Waste and Materials-Flow Benchmark Sector Report: 

Beneficial Use of Secondary Materials -

Coal Combustion Products

Economics and Risk Analysis Staff

Office of Resource Conservation and Recovery

Office of Solid Waste and Emergency Response

U.S. Environmental Protection Agency

Washington, D.C. 20460

April 2011

Revised July 19, 2011
ACKNOWLEDGMENTS

Industrial Economics, Incorporated (IEc), under contract with EnDyna, Inc., is responsible for the overall 

organization and development of this report. This report was developed with the assistance of Dr. H. 

Scott Mathews of the Carnegie Mellon Green Design Institute, Dr. Jim Boyd of Resources for the Future, 

Dave Goss of the American Coal Ash Association (ACAA), and with input and data from various EPA 

Office of Resource Conservation and Recovery and Office of Policy Economics and Innovation 

representatives. Lyn D. Luben of the U.S. Environmental Protection Agency, Office of Resource 

Conservation and Recovery, provided guidance and review.
i

TABLE OF CONTENTS 

EXECUTIVE SUMMARY ES-1

CHAPTER 1: INTRODUCTION 1-1

Overview of the Report 1-1

Organization of Report 1-2

CHAPTER 2: BASELINE CHARACTERIZATION OF CCP GENERATION AND 

BENEFICIAL USE 2-1

Current Quantities of CCPs Generated and Managed 2-3

Beneficial Use Options 2-5

CHAPTER 3: MARKET STRUCTURE OF BENEFICIAL USE FOR CCPs 3 -1

Coal-Fired Utility Practices: CCP Supply 3-1

Intermediaries 3-3

End-Users and Purchasers: CCP Demand 3-3

Market Dynamics of Specific Use Applications 3-5

Concrete 3-7

Gypsum Wallboard 3-8

CHAPTER 4: IMPACTS ASSOCIATED WITH BENEFICIAL USE OF CCPs 4- 1

Life Cycle Inventory Analysis and EPA Program Outcomes 4-1

Life Cycle Assessment and Economic Benefit Assessment 4-2

Assessment of Beneficial Impacts of CCP Use 4-3

Methodology for Evaluating Unit Impacts of Beneficial Use 4-5

BEES Analysis of Use of Fly Ash in Concrete 4-6

SimaPro Analysis of FGD Gypsum in Wallboard 4-7

Allocation of Life Cycle Impacts to CCPs 4-7

Results 4-9

Limitations and Assumptions 4-11

CHAPTER 5: ESTIMATING PROGRAM LEVEL IMPACTS 5-1

Development of Defensible Beneficial Use Scenarios 5-1

Current Market Dynamics: Factors Affecting Beneficial Use 5-1

Structural Changes to the Market 5-3

Attribution of Impacts to EPA Programs 5-3

Beneficial Impacts Associated with Current Use of CCPS 5-5
ii

Economic Distribution of CCP Beneficial Use Impacts 5-8

Conclusions and Next Steps 5-8

REFERENCES R-1

APPENDIX A: KEY BENEFICIAL USE APPLICATIONS FOR CCPS 

APPENDIX B: USE OF LIFE CYCLE ASSESSMENT IN EVALUATION OF ECONOMIC 

BENEFITS 

APPENDIX C: ANALYSIS OF BENEFITS USING ALTERNATE LIFE CYCLE MODELS

APPENDIX D: DETAILS OF LIFE CYCLE INVENTORY ANALYSIS METHODOLOGIES

APPENDIX E: POTENTIAL IMPACTS OF ALLOCATION OF LCI RESULTS TO CCPS
iii

Note on Updates to Quantitative Estimates in Document:

This document updates a 2008 version of this report. Quantitative and monetized benefits 

estimates have changed significantly from the prior analysis to reflect new life cycle inventory 

data, updated model versions (BEES 4.0), updated estimates of current beneficial use, and 

refined approaches to monetizing impacts. Specifically, updates reflect the following:

 Revised energy mix: The energy mix used for the SimaPro analysis for FGD 

Gypsum in wallboard reflects data that are updated from Franklin US 98 

“Electricity avg. kWh USA” data set to the Ecoinvent 2.0 “Electricity, medium 

voltage, at grid/US” data set. This substitution resulted in significant changes in 

environmental impacts across all aspects of the analysis.

 Updated water use data: The change in energy mix from the Franklin US 98 data 

set to the Ecoinvent 2.0 data set in the SimaPro analysis for FGD Gypsum 

resulted in a subsequent increase in water usage because of the inclusion of water 

used in turbines. We do not attempt to monetize the total quantity estimates of 

water used.

 Primary Energy: An error in the total primary energy calculation for FGD 

Gypsum was corrected, resulting in a significant decrease in total primary energy.

 Current use: The extrapolated current use quantities for fly ash in concrete and 

FGD gypsum in wallboard were updated from the 2005 estimates using the 

American Coal Ash Association’s Coal Combustion Products Survey from 2008. 

 Pricing: The monetized energy impacts for fly ash were calculated using a price 

figure from the average price of purchased energy to the cement manufacturing 

industry in 2006 and converted to 2009 dollars using NASA’s GDP Deflator 

Inflation Calculator. The monetized energy impacts for FGD Gypsum were 

calculated using a price figure derived from the average cost of diesel fuel in 

2009. The monetized water impacts were calculated using the NUS Consulting 

Group’s average water cost estimates for 2008 converted to 2009 dollars using the 

NASA calculator. 
ES-1

EXECUTIVE SUMMARY

INTRODUCTION

The U.S. Environmental Protection Agency’s Office of Resource Conservation and Recovery (EPA 

ORCR) is currently developing methods to evaluate the environmental, human health, and economic 

outcomes of specific EPA programs. As an initial step, ORCR is examining the extent to which the costs 

and benefits of source reduction, reuse, and recycling may be quantified for a range of materials targeted 

by the Sustainable Materials Management (SMM) program (formerly known as the Resource 

Conservation Challenge (RCC)). 

Coal combustion products (CCPs) are among the materials targeted by EPA’s SMM program. The SMM 

program is designed to facilitate changes in the economics and practice of waste generation, handling, and 

disposal (e.g., by promoting market opportunities for beneficial use). Two potential milestones for 

increasing CCP beneficial use are as follows:

 Increase overall beneficial use of CCPs to at least half of total generation; and

 Increase the use of coal fly ash in concrete by significant percentage over 10 years (e.g., increase 

of over half from 2001 beneficial reuse).

Coal combustion residues (CCRs) are formed during coal-burning processes in power plants and 

industrial boilers. Coal combustion produces various forms of CCRs, which are categorized by the 

process in which they are generated. CCPs are the subset of CCRs that are targeted for beneficial reuse; 

this document uses the term broadly to describe all categories of CCRs in which some portion have been 

beneficially used. Common CCPs include: fly ash, bottom ash, flue gas desulphurization (FGD) material, 

boiler slag, fluidized bed combustion (FBC) ash, and cenospheres. CCPs may be beneficially used as a 

component of building materials or as a replacement for other virgin materials such as sand, gravel, or 

gypsum. Size, shape, and chemical composition determine the suitability of these materials for beneficial 

use. Higher value applications, such as use in cement or concrete products, require moderately stringent 

specifications (in terms of size, shape and chemical composition), whereas lower value uses, such as 

structural or mining fills, can accept more variable materials.

This report serves two purposes: (1) To provide an initial assessment of the market dynamics that affect 

the generation, disposal, recovery, and beneficial use of CCPs; and (2) to provide a preliminary life cycle 

inventory analysis of the beneficial impacts of CCP use, including an initial estimate of the baseline 

beneficial use impacts with current (2008) CCP levels and an estimate of the beneficial impacts 

associated with increasing use of fly ash in concrete to 18.6 million tons (an increase of roughly 50 

percent over the 2001 estimated use of 12.4 million tons).

CCP GENERATION AND MARKET DYNAMICS

The American Coal Ash Association (ACAA), a trade association whose purpose is to advance the 

beneficial use of CCPs, reports that the electric power industry generated approximately 136 million short 

tons of CCPs in 2008. Of these, the industry disposed of approximately 75 million short tons to landfills, 

while beneficially using approximately 61 million short tons in products.1 Exhibit ES-1 summarizes 

 

1 The ACAA survey is administered to both ACAA members and non-members. ACAA members account for approximately 40 percent of private 

power generation. Not all survey recipients complete the survey each year. ACAA extrapolates survey respondent data to the entire coal-fired 

electricity generation industry. ACAA includes mining applications as a beneficial use, but EPA considers large fill operations to be disposal. 

Therefore, total beneficial use figures and percentages presented in this report may overstate what EPA considers to be beneficial use. EPA, 2010, 
ES-2

results of the most recent (2008) ACAA survey of generators of CCPs, which indicates that the most 

common beneficial use applications for CCPs are as a replacement for virgin materials in concrete and 

cement-making, structural fill, and gypsum wallboard. 

The CCP beneficial use market is composed of three primary segments. These are:

 Generators: An estimated 495 coal-fired electric utility plants currently operate in the United 

States.2 Since the coal power industry consumes approximately 92 percent of all U.S. coal, it is 

responsible for producing the vast majority of CCPs in the country. Other industries that use coal 

as a fuel source in commercial or industrial boilers (e.g., mineral and grain processors) also 

produce small quantities of CCPs. Several factors influence a generator’s decision to either 

dispose or seek beneficial use options for spent CCPs. Key considerations include the costs of 

landfill disposal, transport, processing, storage, and marketing. 

 Intermediaries: Some coal-fired utilities market CCPs for beneficial use through a third-party 

instead of selling directly to users. In these cases, a utility perceives an efficiency in outsourcing 

the marketing of its CCPs. Marketers typically accept all of a generator’s CCPs as a service to the 

company, sell the marketable portion, and dispose of the portion that is not salable. The marketer 

typically bears the cost of hauling CCPs from the utility and the liability associated with moving 

or storing the materials. 

 End-Users: Several economic factors determine an end-user’s decision to use CCPs in its 

product. These factors include: the price of CCPs relative to the price of virgin materials for 

specific uses; the technical fit between CCPs and the use application; access to sufficient 

quantities of CCPs; and federal and state policies associated with CCP use.

Additionally, EPA is currently undertaking a rulemaking that would implement management criteria for 

coal combustion residuals (CCR) generated by electric utilities and independent power producers. The 

purpose of the rule is to address risks associated with the disposal of these wastes in landfills and surface 

impoundments. As part of this rulemaking, EPA strongly supports the beneficial use of fly ash in the 

manufacture of concrete, FGD Gypsum in the manufacture of wallboard, and fly ash in the manufacture 

of bricks (cinder blocks), so long as this beneficial use is conducted in an environmentally sound manner. 

These beneficial uses are known to result in significant environmental benefits, both locally and globally.

 

“ Hazardous and Solid Waste Management System; Identification and Listing of Special Wastes; Disposal of Coal Combustion Residuals from Electric 

Utilities; Proposed Rule,” 75 FR 118 (June 21, 2010), p. 35148.

2 EPA, 2010, “Regulatory Impact Analysis for EPA’s Proposed RCRA Regulation Of Coal Combustion Residues (CCR) Generated by the Electric Utility 

Industry,” EPA-HQ-RCRA-2009-0640-0003.
ES-3

EXHIBIT ES-1: ACAA SURVEY OF KEY BENEFICIAL USE APPLICATIONS FOR CCPS IN 2008 (MILLION 

SHORT TONS)

APPLICATION 

(INDUSTRY)

COAL 

FLY ASH

BOTTOM 

ASH

FGD 

GYPSUM

FGD MATERIAL 

WET SCRUBBERS

FGD MATERIAL 

DRY SCRUBBERS

FGD 

OTHER

BOILER 

SLAG

FBC 

ASH TOTAL

Concretea

(Construction) 12.59 0.72 0.68 0 0.02 0 0 0.004 14.02

Structural fillb

(Construction) 8.01 3.00 0 0 0.13 0.11 0.18 0.08 11.50

Mining 

applicationsc 0.96 0.06 0 0.69 0.11 0 0.003 8.64 10.47

Wallboardd 

(Construction) 0 0 8.53 0 0 0 0 0 8.53

Raw feed for 

cement clinkere

(Construction) 3.17 0.61 0.41 0 0 0 0 0 4.20

Waste stabilizationf

(Waste Mgmt) 2.92 0.08 0.74 0 0.001 0.03 0 0 3.78

Road baseg 1.03 0.77 0 0 0 0 0 0.01 1.80

Total - Key Uses 28.69 5.24 10.37 1 0.26 0.14 0.18 8.73 54.30

Total - Other 

Usesh

1.45 2.83 0.29 0.00 0.08 0.00 1.51 0.13 6.29

TOTAL - ALL USES 30.14 8.08 10.65 0.69 0.35 0.14 1.69 8.86 60.59

2008 QUANTITY 

GENERATED 72.45 18.43 17.75 12.98 1.40 1.54 2.03 9.49 136.07

CCP UTILIZATION 

RATEg 42% 44% 60% 5% 25% 9% 83% 93% 45%

Notes:

a. CCPs are frequently used as a replacement for a portion of portland cement in the manufacture of concrete.

b. Structural fill is an engineered material that is used to raise or change the surface contour of an area and to provide ground 

support beneath highway roadbeds, pavements and building foundations. It can also be used to form embankments.

c. FBC ash and other CCPs can be used in mine reclamation to refill mines and to help mitigate acid mine drainage. EPA considers 

large fill operations such as this use to be disposal and not a beneficial use (75 FR 118 p. 35148).

d. FGD gypsum is used as a substitute for virgin gypsum in wallboard manufacturing.

e. CCPs can be blended with limestone or shale in the cement kiln to make clinker, which is then ground into Portland cement.

f. The chemical properties of CCPs make them effective stabilizers of biosolids (i.e., sludge from municipal waste water treatment).

g. Coal ash is used as in ingredient in road base and sub-base.

h. Presents quantities beneficially used in minor applications not included in this exhibit, but listed in Appendix A.

i. CCP utilization rates reflect all use applications, some of which are omitted from this table but are included in Appendix A.

Utilization rates are calculated by dividing the total quantity used by the total quantity generated.

Sources: 

1. ACAA, “2008 Coal Combustion Product (CCP) Production and Use Survey,” accessed Oct. 18, 2010 at 

 http://acaa.affiniscape.com/associations/8003/files/2008_ACAA_CCP_Survey_Report_FINAL_100509.pdf. 

2. Western Region Ash Group, “Applications and Competing Materials, Coal Combustion Byproducts,” accessed at 

 http://www.wrashg.org/compmat.htm.
ES-4

ESTIMATING THE IMPACTS OF THE BENEFICIAL USE OF CCPS

To quantify the environmental impacts of increased beneficial use of CCPs in various applications, we 

use a life cycle inventory analysis approach, as both a first step in an economic analysis, and, where 

economic analysis is not practical, as a meaningful proxy.

To estimate beneficial impacts of CCP use, we first develop preliminary estimates of the incremental 

impacts associated with using a specific quantity (e.g., one ton) of CCPs in different applications. These 

impacts can then be extrapolated in specific scenarios designed to address program-level outcomes. To 

fully capture the beneficial impacts of EPA program achievements, it is necessary to model each 

beneficial use application of all CCPs targeted by the SMM. However, the time, data, and resources 

required to perform this task are beyond the scope of this report. For this preliminary analysis, therefore, 

we have selected two common CCPs, fly ash and FGD gypsum, whose beneficial use applications are

well understood, and for which life cycle modeling options and existing data are available. 

We conduct separate analyses to evaluate incremental changes in emissions, energy, and water use

associated with beneficially using a specific quantity (e.g., one ton) of fly ash and FGD gypsum. We use

two life cycle modeling applications, Building for Environmental and Economic Sustainability (BEES)

4.0 and SimaPro with EcoInvent v2.2 data, to provide the inventory data we used. Both models have 

been peer-reviewed and evaluate a large suite of environmental metrics. We employ BEES to investigate 

the changes in emissions to the environment that result from using one short ton of fly ash as a substitute 

for finished portland cement in concrete, and SimaPro to evaluate the use of one short ton of FGD 

gypsum as a substitute for virgin gypsum in wallboard. Both analyses assume that the beneficial use 

material (fly ash or FGD gypsum) substitutes for virgin material (finished portland cement or virgin 

gypsum) on a one-to-one, mass-based basis. 

While it is not optimal to use two different models in a single analysis, in this case we employed the 

BEES tool to be consistent with previous analyses of beneficial use of materials in other reports; BEES 

does not address gypsum. This analysis is designed to examine the general magnitude of potential 

environmental impacts, and the use of SimaPro for specific materials not addressed in BEES provides

additional insights into the potential impacts of beneficial use of CCPs. Exhibit ES-2 below presents the 

results of the BEES and SimaPro analyses. Negative values indicate a reduction in emissions or use of 

energy or water associated with using recycled materials in place of virgin materials. Positive values 

suggest an increase in emissions or impacts. We express beneficial use quantities in short tons (consistent 

with EPA and ACAA), but report impacts in metric units, consistent with BEES and SimaPro results.

The results of the fly ash and FGD gypsum analyses suggest many positive environmental impacts from 

beneficial use. For most metrics, there is a significant difference between the unit impact value for fly ash 

and FGD gypsum. The difference in unit impact values reflects different avoided processes when fly ash 

is used to offset portland cement versus when FGD gypsum is used to offset virgin gypsum. For example, 

the primary driver of benefits when fly ash is used in concrete is avoided raw materials extraction and 

avoided portland cement production.3

In comparison, the primary driver of benefits when FGD gypsum is used in wallboard is avoided virgin 

gypsum extraction and the processing of virgin gypsum into stucco. Portland cement production generates 

relatively high greenhouse gas emissions. Thus, the avoided CO2 and methane emissions are greater for 

 

3

It is unclear from the documentation provided for BEES what impacts (e.g. virgin materials extraction, plant infrastructure, etc.) are modeled for 

portland cement production. For this reason, it is not possible to explain the differences in unit impact results between the FGD gypsum and fly 

ash analysis.
ES-5

fly ash than for FGD gypsum in this analysis. In contrast, gypsum mining requires higher quantities of 

water and the life cycle data in EcoInvent includes water used in turbines for power generation, so water 

savings are much greater for FGD gypsum in this analysis than for portland cement. In addition, the 

difference in unit impacts likely reflects minor differences in the system boundaries in each analysis and 

the data sets utilized by each model.

EXHIBIT ES-2: INCREMENTAL BENEFICIAL IMPACTS OF USING FLY ASH IN PORTLAND CEMENT AND 

FGD GYPSUM IN WALLBO ARD

AVOIDED IMPACTS

PER 1 TON FLY ASH AS PORTLAND 

CEMENT SUBSTITUTE IN CONCRETEf

PER 1 TON FGD GYPSUM IN 

WALLBOARDf

ENERGY USE

NONRENEWABLE ENERGY (MJ)a 5,361.70 1,319.69

RENEWABLE ENERGY (MJ)

b 0.00 14.56

TOTAL PRIMARY ENERGY (MJ) 5,361.70 1,334.25

TOTAL PRIMARY ENERGY (US$)c 23.59 21.67

WATER USE

TOTAL WATER USE (L) 689.36 88,973.02

TOTAL WATER USE (US$)

d 0.44 67.39

GREENHOUSE GAS EMISSIONS

CO2 (G) 995,744.68 78,830.56

METHANE (G) 842.55 171.71

AIR EMISSIONS

CO (G) 1,378.72 38.04

NOX (G) 2,680.85 152.43

SOX (G) 2,451.06 192.01

PARTICULATES GREATER THAN PM10 (G) 0.00 1,209.24

PARTICULATES LESS THAN OR EQUAL TO PM10 (G) 7.66 472.58

PARTICULATES UNSPECIFIED (G) 2,374.47 0.00

MERCURY (G) 0.08 0.00

LEAD (G) 0.00 0.03

WATERBORNE WASTES

SUSPENDED MATTER (G) 490.21 12.63

BIOLOGICAL OXYGEN DEMAND (G) 22.98 23.11

CHEMICAL OXYGEN DEMAND (G) 45.96 24.14

COPPER (G) 0.00 0.00

MERCURY (G) 0.00 0.00

LEAD (G) 0.00 0.01

SELENIUM (G) 0.00 0.01

NONHAZARDOUS WASTE (KG)e 0.00 Not reported
ES-6

AVOIDED IMPACTS

PER 1 TON FLY ASH AS PORTLAND 

CEMENT SUBSTITUTE IN CONCRETEf

PER 1 TON FGD GYPSUM IN 

WALLBOARDf

Notes:

a. Nonrenewable energy refers to energy derived from fossil fuels such as coal, natural gas and oil.

b. Renewable energy refers to energy derived from renewable sources, but BEES does not specify what sources these 

include.

c. We monetize energy impacts for fly ash using a price figure ($0.0044/MJ) derived from the average price of purchased 

energy to the cement manufacturing sector in 2006 ($4.36/million BTU), from Table 7.2, accessed on Nov. 16, 2010 at 

http://www.eia.doe.gov/emeu/mecs/mecs2006/2006tables.html. The cost was converted to 2009 dollars using NASA's 

Gross Domestic Product Deflator Inflation Calculator, accessed on April 22, 2010 at 

http://cost.jsc.nasa.gov/inflateGDP.html. We monetize energy impacts for FGD Gypsum using a price/MJ figure 

($0.0179/MJ), derived from the average cost of diesel fuel in 2009 ($2.467/gallon), assuming 130,500 BTUs/gallon of 

diesel fuel. Diesel price is 2009 weekly price of on-highway diesel accessed on April 22, 2010 at 

http://tonto.eia.doe.gov/dnav/pet/pet_pri_gnd_dcus_nus_a.htm; diesel energy value accessed April 22, 2010 at 

http://bioenergy.ornl.gov/papers/misc/energy_conv.html.http://www.npga.org/14a/pages/index.cfm?pageid=914

d. We monetize water impacts using the average cost of water in 2008 ($2.81/KGal) converted to 2009 dollars 

($2.87/KGal). The 2008 cost of water is taken from NUS Consulting Group, accessed on April 22, 2010 at 

http://www.marketwire.com/press-release/Average-US-Water-Costs-Increase-by-73-903477.htm. The cost was 

converted to 2009 dollars using NASA's Gross Domestic Product Deflator Inflation Calculator, accessed on April 22, 2010 

at http://cost.jsc.nasa.gov/inflateGDP.html.

e. BEES reports waste as “end of life waste.” In contrast, the datasets used in SimaPro do not report this endpoint, but this 

does not indicate that there is no solid waste output.

f. ACAA tracks quantities of CCP use in short tons, while outputs from SimaPro and BEES are given in SI units.

ESTIMATING PROGRAM LEVEL IMPACTS

In order to extrapolate the beneficial impacts presented in Exhibit ES-2 to evaluate EPA’s program-level 

efforts, two critical steps are necessary. 

 Development of defensible beneficial use scenarios that accurately identify the extent to which 

different beneficial uses are likely to increase; and

 Implementation of a well-supported attribution protocol for assigning beneficial use impacts to 

specific EPA programs. 

At this time, the data necessary to develop accurate beneficial use scenarios and to support a clear 

attribution of impacts are not sufficient to inform a detailed program analysis. In the absence of such 

data, we present a preliminary analysis of the total impacts associated with current (baseline) beneficial 

use patterns. While these impacts do not strictly reflect EPA program achievements, they represent the 

best available information on the environmental benefits of beneficially using certain CCPs, and reflect 

the impacts of all EPA, state, and industry efforts to increase CCP use to its 2008 level. The beneficial 

use impacts of current fly ash and FGD gypsum use are calculated by extrapolating the impacts identified 

in Exhibit ES-2 to the current quantity of each material beneficially used in each application. For fly ash, 

we also extrapolate the beneficial impacts associated with increasing fly ash use in concrete to 18.6 

million tons (an increase of 50 percent in the ten years since 2001). Exhibit ES-3 presents the key impacts 

of the beneficial use of CCPs extrapolated to current use quantities. Note that the impacts presented in 

Exhibit ES-3 form an upper bound estimate of the impact of EPA programs related to these materials, but 

may understate total beneficial impacts because not all materials are considered. Beneficial use of fly ash 

as a substitute for finished portland cement in concrete and FGD gypsum in wallboard accounts for only 

35 percent (21.1 million tons) of all beneficially used CCPs in 2008 (or 42 percent if excluding mining 

applications).
ES-7

EXHIBIT ES-3: EXTRAPOLATED IMPACTS OF THE BENEFICIAL US E OF CCPs

AVOIDED IMPACTS

FLY ASH IN 

CONCRETE 

EXTRAPOLATED 

TO 18.6 MILLION 

TONSa

FLY ASH IN 

CONCRETE 

EXTRAPOLATED 

TO 2008 USE 

(12.6 MILLION 

TONS)b

FGD GYPSUM IN 

WALLBAORD 

EXTAPOLATED 

TO 2008 USE 

(8.5 MILLION 

TONS)c

PARTIAL SUM OF 

2008 USE 

BENEFICIAL 

IMPACTSd

ENERGY USE

NONRENEWABLE ENERGY (MJ)e

99.7 billion 67.5 billion 11.3 billion 78.8 billion

RENEWABLE ENERGY (MJ)

f

0 0 124.2 million 124.2 million

TOTAL PRIMARY ENERGY (MJ) 99.7 billion 67.5 billion 11.4 billion 78.9 billion

TOTAL PRIMARY ENERGY (US$)g

438.8 million 297.1 million 184.9 million 482 million

WATER USE 

TOTAL WATER USE (LITERS) 12.8 billion 8.7 billion 759.3 billion 768 billion

TOTAL WATER USE (US$)

h

8.1 million 5.5 million not valued >5.5 million

GREENHOUSE GAS EMISSIONS

CO2 (MT) 18.5 million 12.5 million 0.7 million 13.2 million

METHANE (MT) 15,700 10,600 1,500 12,100

METRIC TONS CO2 EQUIVALENTi

18.8 million 12.8 million 0.7 million 13.5 million

AIR EMISSIONS

CO (MT) 25,600 17,400 300 17,700

NOx (MT) 49,900 33,800 1,300 35,100

SOx (MT) 45,600 30,900 1,600 32,500

PARTICULATES GREATER THAN PM10 (MT) 0 0 10,300 10,300

PARTICULATES LESS THAN OR EQUAL TO PM10 (MT) 143 97 4,000 4,100

PARTICULATES UNSPECIFIED (MT) 44,200 29,900 0 29,900

MERCURY (KG) 1,400 1,000 8 1,000

LEAD (KG) 0 0 300 300

WATERBORNE WASTES

SUSPENDED MATTER (KG) 9.1 million 6.2 million 0.1 million 6.3 million

BIOLOGICAL OXYGEN DEMAND (KG) 0.4 million 0.3 million 0.2 million 0.5 million

CHEMICAL OXYGEN DEMAND (KG) 0.9 million 0.6 million 0.2 million 0.8 million

COPPER (G) 0 0 17,000 17,000

MERCURY (G) 1 0 500 500

LEAD (G) 0 0 49,000 49,000

SELENIUM (G) 3 0 52,000 52,000

NON-HAZARDOUS WASTE (KG)j

0 0 0 0
ES-8

AVOIDED IMPACTS

FLY ASH IN 

CONCRETE 

EXTRAPOLATED 

TO 18.6 MILLION 

TONSa

FLY ASH IN 

CONCRETE 

EXTRAPOLATED 

TO 2008 USE 

(12.6 MILLION 

TONS)b

FGD GYPSUM IN 

WALLBAORD 

EXTAPOLATED 

TO 2008 USE 

(8.5 MILLION 

TONS)c

PARTIAL SUM OF 

2008 USE 

BENEFICIAL 

IMPACTSd

Notes:

a. We extrapolate the incremental impacts (i.e., impacts associated with use of 1 ton fly ash) in BEES to estimate impacts of 

increasing fly ash use in concrete to 18.6 million tons. 

b. We extrapolate the incremental impacts (i.e., impacts associated with use of 1 ton fly ash) to estimate the impacts of current 

beneficial use of fly ash in concrete (12.6 million tons). The current quantity of fly ash that is beneficially used as a substitute for 

finished portland cement in concrete is reported by ACAA’s 2008 CCP Survey. We multiply each of the incremental impacts 

calculated by BEES by 12.6 million tons to extrapolate these impacts to reflect current use.

c. We extrapolate the incremental impacts (i.e., impacts associated with use of 1 ton FGD gypsum) to estimate the impacts of current 

beneficial use of FGD gypsum in wallboard (8.5 million tons). The current quantity of FGD gypsum that is beneficially used as a 

substitute for mined gypsum in wallboard is reported by ACAA’s 2008 CCP Survey. We multiply each of the incremental impacts 

calculated by SimaPro by 8.5 million to extrapolate these impacts to reflect current use.

d. Calculated as the sum of the fly ash and FGD gypsum current use extrapolations.

e. Nonrenewable energy refers to energy derived from fossil fuels such as coal, natural gas and oil.

f. Renewable energy refers to energy derived from renewable sources, but BEES does not specify what sources these include.

g. We monetize energy impacts for fly ash using a price figure ($0.0044/MJ) derived from the average price of purchased energy to 

the cement manufacturing sector in 2006 ($4.36/million BTU), from Table 7.2, accessed on Nov. 16, 2010 at 

http://www.eia.doe.gov/emeu/mecs/mecs2006/2006tables.html. The cost was converted to 2009 dollars using NASA's Gross 

Domestic Product Deflator Inflation Calculator, accessed on April 22, 2010 at http://cost.jsc.nasa.gov/inflateGDP.html. We 

monetize energy impacts for FGD Gypsum using a price/MJ figure ($0.0179/MJ), derived from the average cost of diesel fuel in 

2009 ($2.467/gallon), assuming 130,500 BTUs/gallon of diesel fuel. Diesel price is 2009 weekly price of on-highway diesel accessed 

on April 22, 2010 at http://tonto.eia.doe.gov/dnav/pet/pet_pri_gnd_dcus_nus_a.htm; diesel energy value accessed April 22, 2010 

at http://bioenergy.ornl.gov/papers/misc/energy_conv.html.

h. We monetize water impacts using the average cost of water in 2008 ($2.81/KGal) converted to 2009 dollars ($2.87/KGal). The 2008 

cost of water is taken from NUS Consulting Group, accessed on April 22, 2010 at http://www.marketwire.com/pressrelease/Average-US-Water-Costs-Increase-by-73-903477.htm. The cost was converted to 2009 dollars using NASA's Gross Domestic 

Product Deflator Inflation Calculator, accessed on April 22, 2010 at http://cost.jsc.nasa.gov/inflateGDP.html.

i. We converted greenhouse gas emissions to tons of CO2 equivalent using U.S. Climate Technology Cooperation Gateway’s 

Greenhouse Gas Equivalencies Calculator accessed on Nov. 7, 2010 at http://www.epa.gov/cleanenergy/energyresources/calculator.html. This calculation only includes CO2 and methane.

j. BEES reports waste as “end of life waste.” In contrast, the EcoInvent data sets used in SimaPro do not report waste. This does not 

imply that these systems do not produce solid waste.

