## Air Quality Technical Analysis Report
Review of Submittals Supporting the Holcim (US) Inc. Tire s Combustion Proposal

Prepared for: Montana Department of Environmental Quality P.O. Box 200901 Helena, Montana 59620

Prepared by: Lorenzen Engineering, Inc. P.O. Box 65 Jefferson City, MT 59638

December 2004

## Table of Contents

1. Introductio n
............................................................................................................................... ........... 1 1.1 Objective

............................................................................................................................... ....... 1 1.2 Materials R e viewed

..................................................................................................................... 1 1.3 Organization of Report

................................................................................................................ 2 2. Data Adequacy Review

........................................................................................................................ 3 2.1 Em issions Inventor y Data Adequacy Review

............................................................................. 3 2.1.1 Criteria Pollutant Em issions Inventor y ............................................................................... 3 2.1.2 HAP and Air Toxic Em issions Inventor y ........................................................................... 3 2.2 Additional Information Provided by Hol c i m
............................................................................... 5 2.3 Dispersion Modeling Adequacy Review

..................................................................................... 5 3. Review of Emissions Inventor y Meth od s
............................................................................................ 6 3.1 Em issions Estimation Methodol og y ............................................................................................ 6 3.2 Tire-burning Em issions Inventor y Database

............................................................................... 7 3.3 Esti m a ting Emissions from Kiln Upset s
...................................................................................... 8 4. Criteria Pollutant Em issions Inventor y .............................................................................................. 11 4.1 Carbon Mon oxide

...................................................................................................................... 11 4.2 Sulfur Dioxi d e
........................................................................................................................... 12 4.3 Nitrogen Oxi d es
......................................................................................................................... 12 4.4 Particulate M a tter and ESP Efficiency

...................................................................................... 13 5. Hazardous and Toxic Air P o llutant Em issions Invento r y .................................................................. 15 5.1 Increm ental HAPs Increase fro m Burning Tires

....................................................................... 15 5.2 Expanded E m issions Inventor y ................................................................................................. 16 5.3 Reco mmended Adjustm e nts in Em issions Inventor y ................................................................ 16 5.4 Summary of HAPs E m i ssi on Estim at es
.................................................................................... 18 6.0 Air Dispersio n Modeling Review

.................................................................................................. 21 6.1 AERMOD Modeling S y ste m
..................................................................................................... 21 6.2 AERMET Meteorological Data Processing

............................................................................... 21 6.3 Sources and Modeling Para m e t e rs
............................................................................................ 22 6.4 Modeling Re ceptors

................................................................................................................... 24 6.5 Summary of Modeling Re sults

.................................................................................................. 25 7. Conclusions and Reco mmendations

................................................................................................... 39 8. Referen ces
............................................................................................................................... ........... 40

i

### List of Tables
TABLE 1: Potential Annual Kiln Criteria Pollutant Em issions ..............................................11 TABLE 2: Estim ated Kiln HAP Emissions .............................................................................19 TABLE 3: Gallatin County Industrial Em issions Sources ......................................................24 TABLE 4: Peak Model Results................................................................................................31



### List of Figures
FIGURE 1: W i nd Rose for Holcim ’s Triden t Meteorological Monitoring Station ..................23 FIGURE 2: Fine Receptor Grid and Boundary Recepto rs ........................................................26 FIGURE 3: Expanded Modeling T e rrain and R ecepto r Grid ....................................................27 FIGURE 4: Annual Average Dispersion Coefficients ..............................................................29 FIGURE 5: Peak 1-hour Averag e Dispersion Coefficients .......................................................30



### Appendices

APPENDIX A: Baseline Em issions Inventory APPENDIX B: Cum u lative Em issions Inventory APPENDIX C: Em issions Factor Com p arison APPENDIX D: Final Dispersion Modeling Protocol and Report

ii

## 1. Introduction Holcim Ce m e nt Company (Holcim ) is proposing to use tires as fuel in their Trident cem ent kiln. Montana D e partm e nt of Environmental Quality (DEQ) is in the p r o cess of preparing an Environm ental Im pact Statem ent (EIS) to identif y potential impacts from th e proposed project.
Holcim is c u rrently au thorized to b u rn natu ral gas, coal, petroleum coke , or any combination of these as a fuel for the kiln. The perm it applic ation requests the m i d-k iln com bustion of whole waste tires for up to 15 pe rcent of the total fuel heat input to the kiln (on a Btu basis). Burning tir es f o r f u el will chang e the am ount and composition of air contam inant em issions f r om the cem ent kiln stack and m a y affect the concentra tion of contam inants in the cem ent kiln dust (CKD). 

### 1.1 Objective The objec tiv e of this Air Quality Te c hnical Analysis Repor t is to repor t o n the third

- p a rty review of Holcim ’ s tire-burning em issions estim a tes and air quality im pact analyses. Lorenzen Engineering, Inc. has worked with DEQ and DEQ’s risk assessm ent contractor throughout the EIS process. The results and conclusions presente d in this report have be en discussed with other m e mbers of the EIS team. This report is intended to supplem ent m a terial that is already part of th e public record and does not rep eat infor m ation available in the o r igin a l docum ents. Holcim has es tim ated the total em issions from the kiln using the current fuel mi x, the total potential em issions using tires as a supplem ental fuel, and the change in em issions due to tire com bustion. Holcim has also prepar ed an d subm itted com puteriz ed air disp ersion m o deling r e sults to show am bient air contam inant concentrations resultin g from the cem ent plant. 

### 1.2 M aterials Reviewed Holcim has been workin g with DEQ since 2001 to obtain a Montana air quality perm it alteratio n allowing them to proceed with their tire-burn i ng proposal. In January 20 04, Holcim com p iled all of

the re leva nt applica tio n subm ittals into a sing le docum ent titled “Application for Alteration to Air Quality Permit #0982-10” (ref. 1)

. The compilation pro v ides a clear record of infor m ation subm itted by Holcim and decisions m a de regard ing the prop osed projec t. This report will ref e r to the pe rm itting com p ila tion ( r ef . 1) rathe r than r e f e rring to e a rlier subm ittals.
Holcim subm itted additiona l inf o r m ation rega rding em iss i ons inv e ntory and a i r dispe r sion modeling du ring the E I S review p r oc ess. Th e ad dition a l sub m ittals a r e included as a ppendices to this report. Expanded em issions inventories are included in Appendices A and B. A com p arison of Holci m ’s estim ated em issions and source test da ta is contained in Appendix C. Appendix D is Holcim ’s final m odeling report. Holcim provide d th e modeling f i le s elec tron ic ally and the y were verified as part of the review process. Holcim ’s final modeling results have been used to genera te illu stra tive f i gu res f o r this r e port.

1

### 1.3 Organization of Report This techn i cal analy s is report in clud es a critical review of the contam inant em issions inform ation provided by Holcim both in the original perm it application m a terials and in subsequent subm ittals. It exam ines the source of e m issions inform at ion and the m e thodology used to estim ate em issions f r om the Trid ent kiln. Em issi ons estim ates from the current fuel m i x and the proposed fuel m i x are included in this report. Dispersion modeling review in this report in cludes evaluation of the choice of m odel , applic ability of the m e teorolog i cal data and treatm e nt of terr ain features. The report also includes graphical representations of the m odeling results. The Air Quality Te chnic a l Analys is Report is o r ganized in the f o llowing m a in sectio ns: 1. Introduction 2. Data Adequacy Review 3. Review of Em issions Inventory Methods 4. Criteria Pollutant Em issions Inventory 5. Hazardous and Toxic Air Pollutant E m issions Inventory 6. Air Dispersion Modeling Review 7. Conclusions and Recomm endations 8. References

2

## 2. Dat a Adequacy Review The f i rst ste p in the EIS air quality analys is wa s review of the project file and all infor m ation subm itted in support of the perm it application. The purpose of this data adequacy review was to determ ine whether suf f i cient inf o rm ation exis ted in th e pro j e c t f i le f o r a com p lete evaluation of im pacts from the tire-burning proposal. Following the data adequacy review, DEQ requeste d additional information from Holcim to be used to co mplete the EIS. Scoping comm ents re lating to air quality were also rev i ewed and inform ation has been included in this report to address these comm ents. 

### 2.1 Emissions Inventory Data Adequacy Review Holcim subm itted em i ssions inv e ntory inform ation for criteria p o llutants, h azardous air pollutants (HAPs) and other toxi c air po llu tants tha t a r e c o mm onl y related to tire burning in kilns. 

### 2.1.1 Criteria Pollutant E m issi ons Inve nt ory Holcim subm itted em issions es tim ates f o r total ki ln cr ite r ia po llu tan t em issions as well as em ission changes resulting from the tire-burning proposal. Gaseous criteria air pollutants are carbon m o noxide (CO), sulfur dioxide (SO 2 ), ozone and nitrogen dioxide (NO 2 ). Lead (Pb) and particula t e m a tter sm aller than 10 m i crons ( P M 10 ) a r e s o l i d or par t ic ulate ph ase criteria pollutants. Volatile organic com pounds (VOC) are regulated because they lead to the form ation of ozone in the atm o sphere. The criteria pollutant em issions inventory was found to be ade quate for EIS review and no additional infor m ation was reque sted. Criteria pollutant em issions are regulated through Montana’s air quality p e rm itting pro cess. Holcim has conducted em issions tests on the cem ent kiln stack, a s requir e d b y DEQ, to determ ine th e em issions o f criter i a a i r pollutan t s. Em issions from the Trident facility have been estim ated by DEQ and Holcim and are included in Holcim ’s proposed pre-construction perm it #0982-11 (ref. 2). 

