# Portland **Cement Reconsideration**

**Technical Support Document**



# DRAFT **May 31**  **20 12** ii **Table of Contents** 1. Introduction

................................ ................................ ................................ .......................... 1 2. O utdoor Clinker Storage Pile Work Practice Standard Development

................................ . 1 2.1 Control Measure Results

................................ ................................ ......................... 2 2.2 Emission Standard Results

................................ ................................ ...................... 3 3. Continuously

Monitored Parameters for Alternative Organic HAP Standard (with THC Monitoring Parameter)

................................ ................................ ................................ 4 4. Coal Mills

................................ ................................ ................................ ............................. 5 5. Allowing Sources With Dry Caustic Scrubbers to Comply With HCl Standard Using Performance Tests.

................................ ................................ ................................ ............. 10 6. PM Standard for Modified So urces Under the NSPS

................................ ........................ 11 7. Alternative PM L imit

................................ ................................ ................................ ......... 12 8. MACT Floor Development

................................ ................................ ................................ 12 8.1 Hydrogen Chloride (HCl)

................................ ................................ ..................... 13 8.2 Mercury

(Hg)

................................ ................................ ................................ ........ 14 8.3 Particulate Matter (PM)

................................ ................................ ........................ 15 8.4 Total Hydrocarbon (THC)

................................ ................................ .................... 15 8.5 Organic HAP (oHAP)

................................ ................................ ........................... 16 9. Impacts of Revised PM Standard

................................ ................................ ....................... 16 10. Summary

................................ ................................ ................................ ............................ 18

**List of Tables** Table 1: Summary

of 2012 Proposed NESHAP for Existing Sources

................................ ......... 13 Table 2: Summary

of 2012 Proposed NESHAP for New Sources

................................ ............... 131



### 1. **Introduction** In response to two separate events, the EPA is proposing amendments to the National Emission S tandards for Hazardous Air Pollutants (NESHAP) for the Portland cement industry (40 CFR part 63 subpart LLL) and to the New Source Performance Standards (NSPS) for Portland cement plants (40 CFR part 60 subpart F) issued under the Clean Air Act (CAA). In response to industry petitions for administrative reconsideration to reconsider the NESHAP standards and specific issues in the NESHAP, and to reconsider the NSPS PM standards , the EPA granted reconsideration of portions of the reconsideration petitions on May 17, 2011 (76 FR 28318). The issues in the NESHAP on which EPA granted reconsideration include: amendments to address the regulation of fugitive emissions from open clinker piles, organic hazardous air pollutant (HAP) compliance demonstration, applicab ility of standards to coal mills, requirements for monitoring h ydrochloric acid (HCl) when controlled using dry scrubbers, , the equations used to calculate the PM limits, the affirmative defense for malfunctions and specific issues relating to startup, shutdown and malfunction standards. EPA also granted reconsideration of the new source performance standards for particulate matter (PM) emissions from modified sources

. The proposed amendments also respond to the D.C. Circuit’s opinion in Portland Cement A ss’n v. EPA , 665 F. 3d 177 (D.C. Cir. 2011). In that case, the court rejected all challenges to the methodology

EPA used to establish the NESHAP but remanded the NESHAP so that EPA could account for the effects of EPA’s Non

- Hazardous Secondary Materials (NHSM) rule. EPA is proposing to amend the NESHAP new and existing source standards for PM , and to make corresponding amendments to the NSPS for PM. EPA is also proposing to amend the alternative organic HAP limit in the NESHAP, and to propose amendments regarding man y of the issues listed above. In addition, we are proposing corrections and clarifications to the rule’s testing and monitoring provisions

. Because the proposed changes in the PM limits could affect compliance strategies for some sources, EPA is proposing to extend the date for compliance with the existing source NESHAP to September 9, 2015, two years from the presently applicable compliance date. This Technical Support Document contains pertinent data, calculations, and discussion s regarding new emissions and work practice standards reflected in the proposal . For purposes of estimating cost and environmental impacts of the proposed amendments, the data used in estimating the impacts of the 2010 final rule were used with the exception that 24 kilns ( 14 facilities) burning commercial and industrial solid waste (CISWI kilns) were excluded. The modified data set consist of 11 6 existing kilns and 16 new kilns at 8 6 plants 

### 2. **Outdoor Clinker Storage Pile Work Practice Standard Development** The Portland Cement Association (PCA) has stated that most Title V permits contain provisions that redu c ed fugitive emissions from open clinker piles. To confirm this and to gather information on the ty

pes of measures required for outdoor storage piles, EPA reviewed 88 portland cement manufacturing facilities’ permits. Permits were first reviewed to confirm the existence of outdoor clinker storage piles and to identify the permit conditions addressing air emissions from these storage piles. EPA also examined these per mits for provisions regarding analogous ty

pes of piles, such as those for feed materials. Finall y, EPA reviewed permits to2

identify an y facility

- wide permit conditions relating to fugitive dust, visible emissions or opacity requirements. It was assumed that facility wide conditions apply

to any outdoor storage piles, unless the permit stated otherwise. For the purposes of this review, “control measures” were considered to be permit provisions requiring the facility

to implement some phy sical measure to control emissions relating to outdoor storage piles. Examples of control measures include:

 Requirements for:
o application of asphalt, oil, water, or other suitable chemicals o full or partial enclosure o wind barriers o moisture content o silt content o coverings o traff ic on and around storage pile(s) o earthen berm and biological wind break “Emission standards” were broken into three sub

- categories, as follows:

 General duty

requirements

– any

general requirement for the facility to “prevent” fugitive dust / particulate em issions.
o Example: The Permittee shall not cause, allow, or permit organic or inorganic dust producing material to be stacked, piled, or otherwise stored without taking reasonable precautions to prevent excessive amounts of particulate matter from becomin g airborne.

