Document ID: EPA-HQ-RCRA-2008-0329-0239
Agency: epa
Document Type: Supporting & Related Material
Title: 
Posted Date: 2009-01-02T05:00Z

Materials Characterization Paper

In Support of the

Advanced Notice of Proposed Rulemaking –

Identification of Nonhazardous Materials That Are Solid Waste

Scrap Tires

December 17, 2008

=======================================================

Definition of Scrap Tires  

Scrap tires are used tires that can no longer be utilized as tires. 

Annual Quantities of Scrap Tires Generated and Used

Sectors that generate scrap tires:  Scrap tires are generated from the
replacement of tires on passenger and commercial vehicles.  

The majority of scrap tires, 88 percent, come from passenger vehicles
and light duty trucks.  The remaining 11 percent comes from larger
vehicles such as heavy duty trucks and buses (RMA 2006, p. 10).  

Many scrap tires are sent to processors where they are shredded and then
sent to end users such as: plants using tire-derived fuel; civil
engineering projects (e.g., construction sites for landfills, septic
tank leach fields, or roads); and crumb rubber plants where they may be
recycled into other products (Virginia Department of Environmental
Quality 2008).  Other tires are used whole, either in civil engineering
or similar projects or as a fuel.

Quantities of Scrap Tires Generated:  Consumers and industry in the
United States generated 299.6 million scrap tires in 2005; this
represents approximately 4.9 million tons of tires, assuming an average
of 33 pounds per tire (RMA 2006, p.11).  Of these tires, less than 15
percent were landfilled.  These landfilled tires are “wasted”, with
their resource value being lost to society.  Exhibit 1 provides a brief
overview of the generation and use of scrap tires in 2005.  Exhibit 2
provides more detailed information on the uses of scrap tires from 1990
through 2005.

Exhibit 1: Overview of Generation and Use for 2005

Commodity	Annual Quantity Generated	Annual Quantity Used as Fuel	Annual
Quantity Land Disposed	Annual Quantity Diverted to Other Uses1	Total
Quantity Stockpiled as

 of 2005

Scrap Tires2	299.6 million tires

4.4 million tons	155.1 million tires

2.1 million tons

177 facilities	42.42 million tires

0.6 million tons	104.1 million tires

1.5 million tons	188.0 million tires

2.9 million tons

Sources:

Unless otherwise noted, data are from the Rubber Manufacturers
Association, Scrap Tire Markets in the United States, November 2006, p.
88.

Notes:

1.    The quantity diverted to other uses includes 6.9 million exported
tires weighing approximately 0.1 million tons.

2.    Of the 4.4 million tons of tires generated in 2005, the Rubber
Manufacturers Association (RMA) has accounted for how 4.2 million tons
were managed. RMA was unable to determine how the remaining 0.2 million
tons were managed.

Exhibit 2:  Summary of Scrap Tire Uses from 1990 to 2005

Millions of Tires Used

Scrap Tire Use	1990	1992	1994	1996	1998	2001	2003	2005

Tires Used for Tire Derived Fuel	24.5	57.0	101.0	115.0	114.0	115.0	129.7
155.1

Cement Kilns	6.0	7.0	37.0	34.0	38.0	53.0	53.0	58.0

Pulp/paper Mills	13.0	14.0	27.0	26.0	20.0	19.0	26.0	39.0

Industrial Boilers	0.0	6.0	10.0	16.0	15.0	11.0	17.0	21.0

Utility Boilers	1.0	15.0	12.0	23.0	25.0	18.0	23.7	27.0

Non-Fuel Uses	0.0	11.0	37.5	49.5	63.5	103.0	103.6	104.0

Civil Engineering	N/A	5.0	9.0	10.0	20.0	40.0	56.4	49.2

Ground Rubber	0.0	5.0	1.5	7.5	7.0	21.0	18.2	30.1

Export	0.0 	0.0	12.5	15.0	15.0	15.0	9	6.9

Cut/Punched/Stamped	N/A	N/A	8.0	8.0	8.0	8.0	6.5	6.1

Miscellaneous/Agriculture	N/A	1.0	3.5	4.0	5.5	7.0	3.0	3.0

Electric Arc Furnaces	N/A	N/A	N/A	N/A	N/A	N/A	0.5	1.3

Rubber Modified Asphalt	N/A	N/A	3.0	5.0	8.0	12.0	10.0	7.4

Scrap Tires in Stockpiles	1000.0	1,000.0	800.0	500.0	400.0	300.0	275.0
188.0

Sources:

Unless otherwise noted, data is from the Rubber Manufacturers
Association, Scrap Tire Markets in the United States, November 2006, p.
86.

