### Materials Characterization Paper In Support of the Proposed Rulemaking: Identification of Nonhazardous Secondary Materials That Are Solid Waste – Scrap Tires

April 6, 2010



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1. Definition of Scrap Tires

Scrap tires are used tires that can no longer be utili zed as tires.

2. Annual Quantities of Scrap Tires Generated and Used

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

• The majority of scrap tires, 85 percent, come from passenger vehicles and light duty trucks. The remaining 15 percent come s from larger vehicles such as heavy duty trucks and buses (RMA 2009).

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

(2) Quantities of Scrap Tires Generated: Consumers and industr y in the United States generated 4.6 million tons of tires in 2007, or an estimated 303.2 million scrap tires (RMA 2009). Of these tires, roughly 13 pe rcent 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 2 005 and 2007 (except for the total annual quantity generated, 2007 figures are available only in terms of weight). Exhibit 2 provides more detailed information on the uses of scrap tires from 1990 through 2007.Scrap Tires



### Exhibit 1: Overview of Generation and Use for 2005 and 2007

Commodity Annual Quantity Generated Annual Quantity Used as Fuel Annual Quantity Land Disposed Annual Quantity Diverted to Other Uses 1 Total Quantity Stockpiled as of 2005/2007 Scrap Tires

(2005) 2 299.6 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 Scrap Tires

(2007) 3 4.6 million tons 303.2 million tires 2.5 million tons 0.6 million tons 1.5 million tons 128.4 million tires

Sources: Data for 2005 are from RMA 2006, and data for 2007 are from RMA 2009. Notes: 1. The quantity diverted to other uses includes roughly 0.1 million tons of exported tires in both 2005 and 2007.. 2. Of the 4.4 million tons of tires generated in 2005, the Rubber Manufacturers Association (RMA) ha s accounted for how 4.2 million tons were managed. RMA was unable to determine how the remaining 0.2 million tons were managed. 3. In its 2009 report, RMA states that, henceforth, it will include only weight-based figures in its published market data. This reflects the evolution of data reporting within the industry. Historically, RMA presented scrap tire data in units, consistent with the first major report on scrap tire management complete d by EPA. However, some governments and tire industry organizations present data in terms of weight, and the EPA Resource Conservation Challenge Tire Workgroup has recommended use of weight-based data. RMA states that this full conversion is necessary fo r consistency and precision of data, though it will make comparisons to previous years cha llenging. However, RMA still reports the quantity stockpiled in numbers of tires, because stockpile estimates continue to be given in units.



### Exhibit 2: Summary of Scr ap Tire Uses from 1990 to 2007
Millions of Tires Used Scrap Tire Use 1990 1992 1994 1996 1998 2001 2003 2005 2007 1 Tires Used as fuel (whole and shredded) 24.5 57.0 101.0 115.0 114.0 115.0 129.7 155.1 179.6 Cement Kilns 6.0 7.0 37.0 34.0 38.0 53.0 53.0 58.0 48.4 Pulp/paper Mills 13.0 14.0 27.0 26.0 20.0 19.0 26.0 39.0 77.1 Industrial Boilers 0.0 6.0 10.0 16.0 15.0 11.0 17.0 21.0 14.5 Utility Boilers 1.0 15.0 12.0 23.0 25.0 18.0 23.7 27.0 24.9
Non-Fuel Uses 0.0 11.0 37.5 49.5 63.5 103.0 103.6 104.0 94.9 Civil Engineering N/A 5.0 9.0 10.0 20.0 40.0 56.4 49.2 43.1

Ground Rubber 0.0 5.0 1.5 7.5 7.0 21.0 18.2 30.1 43.0 Export 0.0 0.0 12.5 15.0 15.0 15.0 9 6.9 6.3 Cut/Punched/Stamped N/A N/A 8.0 8.0 8.0 8.0 6.5 6.1 0.1 Miscellaneous/Agriculture N/A 1.0 3.5 4.0 5.5 7.0 3.0 3.0 0.5 Electric Arc Furnaces N/A N/ A N/A N/A N/A N/A 0.5 1.3 1.9 Rubber Modified Asphalt 2 N/A N/A 3.0 5.0 8.0 12.0 10.0 7.4

- Scrap Tires in Stockpiles 1000.0 1,000.0 800.0 500.0 400.0 300.0 275.0 188.0 128.4 Sources: Data for 1990 through 2005 are from RMA 2006, and data for 2007 are from RMA 2009. Notes:

1. RMA 2009 includes figures only in weight for 2005 and 2007, as well as percent change between 2005 and 2007. To

approximate 2007 figures in terms of the quantity of tires, in order to demonstrate how various uses have changed over time, we applied the percent change in weight between 2005 and 2007 to the 2005 quantity figures. However, the 2007 stockpile figure was given in quantity of tires. 2. Rubber modified asphalt was not sepa rated out as a category in RMA 2009. 3. The tire derived fuel (TDF) total in cludes dedicated tires to energy.