 Visible emissions limitation

– any requirement requiring the facility not to allow visible emissions or fugitive dust / particulate to leave the “facility property line.”
o Example: Emissions of fugitive dust from any transport, handling, constru ction or storage activity

at this facility

shall not be visible in the atmosphere beyond the property line of the facility

. o Example: The permittee shall maintain plant roads and grounds in the vicinity of the source permitted herein in the following manner so that dust will not leave the permittee ’ s property

 Opacity limitations

– any requirement specifying a numerical opacity limit not to be exceeded.
o Example: Opacity

of an emission from any

fugitive dust source shall not be greater than 40% measured in acc ordance with EPA Reference Method 9. **2.1 Control Measure Results**  The detailed results of the control measures review are presented in Appendix I . A summary of the results is presented below:

 Outdoor clinker storage piles

– 7 permits contained a specific control measure3

 Outdoor storage piles

– 16 permits contained a specific control measure
 Facility- wide permit conditions

– 31 permits contained a facility

- wide control measure

. **2.2 Emission Standard Results**  The detailed results of the emission standards review ar e presented in Appendix J . A summary of the results is presented below:

 Outdoor clinker storage piles

– 8 permits contained specific emission standards. The division of requirements is presented below: **Outdoor Clinker Storage Piles** General duty requireme nts Visible emissions limitation Opacity limitations

1 1 6

 Outdoor storage piles

– 18 permits contained specific emission standards. Please note that one facility had more than one type (example: general duty and opacity) of requirement. The division of requirements is presented below: **Outdoor Storage Piles** General duty requirements Visible emissions limitation Opacity limitations

6 2 12

 Facility- wide permit conditions

– 77 permits contained facility

- wide emission standards. Please note that many facil ities had more than one ty pe (example: general duty and opacity) of requirement. The division of requirements is presented below: **Facility**
**- wide Permit Conditions**  General duty requirements Visible emissions limitation Opacity limitations

27 31 59 Of the 88 permits reviewed in this analy sis, 87 had either a control measure or an emission standard (i.e., general duty requirement, visible emission limit, or opacity limit) relating to fugitive dust / particulate matter control from outdoor storage (assuming t hat facility

- wide conditions pertain to outdoor piles). The permit reviewed for o ne Ohio facility appeared to lack control measures or emissions standards

. It is important to note that the state of Ohio does have fugitive dust and opacity standards relati ng to fugitive emissions from storage piles (refer to rule 3745

- 17

- 07(B) and 3745

- 17

- 08(B)). However these standards onl y appl y to facilities located within certain designated areas of the state. For example, the other facility in Ohio evaluated under th is analy sis has portions of its operations located in an area required to implement these standards. In conclusion, it appears nearl y all facilities evaluated have some sort of standard relating to fugitive dust from storage piles. However, for general duty requirements it is difficult to determine the extent to which a facility has actually

complied with “preventative” measures.4

Additionally , facility

- wide requirements were generall y assumed to appl y t o any outdoor storage piles, unless stated otherwise. Facility

- wide requirements are required by state rules and regulations, which vary

state to state. Therefore, there is inherent uncertainty regarding the intent of each state regulation and if/how it would apply to storage piles. Although the degree to which an y of the work practices successfull y prevent fugitive emissions will vary , if applied properl y various sources report emission reductions of 75 to over 90 percent (Western Regional Air Partnership Fugitive Dust Handbook, September 7, 2006 ; USEPA, Te chnical Background Document on Control of Fugitive Dust at Cement Manufacturing Facilities, 1998 )

. These work practices have also been identified and are promoted by air pollution control agencies as effective fugitive dust control measures (Pima County D epartment of Environmental Quality , Dust Control Measures, http://www.deq.pima.gov/air/pdf/DustBrochures/Dust_Methods_Constr.PDF ; City of Albuquerque Environmental Health Department, Air Quality Division, Fugitive Dust Control, 12//05, http://www.cabq.gov/airquality /pdf/dustcontrolmethods.pdf ). 

### 3. **Continuously Monitored Parameters for Alternative Organic**  **HAP Standard (with**  **THC Monitoring Parameter)**  EPA is proposing a revisio n to the alternative organic HAP limit from the 2010 rule’s 9 ppm to 12 ppm based on the method detection capabilities for Method 320 and Method 18, the two methods appropriate for the compounds measured when determining compliance with the alternative org anic HAP limit. For the total organic HAP emissions data, we applied the following procedure for determining an RDL for methods used in measuring organic HAPs. We determined method detection capabilities for Method 320 and Method 18 as appropriate for the various compounds (e.g., Method 320 for aldehyd es, Method 18 for arenes). We believe that this approach is representative of procedures practiced by the better performing testing companies and laboratories using the reasonabl y applicable and sensitive anal yt ical procedures. We determined for each of the organic HAPs the expected method detection level for the respective method based on internal experience and method capabilities reported b y testing companies. With these reported values, we identified the re sulting mean of the method detection levels as the representative detection level (RDL) because it is characteristic of accepted source emissions measurement performance. The following table summarizes those findings.

**Pollutant Method used**  **RDL ppmv, as mea**  **sured RDL** 

**ppmv @7% O2 dry** Formaldehyde Method 320 0.15 0.23 Acetaldehyde “ 1.50 2.34 Benzene Method 18 (adsorbent tube) 0.04 0.08 Toluene “ 0.04 0.08 Styrene “ 0.04 0.08 Xylenes (m,p,o) “ 0.12 0.24 Napthalene “ 0.03 0.06 The second step in the pro cess is to calculate 3xRDLfor the sum or total of the organic HAPs to compare with the emissions limit in the final rule. This step is similar to calculation of a practical5

quantitation limit in other NESHAP including the 2010 final portland cement NESHAP . See 75 FR at 54984. We use the multiplication factor of 3 to reduce the imprecision of the anal yt ical method until the imprecision in the field sampling reflects the relative method precision as estimated by

the ASME ReMAP study . That study indicates th at such relative imprecision remains a constant 10 to 20 percent over the range of the method. For assessing a potential standard relative to measurement method capabilities, if 3xRDL were less than the candidate standard, we would conclude that the standard can be reliabl y measured. If, on the other hand, the value equal to 3xRDL were greater than the standard, we would conclude that the calculated standard could not be measured reliably (or, put another way , failed to account adequatel y for measurement v ariability) . Where such was the case, we increase the calculated standard level to the value equal to 3xRDL. This would result in a standard where the method would produce measurement accuracy

on the order of 10 to 20 percent , similar to other EPA test methods and the results found in the ASME ReMAP study

. We summed the RDL s adjusted for dilution and moisture as shown in the table above. We determined 3xRDLfor the sum of the adjusted pollutants to be 11.2 ppmv @ 7 percent O2, dry

. This value is greater than the final 9 ppmv @ 7 percent O2, dry , in the final rule. As a result, we are proposing to adjust the total organic HAP limit to 12 ppmv @ 7 percent O2, dry . At this level, we believe that currently available emissions testing procedures and technologies provide the measurement certainty sufficient for sources to reliably demonstrate compliance . Section 10.5 below contains additional information regarding derivation of the relevant RDL s. 