(3) Trends in Generation:

Scrap tire generation increased by 25 percent from 1990 to 2005, while
the amount reused or recycled increased from 11 percent in 1990 to 87
percent in 2005.  This reflects a major accomplishment in effective
materials management.

During this same period, the number of tires in stockpiles declined by
more than 80 percent, from 1 billion to 188 million (RMA 2006, p.86).

The use of tires for fuel has increased from 24.5 million tires in 1990
to 155.1 million tires in 2005.  The Rubber Manufacturers Association
(RMA) suggests that the use of tires as a fuel source will likely
continue and may increase as the cost of conventional fossil fuels
increases (RMA 2006, p.20).

States have contributed to the increased use of scrap tires as a fuel
and for other purposes by regulating scrap tires and by working with the
public and private sectors to improve the management of scrap tires to
minimize landfilling, stockpiling, and illegal dumping (EPA 2007). 
Exhibit 3 demonstrates that stockpiles have been depleted despite
increased generation, while Exhibit 4 illustrates the increasing rate of
reuse/recycling of scrap tires.

Exhibit 3:  Changes in Scrap Tire Generation and Stockpile Depletion

Exhibit 4:  Changes in Scrap Tire Generation and Reuse/Recycling

Uses of Scrap Tires

Combustion Uses of Scrap Tires:  

A major use of scrap tires is as fuel, either in whole form or as
tire-derived fuel (TDF).  Whole tires are frequently used as fuel in
cement kilns, where their steel provides an additional benefit, as kiln
operations require iron. Otherwise, use of whole tires is limited by
whether they fit into combustion units (EPA 2008b).  TDF is defined by
ASTM as scrap tires that have been shredded and processed into rubber
chips according to product standards.  The use of TDF in combustion
units is typically limited to blends of 10 – 30 percent of total
energy input due to the high rates of heat release and the low moisture
content of TDF.  Thus, TDF is often used as a supplementary fuel in
combustors to complement other fuel sources such as coal and biomass
(ASTM 2006, p.4). 

Cement manufacturers account for 40 percent of users of tires as fuel in
the United States.  Electric utilities were the second largest users (33
percent) and paper manufacturers were the third largest users (20
percent).  These three industries account for more than 90 percent of
users of tires as fuel in the United States (RMA 2006, pp. 89-90)

As of 2005, there were 121 facilities using tire-derived fuel in the
U.S. (RMA 2006, pp. 89-90).  Exhibit 5 presents the 3-digit NAICS codes
for these facilities.  Appendix 1 includes basic identifying information
for each facility in the U.S. known to be utilizing TDF.

The use of scrap tires as fuel accounts for nearly 60 percent of the
beneficial use of scrap tires, as indicated in Exhibit 6. 

As shown in Exhibit 7, the use of tires as fuel has increased
significantly since 1990.  RMA indicates that the increased use of tires
as fuel is likely due to increased energy prices for conventional fossil
fuels and improvements in tire processing (RMA 2006, p.17).

Exhibit 5:  NAICS Codes for Facilities Using Tire-Derived Fuel

NAICS	NAICS Title	Count

327	Nonmetallic Mineral Product Manufacturing	49

221	Utilities	40

322	Paper Manufacturing	24

331	Primary Metal Manufacturing	3

611	Educational Services	2

311	Food Manufacturing	1

928	National Security and International Affairs	1

562	Waste Management and Remediation Services	1

Source:

U.S. Census Bureau 2007

Non-Combustion Scrap Tire Uses:  Although energy recovery is the most
common use of scrap tires, there are many non-fuel uses for scrap tires
including the following:

Agriculture/Miscellaneous (i.e., erosion control) (RMA 2006, p.51)

Civil Engineering (i.e., construction of landfills and roads) (RMA 2006,
pp. 33,36)

Cut/Punched/Stamped into other products (e.g., floor mats) (RMA 2006,
p.43)

Electric Arc Furnaces (i.e., these units combust tires to utilize energy
value and to incorporate carbon and steel into new steel products) (RMA
2006, p. 47)

Ground Rubber (e.g, synthetic sports field turf) (RMA 2006, p. 39)