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### (3) Trends in Generation:

• Scrap tire generation increased by 36 percent from 1990 to 2007, while the amount reused or recycled increased from 11 percent in 1990 to 89 percent in 2007 (RMA 2009). This reflects a major accomplishment in effective materials management.

• During this same period, the number of tires in stockpiles dec lined by more than 87 percent, from 1 billion to 128 million (RMA 2009).

• The use of tires for fuel has increase d from 24.5 million tires in 1990 to roughly 179.6 million tires in 2007 (RMA 2009). 1 

### 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 conve ntional fossil fuels increases (RMA 2006).

• The combustor survey database devel oped by EPA for the 2009 proposal of the Commercial and Industrial Solid Waste Incinerator (CISWI) standards and the Industrial Boilers Maximum Achievable Control Technology (MACT) standards indicates that the sources surveyed fo r these rules annually combust 599,000 tons of scrap tires 2 

### (EPA 2009).

• States have contributed to the increased us e 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.

1 We approximated this 2007 figure of numbers of tires used as fuel by applying the percent change in weight of tires used for fuel between 2005 and 2007 (RMA 2009) to the 2005 quantity figure.

2 Although we report scrap tire data from the com bustion database as a tonnage, the database includes material quantities expressed in terms of heating values (B tu). To express this information as a tonnage, we assumed that scrap tires have a heating value of 14,000 Btu per pound, which is the midpoint of the 12,000 to 16,000 Btu/lb range referenced below from the North Carolina Division of Pollution Prevention and Environmental Assistance.

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### Exhibit 3: Changes in Scrap Tire Generation and Stockpile Depletion

Scrap Tire Generation Compared to the Number of Scrap Tires in Stockpiles

0 100 200 300 400 500 600 700 800 900 1000 1100

1990 1992 1994 1996 1998 2001 2003 2005 2007

Year# of Tires (Millions)

Scrap Tire Generation
Scrap Tires in Stockpiles

Data from RMA 2009



### Exhibit 4: Changes in Scrap Ti re Generation and Reuse/Recycling

Scrap Tire Generation Compared to the Number of Scrap Tires Recycled or Recovered

0 50 100 150 200 250 300 350

1990 1992 1994 1996 1998 2001 2003 2005 2007

Year# of Tires (Millions) Scrap Tire Generation
Scrap Tires Recycled or Recovered

Data from RMA 2009. We approximated th e number of scrap tires recycled or recovered in 2007 by applying the reported percentage recycled or recovered in 2007 to the reported generation of scrap tires for 2007.



### 3. Uses of Scrap Tires

(1) Combustion Uses of Scrap Tires: A major use of scrap tires is as fuel, eith er in whole form or as tire-derived fuel (TDF). The southeast is currently the stronge st market for use of scrap tires as fuel (Blumenthal 2009a). Whole tires are frequently used as fuel in cement kilns, and the reinforcing steel with in tires provides an additional benefit (Gray 2009). Otherwise, use of whole tires is limited by whether they are compatible with the combustion and

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### handling characteristics of individual combustion units (EPA 2008c, Gray 2009). TDF is defined by ASTM as sc rap 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 less than 30 pe rcent 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).

• Pulp and paper manufacturers accounted for 43 percent of the fuel use of TDF, by weight, in the United States in 2007. Ot her users include ce ment manufacturers (27 percent of fuel use), elec tric utilities (14 percent of fuel use), industrial boilers (8 percent of fuel use), and dedicated tire -to-energy facilities (8 percent of fuel use). These figures represent a shif t since 2005, when cement manufacturers accounted for 37 percent of use and pulp and paper manufacturers accounted for 25 percent. From 2005 to 2007, use of TDF by pulp and paper manufacturers increased by 98 percent (RMA 2009).

• Currently, a total of 66 ceme nt kilns (at 43 cement produc tion facilities ) burn tires as fuel in the United States. Only ten of these kilns burn shredded tires; the remaining 56 kilns burn whole tires (Blumenthal 2009a).

• Data on the precise breakdown between shre dded tires and whole scrap tires in the scrap tire fuel market are not readily available. However, based on data from RMA (2009) and Blumenthal (2009a), EPA es timates that shredded tires make up 69 percent of the market and whol e tires make up 31 percent.