The results show that current beneficial use of fly ash in concrete and FGD gypsum in wallboard results 

in positive environmental impacts. The most significant impacts include energy savings and water use 

reductions, though water use reductions for FGD gypsum include turbine use and likely overstate 

consumption. Energy savings associated with the use of fly ash and FGD gypsum totals approximately 

78.9 billion megajoules of energy (or approximately $482 million in 2009 producer energy prices). Based 

on the average monthly consumption of residential electricity customers, this is enough energy to power 

roughly 2 million homes for an entire year.4 Total avoided water use including turbine use totals 

approximately 768 billion liters, but we value only the 8.7 billion liters used in the cement manufacturing 

process; this is equivalent to approximately $5.5 million in 2009 water prices, or the annual water 

consumption of 4,400 Americans.5 The extrapolated beneficial impacts also include key impacts such as 

avoided greenhouse gas (13.5 million metric tons of avoided CO2 equivalent), and avoided air emissions 

(35,100 metric tons of avoided NOx, and 32,500 metric tons of SOx).

 

4 Based on the assumption that an average residential customer uses 908 kilowatt-hours per month. EIA, “Table 5A. Residential Average Monthly 

Bill by Census Division and State, 2009” accessed Dec. 3, 2010 at www.eia.doe.gov/cneaf/electricity/esr/table5_a.xls.

5 Based on 2000 USGS per capita water use estimate of 1,430 gallons per day. Lumia et al., United States Department of the Interior, United 

States Geological Survey, Summary of Water Use in the United States, 2000. 
ES-9

This report also presents a distributional screening analysis using the EIO-LCA model that indicates 

significant avoided environmental impacts from reductions in the demand for cement or virgin gypsum 

that are distributed across several economic sectors. From the perspective of energy and air emissions, 

cement manufacturing leads to large impacts, and is in general the largest source of emissions across the 

supply chain. Reducing the amount of cement produced by beneficially reusing products can lead to large 

supply chain-wide reductions of emissions. Comparatively, the impact of the substitution of FGD 

gypsum for virgin gypsum in wallboard manufacturing is less clear, as the model was not able to 

adequately represent the wallboard sector.6

The preliminary results of this initial analysis suggest that a more detailed evaluation of the beneficial 

impacts of the beneficial use of CCPs could assist EPA in the more specific estimation of the 

achievements of the SMM program. A more detailed analysis would require:

 The development of realistic and effective beneficial use scenarios that incorporate more detailed 

descriptions of markets, beneficial uses, and policies. Realistic scenarios should reflect key 

market dynamics and limits such as distance to markets and virgin material prices, and be able to 

assess the impacts of these dynamics on the growth potential for specific beneficial uses. 

 The development of a methodology to attribute beneficial use impacts to specific EPA/SMM 

efforts and programs. A phased approach may be employed that initially assumes all impacts 

result from EPA actions. This assumption could then be refined to reflect specific strategies, 

policies, and other efforts, and link these, where possible, to specific changes in beneficial use 

practices and markets. 

 The expansion of the assessment to include additional CCPs and beneficial use applications. This 

analysis only examines the beneficial impacts of substituting fly ash for finished portland cement 

in concrete and substituting FGD gypsum for virgin gypsum in wallboard manufacturing. The 

two processes represent just 35 percent of the total beneficial use of CCPs (42 percent if 

excluding mining applications). Additional high volume applications that may be analyzed 

include: the use of fly ash as a raw feed in cement clinker; the use of boiler slag as blasting grit; 

the use of FGD gypsum in agricultural applications; and the use of various CCPs in structural fill 

and waste stabilization. In addition, the Agency may investigate the beneficial impacts of lower 

volume applications to identify those that may have potentially high incremental impacts. 

 

6 EIO-LCA models impacts at the sector level using NAICS codes but an individual NAICS code does not exist for the wallboard manufacturing sector.
1-1

CHAPTER 1: INTRODUCTION

The U.S. Environmental Protection Agency’s Office of Resource Conservation and Recovery (EPA 

ORCR) is currently considering the strategic direction of solid and hazardous waste policy. As part of 

this effort, ORCR is developing methods to evaluate the environmental, human health, and economic 

outcomes of EPA efforts to support strategic planning and program evaluation. Three important areas of 

focus in this transition are:

 Measurement of materials flow and life cycle impacts related to waste minimization and materials 

recovery and reuse, including an emphasis on “upstream” resource conservation beneficial 

impacts; 

 Documentation of the impacts of voluntary programs, including the various efforts and materials 

targeted by EPA’s Sustainable Materials Management (SMM) program (formerly known as the 

Resource Conservation Challenge (RCC));

7

and

 Development of data and approaches that can support annual performance reporting under the 

Government Performance and Results Act (GPRA) and OMB’s Performance Assessment Rating 

Tool (PART) evaluations.

As an initial step in the development of methods to assess the beneficial impacts of program benefits for 

both voluntary programs and PART, ORCR is examining the extent to which the costs and benefits of 

source reduction, reuse, and recycling may be quantified for a range of materials targeted by the SMM. 

This report examines one of the materials targeted under the SMM: coal combustion products (CCPs). 

CCPs are produced during coal-burning process at electric utilities and in industrial boilers. EPA is 

committed to the safe and protective beneficial use of CCPs, which refers to the use or substitution of 

CCPs for other products based on performance criteria. 

OVERVIEW OF REPORT

This report serves two purposes: (1) To provide an initial assessment of the market dynamics that affect 

the generation, disposal, recovery, and beneficial use of CCPs; and (2) to provide a preliminary life cycle 

inventory analysis of beneficial impacts of CCP use, including an initial estimate of the baseline 

beneficial use impacts with current (2008) CCP levels and an estimate of the beneficial impacts 

associated with increasing use of fly ash in concrete to over 18 million tons (an increase of roughly 50 

percent in ten years from a 2001 baseline beneficial use of 12.6 million tons). Ultimately, in combination 

with specific information about explicit SMM efforts, this report can be used to support the development 

and implementation of measures of program efficiency. 

 

7 The SMM is an EPA initiative that seeks to identify and encourage innovative, flexible, and protective ways to conserve natural resources and 

energy. Specifically, the SMM is a cross-Office program that assists in developing voluntary programs that promote the source reduction, reuse, 

and recycling of materials.
1-2

Organization of Report

The report proceeds in four chapters following this introduction. To provide market context, the second 

chapter characterizes the current generation and management of CCPs. The third chapter summarizes the 

current market structure for CCPs and outlines specific EPA efforts to increase their beneficial use. The 

fourth chapter uses baseline and available LCA tools to provide a preliminary life cycle inventory

analysis of the impacts of beneficial use of FGD gypsum and fly ash. The final chapter discusses the 

potential to extrapolate these beneficial use impacts and attribute them to EPA program efforts.
2-1

CHAPTER 2: BASELINE CHARACTERIZATION OF CCP 

GENERATION AND BENEFICIAL USE

Coal combustion residues (CCRs) are formed during coal-burning processes in power plants and 

industrial boilers. Coal combustion produces various forms of CCRs, which are categorized by the 

process in which they are generated. CCPs are the subset of CCRs that are targeted for beneficial reuse; 

this document uses the term broadly to describe all categories of CCRs in which some portion have been 

beneficially used.

The coal-fired power industry is the largest generator of CCPs. Other industries, such as commercial 

boilers and mineral and grain processors that use coal as a fuel source also produce small quantities of 

CCPs. Because these other industries generate such small quantities of CCPs relative to the coal-fired 

electric power industry, this report focuses solely on the coal-fired electric power industry.8 

CCPs are categorized by the process in which they are generated, which varies by plant. CCPs include the 

following materials:

 Fly ash. Exhaust gases leaving the combustion chamber of a power plant entrain fly ash particles 

during the coal combustion process. To prevent fly ash from entering the atmosphere, power 

plants use various collection devices to remove it from the gases that are leaving the stack. Fly 

ash is the finest of coal ash particles. The American Society for Testing and Material (ASTM) 

identifies two classes of fly ash suitable for beneficial use based on chemical composition. Class 

F fly ash results from the burning of anthracite or bituminous coal, while Class C fly ash results 

from the burning of lignite or subbituminous coal. 

 Bottom ash. With grain sizes ranging from fine sand to fine gravel, bottom ash is coarser than 

fly ash. Utilities collect bottom ash from the floor of coal burning furnaces used in the generation 

of steam, the production of electric power, or both. The physical characteristics of the product 

generated depend on the characteristics of the furnace.

 Flue Gas Desulphurization (FGD) material. FGD material results from the flue gas 

desulphurization scrubbing process that transforms gaseous SO2, released during coal 

combustion, to sulfur compounds. Coal-fired power plants employ either a wet or dry scrubbing 

method to remove SO2 from their emissions. The final by-product of wet scrubbing is primarily 

FGD gypsum, although small amounts of other materials (e.g., ash, metals) are also produced.9In 

this report, we refer to these other materials as “other FGD wet material.” The dry method 

produces by-products that consist of mainly calcium sulfite, fly ash, portlandite, and calcite. 

Collectively, we refer to these materials as “FGD dry material.”10 All three materials, FGD 

gypsum, other FGD wet scrubber material, and FGD dry scrubber material, can be used in a 

number of beneficial use applications.

 

8 As of the writing of this report, we were unable to locate data estimating the quantities of CCPs attributable only to the electric power industry; 

however, since the coal power industry consumes approximately 92 percent of all U.S. coal, it is reasonable to assume that significant majority of 

CCPs result from the burning of coal at coal-fired power plants. EIA, 2007, “U.S. Coal Consumption by End-Use Sector,” 

http://www.eia.doe.gov/cneaf/coal/quarterly/html/t28p01p1.html.

9 FGD gypsum has a very similar chemical structure (calcium dihydrate) to naturally occurring gypsum (calcium sulfate).

10 Electric Power Research Institute, 1999. Environmental Focus: Flue Gas Desulfurization By-Products. BR-114239
2-2

 Boiler Slag. Boiler slag consists of molten ash collected at the base of cyclone boilers. Facilities 

cool boiler slag with water, which then shatters into black, angular pieces that have a smooth 

appearance. 

 Fluidized Bed Combustion (FBC) ash (not pictured in Exhibit 2-1). A fluidized bed

combustion boiler, a type of coal boiler that combines the coal combustion and flue gas 

desulphurization processes within a single furnace, generates FBC ash. FBC ash is rich in lime 

and sulfur.

 Cenospheres. Generated as a component of fly ash in high temperature coal combustion, 

cenospheres consist of extremely small, lightweight, inert, hollow spheres comprised largely of 

silica and alumina that are filled with low-pressure gases.11 When fly ash is disposed in 

settlement lagoons, cenospheres can be collected on the surface where they can be skimmed for 

use in manufacturing processes.

At a typical coal-fired power plant, coal combustion generates CCPs during several phases of the process. 

Exhibit 2-1 illustrates the collection of several types of CCPs. As depicted below, facilities remove 

bottom ash and boiler slag from the base of the furnace. Fly ash accumulates in the particulate collection 

device, while FGD material collects in the SO2 control device.

EXHIBIT 2-1: COAL COMBUSTION PROCESS AT A COAL-FIRED POWER PLANT

Source: Energy Information Administration, accessed at www.eia.doe.gov.

 

11 Cenospheres range in size from 20 to 5000 microns.

FLY ASH & CENOSPHERES

FGD MATERIAL

BOTTOM ASH/ BOILER SLAG REMOVAL
2-3

CURRENT QUANTITIES OF CCPS GENERATED AND MANAGED

In 2008, the coal-fueled electric power industry generated approximately 136 million short tons of CCPs. 

Of these, the industry disposed of approximately 75 million short tons to landfills, while beneficially 

using approximately 61 million short tons in products.12 Exhibit 2-2, below, presents the current 

quantities of CCPs generated and managed, in the context of other materials targeted by the SMM. 

Except for construction and demolition material, the U.S. generates larger quantities of CCPs than other 

types of industrial waste and municipal solid waste (MSW).

EXHIBIT 2-2: SMM MATERIAL BY QUANTITIY

MATERIALa

QUANTITY 

GENERATED 

(MILLION SHORT 

TONS)

QUANTITY 

RECOVERED/

BENEFICIALLY USEDb

(MILLION SHORT 

TONS)

QUANTITY 

DISPOSED 

(MILLION SHORT 

TONS) YEAR

C&D Material1 331 214c 118 2003

CCPs2 136 61 75 2008

Paper and Paperboard3 77 43 34 2008

Packaging3 77 34 33 2008

Organics3 65 22 43 2008

Foundry Sand4, d 9.4 2.6 6.8 2006

Chemicals5 0.04 NA NA 2003

Notes:

a. Under the RCC (now SMM) 2005 Action Plan, increases in the rate of MSW recovery and reduction of priority and toxic 

chemicals are also targeted. We have included these material streams in this exhibit even though they are not targeted 

specifically for beneficial use.

b. The figures shown for paper and paperboard, packaging, and organics are the quantities recovered from the MSW stream. 

The figures shown for C&D debris, CCPs, and foundry sand are quantities that are beneficially used. The figure for CCPs 

includes use in mining applications, which EPA considers disposal. EPA, 2010, “Hazardous and Solid Waste Management 

System; Identification and Listing of Special Wastes; Disposal of Coal Combustion Residuals From Electric Utilities; Proposed

Rule,” 75 FR 118 (June 21, 2010), p. 35148.

c. A Construction Materials Recycling Association member survey estimates that approximately 270 million tons of C&D material 

including asphalt and concrete from roads, bridge-related infrastructure, and land clearing debris was recovered in 2004. 

d. The foundry sand quantities shown are based on the AFS survey conducted from 2005 to 2007. The quantity disposed includes 

sands used as landfill cover.

Sources:

1. US EPA, “Characterization of Building-Related Construction and Demolition Debris in the United States” and 

“Characterization of Road-related Construction and Demolition Debris in the United States,” 2005. (Note that these 

documents are preliminary and are currently undergoing peer-review).

2. ACAA, “2008 Coal Combustion Product (CCP) Production and Use Survey,” accessed Oct. 18, 2010, 

http://acaa.affiniscape.com/associations/8003/files/2008_ACAA_CCP_Survey_Report_FINAL_100509.pdf. 

3. EPA, 2009, “Municipal Solid Waste Generation, Recycling, and Disposal in the United States: Facts and Figures for 2008,” 

accessed on Oct. 18, 2010 at http://www.epa.gov/wastes/nonhaz/municipal/pubs/msw2008data.pdf.

4. American Foundry Society (AFS), 2007, “Foundry Industry Benchmarking Survey.” 

5. US EPA, “Draft National Priority Trends Report (1999-2003) Fall 2005,” as reported in the NPEP GPRA 2008 database of TRI 

data from 1998-2003.

 

12 This figure includes CCPs used in mining applications, which EPA may consider a “large-scale filling operation” and therefore consider disposal. 

EPA, 2010, “Hazardous and Solid Waste Management System; Identification and Listing of Special Wastes; Disposal of Coal Combustion Residuals 

From Electric Utilities; Proposed Rule,” 75 FR 118 (June 21, 2010), p. 35148.
2-4

The American Coal Ash Association (ACAA), a trade association whose purpose is to advance the 

beneficial use of CCPs, conducts an annual survey of coal-fired electric plants to collect data on the 

production, disposal, and use of CCPs in the U.S.13 Exhibit 2-3 summarizes the 2008 survey on 

generation, disposal, and beneficial use of various CCP categories.

EXHIBIT 2-3: SUMMARY OF CCP GENERATION AND MANAGEMENT IN 2008

PRODUCT

CCPS 

GENERATED

(MILLION SHORT 

TONS)

BENEFICIALLY

USED

(MILLION SHORT 

TONS)B

PERCENT 

USED

QUANTITY 

DISPOSED

(MILLION 

SHORT TONS)a

PERCENT 

DISPOSED

Fly Ash 72.45 30.14 42% 42.31 58%

Flue Gas Desulfurization (FGD) 

Material 33.67 11.82 35% 21.85 65%

 FGD Gypsum 17.75 10.65 60% 7.10 40%

 FGD Material Wet Scrubbers 12.98 0.69 5% 12.30 95%

 FGD Material Dry Scrubbers 1.40 0.35 25% 1.05 75%

 FGD Other 1.54 0.14 9% 1.40 91%

Bottom Ash 18.43 8.08 44% 10.36 56%

Boiler Slag 2.03 1.69 83% 0.34 17%

Fluidized Bed Combustion (FBC) 

Ash 9.49 8.86 93% 0.62 7%

Cenospheresc Not available 0.005 Not available Not available Not available

Total CCPs 136.07 60.59 45% 75.48 55%

Notes:

a. Calculated by subtracting quantity beneficially used from quantity generated.

b. These figures include use in mining applications, which EPA appears to consider disposal. EPA, 2010, “Hazardous and Solid 

Waste Management System; Identification and Listing of Special Wastes; Disposal of Coal Combustion Residuals From Electric 

Utilities; Proposed Rule,” 75 FR 118 (June 21, 2010), p. 35148.

c. The ACAA’s “CCP Production and Use Survey” does not report total generation or disposal quantities for cenospheres, only 

sales. 

Source:

ACAA, “2008 Coal Combustion Product (CCP) Production and Use Survey,” accessed Oct. 18, 2010, 

http://acaa.affiniscape.com/associations/8003/files/2008_ACAA_CCP_Survey_Report_FINAL_100509.pdf. 

 

13 The ACAA survey is administered to both ACAA members and non-members. ACAA members account for approximately 40 percent of private 

power generation. Not all survey recipients complete the survey each year. ACAA extrapolates survey respondent data to the entire coal-fired 

electricity generation industry. To the extent that other coal-burning industries are not represented in the ACAA sample, the survey may 

underestimate the quantity of CCPs generated and/or beneficially used. 
2-5

Exhibit 2-3 illustrates several important aspects of the generation, beneficial use, and disposal of CPPs:

 Of reported materials, fly ash constitutes the largest proportion (53 percent) of CCP materials 

generated in 2008. FGD material follows at 25 percent. 14 Bottom ash, boiler slag and FBC ash 

collectively comprise the remaining 22 percent of CCPs generated in 2008.

 Boiler slag, FGD gypsum, and FBC ash have the highest percentage of beneficial use. However, 

FBC ash is used mainly in mining applications, which EPA may not consider a beneficial use.15

 Fly ash, FGD material other than FGD gypsum, and bottom ash have the highest disposal rates.

In addition to quantities of fly ash reported in the ACAA survey, stockpiles may provide another potential 

source of fly ash for certain beneficial uses. Industry sources estimate that between 100 million and 500 

million tons of fly ash have accumulated in U.S. landfills since the 1920s, when disposal of fly ash in 

landfills began.16, 17 

Beneficial Use Options

The chemical and physical properties of CCPs allow for their use in a wide range of products. CCPs may 

be used as a component of various building materials (i.e., as a replacement for portland cement in 

concrete) or as a direct replacement for other virgin materials such as sand, gravel, or gypsum. The 

physical properties of CCPs make them especially useful for construction and industrial materials. Size, 

shape, and chemical composition determine the suitability of specific material flows for beneficial use. 

Higher value applications, such as use in cement or concrete products, require comparatively stringent 

specifications (in terms of size, shape and chemical composition), whereas lower value uses, such as 

structural or mining fills, can accept more variable materials. For this reason, EPA has noted that lower 

technology applications that require large volumes of CCPs may present the greatest potential for 

expanded beneficial use.18 

Exhibit 2-4 summarizes the most common beneficial uses for CCPs. This table excludes cenospheres as 

data on the primary beneficial uses of this material are not available.

 

14 The quantity of cenospheres generated is not reported by ACAA so the 58 percent estimate could be higher if cenospheres were included.

15 EPA, 2010, “Hazardous and Solid Waste Management System; Identification and Listing of Special Wastes; Disposal of Coal Combustion Residuals 

From Electric Utilities; Proposed Rule,” 75 FR 118 (June 21, 2010), p. 35148.

16 Personal communications with Dave Goss, ACAA and Tom Janson, WE Energies, November 27, 2006.

17 The quantity of stockpiled fly ash that is available for beneficial use is unclear. The chemical composition of fly ash varies depending on the type 

of coal used, and only two types of fly ash--class C fly ash and class F fly ash—meet the ASTM technical requirements for concrete. It is unclear 

how much of the estimated 100-500 million tons of stockpiled fly ash falls into one of these classes. In addition, exposure to moisture or 

contamination in the stockpiles can limit the beneficial use options of Class C ash, though, this is not a concern with Class F ash. Information on 

these standards can be found at http://www.astm.org.

18 EPA. 1999. “Report to Congress: Wastes from the Combustion of Fossil Fuels.” Vol. II. EPA-530-R-99-010, March 1999.
2-6

EXHIBIT 2-4: COMMON BENEFICIAL US ES FOR CCPS

CCP BENEFICIAL USE 

Fly Ash

Concrete: Concrete consists of a mixture of approximately 25% fine aggregate (sand), 45% gravel, 

15% portland cement, and 15% water. Class C and class F fly ash can replace a percentage of the 

portland cement component of concrete. Fly ash contributes to enhanced concrete strength and 

durability, and is typically less expensive than portland cement.

Cement clinker: Clinker is an intermediary product of the portland cement manufacturing process. 

Clinker is formed when a raw mix of limestone, clay, bauxite, iron ore and quartz is heated in a 

kilm at high temperatures. Fly ash can be blended with limestone or shale and fed into the kiln to 

make clinker, which is then ground into portland cement. 

Structural fill: Structural fill is an engineered material used to raise or change the surface contour 

of an area and to provide ground support beneath building foundations. It can also be used to form 

embankments. Depending on the soil type, fly ash can replace a percentage (generally 50 percent) 

of virgin rock, dirt, sand or gravel in structural fill.

Waste stabilization: Fly ash can be used in place of portland cement, cement kiln dust, or lime to 

solidify and harden wet or liquid waste before it is landfilled. Class C fly ash hardens by itself in 

contact with moisture, but class F fly ash must be mixed with another hardening agent, such as 

portland cement, in order to be used in waste stabilization.

FGD 

Gypsum

Wallboard: Gypsum wallboard (drywall) is an interior finish in building construction. Wallboard is a 

layer of gypsum stucco sandwiched between two sheets of heavy paper. FGD gypsum can replace 

100 percent of virgin gypsum in wallboard after excess moisture is removed.

Agricultural soil amendment: FGD gypsum can be used to replace liming agents and to provide 

certain nutrients as an agricultural soil amendment for specific soil and crop types.

Cement additive: In the production of portland cement, clinker is blended with a small amount of 

gypsum prior to grinding into finished portland cement. FGD gypsum can be used to offset virgin 

gypsum in cement manufacture.

Bottom Ash

Structural fill: Structural fill is an engineered material used to raise or change the surface contour 

of an area and to provide ground support beneath building foundations. It can also be used to form 

embankments. Bottom ash can be used to offset virgin sand and gravel in structural fill.

Road base: A road base is a foundation layer underlying a pavement and overlaying a subgrade of 

natural soil or embankment fill material. It protects the underlying soil from the detrimental 

effects of weather conditions and from the stresses and strains induced by traffic loads. Bottom 

ash can be used to offset virgin sand or gravel in road base.

Concrete: Bottom ash can be used as a coarse aggregate for concrete blocks, with its porous 

nature often qualifying the product for lightweight classification.

Boiler Slag

Blasting Grit: Blasting grit is an industrial abrasive used to shape, cut, sharpen, or finish a variety 

of other surfaces and materials. Boiler slag can be used as a replacement for other slags or virgin 

sand as blasting grit.

Structural fill: Structural fill is an engineered material used to raise or change the surface contour 

of an area and to provide ground support beneath building foundations. It can also be used to form 

embankments. Boiler slag is occasionally used to offset virgin sand and gravel in structural fill.

FBC Ash

Mining applications: FBC ash can be placed into abandoned mines during reclamation to neutralize 

the acidity of mine drainage. EPA considers large fill operations to be disposal, and so would not

likely consider mining applications a beneficial use, though it is tracked by ACAA.

Exhibit 2-5, below, illustrates the quantities of CCPs being used in the most common beneficial use 

applications. The applications highlighted in the exhibit represent 90 percent of the current use of 
2-7

CCPs.19 We include an expanded version of this table, which details a more inclusive set of CCP 

beneficial use applications, in Appendix A. 

EXHIBIT 2-5: KEY BENEFICIAL USES FOR CCPS IN 2008 (MILLION SHORT TONS)

APPLICATION 

(INDUSTRY)

COAL 

FLY ASH

BOTTOM 

ASH

FGD 

GYPSUM

FGD MATERIAL 

WET SCRUBBERS

FGD MATERIAL 

DRY SCRUBBERS

FGD 

OTHER

BOILER 

SLAG

FBC 

ASH TOTAL

Concretea

(Construction) 12.59 0.72 0.68 0 0.02 0 0 0.004 14.02

Structural fillb

(Construction) 8.01 3.00 0 0 0.13 0.11 0.18 0.08 11.50

Mining 

applicationsc 0.96 0.06 0 0.69 0.11 0 0.003 8.64 10.47

Wallboardd 

(Construction) 0 0 8.53 0 0 0 0 0 8.53

Raw feed for 

cement clinkere

(Construction) 3.17 0.61 0.41 0 0 0 0 0 4.20

Waste stabilizationf

(Waste Mgmt) 2.92 0.08 0.74 0 0.001 0.03 0 0 3.78

Road baseg 1.03 0.77 0 0 0 0 0 0.01 1.80

Total - Key Uses 28.69 5.24 10.37 1 0.26 0.14 0.18 8.73 54.30

Total - Other 

Usesh

1.45 2.83 0.29 0.00 0.08 0.00 1.51 0.13 6.29

TOTAL - ALL USES 30.14 8.08 10.65 0.69 0.35 0.14 1.69 8.86 60.59

2008 QUANTITY 

GENERATED 72.45 18.43 17.75 12.98 1.40 1.54 2.03 9.49 136.07

CCP UTILIZATION 

RATEg 42% 44% 60% 5% 25% 9% 83% 93% 45%

Notes:

a. CCPs are frequently used as a replacement for a portion of portland cement in the manufacture of concrete.

b. Structural fill is an engineered material that is used to raise or change the surface contour of an area and to provide ground 

support beneath highway roadbeds, pavements and building foundations. It can also be used to form embankments.

c. FBC ash and other CCPs can be used in mine reclamation to refill mines and to help mitigate acid mine drainage. EPA considers 

large fill operations such as this use to be disposal and not a beneficial use (75 FR 118 p. 35148).

d. FGD gypsum is used as a substitute for virgin gypsum in wallboard manufacturing.

e. CCPs can be blended with limestone or shale in the cement kiln to make clinker, which is then ground into Portland cement.

f. The chemical properties of CCPs make them effective stabilizers of biosolids (i.e., sludge from municipal waste water treatment).

g. Coal ash is used as in ingredient in road base and sub-base.

h. Presents quantities beneficially used in minor applications not included in this exhibit, but listed in Appendix A.

i. CCP utilization rates reflect all use applications, some of which are omitted from this table but are included in Appendix A.

Utilization rates are calculated by dividing the total quantity used by the total quantity generated.

Sources: 

1. ACAA, “2008 Coal Combustion Product (CCP) Production and Use Survey,” accessed Oct. 18, 2010 at 

 http://acaa.affiniscape.com/associations/8003/files/2008_ACAA_CCP_Survey_Report_FINAL_100509.pdf. 

2. Western Region Ash Group, “Applications and Competing Materials, Coal Combustion Byproducts,” accessed at 

 http://www.wrashg.org/compmat.htm.

