. sw ri. ed u/Retrof it/
Documents/TechPaper.pdf.
22.	Washington State University. "Diesel Oxidation Cata-
lyst." www.energy.wsu.edu/documents/renewables/
DieselOxidation.pdf. And Washington State Univer-
sity. "Diesel Particulate Filters."
www.energy.wsu.edu/documents/renewables/
Retrofitparticualtefilters.pdf.
23.	Clean Air Fleets, www.cleanairfleets.org/altfuels.html.
24.	U.S. EPA. www.epa.gov/region09/waste/biodiesel/
Questions.html: www.epa.gov/otag/retrofit/documents/
biodiesel calc: and www.epa.gov/region09/waste/
biodiesel/Questions.html#benefits
25.	U.S. EPA, OTAQ. March 2002. "Clean Alternative
Fuels: Compressed Natural Gas Fact Sheet." http://
eerc.ra.utk.edu/etcfc/docs/EPAFactSheet-cng.pdfand
U.S. DOE, EERE. www.eere.energy.gov/afdc/fuels/
natural gas.html.
26.	U.S. EPA, www.epa.gov/otag/diesel/construction/
strateoies.htm. & U.S. EPA, www.epa,gov/otag/
retrofit/tech I ist-1 u b rizo I. htm.
27.	U.S. DOE, EERE. March 2007. "Clean Cities Alterna-
tive Fuel Price Report." Page 3. http://
www.eere.energy.gov/afdc/pdfs/afpr mar 07.pdf.
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