### 2.1.2 HAP and Air Toxi c Emissions Inventory Holcim estim a ted HAPs em issions f r om tire bu rni ng for us e in th eir health risk ass e ssm ent (ref. 1). The HAPs and air toxics inform ation was also used in DEQ’s subsequent risk study titled, “Human Health and Ecological Risk assessment of Kiln-Related Emissions at the Holcim Trident Cement Plant (re f. 3) .”
The risk as sessm ent considers all HAPs as ch em i cals of potential co ncer n (COPCs) (ref. 3). Holcim added zinc to th e risk assessm e nt calcula tions, even though it is no t a HAP and is exem pt from consideration under Montana regulations. Holcim chose to inc l ude zinc be cause it is a known constituen t in tires and was noted as a po te ntial concern by the inte rested public (ref. 1).
Holcim initially e s tim ated only th e increm ental incre a se in HAP em issions resu ltin g f r om the addition of tires to the kiln fuel stream . Although the origin al em issions inventory produced conservative estim a tes of the em issions increase, it did not provide info rm ation abo u t the to ta l

3HAP e m issions from the kiln. Through the data ad equacy review, it becam e clear that additional inventory infor m ation would be needed for a comp lete rev i e w of the change in plan t em issions resulting from the proposed project. Scoping comme nts indicated that the public was interested in th e em issions resulting f r om all kiln raw m a terial feeds as well as coal, coke and tire com bustion. In addition to m i ned lim e stone, silica and shale, Holcim uses recycled glass as a silica sou r ce and recycled sm elter slag as an iron source. Based on public comment and review of referen ce m a terials, DEQ determ ined that a risk assessm ent based only on the increm ental change in em issions is not adequate. In a health consultation prepared for a sim ilar project in Colorado, the U.S. Departm e nt of Health and Hum a n Services Agency for Toxic S ubstances an d Disease Registry (AT S DR) reach ed the sam e conclusion (ref. 4). ATSDR reviewed the risks from that project and found that the regulatory agency “had analyzed stack test data with and w ithout the burning of tires at other cem e nt kilns and calculated the percent change in e m issions.” In their report, ATSDR stated, “It is not the percent of change that is significa nt – it is the dose of a particul ar chem ical th at is important. ... We do not agree with the com p arative risk m e t hodology used in the report to determ ine if the stack em issions would adversely a ffect public health (ref. 4).” DEQ requested that Holcim provide an em issions inven t ory to inc l u d e tota l kiln em issions, including em issions from tire burning. In respon se, Holcim developed an em ission inventory for the kiln emissions us in g all curr en tly perm itte d f u els and kiln f eeds. The existin g inventory (without tires) is referred to as the “baseline” inventory and is included in Appendix A of this report. Appendix A also includes a m e m o pr ovided by Holcim explaining the em issions inventory procedures. The baseline inventory represents potential em issions from curre ntly allowed k iln f u els an d feeds. It con t ains es tim ated em issions from use of coal and coke as fuel, with recycled glass used as a source of silica t e in the kiln f e e d. Holcim provided tw o versions o f the baselin e invento r y, one with a typical production rate of 315,000 tons of clinker per year an d one with the m a xi m u m allowable production rate of 425,000 tons of clinke r per year. The baseline em issions inventory is based on the 425,000-ton allowable production rate.
Holcim also provid e d a “cum u lative ” em issions i nventory using allowed k iln raw m a ter i al f e eds and using tires as 15% of the total fuel st re a m . The cu mulative e m issions inventory a n d accom p anying m e m o are in cluded in Append ix B of th is repo rt. T h e cum u lative em ission inventory includes estim a ted e m issions from the use of coal, coke and tires as fuel, and all approved k i ln f eed m a teria l s. The cum u lativ e inventory represents the m a xi m u m potential em issions of HAPs f r om the kiln with the us e of tires a s f u el. The cum u lative em issions inventory is based on a m a xi m u m a nnual pr oduction rate of 425,000 tons of clinker. Following s u bm ittal of the bas e line and cu mula tive e m issions inventor ies, the EIS te am concluded that the HAPs em issions inventory in form ation was adequate for the EIS review.

4

### 2.2 Additional Information Provided by Holcim In addition to the revised em issions inventor ies, DEQ requested that Holcim provide the f

o llowing in f o rm ation to allow the EIS team to f u lly evalu a te the em issions inven t ory. All the data was provided and was used in th e air qu ality technical an alysis.

• Design and operation infor m ation for the part iculate contro l equipm ent for the Trident kiln,

• HAP stack test re sults f o r the Holc im kiln.

• Coal analys es for the Holcim coal fuel.

• Petroleum c oke analyses for the Holcim coke fuel

. • Analyses of the em issions from a dding recycled glass to the kiln.

• Chem ical an alyses of the sm elter slag used f o r iro n -substitu te in the k iln.
The EIS tea m concluded that the a ddition a l su bm ittals pro v ide adequ a te inf o rm ation f o r a f u ll EIS review. 

### 2.3 Dispersion M o deling Adequacy Review Com puterized air dispersion m odeling was used to estim a te the im pacts of the plant em issions on am bient concentration s of air contam inants. The adequacy review includes evaluation of the dispersion model selection, based on the criteria established in EPA’s Guideline on Air Quality Models. Th e choice a nd quality of m e teorological da ta was revie w ed to determ ine its applicability to the air qu ality im pact area. In their October 2001 s u bm ittal, Holcim used EPA’s Industrial Sou r ce C o m p lex (IS C3) m odel to model the changes in kiln em issions resulting fr om tire burning. During the next few years, EPA worked on estab lish i ng the AERMOD m odel as a p r eferred m odel for air qu ality perm it application modeling. In May 200 2, Holcim su bm itted revised kiln m odeling us ing the then

curren t vers ion of AERMOD. In February 2003, Hol c im subm itted addition al m odeling including the cem ent kiln dust (CK D ) handling source s a s well a s th e kiln in the AERMOD model. W h en EIS review began in January 2004, EPA had updated the AERMOD model and the version used by Holcim was no longer available (see www.e p a.gov/ttn/scram ) . As a result, DEQ requested that Holcim perform the additi onal m odeling using the most current AERMOD version. DEQ requested th at H o lcim m odel the total baseline em issions and the to ta l cum u lative em issions from the facility. Prev iou s HAPs m o deling had only included the increm ental change in em issions from tire burning. DEQ also requested that H o lcim extend the m odeling im pact grid beyond the orig inal 10 km radius around the pl ant. The addition a l m o deling request m a de it necessary for Holcim to update the modeling file s to the latest version of EPA’s recommende d model. Holcim provided the m odeling files in elect ronic form at so they could be duplicated and used as needed during the EIS review. Followi ng subm ission of the additional m odeling, the EIS team concluded that the modeling data is adequate for a com p lete E I S review.

5

## 3. Review of Emissions Inventory Methods Holcim estim a ted crite r i a pollutan t and HAPs em issions f r om the Trident kiln using a var i ety of m e thodologies. Kiln criteria pollutant em issions were obtained from s ource tests and existing perm it lim its. Estim ates of HAP em issions are m u ch harder to develop because the em issions are sm all, dif f i cult to tes t , and less d a ta is ava ila bl e. Holcim gathered a database of source tests from other cem ent kilns using tires as fuel and used the data to estim ate HAPs from the Triden t kiln.
The e m issions inventory review will include a review of the m e thodology used by Holcim to arriv e at th eir em issio n s estim ates. The HAPs e m issions estim ation m e thodology will b e reviewed in detail bec a u se of the u n certainty associated with HAPs em issions estim a tes. The assum p tions and calculations u s ed to accoun t for the effects of kiln u p sets on emissions are described in detail in Section 3.3. 

### 3.1 Emissions Estimation M e thodology Common methods of determ ining em issions from an existing or pr oposed facility or process are listed below

. Discussio n of the appropriateness of using each approach for criteria p o llutant and HAPs follows.

• Use of EPA em ission factors.

• Calculation of m a terial ba lance for a specific com pound.

• Use of source test data from si m ilar sources.

• Source tes t ing of an existing sou r ce or perm itted process.
• Continuous em issions monitoring system (CEM S). EPA has developed em ission factors for num e r ous industries and processes that produce air pollution. The e m ission factors are contained in EPA’s Compilation of Air Pollutant Em ission Factors, commonly referred to as AP-42. Th e Introduction to AP-42 discusses the relative reliability of the em issio n s estim ate m e thodologies lis ted abo v e (ref. 5). AP-42 Section 11.6 contains criteria pollutant em ission factors for portland cem ent kilns as well as tota l par ticu l ate m a tter (PM ) em ission f a ctors f o r var i ous m a terial handling operation s throughout the process. AP-42 also contains HAPs and air toxics em ission fa ctors for 26 particulate com pounds (including m e tals) and 44 gaseous compounds. The factors in AP-42 are appropriate for estim ating em ission from traditiona l fuels such as coal and natural gas but m a y not be appropriate for kilns us ing tire-derived fuel (TDF). The EPA AP-42 em is sion factors have been used for reference in establishing th e em issions inventory for the proposed project.
A m a teria l b a lance (o r m a ss ba la nce) approach may provide relia b l e average em issio n estim a tes for specific sources. In general, m a terial balanc es are app r o p riate for use in situ atio ns where a high percentage of m a terial is lost to the atm o s phere. Calcul ation of em issions through m a ss balance is frequently used for estim ation of SO 2 em ission, based on a num b er of sim p lifying assum p tions (ref. 5). Sulfur content of fuel is readily m easured, and SO 2 em issions are estim ated based on an assum p tion that all of th e sulf ur in the f u el is ox idized. Mass b a lance ca lcu l ations f o r

6trace contam inants such as gaseous and particul ate phas e HAPs are not feasible due to the sm all am ounts of t h ese contaminants in the fuel stream and the gas stream

. Holcim has used sourc e test da ta f r om sim ila r sources to develop an extensive database for em issions f r om cem ent kilns bu rnin g tires o r T D F. The datasets are shown in the em issions inventories in Appendix A and Appe ndix B. Holcim used the source test database prim arily for developm ent of HAP e m issions factors, but also used it as a referen ce source for criteria pollutant estim a tes. Holcim has perform e d source test s on the T r id ent cem ent kiln f o r criteria pollutants including CO, NO 2 , SO 2 and PM 10 . They are also operating contin uous em issions m onitoring system s (CEMS) for NO 2 and SO 2 . The source tests and CEMS provi de th e most reliable em issions inform ation, but are lim ited to the baseline case. Changes in criteria pollutant em issions due to tire burning have been estim at ed from other sources. 