 

19 Relatively minor applications comprise the remaining 10 percent of CCP beneficial uses. These applications include uses such as blasting grit, soil 

modification and stabilization, and as flowable fill.
2-8

Exhibit 2-5 illustrates several important aspects regarding the beneficial use options for CCPs:

 Concrete, structural fill, mining applications, and wallboard comprise the highest volume 

beneficial uses of CCPs. 

 The use of fly ash as a pozzolanic binder in concrete represents the largest single beneficial use 

application of a CCP material.20 Fly ash can substitute for finished portland cement in concrete 

and can be a valuable additive to concrete mixtures that enhances the strength, durability, and 

workability of the concrete product.21

 FBC ash is used in mine reclamation to fill mines and to help prevent acid mine drainage.22 This 

represents the second largest application of a CCP material as identified by ACAA, and yields a 

high use rate for FBC ash of 93 percent. However, EPA considers large fill operations to be 

disposal, and therefore would not likely consider mining applications to be a beneficial use.23

 FGD gypsum serves as a substitute for virgin gypsum in wallboard construction. This high-value 

use represents the third largest use of a CCP material by volume.

 Although one of the smaller material streams, facilities beneficially use boiler slag in blasting grit 

(not shown on this exhibit) and structural fill, yielding a high use rate of 83 percent. Boiler slag 

is in high demand for beneficial use. Boiler slag particles are highly uniform in size, hard, and 

durable. In addition, its permanent black color makes it ideal for asphalt applications and aids in 

melting snow.

24

The results of the 2008 ACAA survey compared with the previous surveys in 2005, 2006 and 2007 show 

an overall increase in the CCP utilization rate in recent years. In 2005, the beneficial use rate was 40.3 

percent, and by 2008 it was 44.6 percent, with little deviation from the trend in between. However, both 

generation and beneficial use of CCPs increased during this period, and the amount disposed actually 

increased slightly from 73.5 million tons in 2005 to 75.4 million tons in 2008. 25 The most significant 

changes within categories are boiler slag, which decreased in its use rate by 13 percentage points; and 

FGD gypsum and FGD material from dry scrubbers, which increased their beneficial use rates by 17 and 

14 percentage points, respectively. 26, 27

 

20 Fly ash is technically a pozzolanic, not a cementitious material. A cementitious material, such as portland cement, is one that hardens when 

mixed with water. A pozzolanic material will also harden with water but only after activation with an alkaline substance such as lime. The 

combination of portland cement and water in concrete mixtures creates two products: a durable binder that “glues” concrete aggregates together 

and free lime. Fly ash reacts with this free lime to create more of the desirable binder.

21 Personal communication with Tom Pyle, Caltrans, November 2006.

22 Schueck, Joseph et al, 2001, “The Use of FBC Ash for Alkaline Addition at Surface Coal Mines,” 2002 International Ash Utilization Symposium, 

accessed Nov. 19, 2010 at http://www.flyash.info/2001/mining1/49schue.pdf. 

23 EPA, 2010, “Hazardous and Solid Waste Management System; Identification and Listing of Special Wastes; Disposal of Coal Combustion Residuals 

From Electric Utilities; Proposed Rule,” 75 FR 118 (June 21, 2010), p. 35148.

24 EPA, “Boiler Slag,” accessed Nov. 18, 2010 at http://www.epa.gov/osw/conserve/rrr/imr/ccps/boilslag.htm.

25 Though, part of the increase in beneficial use figures was from an increase of FBC ash in mining applications, which EPA considers disposal.

 EPA, 2010, “Hazardous and Solid Waste Management System; Identification and Listing of Special Wastes; Disposal of Coal Combustion Residuals 

From Electric Utilities; Proposed Rule,” 75 FR 118 (June 21, 2010), p. 35148.

26 ACAA, Coal Combustion Product (CCP) Production and Use Surveys for 2005 to 2008, accessed Oct. 18, 2010 at 

http://acaa.affiniscape.com/displaycommon.cfm?an=1&subarticlenbr=3.

27 Use of boiler slag is decreasing in part because the supply of boiler slag is declining as the types of boilers that produce boiler slag are phased 

out. EPA, “Boiler Slag,” accessed at http://www.epa.gov/osw/conserve/rrr/imr/ccps/boilslag.htm.
3-1

CHAPTER 3: MARKET STRUCTURE FOR BENEFICIAL USE OF CCPs

Understanding the factors that affect beneficial use of CCPs requires consideration of the underlying 

markets affecting its generation and management. The CCP market includes three market segments: (1) 

coal-fired utilities, (2) intermediaries: CCP marketers and consultants, and (3) end-users. In addition, 

state regulators determine the extent to which CCPs can be beneficially used by defining the regulatory 

context in which these actors operate. This chapter considers the factors affecting beneficial use decisions 

among these groups participating in the marketplace. We then present a discussion of opportunities for 

growth in the selected CCP markets, along with a more specific illustration using two common beneficial 

applications. Finally, we discuss our efforts to improve market conditions for CCPs.

Three main challenges exist in developing the beneficial use market for CCPs. First, because CCPs are a 

heavy material to transport, the distance between the location of the coal-fired utility generating the CCPs 

and the potential end-user is a driving factor in determining whether the CCPs will be beneficially used in 

a project. Another difficulty in developing the beneficial use market is the capacity for individual coalfired utilities to provide a quantity of high quality CCPs sufficient to meet end-users’ demands. The 

ability of end-users to obtain enough CCPs for their purposes is an important consideration in estimating 

and sustaining demand for CCPs. Finally, as noted above, the variability in use options across states 

poses a challenge to both coal-burning plants and end-users in trying to determine applicable beneficial 

use options for CCPs. 

COAL-FIRED UTILITY PRACTICES: CCP SUPPLY

The coal-fired power industry is the largest generator of CCPs in the United States. As noted previously, 

other industries that use coal as a fuel source in commercial or industrial boilers (e.g., mineral and grain 

processors) also produce small quantities of CCPs. Coal-generated electricity supplies roughly half of 

electricity consumed in the United States.28 In its 2010 Annual Energy Outlook middle-range scenario, 

the EIA projects that electricity demand will increase by 30 percent between 2008 and 2035, and that the 

share of electricity generation supplied by coal will reach 44 percent, down from 48 percent in 2008. 

Since coal will continue to be an important fuel source, it is likely that the quantity of CCPs produced and 

available for beneficial use will also increase.29

An estimated 495 coal-fired electric utility plants currently operate in the U.S.30 Exhibit 3-1 shows the 

geographic distribution of coal consumption by electric power plants across the U.S. Coal consumption 

by power plants is greatest in the East North Central region of the U.S., but consumption remains 

relatively high throughout the entire Central and Southern United States. Coal consumption is low in the 

contiguous and noncontiguous Pacific regions of the U.S. and in New England. CCP generation closely 

approximates the geographic distribution of coal consumption across the U.S., but is not directly 

proportional to coal consumption. The composition of coal varies regionally in the U.S. For example, the 

non-combustible portion (commonly referred to as “ash”) of Western bituminous coal is higher than that 

of Western sub-bituminous coal (roughly 10 to 15 percent and four to six percent ash, respectively). Coal 

with a higher non-combustible ash content will yield greater quantities of CCPs when combusted. 

 

28 EIA, 2010, “Net Generation by Energy Source: Total (All Sectors),” accessed October 25, 2010 at 

http://www.eia.doe.gov/cneaf/electricity/epm/table1_1.html.

29 EIA, 2010, “Annual Energy Outlook 2010 with Projections to 2035: Electricity Demand,” accessed October 25, 2010 at 

http://www.eia.doe.gov/oiaf/aeo/electricity.html. 

30 EPA, 2010, “Regulatory Impact Analysis for EPA’s Proposed RCRA Regulation Of Coal Combustion Residues (CCR) Generated by the Electric Utility 

Industry,” EPA-HQ-RCRA-2009-0640-0003.
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EXHIBIT 3-1: ELECTRIC POWER SECTO R CONSUMPTION OF COAL IN 2009, BY CENSUS REGION 

(MILLION SHORT TONS AND PERCENT CHANGE FROM 2008) 

Source: Energy Information Administration, 2010, “Figure 3. Electric Power Sector Consumption of Coal by Census Region, 

2009,” accessed Oct. 31, 2010 at http://www.eia.doe.gov/cneaf/coal/page/special/fig3.html.

Several factors influence a utility’s decision to supply CCPs for beneficial use. Economic factors are the 

primary consideration and include:

 Landfill disposal costs. For many utilities, the sale of CCPs for beneficial use is a means of 

reducing operating costs through avoidance of landfill tipping fees. In order for beneficial use of 

CCPs to be competitive, the cost of reselling CCPs, minus revenue from the sale, must be less 

than the cost of landfill disposal. Landfill tipping fees vary regionally but range from $5 per ton 

to $45 per ton.31 Avoiding landfill disposal costs may be a significant incentive for a utility to 

engage in beneficial use.

 Revenue from sale. Depending on the type of CCP, an electric utility may or may not receive 

revenue for its ash. For some CCP types, marketers will accept ash as a service to the plant 

(allowing the plant to avoid disposal costs) but do not pay for the ash. For other CCP types, 

especially fly ash, boiler slag and cenospheres, the revenue received can be a significant incentive 

for a utility to market its ash.32

 Transport costs. CCPs are heavy materials, which makes transport over long distances 

expensive. Transport distance between the utility and the nearest landfill or end-user is a 

significant determinant in the management of CCPs.

 

31 Personal communication with Dave Goss, American Coal Ash Association, April 2006.

32 Personal communication with Dave Goss, American Coal Ash Association, May 2006.
3-3

 Processing costs. Approximately 90 to 95 percent of CCPs do not require processing prior to 

beneficial use. However, higher value applications that require specialized CCP products may 

require processing to meet material specifications.

 Storage costs. In many parts of the country, the production of coal ash is high during both the 

coldest and hottest months of the year when people are heating and cooling their homes, offices 

and schools. However, the winter season is often the slowest period for construction and other 

applications that beneficially use the fly ash. As a result, it is necessary to store CCPs until they 

can be utilized. Typically, domes are inflated adjacent to boilers for the CCP collection. The cost 

of storing fly ash or other CCPs during the winter months may be a deterrent to beneficial use by 

a utility. 

 Marketing costs. In order to attract buyers of CCPs, a marketer must devote financial resources 

to marketing their specific product(s) for beneficial use. Some utilities market their CCPs 

directly to end-users, but others pay a third party marketer or broker to negotiate CCP sales. 

In the end, a generator’s decision to make CCPs available for beneficial use rather than disposal is a result 

of a confluence of all the above factors, as well as non-economic factors such as access to information 

about permissible applications and availability of technical assistance. Depending on the circumstances, a 

coal-fired utility may weigh certain factors more heavily than others. For example, since off-site disposal 

and transport to a marketer or end-user both require hauling, total transport distance to the off-site facility 

is an important consideration. If the off-site disposal facility is closer, then a generator may opt to send 

its CCPs to the landfill instead of to the marketer or end-user. However, if the avoided disposal costs 

from the marketing arrangement are higher than the cost of offsite disposal, then avoided costs may be 

enough to offset the additional cost to transport the materials to the marketer or end-user. In addition, a 

coal-fired utility may be more willing to absorb higher costs (of transport, marketing, etc.) for highervalue materials and uses for which it can charge a higher premium (e.g. fly ash as a portland cement 

substitute in concrete).33

INTERMEDIARIES

Many coal-fired electric generators market their CCPs through a third-party marketer instead of selling 

directly to the end-user. In these cases, a utility perceives an efficiency in outsourcing the marketing of 

its CCPs. Marketers typically accept all of a generator’s CCPs as a service to the company, sell the 

marketable portion, and dispose of the portion that is not salable. The marketer typically bears the cost of 

hauling CCPs from the utility and incorporates this cost into the sale price.

END-USERS AND PURCHASERS: CCP DEMAND

Several factors influence an end-user’s decision to use CCPs in a product, including:

 Price of CCPs relative to the price of virgin materials.34 If the price of a virgin material is less 

than the price of CCPs (which will reflect cost factors such as transport distance, processing and 

storage costs), end-users will generally purchase virgin materials. In areas where virgin materials 

are abundant and inexpensive, CCPs may not be economically viable. Exhibit 3-2 shows the 

 

33 Note that the transfer of CCPs from generators to users may lead to potential cost savings for the generators. It may be possible for generators 

to shift liability (and related costs) associated with CCPs to users of the product. The law on this matter is not well-defined and needs to be 

clarified to determine the magnitude of any potential cost savings.

34 Note that the “price” of CCPs represents how much an end-user would pay for the product. 
3-4

typical price ranges for CCPs used in various applications relative to the virgin materials they 

replace.

EXHIBIT 3-2: SAMPLE CCP AND VIRGIN MATERIAL PRICES FO R CCP APPLICATIONS

VIRGIN MATERIAL

2008 AVG 

PRICE, (PER 

TON, FREE ON 

BOARD)a 2009 PRICEb CCP SUBSTITUTE

2003 AVG 

PRICE, (PER 

TON, FREE ON 

BOARD)a 2009 PRICEb

Portland cement $93.44 $95.34

Concrete quality fly 

ash $20 to $45 $22.01 to $49.53

Boiler slag Not available

Virgin aggregate for fill $4.08 $4.16 Fly ash for flowable fill $1 and up $1.10 and up

Virgin aggregate for road 

base $5.79 $5.91 Bottom ash or fly ash for road base $4 to $8 $4.40 to $8.81

Lime for soil stabilization

(Hydrated lime) $97.30 $99.28 Fly ash for soil 

stabilization $10 to $20 $11.01 to $22.01

Lime for waste 

stabilization (Quicklime) $81.60 $83.26 Fly ash for waste stabilization $15 to $25 $16.51 to $27.52

Virgin aggregate for snow 

and ice control $6.25 $6.38 Bottom ash for snow and ice control $3 to $6 $3.30 to $6.60

Gypsum for wallboard

(calcined) $38.68 $39.47 FGD Gypsum $0 - $8.00 $0 – $8.81

a. Virgin material prices are reported by USGS while CCP prices are provided by ACAA. This price data represents the 

best available information, and should be cross-compared with caution, as the data may not capture all factors driving 

price variability. “Free on Board” indicates that the supplier pays the shipping costs (and usually the insurance costs) 

from the point of manufacture to a specified destination, at which point the buyer takes responsibility. Virgin 

material prices for portland cement, virgin aggregate, and gypsum were originally per metric ton; we converted to 

price per short ton.

b. The cost was converted to 2009 dollars using NASA's Gross Domestic Product Deflator Inflation Calculator, accessed on 

April 22, 2010 at http://cost.jsc.nasa.gov/inflateGDP.html.

Sources:

1. USGS, 2010, “Mineral Commodity Summaries: Cement, 2010,” accessed Nov. 20, 2010 at 

http://minerals.usgs.gov/minerals/pubs/commodity/cement/mcs-2010-cemen.pdf

2. USGS, 2010, “2008 Minerals Yearbook: Sand and Gravel, Construction [Advance Release],” accessed Nov. 20, 2010 at 

http://minerals.usgs.gov/minerals/pubs/commodity/sand_&_gravel_construction/myb1-2008-sandc.pdf.

3. USGS, 2010, “2008 Minerals Yearbook: Lime [Advance Release],” accessed Nov. 20, 2010 at 

http://minerals.usgs.gov/minerals/pubs/commodity/lime/myb1-2008-lime.pdf.

4. USGS, 2010, “2008 Minerals Yearbook: Gypsum [Advance Release],” accessed Nov. 20, 2010 at 

http://minerals.usgs.gov/minerals/pubs/commodity/gypsum/myb1-2008-gypsu.pdf.

5. ACAA (American Coal Ash Association), 2008, “Frequently Asked Questions,” accessed Nov. 19, 2010 at 

http://acaa.affiniscape.com/displaycommon.cfm?an=1&subarticlenbr=5.

6. Miller, Cheri. Gypsum Parameters. Presentation at WOCA Short Course: "Strategies for Development of FGD Gypsum 

Resources."

 Technical fit between CCPs and use application. CCPs have varying physical and chemical 

characteristics due to differences in coal types, combustion processes, air pollution control 

technologies, and CCP management practices at individual power plants. To be beneficially used 

in a particular application, the chemical and physical properties of the CCP must align with the 

engineering requirements of that application. For example, high carbon content or the presence 

of air emission additives may render some CCPs unsuitable for some use applications.
3-5

 Sufficient quantities of CCPs. Some beneficial use applications require larger volumes of CCPs 

than are typically produced at a single power plant. Where demand for CCPs is greater than the 

supply generated by a single plant, the end-user may need to purchase CCPs from multiple 

suppliers; this can increase transaction costs.

 State Regulations. Regulations governing beneficial use of CCPs vary by state. In many states, 

beneficial use of CCPs must be approved on a project-by-project basis. Currently, public and 

environmental health considerations drive state regulatory decisions concerning beneficial use of 

CCPs in end-use applications.35,36

 Incomplete science. In the absence of definitive data on all health and environmental risks 

associated with the beneficial use of CCPs, some states have chosen to limit the use of CCPs in 

building materials. For example, EPA research has found that CCPs may release small quantities 

of mercury to the ambient air during use in certain industrial processes37 Noting this research, 

States have questioned the safety of using fly ash in cement to be used in schools.38,39

MARKET DYNAMICS OF SPECIFIC USE APPLICATIONS

The beneficial use markets for CCPs depend on the physical properties of the materials, the demand for 

their particular uses, and the supply of materials available for use. Exhibit 3-3, below, summarizes the 

current state of the beneficial use markets for the suite of CCPs, along with an analysis of the potential for 

growth in the beneficial use market for each material. An established market contains four key elements, 

all of which are interconnected:

 Generators producing a consistent supply of materials; 

 End-users with the demand to use the product;

 Well-known, accepted beneficial use applications; and 

 A distribution system to transport materials from generators to users. 

Limited markets may have a subset of these key elements, but likely need a shift in technology, demand, 

or price to increase beneficial use of the product. Emerging markets are typically unorganized and the 

connections between the elements are not fully formed. 

 

35 Energy & Environmental Research Center, University of North Dakota, “Review of Florida Regulations, Standards, and Practices Related to the 

Use of Coal Combustion Products: Final Report,” April 2006, accessed at http://www.undeerc.org/carrc/Assets/TB-FLStateReviewFinal.pdf. 

36 Some states, such as Wisconsin, have set up regulatory schemes designed to speed up the approval process for products using beneficial use 

materials such as CCPs. Currently, Wisconsin requires initial leachate testing of the material to be beneficially used, which leads to a specific 

rating. Materials that fall into a standard rating class are automatically approved for specific uses. For example, material found to meet drinking 

water standards can be used in any application, whereas material found to have a moderate level of contamination, may only be approved for 

encapsulated uses. Users are also required to submit annual reports demonstrating testing of CCPs. Personal communication with Bizhan 

Sheikholeslami, Wisconsin Department of Natural Resources, November 2006.

37 Further EPA study has revealed that in laboratory conditions, mercury is retained by fly ash and is “unlikely to be leached at levels of 

environmental concern.” Hassett, David J., Debra F. Pflughoeft-Hassett, Dennis L. Laudal, and John H. Pavlish. 1999. Mercury Release from Coal 

Combustion ByProducts to the Environment. However, this issue continues to be a focus of risk studies, and EPA’s Office of Research and 

Development is currently developing a life cycle inventory for cement production that reflects the impact of new mercury regulations. 

38 Personal Communication with Antoinette Stein, State of California Department of Health Services, June 2006.

39 Sanchez, F. et al, 2006. “Characterization of Mercury-Enriched Coal Combustion Residues from Electric Utilities Using Enhanced Sorbents for 

Mercury Control,” EPA-600/R-06/008, accessed Nov. 17, 2010 at http://www.epa.gov/ORD/NRMRL/pubs/600r06008/600r06008.pdf.
3-6

EXHIBIT 3-3: CCP BENEFICIAL USE MARKETS

CCP

STATE OF BENEFICIAL USE 

MARKET POTENTIAL FOR MARKET GROWTH

Fly Ash Established markets The markets for fly ash have the potential to continue to grow. 

Generators produce fly ash in large quantities and there are 

several well-known, high-value uses. Currently, only 42 perccent

of fly ash is beneficially used. 

FGD Gypsum Established markets The FGD gypsum market has room for moderate growth. FDG 

gypsum wallboard is an accepted alternative to virgin gypsum 

wallboard with users often directly connected to generators. 

Currently, 60 percent of FDG gypsum is beneficially used. Other 

uses are emerging but are currently limited, and data on market 

opportunities are limited.

Dry FGD Material Limited market The current market for dry FDG material appears to have only 

limited potential for growth. Uses for the material appear to be 

limited to relatively low-value uses, such mine reclamation. 

Currently, 25 percent of this material is beneficially used. Data 

on the market opportunities for this material are limited.

Wet FDG Material Limited market The current market for other FDG wet material appears to have 

only limited potential for growth. Uses for the material appear 

to be limited to relatively low-value uses, such mine reclamation. 

Currently, only five percent of this material is beneficially used. 

Data on the market opportunities for this material are limited.

Bottom Ash Established markets The markets for bottom ash have the potential to continue to 

grow. Generators produce bottom ash in large quantities and 

there are several well-known, high-value uses. Currently, 44 

percent of bottom ash is beneficially used. 

Boiler Slag Established markets The markets for boiler slag are mature and have limited 

opportunity for growth. Since approximately 83 percent of boiler 

slag is beneficially used (primarily as blasting grit), supply is 

currently roughly equivalent to demand.

FBC Ash Established markets The markets for FBC ash have potential for moderate growth, 

although mainly for low-value uses. Currently 93 percent of FBC 

ash is used. However, a majority is used in mining applications,

which EPA may consider disposal.

Cenospheres Emerging market The markets for cenospheres have the potential for growth as 

information on their uses becomes more widely available. 

However, information regarding potential uses and the current 

reuse rate is limited at this time. 

Aside from the boiler slag market and mining use of FBC ash, the markets for the various CCPs generally 

have at least modest capacity for growth. EPA efforts that aim to increase growth in the markets for 

CCPs by targeting beneficial use applications that are well-accepted practices in the industry may have 

significant success in helping expand these markets by overcoming targeted technical, administrative and 

technical and informational hurdles. The economic viability of two economically significant beneficial 
3-7

uses is considered individually below. Concrete and gypsum wallboard are long-standing, widely 

accepted uses for CCPs. 

Concrete

Certain performance benefits can be attained through the use of coal fly ash in concrete, including greater 

workability, higher strength, and increased longevity in the finished concrete product.40 Fly ash 

substitutes directly for portland cement in the concrete mixing process. This beneficial use represents one 

of the highest value applications for CCPs, and has the potential to increase as the demand for portland 

cement in the U.S begins to recover with the economy.

41

Industry representatives and some state agencies have stated that there are possible emerging issues 

related to regulatory programs for the control of nitrogen oxides (NOx) and mercury in power plant flue 

gases. These issues relate to the potential for negative impacts on coal fly ash quality and available

quantities due to the potential for increased mercury contamination in the ash, or unacceptably high levels 

of carbon content. There are technology choices that would minimize these impacts on the beneficial use 

of coal fly ash. However, the selection of equipment for control of nitrogen oxides and mercury, and 

corresponding technologies potentially necessary to minimize quality impacts on coal fly ash is very 

complex, resulting in industry solutions that would be unit-specific. Losses of anywhere between $40/ton 

and $80/ton of coal fly ash42 are possible if industry is unable to sell high carbon fly ash as a 

supplementary cementitious material in the manufacture of concrete. 

This estimate also includes the additional costs associated with the need to dispose of a formerly 

marketable material. State of Florida officials noted that installation of air emission controls at coal-fired 

power plants might result in increased mercury associated with coal fly ash. Since coal fly ash is used in 

portland cement manufacturing, electric utilities and portland cement manufacturers have expressed 

concern that the Florida Department of Environmental Protection’s (FDEP) New Source Review (NSR) 

might limit or even eliminate the use of CCPs for this purpose. Officials also noted that similar impacts 

might occur for coal fly ash containing higher levels of unburned carbon or other components resulting 

from changes in operations, fuel, or emission controls.43 This may have the potential of jeopardizing the 

recycling of many tons of CCPs that are currently reused.

The Texas CCP review also notes that emissions control in the electric utility industry has had a 

subsequent impact on the type, quantity, and quality of the solid materials produced at a specific power 

plant44. Officials indicate that the reduced supply of high quality coal fly ash already poses a threat to coal 

fly ash use in TX DOT projects, where high volumes of consistent quality coal fly ash are needed over the 

duration of large, long-term projects. 

Overall, technology options are available to the industry, specifically for the application of NOx controls, 

which would minimize any impacts on the quality of fly ash. Technology solutions are currently being 

 

40 Personal communication with Tom Pyle, Caltrans, November 2006.

41 The USGS January 2010 USGS Cement mineral commodity summary outlines a significant downturn in demand for cement as the recession and 

housing market contractions affected construction. 2009 saw closure of 14 plants (as three opened), and a decline of almost 30 percent in total 

production to 70 million tons from the market’s peak in 2005 of over 99 million tons. The commodity summary notes that while the industry is 

likely to recover, it will take several years to achieve 2005 production levels. 

42 Mercury-CCP dialogue meeting summary document, Final Draft, 1/14/08.

43 Energy and Environment Research Center (EERC), April 2006. Review of Florida Regulations, Standards, and Practices Related to the Use of Coal 

Combustion Products. 2006-EERC-04-03. University of North Dakota, Grand Forks, ND.

44 Energy and Environment Research Center (EERC), January 2005, “Review of Texas Regulations, Standards, and Practices Related to the Use of 

Coal Combustion Products,” 2005-EERC-01-01, University of North Dakota, Grand Forks, ND. 
3-8

developed and deployed in the industry to minimize or avoid any such impacts from the use of mercury 

controls as well. In addition, one study conducted by EPA Office of Research and Development found 

through laboratory tests that mercury is highly retained in fly ash and is “unlikely to be leached at levels 

of environmental concern.”45 However, research continues on the impact of changes in air pollution 

control technology on the ability to use fly ash in different applications.

Gypsum Wallboard

FGD gypsum is a product derived from the wet FGD process. Utilization of FGD gypsum in wallboard 

manufacture is a well-established market. Because the quality of FGD gypsum produced by power plants 

is generally consistent, new wallboard facilities often locate adjacent to power plants to allow FGD 

gypsum to be delivered directly to the wallboard plants. In some cases, wet FGD gypsum is piped directly 

to the adjacent wallboard facility, a step that significantly reduces transport and handling costs. Given 

these developments, the demand for FGD gypsum will likely remain high, and may increase as new 

wallboard manufacturing facilities are being constructed to accommodate FGD gypsum in wallboard 

production.46 

 

45 Sanchez, F. et al, 2006. “Characterization of Mercury-Enriched Coal Combustion Residues from Electric Utilities Using Enhanced Sorbents for 

Mercury Control,” EPA-600/R-06/008, accessed Nov. 17, 2010 at http://www.epa.gov/ORD/NRMRL/pubs/600r06008/600r06008.pdf.

46 Electric Power Research Institute, “Environmental Focus: Flue Gas Desulfurization By-Products,” 1999.
4-1

CHAPTER 4: IMPACTS ASSOCIATED WITH BENEFICIAL USE OF CCPs

To evaluate EPA's efforts to improve the beneficial use of CCPs, it is essential to quantify the important 

environmental and human health impacts of increased use of these materials in various beneficial use 

applications. An initial step in this process is describing the incremental environmental impacts associated 

with using a specific quantity (e.g., one ton) of CCPs in different applications. These impacts can then be 

extrapolated in specific scenarios designed to address program-level outcomes. This report draws on the 

data and methods used in life cycle assessment (LCA) to provide a screening-level description of the 

environmental impacts related to beneficial use of CCPs. 

This chapter first provides a brief overview of the use of LCA in the assessment of environmental impacts 

of beneficial use, and also discusses the relationship between LCA and the economic analysis of net 

social benefits. Next, the chapter identifies several available LCA tools that can be used to provide 

insights into the impacts of beneficial use of CCPs in different applications, and presents an initial life 

cycle inventory analysis of the potential impacts associated with the use of one ton of fly ash and FGD 

gypsum in concrete and wallboard manufacture, respectively. Finally, we note key limitations of this 

initial assessment and identify areas for additional research.

LIFE CYCLE INVENTORY ANALYSIS AND EPA PROGRAM OUTCOMES

Life cycle assessment (LCA) represents a proven methodology for describing the environmental impacts 

associated with changes in production systems. Specifically, LCA is a technique to assess the 

environmental aspects and potential impacts associated with a product, process, or service, by:

 compiling an inventory of relevant energy and material inputs and environmental releases;

 evaluating the potential environmental impacts associated with identified inputs and releases; and

 interpreting the results to help make a more informed decision.47

A complete LCA typically refers to a four-stage process that includes: 1) the definition of the goal and 

scope of the analysis, 2) an analysis of the life cycle inventory data (measurement of the changes in 

emissions, energy, and materials use and production related to the system); 3) assessment of specific 

environmental impacts (e.g., human health effects or “global warming potential”); and, 4) interpretation 

of results. 

In this report, EPA focuses specifically on a life cycle inventory analysis. The aim is to identify 

appropriate existing life cycle inventory data to characterize the changes in use of materials and energy, 

and the changes in emissions, that result from beneficial use of CCPs. Because the analysis relies on 

general production information and existing inventories, we do not attempt to assess environmental 

impact endpoints such as human health risk or global warming potential. 

