1 

TIRE DERIVED FUEL: 

ENVIRONMENTAL CHARACTERISTICS AND PERFORMANCE

Presented by 

Terry Gray, President 

T.A.G. Resource Recovery 

at 

The First Northeast Regional Scrap Tire Conference 

Albany, New York 

June 15, 2004 

PERSPECTIVE 

 In an ideal world, we would endlessly recover and reuse all resources - and we 

would do so without detrimental impact on our environment. However, we have significant 

differences of opinion about practical compromises required in today's real world. Some 

are fixed on achieving the ideal "perpetual recycling" objective and are unwilling to support 

interim compromises for fear of jeopardizing achievement of the ultimate objective. Others 

recognize the value of resources conserved through interim steps and believe that these 

steps contribute to the evolution of even greater conservation. 

 This debate has impacted virtually all "waste" materials, including scrap tires. Tires 

represent a significant resource. Ideally, a tire's polymerized rubber mixture would be 

perpetually reused. However, today's applications for this material consume less than 15% 

of the waste tires generated annually in North America. These markets are growing slowly 

in spite of intense market development efforts, and even the most optimistic projections 

show less than 30% utilization in 5 years. 

 Unless other applications are embraced and developed, the remainder of this 

resource will be squandered through landfilling or become a stockpiled public liability 

posing public health and environmental hazards. Since no one consciously wants to waste 

a valuable resource, other applications that are compatible with our environment should be 

developed. Avoiding unnecessary consumption of natural energy resources through 

alternative use of waste tires is a worthy objective if it can be done without a counterbalancing negative impact on our environment. For perspective, the following sections 

examine chemical characteristics and historical environmental experience of waste tires as 

an energy resource. 
2 

CHEMICAL CHARACTERISTICS OF SCRAP TIRES

 The chemical characteristics of any energy resource impact its environmental 

acceptability. Tires are a hydrocarbon-based material derived from oil and gas. Some 

inorganic materials are added to enhance reactions or performance properties. Tires have 

a heat content of 7,800 to 8,600 kcal/kg (14,000 to 15,500 Btu/pound), depending on the 

type of tire and degree of wire removal. By comparison, coal that may be displaced by use 

of tires typically contains 5,550 to 7,200 kcal/kg (10,000 to 13,000 Btu/pound). 

 The composition of tires and coal vary depending on type and source. However, 

Exhibit 1 provides representative proximate and ultimate analyses of tire-derived fuel (TDF) 

with 90+% of the reinforcing wire removed and a bituminous eastern US steam coal. 

Proximate analysis defines basic combustion characteristics. Ultimate analysis defines 

elemental composition. 

 A comparison of the proximate analyses indicates that tires offer efficiency 

advantages versus coal. For instance, tires generally have lower moisture content than 

coal. Since energy required to heat and vaporize inherent water is generally nonrecoverable in the energy conversion process, lower moisture content can translate into 

higher energy utilization efficiency. Lower ash content of TDF (without wire) offers a similar 

advantage versus coal. A tire's higher volatile-to-fixed carbon ratio enhances its ability to 

combust rapidly and completely. Based on proximate analysis, tires compare favorably to 

coal as an energy source. 

 

 Based on ultimate analysis, tires offer some additional advantages and 

disadvantages. When compared to many eastern coals, TDF's lower sulfur content 

(especially in terms of pounds/million Btu) offers the potential advantage of decreasing 

SOx emissions. However, many western coals have lower sulfur content. 

 TDF has a lower carbon-to-hydrogen ratio, theoretically reducing carbon dioxide 

greenhouse gas generation since hydrogen converts to water in the combustion process. 

Lower inherent nitrogen content can marginally decrease NOx emissions. 

 The chlorine content of tires is higher in this specific example, but it is comparable to 

many coals. In addition, the chlorine content has been significantly reduced in many newer 

tires as the chlorinated butyl inner liner has been replaced by alternative materials. 

 Elemental ash analysis provided in Exhibit 2 indicates that tires generally contain 

metal concentrations comparable to, or lower than, coal with one notable exception. Zinc 

oxide is added to tires as part of the rubber vulcanization process at levels approaching 1.0 

- 1.5% by weight. Therefore, zinc levels in tires are much higher than coal. Applications 

using tires as an energy resource must be able to control zinc emissions to avoid a 
3 

negative environmental impact. 