Rubber Modified Asphalt (RMA 2006, p.44)

Exhibit 6:  Use of Scrap Tires in 2005

 (Source:  RMA 2006, p.86)

Similar to the increased use of scrap tires as a fuel source, the
beneficial use of scrap tires in non-combustion applications has
increased significantly between 1990 and 2001. Since 2001, however, the
amount of scrap tires used for non-combustion applications has been
fairly constant, whereas the amount used as fuel has continued to
increase.  This trend reflects the high fuel value of tires.  The
increased acceptance of tires as a legitimate fuel led to success in
reduction of tire piles.  With the increase in fuel prices since 2001,
beneficial use of tires as fuel has become a more attractive management
option than other beneficial use applications.

Exhibit 7:  Trends in the use of Scrap Tires from 1990 – 2005

 (RMA 2006, pp 17-18)

Quantities of Scrap Tires Landfilled:  The number of tires landfilled
has slowly declined as the use of TDF and other applications for tires
has increased.  This trend reflects an important environmental
accomplishment.  Despite efforts to minimize the number of tires sent to
landfills, tires are still landfilled because of the high cost of
hauling tires to a processing facility in some areas, or if they are in
too poor of condition to be suitable for beneficial use applications. 
This reflects a significant waste of resources.  In general, the
placement of whole tires in above-ground landfills is discouraged due to
their large size, flammability, and potential to harbor mosquitoes.  As
an alternative, scrap tires may be placed in an underground monofill
(RMA 2006, p.53).  While EPA considers monofill disposal preferable to
traditional above-ground tire piles, these are also a clear waste of
valuable resources (EPA 2007).

Quantities of Scrap Tires Stockpiled/Stored: Stockpiles of tires have
been steadily decreasing as a result of state efforts to eliminate
“tire piles.”  States are typically responsible for regulating scrap
tires, and each state, with the exceptions of Alaska and Delaware, has
developed laws and requirements to address scrap tire concerns.  While
some states focus mostly on the management of scrap tires as they are
generated, others have also developed programs to address existing tire
stockpiles (EPA 2007).  The majority of current stockpiles are located
in seven states: Alabama, Colorado, Connecticut, Michigan, New York,
Pennsylvania, and Texas (RMA 2006, p.7).  As indicated in Exhibit 3, the
number of tires in stockpiles has fallen by more than 80 percent since
1990.  Most states, like EPA, encourage the use of tires as fuel.  Some
states have formally determined, under state law, that combustion of
tires is not related to waste management, but is actually a beneficial
use of resources.

Management and Combustion Processes for Tire-Derived Fuel

Types of Units Combusting Tires as Fuel:  Tires are combusted as fuel in
a variety of applications, including in boilers and kilns (RMA 2006,
p.86).  They can be used to supplement and/or replace a wide range of
fuels including coal, coke, fuel oil, natural gas, and wood.  Although
many combustion units were not designed to burn tires, many are able to
use tires as a supplement to conventional fuels (ASTM 2006, pp. 1 and
4).  

(2) Supply/Processing Chain for Tires Used as Fuel: While scrap tires
are generated from many different sources, they are generally
consolidated at key collection points (e.g., tire retailers, automotive
repair shops, and fleets) through well-established channels before being
shipped to processing facilities and end users.  Exhibit 8 summarizes
the processing chain for scrap tires used as TDF.  Scrap tires are also
recovered from historical tire piles.

Exhibit 8:  Typical Process for Recovering Tires for Tire-Derived Fuel

 

(Texas Commission on Environmental Quality 2008)

1. In some cases, combustion devices accept whole tires, which can
provide environmental advantages over chipped tires (e.g., energy
savings from avoided chipping and improvement of combustion
characteristics).

(3) Processing Scrap Tires for Fuel Applications:  

	Scrap tires are often processed through two physical processing steps:
chipping/ shredding and metal removal.  Shredded tires used as fuel
consist of chipped tires ranging in size from 1 to 4 inches; the amount
of metal in this material varies depending on how much the tires have
been processed.  This processing step is beneficial for many combustion
units because it minimizes the metals content of the tires and improves
heating efficiency.  The price of TDF increases with the removal of
metals (ASTM 2006, p.5).  However, some units such as cement kilns do
not require the removal of wire because their processes are hot enough
to oxidize the wire.  Also, the metals provide a positive value in the
process as a substitute for raw materials, and considerable energy is
saved by not chipping tires.  Furthermore, some argue that the
combustion characteristics of tires (and the emissions produced) are
improved when combusted whole in certain combustion devices (e.g.,
cement kilns).  