 As indicated in Exhibit 2, RMA (2009) divides the scrap tire fuel market across different user industries. The RMA (2009) document also suggests that cement kilns and dedicated tire-to-energy plants are the main consumers of whole tires. To estimate the segmentation of the market, EPA therefore assu med that all other facilities burn shredded tires. In addition, based on RMA (2009), EPA assumed that dedicated tire-to-energy facilities burn whole tires exclusively and that cement kilns burn both whole tires and shredded tires. To distribute cement kiln tire use between whole tires and shredded tires, EPA relied upon data provided by Blumenthal (2009a) on the number of cement kilns that burn whole tires and the number that burn shredded tires. EPA assumed that the breakdown between whole tires and shredded tires among cement kilns is proportional to the percentage of kilns that burn whole tires and the percentage that burn shredded tires.



### • As of the end of 2007, there were 123 fac ilities permitted to use tire-derived fuel in the U.S. (RMA 2009). Exhibit 5 pres ents the 3-digit NAICS codes for these facilities. Appendix 1 includes basic iden tifying information for each facility in the U.S. known to be utilizing TDF.

• The use of scrap tires as fu el accounts for roughly 53 per cent of the beneficial use of scrap tires, as i ndicated 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).

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### Exhibit 5: NAICS Codes for Faci lities Using Tire-Derived Fuel

NAICS NAICS Title Count 1

327 Nonmetallic Mineral Product Manufacturing 2 44 221 Utilities 22 322 Paper Manufacturing 32 562 Waste Management and Remediation Services 8 Various Other Industrial Boilers 17 Source: RMA 2009 U.S. Census Bureau 2007 Note: 1. The values presented here are based on information in Chapter 3 of RMA 2009. Appendix C of RMA 2009, however, includes slightly different values. 2. This sector includes cement kilns, a major user of TDF discussed throughout this paper.



### (2) Non-Combustion Scrap Tire Uses: Although energy recovery is the most common use of scrap tires, there are many non-fuel us es for scrap tires in cluding the following:

• Agriculture/Miscellaneous (i.e., erosion control)

• Civil Engineering (i.e., construction of landfills and roads)

• Cut/Punched/Stamped into other products ( e.g ., floor mats)

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

• Ground Rubber ( e.g ., synthetic sports field turf)

• Rubber Modified Asphalt (RMA 2006)

Exhibit 6: Use of Scrap Tires in 2007

Source: RMA 2009.

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### • 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, and currently, a high percentage of truck tires are diverted into ground rubber applications (Blument hal 2009a). Since 2001, however, the amount of scrap tires used for non-com bustion 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.

• Cooperation from state agencies is crucia l to the growth and development of noncombustion applications of scrap tires. For example, despite Rubber Modified Asphalt’s potential to absorb large amount s of scrap tires (one highway lane absorbs approximately 1,000 scrap tires), reluctance on the part of state transportation agencies due to cost a nd performance concerns has hindered its growth as a market (Frye 2009; RMA 2009; Gray 2009).

Exhibit 7: Trends in the use of Scrap Tires from 1990 – 2007

0 50 100 150 200 250 300

1990 1992 1994 1996 1998 2001 2003 2005 2007

Year# of Tires (Millions) Rubber Modified Asphalt

Electric Arc Furnaces
Miscellaneous/Agriculture
Cut/Punched/Stamped

Export

Ground Rubber
Civil Engineering

Tires Used for Tire Derived Fuel

Data from RMA 2009. We approximated 2007 figures in terms of the quantity of tires, in order to demonstrate how various uses have changed over time, by applying the percent change in weight between 2005 and 2007 to the 2005 quantity figures



### (3) 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 accomplis hment. 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 (i.e., landfilling is often the least costly management option), or if they are in too poor of condition to be suitable for

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### beneficial use applications. This reflects a significant waste of resources. In general, the placement of whole tires in above-gr ound landfills is discouraged due to their large size, flammability, and potential to har bor mosquitoes. As an alternative, scrap tires may be placed in an underground m onofill (RMA 2006). While EPA considers monofill disposal preferable to traditional above-ground tire piles, these are also a clear waste of valuable resources (EPA 2007).

(4) Quantities of Scrap Ti res Stockpiled/Stored: Stockpiles of tires ha ve been steadily decreasing as a result of state efforts to e liminate “tire piles.” States are typically responsible for regulating scrap tires, and each state, with the exceptions of Alaska and Delaware, has developed laws and requi rements to address scrap tire concerns. While some states focus mostly on the ma nagement of scrap tires as they are generated, others have also developed pr ograms to address existing tire stockpiles (EPA 2007). The majority of current stockpi les are located in se ven states: Alabama, Arizona, Colorado, Massachusetts, Michig an, New York, and Texas (RMA 2009). As indicated in Exhibit 2, the number of tires in stockpiles has fallen by over 87 percent since 1990. Most states , like EPA, encourag e the use of tires as fuel. Some states have formally determined, under st ate law, that combus tion of tires is not related to waste management, but is act ually a beneficial use of resources.