### 3.2 Tire-burning Emissions Inventory Database Typically, em ission inventory developm ent relies heavily on AP-42 as the prim ary source of em ission fac t ors. As Holcim stated in the perm it application, AP-42 does not specifically address em issions f r om Portland cem ent kiln s using TDF in th e fuel m i x. Therefore, Holcim needed to obtain em ission factors for HAP s from TDF com bustion from other sources. T h e approach Holcim took to developing the TDF em ission fac t or s was similar to the approach used by EPA in developing the AP-42 em ission factors.
Holcim relied larg ely o n source tes t data f r om other sources to estim ate HAPs e m i ssions from the proposed project. In developing the em issi ons inventory for the cem ent kiln while burning tir es, Holc im com p iled sourc e test data from a num b er of cem e nt kilns. The sources had been tested while burning tires or TDF as part of the fuel stream . Many of the sources in the database also perform e d baseline testing without ti res during the sam e testing period. The source test database used for this analys is included 13 source tests from 11 kilns using tires or TDF for a portion of the fuel. The database includes both baseline te sts (withou t TDF) and cum u lative tests (with T D F). TDF use ranged from 7% to 33% of the fuel, on a heat basis. The baseline fuels used were coal, coal and coke, co al and oil, coal and waste oil, and coal and hazardous w a ste. The data set includ ed tests fro m seven dry process kilns and four wet process kilns. TDF was repor te d to be in the f o rm of ch ipped tires for six of the tests, w hole tires for four of the tests, and not specifi ed in the othe r te st r e por ts. A ccording to the pe rm it a pplica tion, the em issions inventory did not include any fac ility that exactly m a tched the T r iden t kiln’ s operating param e ters [long, wet kiln; coal/coke ba seline fuel; m i d-kiln introduction of whole tires; tires as 15 heat-percent of fuel m i x; electrostatic precipita tor (ESP ) em ission control] (ref. 1). Nonetheless, the em issions tes tin g data set co ntains a larg e num ber of sam p les and provides enough inform ation to ensure that a conserva tive em issions estim ate has been developed.
Holcim has developed the e m issions inventory for their tire-burning proposal in a manner sim ilar to that used by EPA to develop the AP-42 e m i ssion factors. W h en developing em ission factors for use in A P -42, EPA com p iled so urce test data from num e r ous source tests at Portland cem ent plants (ref. 7). EPA conve rted all the source test results to units of pound per ton of clinker. EPA

7used 71 stack tests, dated from 1971 to 1992 to develop the em i ssions factors in the curren t version of AP-42 Section 11.6. EP A rated the source tests based on available knowledge about the tests an d the sou r c e s. Af ter d i scard i ng te sts with lo w quality ra tings, EPA averaged th e rem a ining results to develop the AP-42 em ission factors.
Holcim took a m o re detailed approach to analyze th e tire-burning stack test data set, including all the tests with available data for each com pound. Data sets with m o r e than two data points allowed calculation of a n upper 95% confidence lim it (UCL) for the data set, which was used t o projec t em issions at T r ident. For d a ta se ts with less th an two data po ints, th e m a xim u m data point was used to project em issions at Trident. For data sets where the 95% UCL exceeded th e m a xi m u m data point, the m a xi m u m point wa s used to projec t em issions at Trid ent. More detailed inform ation about the m e thod used to process the source test data can be found in Holcim ’s perm it applica t ion (ref

. 1) and the m e mos in Appendices A and B.
Holcim used a m e thodology sim ilar to EPA’s for sta ndardizing the source test results. Instead of standardizing the test results based on clinker production Holc im standardized the source test results b a sed on fuel u s age. This is an appr op riate basis for com p aris on becaus e the p r im ary source of HAPs from the kiln is from fuel com b ustion, and Holcim was attem p ting to isolate the im pacts from changing the fuel m i x. Source testing has been perform e d on the Holcim Trid ent kiln f o r m o st of the criteria pollutants and som e of the HAP com pounds. The testing was perform e d with the kiln operating under curren tly pe rm itted con d itions with out us ing tir e s as f u el. Montana’ s a i r qu ality re gulations do not allow Holcim to conduct a test b u rn with tir e s until they obtain an air quality per m it allowing them to burn tires. Therefore, it is not possibl e to obtain s ource-sp ecif i c em ission test d a ta for the Trid ent kiln while b u rning tire s. Holcim has perform e d source tests on the Trid ent stack to m easure em issions of 13 HAPs, copper (a non-HAP) and dioxins/furans. Data from Holcim ’s site-specific stack tests has been used to verify the e m issions estim a tes obtaine d through the databas e . Holcim has subm itted a table com p aring s t ack test result s, d a tabas e pro j ected em ission ra tes and AP-42 em i ssion rates. The table an d a m e mo explain i ng th e da ta are contained in Appendix C.
Holcim ’s database pro j e c ted cum u lative em issio n s are all h i gher than the Trident source tes t data. The database values ar e close enough to the te st results to provid e confidence in the analysis, but are high enough to provide conserva tive estim ates of em issions. The database projected cum u lative em issions are com p arable to valu es calcu lated using AP-42 em ission factors. This com p arison provi des confidence that th e databa se-pro jected em ission rates for other HAPs are with in an acceptable range. 

### 3.3 Estimating Emissions from Kiln Upsets Holcim developed a m e thodology f o r estim ating pot ential HAP e m issions from tire com bustion during Trident kiln upsets. An upset is assum e d to cause th e ESP to be of f

- line and particula t e phase HAP em issions are assum e d to be uncontrolle d until the ESP is back online. The duration of an average upset was estim a ted based on the duration of upset events th at o ccu rred du rin g 2000 and 2001. The average duration of an upset was 13.2 m i nutes, but DEQ has recommended

8that the duration of an upset be set to 30 m i nutes in an hour for th e analysis of short term i m pacts from upsets (ref. 1)
The total annual duration of upset conditions was estim ated base d on the average of the hours of upsets that occurred during 2000 and 2001. T h e kiln experien ced 110 hours of upsets during 2000 and 53 hours of upsets during 2001, resulting in an average of 81.6 hours of upsets over the two-year period. The num b er and duration of up sets has been reduced since 2001, partially due to the use of a continuous opacity m o nito ring system (COMS) on the kiln stack.
Assum e d upset cond itio ns were us e d to dev e lop an ‘ups et m u ltip lie r’ for each HAP. The upse t multiplier for a 1-hour averaging period is d i ffere nt from the upset multiplier for the annu al averaging period. The upset m u l tiplier is applied to the m odeled i m pact to produce a conserva tive am bient concentr ation value f o r us e in the r i sk assessm ent. The upset multiplier s have not been applied to the em issions estim ates d i scussed later in this report. DEQ and Holcim have assum e d an ESP collecti on efficiency of 99.4%. W h en the ESP is not running, the particulate m a tter cont rol efficiency is assum e d to drop from 99.4% to 0%. ESP efficiency for particulate m a tter control is revi ewed in Section 4.4 of this report. Contro l efficiency for gaseous em issions (other than SO 2 ) is always 0% because the ESP does not contro l gaseous em issions.
Em ission rates provided in the em issions inventory are controlled em ission rates. The following equation is used to determ ine the uncontrolled kiln em ission rate for particulate m a tter. controlled rate = uncontrolled rate * (100% - 99.4%) uncontrolled rate = contro lled rate / (100% - 99.4%) uncontrolled rate = controlled rate * 166.67 The par ticu l ate m a tter h ourly ups et multiplier ( U M 1 ) to account for a 1⁄2 hour upset during the hour is calculated as follows: UM 1 = [controlled rate * 1⁄2 hr + uncon trolled rate * 1⁄2 hr] / (1 hr) = controlled rate * .5 + (controlled rate * 166.67 * .5) = controlled rate * 83.8 The particu l ate m a tter a nnual ups et multiplier (UM A ) to account for 81.6 hour s of upset during a year is calcu lated as follows: UM A = [controlled rate * (8760 hr – 81.6 hr) + uncontrolled rate * 81.6 hr] / (8760 hr)
= [controlled rate * 8678.4 hr + controlled rate * 166.67 * 81.6 hours] / (8760 hr) = controlled rate * 2.54 The particulate HAP em issions that are con t ro lled by the ESP include volatile m e tals, sem i

volatile m e tals, non-particulate m e tals, inorga nic com pounds and organic com pounds (ref. 1).
Volatile m e tals : Mercury An ESP upset only affects the particu l ate po rt ion of the volatile m e tal em ission s while th e gaseous portion of the volatile m e tal e m issions rem a ins the sam e . Mercury is assum e d to be 5%