Because the specifications for TDF are somewhat user specific, the ASTM
has not issued recommended specifications for TDF or the processing of
scrap tires for use as TDF. 

While newly generated scrap tires can typically be processed for TDF
applications, many tires in tire piles are in such poor condition that
they cannot be processed and used as TDF.  The only notable potential
use of these tires is in cement kilns, and otherwise, the only viable
management option is landfill or monofill disposal (RMA 2006, pp. 22,
53).  

(4) Recognition of Value in Using this Alternate Fuel – by Regional,
State, and Academic Parties:

The  Resource Conservation Challenge (RCC) Scrap Tire Workgroup has two
goals related to scrap tires: (1) to manage  85 percent of scrap tires
through reuse, recycling, and energy  recovery  and  (2) to  reduce the
number of stockpiled tires by 55 percent from  2001 to 2008.  To help
meet these goals, the RCC workgroup has developed subcommittees to
target different applications in order to make progress, one of which is
the  Tire-Derived Fuel Subcommittee, which is striving to support the 
expanded and appropriate use of scrap tires as a supplemental energy
resource in properly permitted industrial facilities (RMA 2006, p.76).

  

(5) State Status of Scrap Tire Used as Fuel:  

According to state responses to a 2006 survey by the Association of
State and Territorial Solid Waste Management Officials (ASTSWMO), the
following states have approved the use of scrap tires as fuel on at
least one occasion:  Maryland, Pennsylvania, Kentucky, Maine, and North
Dakota.  This use does not appear to have pre-approved status, however,
suggesting that a case-by-case approval process for designation of
beneficial use is in place in these states (ASTSWMO 2007, p.B-38-39). 
In addition, the following states have given pre-approved beneficial use
determinations to the use of scrap tires as fuel:  Indiana, Iowa, North
Carolina, and Virginia.

Scrap Tire and TDF Composition and Impacts

Composition of Tires Used as Fuel:

Tires have a high energy content ranging from 12,000 – 16,000 Btus per
pound.  This is higher than many conventional fossil fuels (e.g., coal).
 Tires that have been processed to remove metal will have higher heating
values per pound than tires that have not been processed to minimize
metals.  However, cement kilns report that the savings are greater
overall when energy is not expended to shred tires.  Also, the metal in
tires is an important raw material in cement manufacturing.

The Btu Values of tires and a number of other fuels are as follows:

Tires: 12,000 – 16,000 Btu/pound (North Carolina Division of Pollution
Prevention and Environmental Assistance (NCDPPEA))

Coal: 11,000 - 13,000 Btu/pound (NCDPPEA and EIA 2005, Table A5)

Wood 5,000 Btu/pound (NCDPPEA)

Gas 21,000 – 24,000 Btu/pound (ASTM 2006, p.5)

Oil 17,000 – 19,000 Btu/pound (ASTM 2006, p.5)

Exhibit 9 summarizes the metals content of tire-derived fuel and two
fuels that it may displace: fuel oil and coal.

Exhibit 9: Metals Content of TDF, Fuel Oil, and Coal

Metals Concentrations (Parts Per Million by Weight)

	TDF	Fuel Oil	Coal

Barium	Non-detect	0.3	200

Cadmium	6	0.5	0.5

Chromium	97	0.5	20

Lead	65	-	40

Manganese	<100	-	70

Zinc	15,200	-	100

Sources:

TDF estimates and the zinc estimate for coal are from EPA 1998, p. 1-5

Fuel oil and coal (excluding zinc) are from Gray 2004, p. 11

Impact Information

Cost Savings of Beneficial Use Applications: The net cost savings
associated with the beneficial use of scrap tires (i.e., the cost
savings realized less the costs associated with beneficial use) are a
function of (1) avoided disposal costs, (2) fuel (or other input)
savings associated with the beneficial use of this material, and (3)
processing (e.g., shredding) and other costs associated with beneficial
use.  Exhibit 10 summarizes readily available information on these
variables.  Based on this information, it is not possible to generate a
single estimate of the net cost savings or benefits associated with the
beneficial use of scrap tires.  As suggested by the exhibit, avoided
disposal costs depend on the location of disposal.  In addition,
information is not readily available on the costs of processing tires
for beneficial use applications.