4. Management and Combustion Pro cesses for Tire-Derived Fuel

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

(2) Supply/Processing Chain for Tires Used as Fuel : While scrap tires are generated from many different sources, they are gene rally consolidated at key collection points ( e.g ., tire retailers, automotive repair shop s, and fleets) through well-established channels before being shipped to processi ng facilities and end users. Exhibit 8 summarizes the processing chain for scrap tire s used as TDF. An additional source for scrap tires is historical tire piles. Furthermore, some tire processors send TDF to end-users indirectly, through br okerage firms (Sorcher 2009).

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### Exhibit 8: Typical Process for Reco vering Tires for Tire-Derived Fuel

Source: Texas Commission on Environmental Quality 2008 

### Scrap tires are removed from pa ssenger vehicles and trucks.

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

Tires are transported to processing facilities.

Tires are chipped/shredded. 1



### Sent to TDF facility for combustion.

Note : 1 . In some cases, combustion devices accept whole tires , which can provide envir onmental advantages over chipped tires ( e.g ., energy savings from avoided chipping).



### (3) Processing Scrap Tires for Fuel Applications: Scrap tires are often pro cessed 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 am ount 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. However, shredding tires to the smaller particle size require d to remove metals increases processing costs (Gray 2009). The price of TDF therefore increases with sm aller particle sizes conducive to metal removal (ASTM 2006, Gray 2009). 3 

### Tire processors can sort their material by metal content and charge higher prices for mate rial with 90 percent of the metal wire removed (Gray 2004).

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 ra w materials, and considerable energy is saved by not chipping tires. Furtherm ore, 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). Currently, there are at least

3 The extraction of metals from tires can also caus e deterioration of shredding equipment, which adds further to processing costs (Grantham 2009).

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### five states whose scrap tire programs dive rt whole tires for use as fuel in cement kilns: Alabama, California, Oklahoma, Pe nnsylvania, and Texas (Blumenthal 2009a).

In addition to chipping/shredding a nd metal removal, some TDF producers are experimenting with pyrolysis, but it has not become commercially successful due to high capital costs associated with processing equipment and the relatively low value of the outputs produced, especially the solid char product (CIWMB 1992, Gray 2009). 4



### Because the specifications for TDF are some what 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 typi cally be processed for TDF applications, many tires in tire piles are in such poor condition that they cannot be processed and used as TDF. When tires from large stoc kpiles are processed, it is usually onsite at the stockpile itself; to avoid the degrad ation of processors’ primary equipment, stockpile tires are not shipped to proce ssors’ main facilities (Blumenthal 2009b). Besides landfill or monofill disposal, the only other notable potential uses of these tires are in cement kilns and civil engi neering applications (Gray 2009, RMA 2006).

(4) Recognition of Value in Using this Al ternate Fuel – by Regional, State, and Academic Parties: The Resource Conservation Challe nge (RCC) Scrap Tire Workgroup 5 

### has two goals related to scrap tires: (1) to manage 85 per cent of scrap tires thr ough reuse, recycling, and energy recovery and (2) to reduce the number of stockpiled tires by 55 percent from 2001 to 2008. To help meet thes e goals, the RCC workgroup has developed subcommittees to target diffe rent 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 tire s as a supplemental energy resource in properly permitted industrial facilities (RMA 2006).

(5) State Status of Scrap Tire Used as Fuel: According to state respons es to a 2006 survey by the Association of State and Territorial Solid Waste Management Offi cials (ASTSWMO), the following states have approved the use of scrap tires as fuel on at least one occasion: Maryland, Pennsylvania, Kentucky, Maine, and North Da kota. This use does not appear to have pre-approved status, however, suggesting that a case-by-ca se approval process for

4 To a lesser extent, there has been some experimentat ion with the use of cryogenics to shatter scrap tires into TDF chips, but an established industry for the use of cryogenics in the production of TDF has not yet developed (CIWMB 1992; Sorcher 2009).
5 The Scrap Tire Workgroup contributes to the overa ll 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 issu es related to scrap tire management and markets. The workgroup consists of over 50 representatives from vari ous state environmental agenci es, industry, trade groups, EPA and academia with expertise in scrap tire management, market development, and application technologies.

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### designation of beneficial use is in pl ace in these states (ASTSWMO 2007). According to ASTSWMO, the following stat es have given pre-a pproved beneficial use determinations to the use of scrap tire s as fuel: Indiana, Iowa, North Carolina, and Virginia. In addition, RM A data indicate that TDF has been approved for use in facilities in 34 states (RMA 2009).