### 4. **Coal M**  **ills** Cement kilns burn coal as their main fuel, and mill the coal before firing it. From the standpoint of air emissions, these coal mills are sometimes physicall y distinct from the cement kiln, generating emissions solely attributable to the coal mill and emitting exhaust through a dedicated stack. However, some kilns are configured so that coal mill emissions are commingled with kiln exhaust and the emissions are discharged through the main kiln stack. Finally , there are some configurations whereb y kiln emissions are routed to the coal mill and discharged throu gh the coal mill stack. First, EPA has promulgated new source performance standards (40 CFR Part 60 subpart Y) for coal mills. See 74 FR 51952 (October 8, 2009). These standards appl y to coal mills, including coal mills at cement manufacturing facilities, which emit through a dedicated stack. These standards do not appl y to coal mills at cement facilities whose only heat source is kiln exhaust. See section 60.251 (definition of indirect thermal dryer). This leaves at least partially ambiguous the regulat ory

treatment of the situations where a kiln whose coal emissions are discharged through the main kiln stack, and the coal mill whose emissions which receives some exhaust from the cement kiln so that some portion of the coal mill exhaust reflect cement ki ln emissions. Because we did not address these issues in the 2010 final NESHAP for portland cement kilns, we granted reconsideration in order to do so. See 76 FR at 28326. A cement kiln which commingles emissions from its coal mill with all other emissio ns and discharges through kiln emission points would have to meet all of the NESHAP. In the case of PM, the additional flow from the coal mill would be accounted for in the equation used to determine an alternate PM limit from commingled flows. See secti on 7 below

.6

In the case of a coal mill which receives and discharges some of the cement kiln exhaust, the regulatory

concern is that this re

- routing of kiln exhaust not become a means of avoiding the NESHAP controls for cement kiln HAP. Our basic principl e for this situation would be that the kiln demonstrate that it is meeting all of the NESHAP standards for pollutants not regulated under the subpart Y coal mill standard, that is mercury , THC, and HCl. Because the subpart Y standards contain a PM standard predicated on use of fabric filter control technology , we do not believe it necessary to account for diverted PM emissions. We are proposing the following compliance mechanisms for the mercury , THC, and HCl standards in this situation. We are proposin g that the sum of the kiln emissions and diverted kiln emissions (i.e. the kiln exhaust diverted to the coal mill) must not exceed the subpart LLL NESHAP emission limits for each respective HAP or HAP surrogate. The proposed rule contains requirements to d ocument the contribution of the emissions diverted to the coal mill. With respect to THC and HCl, because coal may

be a source of these emissions, we are proposing that performance tests for THC and HCl be performed upstream of the coal mill. For mercury , tests would be required downstream to account for any mercury removal in the coal mill air pollution control device (APCD), and to avoid double counting emissions of mercury from mercury that becomes re

entrained in the coal which is then burned b y the ce ment kiln (which emissions are otherwise accounted for in the NESHAP). An analogous situation is when a cement kiln has an alkali by pass which receives and exhausts emissions from the kiln. We are proposing that these emissions be subject to the same pri nciple

– the total emissions of the kiln and alkali by pass must meet the subpart LLL NESHAP

– and would use the same monitoring procedures to document compliance. The one (slight) exception is PM. Because there is no independent PM standard for an alkali by pass (unlike the situation for coal mills, where subpart Y regulates PM emissions), the summed PM emissions from the kiln and alkali by pass would have to be equal to or less than the PM limit in the subpart LLL NESHAP. Tests for PM from the alkali by pass would be downstream of the alkali by pass APCD to account for those emission reduc tions.

**a .**  **Mercury.** Although mercury from the main stack is monitored using a CEMS, there is no need for such monitoring for the gas streams from the coal mill. The gas str eam to the coal mill is small in comparison to the kiln exhaust, operation of the coal mill is intermittent, and the cost of requiring additional CEMS for coal mills would be overl y burdensome. Instead, we are proposing that performance tests for mercury b e conducted at such a coal mill once per year, and, as explained above, that the tests be conducted downstream of the coal mill. The proposed amendments require performance tests for mercury to be conducted using either Methods 29 or 30B in Appendix A

- 8 to 40 CFR Part 60. These performance tests would be required annuall y until the tested mercury

levels are below the method detection limits for two consecutive years, after which tests may

be conducted every

30 months. If test results at any time exceed the method detection limit, annual performance testing would again be required until mercury levels are below the method detection limit for two consecutive ye ars. The results of the performance test would then be summed with the emissions from the kiln stack to determine compliance with7

the mercury

emissions limit. Since kiln stack emissions are measured continuously with a CEMS, the coal gas emissions would need to be normalized on both a CEMS and production basis (lb/MM ton clinker) in order to be summed wi th the kiln stack emissions. To do so, we are proposing that the flow rate to the coal mill be continuously monitored. Using the results of the annual performance test and the flow rate, the owner or operator would develop a mercury hourly mass emission rate for the coal mill. Using the hourly mass emissions rate and continuous flow rate, hourly

mercury emissions from the coal mill could be determined and summed with the mercury

emissions from the kiln to determine continuous compliance (the same approach would be applied to a kiln with an alkali by pass that exhausts to a separate stack): ((Qab×Cab)+(Qcm×Ccm)+(Qks×Cks))/P ≤ MACT L imit Where: Qab = Alkali by pass flow rate (volume/hr) Cab = Alkali by pass concentration (lb/dscf) Qcm = Coal mill flow rate (volume /hr) Ccm = Coal mill concentration (lb/dscf) Qks = Kiln stack flow rate (volume /hr) Cks = Kiln stack concentration (lb/dscf) P = Kiln production rate (million tons clinker/hr) MACT L imit = Limit for mercury ( 55 lb mercury