 From a chemical standpoint, tires offer both environmental advantages and 

disadvantages versus coal. Therefore, tires must be used in applications that utilize their 

advantages and properly control their disadvantages for them to provide a valuable and 

environmentally-friendly energy resource. 

 HISTORICAL ENVIRONMENTAL PERFORMANCE

Background

 Scrap tires have been utilized as a supplemental energy source in Japan, Europe 

and the United States since the 1970s. The experience base has increased significantly 

during the last 10 - 15 years as tires have been recognized as an acceptable fuel for some 

combustion processes. Applications using scrap tires have broadened to include cement 

kilns, industrial boilers, traditionally-conservative utilities and dedicated electrical generation 

facilities. The following discussion provides examples of demonstrated environmental 

performance for major applications. 

Pulp and Paper Industry

 The pulp and paper industry combusts bark and waste wood in stoker-fired boilers 

to provide steam and power required for processing operations. Wood is combusted on 

moving grates that also transport residual ash from the boiler. Coal, oil or gas can be fired 

into the boiler above the grate to enhance combustion and maintain operating 

temperatures, especially when waste wood moisture content is high from rain. 

 This application utilizes tire derived fuel (TDF) obtained by processing scrap tires 

into uniform, flowable chips less than 2 inches by 2 inches in size. Bead wire is often 

removed magnetically to avoid fouling of grates and ash handling systems. TDF can be 

introduced separately or as an integral part of the wood mixture with relatively simple, 

inexpensive metering systems. TDF's high volatile carbon content enhances combustion 

of wood on the grate and improves fuel efficiency. 

 The environmental impact associated with use of TDF in this application is 

dependent upon characteristics of the displaced fossil fuel and system environmental 

control equipment. The two predominant factors controlling environmental acceptability are 

SOx and particulate (zinc oxide) emissions. SOx emissions may decrease if TDF 

displaces coal or oil with higher sulfur content. Alternatively, SOx can be controlled by 

scrubbers present in some systems, especially if the scrubbers operate at a neutral or 

basic pH. Particulate emissions can be controlled by electrostatic precipitators (ESPs) or 

baghouses. In general, many environmentally acceptable applications occur when coal is 
4 

displaced in systems with baghouses or ESPs. 

 Based on data compiled by the Rubber Manufacturers Association, 17 U.S. paper 

mills used approximately 26 million scrap tires as TDF in 2003 in compliance with 

applicable regulations, and others are undertaking testing. Usage has fluctuated, but high 

cost of fossil fuels has led to a significant resurgence in TDF usage in paper mills as new 

mills have completed environmental testing and existing users have maximized 

consumption, especially in southeastern facilities. Usage during 2004 is expected to 

exceed 30 million waste tires 

 The International Paper facility in Bucksport, Maine has been one of the largest 

users of TDF since 1990. Their boiler is capable of consuming up to 3.5 tons of TDF per 

hour (14.5% by heat input) to produce almost 500,000 pounds of steam per hour. 

 Exhibit 3 provides environmental data associated with performance testing 

conducted at this site. A baseline test was conducted using their normal mixture of gas, 

bark, coal and sludge. TDF was then substituted for coal at levels representing 6.3%, 

10.3%, and 14.5% of heat input. At the maximum TDF level, NOx, SOx and total 

hydrocarbon emissions remained virtually unchanged, while particulate matter increased 

6%. Among the metals, beryllium and chromium decreased, lead remained below 

detection limits and cadmium increased. Zinc increased significantly percentage-wise, but 

total quantities remained acceptable. Overall particulate emissions remained well within 

acceptable limits. 

 Performance data has also confirmed environmental acceptability of TDF in similar 

paper mills and industrial boilers in 20 states. Several of these states (including Oregon, 

Washington, California and Florida) are recognized for their environmental sensitivity and 

rigorous regulatory enforcement. However, these applications must be carefully screened 

to define facilities capable of using TDF within environmentally acceptable limits. Only a 

small percentage of industrial boilers have the required combination of system design, 

permitting conditions and fuel usage conducive to appropriate TDF usage. 

Public Utility Boilers

 During 2003, there were at least 29 industrial and utility facilities consuming the 

equivalent of 40 million tires according to RMA. This industry segment continues to 

increase with additional growth projected in the future. 

