UNITED STATES ENVIRONMENTAL PROTECTION AGENCY REGION I JOHN F. KENNEDY FEDERAL BUILDING BOSTON, MASSACHUSETTS 02203-0001



## SEP I 3 1995

Sarah R. Anderson Division ofLicensing and Enforcement Bureau ofAirQuality Depal1ment ofEnvironmental Protection Stale House Station No. 17 Augusta, ME 04333-0017

Re: Alternative NOx RACT for Dragon Products Company. Inc. in Thomaston, Maine

DearMs. Anderson:

Thank you for the opportunity 10 review the proposed alternative NOx RACT for Dragon Products Company. Inc

.. in Thomaston, M::line. The enclosure cont::lins Ollr detailed comments. Pleaseenter these comments into the public record. IfYOlI have any comments on the enclosed. please contact Steven Rapp ofmy staffat (617) 565-9024.

Sincerely,

David B. Conroy. Chief Ozone Programs OOice

Enclosure

cc: Bryce Sprolll, ME DE?

### Enclosure: EPA Comments on the Proposed Allemative NOx RAeT 

### for Dragon Products Company, in Thomaston, Maine

1. Process and Combustion Modifications: For miscellaneous and alternative RACT determinations, Chapter 138.3.1 requires acompany to submit an analysis ofvarious options for the reduction ofNOxto the atmosphere. Specifically, the regulations require that the company submit, "anexamination ofthe technical and economic feasibility ofavailable NOx control techniques forthe applicableNOx emitting eC]uipment for which alternative RAeT emission limits

are sought, including but not limited to

... i. Low NOx Burners, ii. Overfire air, iii. Flue Gas reburn, iv. Burners out ofservice, v. Use ofalternative fuels-, vi. Selective non-catalytic reduction, vii. selective catalytic reduction, and viii. Alternative operating scenarios."

However, theapplication and proposed license fi'om Dragon Products Company (Dragon) contain only alimited analysis ofselective non-catalytic reduction, selective catalytic reduction, and a number ofprocess and combustion modifications. It 

### is not cle'H to EPA why otherpotential NOx reducing technologies for cement kilns, such as 10w-NOx burners/staged combustion, have not beenincluded in Dragon's analysis. The applic(jtion and proposed license describe Dmgon's kiln

as having an average clinkerproduction of55 IOns per hour with acapacity heat input of approximately 263 MMBtu/hr. TheEPA's "Alternarive Contra! Techniques (ACT) Document-- NOx Emissions From Cement Manufacturing (EPA-45J/R-94-004; March 1994)," discusses lowNOx burners at indirect fired long wet kilns, with capacity of50 tons clinker perhour and 300 MJv1Btu/hr, as having acost effectiveness of$230 per ton ofNOxremoved. According 10 the proposed license, Dragon has already converted the kiln from n "semi-direct" 10 an indirect-coal firing combustion system Therefore, Dragon's RACT anC"llysis should include an analysis of technical and economic feasibility ofusing low-NOx burners/staged combustion at the Thomaston facility.

Also, given that the application also mentions acurrent feClsibility study for burning tires in the kiln, EPA suggests that Dragon's analysis include this as a potential NOx redllction technique. The ACT shows similarfacilities with mid-firing oftires as having acost effectiveness of$430 per IOn ofNOxremoved, Additionally, with the recent proposal ofthe Open Market Trading Rule for Ozone Smog Precursors (see 60 FR 39668, August 3, 1995), EPA is strongly encouraging States to consider discontinuing the issuance afsource-specilic vari<lIlces for f<lcilitles where discrete emission reductions are available and economically feClsible. Therefore, all future requests for compliance extensions and alternative emission limits, sllch as for Dragon, should include in their analysis ofcontrol options the potential use ofdiscrete emission reductions to 

### comply with the otherwise applicable emission standard (see 60 FR 3968S, section Ill.e.6 ofthe preamble). Since the RACT compliance deadline has (llremly passed, EPA believes that it is reasonable to re{]uire Dragon to submit the nnfllysis ofthese additional options within the next 90 days.2. RACfConclusion: The proposed license states that, "The only reasonably availablecontrol technologies forthe reduction ofNOx are process and combustion modifications." As discussed in comment#1, EPAdoes not agree that Dragon's RACT analysis is complete. Furthermore, the proposed license states that, "Dragon instituled many ofthese control technologies in advanceof the RAeT analysis

...which have resulted in NOx emissions 20% below the average for wet process kilns**an~** emissions reduced to 60% oftile facility's maximum potential-uncontrolled NOx emissions." EPA agrees that thecombined effect ofthese modifications will reduce fuel use at the facility and may indirectly reduceNOx. However, theRACT analysis should provide an estimate ofthe reduction in the actual NOx emission rate from a 1990baseline. RACT is generally considered areduction ofthe actual NOx emission rate ofa unit of 30

- 50% from 1990 levels.

3. Emission Standards/Order: The proposed license lists an interim NOx emission limitation of 800 Ibs/hr for any hour period, 335 Ibs/hrexpressed as a90 day rolling average, and 1467 TPY. Yet, it is unclear how these interim limits were derived. The interim emission limit should be based on the expecled reduction from the approved controls. However. it is unclear ifany reduction is being required from theunit since the control analysis seclion ofthe proposed license lists the maximum hourly emission rate as 732 Ibslhr, yet Maine is allowing Dragon ahourly NOx emission rate of800 Ibs/hr.

Additionally. the proposed licenseallows Dragon to propose a NOx emission limitation by May 31, 1997. However, it is unclearto EPA why the facility, already equipped with aNOx monitoring system, needs almost 2 years to perform adequate testing! monitoring and propose an emission limit. This delay in assigning an emission limit amounts to a 2 year RACT compliance dateextension. EPA does not agree that such an extension is warranted. EPA believes that it is technically and economically feasible for Dragon to perform the testing and propose a limit within four months oflhe issuanceofthe final license or, l'lfter Ihe dale ofinstallmion oflow-NOx burners, ifthey are shown to be feasible in the analysis discllssed in comlllent #I.

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