/MM tons clinker) Thus, if the normalized test results at the coal mill control device outlet shows mercury emissions of 10 lb/MM tons clinker, emissions from the kiln would have to be less than 45 lb/MM tons of clinker to be in compliance with the proposed mercury emissions limit. For kilns also equipped with an alkali by pass, the same procedure as that for the coal mill would apply . Where a portion of kiln gases are diverted to a coal mill and to an alkali by pass, emissions from the coal mill and alkali by pass would be test ed, normalized, and summed and with the mercury emissions from the kiln to determine compliance with the emissions limit. As stated above, the proposed amendments require performance tests for mercury to be conducted using either Methods 29 or 30B in Appendix A

- 8 to 40 CFR Part 60. A cost of a single test would be $22,800 per year per kiln and $45,600 if tests are done on the coal mill and alkali by pass . The number of sources with separate stacks that would have to be tested is not known. If it is assumed that one

- half of the 133 kilns (67 kilns) would require test on both the coal mill and alkali by

pass , total nationwide cost would be $ 3.1 million per year ( 45600 *67)

. The capital cost of a single flow meter would be $35,780 and $71,560 if installed on the coal mill and alkali b ypass stacks. Annualized cost for a single flow meter is $11,275 and $22,550 for two

. Nationwide, the capital cost of flow meters would be $ 4.8 million ( 71560 *67) with annualized cost of $ 1.5 million ( 22550 *67)

.8

**b. THC and HCl.**  Becau se THC and HCl are concentration

- based limits, the proposed compliance demonstration differs in certain details from the procedure described above for the production based limits for mercury . We are proposing that kiln stack emission limits (to be continu ously

monitored) be calculated taking into consideration the volumetric exhaust gas flow rates and concentrations of all applicable effluent streams (kiln stack, coal mill, and alkali by pass) for the kiln unit as follows: ((Qab×Cab)+(Qcm×Ccm)+(Qks×Cks)) /((Qab+ Qcm+Qks) ) ≤MACT Limit Where: Qab = Alkali by pass flow rate (volume/hr) Cab = Alkali by pass concentration (ppmvd) Qcm = Coal mill flow rate (volume /hr) Ccm = Coal mill concentration (ppmvd) Qks = Kiln stack flow rate (volume /hr) Cks = Kiln stack concentration (ppmvd) MACT L imit = Limit for THC or HCl (ppmvd) This equation requires all values to be at or corrected to 7 % ox ygen. In order to determine the flow rates and concentrations of THC and HCl in the coal mill and alkali by pass stream s, the source would need to test annually using the appropriate test method and would need to monitor the flow rate of the kiln stack with CEMS. For HCl, the performance test would be performed using Method 321 in Appendix A to 40 CFR Part 63. For measurement of THC, Method 25A in Appendix A

- 7 to 40 CFR Part 60 would be required. With these data, the concentration of THC and HCl that must be monitored in the CEMS in order to demonstrate compliance with the MACT limit under this proposal can be calculated by solving for Cks (kiln stack concentration) from the equation above, as shown: Cks ≤((MACT Limit×(Qab+Qcm+Qks))

- (Qab×Cab)

- (Qcm×Ccm))/Qks This equation is based on the following:

 The total allowable mass emissions of THC and HCl for the kiln unit can be determined with the sum of all flow rates (coal mill, alkali by pass, and kiln stack) and the applicable MACT limit (THC or HCl) concentration. This yields the total allowable mass emissions per unit of time for the kiln unit according to the MACT limits and the site specific flow rates for the coal mill, alkali by pass, and kiln stack.

 By testing the coal mill and alkali by pass streams for concentration and flow rate, the actual mass of THC and HCl emitted per unit of time can be determined.

 Subtracting the actual mass emissions of THC and HCl leaving the coal mill and alkali by pass from the total allowable mass emissions for the kiln unit determines the remainder of allowable mass emissions that can be emitted through the kiln stack.9

 With knowledge of the flow rate at the kiln stack (measured b y CEMS) and the allowable mass emissions (i.e. remainder) that can be emitted through the kiln stack, a site specific concentration can be determined. The equation above provides a simplified approach to determining this value. As an illustration of how the site specific limit would be calculated, w e have provided the following example for calculating a site specific THC emission limit. In this example, we assume a kiln stack, coal mill and alkali by pass with the following volumetric flow rates and THC concentrations:

**Effluent Stream**  **Flow Rate**

**(dscm/ hr)**  **THC**

**Concentration (ppmvd)**  **(@ 7%** O 2 **) Notes**  **MACT LIMIT**  **(ppmvd) (@ 7% O2)**  Alkali Bypass Qab 38,233 Cab 56 Determined through test 24 Coal Mill Qcm 57,349 Ccm 56 Determined through test Kiln Stack Qks 286,746 Cks TBD Flow rate monitored by CEMS

With the simplified equation provided above, the THC value that must not be exceeded in the kiln stack (verified with CEMS) is determined as follows:

Cks ≤((3024×(38,233+57,349+286,746))

- (38,233×56)

- (57,349×56))/286,746 Using the equation above, Cks is less th an or equal to 13.3 ppmvd @ 7% O2. This site specific value would be monitored by a CEMS in order to demonstrate compliance with the 24 ppmvd MACT limit for THC

. The proposal for THC and HCl is thus essentially the same as that for mercury (except that c oncentrations are involved rather than production

- normalized mass): the flow

- weighted averages of THC and HCl must be less than or equal to the subpart LLL NESHAP. The kiln stack emissions are measured b y a CEMS (for THC) or by other applicable means (for HCl). The flow

- weighted contributions from other sources (the alkali by pass and the kiln exhaust diverted to the coal mill) are assessed b y annual testing and applied continuously with flow being measured continuously