 TDF can only be used efficiently in specific types of utility boilers (primarily cyclone, 

fluidized-bed and stoker-grate units) offering adequate retention time for complete 

combustion of nominal 1 inch (minus 2 inch) TDF. This is the smallest TDF material that 

can generally be produced at costs competitive with coal and other fossil fuels. These 

units consume large quantities of fuel, so small percentages of TDF (2-4%) can use up to 
5 

5,000,000 tires/year in a single boiler. 

 Several factors influence use of TDF in the utility industry, including: 

 (1) Canada and the United States executed agreements designed to reduce the impact 

of acid rain through mandatory reductions in SOx emissions. Major coal-fired 

utilities using Midwestern and eastern coals have been under intense pressure to 

achieve mandatory reductions at minimal cost to their customers. They are faced 

with purchasing expensive low-sulfur coal or making substantial capital investments 

in additional air pollution control equipment. As a direct result, conservative utilities 

have begun to recognize the potential value of TDF as an alternative fuel with a 

lower sulfur content than some local coal. Use of TDF offers an opportunity to 

concurrently reduce both SOx emissions and fuel costs, while providing a partial 

solution to historical scrap tire disposal and stockpiling problems. 

 (2) Deregulation of utilities has been a double-edged sword in terms of TDF usage. 

Some older marginal units that were using TDF have been shut down, decreasing 

TDF usage. However, more utilities are considering TDF usage as a method of 

cost reduction in an extremely competitive environment. In addition, new fluidized 

bed boilers have begun to use TDF with outstanding environmental performance. 

 (3) The Clean Air Act Amendment has not yet been fully developed, but it could 

significantly impact all facilities using solid fuels. It could force conversion to oil and 

gas as an alternative to expending millions of dollars to achieve conformance on 

existing coal fuel. Depending on the final form of this regulation, all solid fuels, 

including TDF, could be negatively impacted. 

 TDF usage in utility cyclone boilers is expanding. Pulverized coal is introduced 

tangentially into a large cylindrical chamber and combusted, with ash falling into a fluid 

collection system at the bottom. TDF must generally meet stringent size restrictions (minus 

2 inches in all dimensions, averaging 1 inch or less) to enhance complete combustion and 

material handling through coal systems. 

 Otter Tail Power Company has been using up to 60,000 tons of TDF per year at its 

plant in Big Stone, South Dakota. TDF has reportedly proven to enhance combustion 

control and efficiency when added to their primary low-Btu lignite fuel. The facility operates 

in compliance with all applicable regulations, but detailed data is not available. 

 Wisconsin Power and Light has conducted extensive tests using TDF as a 

supplemental fuel in its cyclone boiler at Beloit. The system has an ESP for particulate 

control. Comparative criteria pollutant data is provided in Exhibit 4. Particulate, SOx, 

hydrochloric acid and hydrofluoric acid concentrations decreased with use of 7% TDF. 

However, NOx, CO and hydrocarbons increased, but remained within applicable permit 
6 

limits. WP&L constructed its own TDF processing facility based on economics and supply 

considerations, but encountered initial difficulty in achieving production expectations. In 

addition to these examples, TVA and Illinois Power have conducted extensive trials and 

are using TDF in cyclone boilers. 

 Circulating fluidized bed boilers represent one of the newer systems designed to 

minimize environmental impact from use of solid fossil fuels. High turbulence and uniform 

heat distribution allow fluidized beds to operate at lower temperatures to minimize NOx 

formation. Ammonia injection may also be used for supplemental NOx reduction. 

Limestone is commonly used as the circulating bed media, providing efficient SOx control 

through integral mixing with combustion gases. Sophisticated baghouses and/or 

electrostatic precipitators provide particulate removal. 

 These systems represent environmentally-viable candidates for use of nominal 1-

inch TDF. Stockton Cogen in Stockton, California conducted extensive trials with financial 

assistance from the California Integrated Waste Management Board to define the 

emissions characteristics associated with use of up to 20% TDF (by heat). The results of 

this analysis are compared to the facility's pre-existing lower (state or local) permit limit in 

Exhibit 5. All emissions were well within permit limits, with particulate and hydrocarbons 

being less than 25% of established limits. 