9particula t e p h ase and 95 % gaseous phase when it re aches the ESP. The upset m u ltip lie rs f o r m e rcury are calcu lated as follows: UM 1 = gaseous em issions + particulate em issions * 83.8
= (95% * controlled em ission rate) + (5% * c ontrolled rate * 83.8) = 5.14 * controlled rate
UM A = gaseous em issions + particulate em issions * 2.54 = (95% * controlled rate) + (5% * controlled rate * 2.54) = 1.08 * controlled rate
Sem i -volatile m e tals : antim ony, lead, cadm i um , s e lenium and zinc (non-HAP) Non-volatile m e tals : chrom i um , arsenic, nickel, m a nganese Holcim assum e d the se mi-volatile and non-volatil e m e tals are 100% particulate m a tter and are controlled by the ESP. An ESP ups et will aff ect the to tal em issions of th ese m e tals, a nd the appropriate upset m u ltip lie rs ar e as f o llows: UM 1 = 100% * controlled rate * 83.8 UM A =100% * controlled rate * 2.54 Inorganic HAPs : hydrogen chloride, hydrogen fluoride Holcim assum e d 95% of the hydrogen chloride and hydrogen fluoride em i ssions are gaseous and 5% are p a rticulate m a tter. Therefore the upset multip liers for these com pounds will b e the sam e as for m e rcury. Organic HAPs : dioxin/furan (TCDD eq.) Holcim assum e d 80% of the dioxin/furan em issi o n s are gas e o u s phase and 20% are p a rticu l ate phase. Therefore, 20% of the dioxin/furan em issi ons are particulate phase and would be affected by an ESP upset. The u p set m u ltipliers f o r di oxin/f u ran are c a lculated a s f o llows:
UM 1 = gaseous em issions + particulate em issions * 83.8 = (80% * controlled rate) + (20% * controlled rate * 83.8)
= 17.6 * controlled rate UM A = gaseous em issions + particulate em issions * 2.54 = (80% * controlled rate) + (20% * controlled rate * 2.54) = 1.31 * controlled rate
The ESP does not control em issions of gaseous HAP s. Em i ssions of these HAPs are not affected by ESP upsets. The upset m u ltipliers for ga seous pollutants are equal to o n e (1.0).

10

## 4. Criteria Pollut a nt Emissions Inventory This se ction will evalua te the es tim ated cr ite ria p o llutant em issions chang e s re sulting f r om use of tires as fuel. Criteria po llutant em issions ar e regulated thro ugh Montan a’s air quality perm itting process. Maxim u m potential em issions from the Tr ident f acility while using tir e-d e rived f u el (ref. 1) are listed in Table 1.
TABLE 1 Potentia l Annual Kiln Criter ia Pollutant Emissions Pollutant Baseline Emission Rate tons/y ear Cum u lativ e Em ission Ra te tons/y ear SO 2 5 4 3 5 4 3 N O x 6 , 8 6 8 6 , 8 6 8 C O 1 2 1 3 1 0 PM 10 1 6 4 1 6 4 V O C 6 6 L e a d 0

. 1 5 0

. 1 5 Source: Hol c im, 2004 Fuel com bustion is the prim ary so urce of c r iteria polluta nts. CO is em itted as a r e sult of incom p lete com bustion of carbon in fuel. Combustion of tires as fuel in the kiln is expected to cause an increase in CO em issions. VOCs can be em itted as a result of unburned fuel or can be for m ed in the com bustion process.
Com bustion causes the form ation of NOx em issi ons due to oxidation of nitrogen in the com bustion air and in the fuel. VOC and NOx em issions are not expected to increas e as a result of tire burning. In fact, NOx has been show to decreas e significantly as a result of replacing a portion of the coal or co ke f u el with tir es. SO 2 is formed as a resu lt of the oxidation of sulfur in the f u el during the com bustion process. Because tires have lower sulfur content than coal, SO 2 em issions are exp ected to decrease when a portion of the fuel is replaced with tires. 

### 4.1 Carbon M onoxide Holcim has estim ated that kiln C O em issions will incr e a se signif i c a ntly as a r e sult of tir e burning. Holcim estim ates that addition of tires to the fuel mix would increase potential kiln CO em issions from 121 to 310 tons per year. During the perm it review pro cess, Holcim increase d the estim a ted CO e m issions beyond the value presen ted in the original perm it application. The Holcim perm it applica t ion sta t es : “ A nalysis of avai lable CO test data f r om other facilities show s that when com busting tires, som e facilities rea l ize an increase in CO em issions while som e facilities re a lize a dec r ea se in CO emissions. Ho wever, m o re recen t da ta from facilities with wet kilns ind i ca tes tha t tire c o m bustion m a y result in a significant increase in CO e m issions (ref. 1).”
Review of the literature and ava ilab l e sou r ce tes t data shows a m i x of results and interpretations on the CO em issions issue. The data shows that com bustion of TDF does not consistently lead to an increase in CO emissions, but com bustion of whole tires can cause an increase in C O

11em issions. Because Holcim is propo sing com bustion of whole tires, an es tim ated increase in CO em issions is appropriate. Holc im ’s baseline CO em ission rate for the Triden t kiln is 0.769 pounds per ton of clinker (lb/ton). The proposed allowable CO e m ission rate for the kiln is 1.461 lb/ton, which is equivalent to a concentration o f 200 parts per m illion (ppm ) in the stack gas

. The AP-42 CO e m ission factor for wet process cem ent kilns is 0.12 lb/ton, based on a single source test result (ref. 6). The AP -42 em ission factor has a rating of D, indicating that it is not a well-supported em ission factor.
The estim a ted increase of 189 tons per year exceeds th e Prevention of Significant D e terioration (PSD) significant increase level of 100 tpy. Ther efore, the proposed tire -burning project is subject to PSD requirem e nt for Be st Available Control Technology (B ACT) review. Holcim has subm itted a top-down CO BACT analysis to m e et the PSD r e quirem e nts

. DEQ has reviewed and approved the BACT ana l ysis. 

### 4.2 Sulfur Dioxide No increas e in sulfur d i o x ide em issio n s is pro j ec ted from the tire-burning pr oject. Studies have shown that sulfur oxide em issions are reduced as a result of burni ng tires in kilns (ref. 8). SO 2 em issions from ce m e nt kilns are generated fr om oxidation of sulfur com pounds in the raw m a terials an d f r om sulfur in the f u el. The a l k a line natu re of the ceme nt provides for direct absorption of SO 2 into the product, thereby m itigating the quantity of SO 2 em issions in th e exhaust stream . Depending on the process and the source of the sulfur, SO 2 absorption ranges from about 70 % to m o re than 95 % (ref. 6). Estim ated SO 2 contro l efficiency f o r Holcim ’ s Trident kiln is 87% (ref. 2).
The am ount of SO 2 generated in th e kiln is p r o portion a l to the SO 2 content of the fuel burned. Holcim has provided DEQ with sulf ur content infor m ation for their coal and petroleum coke fuel sources (ref. 11). According to the analys is attached to Ho lcim ’s air q u ality pre-construction perm it #0982-10, petroleum coke has a sulfur content of 5.3% by weight (ref. 2). Sulfur content of

the coal delive r ed to the Holcim plant is ge nerally less than 1% by we ight (ref. 11). Sulfur content of tires ranges from 1 to 3 pe rcent by weight (ref. 8). Holcim ’s SO 2 per m it lim it is 124 pounds per hour (lb / hr) and will no t change as a result of the proposed action. In the pe rm it applica tion (ref

. 1), Ho lc im provided a review of the poten tia l SO 2 em issions from a range of cem e nt kilns. Em issions were broke n down into categories, including dry kilns, wet kilns, kilns burning whole tires, kilns burning TDF with coal and cok e as baselin e fuels, and kilns burn i n g TDF with coal as the baseline fuel s. Overall, the kiln emissions sho w ed an 18% reduction in SO 2 em issions due to s ubstitu tion o f 10-20% of the f u el with tires. SO 2 em issions from dry kilns showed an increase of 20%, while SO 2 em issions from wet kilns showed a decrease of 32%. Us e of whole tires insert ed at m i d-kiln showed a 2% increase in SO 2 em issions, based on a very sm all number of test results (ref. 1). 

### 4.3 Nitrogen Oxides Substitu tion of tires and TDF f o r baseline f u els c ons isten tly c a uses a redu ction in NOx em ission s (ref

. 8). Total NOx em issions f o r all the tes t s in the database showed lower NOx e m issions on a production basis than the NOx allowed at Holcim. The data summ arized in the air quality perm it application shows that the NOx e m i ssions were reduced by 23% for all kilns, and were reduced

12in every category. The proposed perm it would lim it the allowable NOx em issions to 1350 lb/hr, on a 1-hour average basis. Holcim operates a NOx continuous em issions m onitor and reports the hourly readings to DEQ. 