A life cycle inventory depicts the production of materials as a system of complex physical outcomes, and 

can predict the incremental physical consequences of a change in material inputs, technology, waste 

management practices, or price incentives. In life cycle assessment, as in reality, one change in the 

physical system, such as the substitution of fly ash for virgin portland cement, leads to a corresponding 

cascade of economy-wide impacts and shifts. As inputs are substituted, technologies, physical outputs, 

 

47 EPA provides a general overview of LCA and introduction to a number of tools and resources on its web site: see 

http://www.epa.gov/nrmrl/lcaccess/ See also, International Standard on Environmental Management—Life Cycle Assessment—Goal and scope 

definition and inventory analysis (ISO 14041:1(E)). 
4-2

and exposure pathways change. Using a range of modeling platforms and life cycle inventories to 

calculate the outputs associated with each intermediate change, LCA calculates the net result of all of 

these interactions, capturing the total incremental effect of a change in operations on physical 

environmental impacts such as air emissions, and energy and water use. Life cycle assessment can be an 

effective performance assessment tool, and because it is a systems approach to assessment, it represents 

an improvement over less comprehensive techniques.

The SMM and other EPA programs are designed to help facilitate changes in the economics and practice 

of waste generation, handling, and disposal (e.g., by promoting market opportunities for beneficial use). 

The outcomes of the program, therefore, can be described as the changes in total environmental impacts 

that result from changes in beneficial use. Many of these impacts likely come from avoiding the 

production of virgin materials that would be used in the absence of industrial materials. In some cases, 

changes in materials use may also lead to (positive and negative) changes in processing, product 

performance, and disposal approaches. LCA can, given appropriate data and modeling scenarios, 

describe the net impacts of all of these changes, and can, therefore, provide an assessment of program 

results.

Life Cycle Assessment and Economic Benefit Assessment

As a tool for measuring physical impacts of system changes, LCA is a natural starting point in the 

assessment of the economic benefits of a program, but it is important to distinguish between LCA and 

economic benefits analysis. LCA is useful in the context of benefits analysis because it reflects a systems 

approach, allows measurement of changes to baseline conditions, identifies tradeoffs, and yields concrete, 

measurable metrics that can be evaluated both in isolation and comparatively, across programs and 

activities. 

However, while it can provide a clear assessment of beneficial (and other) program impacts, LCA does 

not itself measure the social benefits and costs of changes in practice, for two reasons. First, LCA 

provides a static examination of impacts based on a one-time change to a system, and does not attempt to 

measure net impacts over time, adjusting for long-term market responses (e.g., changes in price and 

behavior) that can, in turn, affect the long-term system operation.48 Beneficial use of large-volume CCP 

materials, such as fly ash and FGD gypsum, is already well-established. Therefore, gradual increases in 

use of these materials may have some impact on the large cement and gypsum markets in the U.S., but 

this analysis assumes that dramatic near-term changes in the market are unlikely. Therefore, the impacts 

estimated by LCA are reasonable representations of total market impacts. However, if sudden, largescale changes in production of raw materials occur as a result of SMM efforts, then a net economic 

impact analysis using methods like partial equilibrium analysis might be necessary. 

Second, a complete assessment of the net economic benefits of a program requires the application of 

economic valuation techniques to the physical outputs of LCAs, in order to describe, in economic terms, 

what the physical outcomes imply for human well-being. For example, an LCA can describe changes in 

the quantity of water used or waste generated in a process, but is not designed to identify the specific 

effect of these impacts on well-being.49 While LCA impact assessment techniques can in some cases 

 

48 For example, a beneficial use that has a significant impact on raw material demand (e.g., for virgin aggregate) and on electricity demand may 

ultimately affect the local prices of both energy and raw materials as demand for these commodities drops. The price changes could, in turn, 

result in other changes in practice (e.g., decisions on the part of other purchasers to buy more aggregate or changes in use patterns of 

electricity). These impacts would likely have some impact on the net change in environmental impacts measured in the LCA. 

49 LCA can incorporate impact assessments using a range of different methods that can, at a minimum, provide comparative descriptions of the 

types of damage likely associated (or avoided by) the system change. However, valuation of specific impacts (e.g., health impacts from air 
4-3

provide general insights into typical impacts such as eutrophication or health risk, economic valuation of 

these changes often depends upon the specific location, timing, and quality of the water that is consumed 

or waste disposal that occurs. The value of that water depends on how it would otherwise be used (e.g., 

for human consumption, industrial uses, habitat support, irrigation) and the “value” of the waste depends 

on the health risks it poses, release scenarios, and the people exposed.50 

Ideally, LCA would be incorporated into a full-scale analysis of net program benefits that would account 

for market responses and would value specific environmental impacts such as decreased releases of 

pollutants. Unfortunately, the translation of physical changes into economic outcomes is typically costly, 

difficult, and often controversial when applied to human health or environmental outcomes. It frequently 

requires location-specific data on releases and exposures, as well as well-documented links between these 

exposures and health or environmental impacts. Assigning an economic value to even a small set of 

physical impacts can be a significant and expensive undertaking.51

Accordingly, LCA can represent not only a necessary ingredient, but also a practical initial alternative to a 

complete economic benefit assessment. While net economic benefits are often the target performance 

measure, it is necessary in many cases to rely on simpler proxies to facilitate management and 

performance assessment. As proxies, LCA outputs can represent a legitimate and defensible measure of 

program impacts. Therefore, we use LCA to investigate the measurable beneficial impacts associated with 

SMM program achievements, using available LCA tools. A more detailed discussion of the role of LCA 

in economic benefits assessment is provided in Appendix C. 

ASSESSMENT OF BENEFICIAL IMPACTS OF CCP USE

To fully capture the beneficial impacts of EPA’s efforts to increase beneficial use of CCPs, it would be 

necessary to model each beneficial use application of all CCPs targeted by the SSM. However, the time, 

data, and resources required to perform this task are beyond the scope of this report. For this preliminary 

analysis, we have selected two common CCPs, fly ash and FGD gypsum, which have well-understood 

beneficial use applications and processes, and for which life cycle models and existing data are available.

We conducted a comprehensive review of available data sources and tools for assessing life cycle benefits 

of beneficial use of these materials across all possible use applications. We identified four models that 

support specific evaluation of the environmental impacts of avoided virgin materials extraction in 

processes where CCPs are beneficially used in place of virgin materials:

 Building for Environmental and Economic Sustainability (BEES) was developed by the 

National Institute of Standards and Technology (NIST) with support from the U.S. EPA to allow 

designers, builders, and product manufacturers to compare the life cycle environmental, and 

economic performance of alternative building products.52 The BEES methodology measures 

 

releases) requires modeling of specific exposure scenarios; LCA is designed specifically to address systems without requiring unique locationspecific information.

50 Hendrickson, Lave, and Matthews (2006) notes the limitation of LCA outputs that are not linked to specific locations and exposures - “A typical 

[Life Cycle Inventory] of air pollution results in estimates of conventional, hazardous, toxic, and greenhouse gas emissions to the air. Even 

focused on this small subset of environmental effects, it is unclear how to make sense of the multiple outputs and further how to make a 

judgment as to tradeoffs or substitutions of pollutants among alternative designs.”

51 In the ecological realm, these kinds of translations are underdeveloped. The agency is aware of this ongoing limitation. For example, this 

conclusion has been drawn from several recent SAB reports, including EPA-SAB. 2003. "Underground Storage Tanks (UST) Cleanup & Resource 

Conservation & Recovery Act (RCRA) Subtitle C Program Benefits, Costs, & Impacts (BCI) Assessments: An SAB Advisory." (EPA-SAB-EC-ADV-03-001) 

and "Advisory on EPA's Superfund Benefits Analysis." (EPA-SAB-ADV-06-002). In addition, the SAB Committee on Valuing the Protection of 

Ecological Systems and Services is currently examining methods for addressing these limitations.

52 The BEES model and supporting documentation are accessible at http://www.bfrl.nist.gov/oae/software/bees.html.
4-4

environmental performance using an LCA approach, following guidance in the International 

Standards Organization 14040 series of standards for LCA. Thus, all stages in the life of the 

product are analyzed: raw material acquisition, manufacture, transportation, installation, use, and 

recycling and waste management. The BEES model is implemented in publicly available 

decision-support software, complete with actual environmental and economic performance data 

for a number of building products. 

 SimaPro was developed by the Dutch company Pré Consultants and can be used to perform 

detailed lifecycle analyses of complex products and processes. SimaPro provides a high degree of 

modeling flexibility in that it provides data profiles representing thousands of materials 

production, transport, energy production, product use and waste management processes that can 

be combined to model very specific systems. Thus, SimaPro relies on the user’s understanding of 

the various lifecycle stages and processes in the system being modeled. Results can be displayed 

as lifecycle inventory flows (e.g. energy use, water use and pollutant emissions (for a variety of 

pollutants including the criteria pollutants). In addition, one of several impact assessment 

methods can be applied to characterize the environmental damages (e.g., global warming, 

eutrophication, etc.) associated with these flows.

 Pavement Life Cycle Assessment Tool for Environmental and Economic Effects (PaLATE)

is an Excel-based tool developed by the Consortium for Green Design and Manufacturing at U.C. 

Berkeley for life cycle inventory analysis of environmental and economic performance of 

pavements and roads. The model was developed for pavement designers and engineers, 

transportation agency decision-makers, civil engineers, and researchers. PaLATE can evaluate the 

relative impacts of using different virgin and secondary materials in the construction and 

maintenance of roads. Based on user-specified data on the type and quantity of initial construction 

materials, road construction equipment (e.g., asphalt paver), material transportation distances and 

modes, maintenance materials and processes, and off-site processing equipment (e.g., rock 

crusher), PaLATE calculates twelve life cycle inventory flows including water and energy use, 

conventional air emissions (NOx, SO2, CO2, PM10, and CO), toxic air emissions (Pb and Hg), 

RCRA hazardous waste generation; and cancer and non-cancer Human Toxicity Potentials.53

 The WAste Reduction Model (WARM) was created by EPA to help solid waste planners and 

organizations estimate greenhouse gas (GHG) emission reductions from several different waste 

management practices. WARM calculates GHG emissions for baseline and alternative waste 

management practices, including source reduction, recycling, combustion, composting, and 

landfilling. The user can construct various scenarios by entering data on the amount of waste 

handled by material type and by management practice. WARM then automatically applies 

material-specific emission factors for each management practice to calculate the GHG emissions 

and energy savings of each scenario. In addition, the model will convert these outputs to 

equivalent metrics including the equivalent number of cars removed from the road in one year, 

the equivalent number of avoided barrels of oil burned, and the equivalent number of avoided 

gallons of gasoline consumed. 

 

53 PaLATE does not allow for life cycle assessment of the inventory results, but in other life cycle models, impact assessment methods can be 

applied to inventory results to estimate environmental damages.
4-5

All four models support life cycle assessment of various CCPs. PaLATE, BEES and WARM all include 

life cycle inventory data to evaluate use of fly ash as a substitute for finished portland cement in concrete, 

and SimaPro supports evaluation of use of FGD gypsum in wallboard. We select BEES and SimaPro to 

evaluate fly ash and FGD gypsum beneficial use because these models have been peer-reviewed and 

evaluate a large suite of environmental metrics.54 In contrast, PaLATE has not undergone a formal peer 

review process, and WARM evaluates only energy use and greenhouse gas metrics. For comparative 

purposes, however, we present the results of a WARM analysis of the use of fly ash in concrete in 

Appendix D.

55

In addition to BEES and SimaPro, the U.S. Economic Input-Output Life Cycle Assessment (EIO-LCA) 

model provides an alternative approach for measuring the avoided upstream impacts of recycling. EIOLCA was developed at Carnegie Mellon University and provides the capacity to evaluate economic and 

environmental effects across the supply chain for any of 491 industry sectors in the U.S. economy. EIOLCA also can represent the supply chain use of inputs and resulting environmental outputs across the 

supply chain by using publicly available data sources from the U.S. government. By integrating 

economic data on the existing flow of commerce between commodity sectors with environmental data on 

releases and material flows generated by each sector, it is possible to estimate the additional 

environmental emissions caused by an increase in production within a particular sector, accounting for 

changes in the supply chain. This approach can be used to provide insight into the sectors of the economy 

that drive the environmental impacts of a given process, and shed light on the specific impacts of 

particular policy efforts. While it is very helpful in examining the distribution of impacts across 

economic sectors, the EIO-LCA is not optimal for a specific life cycle assessment of beneficial use of 

FGD gypsum in wallboard because the life cycle impacts are modeled at the sector level and do not 

provide the same process-level resolution that can be estimated for various use applications using 

SimaPro. EIO-LCA is more useful for modeling use of fly ash in concrete, as it includes data for a fairly 

homogenous cement sector. It is also important to note that EIO-LCA is a dollar-based model and thus, is 

not directly comparable to the BEES/SimaPro data that is presented in tons. Appendix D describes supply 

chain manufacturing impacts for cement and gypsum production modeled using EIO-LCA.

METHODOLOGY FOR EVALUATING UNIT IMPACTS OF BENEFICIAL USE

We conduct separate analyses to evaluate the incremental environmental impacts associated with 

beneficially using a specific quantity (i.e., one ton) of fly ash and FGD gypsum. We employ:

 BEES to investigate using one ton of fly ash as a substitute for finished portland cement in 

concrete; and

 SimaPro to investigate using one ton of FGD gypsum as substitute for virgin gypsum in 

wallboard.

While it is not optimal to use two different models in a single analysis, in this case we employed the 

BEES tool to be consistent with previous analyses of beneficial use of materials in other reports; BEES 

does not address gypsum. This analysis is designed to examine the general magnitude of potential 

 

54 BEES has reliable data for the use of fly ash in concrete, but it does not evaluate use of FGD gypsum in wallboard. SimaPro does allow evaluation 

of both fly ash and FGD gypsum but we prefer the U.S.-based data in BEES to conduct the fly ash analysis. For this reason, we do not use the same 

model for both analyses.

55 The PaLATE model was used to evaluate beneficial use of fly ash in previous iterations of this report, but we omit the PaLATE analysis from this 

version in order to avoid comparisons of peer reviewed model findings to non-peer reviewed model findings for CCPs. It is important to note, 

however, that PaLATE relies on much of the same LCI data as the EIO-LCA model, which is presented in Appendix C.
4-6

environmental impacts, and the use of SimaPro for specific materials not addressed in BEES provides 

additional insights into the potential impacts of beneficial use of CCPs. 

The first step in evaluating the life cycle impacts of beneficial use of fly ash and FGD gypsum is 

development of environmental impact profiles for use of one ton of each material as a substitute for 

portland cement in concrete and for virgin gypsum in wallboard, respectively. One ton was selected as the 

unit-basis for these analyses because the impacts can then easily be extrapolated to current use quantities, 

which are reported by ACAA in tons. In addition, by developing life cycle benefits profiles for use of a 

consistent quantity of each material, the impact profiles of specific materials can be compared with each 

other. 

The calculation of unit impact values for fly ash and FGD gypsum are described in greater detail below. 

To the extent possible, we attempt to use comparable assumptions and life cycle system boundaries in 

both analyses. We express beneficial use quantities in short tons (consistent with EPA and ACAA), but 

report impacts in metric units, consistent with BEES and SimaPro results.

BEES Analysis of Use of Fly Ash in Concrete

BEES includes environmental performance data for a number of concrete products (e.g., concrete 

columns, beams, walls, and slab on grade). The user can compare the environmental performance data of 

each of these products using different pre-determined concrete mix-designs, some of which include fly 

ash. The BEES environmental performance data serve as quantified estimates of the energy and resource 

flows going into the product and the releases to the environment coming from the product, summed 

across all stages of the product life cycle for one cubic yard of concrete. BEES quantifies these flows for 

hundreds of environmental metrics, but to capture the general spectrum of impacts, we focus on the 

following:

 Total primary energy use (MJ);

 Renewable energy use (MJ);

 Nonrenewable energy use (MJ);

 Water use (liters);

 Atmospheric emissions (CO2, methane, CO, NOx, SOx, particulates, Hg, Pb) (grams);

 Waterborne waste (suspended matter, biological oxygen demand, chemical oxygen demand, Hg, 

Pb, selenium; and

 Nonhazardous waste (kg).

As an example of the LCA approach, we assess the beneficial environmental impacts of using fly ash to 

offset virgin cement inputs in a concrete beam with a compressive strength of 4 KSI (4,000 psi) and a 

lifespan of 75 years. It is important to note that this concrete product was selected to represent use of fly 

ash in any generic concrete application; the unit impact values do not reflect any assumptions specific to 

the life cycle of a concrete beam in BEES.56 Furthermore, any concrete building product data set could 

 

56 All concrete building product data in BEES (e.g., concrete columns, beams, walls, and slab on grade) use a 75-year lifespan assumption. 

Calculating unit impact values using data from any one of these products yields the same values. In addition to life cycle inventory data for 

concrete building products, BEES also includes data for a concrete parking lot pavement. The concrete parking lot data, however, use a 30-year 

lifespan assumption; calculating unit impact values using pavement data yields values that are approximately 2.5 times greater than the values 

calculated from building product data because the pavement data assume a 2.5 times shorter lifespan than building products. 
4-7

have been used without changing the unit impact value. For further details on the life cycle inventory data 

used in this analysis, refer to Appendix E.

The benefits of fly ash use are measured as the difference in environmental impacts between a baseline 

scenario and a beneficial use scenario. In the baseline scenario, a one cubic yard 4 KSI concrete beam is 

produced using 100 percent portland cement. In the beneficial use scenario, a one cubic yard 4 KSI 

concrete beam is produced using 15 percent coal fly ash and 85 percent portland cement.57, 58 The 

difference in environmental impacts between the baseline and beneficial use scenarios represents the 

change in impacts from substituting 15 percent of the portland cement with fly ash in one cubic yard of 4 

KSI concrete. We translate these impacts from a cubic yard concrete basis to a ton fly ash basis by 

dividing the impacts by the absolute quantity of fly ash in one cubic yard of the concrete product. For an 

illustration of this methodology, refer to Appendix E. 

SimaPro Analysis of FGD Gypsum in Wallboard

We calculate the unit impacts of using FGD gypsum in place of virgin gypsum stucco in wallboard as the 

difference in impacts between wallboard made with 100 percent virgin gypsum and wallboard made with 

100 percent FGD gypsum. We model these impacts as one ton of avoided “stucco” manufacture in 

SimaPro.59 Stucco is the term used in SimaPro to describe the gypsum material used in wallboard. We 

selected the EcoInvent v2.2 data set because it includes gypsum mining but also includes the processing 

of gypsum for use in wallboard (i.e., burning of gypsum and milling of stucco for use in gypsum 

wallboard). Thus, this dataset includes all the processes that would be avoided if an equivalent quantity of 

FGD gypsum were used in place of stucco in wallboard. The production of FGD gypsum from coal 

combustion is not modeled, as discussed in the following section on allocation of life cycle impacts to 

FGD gypsum. In addition, this analysis assumes that FGD gypsum dewatering occurs via holding ponds 

and that the environmental impacts of dewatering are negligible.60 This analysis also does not model 

transport distance; we assume FGD gypsum would have the same transport distances to the construction 

site as virgin gypsum.61 Thus, avoided gypsum mining and avoided processing of gypsum into stucco, as 

represented by the EcoInvent stucco manufacturing data set, are the only lifecycle stages modeled in 

SimaPro. Appendix E provides more information on the FGD gypsum analysis.

Allocation of Life Cycle Impacts to CCPs

As EPA programs evolve to emphasize both beneficial use of industrial materials and life cycle 

assessment approaches to evaluating these programs, it is important to consider upstream impacts of the 

processes that create beneficial use materials, including, in this case, the impacts of the electrical power 

generation industry that produces CCPs for beneficial use.

 

57 Fly ash replaces portland cement in concrete in a one to one ratio based on mass.

58 Both the concrete beam made with and without blended cement assume a 60-mile round trip transport distance for portland cement and fly ash 

and a 50-mile round-trip transport distance for aggregate to the ready-mix concrete plant. 

59 We use the EcoInvent data set titled “Stucco, at plant/CH U” for this purpose.

60 There may actually be emissions/dusting impacts associated with dewatering in a holding pond, but we have been unable to identify quantified 

estimates of these impacts. Alternatively, dewatering may be accomplished through mechanical processes but we were also unable to identify the 

energy impacts of mechanical dewatering. 

61 We do not model a transport differential between virgin and FGD gypsum to be consistent with the transport assumptions used in the BEES fly ash

analysis, which helps preserve the comparability of the fly ash and FGD gypsum unit impact values. It is important to note, however, that an 

increasing number of new gypsum wallboard plants are being constructed adjacent to coal-fired power plants, so the transport distance of FGD 

gypsum to the wallboard manufacturing facility may, in some cases, be less than the transport distance of virgin gypsum.
4-8

The beneficial use of CCPs has positive environmental and energy impacts relative to landfilling and 

virgin material production. Consideration of the negative upstream impacts of electricity production 

through "allocation" does not actually reduce the beneficial impacts of beneficial use, nor does it "create" 

negative impacts. Instead, it represents a quantitative way of identifying the extent to which CCPs are 

associated with the generation of coal-fired power and are not an environmentally “free” product.

Analysis of life cycle impacts is, in its simplest form, the calculation of all impacts associated with a 

single production system (e.g., the manufacture of paper, or the production of energy using coal). 

However, when one production system (or a set of linked production systems) makes two or more 

products with market value (i.e., co-products), it is accepted practice in LCA to recognize that these 

products are associated with environmental impacts, and to allocate the total life cycle production impacts 

across these products.62 Several methods for allocation are possible, depending on the system(s), inputs, 

and the quantity and value of co-products. Simple methods include allocating impacts proportionately by 

total mass or by market value; more complex methods may be necessary when integrated systems use 

different types of inputs or produce a range of products with different features and environmental profiles.

Waste is not considered a co-product, and it is, therefore, generally unnecessary to allocate specific 

production impacts to materials that are destined for disposal (disposal impacts are allocated 100 percent

to the producing industry). However, when an industrial material becomes a beneficial use material and 

ceases to be considered a waste, it reflects a market value. It is, therefore, a co-product, though typically 

a very low-value one when compared to the primary products of the industry (in this case, electricity). It 

is important to consider whether co-products of electricity generation (such as fly ash and FGD gypsum) 

that are beneficially used should have some portion of the production impacts associated with coal 

combustion (e.g., energy use, greenhouse gas equivalents, releases to air and water) attributed to them.63

In Appendix E, we provide an illustration of a potential approach for allocating the environmental and 

energy impacts from coal-fired power generation across electricity generation and CCPs. The analysis 

considers some hypothetical macro-level scenarios for coal-fired power generation, as well as macro-level 

flows of several key CCPs. The preliminary analysis in Appendix E is designed to assess the implications

of allocating the environmental effects of power generation to both the energy product and the CCPs. 

Using both an economic and a mass-based approach, we find that the only small flows would be allocated 

to the CCPs relative to the impacts of electricity production (i.e. less than one percent in the case of massbased allocation). 

At this time the majority of CCPs are still disposed. In addition, the small environmental impacts 

allocation indicated by our preliminary analysis in Appendix E, and the high uncertainty associated with 

fuel sources, prices of electricity generation, and CCP prices limit the use of any illustration of allocation 

options. Therefore, we do not currently include either an economic or mass-based allocation of coal 

combustion impacts to fly ash or FGD gypsum into this analysis. However, to fully understand the 

potential impacts of beneficial use on coal combustion, and to fully characterize the benefits associated 

with beneficial use, it may be important to assess these potential impacts under various analytical 

scenarios as EPA's policies and programs evolve. 

 

62 A discussion of general principals for allocation is presented in the International Standard on Environmental Management—Life Cycle Assessment—

Goal and scope definition and inventory analysis (ISO 14041:1(E)), pp.11-12, and Annex B. 

63 It is important to stress that allocated impacts are not actual impacts associated with the beneficial use of the materials; in most cases use is 

significantly more beneficial than disposal. Instead, allocation is a means of placing the beneficial use materials in the context of their original 

production and recognizing that the processes that produce these byproducts may incur environmental costs.
4-9

One reason to consider allocation, even hypothetically, is to consider the potential impact of policies on 

both economic and environmental outcomes. Typically, as with fly ash and FGD gypsum, the economic 

value of beneficial use materials is small in comparison to the value of primary products of the producing 

industries. However, it is conceivable that significant increases in the value of beneficial use materials 

could alter the economics of the producing industries. While it is unlikely that any industry would alter 

production to increase production of beneficial use materials, demand for these materials could improve 

the cost structure of certain industrial processes. For example, increased demand for CCPs could improve 

the cost structure for coal-fired power plants and improve their competitive position in energy markets.64

As beneficial use and the economic value of various industrial materials increases, it becomes 

increasingly important to accurately account for the processes that produce the materials as well as the 

processes that use them.

RESULTS

For both the baseline and beneficial use scenarios, BEES and SimaPro generate quantitative estimates of 

impacts for a suite of environmental metrics. For each metric, environmental outputs under the baseline 

and beneficial use scenarios represent life cycle impacts of replacing virgin materials with CCPs. Where 

this difference is positive, the impact is an environmental benefit of using CCPs in place of virgin 

materials. Where the difference is negative, use of CCPs suggests a decline in environmental quality. 

Exhibit 4-1 presents the results of the analyses of use of fly ash in concrete and use of FGD gypsum in 

wallboard.

 

64 An example of a system in which dramatic changes in co-product value have driven production changes is the recent change in demand for 

ethanol, which has resulted in a significant increase in demand for agricultural by-products and has altered production decisions to meet this new 

demand.
4-10

EXHIBIT 4-1: LIFECYCLE ASSESSMENT OF POTENTIAL IMPACTS OF CCP BENEFICIAL USE 

AVOIDED IMPACTS

PER 1 TON FLY ASH AS PORTLAND 

CEMENT IN CONCRETE

PER 1 TON FGD GYPSUM IN 

WALLBOARD

ENERGY USE

NONRENEWABLE ENERGY (MJ)a

5,361.70 1,319.69

RENEWABLE ENERGY (MJ)b

0 14.56

TOTAL PRIMARY ENERGY (MJ)c

5,361.70 1,334.25

TOTAL PRIMARY ENERGY (US$)d

23.59 21.67

WATER USE

TOTAL WATER USE (L) 689.36 88,973.02

TOTAL WATER USE (US$)

e

0.44 67.39

GREENHOUSE GAS EMISSIONS

CO2 (G) 995,744.68 78,830.56

METHANE (G) 842.55 171.71

AIR EMISSIONS

CO (G) 1,378.72 38.04

NOX (G) 2,680.85 152.43

SOX (G) 2,451.06 192.01

PARTICULATES GREATER THAN PM10 (G) 0.00 1,209.24

PARTICULATES LESS THAN OR EQUAL TO PM10 (G) 7.66 472.58

PARTICULATES UNSPECIFIED (G) 2,374.47 0.00

MERCURY (G) 0.08 0.00

LEAD (G) 0 0.03

WATERBORNE WASTES

SUSPENDED MATTER (G) 490.21 12.63

BIOLOGICAL OXYGEN DEMAND (G) 22.98 23.11

CHEMICAL OXYGEN DEMAND (G) 45.96 24.14

COPPER (G) 0.00 0.00

MERCURY (G) 0.00 0.00

LEAD (G) 0.00 0.01

SELENIUM (G) 0.00 0.01

NONHAZARDOUS WASTE (KG)f

0.00 0.00
4-11

AVOIDED IMPACTS

PER 1 TON FLY ASH AS PORTLAND 

CEMENT IN CONCRETE

PER 1 TON FGD GYPSUM IN 

WALLBOARD

Notes:

a. Nonrenewable energy refers to energy derived from fossil fuels such as coal, natural gas and oil.

b. Renewable energy refers to energy derived from renewable sources, but BEES does not specify what sources these include.

c. Total primary energy refers to the sum of nonrenewable and renewable energy.

d. We monetize energy impacts for fly ash using a price figure ($0.0044/MJ) derived from the average price of purchased energy 

to the cement manufacturing sector in 2006 ($4.36/million BTU), from Table 7.2, accessed on Nov. 16, 2010 at 

http://www.eia.doe.gov/emeu/mecs/mecs2006/2006tables.html. The cost was converted to 2009 dollars using NASA's Gross 

Domestic Product Deflator Inflation Calculator, accessed on April 22, 2010 at http://cost.jsc.nasa.gov/inflateGDP.html. We 

monetize energy impacts for FGD Gypsum using a price/MJ figure ($0.0179/MJ), derived from the average cost of diesel fuel in 

2009 ($2.467/gallon), assuming 130,500 BTUs/gallon of diesel fuel. Diesel price is 2009 weekly price of on-highway diesel 

accessed on April 22, 2010 at http://tonto.eia.doe.gov/dnav/pet/pet_pri_gnd_dcus_nus_a.htm; diesel energy value accessed 

April 22, 2010 at http://bioenergy.ornl.gov/papers/misc/energy_conv.html.

e. We monetize water impacts using the average cost of water in 2008 ($2.81/KGal) converted to 2009 dollars ($2.87/KGal). The 

2008 cost of water is taken from NUS Consulting Group, accessed on April 22, 2010 at http://www.marketwire.com/pressrelease/Average-US-Water-Costs-Increase-by-73-903477.htm. The cost was converted to 2009 dollars using NASA's Gross 

Domestic Product Deflator Inflation Calculator, accessed on April 22, 2010 at http://cost.jsc.nasa.gov/inflateGDP.html.

f. BEES reports waste as “end of life waste.” In contrast, SimaPro reports “solid waste.” In is not clear if these waste metrics are 

directly comparable as SimaPro does not specify whether “solid waste” refers to manufacturing waste, end-of-life waste, or 

both.