(explained further in the next paragraph). As noted above, the testing of the kiln exhaust diverted to the coal mill would be conducted upstream of the coal mill for THC and HCl so that only

the kiln exhaust contribution is assessed. To monitor compliance continuously, we are proposing that gas flow rate from the coal mill and alkali by pass be monitored continuously and that a parametric limit for gas flow be established during the annual performance test . This flow rate measured during the annual performance test would be the maximum flow rate allowed during the year. If a higher flow rate is observed, the owner/operator would have to retest THC and HCl to obtain a new flow

- weighted concentration10

which would be summed with the kiln main stack THC or HCl concentration to determine whether th e kiln is still in compliance. Because of this requirement, the owner/operator should perform their test at a flow rate that would cover the range of conditions expected. For HCl, the performance test would be performed using Method 321 in Appendix A to 40 CFR Part 63. For measurement of THC, Method 25A in Appendix A

- 7 to 40 CFR Part 60 would be required. Annual cost of a single test would be $20,000 per kiln for HCl and $8,000 for THC. Annual cost if test s are done on coal mill and alkali by pass stacks wou ld be $40,000 and $16,000 for HCl and THC, respectivel y. The number of kilns with separate stacks that would have to be tested is not known. If it is assumed that one

- half of the 133 kilns would require the test, total nationwide cost would be $ 2.7 million per year ( 4 0000*67) for HCl and $ 1.1 million per year ( 16 000*67) for THC.

**c. PM**  **.** As explained above, in the situation where a cement kiln diverts some exhaust to an integrated coal mill, the coal mill would have to meet the subpart Y standards, and the kiln would have to meet the subpart LLL NESHAP standard but would not have to account for the diverted exhaust in doing so. In all other situations, PM contribution from a coal mill (or from an alkali b ypass) would be accounted for via the equation discuss ed in section 7 below . If the alkali by pass discharges separately , it would have to sum its PM emissions with those from the main stack and the summed emissions would have to be less than or equal to the subpart LLL NESHAP standard for PM. 

### 5. **Allowing Source**  **s With Dry Caustic Scrubbers to**  **Comply With HCl**  **Standard Using Performance Tests .**  The September 2010 final rule allows sources equipped with wet scrubbers to comply with the HCl standard b y means of periodic performance tests rather than with continuous mo nitoring of HCl with a CEMS. Sources electing to compl y b y means of stack tests must establish continuously

monitored parameters including liquid flow rate, pressure and pH and are required to perform an initial compliance test using Method 321 and to test every 30 months thereafter. Industry commented that this compliance option should not be limited to wet scrubber equipped units, but should also be available for units equipped with dry caustic scrubbers, in part because some sources will be equipped with dry scrubbers (due to water shortages) and should have the same operating flexibilities as wet scrubber equipped kilns. A recent review of data from a vendor of acid gas controls using a standard hydrated lime and a high performance h ydrated lime at a US cement manufacturing plant, revealed that HCl removal from dry scrubbers on kilns ranged from 90 to 95 percent HCl removal, depending on lime injection rates (Lhoist North America, Cement Industry Experience, DSI for Acid Gas Control, October 5, 2011). The results also showed the plant could meet the 3 ppm HCl limit. EPA also evaluated HCl removal efficiency using dry sprayer absorber with a fabric filter as part of the electric utility

generating (EGU) MACT rulemaking. Removal efficiencies ranged from 95 p ercent to nearl y 100 percent with an average of about 99.8 percent (Hutson to Nizich, HCl control using SDA/FF, November 29, 2011). In addition, information from the National Lime Association (http://www.lime.org/uses_of_lime/environmental/flue_gas.asp) an d the Institute for Clean Air Companies (http://www.icac.com/i4a/pages/index.cfm?pageid=3401)report HCl emissions reductions using dry lime injection technology of 95 to 99 percent from coal

- fired11

boilers in the electric utility industry , from municipal wa ste
- to
- energy facilities and from other industries. In the secondary aluminum industry , reductions in HCl emissions greater than 99 percent have been achieved (National Lime Association, Flue Gas Desulfurization, http://www.lime.org/uses_of_lime/environmental/flue_gas.asp). Given these high reported removal efficiencies, we propose to extend the same option provided to kilns equipped with wet scrubbers to dry scrubber

- equipped kilns. EPA is proposing that dry scrubber

- equipped kilns have the same option a s kilns equipped with wet scrubbers for complying with the HCl limit by means of an initial and periodic stack test rather than continuous compliance monitoring with a CEMS. The proposed amendment would require that the lime injection rate used during the performance test demonstrating compliance with the HCl limit be recorded and then continuously monitored between performance tests to show that the injection rate remains at or above the rate used during the performance test. The number of sources that are likel y to select this alternative monitoring approach is not known and impacts were not estimated. EPA is also proposing additional alternatives for kilns that are equipped with a dry or wet scrubber. Where either wet or dry scrubbers are used, we are pro posing that an owner or operator would have the option of using sulfur dioxide (SO2) monitoring as a monitoring parameter. We are also proposing to reduce the frequency of stack testing for scrubber

- equipped kilns using SO2 monitors for parametric monitoring. Under this alternative, SO2 would serve as an indicator of a scrubber’s performance and not as a direct indicator of HCl emissions. Kilns equipped with dry or wet scrubbers that choose to use SO2 monitoring would need to conduct an initial performanc e test for HCl while monitoring SO2 to establish an SO2 level that would indicate compliance with the HCl limit. EPA is proposing that a performance test be conducted again in five years, at which time the SO2 parameter could be reset. As alternatives to the required HCl CEMS monitoring requirement, impacts were not estimated. 

