This document provides an overview of environmental product declarations (EPDs) for pavements. It discusses how full life cycle assessment considering all impacts and interactions over the full life can help advance sustainability goals. Key topics covered include quantifying impacts through life cycle assessment, developing product category rules to standardize EPDs, important processes and materials considered in pavement LCA and EPDs, and potential future developments to improve sustainability evaluation. The document aims to explain how EPDs can be used along with other tools to optimize pavement design, materials selection, and management over the full life cycle.

1. Environmental Product Declarations
An Overview
John Harvey, Ali Butt
University of California Pavement Research Center
City and County Pavement Improvement Center
CalAPA
EPD Workshop
Sacramento
25 October 2023

2. How do we advance towards sustainability?
• Is it just reducing global warming potential (GWP) and making sure we are
recycling?
• Good answers will come from full system and complete life cycle-based decision
making
• Full System for pavement considers:
– Resources, processes, context of structure/traffic/climate/soil
– All environmental and resource use impacts of interest
– Interactions and effects on other systems
• Complete Life Cycle for pavement:
– Looks at consequences of current decisions as far into the future as can be calculated with
some certainty
– Looks at effects of current decisions on ability to make future decisions
• Need to set sustainability goals and routinely use quantitative approaches in
our work to address and work towards those goals

3. Reducing Pavement Costs and Environmental Impacts
• Planning:
– Environmental justice of impacts and benefits of pavement
– Inclusion of active transportation & multi-modal
• Asset management:
– Optimizing programming of preservation, maintenance, rehabilitation,
reconstruction
• Design:
– Use less material or less impactful materials to achieve same life
• Materials Processing
– Contractor optimizes material for cost to meet performance and environmental
impacts (EPD)
• Construction Specifications:
– Use construction quality control to get maximum life from materials; Measure
the quality; Enforce the specifications
– Allow use of lower impact materials if same or better life
• Operations:
– Minimizing construction work zones
– Minimizing energy/fuel use from pavement vehicle interaction
• Preservation, Maintenance, Rehabilitation
– Extend the life of materials with preservation
– Provide structural capacity for heavy vehicles
• Reconstruction, recycling
– Rebuilding worn out pavements with minimal new materials
Planning
Asset Management

4. How to Quantify Impacts:
Environmental Life Cycle Assessment (LCA or eLCA)

5. LCA Models Product Life Cycle and Flows
Kendall (2012)

6. - Rolling resistance
- Albedo: heat
island & lighting
- Leachate
Pavement Life Cycle
Materials
Acquisition and
Production
Construction /
Maintenance &
Rehabilitation
Use End-of-life
- Material
extraction and
production
Transport
- Equipment Use
- Transport
- Traffic delay
- Recycle
- Landfill
From: Kendall et al., 2010
R : Recycle
6
Transport
R
R

7. Four Key Stages of Life Cycle Assessment
Interpretation
Goal
Definition
and Scope
Life Cycle
Inventory
Assessment
Impact
Assessment
Define questions
to be answered
(sustainability
goals) and
system to be
analyzed
The “accounting”
stage where
track inputs and
outputs from the
system
Where results
are translated
into meaningful
environmental
and health
indicators
Figure based on ISO 14040, adopted from Kendall
Where the
results of the
impact
assessment are
related back the
questions asked
in the Goal
Critical Review

8. Where does life cycle inventory data come from?
• Measure it yourself
• Buy it
– Thinkstep (GaBi)
– Simapro
– EcoInvent
• Open source data
– USLCI
– Federal LCA Commons
“OpenLCA”
• Industry
– Environmental Product
Declarations

9. Basic Unit Process Used in LCA
FHWA LCA tool Goal and Scope
• Example processes:
• Produce one ton of asphalt concrete
• Produce one cubic yard of concrete
• Pave 10 lane-km of concrete
• Compact 1,000 m2 of asphalt concrete
• Haul 25 tons of aggregate base
• Place a slurry seal

10. “Balancing” with Multiple Unit Processes
eLCAP User Manual
• Typical pavement project will have hundreds of unit processes: materials, electricity, diesel,
construction equipment use
• “Balancing” means scaling the amount of input and output to the functional unit to create LCA
model of the system
• The LCA model results in the life cycle inventory of the pavement project: flows in and flows out

11. How are life cycle impacts calculated?
• Mid-Point Indicators:
Pollutant and resource
inventory flows are used to
mid-point impact indicators
– Calculated from models
– Stated in terms of equivalent
units of a single pollutant
• End-Point Indicators:
summarize impacts on
humans and the
environment
– Determined from mid-point
indicators
• Different mid-point
indicator systems:
– TRACI (US EPA)
– CML (Europe)