As shown in Exhibit 4-1, the results of the fly ash and FGD gypsum analyses suggest many positive 

environmental impacts associated with beneficial use. For most metrics, there is a significant difference 

between the unit impact value for fly ash and FGD gypsum. The difference in unit impact values reflects

different avoided processes when fly ash is used to offset portland cement versus when FGD gypsum is 

used to offset virgin gypsum. For example, the primary driver of benefits when fly ash is used in concrete 

is avoided raw materials extraction and avoided portland cement production.65 In comparison, the primary 

driver of benefits when FGD gypsum is used in wallboard is avoided virgin gypsum extraction and the 

processing of virgin gypsum into stucco. Portland cement production generates relatively high greenhouse 

gas emissions. Thus, the avoided CO2 and methane emissions are greater for fly ash than for FGD 

gypsum in this analysis. In contrast, gypsum mining requires comparatively higher quantities of water, so 

the water savings are greater for FGD gypsum in this analysis than for portland cement. 

In addition, the difference in unit impacts may reflect differences in the assumed system boundaries 

between the two analyses. It is unclear how the BEES system boundaries compare to SimaPro. Thus, the 

total life cycle impacts calculated in BEES could be large or small in comparison to the system 

boundaries in the SimaPro FGD gypsum analysis.

LIMITATIONS AND ASSUMPTIONS

Although the BEES analysis provides a useful example of the benefits that can be achieved through 

beneficial use of fly ash in concrete, it is important to recognize some of the key limitations and 

assumptions of the work to date:

 The BEES model may over or underestimate the national impacts of using fly ash in concrete

construction projects because site-specific environmental conditions and proximity to sources of 

fly ash may affect the resulting benefits and influence the net effect of choosing fly ash over 

portland cement.

 

65 It is unclear from the documentation provided for BEES what impacts (e.g. virgin materials extraction, plant infrastructure, etc.) are modeled for 

portland cement production. For this reason, it is not possible to explain the differences in unit impact results between the FGD gypsum and fly 

ash analysis.
4-12

 BEES assumes round-trip distances for the transport of concrete raw materials to the ready-mix 

plant of 50 miles for portland cement and fly ash and 50 miles for aggregate. This analysis also 

assumes the minimum possible transport distances for the finished concrete products to the 

construction site. This transport distance for ready-mix concrete for a pavement application is 50 

miles.

 BEES environmental results are reported in physical quantities (e.g., MJ energy, liters water, g 

CO, g NO, g Hg, etc.), not in monetized terms. 

 In BEES, the calculation of each environmental impact is not fully transparent. BEES does 

disaggregate the total life cycle impact value for each environmental metric (e.g., energy use, CO2

emissions, etc.) by lifecycle stage and by product component, but it is not possible to see exactly 

how each impact is derived. This limits the user’s ability to compare the results of the BEES 

model with those of others models, such as SimaPro.

 The FGD gypsum analysis is based on a Swiss life cycle inventory data. While we substituted 

Swiss electricity data with the average U.S. energy mix, it is unclear whether the average U.S. 

energy mix is an accurate representation of the electricity mix used in wallboard manufacturing. 

Given the recent trend in new wallboard facilities being constructed adjacent to coal-fired 

powered plants, it is possible that these facilities use primarily coal-based electricity. With the 

exception of energy mix, it is unlikely that any other differences between European and U.S. 

gypsum extraction and stucco processing would result in meaningful differences in environmental 

impacts. 

 The FGD gypsum analysis assumes that dewatering of FGD gypsum is accomplished through 

evaporation in holding ponds. To the extent that the predominant practice is to use mechanical 

dewatering processes, the analysis should be modified to reflect this. The assumption of 

dewatering via holding ponds likely overstates the energy and energy-related emissions impacts 

in this analysis, since the impacts of dewatering, which are subtracted from the avoided gypsum 

processing impacts, would be greater for mechanical dewatering than for holding pond 

evaporation.
5-1

CHAPTER 5: ESTIMATING PROGRAM LEVEL IMPACTS

This chapter provides an overview of an initial, life-cycle based approach to evaluating program level 

impacts associated with the SMM effort to increase beneficial use of CCPs. The chapter first outlines two 

critical steps necessary for a complete evaluation of specific program impacts:

 Development of defensible beneficial use scenarios that reflect likely market trends, policy 

efforts, and key limitations; and 

 Implementation of a well-supported attribution protocol for assigning beneficial use impacts to 

specific EPA programs. 

This discussion is followed by a preliminary analysis of the total impacts associated with current 

(baseline) beneficial use patterns, based on an extrapolation of the life cycle inventory impacts identified 

in Chapter 4. The purpose of this chapter is to present an initial estimate of the measurable impacts 

associated with current levels of beneficial use of CCPs, and to outline the steps necessary to provide a 

refined, program-specific analysis of EPA's efforts through the SMM to increase beneficial use of CCPs.

DEVELOPMENT OF DEFENSIBLE BENEFICIAL USE SCENARIOS

Life cycle inventories (LCI) and LCA provide comprehensive information on the impacts associated with 

given quantities of materials used in specified systems. The impacts measured by LCA models are 

typically linear; as the quantity of CCPs used in a particular application (e.g., concrete) is increased, the 

environmental impacts increase proportionately.

While LCA can provide insights into the potential magnitude of program benefits, in some cases existing 

market limitations and trends suggest that a linear extrapolation of current practices would be unrealistic. 

An effective assessment of true program impacts requires the development of defensible market scenarios 

that accurately identify the extent to which different beneficial uses are likely to increase, given the 

realities of the existing and emerging markets for beneficial use and the structure of SMM programs. 

Current Market Dynamics: Factors Affecting Beneficial Use

Several market factors can limit the increased beneficial use of CCPs in various products. In some cases 

programs can be designed to address these factors effectively. Exhibit 5-1 outlines several of these 

factors and presents hypothetical actions that might address them. It is important to note that the actions 

described below are intended only to illustrate possible conditions for increasing the beneficial use of 

CCPs; they do not represent specific policy recommendations or existing program priorities.

EXHIBIT 5-1: LIMITING FACTORS TO INCREASED BENEFICIAL USE OF CCPs

FACTOR TYPE

FACTORS AFFECTING 

INCREASED BENEFICIAL USE

HYPOTHETICAL ACTIONS

TO INCREASE BENEFICIAL USE

Economic

Transportation costs generally limit the shipment of 

CCPs to within about a 50 to 150 mile radius of power 

plants. In some cases, however, the cost of transport 

to the end user may be prohibitively expensive.

Implementation of strategic actions to create 

incentives to increase beneficial use by shifting 

the economic drivers (i.e., cost of materials) in 

favor of CCPs. Potential incentives could include 

tax credits for the use of CCPs, increased CCP 

landfill disposal tipping fees, or streamlining the 

permitting process for facilities that use CCPs near 

coal combustion plants (e.g., FGD gypsum plants). 

In some parts of the country and for certain use 

applications, the cost of virgin materials may be 

cheaper than CCPs.
5-2

FACTOR TYPE

FACTORS AFFECTING 

INCREASED BENEFICIAL USE

HYPOTHETICAL ACTIONS

TO INCREASE BENEFICIAL USE

Inexpensive landfill disposal can limit incentive to sell 

rather than dispose of CCPs.

Institutional

National standards organizations have promulgated 

specifications that limit or disallow the use of CCPs in 

some construction applications because of quality and 

performance concerns and perceptions.

State DOTs rely on consensus standards for 

guidance and generally accept the use of fly ash in 

concrete. DOT projects can be used to 

demonstrate the performance of CCPs in 

geotechnical applications.

The implementation of the U.S. Clean Air Mercury Rule 

(CAMR) may result in altering the chemical properties 

of fly ash, rendering it unmarketable for beneficial 

use. 

Similar impacts may also occur for fly ash containing 

higher levels of unburned carbon or other components

resulting from installation of low-NOx burners at coalbased power plants. 

Establishment of a research and development 

infrastructure to address the technical limiting 

factors to CCP use.

Provide technical and/or economic assistance to 

utilities using low-NOx burners to identify and 

implement cost-effective process modifications or 

new equipment to reduce the carbon content of 

fly ash.

Technical

Lack of consistency and quality in the production of fly 

ash has resulted in limited use in the high-value readymix concrete market. The priority at a coal-fired 

power plant will always be on producing electricity, 

not ash. A change in the combustion process, such as 

the type of coal burned, results in a change in ash 

quality, making it difficult to produce a consistent 

product.

Taking into account the power plant’s priority of 

generating electricity, the program could facilitate 

formal training programs to teach plant operators 

about the co-product value of producing 

consistent-quality fly ash.

Educational

While quality and consistency of fly ash are legitimate 

concerns of end-users, in some cases, negative 

perceptions toward CCP use are unwarranted. Negative 

perceptions can often be attributed to a single 

experience using CCPs in a project that failed, even if 

CCPs were not the cause of the failure. For example, 

at one time, the Austin, TX concrete market almost 

turned to an all-cement market because of one misuse 

resulting from a lack of education about the material. 

Dissemination of objective, scientific material to 

educate potential end users. (EPA has addressed 

this through C

2P2 and other activities).

Sources:

1. U.S. Department of Energy, National Energy Technology Laboratory, “General Summary of State Regulations,” accessed at

http://www.netl.doe.gov/E&WR/cub/states/select_state.html.

2. Energy and Environmental Research Center, “Barriers to the Increased Utilization of Coal Combustion/Desulfurization By-Products by 

Government and Commercial Sectors--Update 1998,” EERC Topical Report DE-FC21-93MC-30097--79, July 1999.

3. ACAA, 2008, “Frequently Asked Questions,” accessed Nov. 19, 2010 at 

http://acaa.affiniscape.com/displaycommon.cfm?an=1&subarticlenbr=5.

4. Schwartz, Karen D. “The Outlook for CCPs,” Electric Perspectives, July/August 2003.

5. Energy & Environmental Research Center, University of North Dakota, “Review of Florida Regulations, Standards, and Practices Related to 

the Use of Coal Combustion Products: Final Report,” April 2006, accessed at http://www.undeerc.org/carrc/Assets/TBFLStateReviewFinal.pdf.

6. Energy & Environmental Research Center, University of North Dakota, “Review of Texas Regulations, Standards, and Practices Related to 

the Use of Coal Combustion Products: Final Report,” January 2005, accessed at

http://www.undeerc.org/carrc/Assets/TXStateReviewFinalReport.pdf.

Exhibit 5-1 outlines a number of economic and non-economic factors that may limit the increased 

beneficial use of CCPs. The economic factors primarily relate to transportation costs and the price of 

virgin materials; a critical limitation of the market for CCPs may be the regional nature of the coalburning industry and the extent to which CCPs can find viable markets competing with virgin materials 

within an economically viable distance.
5-3

Several of the non-economic issues presented in Exhibit 5-1 may also limit the expansion of CCP 

beneficial use, if, for example, new uses and new markets require changes in state policies governing 

CCP use. In response, targeted efforts among states to harmonize policies regarding beneficial use of 

CCPs could result in expansion of certain uses of CCPs.

To effectively describe impacts associated with SMM programs and goals, it is important to develop 

scenarios that correctly identify the limits of existing markets, and calculate the quantitative impact on the 

use of CCPs in different applications. In addition, scenarios should incorporate SMM priorities in order 

to better predict which uses and markets are likely to expand. At this time, data on market limitations and 

on program priorities and goals are not refined enough to inform a detailed program analysis. However, 

spatial information about coal-fired power plants and new data on emerging markets may be sufficient to 

support an analysis in the near future. The result could be a set of scenarios that pinpoints specific uses 

for CCPs that are likely to grow and notes regional and national limits for certain applications.

Structural Changes to the Market

In addition to changes related to market trends and program activities, beneficial use scenarios must, in 

some cases, reflect significant changes to the market, such as large-scale technology shifts that might 

affect demand for or production of CCPs. In addition, for materials frequently used in construction, 

unexpected events such as large storms or terrorist attacks may result in sudden, regional changes in 

demand if, for example, large quantities of materials are needed for reconstruction or if coal-fired power 

plant operations change significantly as a result of a regional event. 

Since these events are by definition unpredictable, it is important to identify methods for analyzing 

impacts if and when they occur. In particular, analyses that clearly identify the current regional market 

conditions (e.g., oversupply, strong demand) would provide a useful starting point for analysis of 

unexpected market shifts.

ATTRIBUTION OF IMPACTS TO EPA PROGRAMS

The factors affecting increased beneficial use also link to the issue of attributing changes in beneficial use 

markets or behavior to specific EPA initiatives. The issue of attribution is complex, and in many cases 

the data necessary to support a clear attribution of impacts are not available. Particularly in the case of 

voluntary programs, it is often difficult to attribute changes in behavior (or a proportion of the change in 

behavior) to specific EPA activities. For example, changes in recycling or source reduction may be due 

to outside forces (i.e., market dynamics), multiple government programs, or a combination of both. 

One starting point in addressing the attribution of benefits to EPA activities is an examination of existing 

information and methods describing the performance of target EPA programs and overall trends in 

beneficial use. Linking program activity with market trends can, on a qualitative basis, provide an 

indication of whether the program is having an effect. This initial scoping exercise can then be 

supplemented with the development of specific program scenarios that endeavor to quantify incremental 

beneficial use levels attributable to EPA's initiatives. In other cases, it may be necessary to start with the 

assumption that all costs and all benefits are related to EPA activities, and adjust that assumption as 

programs mature and data become available.
5-4

A full-scale, defensible approach to attribution of voluntary program impacts, however, requires a clear 

understanding of both the specific activities undertaken by the program and the differences between 

behavior of program participants and those who do not participate. This information can sometimes be 

obtained or identified through broadly collected data that includes both participants and non-participants 

(e.g., the Biennial Report or the Toxics Release Inventory). In other cases, behavioral research can help 

predict effective response rates to different types of programs. Exhibit 5-2 outlines the process for a fullscale assessment of attribution.

EXHIBIT 5-2: OUTLINE TO ATTRIBUTE VOLUNTARY PROGRAM IM PACTS

STEP 1: ASSESS THE MARKET FAILURE BEING ADDRESSED

 Identify and describe specific market failure of interest

Example: material with market value being disposed as waste

 Evaluate size of market failure: evaluation of total quantity affected, current recovery and management, 

potential economically feasible recovery

 Identify key behavior changes necessary to address market failure

 Identify programs in place to address market failure, including Federal, State, local, and private efforts.

STEP 2: DESCRIBE IN DETAIL EACH EPA PROGRAM WORKING ON THE “ ISSUE”

 Summarize program goals, structure, policy leverage points using program evaluation methodologies.

 Identify, for each relevant program, current and intended participants, key resources available, actions taken 

by participants, timeline for behavioral change, and link between activities and behavioral change. 

STEP 3: IDENTIFY AVAILABLE DATA ON EPA AND OTHER EFFORTS

 Quantitative estimates of recent trends in target behavior, specific estimates of recent changes in behavior 

among EPA program members and non-members, and research on response rates for similar programs, 

strategies.

STEP 4: ATTRIBUTION OF IMPACTS TO EPA PROGRAM(S) 

 Refine analysis of data collected in Step 3 to identify changes in behavior among EPA program participants and 

among non-members, expected leverage of EPA activities across federal, state, private programs (e.g., by 

expansion of recycling efforts from pilot programs or harmonization of state regulations as a result of EPA 

information development), and expected leverage of EPA activities over time.

 Identify and correct for independent, confounding market changes that may affect the issue, such as changes in 

virgin raw materials prices due to sudden shortage.

The result of this approach should yield a quantitative estimate of the total extent of changes that can be 

attributed to EPA. Where implementation and/or tracking data are not available, approaches can 

potentially include theoretical estimates reflecting literature on response rates for voluntary activities. As 

necessary, this effort can also provide information to effectively allocate total EPA impacts across 

multiple programs in cases where more than one program is focused on addressing the same market 

failure. In areas where the attribution of outcomes is not possible due to data and methodological 

limitations, program structure and purpose can be revisited with the intent of developing metrics (e.g., for 

PART analysis) that are meaningful in measuring change without attempting to achieve a simplistic 

success metric of “outcome/resources.”

In the absence of specific information on behavior changes among participants and non-participants in 

SMM beneficial use activities, we focus below on total impacts associated with CCP beneficial use. This 

forms an upper bound estimate of the impact of EPA programs related to these materials, but may 

understate total beneficial impacts because not all materials are considered.
5-5

BENEFICIAL IMPACTS ASSOCIATED WITH CURRENT USE OF CCPs

In the absence of defensible beneficial use scenarios for CCPs or a well-supported allocation protocol for 

assigning beneficial use impacts to specific EPA programs, we present a preliminary analysis of the total 

impacts associated with current (baseline) beneficial use patterns. While these impacts do not strictly 

reflect SMM (RCC) program achievements, they represent the best available information on the 

environmental benefits of beneficially using CCPs, and reflect the impacts of all EPA, state, and industry 

efforts to increase CCP use to its 2008 level.

We calculate the beneficial impacts of current beneficial use of CCPs by extrapolating the life cycle 

inventory impacts identified in Chapter 4 to the current quantity of CCPs beneficially used in each 

application as presented in ACAA’s 2008 CCP Survey. We also calculate the beneficial impacts of 

increasing fly ash use in concrete to 18.6 million tons, an increase of roughly half over the 2001 baseline

of 12.4 million tons. Exhibit 5-3 presents the impacts of the beneficial use of fly ash and FGD gypsum 

extrapolated both to current use quantities and the 50-percent increase scenario for use of fly ash in 

concrete.
5-6

EXHIBIT 5-3: EXTRAPOLATED IMPACTS OF THE BENEFICIAL US E OF CCPs

AVOIDED IMPACTS

FLY ASH IN 

CONCRETE 

EXTRAPOLATED 

TO 18.6 MILLION 

TONSa

FLY ASH IN 

CONCRETE 

EXTRAPOLATED TO 

CURRENT USE (12.6

MILLION TONS)b

FGD GYPSUM IN 

WALLBAORD 

EXTAPOLATED TO 

CURRENT USE (8.5

MILLION TONS)c

PARTIAL SUM OF 

CURRENT USE 

BENEFICIAL 

IMPACTSd

ENERGY USE

NONRENEWABLE ENERGY (MJ)e 99.7 billion 67.5 billion 11.3 billion 78.8 billion

RENEWABLE ENERGY (MJ)f 0 0 124.2 million 124.2 million

TOTAL PRIMARY ENERGY (MJ) 99.7 billion 67.5 billion 11.4 billion 78.9 billion

TOTAL PRIMARY ENERGY (BTU) 95 trillion 64 trillion 12 trillion 76 trillion

TOTAL PRIMARY ENERGY (US$)g 438.8 million 297.1 million 184.9 million 482 million

WATER USE 

TOTAL WATER USE (LITERS) 12.8 billion 8.7 billion 759.3 billion 768 billion

TOTAL WATER USE (US$)

h 8.1 million 5.5 million not valued >5.5 million

GREENHOUSE GAS EMISSIONS

CO2 (MT) 18.5 million 12.5 million 703,484 13.2 million

METHANE (MT) 15,700 10,600 1,500 12,100

METRIC TONS CO2 EQUIVALENTi 18.8 million 12.8 million 703,484 13.5 million

METRIC TONS CARBON EQUIVALENT 

(MTCE)j 5.1 million 3.5 million 191,859 3.7 million

AIR EMISSIONS

CO (MT) 25,600 17,400 300 17,700

NOx (MT) 49,900 33,800 1,300 35,100

SOx (MT) 45,600 30,900 1,600 32,500

PARTICULATES GREATER THAN PM10

(MT) 0 0 10,300 10,300

PARTICULATES LESS THAN OR EQUAL 

TO PM10 (MT) 100 100 4,000 4,100

PARTICULATES UNSPECIFIED (MT) 44,200 29,900 0 29,900

MERCURY (KG) 1,400 1,000 8 1,000

LEAD (KG) 0 0 300 300

WATERBORNE WASTES

SUSPENDED MATTER (KG) 9.1 million 6.2 million 0.1 million 6.3 million

BIOLOGICAL OXYGEN DEMAND (KG) 0.4 million 0.3 million 0.2 million 0.5 million

CHEMICAL OXYGEN DEMAND (KG) 0.9 million 0.6 million 0.2 million 0.8 million

COPPER (G) 0 0 17,000 17,000

MERCURY (G) 0 0 460 460

LEAD (G) 0 0 49,000 49,000

SELENIUM (G) 0 0 52,000 52,000

NON-HAZARDOUS WASTE (KG)k 0 0 0 0
5-7

AVOIDED IMPACTS

FLY ASH IN 

CONCRETE 

EXTRAPOLATED 

TO 18.6 MILLION 

TONSa

FLY ASH IN 

CONCRETE 

EXTRAPOLATED TO 

CURRENT USE (12.6

MILLION TONS)b

FGD GYPSUM IN 

WALLBAORD 

EXTAPOLATED TO 

CURRENT USE (8.5

MILLION TONS)c

PARTIAL SUM OF 

CURRENT USE 

BENEFICIAL 

IMPACTSd

Notes:

a. We extrapolate the incremental impacts (i.e., impacts associated with use of 1 ton fly ash) to estimate impacts of increasing 

fly ash use in concrete to18.6 million tons. To extrapolate, we multiply each of the incremental impacts calculated by the 

BEES model by 18.6 million.

b. We extrapolate the incremental impacts (i.e., impacts associated with use of 1 ton fly ash) to estimate the impacts of 

current beneficial use of fly ash in concrete (12.6 million tons). The current quantity of fly ash that is beneficially used as a 

substitute for finished portland cement in concrete is reported by ACAA’s 2008 CCP Survey. We multiply each of the 

incremental impacts calculated by BEES by 12.6 million tons to extrapolate these impacts to reflect current use.

c. We extrapolate the incremental impacts (i.e., impacts associated with use of 1 ton FGD gypsum) to estimate the impacts of 

current beneficial use of FGD gypsum in wallboard (8.5 million tons). The current quantity of FGD gypsum that is beneficially 

used as a substitute for finished portland cement in concrete is reported by ACAA’s 2008 CCP Survey. We multiply each of 

the incremental impacts calculated by SimaPro by 8.5 million to extrapolate these impacts to reflect current use.

d. Calculated as the sum of the fly ash and FGD gypsum current use extrapolations.

e. Nonrenewable energy refers to energy derived from fossil fuels such as coal, natural gas and oil.

f. Renewable energy refers to energy derived from renewable sources, but BEES does not specify what sources these include.

g. We monetize energy impacts for fly ash using a price figure ($0.0044/MJ) derived from the average price of purchased 

energy to the cement manufacturing sector in 2006 ($4.36/million BTU), from Table 7.2, accessed on Nov. 16, 2010 at 

http://www.eia.doe.gov/emeu/mecs/mecs2006/2006tables.html. The cost was converted to 2009 dollars using NASA's Gross 

Domestic Product Deflator Inflation Calculator, accessed on April 22, 2010 at http://cost.jsc.nasa.gov/inflateGDP.html. We 

monetize energy impacts for FGD Gypsum using a price/MJ figure ($0.0179/MJ), derived from the average cost of diesel fuel 

in 2009 ($2.467/gallon), assuming 130,500 BTUs/gallon of diesel fuel. Diesel price is 2009 weekly price of on-highway diesel 

accessed on April 22, 2010 at http://tonto.eia.doe.gov/dnav/pet/pet_pri_gnd_dcus_nus_a.htm; diesel energy value 

accessed April 22, 2010 at http://bioenergy.ornl.gov/papers/misc/energy_conv.html.

h. We monetize water impacts using the average cost of water in 2008 ($2.81/KGal) converted to 2009 dollars ($2.87/KGal). 

The 2008 cost of water is taken from NUS Consulting Group, accessed on April 22, 2010 at 

http://www.marketwire.com/press-release/Average-US-Water-Costs-Increase-by-73-903477.htm. The cost was converted to 

2009 dollars using NASA's Gross Domestic Product Deflator Inflation Calculator, accessed on April 22, 2010 at 

http://cost.jsc.nasa.gov/inflateGDP.html.

i. We converted greenhouse gas emissions to tons of CO2 equivalent using U.S. Climate Technology Cooperation Gateway’s 

Greenhouse Gas Equivalencies Calculator accessed on Dec 3, 2010 at http://www.epa.gov/cleanenergy/energyresources/calculator.html. This calculation only includes CO2 and methane.

j. Impacts in MTCE are calculated by dividing the impacts in MTCO2E by 44/12 (the ratio of the molecular weight of carbon 

dioxide to carbon). U.S. EPA, “A Climate Change Glossary,” accessed at http://www.globalwarming.org/node/91. 

k. BEES reports waste as “end of life waste.” In contrast, SimaPro reports “solid waste.” In is not clear if these waste metrics 

are directly comparable as SimaPro does not specify whether “solid waste” refers to manufacturing waste, end-of-life waste, 

or both.

The results show that current beneficial use of fly ash in concrete and FGD gypsum in wallboard results 

in positive environmental impacts. The most significant impacts include energy savings. Energy savings 

associated with the use of fly ash and FGD gypsum totals approximately 78.8 billion megajoules of 

energy (or approximately $482 million in 2009 energy prices). Based on the average monthly 

consumption of residential electricity customers, this is enough energy to power over 2 million homes for 

an entire year.66 

Avoided water use is also significant, totaling 768 billion liters. However, the total water use for FGD 

gypsum in wallboard is dominated by water used in turbines for power generation. Because turbine use is 

not comparable to consumptive use, we value only the 8.7 billion liters associated with cement 

production; this is equivalent to $5.5 million in 2009 water prices, and is roughly equivalent to the annual 

 

66 Based on the assumption that an average residential customer uses 908 kilowatt-hours per month. EIA, “Table 5A. Residential Average Monthly 

Bill by Census Division and State, 2009” accessed Dec. 3, 2010 at www.eia.doe.gov/cneaf/electricity/esr/table5_a.xls.
5-8

water consumption of 4,400 Americans. By comparison, the total water use including turbine use is 

equivalent to annual water consumption of roughly 389,000 Americans.67 

The extrapolated beneficial impacts also include key impacts such avoided greenhouse gas (13.5 million

tons of avoided CO2 equivalent), and avoided air emissions (35,100 metric tons of avoided NOx, and 

32,500 metric tons of SOx). Note that the impacts presented in Exhibit 5-3 represent only a partial

estimate of the total impacts of beneficially using CCPs. Beneficial use of fly ash as a substitute for 

finished portland cement in concrete and FGD gypsum in wallboard accounts for only 35 percent (21.1

million tons) of all beneficially used CCPs in 2008 (or 42 percent if excluding mining applications). 

Economic Distribution of CCP Beneficial Use Impacts 

In addition to an estimate of overall beneficial impacts associated with use of CCPs, we developed a 

screening analysis using the EIO-LCA model to provide insight into the distribution of impacts across 

economic sectors. We modeled the impacts associated with a hypothetical reduction of $1 million of 

demand from the cement manufacture and gypsum mining sectors. From the perspective of energy and air 

emissions, cement manufacturing leads to large impacts, and is in general the largest source of emissions 

across the supply chain. Reducing the amount of cement produced by beneficially reusing products can 

lead to large supply chain-wide reductions of emissions. Comparatively, the impact of the substitution of 

FGD gypsum for virgin gypsum in wallboard manufacturing is less clear, as the EIO-LCA model was not 

able to adequately represent the wallboard sector.

These results and others produced by the model do not affect the total estimate of beneficial impacts 

associated with changes in use of CCPs. However, they indicate the specific sectors, activities, and points 

in the supply chain that may be most important to consider in more detailed analyses of beneficial use 

scenarios. The EIO-LCA model may provide important insights into the success of policies and actions, 

because the model identifies the types of market changes that may result from specific changes in 

practice. EIO-LCA may, therefore, clarify the positive and negative impacts of specific, targeted 

programs and actions on different economic sectors. Appendix D provides a detailed discussion of the 

analysis.

CONCLUSIONS AND NEXT STEPS

This report provides a preliminary assessment of the baseline impacts associated with the beneficial use 

of fly ash and FGD gypsum in 2008. The analysis uses the life cycle-based BEES and SimaPro models, 

coupled with simple monetized estimates of energy and water savings, to estimate the impacts of 

replacing portland cement with fly ash in concrete and virgin gypsum with FGD gypsum in wallboard. 

The most significant impacts include energy savings and water use reductions. Energy savings associated 

with the use of fly ash and FGD gypsum totals approximately 78.8 billion megajoules of energy (or 

approximately $482 million in 2009 energy prices). Based on the average monthly consumption of 

residential electricity customers, this is enough energy to power over two million homes for an entire 

year. Avoided water use totals approximately 768 billion liters, of which at least 8.7 billion liters is 

consumed (equivalent to approximately $ 5.5 million in 2009 water prices).68 This is roughly equivalent 

 

67 Based on 2000 USGS per capita water use estimate of 1,430 gallons per day. Lumia et al., United States Department of the Interior, United 

States Geological Survey, Summary of Water Use in the United States, 2000. 