### 4.4 Particulate M atter and ESP Efficiency Particula t e m a tter em issions f r om the Holc im k iln are con t rolled by a n ESP and will no t be affected by the tire-burning proposal. The ai r qua lity p e rm it lim its kiln p a rtic ulate m a tter em issions to 0.77 lb/ton clinker (ref. 2). The source test data set showed that the PM 10 em issions were reduced or unchanged by the use of tires for fuel (ref. 1). An evaluation of Holcim ’s ESP efficien cy is in cluded in the EIS review for two r easons. The review m u s t establish whether the particulat e control equipm ent at Holcim is generally com p arable to the con t rol equipm ent for sources in the em issions inventory database. This is im portant because it helps determ i n e whether the database is applicab le to the Trident kiln

. Second, the collection efficiency of the Trident k iln was evaluated to de term ine the validity of calcu lations inc l uded in the perm it applic ation m a terials. DEQ and Holcim have assum e d an ESP collection efficiency of 99.4% (ref. 1). T h is value w a s used to estim ate the am ount of particulate HAPs, pri m arily m e tals, present in the CKD.
Holcim provided the following description of the ESP used on the Trid en t kiln : Trident’s Electrostatic Precipitator is a Wheelabrator-Frye unit and was installed in 1972. The precipitator is one chamber wide and two fields deep in the direction of gas flow, creating two individual co llecting cells. Each individual collecting cell contains 79 collecting plates spaced 10” apart, creati ng 78 gas passages. Collecting plates that measure 30’ tall and 14.5’ wide, are formed by ni ne strip plates that are suspended from a common beam at the upper end and are s t a b iliz ed by a shock bar at th e lower end. These shock bars are individually struck by tumbling hammers during each cleaning cycle. Rig i d discharge electrode g r ids are su spended in each gas passage and are cleaned by a lift-and-drop hammer system. The elec trica l e n ergization for th is unit is supplied through two Westinghouse Transformer /rectifier sets. Both units are rated at: 1 phase, 60 hertz, 480 primary volts, 267 primary amps, 45 kV, 2000 mA (communication from Holcim)

. The electrostatic precipitation pro cess consists of three fundam e ntal steps: (1) particle charging, (2) pa rticle colle ction, a nd (3) rem o val of the c o llec t ed dus t f r om the collec tion p l a t es. Once a particle is charged, it migrates toward the collec tion surface. An indicator of particle m ovem e nt toward the c o llec tion e l e c trode is ca ll ed the particle m i gration velocity. Specific collecting area (SCA) is a param e ter used to com p are ESPs and roughly estim a te their collection efficiency. SCA is the total collecto r plate area divided by gas volum e flow rate (ref. 9). The Holcim ESP has two fields in series. Gas from the kiln passes through the first field where it is cleaned. Th e gas from the first field is further cleaned in the second field before exiting the stack.

13The total co llection area for each field in th e Holcim ESP is 67,860 square feet (ft 2 ), and the gas flow rate through the ESP is 170,265 actual cubic feet per minute (acfm ) . SCA for e ach field is equal to 398 ft 2 /1000 acfm. According to EPA’s ESP reference, an SCA of 400 ft 2 /1000 acfm is a m e dium SCA value. Therefore, o n e field of the Holcim ESP provides a m e dium SCA. Use of two fields in series increases the SCA to 800 ft 2 /1000 acfm , com p ared to a ‘large’ SCA value of 900 ft 2 /1000 acfm

. This SCA comparison indicates that the Holcim 2-fi eld ESP is a m e dium to high efficien cy ESP. The Handbook of Air Pollution Control Engineeri ng and T echnology (ref. 10) provides typical m i gration ve locities f o r v a rious ESP applic ation s
. The listed m i gration velo city f o r a wet proc ess cem ent kiln is 0.33 to 0.37 feet per second (fps). Efficiency of a precipitato r under ideal conditions can be estim a ted using th e Deutsch-Anderson Equation (ref. 10):
E = 1 – e (-w A/Q)
Where: E = collectio n effici ency of the precip itator A = the effective collecting plat e area of the pr ec ipitator (f t 2 ) Q = gas flow rate throu gh the pre c ipita tor ( acf s) e = base of natural logarithm = 2.718 w = m i gration velocity (ft/s) Based on the above equation, the efficiency of a si ngle field of the Holcim ESP woul d be greater than 99.9%. This calculation does not account for the variables including re-entrainm e nt and rapping. The use of two fields in series provides addition a l particu l ate rem oval. Based on this rough analysis, it is clear that the Holcim ESP efficiency is com p arable to other ESPs used in the cem ent industry. P a rticulate em i ssion control, including particulate m e tals, is expected to be equivalent to the particulate co ntrol a t the f acilities f r o m which the em ission estim ates were m a de. Holcim ’s assumption of 9 9.4% control efficiency for the ESP is found to be valid and appropriately conservative.

14

## 5. Hazardous and T o xic A i r Pollut a nt Emissions Inventory Com bustion sources can e m it trace am ounts of HAPs i n cluding organic com p ounds and hazardous m e tals compounds. The HAPs can either be a portion of the unburned fuel or raw m a terial, or can be generated during com bustion. Holcim ’s baseline and cum u lative em issions inventory identified and quantified HAPs that h a ve a po tential to in cre a s e as a result ofthe tireburning project. Methodology used to develop the em ission inventory was reviewed in Section 3 of this report. This section addresse s em issions estim ates for specific HAPs. The EIS team has recomm ended that DEQ adjust the allowable emissions increases in the Holcim perm it based o n review of the add i tio n al inform ation subm itted in suppo rt of the EIS. The original proposed perm it lim its were based on the estim ates of the increm ental increase in em issions from tire burning and did not reflect a com p arison of the baseline an d cum u lativ e em issions estim ates. The orig inal em ission es tim ates, and the bas e lin e and cum u lative em issions are sho w n in Table 2, Section 5.4. The baseline em issions inventory refers to the em issions from the cem ent kiln without tires as a fuel supplem ent. Baseline kiln fuels are coal and petroleum coke. The Trident kiln is pe rmitted to burn natura l gas, but Holcim has no plans to use natural gas fuel. Em issions of criteria and HAPs from natural gas would be lower than em issions from other fuels.
Baseline kiln em issions also includ e the em issions from ki ln feed. The prim ary k iln f e ed is lim estone from the Holcim quarry. There are no alte rnative s ources of calcium f

o r the kiln. Silica is need ed for the cem ent process and is m i ne d on-site. Holcimhas the option to use postconsum er recycled glass for the silica source in the kiln. Bas e line and cu mulative k i ln em issions include recy cled glass em issions . During the EIS review, it cam e to light that Holcim uses sm elter slag as a source of ir on in the cem ent raw m a terials m i x. No additional em issions or changed em issions have been identif ied as a result of slag use. 

### 5.1 Incremental HAPs Increase from Burning Tires The initial em issions inventory is reviewed here because it was used b y DEQ to establish th e allowable HAP em ission rates in th e draf t air qua lity perm it (ref. 2). T h e purpose of Holci m ’s original em ission inventory was to determ ine wo rst-case potential im pacts from the addition of tir es to the kiln f u el str eam . Holcim gathered em issions test data f r om cem ent kilns that used whole tires and TDF as part of th e f u el s t ream . Em issions d a ta we re contained in at least one of the tests for 165 different com pound s or groups of com pounds. Of the com pounds in the testing database, 65 were HAPs as defined in the list of HAPs identified in Section 112(b) of the federal Clean Air Act. Each pollu ta nt-spec i f i c p o tential incr ease was de term ined by identif y ing the em ission s tes t with the greatest increase between the with-tire and without-tire cases. If the test results showed that the with -tire case was higher than th e without-tire case, the d i fference was lis ted as p o sitiv e. If the test res u lts showed th at th e with-tire case was lower than the without-tire case, the difference was listed as negative.

15Holcim initially reported only the em ission rate change fo r each HAP but not the entire kiln em ission. Holcim tabulated the em issions differences for the source tests th at had data for both the baseline case and th e cum u lative case. They se lected the highest incr ease and reported it as the m a xim u m predicted inc r ease of tha t po lluta nt . This approach is highly conservative and m eets the needs of the air perm itting requir e m e nts. 

### 5.2 Expanded Emissions Inventory Holcim produced both a baseline em ission invent ory and a cum u lative em ission inventory using the entire da tabase. In this case, the data wa s not lim ited to source te st reports containing both baseline and cum u lative em issions for a particul ar pollutant. The baseline data for each HAP was evaluated to establish an appropriate baseline em ission factor. Likewise , the cum u lative (with tires) data f o r each HA P was evalu a ted to estab lish an app r opriate cu mulative emission factor. This approach resulted in a larger number of data points available for m a ny of the HAPs.
Holcim is p e rm itted to use r ecycled glas s as a k iln f eed and the glas s e m issions are inc l uded in the baseline and cum u lative inventories. None of the database source tests are known to include recycled glass. The glass was accounted for by adding the estim ated potentia1 em i ssions from glass to both inventories. W h en Holc im applied fo r the perm it to allow th e use of re cy cled g l ass, they com p leted a scr eening leve l r i sk assessm en t. Estim ated HAPs em issions r e sultin g f r om the glass were a s f o llows:
Chrom i um (total), uncontrolled: 9.6 lb/yr Chrom i um (total), controlled by ES P, 99.4% control: 0.0576 lb/yr Di-n-Butylphthalate: 0.272 lb/yr Butylbenzylphthalate: 0.053 lb/yr 

### 5.3 Recommended Adjustments in Emissions Inventory Em issions e s tim ates f o r som e of the pollu tants were adjusted based on the em issions inventory review. Each em issions inventor y change is discussed below

. Formaldehyde
Holcim use d the database to estim ate em issions of for m aldehyde from the kiln with and without tire fuels. Four stack test resu lts were availab l e for the baseline inventory and five stack tests were available for the cum u lative invento r y . The original increas e estim ate showed a for m aldehyde increase of 2.18 lb/hr or 9.55 tons per year (tpy). Com p ar ison of the baseline and cum u lative inventories, however, indicated a decrease in form alde hyde em issions of 4.74 lb/hr. This wide discrepancy in the form aldehyde em issions values triggered further review.
Exam ination of the database showed that the form aldehyde stack test results varied widely. Em issions from the four stack tests used to estim a te the baseline em issions were 7.36, 0.026, 1.23, and 0.21 lb/hr. The value of 7.36 lb/hr ap pears to be an outlier and is not consisten t with other data. Statistical evaluation of the baseline for m aldehyde em issions data with the outlier rem oved showed that the 95% UCL value would be 1.24 lb/hr.