12. Example:
Calculation of
mid-point
indicators GWP
CO2-eq
and Smog O3-eq
from air
emissions

13. • Global warming
• Stratospheric ozone depletion
• Acidification
• Eutrophication
• Photochemical smog
• Terrestrial toxicity
• Aquatic toxicity
• Human health
• Abiotic resource depletion
• Land use
• Water use
US EPA Mid-Point and End-Point Impact Assessment Categories
(TRACI – Tool for the Reduction and Assessment of Chemical and other environmental Impacts)
Impacts to people
From Saboori Image sources: Google
Impacts to ecosystems
Depletion of resources

14. Other types of
environmental impact:
8 hour ozone non-
attainment by county
(2015)
Not just GWP is
important
https://www3.epa.gov/airquality/greenbook/map/map8hr_2015.pdf

15. Cradle to Gate LCA for Material
= Environmental Product Declaration
Some slides adapted from Nick Santero @ Rivian

16. Life cycle stages
for building
product EPDs
with boundary
conditions for
different LCA
scopes
A1-A3 is typical
current scope
(adapted from ISO 21930:2017)

17. PCR, LCA, EPD Definitions and Relationships
17
Product Category Rule (PCR)
“Set of specific rules, requirements, and guidelines for
developing Type III environmental product declarations
for one or more product categories” (ISO 14025, 21930,
EN15804); update every 5 years
PCR: the framework
Life Cycle Assessment (LCA)
“Compilation and evaluation of the inputs, outputs and
the potential environmental impacts of a product system
throughout its life cycle” (ISO 14040, EN15304, FHWA)
LCA: the analysis
Environmental Product Declaration (EPD)
“Providing quantified environmental data using
predetermined parameters and, where relevant,
additional environmental information” (ISO 14025, ISO
21930, EN15804)
EPD: the declaration
Adapted from N. Santero, thinkstep

18. 18
Product Category
Rules
Life Cycle Assessment
Environmental
Product Declaration
PCR, LCA, and EPD – Relationships
Reviewed through (1) Public comment
and (2) an expert review panel
Reviewed by an
LCA expert
Reviewed by the
“Program Operator”

19. Organize
• Engage industry
• Identify program operator
• Determine scope
• Create PCR committee
Draft
• Consult similar PCRs
• Consult existing LCAs
• Develop draft based on group
consensus
Review and Verify
• Public comment
• ISO panel review
• Publication by program operator
• Ensures comprehensive system boundaries,
quality data, etc.
PCR Development Process
19
Product Category
Rules (PCR)

20. Crude Oil
Extraction
Crude Oil Refining
Products
- Gasoline
- Diesel
- Kerosene
- Asphalt binder
- Other useful fuels
Storage
(terminal
processes)
Asphalt Mixture
Production (at
asphalt plant)
Crushing
and Sieving
Additive
and/or Rejuvenator
Raw Material
Acquisition
Existing RAP
Stockpile
Fractionation
Unfractionated
Aggregate
Quarrying
Storage/
Stockpiling
Product
Processing
Storage
T T
T
T T
Asphalt binder, T
Crushed
aggregate,
T
Additive/
Rejuvenator,
T
RAP from Same
Project
RAP from
Different Project
Fractionated RAP, T
Unfractionated RAP, T
E
W, e
E
E E E
E
E E
E
E
W, e
W, e
W, e
W, e
W, e
W, e
E = Energy
(Electricity,
Renewable/nonre
newable Fuel)
T =
Transportation of
materials
W = Waste
e = emissions to
air, water, land
Asphalt Mixture
System
Boundary &
Supply Chain

21. Other things used in asphalt mixes
• SBS polymer
– 3% SBS = 35% more GWP
in binder impact
– Is this compensated for
by increased life so net
result is better?
• Ground tire rubber (TB)
Asphalt Institute LCA 2019
• RAP
• RAP contents greater than about 20-25% may require
rejuvenating agents to get blending/softening with high
RAP binder contents
• Petroleum distillates
• Bio-based: non-food vegetable oils, tall oils

22. • Data from secondary sources
• Represent upstream operations
• Sources
• Public Databases
• Industry inventory data
• EPDs
• Data from onsite
operations
– Inputs and outputs from
specific site(s)
– Measure onsite energy
consumption, material
consumption, emissions,
waste, etc.
• Can be specific or
averages
– Site
– Company
– Industry
Primary Data
Data
22
Secondary Data