68 Based on the assumption that an average residential customer uses 920 kilowatt-hours per month. Department of Energy, Energy Information 

Administration, “Table 5A. Residential Average Monthly Bill by Census Division and State, 2008” accessed Nov. 16, 2010 at 

www.eia.doe.gov/cneaf/electricity/esr/table5_a.xls.
5-9

to the annual water consumption of 4,400 Americans.69 The extrapolated beneficial impacts also include 

key impacts such avoided greenhouse gas (13.5 million tons of avoided CO2 equivalent), and avoided air 

emissions (35,100 metric tons of avoided NOx, and 32,500 metric tons of SOx).

This report also presents a distributional screening analysis using the EIO-LCA model that indicates 

significant avoided environmental impacts from reductions in the demand for cement or virgin gypsum 

that are distributed across several economic sectors. From the perspective of energy and air emissions, 

cement manufacturing leads to large impacts, and is in general the largest source of emissions across the 

supply chain. Reducing the amount of cement produced by beneficially reusing products can lead to large 

supply chain-wide reductions of emissions. Comparatively, the impact of the substitution of FGD 

gypsum for virgin gypsum in wallboard manufacturing is less clear.

The preliminary results of this initial analysis suggest that a more detailed evaluation of the beneficial use 

of CCPs could build on these results to assist the Agency in a more specific evaluation of the 

achievements of the SMM program. A more detailed analysis would require:

 The development of realistic and effective beneficial use scenarios that incorporate more detailed 

descriptions of markets, beneficial uses, and policies. Realistic scenarios should reflect key 

market dynamics and limits such as distance to markets and virgin material prices, and be able to 

assess the impacts of these dynamics on the growth potential for specific beneficial uses. For 

example, the limiting transportation distance for the beneficial use of CCPs in road construction 

may be far less then that of gypsum wallboard.

 The development of a methodology to attribute beneficial use impacts to specific EPA/SMM 

efforts and programs. A phased approach may be appropriate. Such an approach could initially 

employ the simple operating assumption that all impacts result from Agency actions. This 

assumption could then be refined to reflect specific Agency strategies, policies, and other efforts, 

and link these, where possible, to specific changes in beneficial use practices and markets. 

 The expansion of the assessment to include additional CCPs and beneficial use applications. This 

analysis only examines the beneficial impacts of substituting fly ash for finished portland cement 

in concrete and substituting FGD gypsum for virgin gypsum in wallboard manufacturing. These 

two processes represent less than 50 percent of the total beneficial use of CCPs. Additional high

volume applications that may be analyzed include: the use of fly ash as a raw feed in cement 

clinker; the use of boiler slag as blasting grit; and the use of various CCPs in structural fill and 

waste stabilization. In addition, the beneficial impacts of lower volume applications may be 

examined in order to identify those that may have potentially high incremental impacts.

 

69 Based on 2000 USGS per capita water use estimate of 1,430 gallons per day. Lumia et al., United States Department of the Interior, United 

States Geological Survey, Summary of Water Use in the United States, 2000. 
R-1

REFERENCES

ACAA (American Coal Ash Association), “2008 Coal Combustion Product (CCP) Production and Use 

Survey,” accessed at http://acaa.affiniscape.com/associations/8003/files/2008_ACAA_CCP_ 

Survey_ Report_FINAL_100509.pdf

ACAA, Coal Combustion Product (CCP) Production and Use Surveys for 2005 to 2007, accessed Oct. 18, 

2010 at http://acaa.affiniscape.com/displaycommon.cfm?an=1&subarticlenbr=3.

ACAA (American Coal Ash Association), 2006a, Dave Goss, Personal Communication, March 2006.

ACAA (American Coal Ash Association), 2006b, Dave Goss, Personal Communication, April 2006.

ACAA (American Coal Ash Association), 2006c, Dave Goss, Personal Communication, May 2006.

ACAA (American Coal Ash Association), 2006c, Dave Goss, Personal Communication, November 2006.

ACAA (American Coal Ash Association), 2008, “Frequently Asked Questions,” accessed Nov. 19, 2010 

at http://acaa.affiniscape.com/displaycommon.cfm?an=1&subarticlenbr=5.

American Foundry Society (AFS), 2007, “Foundry Industry Benchmarking Survey.”

Caltrans (California Department of Transportation), 2006, Tom Pyle, Personal Communication, 

November 2006.

DOT (U.S. Department of Transportation), 2006, John D’Angelo, Personal Communication, March 2006.

Edgar G. Hertwich, Sarah F. Mateles, William S. Pease, Thomas E. McKone, 2001, Environmental 

Toxicology and Chemistry 20(4):928-939.

EIA (Energy Information Administration), “Table 5A. Residential Average Monthly Bill by Census 

Division and State, 2008” accessed Nov. 16, 2010 at 

www.eia.doe.gov/cneaf/electricity/esr/table5_a.xls.

EIA, 2010, “Annual Energy Outlook 2010 with Projections to 2035: Electricity Demand,” accessed 

October 25, 2010 at http://www.eia.doe.gov/oiaf/aeo/electricity.html. 

EIA, 2010, “Figure 3. Electric Power Sector Consumption of Coal by Census Region, 2009,” accessed 

Oct. 31, 2010 at http://www.eia.doe.gov/cneaf/coal/page/special/fig3.html

EIA, 2010, “Net Generation by Energy Source: Total (All Sectors),” accessed October 25, 2010 at 

http://www.eia.doe.gov/cneaf/electricity/epm/table1_1.html.

EIA (Energy Information Administration), 2007, “U.S. Coal Consumption by End-Use Sector,” 

http://www.eia.doe.gov/cneaf/coal/quarterly/html/t28p01p1.html.

Electric Power Research Institute, 1999, Environmental Focus: Flue Gas Desulfurization By-Products,

BR-114239.

Electric Power Research Institute, 2006, “Coal Combustion Product Use,” accessed at 

http://www.epri.com/Portfolio/product.aspx?id=2065&area=50.

Energy and Environmental Research Center, 1999, “Barriers to the Increased Utilization of Coal 

Combustion/Desulfurization By-Products by Government and Commercial Sectors--Update 

1998,” EERC Topical Report DE-FC21-93MC-30097--79, July 1999.
R-2

Energy & Environmental Research Center, 2006, University of North Dakota, “Review of Florida 

Regulations, Standards, and Practices Related to the Use of Coal Combustion Products: Final 

Report,” University of North Dakota, April 2006, accessed at 

http://www.undeerc.org/carrc/Assets/TB-FLStateReviewFinal.pdf.

Energy & Environmental Research Center, 2005, University of North Dakota, “Review of Texas 

Regulations, Standards, and Practices Related to the Use of Coal Combustion Products: Final 

Report,” accessed at http://www.undeerc.org/carrc/Assets/TXStateReviewFinalReport.pdf.

EPA (U.S. Environmental Protection Agency), 2010, “Boiler Slag,” accessed at 

http://www.epa.gov/osw/conserve/rrr/imr/ccps/boilslag.htm.

EPA (U.S. Environmental Protection Agency), 2010, “Coal Combustion Residuals – Proposed Rule,” 

accessed Nov. 17, 2010 at http://www.epa.gov/osw/nonhaz/industrial/special/fossil/ccrrule/index.htm.

EPA (U.S. Environmental Protection Agency), 2010, “Hazardous and Solid Waste Management System; 

Identification and Listing of Special Wastes; Disposal of Coal Combustion Residuals From 

Electric Utilities; Proposed Rule,” 75 FR 118, June 21, 2010.

EPA (U.S. Environmental Protection Agency), 2010, “Regulatory Impact Analysis for EPA’s Proposed 

RCRA Regulation Of Coal Combustion Residues (CCR) Generated by the Electric Utility 

Industry,” EPA-HQ-RCRA-2009-0640-0003, April 30, 2010.

EPA (U.S. Environmental Protection Agency), 2006, “About C2P

2

,” accessed at 

http://www.epa.gov/epaoswer/osw/conserve/c2p2/about/about.htm. 

EPA (U.S. Environmental Protection Agency), 2006, "Advisory on EPA's Superfund Benefits Analysis," 

EPA-SAB-ADV-06-002.

EPA (U.S. Environmental Protection Agency), 2005, Using Coal Ash in Highway Construction: A Guide 

to Benefits and Impacts, EPA-530-K-05-002, April 2005.

EPA (U.S. Environmental Protection Agency), 2003, "Underground Storage Tanks (UST) Cleanup & 

Resource Conservation & Recovery Act (RCRA) Subtitle C Program Benefits, Costs, & Impacts 

(BCI) Assessments: An SAB Advisory," EPA-SAB-EC-ADV-03-001

EPA (U.S. Environmental Protection Agency), 1999, Report to Congress: Wastes from the Combustion of 

Fossil Fuels, Vol. II, EPA-530-R-99-010, March 1999.

Hassett, David J., Debra F. Pflughoeft-Hassett, Dennis L. Laudal, and John H. Pavlish, 1999, Mercury 

Release from Coal Combustion ByProducts to the Environment.

Hendrickson, Chris, Lester Lave, and H. Scott Matthews, 2006, Environmental Life Cycle Assessment of 

Goods and Services, Resources for the Future: Washington, DC, 2006.

Lumia, Deborah, Kristin Linsey, and Nancy Barber, United States Department of the Interior, United 

States Geological Survey, Summary of Water use in the United States, 2000. 

Miller, Cheri, Gypsum Parameters, Presentation at WOCA Short Course: "Strategies for Development of 

FGD Gypsum Resources."

Portland Cement Association, 2006, “FAQ: Cement Supply Shortage,” accessed at

http://www.cement.org/pca/shortageQA.asp. 
R-3

Price, Jason and Mark Ewen, Industrial Economics, Inc. Memorandum to Lyn Luben, EPA, “Impact of 

CAIR and CAMR on the Quantity and Quality of Coal Combustion Fly Ash Generated by 

Affected Facilities,” December 1, 2006.

Sanchez, F. et al, 2006, “Characterization of Mercury-Enriched Coal Combustion Residues from Electric 

Utilities Using Enhanced Sorbents for Mercury Control,” EPA-600/R-06/008, accessed Nov. 17, 

2010 at http://www.epa.gov/ORD/NRMRL/pubs/600r06008/600r06008.pdf.

Schwartz, Karen D, 2003, “The Outlook for CCPs,” Electric Perspectives, July/August 2003.

Schueck, Joseph et al, 2001, “The Use of FBC Ash for Alkaline Addiiton at Surface Coal Mines,” 2002 

International Ash Utilization Symposium, accessed Nov. 19, 2010 at 

http://www.flyash.info/2001/mining1/49schue.pdf.

Sheikholeslami, Bizhan, Wisconsin Department of Natural Resources, 2006, Personal Communication.

Stein, Antoinette, 2006, State of California Department of Health Services, Personal Communication.

U.S. Department of Energy, National Energy Technology Laboratory, “General Summary of State 

Regulations,” accessed at http://www.netl.doe.gov/E&WR/cub/states/select_state.html.

US EPA, “Characterization of Building-Related Construction and Demolition Debris in the United 

States” and “Characterization of Road-related Construction and Demolition Debris in the United 

States,” 2005. (Note that these documents were preliminary at the time of this Report and were 

undergoing review).

US EPA, “Draft National Priority Trends Report (1999-2003) Fall 2005,” as reported in the NPEP GPRA 

2008 database of TRI data from 1998-2003.

USGS, 2010, “2008 Minerals Yearbook: Gypsum [Advance Release],” accessed Nov. 20, 2010 at 

http://minerals.usgs.gov/minerals/pubs/commodity/gypsum/myb1-2008-gypsu.pdf.

USGS, 2010, “2008 Minerals Yearbook: Lime [Advance Release],” accessed Nov. 20, 2010 at 

http://minerals.usgs.gov/minerals/pubs/commodity/lime/myb1-2008-lime.pdf.

USGS, 2010, “2008 Minerals Yearbook: Sand and Gravel, Construction [Advance Release],” accessed 

Nov. 20, 2010 at http://minerals.usgs.gov/minerals/pubs/commodity/sand_&_gravel_

construction/myb1-2008-sandc.pdf.

USGS, 2010, “Mineral Commodity Summaries: Cement, 2010,” accessed Nov. 20, 2010 at 

http://minerals.usgs.gov/minerals/pubs/commodity/cement/mcs-2010-cemen.pdf

We Energies, 2007, Tom Jason, Personal Communication, November 2006.

Wisconsin Department of Natural Resources, 2006, Bizhan Sheikholeslami

Western Region Ash Group, “Applications and Competing Materials, Coal Combustion Byproducts,” 

accessed at http://www.wrashg.org/compmat.htm
APPENDIX A | KEY BENEFICIAL USE APPLICATIONS FOR CCPS
A-1

EXHIBIT A-1 KEY BENEFICIAL US E APPLICATIONS FOR CCPs (2008)

BENEFICIAL USE APPLICATION 

AND INDUSTRY FLY ASH

BOTTOM 

ASH

FGD 

GYPSUM

FGD 

MATERIAL 

WET 

SCRUBBERS

FGD 

MATERIAL 

DRY 

SCRUBBERS

FGD 

OTHER

BOILER 

SLAG FBC ASH PRODUCT SUBSTITUTES

Concrete 12,592,245 720,948 675,505 0 22,577 0 0 4,341 Cement, Silica fume, Furnace slag

Cement additive 3,174,264 610,194 413,740 0 0 0 0 0 Clay, Soil, Shale, Gypsum 

Flowable fill 74,794 0 0 0 18,338 0 0 0 Soil, Sand, Gravel, Cement

Structural fill 8,012,825 2,996,388 0 0 130,566 106,526 178,363 76,579 Sand, Gravel, Soil, Aggregate 

Road base 1,027,568 767,013 0 0 0 0 0 7,444 Cement, Lime, Aggregate 

Soil stabilizer 627,810 431,664 0 0 60,115 0 0 132,379 Cement, Lime, Aggregate

Mineral filler in asphalt 7,781 257,806 0 0 0 0 0 0 Sand 

Snow and ice control 0 699,561 0 0 0 0 1,352 0 Sand

Blasting grit 84,881 66,670 0 0 0 0 1,486,316 0 Sand 

Mine reclamationa 960,911 63,648 0 685,104 109,641 0 3,021 8,643,947 Soil

Wallboard 0 0 8,533,732 0 0 0 0 0 Natural gypsum

Waste stabilization 2,923,592 84,901 744,592 0 1,221 30,240 0 0 Cement, Lime, Cement kiln dust

Agriculturalsoil amendment 35,340 3,771 278,875 0 2,877 0 0 0 Liming agents

Manufactured aggregate 154,992 727,048 0 0 0 0 19,422 0 Sand, gravel, aggregate 

Miscellaneous/other 465,271 646,643 6,900 0 0 0 1,418 0

CCP Category Use Totals 30,142,274 8,076,255 10,653,344 685,104 345,335 136,766 1,689,892 8,864,690

CCP Utilization Rate 42% 44% 60% 5% 25% 9% 83% 93%

a. EPA does not consider large fill operations such as use in mine reclamation a beneficial use. EPA, 2010, “Hazardous and Solid Waste Management System; Identification and 

Listing of Special Wastes; Disposal of Coal Combustion Residuals From Electric Utilities; Proposed Rule,” 75 FR 118 (June 21, 2010), p. 35148.

Sources: 

1. ACAA, “2008 Coal Combustion Product (CCP) Production and Use Survey,” accessed Oct. 18, 2010 at 

 http://acaa.affiniscape.com/associations/8003/files/2008_ACAA_CCP_Survey_Report_FINAL_100509.pdf

2. Western Region Ash Group, “Applications and Competing Materials, Coal Combustion Byproducts,” accessed at http://www.wrashg.org/compmat.htm.
APPENDIX B | USE OF LIFE CYCLE ASSESSMENT IN AN 

EVALUATION OF ECONOMIC BENEFITS
B-1

Life cycle assessment (LCA) inventory analyses of the type presented in this report deliver 

incremental changes in physical inputs, outputs, and energy arising from management or 

regulatory changes to an industrial production process. This discussion addresses the following 

issues: how does LCA relate to economic analysis of benefits, and how are economic impacts 

derived from changes in “physical inventory,” such as energy use and alternative waste streams?

RELATIONSHIP BETWEEN LCA AND ECONOMIC ANALYSIS OF 

BENEFITS

LCA is a performance assessment tool – a method to depict physical outcomes that can be used to 

assess impacts and measure progress over time. And because LCA is a systems approach to 

assessment, it offers significant improvement over less comprehensive techniques. However, in 

economic terms, LCA is only one component of a true analysis of benefits – albeit a central 

component. 

Consider the architecture of an economic benefit assessment. At the “front end” lies a set of 

economic drivers that determine technologies and practices employed by industry. These drivers 

include raw material prices, other input costs (including transport), competitive factors, 

regulation, technology, and taxes. EPA programs such as SMM work to facilitate changes in the 

economic drivers of waste generation, handling, and disposal (e.g., a change in tipping fees, 

tighter permit requirements on landfills, benefits to participation in beneficial use programs, etc.). 

Changes in these economic drivers can be expected to lead to changes in the physical system of 

production. In other words, the physical system and its outputs are properly thought of as the 

end product of a set of economic incentives (prices) and constraints (technology). 

LCA depicts production as a system of sometimes reinforcing, sometimes counteracting physical 

outcomes. In particular, it allows the analyst to predict the incremental physical consequences of 

a change in disposal practices, technology, or price incentives. Any change in the physical 

system leads to a corresponding cascade of system changes – as inputs are substituted, exposure 

pathways are changed, and technology adapts. LCA produces the net result of these various 

changes and, thus, the true, incremental effect on physical outputs.70

Deriving an incremental physical effect from a complex system is difficult enough. As the 

agency seeks performance measures to satisfy its GPRA and PART requirements, LCA is a 

natural starting point. It demands systems thinking, properly views outcomes as changes to 

baseline conditions, identifies tradeoffs, and yields concrete, measurable metrics. LCA can tell us 

who and what will be affected by changes in industrial practice, and even where changes are 

likely to occur. 

However, while LCA is a fundamental building block of benefit assessment, LCA does not itself 

yield the social benefits and costs of industrial change. To do that, we must apply economic 

valuation techniques to the physical outputs of LCA analysis. 

 

70

 For example, the PaLATE model generates incremental effects on physical outputs arising from changes in roadway materials. 
B-2

Economic Assessment is desirable because we don’t really care about physical outcomes, we care 

about what those outcomes imply for human well-being. Another way of putting this is, how do 

we compare the “apples” of one change to the “oranges” of another?71 Also, how do we compare 

a given “small” physical gain in one waste to a “large” reduction in another. In physical terms, 

we might be tempted to say that the large gain outweighs the small loss. Of course, small 

physical changes can have large health and environmental consequences with large economic 

ramifications (think of the effect of radiation or toxics on health). 

To understand how energy and raw materials use and emissions of different kinds affect wellbeing we must make a set of additional “translations.” A physical change in lead concentrations 

leads, via ecological and epidemiological processes, to changes in human exposure. Changes in 

exposure lead to morbidity and mortality effects. Morbidity and mortality effects have social 

benefits and costs.72 Those benefits and costs are the ultimate goal of our analysis. In another 

example, the effect of water consumption on well-being depends upon the location, timing, and 

quality of the water that is consumed. The value of that water depends on how it would 

otherwise be used – for human consumption, industrial uses, habitat support, irrigation, etc. LCA 

tells us little, if anything, about these relationships. Thus, LCA may tell us relatively little about 

the actual welfare effects of changes in industrial process. 

Unfortunately, the translation of physical changes into economic outcomes is costly, difficult, and 

often controversial when applied to human health or environmental outcomes. As the report 

notes earlier, “with the exception of water and energy savings for which current price data are 

available, we do not calculate these benefits in dollar terms because monetizing involves complex 

valuation procedures.” Putting economic value on even a small set of physical impacts can be a 

significant and expensive proposition.

Accordingly, LCA should be regarded, not only as a necessary ingredient, but also as a practical 

alternative to real benefit assessment. While economic benefits are the ultimate performance 

measure, businesses and governments routinely rely on simpler – though imperfect – proxies to 

facilitate management and performance assessment. As proxies, LCA outputs are a legitimate 

and defensible compromise. 

INVENTORY CHANGES AND WELFARE: THE TRANSLATION OF LCA 

OUTPUTS TO ECONOMIC IMPACTS

There are two basic steps that must be employed to translate LCA-generated inventories into 

social benefits. The first is the translation of LCA inventories into “final economic goods.” The 

second is the valuation of those final goods. 

Mapping LCA inventories into final economic goods

In general, changes in LCA physical inventories will generate a set of corresponding changes in 

other physical conditions relevant to human well-being. Even before economic valuation occurs, 

these follow-on physical implications must be assessed. For instance, to value changes in 

 

71 Hendrickson, Lave, and Matthews (2006) (“A typical [Life Cycle Inventory] of air pollution results in estimates of conventional, 

hazardous, toxic, and greenhouse gas emissions to the air. Even focused on this small subset of environmental effects, it is unclear 

how to make sense of the multiple outputs and further how to make a judgment as to tradeoffs or substitutions of pollutants among 

alternative designs.”), 29.

72 Some in the LCA community refer to this as an LCA impact analysis, as opposed to the preceding LCA inventory analysis. Inventory 

analyses are those most commonly referred to as LCA. See Graedel and Allenby (1995).
B-3

mercury releases, it is important to know how increased or decreased mercury emissions interact 

with exposure pathways to affect body burdens and human health. An LCA inventory does not 

address this issue; an analysis of epidemiology and exposure is required. Similarly, hydrological 

analysis is required to determine how a reduction in water usage translates into water availability 

in different locations and at different times. Further, ecological analysis must be deployed to 

answer questions such as “what is the effect of greater water availability on species and habitats?” 

The point is that benefit assessment requires synthetic systems thinking of an order at least as 

great as the original LCA analysis.73 

The goal of these biophysical and epidemiological translations is to translate LCA inventory 

results to outcomes with direct human impact – health effects or the availability of water in a 

particular stream at a particular time.

In the human health realm, toxic wastes or air quality burdens must be evaluated in terms of fate, 

transport, and deposition models. Human health models then translate depositions into human 

health impacts via epidemiological analysis (e.g., dose-response relationships). EPA is relatively 

sophisticated in its use of such models, owing to decades of experience with air quality regulation 

and the analysis of economic effects arising from air quality-related health assessments. 

In the ecological realm, these kinds of translations are underdeveloped. The agency is aware of 

this – the conclusion has been drawn from several recent SAB reports.74 The analysis of 

ecological benefits is clarified by drawing distinctions between ecosystem processes and 

functions and the “final” outcomes of those processes (denoted here as “final ecosystem goods.” 

Ecosystem processes and functions are the biological, chemical, and physical interactions 

associated with ecological features such as surface water flows, habitat types, and species 

populations. These functions are the things described by biology, atmospheric science, 

hydrology, and so on. 

Final ecosystem goods arise from these components and functions but are different: they are the 

aspects of the ecosystem that are directly valued by people. The benefits of nature include many 

forms of recreation, aesthetic enjoyment, commercial and subsistence harvests, damage 

avoidance, human health, and the intangible categories mentioned earlier. Final ecosystem goods 

are the aspects of nature used by society in order to enjoy those benefits. 

Part of the above definition is particularly important: namely, that ecosystem services are “final.” 

Final goods are the things people actually make choices about. For an angler, these end products 

include a particular lake or stream and perhaps a particular species population in that water body. 

The choices involved include which lake, what kind of fish, what kind of boat (if any) and tackle 

to use, and how much time spent getting to and from the site. Valuation is about choices (is one 

thing better than another) and choices are the only thing economists can use to establish economic 

value. Environmental benefit assessment places values on the things people and households make 

actual choices about – the “final goods” of nature. It is very important to emphasize that many 

 

73 For an example of a full social cost & benefit analysis see Krupnick and Burtraw (1997).

74 For example, this conclusion has been drawn from several recent SAB reports, including EPA-SAB. 2003. "Underground Storage Tanks 

(UST) Cleanup & Resource Conservation & Recovery Act (RCRA) Subtitle C Program Benefits, Costs, & Impacts (BCI) Assessments: An 

SAB Advisory." (EPA-SAB-EC-ADV-03-001) and "Advisory on EPA's Superfund Benefits Analysis." (EPA-SAB-ADV-06-002). In addition, the 

SAB Committee on Valuing the Protection of Ecological Systems and Services is currently examining methods for addressing these 

limitations.
B-4

other aspects of nature are valuable, but not capable of being valued in an economic sense –

because they are not subject to social or individual choices.

Ecosystem production functions are the relationships that translate LCA inventory changes into 

final ecosystem goods. One characteristic of these production functions is particularly worthy of 

note: ecological production functions are dependent upon space and landscape. Location- and 

scale-specificity are core characteristics of modern ecology. For example, the quality of a habitat 

asset can be highly dependent on the quality and spatial configuration of surrounding land uses. 

The ability of areas to serve as migratory pathways and forage areas typically depends on 

landscape conditions over an area larger than habitats relied upon directly by the migratory 

species. The contiguity of natural land cover patches has been shown for many species to be an 

indicator of habitat quality and potential species resilience. Hydrological analysis is yet another 

field that has long recognized the importance of relationships between landscape features. The 

nature of surface water flows, aquifer structures, and surface-groundwater interactions are 

dependent upon linked physical relationships across the landscape. 

For ORCR to move toward measurement of ecosystem impacts arising from beneficial use, or 

any other change in waste management practices, the ability to translate LCA inventory changes 

into final ecosystem good changes requires the development of spatial ecological modeling. 

Space and scale are important to the valuation of final ecosystem goods, as well. 

Assigning value to changes in final ecological goods

The value of an ecosystem good is typically location-dependent. The value of a car is not closely 

related to whether it is located in California or New Jersey. This is not the case with ecological 

goods. The benefits of damage mitigation, aesthetic enjoyment, and recreational and health 

improvements depend on where—and when—ecosystem services arise relative to complementary 

inputs and substitutes. Also, the ecological asset interactions that enhance or degrade service 

flows are highly landscape-dependent. Accordingly, it is necessary to spatially define “service 

areas.” An unfortunate reality is that these will be different for every identified ecosystem service. 

Boundaries are needed to define the likely users of a service, areas in which access to a service is 

possible, and the area over which services might be scarce or have substitutes. This issue is well 

known in environmental economics (Smith and Kopp 1996). For example, a key methodological 

issue in any econometric recreational benefits study is the determination of the appropriate choice 

set facing recreators.

While market prices can be assumed to be largely constant within a single market, there is no 

arbitrage to ensure this condition for the implicit prices of environmental resources. Also, many 

ecological services are best thought of as differentiated goods with important place-based quality 

differences. As noted earlier, the biophysical characteristics of ecosystems are highly landscapedependent. The same is true of ecological services’ social benefits. Accordingly, willingness to 

pay for ecological services is best represented by a hedonic price function, not a single price.

An intermediate step: benefit indicators as an alternative to full 

valuation 

The spatial factors that affect ecosystem goods’ value create a problem for analysts. Benefit 

estimates from one study in one location cannot be transferred to other sites. In practical terms, 

this means that ecosystem valuation is expensive, time-consuming, and difficult. Problemspecific valuation will be impractical for most regulatory applications. 
B-5

In this context, one alternative to full-scale valuation is the use of “benefit indicators” (Boyd 

2004, Boyd and Wainger 2002). The benefits of a given ecosystem good are affected by the 

following: the ecosystem feature’s scarcity, natural and built substitutes, complementary inputs, 

and the number of people in proximity to it. All of these can and should be measured spatially. 

Benefit indicators are map-able, countable landscape features that affect the value of a particular 

ecosystem good. Benefit indicators are an input to a wide variety of tradeoff analysis approaches, 

but do not themselves make or calculate the results of such tradeoffs. First, they can be used as 

ends in themselves as regulatory or planning performance measures. Second, they can be used as 

part of public processes designed to elicit public preferences over environmental and economic 

options – as in mediated modeling exercises or more informal political derivations. Benefit 

indicators are a potentially powerful complement to group decision processes. Third, they can be 

used as inputs to economic and econometric methods such as benefit transfer, or stated preference 

models. In the former, they can be used to calibrate the transfer function. In the latter case, they 

can be used to develop alternative choice scenarios. 

REFERENCES

Boyd, James, “What’s Nature Worth? Using Indicators to Open the Black Box of Ecological 

Valuation,” Resources, 2004.

Boyd, James and Lisa Wainger, “Landscape Indicators of Ecosystem Service Benefits,” 

84 American Journal of Agricultural Economics, 2002.

Graedel, T.E., and B.R. Allenby, Industrial Ecology, Prentice Hall: Englewood Cliffs NJ, 1995.

Hendrickson, Chris, Lester Lave, and H. Scott Matthews, Environmental Life Cycle Assessment 

of Goods and Services, Resources for the Future: Washington, DC, 2006.

Krupnick, Alan and Dallas Burtraw, “Social Costs of Electricity: Do the Numbers Add Up?” 

Resources and Energy 18:4, 1997, 423-466.

Porter, Richard, The Economics of Waste, Resources for the Future: Washington, DC, 2002.

Portney, Paul, “The Price Is Right: Making Use of Life Cycle Analyses,” Issues in Science and 

Technology, 10: 2 Winter, 1993, 69-75. 