Exhibit 10:  Summary Economic Savings and Costs of Scrap Tire Beneficial
Use

Savings

Avoided Disposal Costs 

Tip fees associated with landfill disposal vary by location and depend
on the size of the tire.  Example tip fees reported by local waste
management authorities in California, Pennsylvania, and Virginia are as
follows:

California: $68 per ton (California Integrated Waste Management Board)

Centre County, Pennsylvania: $66 per ton (Centre County Solid Waste
Authority, 2003)

Page County, Virginia: $155 per ton (Page County, 2008)

Fuel or Material Cost Savings 

The fuel and material costs savings associated with beneficial use
depend on the value of the fuel or input for which scrap tires serve as
a substitute.  The average cost of various fuels for which scrap tires
are a substitute are as follows (2007 prices unless otherwise noted):1

Natural Gas (Industrial): $7.35 / MMBtu (EIA 2008a, Table 20)

No. 2 Distillate (Industrial): $16.80 / MMBtu (EIA 2008b, Table 36)

Residual Fuel Oil Average:  $9.19 / MMBtu (EIA 2008b, Table 38)

Coal – Average Delivered Price in 2006: $2.23 / MMBtu (EIA 2007, Table
ES1)

Costs

Processing and Other Costs of Beneficial Use

Information on the costs of scrap tire beneficial use applications is
not readily available.

Notes:

To express these values as dollars per MMBtu, the following thermal
conversion factors were used: 1,031 Btu per 1,000 cubic foot of natural
gas, 138,690 Btu per gallon of Number 2 distillate, 149,690 Btu per
gallon of residual fuel oil, and 22,473,000 Btu per short ton of coal
(EIA 2005, Tables A1, A4, and A5).

Criteria Pollutants and Hazardous Air Pollutants: Although numerous
studies have been conducted on the criteria pollutant and hazardous air
pollutant (HAP) emissions associated with tire-derived fuel, most of
these studies examine fuels that are a combination of scrap tires and
conventional fuels.  Therefore, these studies do not isolate the
criteria pollutant or HAP emissions associated with scrap tires alone.  

Although existing studies do not include sufficient data to isolate the
emissions associated with scrap tires alone, it is possible to reach a
few general conclusions based on the results of these studies.  For
example, emissions test data compiled by EPA in 1997 suggest that
substituting scrap tires for coal in electric utility boilers may lead
to reductions in NOx and particulate matter emissions but show no clear
pattern for SOx emissions (EPA 1997, p. 35).  The same study also
examined the emissions impacts associated with tire combustion at
several other types of facilities (e.g., pulp and paper mills, cement
kilns, and industrial boilers) that use a variety of different fuels. 
In addition, a 2004 paper by Gray includes information on the emissions
impact of TDF at six sample facilities.  Based on this paper and the
1997 EPA study, Exhibit 11 indicates whether the use of tires as a fuel
at each facility type may lead to a reduction or an increase in
emissions.  The available studies on emissions related to tires as fuel
examine only a limited number of emissions sources, and it is unclear
whether these sources are representative of the combustion units that
may use tires.  Note that at well-controlled facilities, emissions will
not change significantly when tires are used.  We further note that
variation in emissions could be attributable to factors other than the
use of tires itself (such as variations in air pollution control device
efficiency).

Exhibit 11: Emissions Impact of Using Tires as a Substitute for
Conventional Fuels, by pollutant and combustor type

	NOx	PM	SO2	Zinc

Utility boilers	Reduction	Reduction	Data inconclusive	Data inconclusive

Industrial boilers	Reduction	Reduction	Data inconclusive	Increase

Pulp & paper mills	Reduction or similar	Increase	Increase	Increase

Cement kilns	Data inconclusive	Reduction	Reduction	Data inconclusive

Sources:  

The information presented in this exhibit is based on emissions data in
EPA 1997 and Gray 2004.

Notes: 

1.    “Reduction” indicates that emissions test data suggest that
the use of TDF as a fuel will reduce emissions.  “Increase”
indicates that emissions may increase, and “similar” indicates that
emissions are unlikely to change.  “Data inconclusive” indicates
that the available emissions data show no clear pattern with respect to
the emission impact of using TDF as a substitute for conventional fuel.