### 6. **PM Standard**  **for Modified Sources Und**  **er the NSPS** Under the September 2010 final NESHAP, existing kilns are subject to the NESHAP PM limit. If the kiln undergoes modification, it would continue to be subject to the NESHAP PM limit, but would now be subject as well to the NSPS limit for new sources. EPA believes that it is more appropriate for modified kilns to meet the NESHAP PM limit for existing sources and is proposing that existing kilns that are subject to the NESHAP existing source emissions limit would continue to be subject to that limit and not to the more stringent limit for new sources under the NSPS. EPA examined the cost that a modified kiln would incur if they had to reduc e emissions to the NSPS level and the amount of PM reduction. For an existing kiln to go from complying with a 0.07 lb/ton clinker limit to the new source limit of 0.02 lb/ton clinker ( a reduction in long term average emissions of 0.01967 lb/ton), it was assumed that the reduction would be achieved b y changing out baghouse bags every ye ar rather than every 5 years. For a 1.2 million ton/y

r kiln, annual baghouse cost would increase b y $0.4 million/y r. The reduction in PM emissions for this example kiln wo uld be 12 tons/y r. Thus a kiln would realize a modest reduction in PM emissions at a cost of about $34,000 per ton of PM reduced (See Appendix G).12



### 7. **Alternative PM Limit**  Some kilns combine kiln exhaust gas with exhaust gas from other unit operations, such a s the clinker cooler. The September 2010 final rule sought to accommodate commingled flows from the kiln and clinker cooler by providing a site specific PM limit and an equation for calculating the limit. In its reconsideration petition, industry brought t o EPA’s attention, that other flows, such as coal mill exhausts and alkali by pass exhaust flows in addition to the exhaust gas flow from the clinker cooler can be commingled as well. Without an allowance for these additional flows, the site specific PM lim it is stricter than EPA intended (since the PM concentration will be divided by

a lower number in the implementing equation), and penalizes the energy

- saving practice of commingling these flows. Although the form of the equation is correct, the equation is not written to accommodate sources other than exhaust gases from the clinker cooler. EPA is, therefore, proposing the following revised equation corrected to includes exhaust gas flows for all sources that would potentially be combined into a single exhau st gas stream, including the kiln, alkali by

pass, coal mill and clinker cooler: PM alt = 0.006 x 1.65 x (Q k + Q c + Q ab + Q cm)/(7000) Where: PM alt is the alternative PM emission limit for commingled sources. 0.006 is the PM exhaust concentration (gr/dscf) equivalent to 0.070 lb per ton clinker where clinker cooler and kiln exhaust gas are not combined 1

. 1.65 is the conversion factor of lb feed per lb clinker Q k is the exhaust flow of the kiln (dscf/ton raw feed) Q c is the exhaust flow of the clinker cooler (dscf/ton raw feed). Q ab is the exhaust flow of the alkali bypass (dscf/ton raw feed). Q cm is the exhaust flow of the coal mill (dscf/ton raw feed). 7000 is the conversion factor for gr per lb. If exhaust gases for any of the sources contained in the equation are not commingled and are exhausted through a separate stack, their value in the equation would be zero. The alternative PM equation for new sources is identical to the existing source equation except the PM exhaust concentration used in the equation is 0.002 grams per dry standard cubic foot, which is equivalent to the new source PM limit of 0.020 lb/ton clinker. 

### 8. **MACT Floor Development** Applying the definition of solid waste developed in the NHSM rule, EPA has determined that 24 cement kilns in the database which EPA used to develop the 2010 final NESHAP are now identified as commercial incinerators. Even though applying the reclassified kiln designation for the 24 kilns would have resulted in slightly different existing source emission stan dards for

1 Note that this figure would change correspond ingly if the EPA were to amend the existing source PM standard. The same is true of the PM term in the new source equation.13

mercury , THC and PM, EPA is not proposing to amend the existing source standards for mercury and THC. The reasons for this decision are presented in the preamble to the proposed rule. EPA is proposing to revise the existing and new source PM stan dards. Also as described above in section 3, the limit for the alternative organic HAP limit (with parametric monitoring of THC) is being amended to reflect the limits of detection in the available measurement technology

. The derivation of the limit for th e alternative organic HAP is described in section 10.5 below. A summary

of the amended NESHAP for existing sources is presented in Table 1

. **Table 1**  **: Summary of 2012 Proposed NESHAP for Existing Sources**

**Pollutant Unit of Measure**  **201 0 Final**  **NESHAP 2012** 

**Proposed NESHAP**  Hydrogen Chloride ppmvd 3 3 Mercury lb/MM tons clinker 55 55 Particulate Matter lb/ ton clinker 0.04 0.07 Total Hydrocarbon ppmvd 24 24 Organic HAP ppmvd 9 12 With respect to new source standards, EPA does not bel ieve that any reclassification and reanal ys is is necessary

under the court’s opinion. New source floors can be based on the performance of “the best controlled similar source , ” as opposed to existing source floors which must reflect performance of sources “in the category or subcategory

. ” CAA section 112 (d) (3) and (d)(3)(A). The changes to the particulate matter (PM) and organic HAP (oHAP) standards are not related to removal of the 23 kilns identified as incinerators. These changes are discussed belo w in the applicable sections. A summary of the amended NESHAP for new sources is presented in Table 2.

**Table 2**  **: Summary of 2012 Proposed NESHAP for New Sources**

**Pollutant Unit of Measure**  **2010 Final NESHAP**  **2012**

**Proposed NESHAP**  Hydrogen Chloride ppmvd 3 3 Mercury lb/MM tons clinker 21 21 Particulate Matter lb/MM tons clinker 0.01 0.02 Total Hydrocarbon ppmvd 24 24 Organic HAP ppmvd 9 12

**8.1 Hydrogen Chloride (HCl)** 
**a. Existing Sources** 14

The 2012 proposed HCl NESHAP for existing sourc es was developed by removing an y kilns from the 2010 Final data set that were identified as commercial incinerators and adding in any new kilns that now fall into the NESHAP pool (top 12 %). The 2012 proposed HCl NESHAP for existing sources was developed with this new pool of kilns using the UPLmethod with pooled variance. As shown in Appendix A , the 2012 result of the UPL analy sis for existing sources is less than three times the representative method detection level. As was done in the 2010 Final, EPA is proposing to retain the current limit (3ppmvd) developed as three times the highest method detection level

. **b. New Sources**  As shown in Appendix B , the best performing kiln used to set the HCl NEHSAP for new sources in the 2010 Final was not identified as a commercial incinerator, so the same kiln was used for this analy sis. As such, there is no reason the new source standard would change. **8.2 Mercury (Hg)** 
**a .**  **Existing Sources** EPA calculated the 99 th confidence UPL for Hg after removing kilns from the 2010 f inal data set that were identified as commercial incinerators and replacing them with cement kilns to create the pool of best performing 12 % of sources. The UPL for existing sources was developed with this new pool of kilns using the UPL method with pool ed variance, corrected for temporal autocorrelation with intraquarry variability . This process was identical to that used in the 2010 final rule with the exception of the kilns in the pool data set. Appendix C contains the calculation s used to develop th e 2012 proposed Hg NESHAP for existing sources (58 lb/MM tons clinker)