16The data set for the cumulative em issions case ranged from 0.0054 lb/hr to 2.4 lb/hr, with a 95 % UCL value of 1.56 lb/hr. The estim ated increase due to burning tires is the difference between the cum u lative and baseline em i ssions estim ates, or 0.32 lb/hr. Dioxin/Furan Dioxin/furan lim its are expresse d as 2,3,7,8-tetrachlorodibenzo-p-di oxin equivalent (TCDD eq.). Table 2 includes dioxins/furans under the TCDD group heading. The TCDD eq. baseline value is based on Holcim' s 2000 stack test, correct ed from actual to m a xi m u m potential production using a ratio of the potential and actual production rates. The TCDD cumulative value assum e s a 60% increase for tires, based on review of data. Dioxin/furan e m issions estim ates are included in the em issions inventory but are not carried forward into the risk assessm ent. DEQ has de term ined that both the baseline and cum u lative risk assessm e nt analyses should be based on the PC-MACT regulatory di oxin/furan lim it. Dioxin and furan em issions are regulated under the P C -MACT rules. PC-MACT sets the dioxi n/furan em issions lim it for all fuels at 0.2 ng/dscm toxicity equivalent quotient (TEQ) fo r tem p eratures above 400 degrees F (ref. 12). Using the m a xi m u m kiln production and projected k iln f l ow rate, th e allowed d i oxin/f u ran em issions are 7.66 E-09 g/sec TEQ at Trident (ref. 1). Mercury Data used by Holcim to develop the highest pos sible inc r ea s e in em issio n s due to tir e burning yielded a high m e rcury em issions increase estim ate. The estim ated m a xi mum potential increas e in m e rcury as a result of burning tires was estim ated to be 1.02E-2 lb/hr or 89 lb/y r. Com p arison of the baseline and cumulative em ission invent ories sho w s a lower potential increas e. The com p arison is shown in Table 2. Using the database analysis, Holcim estim a ted that baseline m e rcury emissions would be 4.21E2 lb/hr (369 lb/yr). The cum u lative m e rcury em issi ons from the database were 1.42E-2 lb/hr (124 lb/year), a reduction of 245 lb/yr. T h is discrepancy in the em issions data indicated that further review of the m e rcury data was warranted.
The em issions database includes ten stack te sts for both baseline and cum u lative m e rcury em issions. The data set include s one test where the baseline m e rcury em issions were 1.31E-01 lb/hr, while the cum u la tive em issions were 6.9 9E-06 lb/h r. Both th es e value s a r e outsid e th e range of all other test data, and have been elim in ated from the analys is. The statistical analy s is has been repeated using only ni ne stack tes t re sults. The a d justed base line 95% U C L em ission rate is 1.16E-02 lb/hr (102 lb/yr) and the adjusted cum u lative 95% UCL e m ission rate is 1.57E

02 lb/h r (13 7 lb/y r). The m e rcury inc r ease from burn ing tir es is es tim ated to be 35 lb/y r, which is a 34% increase over the adjusted base line em ission rate of 102 lb/yr. The adjusted m e rcury increase of 34% is com p arab le to results found at other facilities. For exam ple, the ATSDR s t udy in Colorado (ref. 4) showed an increase of 29% m e r c ury while burning 19.2% tires. The EIS review has resulte d in a recomm endation that DEQ change the allowable mercury incr e a se in the pe rm it f r om the curr ent 89 lb/yr to 35 lb/yr.

17Manganese Holcim ’s original em issions increase estim ate for m a nganese was 7.9E-02 lb/hr. The m a nganese em issions in the baseline and cum u lative em issi ons inventories were 1.02E-02 lb/hr and 4.18E02 lb/hr res p ectiv ely. The difference between the baseline and cum u lative em issio n s rates was 3.16E-02 lb/hr, which is equivalent to 277 lb/yr. T h e EIS review has resulted in a recomm endation th at DEQ change the allowable m a nganese increase in the perm it from the current 691 lb/yr to 277 lb/yr. Other Compounds
The EIS review resulted in the f o llowing recommended e m ission inventory changes for com pounds that were present in one case but not the other.

• Acrolien, dim e thyl phthalate: recommend using the baseline value for the cum u lative value

• 4-nitrophenol: recommend using the cum u lative value for the baseline value 

### 5.4 Summary of HAPs Emission Estimates The scoping comments included questions about the d i fferences in em issions between cem ent kilns burning whole tires and TDF. The database used to estim ate HAPs em issions included both TDF and whole tires as fuel. No differences in the em issions were noted between the tw o fuel types. Questions were also raised abou t the em issions differences between wet process cem ent kilns and dry process cem ent kilns. Holcim has addressed the d i fferences in the perm it applic ation m a terials as they relate to cr ite ria p o llutants (ref. 1). No a pparent differences were noted in the HAPs e m issions databa s e between th e two kiln ty pes. Scoping comments indicated concerns about the ag e and condition of tires being bu rned in the kiln. In particular, there was a concern about tires containing pesticides, presum ably from the tire piles being sprayed to control mosquitoes. It is not possible to isolate every variable while burning tires for fuel in cem ent ki lns, but the breadth of the da tabase provides som e assurance that m o st va riab les a r e p r esent. The databa se of kiln em issions tes t s sp ans m o re than a dec a d e and includes tests from kilns in seve ral states. It is expecte d that a w i d e r a n g e o f t i r e a g e s a n d conditions were used in the source tests and any di fferences in e m issions are reflected in the test results.
All of the HAPs em issions estim ates have been com p iled in Table 2 for com p arison purposes. HAPs f o r which the so urce te st re s u lts were b e low the de tection lim it are exclud ed f r om the table. Changes in the em issions inventory fo r form aldehyde, m e rcury etc., as discussed above, are included in Table 2.
The colum n titled “or i g i nal” is Holcim ’s initial estim a te of the em issio n s inc r ease due to tire burning. The “baseline” and “cumulative” colum n s are the total kiln em issions. The values in the “d ifference” co lumn are calcu l ated by sub t ra cting the baseline value from the cum u lative value. A negative d i fference ind i cates that a decr ease in em issions of that pollu tant is predic ted.

18TABLE 2 Estimat e d Kiln HAP Emissions Compoun d O r i g i n a l Bas e l i n e Cumulativ e Differen c e l b / h r l b / h r l b / h r l b / h r Acetalde hyde