Upstream Emissions Impacts: Use of tires as a replacement for fossil
fuels may eliminate the environmental impacts associated with extraction
and processing of the traditional fuels.  Exhibit 12 lists the
quantities of cradle-to-gate emissions for these fuels based on typical
processes in the United States in the late 1990s.  The generation of
scrap tires generally creates minimal emissions.  Of course, there are
impacts associated with the shredding of scrap tires into TDF, and these
are not accounted for in Exhibit 12.  

Other Impacts: In addition to the impacts outlined above, the beneficial
use of scrap tires limits, and in some cases prevents, the growth of
scrap tire stockpiles.  This could result in improvements to human
health and the environment because such stockpiles provide habitat for
disease vectors (such as mosquitoes and rodents), and because they can
catch fire, creating large amounts of toxic smoke and hazardous liquids
that can contaminate air, water and soils.

Exhibit 12:  Emissions from Extraction and Processing of Traditional
Fuels

Pollutant	Coal	Distillate Fuel Oil	Residual Fuel Oil	Wood	Natural Gas

	---------------------------- Lb./MMBtu ----------------------

Criteria Pollutants

PM2.5	-	-	-	-	-

PM10	-	-	-	-	-

PM, unspecified	0.246	0.012	0.012	6.67x10-4	0.004

NOx	0.022	0.061	0.062	0.08	0.117

VOCs	0.008	0.361	0.365	-	0.515

SOx	0.022	0.186	0.187	0.003	1.913

CO	0.017	0.046	0.046	0.022	0.223

Pb	2.60x10-7	1.01x10-6	1.00x10-6	-	2.72x10-7

Hg	8.17x10-8	1.87x10-7	1.87x10-7	-	7.18x10-8

Source:

Franklin Associates 1998.

Note:

“-” signifies data not available; may equal zero.

The emission information presented in this table is derived from Life
Cycle Inventory (LCI) data, as compiled by Franklin Associates.   LCI
data identifies and quantifies resource inputs, energy requirements, and
releases to the air, water, and land for each step in the manufacture of
a product or process, from the extraction of the raw materials to
ultimate disposal. The LCI can be used to identify those system
components or life cycle steps that are the main contributors to
environmental burdens such as energy use, solid waste, and atmospheric
and waterborne emissions.  Uncertainty in an LCI is due to the
cumulative effects of input uncertainties and data variability.  

There are several life cycle inventory databases available in the U.S.
and Europe.  For this paper, we applied the most readily available LCI
database that was most consistent with the materials and uses examined.
These LCI data rely on system boundaries as defined by Franklin
Associates, as described in the documentation for this database,
available at:   HYPERLINK
"http://www.pre.nl/download/manuals/DatabaseManualFranklinUS98.pdf" 
http://www.pre.nl/download/manuals/DatabaseManualFranklinUS98.pdf .  



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2006 Kiln List_Received 8_25_2008”, internal EPA document provided by
EPA on August 25, 2008.

Virginia Department of Environmental Quality.  2008,  “Regional
Collection and Processing Projects”, accessed August 21, 2008 at:  
HYPERLINK "http://www.deq.virginia.gov/wastetires/progsummary2.html" 
http://www.deq.virginia.gov/wastetires/progsummary2.html .