 Tires have even been used as a primary fuel in dedicated, specially designed power 

boilers in California and Connecticut using 5 million and 10 million tires per year, 

respectively. After some initial difficulties associated with scale up of this technology, these 

facilities have reportedly operated in compliance with strict new-source performance 

criteria. The Connecticut facility is still operating, but the California plant has been shut 

down due to economic and political factors associated with a major fire (initiated by a 

lightening strike during a storm) in an adjacent stockpile that was being abated by 

supplying tires to the facility. 

Cement Kilns

 Scrap tires have been used as a supplemental fuel in cement kilns in Europe and 

Japan since the 1970s and currently represent the largest application in North America. 

Only Calvaras Cement in California consumed waste tires 15 years ago. In 2003, 42 

facilities used whole tires or TDF as a supplemental energy source in 62 kilns, consuming 

53 million waste tires according to RMA. Others are conducting performance tests 

targeted at future use. 

 

 Some factors impacting current interest in scrap tires as a supplemental energy 

source in kilns deserve mention: 

Logistics - Kilns are often located near market population centers with large waste tire 
7 

quantities and difficult tire disposal problems, providing efficient logistics. 

Energy Intensity - Kilns are energy intensive, allowing consumption of 500,000 - 1,500,000 

million tires/year/kiln. TDF energy cost savings versus fossil fuels can provide a 

competitive economic advantage. 

Rigorous Combustion Conditions - A unique combination of high temperatures, long 

residence times and turbulent air flow promote complete combustion of organic 

compounds contained in tires. 

Inherent SOx Control - Limestone used in cement manufacture is commonly used in APC 

systems to absorb SOx, providing inherent SOx control. 

Ash Utilization - Ash resulting from tire combustion becomes an integral component of the 

cement product, eliminating ash disposal requirements. 

Steel Use - Reinforcing wire is constructively consumed as a replacement for purchased 

natural resources or alternative materials containing iron. 

Broad Applicability - Demonstrated technology allows use of tires in older long kilns, as well 

as newer preheater and precalciner units. Many kilns use whole tires without additional 

processing. 

 

 Although these factors encourage use of tires as a supplemental fuel in kilns, 

demonstrated performance is a critical consideration in establishing environmental 

acceptability of this application. Extensive environmental data has been generated for a 

variety of kiln configurations and fuel displacements. Time limitations preclude discussion 

of all available data, but several examples are included. 

 Exhibit 6 provides comparative data resulting from comprehensive tests conducted 

by Florida Crushed Stone. TDF representing 14% energy displacement was introduced 

into the riser section of their preheater kiln. Particulate and SOx emissions declined with 

TDF use. Volatile organics increased but semi-volatile organics decreased by an even 

greater margin, resulting in a net reduction in organic emissions. Changes in metal 

concentrations were nominal. Comprehensive testing of dioxins and furans showed a net 

reduction of over 50% with TDF use. Florida Crushed Stone is currently using 

approximately 800,000 scrap tires per year as an alternative energy source in full 

compliance with all applicable regulations. 

 Performance results for Ashgrove Cement's kiln in Durkee, Oregon are provided in 

Exhibit 7. Emissions of particulate, SOx, chlorides and all heavy metals declined or 

remained constant. Total hydrocarbons increased about 10%, but polynuclear aromatics 

declined about 10%. This facility completed a comprehensive PSD review associated with 
8 

its use of other waste fuels, and is fully permitted for waste tire usage. This plant's 

performance is accepted in one of the most environmentally-sensitive states in the U.S. 

 Several of the southwestern cement plants have undergone extensive testing. 

Results of California Portland Cement Company's emissions results for its Colton plant are 

summarized in Exhibit 8. Some criteria decreased with use of tires, while others increased. 

 For example, total particulate increased less than 10%, while non-methane hydrocarbons 

decreased about 18%. Recognized carcinogens like benzene and toluene decreased. 

Total PCDD/PCDF materials increased nominally in quantity. Most PCBs and PAH's 

declined with tire usage, while hydrochloric and hydrofluoric acids increased. Hexavalent 

chromium, barium, cadmium lead and nickel emissions declined, while zinc and mercury 

increased. While the most critical impact will probably depend upon the reviewer's 

perspective, most changes were relatively minor and the net impact appears to be 

relatively balanced. 