5. Scrap Tire and TDF Co mposition and Impacts

(1) Composition of Tires Used as Fuel: Tires have a high energy content rang ing 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 steel reinforcing wire will have higher h eating values per pound than tires that have not b een processed to minimize wire metals. However, cement kilns report that the savings are greater overa ll when energy is not expended to shred tires. Also, the steel in tire s is an important raw material in cement manufacturing.

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

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

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

• Wood 5,000 Btu/pound (NCDPPEA)

• Gas 21,000 – 24,000 Btu/pound (ASTM 2006)

• Oil 17,000 – 19,000 Btu/pound (ASTM 2006)

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 Mercury - <0.1 0.1 Zinc 15,200 - 100 Sources: Fuel oil and coal estimates (exc luding zinc) are from EPA 1998. TDF estimates and zinc estimate for coal are from Gray 2004.



### (2) 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 re alized less the costs associated with beneficial use) are a f unction of (1) avoided disposal costs, (2) fuel (or other input) savings associated w ith the beneficial use of this material, and (3) processing ( e.g ., shredding) and other costs associated with beneficial

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### use. 6 

### Exhibit 10 summarizes readily availa ble 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 di sposal costs depend on the location of disposal. In addition, cost savings can vary dependi ng on the whether tires are shredded or whole. For example, a limite d number of state programs pay cement kilns to receive whole tires at their faci lities; one source estimates that kilns are paid between five and fifteen cents pe r tire (Blumenthal 2009), while another source estimates that kilns are paid up to twenty-five cents pe r tire (Gray 2009). However, some kilns take whole tires for free, and all kilns pay for shredded tires (Blumenthal 2009a). Information is not readily available on the costs of processing tires for beneficial use applications.

Exhibit 10: Summary Economic Savings an d 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 averag e 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:

1. To express these values as dollars per MMBtu, the following thermal conversion factors were used: 1,031 Btu per 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).

6 With respect to the costs asso ciated with beneficial use, cement kiln operators are generally required to enact performance testing and air permit modifications prior to using scrap tires and other alternative fuels. In addition, kilns may be required to install continuous emissions monitoring systems if they chose to burn scrap tires (EPA 2008a).

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### • End-users running different combustion un its will be willing to pay different prices based on the kind of fuel that is being replaced by TDF. For example,cement kilns often substitute TDF for low-grade coals, which are a relatively lowcost fuel. This translates into a lowe r willingness to pay. End-users substituting TDF for high-grade coal, oil or natural gas are more likely to pay higher prices for TDF. However, the relationship between metal content, operational efficiency, and willingness to pay of an end-user also depends on the specific combustion unit and cannot be generalized acr oss an industry (Sorcher 2009).

• Greenhouse Gas Emissions: Data compiled by the Greenhouse Gas Protocol, suggests that the greenhouse gas emissions rate associat ed with the combustion of scrap tires is approximat ely 0.081 metric tons of carbon dioxide equivalents (MTCO2E) per million Btu (MMBtu) of scrap tires combusted (GHG Protocol, 2005). By comparison, based on emissi ons and energy data compiled by EPA, the GHG emissions rates for coal, natural ga s, distillate oil, and residual oil are approximately 0.094 MTCO2E per MMBtu, 0.053 MTCO2E per MMBtu, 0.073 MTCO2E per MMBtu, and 0.079, MTCO2E per MMBtu, respectively (EPA 2008b). These estimates do not include upstream emissions impacts ( e.g ., from the extraction and transport of virgin materials), which are presented below in Exhibit 12.

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

Although existing studies do not include suffi cient 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 scra p tires for coal in electric utility boilers may lead to reductions in NO x 

### and particulate matter emissions but show no clear pattern for SO x 

### emissions (EPA 1997). The same study also examined the emissions impacts associated with ti re 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 arerepresentative of the combustion units that may use tires. Note that at wellcontrolled facilities, emissi ons will not change signifi cantly when tires are used. 7

7 EPA notes that its 1997 study was a laboratory te st program (not full-scale) that assessed controlled burning of TDF in a Rotary Kiln Incinerator Simulator (RKIS). While the study concluded that, with the exception

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### We further note that variati on in emissions could be attr ibutable to factors other than the use of tires itself (such as va riations in air pollu tion control device efficiency).

Exhibit 11: Emissions Impact of Using Tires as a Substitute for Conventional Fuels, by Pollutant and Combustor Type

NO x PM SO 2 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 inco nclusive” indicates that the availa ble 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 associ ated with extracti on 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 outline d above, the beneficial use of scrap tires limits, and in some cases preven ts, the growth of scra p tire stockpiles. This could result in improvements to hum an health and the environment because such stockpiles provide habitat for dis ease 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.

of zinc emissions, potential emissions from TDF are not expected to be very much different than from otherconventional fossil fuels, it noted “as long as combustion occurs in a well-designed, well-operated, and wellmaintained combustion device." The study also clarified “Very little data exist for devices that are not welldesigned and use scrap tires for fuel. These sources include fireplaces, wood st oves, small kilns, small incinerators, or any device with poor combustion characteristics. Air emissions from these types of devices are likely between that of open burning and a combustor. There is serious concern that emissions would be more like those of an open tire fire than a well-designed combustor; however, emissions testing would have to be conducted to confirm this.”