23. Environmental Product Declaration (EPD)
23
Providing quantified environmental data using predetermined parameters
and, where relevant, additional environmental information (ISO 14025)
Summary of the LCA
– Presents selected results
– Includes key methodological information
– Follows rules set by the PCR
– Includes additional environmental information, as relevant
Designed to be “market facing”
– Publically available
– Enables consumers to compare environmental impacts
– Published through Program Operator → establishes credibility via review

24. ISO EPD Standards
• ISO 14025: 2006 - Environmental labels and declarations
– Uses 14040 series of standards in the development of Type III
environmental declaration programs and Type III environmental
declarations.
o ISO 14040:2006 – Environmental Management, LCA Principles/Framework
o ISO 14044:2006 – Environmental Management, Requirements & Guidelines
• ISO 21930:2017- Sustainability in buildings and civil
engineering works
– Complements ISO 14025 by providing specific requirements for the
EPD of construction products and services.

25. Quick Summary on ISO 21930:2017
• Core rules for EPDs of construction products and services
• Provides capability to North Americans to use ISO21930 instead of EN15804
• Aligns with EN15804
• Provides detailed additional guidance in areas:
– Functional/Declared Unit
– System Boundary
– Reference Service Life
– Allocation
– Comparability
– Average EPDs
– End of Life Modelling
– Other critical areas of LCA
• LCIA Defaults to TRACI for North America
• No cut-off for Hazardous Materials
• 5% cut-off rules per module but 1% cap on unit processes
• Sensitivity Analysis “SHOULD” be performed
Overall: ISO20930 is a rigorous
document providing more guidance
on PCRs/EPDs for civil constructoin
products and services than ISO
14025

26. NAPA PCR: Data Gaps
• Mix additives (added directly to the mix)
– Liquid antistrip additives
– Warm-mix additives
– Recycling agents, rejuvenators, and softeners
– Fibers
– GTR (only considered as a terminal blend binder additive)
– Pigments
• Binder additives (blended with the binder at the terminal)
– Polymers, including elastomers and plastomers
– Pigments
– Binder extenders
– Odor neutralizers
• Asphalt emulsions
• Slag aggregates, including steel slag and blast furnace slag

27. What are the main contributors to A1-A3 GWP in a mix
• Heating of the mix (averaged/ton over a year, all mixes)
• Binder
– Content
– Currently must use industry average because no no individual
binders EPDs (underway at Asphalt Institute)
• Use of lime (lime is 1.2 times more GWP intensive than cement)
• Transportation of aggregate and binder to plant
• Aggregate production
• Electrical energy use of the plant (averaged/ton over a year, all
mixes)
• Diesel for plant operations
• Additives such as rejuvenating agents, warm mix asphalt
additives, extender oils

28. What are the main things that are in producer’s control
• Binder content
– Don’t want to drive it down, hurts durability
– RAP replacement of virgin binder
– Rejuvenator (but need an EPD for the rejuvenator to
account for its emissions)
• Admixtures
• Transportation of aggregate
– Trucking aggregate from quarry to off-quarry plant
• Fuel for mixing
– California: all use natural gas, other states have worse
choices
– WMA can reduce fuel use if reduces , but need to include
EPD for WMA additive
• Aggregate mining efficiency (diesel and electricity) Image FHWA

29. eLCAP examples of some mix component contributions to GWP
(kgCO2e/tonne of mix)
Mix Type
HMA
Production
(Cradle-Gate)
Aggregate
Production
Bitumen
Production
HMA-Energy
(at Plant
Only)
Fractionated
RAP
Production
Additives
Production
HMA
Transport
(Cradle-
Gate)
HMA (25% RAP, no rejuv.) 55 2.1 17 22 0.011 - 14
HMA (15% RAP, no rejuv.) 57 2.3 18 22 0.008 - 15
HMA (0.94% Hydrated lime dry
slacked)
64 2.0 17 22 0.013 9 14
RHMA-G (0.19% Extender oil) 78 2.6 26 24 - 6 20
• *Rejuvenating agent and warm mix additives may have very intensive GWP contributions for small
amounts, need to be calculated with natural gas reduction for lower mixing temperatures and RAP
replacement of virgin binder
• EPDs are just becoming available