Appendix 1: Summary of Facilities Using Tires as Fuel

TDF User	City	State	Type of Facility	NAICS

6 unspecified sites	Across state	FL	Waste-to-Energy	221

AES Hawaii	Oahu	HI	Industrial Boiler	221

Akron Thermal, LLP 	Akron	OH	Utility Boiler	221

Allegany Power	Parkersburg	WV	Utility Boiler	221

Allen Steam Plant	Memphis	TN	Utility Boiler	221

Alliant Energy	Cassville	WI	Utility Boiler	221

Alliant Energy Edgewater Generating Station	Sheboygan	WI	Utility Boiler
221

Ameren/UE, Inc.	Portage Des Sioux	MO	Utility Boiler	221

American Resource Recovery Corp.	Monroe	MI	Industrial Boiler	221

Aquila, Inc.	St. Joseph	MO	Utility Boiler	221

Aquila/Sibley Generating Station	Kansas City	MO	Utility Boiler	221

Black River Electric	Fort Drum	NY	Utility Boiler	221

Cogentrix	Roxboro	NC	Industrial Boiler	221

Cogentrix	Southport	NC	Industrial Boiler	221

Cogentrix	Lumberton	NC	Industrial Boiler	221

Cogentrix	Richmond	VA	Industrial Boiler	221

East Kentucky Power	Maysville	KY	Utility Boiler	221

Empire District Electric Co. Asbury Power Plant	Joplin	MO	Utility Boiler
221

Exeter Energy	Sterling	CT	Dedicated Tire-to-energy Facility	221

Grayling Generating Station	Grayling	MI	Industrial Boiler	221

Hillman Power	Hillman	MI	Utility Boiler	221

Illinois Power	Baldwin	IL	Utility Boiler	221

Mt. Poso Cogeneration	Bakersfield	CA	Utility Boiler	221

Owensboro Municipal Utilities	Owensboro	KY	Utility Boiler	221

Port Stockton District Energy Facility 	Stockton	CA	Industrial Boiler
221

Ridge Generating Station	Auburndale	FL	Utility Boiler	221

Stockton Co-Generation	Stockton	CA	Industrial Boiler	221

Tire Energy Corp (TEC)	Martinsville	VA	Industrial Boiler	221

Tondu Energy	Filer City	MI	Utility Boiler	221

Trigen Biopower	Hodges	SC	Industrial Boiler	221

Viking Energy	McBain	MI	Utility Boiler	221

Viking Energy	Lincoln	MI	Utility Boiler	221

WPS Empire State	Niagra Falls	NY	Industrial Boiler	221

Wyandotte Power	Wyandotte	MI	Utility Boiler	221

Xcel Energy Bayfront Plant	Ashland	WI	Utility Boiler	221

Archer Daniels Midland 	Decatur	IL	Industrial Boiler	311

Boise	Deridder	LA	Pulp and Paper Mill	322

Bowater	Catawba	SC	Pulp and Paper Mill	322

Bowater	Calhoun	TN	Pulp and Paper Mill	322

Cascade	Boise	ID	Pulp and Paper Mill	322

Domtar, Inc.	Ashdown	AR	Pulp and Paper Mill	322

Georgia Pacific	Crossett	AR	Pulp and Paper Mill	322

Georgia Pacific	Brunswick	GA	Pulp and Paper Mill	322

Georgia Pacific	Woodland	ME	Pulp and Paper Mill	322

Inland-Rome	Rome	GA	Pulp and Paper Mill	322

International Paper Corporation	Courtland	AL	Pulp and Paper Mill	322

International Paper Corporation	Pine Bluff	AR	Pulp and Paper Mill	322

International Paper Corporation	Mansfield	LA	Pulp and Paper Mill	322

International Paper Corporation	Bastrop	LA	Pulp and Paper Mill	322

International Paper Corporation	Bucksport	ME	Pulp and Paper Mill	322

International Paper Corporation	Eastover	SC	Pulp and Paper Mill	322

International Paper Corporation	Georgetown	SC	Pulp and Paper Mill	322

Interstate Paper	Riceboro	GA	Pulp and Paper Mill	322

NewPage Corporation	Wickliffe	KY	Pulp and Paper Mill	322

NewPage Corporation	Rumford	ME	Pulp and Paper Mill	322

NewPage Corporation	Chillicothe	OH	Pulp and Paper Mill	322

Smurfit-Stone Container Enterprise	Stevenson	AL	Pulp and Paper Mill	322

Sonoco Products Company	Hartsville	SC	Pulp and Paper Mill	322

SP Newsprint Co.	Dublin	GA	Pulp and Paper Mill	322

Thilmany Papers	De Pere	WI	Pulp and Paper Mill	322

Allentown Cement	Blandon	PA	Cement Kiln	327

Ash Grove Cement Co.	Foreman	AR	Cement Kiln	327

Ash Grove Cement Co.	Inkom	ID	Cement Kiln	327

Ash Grove Cement Co.	Chanute	KS	Cement Kiln	327

Ash Grove Cement Co.	Durkee	OR	Cement Kiln	327

Ash Grove Cement Co.	Midlothian	TX	Cement Kiln	327