14Scrap Tires



### Exhibit 12: Emissions from Extraction and Processing of Traditional Fuels

Coal Distillate Fuel Oil Residual Fuel Oil Wood Natural Gas Pollutant 

### ---------------------------- 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
Greenhouse Gases
CO 2 3.9 19 19.1 - 15.3

CH 4 0.451 0.029 0.029 - 0.369

N 2 O 1.63x10 -5 2.01x10 -5 2.07x10 -5

- 1.17x10 -5

MTCO 2 E/MMBtu 0.006 0.009 0.009 - 0.01 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 st ep 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 cycl e steps that are the ma in 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 ava ilable 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: http://www.pre.nl/download/manuals /DatabaseManualFranklinUS98.pdf

.

15Scrap Tires



### References

ASTM International. 2006, “Standard Prac tice for Use of Scrap Tire-Derived Fuel”.

Blumenthal, Michael. 2009a, Personal Communication with Lyn Luben, U.S. EPA, July 9, 2009.

Blumenthal, Michael. 2009b, Personal Communication with Jason Price, Industrial Economics, July 21, 2009.

Association of State and Territorial Solid Waste Management Officials (ASTSWMO), 2006 Beneficial Use Study Report , November 2007.

California Integrated Waste Management Board, “Solid Waste Facility Tipping Fees: 1998 to 2000 Summaries of Special Waste Tipping Fee Surveys” , accessed August 28, 2008 at: http://www.ciwmb.ca.gov/la ndfills/TipFees/SumSW.htm

California Integrated Waste Management Board, “Tires as a Fuel Supplement: Feasibility Study”, January 1992, accessed June 18, 2009 at: http://www.ciwmb.ca.gov/Publi cations/default.asp?pubid=90

Centre County Solid Waste Auth ority. 2003, “Tipping Fees”, accessed August 27, 2008 at: http://www.centrecountyrecycles.com/Recycle/RefuseTippingFees/RefuseTippingFees.html

. Franklin Associates. 1998, “Franklin US LCI 98 Library”.

Frye, Neal. 2009, Entech, Incorporated. Personal Communication. July 3, 2009.

GHG Protocol (the Greenhouse Gas Protocol Initiative). 2005, “CO2 Emissions from the Production of Cement (CSI)”, accessed on August 21, 2008 at: http://www.ghgprotocol.org/cal culation-tools/cement-sector

. Gray, Terry. 2004, “T ired Derived Fuel: Environmental Characteristics and Performance”.

Gray, Terry. 2009, TAG Resource Recovery. Personal Communication. August 24, 2009.

Grantham, Dewey. 2009, Liberty Tire Recycling, Inc. Personal Communication. May 26, 2009.

North Carolina Division of Pollution Prevention and Environmental Assistance, “Tire Derived Fuel”, accessed August 20, 2008 at: http://www.p2pays.org/ref/11/10504/html/usa/tdf.htm

. Page County, “Landfill, Compactor, & Recycli ng Sites”, accessed August 27, 2008 at http://pagecounty.virginia.gov/index.php?option=content&task=view&id=163

. Rubber Manufacturers Association, “Scrap Tire Characteristics”, accessed August 21, 2008 at: http://www.rma.org/scrap_ tires/scrap_tire_markets/scrap_tire_characteristics/

Rubber Manufacturers Association. 2006, “Scrap Tire Markets in th e United States”. 2005 Edition.

Rubber Manufacturers Association. 2009, “Scrap Tire Market s in the United States”. 9 th Biennial Report.

Sorcher, Michael. 2009, M.A. Associates, In c. Personal Communication. May 27, 2009.

Texas Commission on Environmenta l Quality. 2008, “Scrap Tires” , accessed August 21, 2008 at: http://www.tceq.state.tx.us/compliance/tires/index.html#gen

.
United States Census Bureau, “2007 NAICS Co des and Titles”, accessed August 21, 2008 at: http://www.census.gov/naics/2007/NAICOD07.HTM U.S

.

16Scrap Tires

United States Energy Informati on Administration (EIA). 2007, Annual Coal Report 2006

. United States Energy Informati on Administration (EIA). 2005, Annual Energy Review 2004.

United States Energy Information Administration (EIA). July 2008a, “Natural Gas Monthly”.