 In order to place these relative impacts into a technically-structured perspective, Cal 

Portland engaged an experienced contractor to conduct a comparative Health Risk 

Assessment using the latest versions of the ISC dispersion model and ACE health effects 

model specified by the California EPA. Based on this evaluation, the individual 

carcinogenic risk declined 47% with TDF usage, while the non-carcinogenic health effects 

resulting from short-tern exposure (acute hazard index) fell 94% and the non-carcinogenic 

health effects of continuous exposure (chronic health impact) decreased 72%. None of us 

like to contemplate any exposure, and some may even question the assessment 

methodology, but most of us prefer reductions like those demonstrated at Cal Portland. 

 Cement kilns constructively utilize more waste tires than any other single 

application. Kilns are an important component of waste tire management in most states 

considered to have successful programs. Any state that is not fully utilizing its waste tire 

resource may wish to objectively evaluate the environmental and economic merits of this 

application. 

 SUMMARY

 Scrap tires can be an environmentally-compatible alternative energy resource when 

used in appropriate applications. Energy utilization is an important component of 

successful scrap tire management programs within the U.S., allowing this resource to be 

used rather than wasted. The net result has been substantial conservation of nonrenewable fossil fuels. When the demonstrated performance of tires as an energy 

resource is objectively evaluated, many jurisdictions have concluded that our environment 

is better served by recognizing the value of this resource rather than wasting it while 

waiting for ideal solutions. Good programs recognize the importance of diverse 

applications. 
9 

Acknowledgement: This document was written by Terry Gray, President of T.A.G. 

Resource Recovery, with guidance and peer review from EPA and industry members of 

the EPA RCC TDF Subcommittee. 
10 

EXHIBIT 1 

COMPARATIVE CHEMICAL 

CHARACTERISTICS 

CHARACTERISTIC

EASTERN 

BITUMINOUS 

COAL 

 TDF (90+% 

WIRE FREE) 

 

PROXIMATE ANALYSIS (% AS RECEIVED) 

 

 

MOISTURE 7.76 0.62 

ASH 11.05 4.78 

VOLATILE 34.05 66.64 

FIXED CARBON 47.14 27.96 

 TOTAL 100.00 100.00 

 

 

ULTIMATE ANALYSIS (% AS RECEIVED) 

 

 

CARBON 67.69 83.27 

HYDROGEN 4.59 7.09 

NITROGEN 1.13 0.24 

SULFUR 2.30 1.83 

ASH 11.05 4.78 

MOISTURE 7.76 0.62 

OXYGEN (by 

difference) 5.48 2.17 

 TOTAL 100.00 100.00 
11 

EXHIBIT 2 

ELEMENTAL METALS ANALYSIS 

(%, OXIDE FORM)

ELEMENT 

(OXIDE) 

EASTERN 

BITUMINOUS 

COAL 

TDF (90+% 

WIRE FREE) 

 

Aluminum 2.29 <0.01 

Barium - nd 

Cadmium - 0.0006 

Calcium 0.36 0.378 

Chromium - 0.0097 

 

Iron 2.09 0.321 

Lead - 0.0065 

Magnesium 0.08 <0.01 

Manganese - <0.01 

Phosphorous 0.07 <0.01 

 

Potassium 0.22 <0.01 

Titanium 0.09 <0.01 

Silicon 5.30 0.516 

Sodium 0.05 <0.01 

Strontium - <0.01 

Zinc 0.01 1.52 

 

Chloride - 0.149 

Fluoride - 0.001 

 
12 

EXHIBIT 3 

COMPARATIVE EMISSIONS 

INTERNATIONAL PAPER MILL 

BUCKSPORT, MAINE 

(EXPRESSED AS POUNDS/MM BTU) 

CRITERIA BASELINE 14.5% TDF 

(BY HEAT) 

PERCENT 

CHANGE 

 

N O x 0.274 0.273 0 

S O x 0.508 0.51 0 

PARTICULATE 0.053 0.056 6 

TOTAL 

HYDROCARBONS 1.17 E-3 1.18 E-3 1 

 

BERYLLIUM 1.06 E-6 0.73 E-6 -31 

CADMIUM 0.60 E-6 0.78 E-6 30 

CHROMIUM 12.1 E-6 6.36 E-6 -47 

LEAD <10 E-6 <10 E-6 0 

ZINC 0.26 E-3 2.56 E-3 885 
13 

EXHIBIT 4 

COMPARATIVE EMISSIONS 

FROM A CYCLONE BOILER 

WISCONSIN P&L 

CRITERIA UNITS BASELINE 7% TDF 

(BY HEAT) 