- 4

. 0 9 E

- 0 1 4. 77E-0 1 6

. 7 9 E

- 0 2

- 4

. 0 9 E

- 0 1 Acroli e n 1

. 1 2 E

- 0 2 1.12E-0 2 Trichloroethe n e 2

. 7 8 E

- 0 3 3. 72E-0 4 3

. 1 5 E

- 0 3 2.78E-0 3 A n t i m o n y 5

. 1 3 E

- 0 6 3.43E -0 4 3

. 4 8 E

- 0 4 5.13E-0 6 Arse n i c 7

. 1 5 E

- 0 5 5.79E-0 4 3

. 8 7 E

- 0 4

- 1

. 9 2 E

- 0 4 Benze n e 2

. 1 0 E

- 0 1 1.05E-0 0 8

. 6 2 E

- 0 1

- 1

. 9 2 E

- 0 1 Beryllium 8.17E-06 1.70E

- 0 4 1

. 2 8 E

- 0 4 -4.23E-05 Bis (2-ethylhe xyl)phthalate 1.17E -0 2 4

. 9 0 E

- 0 2 6

. 0 7 E

- 0 2 1.17E-0 2 Bromom etha ne (Methyl Bromide ) -1. 6 6 E

- 0 3 4

. 9 3 E

- 0 3 3. 27E-0 3

- 1

. 6 6 E

- 0 3 1,3 Butadien e/Butadiene -2.29E

- 0 3 3

. 5 4 E

- 0 3 9.11E-0 3 5.57E-0 3 2-Butan one (MEK) -7.08E-05 1.02E-0 3 9

. 4 9 E

- 0 4

- 7

. 1 6 E

- 0 5 Butylbenzylp h t h a l a t e * 6

. 0 5 E

- 0 5 6.05E-0 5 Cadmi u m 5

. 0 1 E

- 0 4 1.04E-0 3 4

. 0 2 E

- 0 4

- 6

. 3 6 E

- 0 4 Carbon Disulfide -1.12E-01 1.30E-0 1 1

. 8 3 E

- 0 2

- 1

. 1 2 E

- 0 1 Carbon T e tra c hlo r ide ND 3.82E-0 4 3.82E-0 4 Chlo r i n e 1

. 2 4 E

- 0 1 6.02E -0 1 7

. 2 5 E

- 0 1 1.24E-0 1 Chlo rob e n z e n e 6

. 5 6 E

- 0 4 7. 75E-0 3 7

. 8 5 E

- 0 3 1.02E-0 4 Chlo rom e tha ne (Methyl ch loride ) 5. 31E-0 3 4

. 9 7 E

- 0 2 2

. 06E-0 2

- 2

. 9 1 E

- 0 2 Chromium (to t al)* 1.09E-0 5 1.51E-0 3 1

. 1 4 E

- 0 3

- 3

. 6 7 E

- 0 4 Chromium 6 5.11E-0 5 2.76E -0 4 1

. 4 8 E

- 0 4

- 1

. 2 9 E

- 0 4 Cob a l t
- 3

. 9 4 E

- 0 4 8.47E -0 4 4

. 5 2 E

- 0 4

- 3

. 9 5 E

- 0 4 Di-n -Butyphth a late* 1

. 5 3 E

- 0 3 1.53E-0 3 1,4 Dichlorob enzene 8.57E-0 3 1.53E-0 3 1

. 0 1 E

- 0 2 8.55E-0 3 Dichlorometh a n e - 2

. 7 1 E

- 0 2 4.49E-0 2 3

. 1 0 E

- 0 1 2.65E-0 1 D i m e t h y l P h t h a l a t e 2

. 1 3 E

- 0 3 2.13E-0 3 2,4-Di nitro p h e n o l 1.15E -0 2 1

. 7 0 E

- 0 3

- 9

. 8 4 E

- 0 3 Ethylbenze n e 1

. 4 3 E

- 0 1 2. 22E-0 1 3

. 4 1 E

- 0 1 1.19E-0 1 Chlo roeth ane (ethyl chlo rid e ) 3.26E-0 3 ND Formal dehyd e 2

. 1 8 E

- 0 0 1. 24E-0 0 1

. 5 6 E

- 0 0 3.19E-0 1 Hydro gen chl o ride 5.98E-0 1 7.28E-0 1 7

. 6 6 E

- 0 1 3.82E-0 2 Hydro gen flu o ride 1.22E-0 2 2.24E-0 2 3

. 4 7 E

- 0 2 1.22E-0 2 L e a d 1

. 4 8 E

- 0 2 1.45E-0 2 1.47E-0 2 2

. 4 1 E

- 0 4 Manga ne s e 7

. 8 9 E

- 0 2 1.02E -0 2 4

. 1 8 E

- 0 2 3.16E-0 2 M e r c u r y 1

. 0 2 E

- 0 2 1.16E -0 2 1

. 5 6 E

- 0 2 4.05E-0 3 4-Methyl ph e nol -1.41E-03 6.46E-0 3 5

. 0 4 E

- 0 3

- 1

. 4 2 E

- 0 3 Methylene ch loride 2.26E-0 1 4.18E-0 2 2

. 0 2 E

- 0 1 1.60E-0 1 Nap h thalen e 1

. 8 5 E

- 0 2 6.53E -0 2 5

. 2 6 E

- 0 2

- 1

. 2 7 E

- 0 2 N i c k e l 1

. 8 4 E

- 0 3 1.79E -0 3 2

. 2 7 E

- 0 3 4.74E-0 4 Nitrob en zen e 1

. 1 3 E

- 0 4 1. 54E-0 3 1

. 6 6 E

- 0 3 1.12E-0 4 4-Nit r op henol N D 3.28E-0 2 P h e n o l

- 3

. 8 5 E

- 0 2 1.06E-0 1 6

. 7 6 E

- 0 2

- 3

. 8 6 E

- 0 2 Phosp h o r u s 9

. 0 5 E

- 0 4 3. 35E-0 3 4

. 2 6 E

- 0 3 9.08E-0 4 S e l e n i u m - 3

. 9 7 E

- 0 7 8.63E -0 3 5

. 3 7 E

- 0 3

- 3

. 2 6 E

- 0 3 S t y r e n e 2

. 6 8 E

- 0 1 2.71E-0 1 5

. 3 9 E

- 0 1 2.68E-0 1 1,1,1 Trichloroethan e 7.22E-0 4 1

. 8 4 E

- 0 4 1

. 4 6 E

- 0 3 1.27E-0 3 Toluen e 1

. 1 0 E

- 0 0 1.32E -0 0 2

. 0 0 E

- 0 0 6.78E-0 1 Vinyl chlori de 8.41E-0 3 1.07E-0 2 1

. 9 1 E

- 0 2 8.40E-0 3

19Compoun d O r i g i n a l Bas e l i n e Cumulativ e Differen c e l b / h r l b / h r l b / h r l b / h r Xylenes, total 7.50E-0 1 9. 78E-0 1 1

. 5 9 E

- 0 0 6.13E-0 1 Z i n c 1

. 4 3 E

- 0 2 5.45E-0 1 2

. 1 6 E

- 0 1

- 3

. 2 9 E

- 0 1 TCDD Eq. 2.41E-0 7 8.46E-1 0 1.35E-0 9 5.08E-1 0 Total PCBs 1.84E-0 4 4.43E -0 4 4

. 1 7 E

- 0 4

- 2

. 5 8 E

- 0 5 PAH- Total 1.89E-0 2 8.63E -0 2 6

. 4 1 E

- 0 2

- 2

. 2 3 E

- 0 2 PAH-Non -carcino geni c totals 2.79E -0 4 2

. 0 9 E

- 0 2 1

. 1 3 E

- 0 2

- 9

. 6 4 E

- 0 3 PAH-Carcin o geni c totals 1.87E-0 2 6

. 5 4 E

- 0 2 5

. 2 8 E

- 0 2

- 1

. 2 6 E

- 0 2 Note: ND indicat e s that the comp ound concentrati on w a s f ound to be lower than the detection limit of the test.

20

## 6.0 Air Dispersion Modeling Review Holcim has subm itted air dispersion modeling to pr edict the impacts of the proposed tire-bu r ning projec t on a m bient conc entra tions o f crite ria po llutants and HAPs. Holcim subm itted the f i na l modeling for tire com b ustion on May 10, 2004. The m odeling m e m o for the revised modeling is included in Appendix D. Holcim provided DEQ with electronic m odeling input and output files for use in the EIS review. 

### 6.1 AERM OD M o deling System Holcim ’s f i nal m odeling of the Tr ide n t plant wa s perform e d using EPA’s AERMOD model. The following is a brief description of the AERMOD m odeling system provided on EPA’s website: “The AERMOD is actually a m odeling system with three separate com ponents: AERMOD (AERMIC Dispersion Model), AERMAP (AER MOD Terrain Prep ro cessor), and AERMET (AERMOD Meteorological Preprocessor). AERMOD includes a treatm e nt of dispersion in the presenc e of interm ediate and com p lex te rra in that im proves on that curren tly in us e in ISCST and other m odels, yet without the complexity of the Com p lex Terrain Dispersion Model-Plus (CTDMPLUS). To the extent p r ac ticab le, the st ruc t ure of the inpu t or the con t r o l f ile f o r AERMOD i s the sam e as that for the ISCST3. At this time, the AERMOD contains the same algorithm s for building downwash as those found in the ISCST3 m odel. The AERMET is the m e teorological preprocessor for the AERMOD. Input data can com e from hourly cloud cover observations, surface m e teorologi cal observations and twice-a-da y upper air soundings. Output includes surface m e teorological obs ervations an d pa ram e ters and vertical profiles of several atm o spheric param e ters. The AERMAP is a te rrain p r ep rocesso r desi gned to simplify and standardize the input of terrai n data for the AERMOD. Input data include receptor terrain eleva tion da ta. The ter r a in data m a y be in the f o rm of digital te rra in da ta tha t is av ailab l e f r om the U.S. Geological Survey. Output includes, for each recep tor, location and height s cale, which are elevations used for the com putation of ai r flow around hills (see www.epa.gov/ttn/scram ) .”
Holcim perform ed the fi nal m odeling us ing AERMOD version 03273, AERMET Version 03273 and AERMAP version 03107. EPA sets the versi on num ber for each mode l version based on the year and Ju lian d a y of issue. Mon t ana DEQ ha s reviewed and approved Holcim ’s choice of models. DEQ and Holcim have agreed that a dditional revisions of the AERMOD modeling will not be required if EPA updates the AERM OD model during the EIS review process. 

### 6.2 AERM ET M eteorological Data Processing The AERM ET program creates the m e teorological input file for AERMOD using cloud cover data, surface m e teorological da ta and upper air data. National W eather Service (N WS) surface m e teorological data can be substituted for on-site data in th e even t th er e are no on
- s ite data to use. If the on-site profiles of wind or te m p erature are m i ssing, AERMET uses NW S data to create th e p r ofile of wind and/or temperature. No surface tem p er ature, wind direction or wind speed da ta were m i ssing f r om the Holcim data set. AERMET used th e Great Falls, Montana NW S surfac e data only for cloud cover values. Upper air observations are m a de by the NW S us ing radiosonde technology. The closest upper air station to the Trident site is at the Great Falls airport. The radiosonde is a sm all, expendable instrum e nt package that is suspended below a 6- foot (2-m eter) wide balloo n filled with hydrogen