United States Energy Information Administration (EIA). June 2008b, Preliminary Petroleum Marketing Annual 2007

. United States Environmental Protection Agency (EPA). 1997, “Air Emissions from Scrap Tire Combustion”.

United States Environmental Protection Agency (EPA). 1998, “Development of Comparable Fuel s Specifications”.

United States Environmental Protection Agency (EPA). 2007, “Basic Inform ation”, accessed August 20, 2008 at: http://www.epa.gov/epaoswer/n on-hw/muncpl/tires/basic.htm

.

United States Environmental Prot ection Agency (EPA). 2008a, Cement Sector Trends in Beneficial Use of Alternative Fuels and Raw Materials , October 2008

.

United States Environmental Prot ection Agency (EPA). 2008b, Inventory of U.S. Greenhouse Gas Emissions and Sinks: 1990-2006: Annex 2 Methodology and Data for Estimating CO 2 Emissions from Fossil Fuel Combustion

. United States Environmental Protection Ag ency (EPA). 2008c, “Tire Derived Fuel”, accessed August 20, 2008 at: http://www.epa.gov/epaoswer/n on-hw/muncpl/tires/tdf.htm

.

United States Environmental Protectio n Agency (EPA). 2008d, “Updated 2 006 Kiln List_Recei ved 8_25_2008”, internal EPA document provided by EPA on August 25, 2008.

United States Environmental Protection Agency (EPA). 2009, Combustor survey database in support of the 2009 proposal of the Commercial and Industrial Solid Waste Incinerator (CISWI) standards and the Industrial Boilers Maximum Achievable Control Technology (MACT) standards, April 2009.

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

.

17Scrap Tires



### Appendix 1: Summary of Faci lities Using Tires as Fuel
State Location Company Type of Facility
Alabama Calera Lafarge North America Cement kiln
Alabama Courtland International Paper Corp. Pulp & paper mill
Alabama Theodore Holcim Inc. Cement kiln
Alabama Leeds Lehigh Ceme nt Company Cement Kiln
Alabama Ragland National Cement Cement kiln
Alabama Stevenson Smurfit- Stone Pulp & paper mill
Alabama Demopolis CEMEX Cement kiln
Arkansas Foreman Ash Grove Cement Company Cement kiln
Arkansas Crossett Georgia Pacific Pulp & paper mill
Arkansas Ashdown Domtar, Inc. Pulp & paper mill
Arkansas Pine Bluff International Paper Pulp & paper mill
California Colton California Portland Cement Cement kiln
California Victorville CEMEX Cement kiln
California Redding Lehigh Southwest Cement kiln
California Stockton Stockton Co-generation Industrial boiler
California Lucerne Valley Mitsubishi Cement Cement kiln
California Lebec National Cement Co. of CA Cement kiln
California Kern County Mt. Posco Cogeneration Industrial boiler
Colorado Florence Holcim, Inc. Cement kiln
Connecticut Sterling Exeter En ergy Dedicated tire-to-energy
Florida Auburndale Wheelabrator Ridge Generating Station Utility boiler
Florida Brooksville CEMEX Cement kiln
Florida Brooksville Rinker Materials Cement kiln
Florida Gainesville Florida Rock Cement kiln
Florida Across the state Names not supplied Waste-to-energy (8)
Florida Confidential Pulp & paper mill Georgia Clinchfield CEMEX Cement kiln Georgia Brunswick Georgia Pacific Pulp & paper mill Georgia Rome Temple Inland-Rome Pulp & paper mill Georgia Riceborough Interstate Paper Pulp & paper mill Georgia Dublin SP Newsprint Pulp & paper mill Georgia Cedar Springs Georgia Pacific Pulp & paper mill
Hawaii Oahu AES Hawaii, Inc. Industrial boiler
Idaho Inkom Ash Grove Cement Company Cement kiln
Idaho Boise Boise P&N LLC (Boise Cascade) Pulp & paper mill
Illinois Decatur Archer Daniels Midland (ADM) Industrial boiler
Illinois Oglesby Buzzi Unichem USA Cement kiln
Illinois Grand Chain/Joppa Lafarge North America Cement kiln

Kansas Humboldt Monarch Cement Cement kiln
Kansas Chanute Ash Grove Cement Company Cement kiln Kentucky Owensboro Owensboro Municipal Utilities Utility boiler Kentucky Wickliffe NewPage Corporation Pulp & paper mill