PERCENT 

CHANGE 

 

N O x LB/MM BTU 0.79 0.91 16 

S O x LB/MM BTU 1.14 0.87 -34 

PARTICULATE LB/MM BTU 0.52 0.14 -73 

 

CO LB/HR 1.52 7.26 377 

TOTAL 

HYDROCARBONS LB/HR 5.16 10.27 99 

 

HCL LB/HR 25.27 19.89 -23 

HF LB/HR 1.86 1.34 -28 
14 

EXHIBIT 5 

EMISSIONS FROM A 

CIRCULATING FLUIDIZED BED BOILER 

STOCKTON COGEN 

(STOCKTON, CALIFORNIA) 

(EXPRESSED AS POUNDS/HOUR) 

CRITERIA 20% TDF 

 (BY HEAT)

LOWER 

PERMIT 

LIMIT 

 

N O x 25.06 39.00 

 

S O x 33.40 59.20 

 

PARTICULATE 2.19 10.00 

 

CO 20.90 22.90 

TOTAL 

HYDROCARBONS <0.38 1.88 
15 

EXHIBIT 6 

ENVIRONMENTAL PERFORMANCE DATA 

TDF INTRODUCTION INTO THE RISER SECTION 

OF FLORIDA CRUSHED STONE'S PREHEATER KILN 

(expressed as pounds/hour) 

CRITERIA BASELINE 14% TDF 

PARTICULATE 56.80 52.21

 

S O x 595.15 551.30

 

VOLATILE ORGANICS 

 Acetone 0.02 0.02

 Benzene 0.08 0.15

 Toluene 0.01 0.20

 Chloromethane <0.01 0.03

 Others <0.03 0.04

 TOTAL 0.15 0.44

 

SEMI-VOLATILE ORGANICS (C16-C18) 5.01 0.90

 

METALS 

 Aluminum 6.86 8.13

 Arsenic <0.004 <0.004

 Barium 0.02 0.02

 Cadmium <0.005 0.01

 Chromium 0.02 0.01

 Cobalt 0.01 <0.002

 Copper 0.03 0.03

 Iron 1.39 1.30

 Lead 0.13 0.04

 Magnesium 0.50 0.55

 Mercury 0..04 0.01

 Molybdenum 0.02 0..02

 Nickel <0.02 <0.02

 Selenium <0.004 <0.004

 Silver <0.009 <0.009

 Titanium 0.22 0.26

 Vanadium <0.02 <0.02

 Zinc 3.12 1.68
16 

EXHIBIT 6 (CONTINUED) 

ENVIRONMENTAL PERFORMANCE DATA 

TDF INTRODUCTION INTO THE RISER SECTION 

OF FLORIDA CRUSHED STONE'S PREHEATER KILN 

(expressed as pounds/hour) 

CRITERIA 

 

AVG EMISSION 

RATE (10 E-6 

LBS/HR) 

EQUIV 2378-TETRA 

DIOXIN EMISSIONS 

(10 E-6 LBS/HR) 

 COAL 14% TDF COAL 14% TDF 

DIOXINS 

 2378-tetra 1.00000 0.004 ND 0.004 ND 

 12378-penta 0.50000 0.035 ND 0.017 ND 

 123478-hexa 0.04000 0.048 ND 0.002 ND 

 123789-hexa 0.04000 0.084 ND 0.003 ND 

 123678-hexa 0.04000 0.125 ND 0.005 ND 

 1234678-hepta 0.00100 1.210 0.062 0.001 <0.001 

 octa 0.00000 5.221 1.100 0.000 0.000 

 other tetra 0.01000 0.308 0.061 0.003 0.001 

 other penta 0.00500 0.473 0.079 0.002 <0.001 

 other hexa 0.00040 0.766 0.114 <0.001 <0.001 

 other hepta 0.00001 1.693 0.114 <0.001 <0.001 

 SUBTOTAL 9.667 1.530 0.037 0.001 

 