Smith, V. Kerry, and Ray Kopp, Valuing Natural Assets: The Economics of Natural Resource 

Damage Assessment, (Resources for the Future: Washington, DC, 1996.
APPENDIX C | ANALYSIS OF BENEFITS USING ALTERNATE LIFE 

CYCLE MODELS
C-1

In the main body of this report, we present an analysis of the life cycle benefits of substituting fly 

ash for finished portland cement in concrete using BEES. For comparative purposes, this 

appendix illustrates the impacts associated with beneficial use of fly ash in concrete that can be 

calculated using two additional life cycle tools: the WARM and EIO-LCA models.

WARM MODEL ANALYSIS

The Waste Reduction Model (WARM) was created by EPA to help solid waste planners and 

organizations estimate greenhouse gas (GHG) emission reductions from several different waste 

management practices.75 WARM calculates GHG emissions for baseline and alternative waste 

management practices, including source reduction, recycling, combustion, composting, and 

landfilling. The user can construct various scenarios by entering data on the amount of waste 

handled by material type and by management practice. WARM then automatically applies 

material-specific emissions factors for each management practice to calculate the GHG emissions 

and energy savings of each scenario. The model evaluates energy use and GHG emissions in 

three stages of the life cycle: (1) raw material acquisition, (2) manufacturing (fossil fuel energy 

emissions), and (3) waste management (carbon dioxide emissions associated with compost, nonbiogenic carbon dioxide and nitrous oxide emissions from combustion, and methane emissions 

from landfills). At each of these points, the study also considers transportation-related energy use 

and GHG emissions. 

The WARM model reports avoided lifecycle GHG emissions in either metric tons CO2 equivalent 

(MTCO2E) or metric tons CO equivalent (MTCOE), as well as energy use in BTUs. In addition, 

the model converts these outputs to equivalent metrics including the equivalent number of cars 

removed from the road in one year, the equivalent number of avoided barrels of oil burned, and 

the equivalent number of avoided gallons of gasoline consumed. Currently, the only CCP 

available for analysis using WARM is fly ash. WARM calculates GHG emissions and energy use 

associated with use of fly ash in concrete as an alternative to landfill disposal. We first use 

WARM to estimate the incremental impacts associated with beneficial use of one ton of fly ash in 

concrete, in comparison to disposing of that ton of fly ash in a landfill. Then, we extrapolate the 

results to estimate benefits associated with beneficially using 18.6 million tons of fly ash in 

concrete.76 

Results

Exhibit C-1 presents the results of the WARM model analysis for the beneficial use of fly ash.77

The WARM model estimates that one ton of fly ash beneficially used in concrete results in 

avoidance of approximately 0.91 MTCO2E of GHG emissions and 5.29 million BTUs of energy 

use. Extrapolating these outcomes to beneficially use of 18.6 million tons of fly ash in concrete

results in savings of approximately 17 million MTCO2E. According to the WARM model, 

 

75 WARM can be accessed at http://yosemite.epa.gov/oar/globalwarming.nsf/WARM?openform. Version 8 of the model was used for this 

analysis. Available information indicates that Version 8 was last updated in August of 2006.

76 WARM allows the user to define key modeling assumptions, such as landfill gas recovery practices and transport distance to MSW 

facilities. For landfill gas (LFG) control, we select the “National Average” setting, which calculates emissions based on the anticipated 

proportion of landfills with LFG control in 2000. For transport distances, we use the default setting (20 miles).

77 It is important to note that the results reported by WARM for avoided greenhouse gas emissions and avoided energy use may not be 

directly comparable to those reported by the BEES model or PALATE model due to differences in the methodologies (including life 

cycle system boundaries) employed by each model.
C-2

beneficially using 18.6 million tons of fly ash results in 98.5 trillion BTUs (103.8 million MJ) of 

avoided energy use. This energy savings is equivalent to 17 million barrels of avoided oil 

consumption, 792 million gallons of avoided gasoline consumption, or a reduction in annual 

energy use by approximately half a million households.

EXHIBIT C-1: WARM RESULTS: IMPACTS OF BENEFICIAL USE OF FLY ASH IN CONCRETE

IMPACT

INCREMENTAL IMPACT OF USING 

1 TON OF FLY ASH

TOTAL IMPACTS OF BENEFICIALLY 

USING 18,600,000 TONSa

GHG EMISSIONS AVOIDED (MTCO2E) 0.91 16.91 million 

AVOIDED ENERGY USE (BTUs)

b

5.29 million

$24.58

98.47 trillion

$457.12 million

EQUIVALENT AVOIDED OIL 

CONSUMPTION (BARRELS)

0.91 17 million

EQUIVALENT AVOIDED GASOLINE 

CONSUMPTION (GALLONS)

42. 59 792 million

EQUIVALENT AVOIDED HOUSEHOLDS’ 

ANNUAL ENERGY CONSUMPTION 

(HOUSEHOLDS)

0.049 0.92 million

Notes:

a. The total impacts represent the difference between beneficially using 18.6 million tons of fly ash in concrete in 

comparison to disposal in a landfill.

b. We monetize energy impacts for fly ash using a price figure ($0.0044/MJ) derived from the average price of 

purchased energy to the cement manufacturing sector in 2006 ($4.36/million BTU), from Table 7.2, accessed on 

Nov. 16, 2010 at http://www.eia.doe.gov/emeu/mecs/mecs2006/2006tables.html. The cost was converted to 2009 

dollars using NASA's Gross Domestic Product Deflator Inflation Calculator, accessed on April 22, 2010 at 

http://cost.jsc.nasa.gov/inflateGDP.html. 

Sources:

1. US EPA, Solid Waste Management and Greenhouse Gases, A Life cycle Assessment of Emissions and Sinks, 2nd 

Edition, May 2002. (EPA530-R-02-006) (WARM Model)

2. US EPA, Background Document for Life cycle Greenhouse Gas Emission Factors for Fly Ash Used as a Cement 

Replacement in Concrete, November 2003. (EPA530-R-03-016)

Limitations and Assumptions 

Although the WARM analysis provides a useful example of the energy use and GHG emissions 

benefits that can be achieved through the beneficial use of fly ash in concrete, it is important to 

recognize some of the key limitations of the work to date:

 Our analysis assumes a 20-mile transport distance from the point of collection to the

landfill or concrete facility. In reality, transport distances may be greater or less than 20 

miles. Adjusting transport distance would effect both GHG emissions and energy use. 

 Emissions factors used in WARM reflect national averages. Our analysis may therefore 

over or under estimate impacts for a specific region or location. In addition, we use a 

national average for landfill gas recovery that may also over or understate emissions for 

a specific landfill. 

 WARM does not specifically calculate impacts on purchased energy. Purchased energy 

impacts may be incorporated into the avoided energy use metric, but this is not clear.
C-3

 WARM reports some environmental impacts in physical quantities (e.g., BTUs energy, 

lbs NOx, etc.), not in monetized dollar effects.

EIO-LCA ANALYSIS

The goal of this task was to do a preliminary assessment of what the baseline energy and air 

pollution effects are for existing cement production, such that any reduction of this demand in 

terms of beneficially used fly ash would lead to reduced impact.

To estimate baseline impacts of cement production, we used the Economic Input-Output Life 

Cycle Assessment (EIO-LCA) model. EIO-LCA was developed at Carnegie Mellon and provides 

the capacity to evaluate economic and environmental effects across the supply chain for any of 

428 industry sectors in the U.S. economy in 2002. EIO-LCA also can represent the supply chain 

use of inputs and resulting environmental outputs across the supply chain by using publicly 

available data sources from the U.S. government. By integrating economic data on the existing 

flow of commerce between commodity sectors with environmental data on releases and material 

flows generated by each sector, it is possible to estimate the additional environmental emissions 

caused by an increase in production within a particular sector, accounting for the supply chain. 

This approach can be used to avoid some of the system boundary limitations of process LCA by 

drawing upon data for the entire economy. The EIO-LCA model includes a variety of such 

impacts for the entire US economy. For a closer look at the model, visit http://www.eiolca.net.

Currently, the EIO-LCA model is in active use. Since 2000, the model has registered over 

900,000 uses (or over 15,000 per month). Of identifiable access sites, educational users are most 

common, but there is substantial use by government agencies, non-profit organizations and 

companies. A surprising number of foreign users exist, suggesting that international comparisons 

are of considerable interest.

Cement Analysis

Specifically within EIO-LCA, industry “Sector #327310: Cement Manufacturing” was selected 

for analysis in the model. This industry comprises establishments primarily engaged in 

manufacturing portland, natural, masonry, pozzolanic, and other hydraulic cements. Cement 

manufacturing establishments may calcine earths or mine, quarry, manufacture, or purchase lime. 

Examples of activities in this sector include the following:

 Cement (e.g., hydraulic, masonry, portland, pozzolana) manufacturing

 Cement clinker manufacturing

 Natural (i.e., calcined earth) cement manufacturing

We ran the EIO-LCA selecting US 2002 as the model, cement manufacturing as the sector, and

one million dollars of economic activity. Exhibit C-2 displays the resulting summary estimates of 

supply-chain wide economic impacts. EIO-LCA is a linear model, thus the estimates scale in a 

constant fashion ($2 million of production would lead to double the results listed below). The 

main point of EIO-LCA is for screening purposes, thus the specific dollar values are less relevant 

than the broad, economy-wide implications that show where less obvious supply chain impacts 

might exist. 
C-4

EXHIBIT C-2: TOP SECTORS THAT SUPPORT CEMENT MANUFACTURING IN THE US IN 2002

(ECONOMIC)

SECTOR

TOTAL

ECONOMIC

$ MILLIONS

VALUE

ADDED

$ MILLIONS

DIRECT

ECONOMIC

%

Total for all sectors 1.98 0.986 76.8

327310 Cement manufacturing 1.02 0.487 99.8

221100 Power generation and supply 0.092 0.063 86.5

550000 Management of companies and enterprises 0.056 0.035 54.0

221200 Natural gas distribution 0.055 0.018 88.1

420000 Wholesale trade 0.044 0.030 54.0

211000 Oil and gas extraction 0.042 0.021 1.54

327992 Ground or treated minerals and earths manufacturing 0.029 0.016 90.2

484000 Truck transportation 0.023 0.010 55.6

230301 Nonresidential maintenance and repair 0.021 0.012 53.0

52A000 Monetary authorities and depository credit intermediation 0.018 0.012 28.2

As shown in the “Total Economic” column of Exhibit C-2, there are significant purchases of 

electricity, oil and gas, etc. across the supply chain. This is due to the recognized significant fuel 

and energy inputs needed to produce cement. Also visible in the top 10 economic purchases are 

purchases from minerals, stone, and coal.

Exhibit C-2 also summarizes which of the purchases are “direct,” meaning those made directly by 

the cement manufacturer. For example, EIO-LCA estimates that 86.5 percent of the electricity 

purchases across the entire supply chain are direct. That means that only 13.5 percent of total 

electricity purchases of cement manufacturing in the supply chain come from all other sectors’ 

purchases of electricity. This would include electricity bought by oil and gas production and 

distribution, stone and coal mining, etc. This amount of direct purchases is a very large amount 

compared to the usual electricity direct purchases that come from other sectors.

EIO-LCA also displays estimates of emissions and energy use across the supply chain, as shown 

in Exhibits C-3 and C-4. Exhibit C-3 summarizes emissions of conventional air pollutants, and is 

sorted by SO2 emissions; these results are from running the US 1997 model, because 

conventional air pollutant figures are not available for the US 2002 model. Most SO2 comes from 

cement manufacturing (and about 15 percent from power generation). About 90 percent of NOx 

and VOC emissions from cement manufacturing come from the cement manufacturing itself, 70

percent of CO from the supply chain production of cement comes from cement manufacturing, 

followed by truck transportation. Ninety percent of PM10 emissions come from cement. In short, 

cement manufacturing itself is a very polluting process, and avoiding emissions from its 

manufacture can have large social benefits.
C-5

EXHIBIT C-3: AIR EMISSIONS OF TOP 10 EMITTING SECTORS THAT SUPPORT CEMENT 

MANUFACTURING IN THE US IN 1997 (SORTED BY SO2 )

SECTOR

SO2

MT

CO

MT

NOX

MT

VOC

MT

LEAD

MT

PM10

MT

Total for all sectors 27.3 20.4 31.7 23.6 0.005 3.96

327310 Cement manufacturing 22.4 14.6 28.6 22.4 0.005 3.48

221100 Power generation and supply 4.44 0.219 2.01 0.019 0.000 0.094

212310 Stone mining and quarrying 0.209 0.391 0.147 0.074 0 0.043

211000 Oil and gas extraction 0.040 0.068 0.030 0.046 0 0.001

221200 Natural gas distribution 0.027 0.001 0.052 0.183 0 0.001

483000 Water transportation 0.024 0.017 0.129 0.124 0 0.012

324110 Petroleum refineries 0.018 0.010 0.004 0.014 0 0.002

213112 Support activities for oil and gas operations 0.016 0.013 0.010 0.004 0 0.002

482000 Rail transportation 0.015 0.032 0.272 0.013 0 0.006

484000 Truck transportation 0.011 3.58 0.258 0.266 0.000 0.006

Exhibit C-4 summarizes supply chain wide use of energy and electricity for producing cement. 

The cement sector consumes about 80 percent of total supply chain primary energy use (and 

almost 90 percent of electricity, as noted above). Other sectors consuming top but less significant 

amounts of energy (in the form of fuels) are power generation and supply and lime and gypsum 

product manufacturing.

EXHIBIT C-4: TOP 10 SECTORS USING ENERGY THAT SUPPORT CEMENT MANUFACTURING

IN 2002 (SORTED BY TOTAL ENERGY USE)

SECTOR

TOTAL

TJ

NON-FOSSIL 

ELECTRICITY 

TJ

Total for all sectors 74.4 6.41

327310 Cement manufacturing 59.7 5.54

221100 Power generation and supply 9.98 0.233

3274A0 Lime and gypsum product manufacturing 0.427 0.036

211000 Oil and gas extraction 0.397 0.039

486000 Pipeline transportation 0.354 0.085

327992 Ground or treated minerals and earths manufacturing 0.352 0.050

484000 Truck transportation 0.295 0.003

324110 Petroleum refineries 0.289 0.010

322130 Paperboard Mills 0.239 0.016

482000 Rail transportation 0.233 0.004
C-6

In summary, from the perspective of energy and air emissions, cement manufacturing leads to 

large impacts, and is in general the largest source of emissions across the supply chain. Reducing 

the amount of cement produced through beneficial use of fly ash can lead to large supply chainwide reductions of emissions.

Gypsum Analysis

Within EIO-LCA, the industry “Sector #212390: Other Nonmetallic Mineral Mining” was 

selected for analysis. This industry is aggregated to include many products and processes (and 

thus is less representative of a specific industry like wallboard manufacture than the sector 

representing cement manufacturing above). This U.S. industry comprises establishments 

primarily engaged in developing the mine site, mining and/or milling, or otherwise beneficiating 

(i.e., preparing) natural potassium, sodium, or boron compounds, phosphate rock, fertilizer raw 

materials, or nonmetallic minerals. There are many products of this industry, a few of which are 

summarized below:

 Borate, natural, mining and/or beneficiating

 Phosphate rock mining and/or beneficiating

 Gypsum mining and/or beneficiating

 Peat grinding

We ran the EIO-LCA selecting the following conditions: US 2002 as the model, other 

nonmetallic mineral mining as the sector, one million dollars of economic activity, and displaying 

results in terms of economic activity. Exhibit C-5 displays the resulting summary estimate of 

supply-chain wide economic impacts. As shown in the “Total Economic” column of Exhibit C-5, 

there are significant purchases of electricity, oil and gas, and construction machinery, etc. across 

the supply chain. This is due to the recognized significant fuel and energy inputs needed to 

produce nonmetallic minerals like gypsum. 
C-7

EXHIBIT C-5: TOP SECTORS THAT SUPPORT NONMETALLIC MINERAL MINING –- AS A 

PROXY FOR GYPSUM MANUFACTURING -- IN THE US IN 2002 (ECONOMIC)

SECTOR

TOTAL

ECONOMIC

$ MILLIONS

VALUE

ADDED

$ MILLIONS

DIRECT

ECONOMIC

%

Total for all sectors 1.92 0.991 77.6

212390 Other nonmetallic mineral mining 0.928 0.473 99.9

211000 Oil and gas extraction 0.096 0.049 68.0

550000 Management of companies and enterprises 0.071 0.044 69.3

221100 Power generation and supply 0.069 0.047 87.5

484000 Truck transportation 0.056 0.025 83.3

541300 Architectural and engineering services 0.038 0.023 65.1

21311A Support activities for other mining 0.037 0.011 91.1

327992

Ground or treated minerals and earths 

manufacturing 0.033 0.018 99.2

221200 Natural gas distribution 0.031 0.010 87.5

420000 Wholesale trade 0.030 0.021 40.7

Exhibit C-5 also summarizes which of the purchases are “direct,” (i.e., those made directly by the 

nonmetallic mineral company). For example EIO-LCA estimates that 77.6 percent of the 

electricity purchases across the entire supply chain of nonmetallic minerals mining are direct. 

That means that only 12.4 percent of total electricity purchases in the supply chain come from all 

other sectors’ purchases of electricity, including well-known electricity intensive sectors like 

manufacturing. This would include electricity purchased by oil and gas production and 

distribution, machinery manufacturing, etc. Note that this level of direct purchases is very large 

compared to the usual electricity direct purchases that come from other sectors.

EIO-LCA also displays estimates of emissions and energy use across the supply chain, as shown 

in Exhibits C-6 and C-7. Exhibit C-6 summarizes emissions of conventional air pollutants, and is 

sorted by SO2 emissions; these results are from running the US 1997 model, because 

conventional air pollutant figures are not available for the US 2002 model. Most (85 percent) of 

SO2 emitted across the supply chain of nonmetallic minerals comes from power generation; less 

than five percent is from the mining of the nonmetallic minerals. Almost half of NOx emissions 

come from power generation, followed by truck and rail transport; less than ten percent is from 

nonmetallic mineral mining. About 80 percent of CO emissions result from truck transportation, 

while less than one percent results from nonmetallic mineral mining. About 40 percent of PM10 

emissions come from nonmetallic mineral mining, followed by about 15 percent from power 

generation. In short, nonmetallic mineral mining itself is a very polluting process, and avoiding 

emissions from its manufacture can have large social benefits, but emissions from energy 

production and transportation are higher in some cases.
C-8

EXHIBIT C-6: AIR EMISSIONS OF TOP 10 EMITTING SECTORS THAT SUPPORT 

NONMETALLIC MINERAL MINING IN THE US IN 1997 (SORTED BY SO2 )

SECTOR

SO2

MT

CO

MT

NOX

MT

VOC

MT

LEAD

MT

PM10

MT

Total for all sectors 3.47 9.41 2.85 1.72 0.000 0.421

221100 Power generation and supply 2.94 0.145 1.33 0.013 0.000 0.062

212390 Other nonmetallic mineral mining 0.151 0.051 0.241 0.656 0 0.169

211000 Oil and gas extraction 0.053 0.089 0.039 0.060 0 0.002

212310 Stone mining and quarrying 0.043 0.080 0.030 0.015 0 0.009

324110 Petroleum refineries 0.040 0.023 0.009 0.032 0 0.004

325180

Other basic inorganic chemical 

manufacturing 0.033 0.004 0.002 0.002 0 0.002

484000 Truck transportation 0.022 7.39 0.533 0.550 0.000 0.013

213112

Support activities for oil and gas 

operations 0.021 0.018 0.013 0.006 0 0.003

331111 Iron and steel mills 0.021 0.176 0.016 0.010 0.000 0.015

482000 Rail transportation 0.016 0.034 0.297 0.014 0 0.007

Exhibit C-7 summarizes supply chain wide use of energy and electricity for producing 

nonmetallic minerals. The nonmetallic mineral mining sector consumes about 70 percent of total 

supply chain primary energy (and almost 80 percent of electricity, as noted above). Other sectors 

consuming high but less significant amounts of energy (in the form of fuels) are power 

generation, truck and pipeline transportation sectors, and petroleum refining.

EXHIBIT C-7: TOP 10 SECTORS USING ENERGY THAT SUPPORT NONMETALLIC MINERAL 

MINING IN 2002 (SORTED BY TOTAL ENERGY USE)

SECTOR

TOTAL

TJ

NON-FOSSIL 

ELECTRICITY 

TJ

Total for all sectors 31.3 4.64

212390 Other nonmetallic mineral mining 18.8 3.88

221100 Power generation and supply 7.542 0.176

211000 Oil and gas extraction 0.899 0.088

484000 Truck transportation 0.726 0.007

331110 Iron and steel mills 0.513 0.062

327992 Ground or treated minerals and earths manufacturing 0.396 0.056

324110 Petroleum refineries 0.305 0.011

3274A0 Lime and gypsum product manufacturing 0.275 0.023

486000 Pipeline transportation 0.241 0.058

482000 Rail transportation 0.208 0.003
C-9

Context: Concrete production and wallboard manufacturing

While the beneficial use studies focus on the substitution of waste products for virgin products, 

and the estimates above identify the avoided energy, cost, and emissions of these substitutions, it 

is important to put into context the effects of the beneficial use. In this section we briefly show 

EIO-LCA results for the broader picture of concrete manufacturing (where fly ash is used in place 

of some cement) and wallboard manufacturing (where FGD gypsum is used in place of virgin 

gypsum). We do this to see how important these raw materials (cement and gypsum) are in the 

supply chain of producing these final products.

Exhibit C-8 shows the top ten sectors that contribute to air emissions, and Exhibit C-9 the top ten 

sectors that consume energy, in the production of concrete. Both outputs were attained by 

running the model using the ready-mix concrete sector and $1 million economic activity; though 

air emissions was run with the 1997 model since 2002 figures are not available, and energy 

consumption was run with the 2002 model. Exhibit C-8 (sorted by SO2 emissions) demonstrates 

that in the manufacture of concrete, the emissions from cement manufacturing account for the 

majority of SO2, NOx, VOC, and PM10 emissions. CO emissions are dominated by truck 

transportation. Similarly Exhibit C-9 shows that cement manufacture represents 40 percent of 

energy use, and almost 50 percent of electricity use. This implies that any reduction in the amount 

of cement needed has a large benefit in the life cycle emissions and energy use of concrete. Thus, 

fly ash substitution even at 20 percent substitution rates is quite beneficial.

EXHIBIT C-8: AIR EMISSIONS OF TOP 10 EMITTING SECTORS THAT SUPPORT CONCRETE 

MANUFACTURING IN THE US IN 1997 (SORTED BY SO2 )

SECTOR

SO2

MT

CO

MT

NOX

MT

VOC

MT

LEAD

MT

PM10

MT

Total for all sectors 6.29 16.9 7.90 5.64 0.001 1.03

327310 Cement manufacturing 3.74 2.43 4.78 3.74 0.000 0.582

221100 Power generation and supply 1.61 0.080 0.728 0.007 0.000 0.034

212310 Stone mining and quarrying 0.570 1.07 0.401 0.202 0 0.118

483000 Water transportation 0.072 0.050 0.382 0.367 0 0.035

325180

Other basic inorganic chemical 

manufacturing 0.055 0.006 0.004 0.003 0 0.003

484000 Truck transportation 0.034 11.3 0.814 0.840 0.000 0.020

482000 Rail transportation 0.025 0.055 0.475 0.022 0 0.011

211000 Oil and gas extraction 0.024 0.041 0.018 0.027 0 0.000

324110 Petroleum refineries 0.021 0.012 0.005 0.017 0 0.002

325998

Other miscellaneous chemical product 

manufacturing 0.013 0.000 0.015 0.003 0 0.001
C-10

EXHIBIT C-9: TOP 10 SECTORS USING ENERGY THAT SUPPORT CONCRETE 

MANUFACTURING IN THE US IN 2002 (SORTED BY TOTAL ENERGY USE)

SECTOR

TOTAL

TJ

NON-FOSSIL 

ELECTRICITY 

TJ

Total for all sectors 23.5 2.08

327310 Cement manufacturing 10.7 0.991

221100 Power generation and supply 3.67 0.086

327320 Ready-mix concrete manufacturing 2.55 0.216

484000 Truck transportation 1.42 0.013

212320 Sand, gravel, clay, and refractory mining 0.977 0.173

325190 Other basic organic chemical manufacturing 0.549 0.03

212310 Stone mining and quarrying 0.392 0.082

324110 Petroleum refineries 0.351 0.013

211000 Oil and gas extraction 0.251 0.025

482000 Rail transportation 0.239 0.004

For gypsum in wallboard manufacturing, a similar method is used, but the sector used to model 

wallboard (Sector #327420: Gypsum Product Manufacturing) is more aggregated than that used 

to model concrete. This industry comprises establishments primarily engaged in manufacturing 

gypsum products such as wallboard, plaster, plasterboard, molding, ornamental moldings, 

statuary, and architectural plaster work. Gypsum product manufacturing establishments may 

mine, quarry, or purchase gypsum. Examples of activities in this sector include:

 Board, gypsum, manufacturing 

 Gypsum building products manufacturing

 Gypsum products (e.g., block, board, plaster, lath, rock, tile) manufacturing

 Joint compounds, gypsum based, manufacturing

 Wallboard, gypsum, manufacturing

Despite the limitations in modeling wallboard as an exclusive product, Exhibits C-10 and C-11 

show the results of the supply chain air emissions and energy use from the gypsum product 

manufacturing sector in EIO-LCA (as a proxy for gypsum wallboard manufacturing). Both 

models are run for 1997, because the 2002 model does not separately distinguish gypsum product 

manufacturing as a sector.
C-11

EXHIBIT C-10: AIR EMISSIONS OF TOP 10 EMITTING SECTORS THAT SUPPORT GYPSUM 

PRODUCT MANUFACTURING IN THE US IN 1997 (SORTED BY SO2 )

SECTOR

SO2

MT

CO

MT

NOX

MT

VOC

MT

LEAD

MT

PM10

MT

221100 Total for all sectors 3.44 18.1 3.94 5.23 0.000 1.02

212310 Power generation and supply 2.22 0.109 1.00 0.010 0.000 0.047

327310 Stone mining and quarrying 0.508 0.951 0.358 0.180 0 0.105

483000 Cement manufacturing 0.284 0.185 0.363 0.284 0.000 0.044

3221A0 Water transportation 0.071 0.049 0.374 0.360 0 0.035

484000 Paper and paperboard mills 0.060 0.406 0.085 0.033 0 0.045

211000 Truck transportation 0.039 12.7 0.918 0.947 0.000 0.022

324110 Oil and gas extraction 0.036 0.061 0.027 0.041 0 0.001

482000 Petroleum refineries 0.025 0.014 0.006 0.020 0 0.003

221200 Rail transportation 0.019 0.041 0.354 0.017 0 0.008

221100 Natural gas distribution 0.019 0.000 0.036 0.129 0 0.001

Exhibit C-10 summarizes the air emissions across the manufacturing supply chain for gypsum 

products (sorted by SO2 emissions). Recall that gypsum was modeled by production of the 

nonmetallic mineral mining sector (and this is the virgin product we would be replacing). 

Nonmetallic mineral mining is not in the top ten emissions sources in any of the tracked 

conventional air emissions for gypsum product manufacturing. Exhibit C-11 shows that the 

nonmetallic mineral mining sector represents about five percent of total energy use of gypsum 

products.

EXHIBIT C-11: TOP 10 SECTORS USING ENERGY THAT SUPPORT GYPSUM PRODUCT 

MANUFACTURING IN THE US IN 1997 (SORTED BY TOTAL ENERGY USE)

SECTOR

TOTAL

TJ

Total for all sectors 24

327420 Gypsum product manufacturing 9.5

221100 Power generation and supply 4.84

3221A0 Paper and paperboard mills 2.16

484000 Truck transportation 1.29

212390 Other nonmetallic mineral mining 1.25

327310 Cement manufacturing 0.698

483000 Water transportation 0.476

327992 Ground or treated minerals and earths manufacturing 0.377

324110 Petroleum refineries 0.28
C-12

Compared to the results for concrete manufacturing sector above, this wallboard example is less 

clear. The wallboard sector was approximated by a highly aggregated sector and is not an 

accurate representation of wallboard manufacturing in our attempt to model gypsum substitution. 

This sector seems to more generally depend on stone sectors for its inputs.
APPENDIX D | DETAILS OF FLY ASH AND FGD GYPSUM LIFE 

CYCLE INVENTORY ANALYSIS METHODOLOGIES
D-1

BEES ANALYSIS OF FLY ASH IN CONCRETE

We calculate the unit impacts of using fly ash as a substitute for finished portland cement in 

concrete as the difference in impacts between concrete made with 100 percent portland cement 

and concrete made with 15 percent fly ash and 85 percent portland cement. Exhibits D-1 and D-2 

show the lifecycle stages modeled by BEES in the production of concrete with and without 

blended cement. These diagrams represent the baseline and beneficial use scenarios evaluated in 

the fly ash analysis.

EXHIBIT D-1: CONCRETE WITHOUT BLENDED CEMENT FLOW-CHART (BASELINE SCENARIO)

EXHIBIT D-2: CONCRETE WITH BLENDED CEMENT FL OW-CHART (BENEFICIAL US E 

SCENARIO)
D-2

It is important to note that in Exhibit D-2, BEES does not actually model the impacts of fly ash 

“production” from coal combustion (i.e. BEES does not allocate electricity production impacts to fly ash).