18Scrap Tires

State Location Company Type of Facility
Louisiana Mansfield International Paper Pulp & paper mill
Louisiana Bastrop International Paper Pulp & paper mill
Louisiana Monroe International Paper Pulp & paper mill
Louisiana Deridder Boise Pulp & paper mill Maryland Fredrick Fort Detrick Industrial boiler Maryland Baltimore Wheelabrator Baltimore LP Utility boiler Maryland Joppa Harford Waste-to-Energy Utility boiler
Maine Rumford NewPage Corporation Pulp & paper mill
Maine Bucksport International Paper Pulp & paper mill
Maine Skowhegan SD Warren Pulp & paper mill Michigan Hillman Hillman Power Utility boiler Michigan McBain Viking Energy Utility boiler Michigan Lincoln Viking Energy Utility boiler Michigan Dundee Holcim , Inc. Cement kiln Michigan Wyandotte Wyandotte Power Utility boiler Michigan Filer City Tondu Energy Utility boiler Michigan Grayling Grayling Generating Station Industrial boiler Michigan Escanaba New Page Pulp & paper mill Michigan Quinasec Mananany Paper Pulp & paper mill
Minnesota Satell Versa Paper Pulp & paper mill Mississippi Montecello Georgia Pacific Pulp & paper mill Mississippi Jackson Nucor Steel Electric arc furnace Mississippi Vicksburg (International Paper) Pulp & paper mill
Missouri Columbia University of Mi ssouri-Columbia Industrial boiler
Missouri Kansas City Aquila/ Sibl ey Generating Station Utility boiler
Missouri Cape Girardeau Buzzi Unichem USA Cement kiln
Missouri Joplin Empire Di strict Electric Co. Asbury Power Plant Utility boiler

Missouri St. Joseph Aquila, Inc. - Utility boiler
Nebraska Lincoln Ashgrove Cement kiln
New York Auburn Nucor Steel Auburn Electric arc furnace
New York Fort Drum Black River Electric Utility boiler
New York Niagara Falls Niagar a Generation Industrial boiler
North Carolina Roxboro Primary Energy Industrial boiler

North Carolina Southport Primary Energy Industrial boiler

North Carolina Lumberton Cogentrix Industrial boiler

North Dakota Mandan MDU Heskett Station Utility boiler
Ohio Akron Akron Thermal, LLP Utility boiler
Ohio Chillicothe PH Glatfelter Pulp & paper mill
Oklahoma Ada Holcim, Inc. Cement kiln
Oklahoma Tulsa Lafarge Nort h America Cement kiln
Oklahoma Pryor Lone Star In dustries Inc. dba Buzzi Unicem Cement kiln

19Scrap Tires

State Location Company Type of Facility Oregon Durkee Ash Grove Cement Company Cement kiln Pennsylvania Wampum Cemex Cement kiln Pennsylvania Whitehall Lafarge North America Cement kiln Pennsylvania Allentown Lehigh Cement Cement kiln Pennsylvania Meadville ESSROC Materials Cement kiln Pennsylvania Northampton Northampton Generation (2008 start up) Industrial boiler
South Carolina Hodges Trigen Biopower Industrial boiler

South Carolina Harleyville Lafarge North America Cement kiln

South Carolina Catawba Bowater Pulp & paper mill

South Carolina Hartsville Sonoco Products Company Pulp & paper mill

South Carolina Eastover International Paper Pulp & paper mill

South Carolina Georgetown International Paper Pulp & paper mill

South Dakota Ottertail Power Company Utility Boiler
Tennessee Calhoun Bowater Inco rporated Pulp & paper mill
Tennessee Memphis TVA Allen Steam Plant Utility boiler
Tennessee Knoxville CEMEX Cement Kiln
Tennessee Jackson Gerdau Ameristeel Electric arc furnace
Texas Midlothian Ash Grove Cement, Texas L.P. (f/k/a North Texas Cement) Cement kiln

Texas New Braunfels Cemex of Texas, L.P. Cement kiln
Texas Midlothian Holcim Texas L.P. Cement kiln
Texas Mary Neal Lone Star Cement Cement kiln
Texas Hunter Texas Industries Cement kiln
Texas Midlothian Texas Industries Cement Cement kiln
Utah Leamington Ashgrove Cement kiln
Utah Morgan Holcim Inc. Cement kiln
Utah Grantsville Chemical Lime Company Lime kiln Virginia Richmond Cogentrix Industrial boiler Virginia Portsmouth Southeastern Public Service Authority Industrial boiler Virginia Martinsville Tire Energy Corp (TEC) Industrial boiler Washington Seattle Ashgrove Cement Cement kiln West Virginia Parkersburg Allegeny Power Utility boiler
Wisconsin Cassville Alliant Energy Utility boiler
Wisconsin Sheboygan Alliant Energy Edgewater Generating Station Utility boiler

Wisconsin Ashland Xcel Energy Bayfront Plant Utility boiler
Wisconsin Madison University of Wisconsin Charter Street Plant Industrial boiler

Wisconsin Kaukauna Thilmany Paper Pulp & paper mill
Source: RMA 2009

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