. As discussed in the preamble to the proposed rule, EPA is not proposing to revise the mercury limit for existing sources . We are proposing , however, to adopt 55 lb/MM ton clinker as a beyond the floor standard. This is the level of the 2010 final standard. The only difference in cost between the floor level of 58 lb/MM ton clinker and the proposed standard of 55 lb/MM ton clinker is the incremental cost of removing slightly more merc ury . This is because the control equipment needed for mercury (an activated carbon injection [ACI ] sy stem) would not alter, would not need to be sized differentl y, and would need to perform on average, nearl y identically at either a 55 lb/MM tons clinker o r 58 lb/MM tons clinker level. That is, in planning compliance, kilns would calibrate to achieve an average performance of 34.1 lb/MM tons clinker for a standard of 58 lb/MM tons clinker, and 31.7 for a standard of 55 lb/MM tons clinker, which translates t o an additional reduction of 2.4 lb/MM tons of clinker per ye ar. This equates to an estimated 180 pounds of nationwide mercury emissions per year. To estimate the additional cost of going beyond the floor, we assumed that the rate of carbon injection would be increased to increase the mercury

removal rate. The additional cost would then be the increased usage of activated carbon. Under the 2010 rule, we based the cost of compliance in part on an activated carbon injection rate of 3 pounds per million ACFM. Cost for an ACI s ys tem were developed for the 2010 final rule using costs from the state of New Jersey and the OAQPS Cost Manual. See Docket items EPA

- HQ

- OAR

- 2002

- 0051

- 1891, 1872, 3398 and 3457 for background information and an explanation of cost estimate s. The mercury reduction of 2.4 lb/MM tons of clinker is a 7 percent reduction from the level needed for long term compliance and we initially considered15

that the amount of carbon injected might also only need to be increased by 7 percent, from 3 lb to 3.2 lb per million ACFM. However, to allow for variability of removal effectiveness, pollutant loading and other uncertainties, we estimated the additional cost using an injection rate of 4 lb/ million ACFM. To achieve this additional reduction, we estimate d an additional cost of approximately

$ 359 ,000 for the industry , to purchase additional carbon injection materials. This equates to a cost
- effectiveness of $ 2 ,000/lb of mercury reduction per ye ar (see Appendix P)

. **b .**  **New Sources** With respect to new sourc e standards, a s shown in Appendix D , a pplying this same method to the new sources would produce a slightly less stringent UPL (and we include this calculation for purposes of information)

. As discussed in preamble , EPA does not believe that any reclassifi cation and reanaly sis for new sources is necessary under the court’s opinion because new source floors can be based on the performance of “the best controlled similar source.” Therefore, EPA is proposing to retain the new source Hg NESHAP developed under the 2010 Final (21 lb/MM tons clinker). **8.3 Particulate Matter (PM)** 
**a. Existing Sources**  The 2012 proposed PM NESHAP for existing sources was developed by removing an y kilns from the 2010 final data set that were identified as commercial incinerators and adding in an y cement kilns that now fall into the NESHAP pool (top 12 %). The 2012 proposed PM NESHAP for existing sources was developed with this new pool of kilns using the UPLmethod with pooled variance. This process was identical to that used in the 2010 final with the exception of the kilns in the pool data set. Finally , in applying the UPLequation, EPA used m = 3 to be consistent with the proposed requirement to determine compliance using a three run Method 5 test rather than a 30 day

rolling average

. Appendix E contains the calculations used to develop the 2012 proposed PM NESHAP for existing sources ( 0.07 lb/MM tons clinker). **b. New Sources**  The best performing kiln used to set the PM NEHSAP for new sources in the 2010 Final was not identified as a comm ercial incinerator, so the same kiln was used for this analy sis. We are proposing a standard of 0.02 lb./MM tons clinker rather than the 2010 final rule level of 0.01 lb/MM tons clinker because a 3

- run test will be used to determine compliance rather than a 30

- day rolling average, the calculation of the UPL uses m = 3 rather than 30. Appendix F contains the calculations used to develop the 2012 proposed PM NESHAP for new sources (0.02 lb/MM tons clinker). **8.4 Total Hydrocarbon**  **(THC)**
**a. Existing Sources**  The THC data for the 2010 standard consist of CEMS data for 15 kilns. After removing the four CI SWIkilns, nine kilns remain. Thus, the MACT floor kilns consisted of 12 percent of these nine kilns, or two kilns. The top two kilns were Suwannee and Holcim. When CI SWIsources are removed from the database for the 2010 standards, the existing source floor for THC becomes16

more stringent from 24 parts per million by volume (ppmv) to 15 ppmv, and the new source standard would drop from 24 ppmv to 11 ppmv (see Appendix K). This change results from removing from the database a CISWIcement kiln (the Lehigh Union Bridge kiln) with the lowest daily

average performance but with more associated variability than the other kilns. However, notwithstanding this calculation, the EP A is not proposing to reduce the level of either the new source and or existing source THC standard. With respect to existing source standards, EPA does not believe th at the existing floor level ( 15 ppmv) would be technically appropriate. It omits the vari ability of the similar source with the best average performance for THC (the Union Bridge kiln), and so may not be fully representative of variability of best performing sources. If the variability of the Union Bridge kiln is included along with the variab ility of the two best performing cement kilns, and applied to the two best performing cement kilns’ performance, the floor would be 24 ppm, which EPA is proposing as a floor (see Appendix O)

. **b. New Sources**  The basis for the new source standard was explain ed in the 2010 final rule. See 75 FR at 54981. As a best controlled similar source, the new source standard can continue to be based on the performance of this kiln (the Lehigh Union Bridge kiln). See the preamble to the proposed rule for more discussio n of the proposed THC standards. **8.5 Organic HAP**  **(oHAP)**
**a. Existing and New Sources**  For the total o HAP emissions data, EPA applied the following procedure for determining a representative detection level (RDL) for test method s used in measuring oHAPs . EPA det ermined method detection capabilities for Method 320 and Method 18 as the most appropriate for the various compounds (e.g., Method 320 for aldehydes, Method 18 for arenes) emitted by kilns

. EPA determined for each of the o HAPs the expected method detection level for the respective method based on internal experience and method capabilities reported by testing companies. With these values, EPA identified the resulting mean of the method detection levels as the RDL because it is characteristic of accepted source emissions measurement performance. EPA summed the RDL s of each o HAP in the data set and adjusted for dilution and moisture , then multiplied by

three

. Appendix H contains the calculations used to develop the 2012 proposed oHAP NESHAP for existing and new sources (12 ppmvd). 