21or helium

. As the radiosonde rises at about 1,000 feet/m inute (300 m e ters/m inute), sensors on the radiosonde m easure profiles of pr essure tem p erature and relative hum idity. These sensors are linked to a batte ry powered rad i o transm itter that sends th e sensor m easurem ents to a groun d receiver.
The AERM OD model requires hour ly surface m e teorological da ta param e ters. Holcim ’s m e teorological m onitoring station was located on the Holcim property 1228 feet (374 m e ters) southwest o f Holcim ’s cem ent kiln stack (ref. 1). DEQ has reviewed Holcim ’s meteoro l ogic a l station siting and data collection m e thods and has approved the m e teorological data set for use in com p liance modeling.
The m e teorological s e n s ors were lo cated at the sam e elevation as the k i ln exhaus t. Elevation at the Holcim m e teorological station was 4,132 feet above m ean sea level (ft m s l) and the height of the m e teorological tower was 33 ft ( 10 m e ters). Elevation of the wind speed and wind direction sensors was therefore 4,165 ft m s l. Elevation at the kiln stack base is 4,035 ft m s l, and the kiln stack height is 130 ft, res u lting in a kiln st ack exh a ust elevatio n of 4,165 ft m s l (ref. 1). Bluffs along the west bank of the Missouri River acro s s from the Holcim facility rise to elevations o f nearly 4,500 ft m s l. The hills eas t and southeast of the facility are also 4,500 ft or higher. W i nd patterns recorded at Holcim ’s meteoro l ogic a l stat ion show that this confining terrain causes the wind to follow the Missouri Rive r in a southwest-northeast orientation. Figure 1 is a wind rose showing the m onitored wind pa tterns at the Holcim location. The wind rose shows the frequency of winds from each of 16 cardin a l directions ( north, no rth-northeast, northeas t, etc.). The len g th of each “petal” indi cates th e frequency of winds blowin g from that direction. A s described in the legend, the bands in the petals indicate the frequency of the listed wind speeds.
The wind rose for the Holcim site shows a str ong southwest-northeast or ientation of the wind pattern, as would be expected due to the topogr aphy of the monitoring site. As shown in Figure 1, 25% of the hourly average w i nd directions were from the s outhwest and 13% of the hourly average wind directions were from the north-nor theast. The strongest (h ighest velocity) winds were from the north-northeast, as shown by the relativel y large dark section at the end of the north-northeast petal of the wind rose. The dark section indicates wind speeds greater than 10.8 m e ters per second (m /s) or 24 m iles per hour (m ph). 

### 6.3 Sources and M odeling Parameters The air dispersion m odeling protoc o l f o r the f i n a l m odeling is desc ribe d in deta il in Holcim ’s modeling mem o in Appendix D. Holcim m odeled th e kiln criteria pollutant and HAP e m issions

. They also modeled CKD f ugitive dust source s including silo load ing, silo unload i ng and the CKD monofill. The k i ln is a poin t source with a vertical stack and a b uoyant high -tem perature plum e. The CKD sources are fugitive dust sour ces released near groun d level and at am bient tem p erature. Em issions from the CKD sources have little m o m e ntum and do not im pact recep tors far beyond the plant bound ary. CKD em issions are particu l ate m a tter and m a y contain trac e am ounts of HAPs. Partiti oning of HAPs into the CKD was describ e d in detail in the perm it application m a terials (ref. 1). The partition i ng ca n be viewed in Section 6.4 of this report.

22F I G URE 1 Wi n d Rose f o r H o l c i m ’s T r i d en t Meteorol o gi cal Mon i tori n g S t ati o n

Sour c e : Lor enz en Engineer ing, Inc

. W i n d Ro se fo r H o lc im 's Tr id e n t M e te o r o l o g ic a l M o n i to r i n g Sta t io n A p r il 1, 2000 t h r o u g h M a r c h 31, 2001
N

S W E

N o observati ons w e re m i ssi ng. W i nd fl ow i s F R OM the di recti ons show n. R i ngs draw n at 5% i n terval s. C a l m s ex cl uded. 2.84 12.63

5.24

3.14

2.00

2.04

4.11

5.83 8.70 10.86

24.66 10.45 2.51

1.29 1.99 1.72

W i nd Speed ( M e ters Per Second) 0. 1 1. 54 3. 09 5. 14 8. 23 10. 8

23Downwash caused by influences of buildings on the kiln plum e were m odeled using EPA procedures and software. Downwash results from wake effects as the plum e encounters buildings and can result in higher pollutant c onc entra tions in the bu ilding wake. AE RMOD was run with EPA’s regulatory default options.
Com p liance with the ambient air q u ality stand a rds requires that sources evaluate the im pacts of other sources that could potentially affect the sam e area. Holcim ’s criteria po llutant com p liance dem onstration did not include m o deling of other s ources. As part of the EIS review, industrial sources loca ted with in 3 0 m iles (50 km ) of the Ho lcim plant have be en identified an d are listed in Table 3. EPA’s facility em issions web site (see ww w.epa.gov/air) was used to identify em issions sources in Gallatin County. Neighbor ing Madison and Broadwater Counties each have one industrial em ission source, both of which are located m o re than 50 km from the Holci m site. TABLE 3 Gallatin County Industrial Emissions Sources Facilit y Name Location T y pe of Sour ce Actual Emissions (1) Luzena c America Sappingto n Talc Proce s si ng Plant CO – 0.94 tp y NOx – 3.23 tpy VOC – 0.19 t p y SO 2 – 0.15 tpy PM 10 – 9.67 tpy Luzena c America Thre e Forks Talc Proce s si ng Plant CO – 4.3 tpy NOx – 10.5 tpy VOC – 0.52 t p y SO 2 – 0.24 tpy PM 10 – 32.2 tpy Montana Stat e Univ er sity Bozem an Central He ating Plant CO – 0.51 tp y NOx – 20.0 tpy VOC – 0.88 t p y SO 2 – 0.09 tpy PM 10 – 1.92 tpy JTL G r ou p Belgra de Portable Agg r egate Cru s hi ng an d Scre enin g Plant CO – 42.5 tp y NOx – 3.12 tpy VOC – 19.8 t p y SO 2 – 24.4 tpy PM 10 – 40.0 tpy (1) Rep o rted e m issions obtai ned from EPA’ s air data w e b site for the most recent avail a ble y e ar, 199 9. Table 3 lists actua l em issions repo rted to DEQ a nd ultim ately to EPA. EPA m a intain s em issions data for reference years to allow com p arison of source data. The most recen t year of data available from EPA is 1999.
The EIS review concluded that the r e is no ne ed to m odel the of f

- site sources be cause the i r em issions are not expected to m easurably im pact the Holcim peak im pact recep tors. Em issions from industrial em issions sources in Gallatin County are quite low and are not expected to im pact the sam e terrain as the Holcim e m issions. The pri m ary source of e m issions from talc process i ng and aggrega t e cru s hing is f ugitiv e p a rticula t e m a tte r. NOx and CO are genera ted from burning natural gas and/or diesel for heating. 

### 6.4 M o deling Receptors AERMOD uses receptors with lo cation and elev ation p r ogramm e d into the m o deling files. Location is denoted with Universal Transvers e Mercator (U TM) coordinates. UTM coordinates are oriented north/sou th and east/west with coo r dinates in units of m e t e rs. Modeling recepto rs are typ i cally placed in a grid pattern. Sm alle r grid spacin g provides more refined m odeling results, but requires a large am ount of com puter resources. U pon com p letion of initial m odeling, it is custom ary to add a refined receptor grid at very close spacing around highest im pact

24recep tors. Figures 2 and 3 are surface m a ps show ing the m o deling recep tor grids. Holcim used the f o llowin g m odeling grids in the i r f

i nal m odeling analys is:

• Property Boundary Receptors . Receptors located alon g the Holcim property boundary at a spacing of approxim a te ly 50 m e ters, shown in Figure 2.

• Fine Recep tor Grid . Receptors extend at least 2.5 km in all directions from the cem ent plant at a spacing of 100 m e ters, shown in Figure 2.

• 5-km Grid

. Receptors extend from the fine receptor grid o u t to a distance of 5 km from the plant at a spacing of 250 meters. Th e inner edge of the 5-km grid is visible on Figure 2.

• 10-km Grid . Recepto rs extend from the 5-km gr id ou t to a distance of 10 km from the plant at a spacing of 500 m e ters.
• Refined Grid . Receptors surroundin g the points of highest impact from the fine grid and boundary m odeling. Spacing of the refi ned grids is 50 m e ters. The largest refined grid is located northwest of the kiln location along the Missouri River bank. A s m aller refined grid is located on the nor theast plant boun dary. Refined recep tors can be seen in Figure 2.

• Expanded Grid . Holcim has provided an expa nded m odeling grid extending 33 km west, 39 km east, 50 km south and 32 km north of the plant. The expanded grid has a spacing of 2,500 m e ters and is show n on Figure 3. Figure 2 shows the terrain and r eceptors within approxim a tely 3 km of the cem ent kiln stack. Location of the kiln s t ack is indicated on the figure. The su rface m a p in Figure 2 was created using the receptor elevation data from the AERM OD input files. Figure 2 shows that there are no recep tors located within the Holcim property boundary. Figure 3 is a surface map of the entire expanded m odeling dom a in. Approxim a te locations of towns and the Holcim site ar e sho w n f o r ref e re nce. Elev ations for the surface m a p are the elevations u s ed in the A E RMOD modeling. Th e m odeling recep tor g r id has been overlain onto the surface m a p to show the extent o f the m odeling. During the EIS review, recep tors w e re added al ong the Madison, Jefferson and Gallatin Rivers upstream of Trident and along the Missouri Ri ver downstream of Trident. DEQ’s ris k assessm ent contractor u s ed the concentrations at the rive r re ceptors to c a lculate aqu a tic im pacts for the risk assessm ent. Results at various riv e r re cepto rs are shown on Figure 2-2 of the risk assessm ent report (ref. 3). 

### 6.5 Summary of M o deling Results Modeling re sults f o r

cr iteria pollu ta nt im pacts we re not changed by any of the findings of the EIS review. Holcim dem onstrated com p liance w ith a ll a m bient stan dards. Res u lts of th eir modeling are summarized in Appendix D. The EI S review did not result in changes to any criteria pollutant em ission rates or m odeling pa ram e ters . Therefore the criteria pollutan t modeling results are unchanged. Peak m odeled impact s of criteria pollutants occur at or near th e Holcim property boundary. Modeled im pacts dr op off with distance fr om the source, so com p liance only needs to be dem ons trat ed at the point of peak im pact.

25