BEES Life Cycle inventory Data

Exhibits D-3 and D-4 present the complete BEES lifecycle inventory data for a one cubic foot generic 

concrete beam made without and with blended cement (i.e. fly ash). The data fields in the Exhibits are 

defined as follows:

 XPORT DIST: Transport distance of concrete beam to construction site.

 FLOW: The environmental impact being reported.

 UNIT: The unit in which the environmental flow is reported.

 TOTAL: The total impact across all life cycle stages for all three components (i.e., the sum of 

fields COMP1 and COMP2).

 COMP1: The total impact across all life cycle stages for Component 1. Component 1 is the main 

component, which is a 1 cubic yard concrete beam.

 COMP2: The total impact across all life cycle stages for Component 2. Component 2 refers to the 

first installation component associated with the concrete beam, but BEES does not provide a 

specific definition.

 RAW1: Impacts associated with raw materials extraction for Component 1.

 RAW2: Impacts associated with raw materials extraction for Component 2.

 MFG1: Impacts associated with manufacturing of Component 1.

 MFG2: Impacts associated with manufacturing of Component 2.

 XPORT1: Impacts associated with transport of Component 1.

 XPORT2: Impacts associated with transport of Component 2.

 USE1: Impacts associated with use of the total product (all components).

 WASTE1: Impacts associated with disposal of the total product (all components).
D-3

EXHIBIT D-3: BEES LIFE CYCLE INVENTORY DATA FOR GENERIC CONCRETE BEAM WITHOUT BLENDED CEMENT

BEES Data File B1011A - Generic 100% Portland Cement 4KSI - 50 miles

XPORT DIST FLOW UNITS TOTAL COMP1 COMP2 RAW1 RAW2 MFG1 MFG2 XPORT2 XPORT1 USE1 WASTE1

50 Product cubic ft 1 0 0 0 0 0 0 0 0 0 0

50 Main component kg 67.3329 67.3329 0 0 0 0 0 0 0 0 0

50 Total Primary Energy MJ 154 70.58 82.99 64.1 82.6 0 0 6.48 0.39 0 0

50 Non Renewable Energy MJ 115 70.58 44.59 64.1 44.2 0 0 6.48 0.39 0 0

50 Renewable Energy MJ 38.3 0 38.3 0 38.3 0 0 0 0 0 0

50 Water Used (total) l 19.2 10.6 8.62 10.6 8.62 0 0 0 0 0 0

50 (a) Carbon Dioxide (CO2, biomass) g 674 0 674 0 674 0 0 0 0 0 0

50 (a) Carbon Dioxide (CO2, fossil) g 13100 10177 2899.3 9690 2870 0 0 487 29.3 0 0

50 (a) Carbon Monoxide (CO) g 37.9 21.07 16.849 18.6 16.7 0 0 2.47 0.149 0 0

50 (a) Lead (Pb) g 0.0091 0.0001 0.009 0.0001 0.009 0 0 0 0 0 0

50 (a) Mercury (Hg) g 0.0008 0.0005 0.0002 0.0005 0.0002 0 0 0 0 0 0

50 (a) Methane (CH4) g 13.7 9.765 3.917 9.15 3.88 0 0 0.615 0.037 0 0

50 (a) Nitrogen Oxides (NOx as NO2) g 49.9 43.41 6.52 40.1 6.32 0 0 3.31 0.2 0 0

50 (a) Particulates (PM 10) g 1.41 0.5329 0.8815 0.475 0.878 0 0 0.0579 0.0035 0 0

50 (a) Particulates (greater than PM10) g 0 0 0 0 0 0 0 0 0 0 0

50 (a) Particulates (unspecified) g 68.5 65.9415 2.5525 65.9 2.55 0 0 0.0415 0.0025 0 0

50 (a) Sulfur Oxides (SOx as SO2) g 35.5 25.288 10.2414 24.6 10.2 0 0 0.688 0.0414 0 0

50

(w) BOD5 (Biochemical Oxygen 

Demand) g 3.83 0.5316 3.2956 0.439 3.29 0 0 0.0926 0.0056 0 0

50 (w) COD (Chemical Oxygen Demand) g 1.24 0.991 0.2496 0.815 0.239 0 0 0.176 0.0106 0 0

50 (w) Copper (Cu+, Cu++) g 0.0009 0.0008 0.0001 0.0006 0.0001 0 0 0.0001 0 0 0

50 (w) Lead (Pb++, Pb4+) g 0.0025 0.0016 0.001 0.0013 0.001 0 0 0.0003 0 0 0

50 (w) Mercury (Hg+, Hg++) g 0 0 0 0 0 0 0 0 0 0 0

50 (w) Suspended Matter (unspecified) g 10 8.8 1.21 7.47 1.13 0 0 1.33 0.08 0 0

50 (w) Selenium (Se II, Se IV, Se VI) g 0.0001 0.0001 0 0.0001 0 0 0 0 0 0 0

50 Waste (end-of-Life) kg 70.8 0 0 0 0 0 0 0 0 0 70.8
D-4

EXHIBIT D-4: BEES LIFE CYCLE INVENTORY DATA FOR GENERIC CONCRETE BEAM WITH BLENDED CEMENT

BEES Data File B1011B - Generic 15% Fly Ash Cement 4KSI - 50 miles

XPORT DIST FLOW UNITS TOTAL COMP1 COMP2 RAW1 RAW2 MFG1 MFG2 XPORT2 XPORT1 USE1 WASTE1

50 Product cubic ft 1 0 0 0 0 0 0 0 0 0 0

50 Main component kg 67.3445 67.3445 0 0 0 0 0 0 0 0 0

50 Total Primary Energy MJ 147 63.78 82.99 57.3 82.6 0 0 6.48 0.39 0 0

50 Non Renewable Energy MJ 108 63.78 44.59 57.3 44.2 0 0 6.48 0.39 0 0

50 Renewable Energy MJ 38.3 0 38.3 0 38.3 0 0 0 0 0 0

50 Water Used (total) l 18.3 9.63 8.62 9.63 8.62 0 0 0 0 0 0

50 (a) Carbon Dioxide (CO2, biomass) g 674 0 674 0 674 0 0 0 0 0 0

50 (a) Carbon Dioxide (CO2, fossil) g 11800 8927 2899.3 8440 2870 0 0 487 29.3 0 0

50 (a) Carbon Monoxide (CO) g 36.1 19.27 16.849 16.8 16.7 0 0 2.47 0.149 0 0

50 (a) Lead (Pb) g 0.0091 0.0001 0.009 0.0001 0.009 0 0 0 0 0 0

50 (a) Mercury (Hg) g 0.0007 0.0004 0.0002 0.0004 0.0002 0 0 0 0 0 0

50 (a) Methane (CH4) g 12.6 8.705 3.917 8.09 3.88 0 0 0.615 0.037 0 0

50 (a) Nitrogen Oxides (NOx as NO2) g 46.4 39.92 6.52 36.6 6.32 0 0 3.32 0.2 0 0

50 (a) Particulates (PM 10) g 1.4 0.5229 0.8815 0.465 0.878 0 0 0.0579 0.0035 0 0

50 (a) Particulates (greater than PM10) g 0 0 0 0 0 0 0 0 0 0 0

50 (a) Particulates (unspecified) g 65.4 62.8415 2.5525 62.8 2.55 0 0 0.0415 0.0025 0 0

50 (a) Sulfur Oxides (SOx as SO2) g 32.3 22.088 10.2414 21.4 10.2 0 0 0.688 0.0414 0 0

50 (w) BOD5 (Biochemical Oxygen Demand) g 3.8 0.4996 3.2956 0.407 3.29 0 0 0.0926 0.0056 0 0

50 (w) COD (Chemical Oxygen Demand) g 1.18 0.933 0.2496 0.757 0.239 0 0 0.176 0.0106 0 0

50 (w) Copper (Cu+, Cu++) g 0.0009 0.0007 0.0001 0.0006 0.0001 0 0 0.0001 0 0 0

50 (w) Lead (Pb++, Pb4+) g 0.0025 0.0015 0.001 0.0012 0.001 0 0 0.0003 0 0 0

50 (w) Mercury (Hg+, Hg++) g 0 0 0 0 0 0 0 0 0 0 0

50 (w) Suspended Matter (unspecified) g 9.36 8.14 1.21 6.81 1.13 0 0 1.33 0.08 0 0

50 (w) Selenium (Se II, Se IV, Se VI) g 0.0001 0.0001 0 0.0001 0 0 0 0 0 0 0

50 Waste (end-of-Life) kg 70.8 0 0 0 0 0 0 0 0 0 70.8
D-5 

Calculation of Unit Impacts

To illustrate the methodology used to calculate the unit impact values from the BEES life cycle 

inventory data, we present a sample calculation of CO2 reductions resulting from the substitution 

of one ton of fly ash for finished portland cement in concrete (see Exhibit D-5). 

EXHIBIT D-5: EXAMPLE CALCULATION OF IMPACT METRIC FOR CO2 RELATED TO FLY ASH 

SUBSTITUTION IN CONCRETE

CALCULATION

4 KSI CONCRETE 

BEAM NOTE/SOURCES

IMPACTS PER CUBIC YARD CONCRETE

100% portland cement [a]

353,700 grams 

per cubic yard 

of concrete

Values represent impacts related to a 4 KSI 

concrete beam as characterized in BEES data file 

B1011A. BEES Version 4.0 Performance Data. 

15% coal fly ash [b]

318,600 grams 

per cubic yard 

of concrete

Values represent impacts related to building 

products and pavement as characterized in BEES 

data file B1011B. BEES Version 4.0 Performance 

Data. 

Incremental benefit [c]=[a]-[b]

35,100 grams 

per cubic yard 

of concrete

Represents avoided CO2, in grams per cubic yard 

of concrete product substituting 15% coal fly ash 

for portland cement.

IMPACTS PER U.S. SHORT TON FLY ASH

lbs cement/yd3 concrete [d]

470 lbs 

cement/cubic 

yard of concrete

Represents proportion of one cubic yard of 

concrete made up of cementitious material, 

given a mix-design or constituent density 

(Lipiatt, 2002, p. 40).

Percent coal fly ash 

substitution [e] 15% Fifteen percent of cementitious material is replaced with coal fly ash.

lbs/U.S. short ton [f] 2000 lbs/ton Conversion factor for pounds to tons.

tons fly ash/yd3 concrete [g]=[d]*[e]/[f]

0.0352 tons coal 

fly ash/cubic 

yard of concrete

Conversion of quantity of coal fly ash in one 

cubic yard of concrete from pounds to tons.

unit impact [h]=[c]/[g]

995,744 grams 

per ton of coal 

fly ash 

substituted for 

cement

Represent unit impact values for CO2 (in grams), 

based on substitution of one ton of coal fly ash 

for 1 ton portland cement in concrete.

The process outlined in Exhibit D-5 is repeated for each of the environmental metrics evaluated 

in this analysis using the environmental performance data reported in BEES. For each 

environmental metric, this yields an estimate of the benefit of one ton of fly ash replacing 

finished portland cement in concrete.
D-6 

SIMAPRO ANALYSIS OF FGD GYPSUM IN WALLBOARD

We calculate the unit impacts of using FGD gypsum in place of virgin gypsum stucco in 

wallboard as the difference in impacts between wallboard made with 100 percent virgin gypsum 

and wallboard made with 100 percent FGD gypsum. Exhibits D-6 and D-7 show the lifecycle 

stages in the production of wallboard with 100 percent virgin gypsum and 100 percent FGD 

gypsum, respectively. The boxes with dashed lines represent life cycle stages that are unique to 

virgin or FGD gypsum. 

EXHIBIT D-6: VIRGIN GYPSUM WALLBO ARD MANUFACTURE

EXHIBIT D-7: FGD GYPSUM WALLBOARD MANUFACTURE

Gypsum Mining

Stucco Manufacture

Wallboard 

Manufacture

Material Transport

Paper 

Production

Dewatering

Wallboard 

Manufacture

Material Transport

Paper 

Production

Flu Gas 

Desulphurization
D-7 

As shown in Exhibits D-6 and D-7, by replacing virgin gypsum stucco with FGD gypsum, 

gypsum mining and stucco manufacture can be avoided but a dewatering step is added to the 

lifecycle. We model these impacts as one ton of avoided “stucco” manufacture in SimaPro.78

Stucco is the term used in SimaPro to describe the gypsum material used in wallboard. We 

selected the EcoInvent data set because it includes gypsum mining but also includes the 

processing of gypsum for use in wallboard (i.e., burning of gypsum and milling of stucco for use 

in gypsum wallboard). Thus, this dataset includes all the processes that would be avoided if an 

equivalent quantity of FGD gypsum were used in place of stucco in wallboard. The production of 

FGD gypsum through the coal combustion process is not modeled, as discussed in Chapter 4. In 

addition, this analysis assumes that FGD gypsum dewatering occurs via holding ponds and that 

the environmental impacts are negligible.79 This analysis also does not model transport distance; 

we assume FGD gypsum would have the same transport distances to the construction site as 

virgin gypsum.80 Thus avoided gypsum mining and avoided processing of gypsum into stucco, as 

represented by the EcoInvent stucco manufacturing data set, are the only lifecycle stages modeled 

in SimaPro.

Exhibit D-8 presents the assumed life cycle system boundaries for the EcoInvent stucco 

manufacturing data set. The cut-off node for the process flow tree depicted in Exhibit D-8 is set to 

0.5 percent so that the entire tree could be viewed. Thus, this process tree lists the flows 

associated with 99.5 percent of the total life cycle impacts for one ton of stucco manufacture.81

The numbers that appear in the bottom left-hand corner of each box in the tree are partition 

factors used by SimaPro and are not central to this analysis.

The EcoInvent dataset for stucco manufacture is the only stucco dataset available in SimaPro, but 

because it reflects Swiss manufacturing processes and electricity mix, we modified the data for 

stucco manufacture to reflect the average U.S. electricity mix. We made this modification by 

substituting the electricity used to make stucco from gypsum, as well as the electricity used 

further down the production chain in gypsum mining, with the EcoInvent data set for average 

U.S. electricity mix titled “Electricity, medium voltage, at grid/US U”. The EcoInvent data set 

includes the fuel consumption associated with the generation and delivery of an average kilowatthour in the USA using average USA technology in the mid 2000's. While we did not substitute 

the U.S. electricity mix at points further down the stucco production chain, the stucco 

manufacturing and gypsum mining processes account for the majority of electricity use in this 

analysis.

 

78 We use the EcoInvent data set titled “Stucco, at plant/CH U” for this purpose.

79 There may actually be emissions/dusting impacts associated with dewatering in a holding pond, but we have been unable to identify 

quantified estimates of these impacts. Alternatively, dewatering may be accomplished through mechanical processes but we were also 

unable to identify the energy impacts of mechanical dewatering. 

80 We do not model a transport differential between virgin and FGD gypsum to be consistent with the transport assumptions used in the 

BEES fly ash analysis, which helps preserve the comparability of the fly ash and FGD gypsum unit impact values. It is important to note, 

however, that an increasing number of new gypsum wallboard plants are being constructed adjacent to coal-fired power plants, so 

transport distance of FGD gypsum to the wallboard manufacturing facility may, in some cases, be less than the transport distance of 

virgin gypsum.

81 The tree is presented for the “single score” of all life cycle impacts, calculated using the Eco-Indicator 99-H, v2.04 impact assessment 

method.
D-8

EXHIBIT D-8: LIFE CYCLE SYSTEM BOUNDARIES FOR STUCCO MANUFACTURE, 0.5% CUT-OFF
D-9

SimaPro Life Cycle Inventory Data

Exhibit D-9 presents the SimaPro lifecycle inventory data for stucco manufacture for the same metrics 

evaluated in the BEES analysis.

In order to easily compare the results of the FGD gypsum analysis with those of the fly ash analysis, it 

was necessary to convert the environmental metrics reported by SimaPro into the same units that are 

reported by BEES. For most metrics, this required only a simple conversion between different units of 

mass. In the case of energy use, however, SimaPro reports quantities of various fossil fuels consumed 

whereas BEES reports energy consumed in megajoules. To convert the fossil fuel quantities reported by 

SimaPro into equivalent energy content in megajoules, we relied on the Energy Information 

Administration’s Coal, Natural Gas, and Crude Oil Conversion Calculators.82

In addition, SimaPro does not report a single “water use” metric, as is done in BEES, but breaks out fresh 

water use by origin (e.g., lake, river, well, etc.) and application (cooling, turbine, etc). We sum the 

following metrics (converted to liters) to obtain the water use figure in the FGD gypsum analysis: 1) 

Water, cooling, unspecified natural origin/m3, 2) Water, lake, 3) Water, river, 4) Water, turbine use, 

unspecified natural origin, 5) Water, unspecified natural origin/m3, and 6) Water, well, in ground.

 

82 Accessed at http://www.eia.doe.gov/kids/energyfacts/science/energy_calculator.html#coalcalc. 
D-10

EXHIBIT D-9: SIMAPRO LCI DATA FOR ONE TON STUCCO, AT PLANT

SUBSTANCE COMPARTMENT UNIT

STUCCO, AT 

PLANT/CH U (U.S. 

ENERGY MIX)

CONVERTED TO BEES 

UNITS NOTES

Gypsum, in ground Raw kg 1172.49

Total Energy MJ 1,470.76

Non-Renewable Energy MJ 1,454.71

Coal, brown, in ground Raw kg 1.37 MJ 32.07 *converted using the EIA's Energy Calculatora

Coal, hard, unspecified, in ground Raw kg 9.03 MJ 211.86 *converted using the EIA's Energy Calculatora

Gas, mine, off-gas, process, coal 

mining/m3 Raw m3 0.06 MJ 2.34 *converted using the EIA's Energy Calculatora

Gas, natural, in ground Raw m3 24.70 MJ 946.06 *converted using the EIA's Energy Calculatora

Oil, crude, in ground Raw kg 5.85 MJ 262.38 *converted using the EIA's Energy Calculatora

Renewable Energy MJ 16.046

Energy, gross calorific value, in 

biomass Raw MJ 4.39 MJ 4.386

Energy, gross calorific value, in 

biomass, primary forest Raw MJ 1.77E-03 MJ 0.002

Energy, potential (in hydropower 

reservoir), converted Raw MJ 11.05 MJ 11.049

Energy, kinetic (in wind), converted Raw MJ 0.59 MJ 0.589

Energy, solar, converted Raw MJ 0.02 MJ 0.020

Fresh Water Use liter 98,075.97

Water, cooling, unspecified natural 

origin/m3 Raw m3 0.77 liter 765.70
D-11

SUBSTANCE COMPARTMENT UNIT

STUCCO, AT 

PLANT/CH U (U.S. 

ENERGY MIX)

CONVERTED TO BEES 

UNITS NOTES

Water, lake Raw m3 6.66E-04 liter 0.67

Water, river Raw m3 0.06 liter 60.60

Water, turbine use, unspecified 

natural origin Raw m3 97.21 liter 97209.90

Water, unspecified natural 

origin/m3 Raw m3 0.03 liter 28.40

Water, well, in ground Raw m3 0.01 liter 10.70

Carbon dioxide g 86895.82

Carbon dioxide, biogenic Air kg 0.40

Carbon dioxide, fossil Air kg 86.49

Carbon dioxide, land transformation Air kg 1.87E-03

Carbon Monoxide g 41.93

Carbon monoxide, biogenic Air kg 5.86E-05

Carbon monoxide, fossil Air kg 0.04

Lead Air kg 3.42E-05 g 3.42E-02

Mercury Air kg 1.04E-06 g 1.04E-03

Methane g 189.28

Methane, biogenic Air kg 5.63E-04

Methane, fossil Air kg 0.19

Nitrogen oxides Air kg 0.15 g 168.02

Ozone Air kg 1.44E-04 g 0.011

Particulates < PM10 g 520.93

Particulates, < 2.5 um Air kg 0.10
D-12

SUBSTANCE COMPARTMENT UNIT

STUCCO, AT 

PLANT/CH U (U.S. 

ENERGY MIX)

CONVERTED TO BEES 

UNITS NOTES

Particulates, > 2.5 um, and < 10um Air kg 0.47

Particulates, > 10 um Air kg 1.33 g 1,332.96

Sulfur oxides Air kg 0.21 g 211.65

BOD5, Biological Oxygen Demand Water kg 0.03 g 25.47

COD, Chemical Oxygen Demand Water kg 0.03 g 26.61

Copper, ion Water kg 2.25E-06 g 0.002

Lead Water kg 6.37E-06 g 6.37E-03

Mercury Water kg 5.99E-08 g 5.99E-05

Suspended solids, unspecified Water kg 0.01 g 13.92

Selenium Water kg 6.72E-06 g 6.72E-03

Waste, solid Waste kg 0 kg 0 Value not measured in SimaPro record

Notes:

a. Accessed at http://www.eia.doe.gov/kids/energyfacts/science/energy_calculator.html#coalcalc. 
APPENDIX E | POTENTIAL IMPACTS OF ALLOCATION OF 

LCI RESULTS TO CCPs
E-1

While the background literature (ISO framework, etc.) are relatively consistent in their discussion that 

only co-products should share allocation of input and output system flows, this rule leaves out the 

consideration of current and future “waste streams” that have beneficial use potential, or market value that 

suggests that they may be usefully treated as co-products, either because their markets are already 

evolving or because policies under consideration could encourage the evolution of markets.

This observation is inspired by the need to consider the net impacts of CCPs in electricity generation 

when looking at the life cycle impacts associated with beneficial use. While there are beneficial 

substitutions possible of fly ash for cement, FGD gypsum for virgin gypsum, etc., it is possible that if the 

CCPs were in fact treated as co-products instead of as wastes, that there would be non-negligible inputs 

and outputs from coal-fired electricity generation that merited attention when estimating net impacts. In 

this section we consider some hypothetical macro-level scenarios for coal-fired power generation, as well 

as macro-level flows of several key CCPs. These scenarios are then applied in an assessment of 

implications of allocating the environmental effects of power generation to both the energy product and 

the CCPs.

Traditional LCA allocation rules suggest that product and co-product allocation by economic value, mass, 

energy, etc., are all legitimate methods – there is no single approach to allocating that is correct. For the 

first illustration, we show an approximate economic value based allocation and the resulting effects for 

CCPs, followed by a prospective mass-based method.

ECONOMIC ALLOCATION

The electricity industry has about $300 billion per year in gross revenues. Roughly 50 percent of 

generation is coal-fired at the national level. Even though the costs and revenues per kilowatt hour vary 

across generation types, and the total value includes generation, transmission, and distribution, for 

simplicity we assume that there is 50 percent, or $150 billion of revenues from coal-fired power 

generation. If we were to adjust for the variations in price per kilowatt hour, this value would likely be 

closer to $100 billion from coal-fired generation, as coal represents a lower-cost form of energy 

production. 

From ACAA (2008) and USGS (2010), we consider the upper bound economic value of various CCPs, 

using both the high end of estimated market value for the CCPs, as well as the high end estimate of CCPs 

produced, and not the quantity used. Table E-1 summarizes these results for the top three CCPs in terms 

of market value and production.

TABLE E-1: OPTIMISTIC SCENARIO OF CCP MARKET VALUES (ACAA 2008, USGS 2006)

CCP

2009 MARKET VALUE

(PER TON)

CCP PRODUCTION 

(MILLION TONS)

TOTAL MARKET VALUE 

(ABSOLUTE UPPER BOUND)

Fly Ash $49.53 72.5 $3.59 billion

FGD Gypsum $8.81 17.8 $0.16 billion

Bottom Ash $8.81 18.4 $0.16 billion

Total -- ------- 108.6 $3.91 billion

Summing the total value of these three products yields $3.5 billion. Even this upper-bound estimate is 

only 2 to 3 percent of the value of the electricity produced, if considered as shares of the total economic 
E-2

value of the product (electricity) and co-products (CCPs) created by coal-fired power plants. Of course, 

the values in Table E-1 are highly optimistic, and ACAA estimates that fly ash market value ranges from 

$20-45/ton in 2003, and bottom ash from $4-8 per ton in 2003. Thus, the actual economic value 

allocation would likely be significantly smaller – probably less than one percent. As these were the 

“best case” allocation results, it seems that allocating by economic value would lead to negligible results. 

MASS-BASED ALLOCATION

The example above is straightforward in demonstrating that economic allocation is possible and feasible, 

but leads to negligible results. Another alternative in LCA is to use mass-based allocation of impacts 

from products and co-products of a process. In the case of CCPs from coal-fired power generation, the 

product is electricity, which has no mass, which means it is impossible to purely allocate by mass. 

However, as an illustration, we consider the allocation results assuming that the electricity generated is 

completely tied to the combustion of coal, which has known mass. This is a simplifying but fair 

assumption since there are few other significantly large mass based inputs into coal combustion processes 

(process water is generally reused and returned).

If the mass-based allocation were considered as such, and thinking again at the macro-level of all coalfired power plants, there are about one billion tons of coal used as input. As summarized in Table E-1, 

there are about 109 million tons of the top three market value CCPs, and about 136 million tons total 

CCPs, generated per year by the power plants. Thus, CCPs represent about 14 percent of the mass, with 

individual mass allocations of about 7 percent for fly ash, two percent for gypsum, and two percent for

bottom ash. Thus, in this hypothetical example, the mass-based allocations would, in fact be much larger 

than the economic value allocations, but still generally a small percentage of total "mass" production. 

Further, considering the other major mass flows in the plant, these numbers may, in fact, be smaller. 

Another caveat is that not all CCPs produced are beneficially used. Thus, the mass allocations may 

converge back to the shares estimated above for economic allocation.

SAMPLE CALCULATIONS

Given the substitution of CCPs for virgin materials production, and the potential effects of allocating 

some of the environmental flows of electric power generation to CCPs, we investigated what the 

comparative net effects would be if the estimated low range of mass or dollar based allocations for CCPs 

(of coal-fired generation) were compared to the avoided emissions from coal fly ash and FGD gypsum 

beneficial use. For simplicity we consider CO2 and SO2 emissions only.

In 2008, coal-fired generation in the electric power sector resulted in 1.9 billion metric tons of CO2

emissions.83 From our overview of potential allocation values for CCPs from coal-fired generation, we 

estimated that the percent allocations would be, in sum, on the order of about one percent. If we allocated 

one percent of CO2 emissions from coal-fired electricity generation to the CCPs, then about 21 million 

short tons of CO2 would be allocated to their "production." In comparing this one percent allocated value 

to the CO2 benefits estimated separately by BEES and Simapro, we see that the avoided portland cement 

and virgin gypsum use accounts for about 11.5 million short tons of CO2 emission benefits. Similarly, for 

SO2, coal-fired generation leads to most electricity generation emissions, which total about 10 million 

metric tons per year.84 One percent of this number is about 100,000 metric tons SO2, though this includes 

emissions from all Conventional Power Plants and Combined-Heat-and-Power Plants and therefore 

 

83 EIA, 2010, “Table 12.2 Carbon Dioxide Emissions From Energy Consumption: Total (All Sectors) and Electric Power Sector, 1949-2009,” accessed 

Nov. 20, 2010 at http://www.eia.doe.gov/aer/txt/ptb1202.html.

84 EIA, 2010, “Table 12.7b Emissions From Energy Consumption for Electricity Generation and Useful Thermal Output: Electric Power Sector, 1989-

2008. Accessed Nov. 20, 2010 at http://www.eia.doe.gov/aer/txt/ptb1207b.html.
E-3

overstates the impact of coal combustion. However, Exhibit 5-3 in Chapter 5 of this report estimates 

avoided cement and gypsum manufacturing SO2 emissions to be 26,000 short tons (23.9 million metric 

tons or 23.9 billion grams), suggesting that SO2 emissions reductions associated with beneficial reuse are 

small when compared with the allocated emissions impacts associated with energy production from coal.

As indicated in our high-end CO2 and SO2 examples presented above, allocated emissions from primary 

production (i.e., coal combustion) may occasionally be greater than the documented benefits of beneficial 

use for some metrics. However, it is important to note that this allocation procedure reflects an 

accounting procedure designed only to more accurately apportion emission impacts across co-products. It 

can be correctly interpreted as an indication that the beneficial use of CCPs may not be an efficient 

method for reducing overall emissions of CO2 and SO2 to the environment. However, the actual CO2 and 

SO2 emissions avoided from the beneficial use of coal fly ash and FGD gypsum remain positive, as 

reported. 

While this analysis has focused only on CO2 and SO2 (there are similar emissions from coal-fired 

generation of NOx, PM10, etc.), it demonstrates the type of framework that could be in place to help 

assess the efficiency of beneficial use. It is likely that within such a framework that life cycle inventory 

data would be greater for one effect and lower for others, rather than a vector dominance situation. Thus, 

appropriate weighting methods should be identified to help balance the overall perceived benefit of such 

substitutions. EPA's TRACI model and the BEES model itself could serve to normalize and weight 

preferences of environmental flows against each other to lead to singular assessments of results.

SUMMARY

LCA allows for the allocation of input and output flows across the life cycle to the various products and 

co-products of processes and systems. However CCPs are generally considered waste, and not coproducts of power generation. Even if they were considered co-products, the allocated input and output 

flows from coal-fired generation would associate only very small flows to the CCPs relative to the 

electricity produced. For this reason, and because our assessment here represents a high-end screening 

analysis, we do not include either an economic or mass-based allocation of coal combustion impacts to fly 

ash or FGD gypsum in our presentation of extrapolated findings in chapter 5.