FURANS 

 2378-tetra 0.10000 0.096 0.061 0.010 0.006 

 12378-penta 0.10000 0.024 ND 0.002 ND 

 23478-penta 0.10000 0.036 ND 0.004 ND 

 23478-hexa 0.01000 0.048 ND <0.001 ND 

 123678-hexa 0.01000 0.024 ND <0.001 ND 

 234678-hexa 0.01000 0.024 ND 

<0.001N

D 

 123789-hexa 0.01000 ND ND ND ND 

 234678-hepta 0.00100 0.060 ND <0.001 ND 

 234789-hepta 0.00100 ND ND ND ND 

 octa 0.00000 0.048 ND 0.000 ND 

 other tetra 0.00100 0.204 0.149 <0.001 <0.001 

 other penta 0.00100 0.130 0.088 <0.001 <0.001 

 other hexa 0.00010 0.006 0.009 <0.001 ND 

 other hepta 0.00001 0.072 ND <0.001 ND 

 SUBTOTAL 0.883 0.307 0.017 0.006 

 

TOTAL (10E-6 LB/HR) 10.550 1.837 0.054 0.007 
17 

EXHIBIT 7 

ENVIRONMENTAL PERFORMANCE DATA 

TDF INTRODUCTION INTO RISER SECTION 

OF ASHGROVE CEMENT'S PREHEATER KILN 

CRITERIA UNITS BASELINE 9-10% TDF 

PERMIT 

LIMIT 

 

PARTICULATE lbs/hr 5.27 4.83 18 

 

S O x lbs/hr <1.5 <1.2 6.3 

 

CHLORIDES lbs/hr 0.268 0.197 NA 

 

TOTAL 

HYDROCARBONS lbs/hr 3 3.3 NA 

 

PNA lbs/hr 0.0058 0.0053 NA 

 

HEAVY METALS 

 Arsenic micrograms 0.2 0.2 NA 

 Cadmium " 3 2 NA 

 Chromium " 30 ND NA 

 Nickel " 30 ND NA 

 Zinc " 35 35 NA 

 Copper " 37 13 NA 

 Lead " ND ND NA 

 Iron " 400 200 NA 

 Barium " ND ND NA 

 Vanadium " ND ND NA 

 
18 

EXHIBIT 8 

ENVIRONMENTAL PERFORMANCE DATA 

 

CALIFORNIA PORTLAND CEMENT KILN 

(expressed as pounds/hour) 

CRITERIA EXPONENT BASELINE 12%TDF

 

PARTICULATE 7.35 8.01 

 

N O x (ppm) 208.80 104..2 

 

CO (ppm) 104.20 159.30 

 

VOLATILE ORGANICS 

 Acetaldehyde 0.34 0.05 

 Benzene 2.65 2.29 

 Formaldehyde 0.88 0.11 

 Toluene 3.98 3.17 

 Dichloromethane E-3 1.79 0.87 

 O-xylene E-3 1.89 2.14 

 Trimethyl benzenes E-3 1.56 3.99 

 

METALS 

 Antimony E-4 2.32 <2.28 

 Arsenic E-4 4.05 0.85 

 Barium E-3 1.20 0.48 

 Cadmium E-4 2.27 1.77 

 Chromium (Total) E-4 3.44 3.94 

 Chromium (Hexavalent) E-4 2.33 1.13 

 Copper E-3 1.11 0.72 

 Lead E-3 1.19 0.59 

 Manganese E-3 1.96 2.06 

 Mercury E-3 4.54 8.33 

 Nickel E-4 5.81 3.00 

 Selenium E-4 ND<1.97 ND<6.54 

 Silver E-5 ND<3.94 <4.55 

 Thallium E-5 <2.52 <2.47 

 Zinc E-3 4.71 9.41 

 
19 

EXHIBIT 8 (CONTINUED) 

ENVIRONMENTAL PERFORMANCE DATA 

 

CALIFORNIA PORTLAND CEMENT KILN 

(expressed as pounds/hour) 

CRITERIA EXPONENT BASELINE 12%TDF 

 

NON-METHANE 

HYDROCARBONS 18.16 14.81 

 

PCDD/PCDF E-6 1.58 1.93 

 

2378 TCDD TOX 

EQUIV E-8 1.05 1.68 

 

PCB's E-6 3.16 2.89 

 

PAH E-2 4.31 3.44 

 

HCl <0.017 0.43 

 

HF 0.016 0.024