Ash Grove Cement Co.	Leamington	UT	Cement Kiln	327

Ash Grove Cement Co.	Seattle	WA	Cement Kiln	327

Buzzi Unicem USA	Oglesby	IL	Cement Kiln	327

Buzzi Unicem USA	Cape Giradeau	MO	Cement Kiln	327

California Portland Cement	Ontario	CA	Cement Kiln	327

Capital Cement	San Antonio	TX	Cement Kiln	327

CEMEX	Demopolis	AL	Cement Kiln	327

CEMEX	Victorville	CA	Cement Kiln	327

CEMEX	Brooksville	FL	Cement Kiln	327

CEMEX	Clinchfield	GA	Cement Kiln	327

CEMEX	Knoxville	TN	Cement Kiln	327

CEMEX	New Braunfels	TX	Cement Kiln	327

CEMEX/Downtown Cement	Odessa	TX	Cement Kiln	327

Chemical Lime Company	Grantsville	UT	Lime Kiln	327

Essroc Cement Corp.	Joppa	MD	Cement Kiln	327

Essroc Cement Corp.	not specified	MD	Lime Kiln	327

Essroc Cement Corp.	Pryor	OK	Cement Kiln	327

Essroc Cement Corp.	Meadville	PA	Cement Kiln	327

Florida Rock Industries	Gainesville	FL	Cement Kiln	327

Holcim Inc.	Theodore	AL	Cement Kiln	327

Holcim Inc.	Florence	CO	Cement Kiln	327

Holcim Inc.	Mason City	IA	Cement Kiln	327

Holcim Inc.	Dundee	MI	Cement Kiln	327

Holcim Inc.	Clarksville	MO	Cement Kiln	327

Holcim Inc.	Ada	OK	Cement Kiln	327

Holcim Inc.	Midlothian	TX	Cement Kiln	327

Holcim Inc.	Morgan	UT	Cement Kiln	327

Lafarge North America	Calera	AL	Cement Kiln	327

Lafarge North America	Grand Chain	IL	Cement Kiln	327

Lafarge North America	Tulsa	OK	Cement Kiln	327

Lafarge North America	Whitehall	PA	Cement Kiln	327

Lafarge North America	Harlyeville	SC	Cement Kiln	327

Lehigh Cement Company	Leeds	AL	Cement Kiln	327

Lehigh Southwest	Redding	CA	Cement Kiln	327

Lone Star Cement	Mary Neal	TX	Cement Kiln	327

Mitsubishi Cement Corp.	Lucerne Valley	CA	Cement Kiln	327

Monarch Cement Company	Humboldt	KS	Cement Kiln	327

National Cement	Ragland	AL	Cement Kiln	327

National Cement Co. of California	Lebec	CA	Cement Kiln	327

Rinker Materials Corporation	Brooksville	FL	Cement Kiln	327

St. Lawrence Cement Co.	Hagerstown	MD	Cement Kiln	327

Texas Industries Cement	New Braunfels	TX	Cement Kiln	327

Texas Lehigh Cement	Buda	TX	Cement Kiln	327

Gerdau Ameristeel	Jackson	TN	Electric Arc Furnace	331

Nucor Steel	Jackson	MS	Electric Arc Furnace	331

Nucor Steel	Auburn 	NY	Electric Arc Furnace	331

Southeastern Public Service Authority	Portsmouth	VA	Industrial Boiler
562

University of Missouri-Columbia	Columbia	MO	Industrial Boiler	611

University of Wisconsin Charter Street Plant	Madison	WI	Industrial
Boiler	611

Fort Detrick	Fredrick	MD	Industrial Boiler	928

(RMA 2006, pp. 89-90 and U.S. Census Bureau 2007)

 The Scrap Tire Workgroup contributes to the overall goals of Resource
Conservation Challenge (RCC), a multi faceted initiative implemented by
USEPA with three overarching goals: 1. to prevent pollution and promote
recycling and reuse of materials; 2.  to reduce the use of toxic
chemicals; and 3. to conserve energy and materials. The Scrap Tire
Workgroup of the RCC works on various issues related to scrap tire
management and markets. The workgroup consists of over 50
representatives from various state environmental agencies, industry,
trade groups, EPA and academia with expertise in scrap tire management,
market development, and application technologies.

 This list of facilities was comprised from the Rubber Manufacturers
Association list of users of tires as fuel.  EPA has published a more
recent list that includes 48 cement kilns but we used the RMA list as it
is consistent with the combustion data used throughout this paper (EPA
2008c).

Scrap Tires

 PAGE   

 PAGE   2 

Sent to TDF facility for combustion.

Tires are chipped/shredded.1

Tires are transported to processing facilities.

Tires that are no longer usable are collected at retailers, fleets, etc.
until they are ready for transport.

Scrap tires are removed from passenger vehicles and trucks.