### 9. **Impacts of Revised PM Standard** For PM, EPA is proposing to change the limit for existing sources from 0.04 lb/ton clinker to 0.07 lb/ton clinker. The PM limit for new sources also would be changed to 0.02 lb/ton clinker from 0.01 lb/t on clinker. The standard would be measured on a 3

- run basis rather than on a 30

- day basis with a CEMS (see the final paragraph of this section) . The proposed changes in the PM standards, while not considered significant in absolute terms will result in a small increase in total nationwide emissions. As explained in the impacts anal ys is for the 2010 rule (see Docket item EPA

- HQ

- OAR

- 2002

- 0051

- 3438), emission reductions were estimated by comparing baseline emissions to the long

- term average emissions of the MACT floor kilns. The average17

emissions, rather than the emissions limit, must be used because to compl y with the limit all or most of the time, emissions need to be reduced to the average of the MACT floor kilns. Under the 2010 rule, the average PM emissi ons from the existing floor kilns was 0.02296 lb/ton clinker. Under the reconsideration, the average PM emissions of the existing floor kilns is 0.02655 lb/ton clinker (see Appendix E) . This is an increase of 0.00359 lb/ton clinker over the 2010 rule. The average emissions for new kilns did not change, so there would be no change in emissions from new kilns. In the 2010 rule, total clinker production from existing kilns was 75,355,116 tons per ye ar. With an increase in PM emissions under the proposed rule o f 0.00359 lb/ton clinker compared to the 2010 rule, nationwide emissions of PM would increase b y 135 tons per year (0.00359 x 75,355,116 /2000). These calculations are not so precise as to reliably predict to the third decimal point to the right of zero, so this difference should be viewed as suggesting a directional difference in the standards. **Kiln type 2010 rule**  **Proposed rule Increment**  Emissions limit (lb/ton clinker Existing 0.04 (30

- day average with a CEMS) 0.07

(3

- run stack test) NA
MACT average emissions for compliance (lb/ton clinker Existing 0.02296 0.02655 0.00359 2010 baseline emissions (tons/y r) 10,326 10,326 NA Nationwide emissions reduction (tons/y r) Total 9 , 489 9 , 3 54 135
Although the final measures that the industry will take to impl ement the final standards will be site specific and cannot be accuratel y estimated here, it is possible that the industry would now be able to use existing PM control devices with less extensive modification rather than planned under the 2010 standard or rather than replacing them. Compliance strategies for the other HAPs, all of which involve some element of PM control, also may be affected. Cost savings from these alternatives could be significant. For example, we have performed a case study from the data set used in the 2010 impacts anal ys is. In this case study , the 21 ESP

- equipped kilns no longer need to install membrane bags on a downstream polishing FF, and one FF retain s their standard fabric bags rather than replacing them with membrane bags. The difference in annual cost for PM control under th is case study and the more stringent 2010 scenario is $18.6 million in capital cost and annualized cost of $ 4.2 million (see Appendix M). EPA believes this case study is a reasonable ty

pe of bounding estimat e. Under this comparison, the annual cost of compliance will be $4. 2 million less than under the 2010 rule. Under this comparison, the additional cost of reducing PM emissions to the 2010 rule level would be approxi mately $3 1 ,000 per ton of PM ($4 .2 milli on/ 135 tons PM). Assuming that 1 percent of PM is HAP (Docket item EPA

- HQ

OAR

- 2002

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- 3438) , the cost effectiveness would be approximately $3,000,000 per ton of HAP

. Because there are several substantial issues associated with the use of PS 11 at low PM emissions concentrations and given the variable emissions characteristics expected from Portland cement kilns, the EPA is proposing to change the compliance basis for the PM standard from CEMS

- based to stack

- test based (preamble s ection III.D discusses th ese issues in detail )

. That18

is, the performance test requirement for this proposed rule would be a annual three test run compliance test with the EPA Method 5. Th e proposed rule would continue to require use of PM CEMS equipment but, as explained below, that equipment would be used for continuous parametric monitoring instead of for compliance with the numerical PM emissions limit. Because the same equipment would be used, the capital cost of the equipment for continuous parametric monitoring and CEMS are the same. However, because PS 11 requires at least 15 Method 5 test runs, equivalent to five tests, as part of the PS 11 calibration requirements, there will be a considerable savings when compared to the proposed single Method 5 performance test. At $15,000 per ye ar for a single Method 5 test, the proposed rule will cost $60,000 less for testing than would be required under the PS 11 requirements for five tests at a cost of $75,000 At a savings of $60,000 per kiln, nationwide savings for 133 new an d existing kilns, would be $7.98 million per year. 

### 10. **Summary** A summary

of the costs for the proposed amendments are summarized in Table 3.

**Table 3. Cost of Proposed Amendments Proposed Amendment**  **Capital Cost Annualized Cost**  **Emissions Reduction**  Coal mill te sting and monitoring (section 4) Mercury THC HCl Flow meter Total $ 4,794,520 $ 4,794,520 $ 3,055,200

$ 1,072,000 $ 2,680,000 $ 1,510,850 $ 8,318,050 0 Mercury beyond the floor (section 7.2 ) 0 $359,000 180 lb Revised PM standard (section 8 ) $18,64 0,106 (savings) $4,200,000

(savings) 135 tons (emissions

increase) Replace PM CEMS with PM CPMS (section 8 ) 0 $7,980,000 (savings) 0 Total $ 13,845,586 (savings) $ 3,503,000 135 tons (emissions increase)

.