30. What are main things not in producer’s control
• Binder source impacts
– Currently have to use Asphalt Institute 2019 LCA
continental average
• Use of lime by specification
• Ability to measure natural gas use for a specific
type of mix, such as WMA
– Currently average across all mixes for a year
• Availability of EPDs for rejuvenating agents,
warm mix additives, liquid anti-strip additives
– This is getting better

31. What are important things that a producer can
control in the future
• Binder source once Asphalt Institute
finishes PCR and starts EPD program
• Better consideration of additives using
data from EPDs for RA, WMA, LAS
• Potential for partial bio-based binders
– How to account for bio based binder carbon
sequestration?
Image California Energy Commission

32. California asphalt
binder sources
(UCPRC study for
Caltrans)
Foreign Crude oil (56%)
Domestic Crude oil (44%)
US: Crude oil mix (California)
[32%]
US: Crude oil mix (Alaska)
[12%]
California
Crude Oil
Mix
SA: Crude oil mix (27%)
EC: Crude oil mix (13%)
CO: Crude oil mix (9%)
CA: Crude oil mix (2%)
BR: Crude oil mix (5%)
Saudi Arabia (SA)
Canada (CA)
Ecuador (EC)
Colombia (CO)
Brazil (BR)

33. 2017 UCPRC Calculated Binder and Additives Impacts
0.455 0.475 0.637
2.83
2.16
1.12
7.09
1.12
7.19
0.000226 0.000226
UCPRC
Asphalt
binder
2017
eLCAP
Asphalt
binder
(Eurobitume)
AI
Asphalt
binder
2019
Advera
Evotherm
SonneWarmix
CECABASE
Sasobit
Rediset
Gencor
Astec
GWP
(kg
CO
2e
)
per
kg
of
Material
Maryam Ostovar Doctoral Thesis, UC Davis 2022

34. What are
important
things not
considered in
A1-A3 EPDs but
may be in near
future
• Transportation
distance plant to
site (A4)
• Construction diesel
use (A5)

35. The other use of EPDs! input to Whole Life LCA
• Whole life LCA such as with eLCAP, considering
– EPDs provide data for new materials for which data not available
• Whole life also considers:
– Transport to site
– Construction
– M&R
– Pavement vehicle interaction
– End of life

36. • Use of
EPD data
for:
– Network
manage-
ment
– Planning
– Project
design

37. www.ucprc.ucdavis.edu
www.ucprc.ucdavis.edu/ccpic
jtharvey@ucdavis.edu
Questions?

38. NAPA Product Category Rules
Objective: provide the rules, requirements, & guidelines for the
development of an EPD for asphalt mixtures that are produced in the
US & Canada.
• The PCR complements ISO 21930:2017 (although additional
requirements are also included and called out in the PCR)
• Document by Mukherjee, A. (2021), “Updates to the Life Cycle
Assessment for Asphalt Mixtures in Support of Emerald Eco Label
Environmental Product Declaration Program” serves as the
foundation for the NAPA PCR

39. A walk through the NAPA PCR
• Functional/Declared Unit
– Declared unit shall be one metric tonne (one short ton) of asphalt mixture
– No functional unit established (EPD will be data source for pavement LCAs)
• Secondary Materials
– Aggregate and asphalt binder replacements
o Baghouse fines, glass cullet, RAP, RAS
– Additive replacements
o Ground tire rubber, recycled fibers
• Secondary Fuels
o Landfill gas, liquid biofuels, recycled fuel oil, renewable natural gas

40. A walk through an
EPD
• Company Information
• Product Description (usually general
information)
– Job mix formula is NOT included
– Ingredients
• EPD general information
– Issue and validity dates
– Declaration unique number
– Developer/s and reviewer/s
– EPD producing tool
– Etc.
https://asphaltepd.org/epd/d/XZUmym/
EXAMPLE EPD

41. A walk through
an EPD
• Methodology
– Declared unit
– Brief descriptions on:
• Life cycle stages, LCI,
allocation procedures, cut-
off, limitations,
comparability, LCA

42. A walk through
an EPD
• Limited TRACI Results
– Global Warming Potential
(GWP100)
– Ozone Depletion Potential
– Eutrophication Potential
– Acidification Potential
– Photochemical Ozone Creation
Potential

43. A walk through
an EPD
• Material and Resources
Results
– Renewable Energy
– Non-Renewable Energy
– Secondary Materials
– Fresh Water Consumption
– Abiotic Depletion Potential

44. A walk through
an EPD
• Waste and Material Flow
Indicator results (if
calculated/available)
• And Additional Carbon
Indicators Results

45. A walk through
an EPD
• References are also
provided