1 

MEMORANDUM

TO: Brian Shrager & Jim Eddinger, U.S. Environmental Protection Agency, OAQPS

FROM: Eastern Research Group, Inc.

DATE: August 2012

SUBJECT:   Revised August 2012 Development of Baseline Emission Factors for Boilers and

Process Heaters at Commercial, Industrial, and Institutional Facilities

1.0 INTRODUCTION

This memorandum discusses the processes used to develop baseline emission factors for

boilers and process heaters based on data reported by industry in the 2008 Questionnaire for

Boilers, Process Heaters, Incinerators, and Other Combustion Units (ICR No. 2286.01, OMB

Control No. 2060‐0616, EPA Form No. 5900‐122), the 2009 Test Plan for Boilers and Process

Heaters (ICR No. 2286.03, OMB Control No. 2060‐0616, EPA Form No. 5900‐122), and

subsequent data submittals.  This memorandum discusses only the changes in the methodology

used to develop baseline emission factors for the December 23, 2011 proposed reconsiderations

of the NESHAP for Major Sources:  Industrial, Commercial, and Institutional Boilers and Process

Heaters (76 FR 80598) and the NESHAP for Area Sources:  Industrial, Commercial, and

Institutional Boilers (76 FR 80532).  The methods used to develop baseline emission factors for

these rule notices are discussed in another memorandum.1

This memorandum is organized as follows:

1.0 Introduction

2.0 Baseline Emission Factors for Major Sources

3.0 Baseline Emission Factors for Area Sources

4.0 References

Appendix A:  Baseline Emission Factors for Boilers and Process Heaters at Major Sources
2 

2.0 BASELINE EMISSION FACTORS FOR MAJOR SOURCES

There were no changes to the methodology used to estimate baseline emission factors

for major sources.  The methods used to estimate baseline emission factors for the December

23, 2011 proposed reconsideration of the rule (76 FR 80598) are described in another

memorandum.1 However, due to corrections to existing emissions data and the addition of new

emissions data, as well as a change to the way instrument calibration error is factored into

emissions data for carbon monoxide (CO), and the addition of one new subcategory, the

baseline emission factors have been recalculated using the same methodology.  A summary of

the emissions data corrections and additions received since the proposed reconsideration of the

rule is provided in another memorandum.2 The revised methodology for implementing

instrument calibration error for CO emissions data is also discussed in another memorandum.3

The revised baseline emission factors for major sources are provided in Appendix A.

2.1 New Subcategory

As a result of public comments received by EPA, a new subcategory was implemented

since the December 23, 2011 proposed reconsideration of the rule.  A separate subcategory has

been developed for Fluidized Bed units with an integrated heat exchanger (“FB‐HE”) designed to

combust coal or other fossil‐derived solid fuels.  Only one such unit is present in the major

source boiler and process heater inventory.  However, baseline emission factors for the

combustor‐based pollutants (THC, TEQ D/F, CO, formaldehyde, and NOx) were developed for

this subcategory.

2.2 Filling Data Gaps

Emissions data were not available for all pollutants for all subcategories.  As was done in

previous analyses, the data gaps were filled by defaulting to baseline emission factor averages

for another subcategory.  Appendix A contains notes describing where data gaps were filled by

defaulting to another subcategory.

2.3 Permanently Shutdown Units
3 

As discussed in the memorandum which provides the methods and procedures used to

estimate cost, emissions, and secondary impacts4

, five boilers in the heavy liquid subcategory

and one pulverized coal boiler were determined to be permanently shutdown late in the

regulatory process.  Due to time constraints, the data from these units were only excluded from

the calculation of MACT floor emission limits.  The methods and procedures used to calculate

the MACT floor emission limits are provided in another memorandum.5 The data for these units

are still incorporated into the cost, emissions, and secondary impacts estimates for the old

recommended option, and are also included in the calculation of baseline emission factors.  

3.0 BASELINE EMISSION FACTORS FOR AREA SOURCES

Although new baseline emission factors were calculated for major sources, no new

baseline emission factors were calculated for area sources.  The baseline emission factors

calculated for the December 23, 2011 proposed reconsideration of the rule (76 FR 80532) were

retained.  Area source emission limitations and the projected universe of affected sources did

not change from the proposed reconsideration of the rule.  As a result, cost and emission

impacts for area sources were not recalculated for the amended final rule.  Thus, a recalculation

of baseline emission factors for area sources was not necessary.  The methods used to develop

baseline emission factors for area sources are described in another memorandum.1

   
4 

4.0 REFERENCES

1. Eastern Research Group, Inc.  Revised November 2011 Development of Baseline Emission

Factors for Boilers and Process Heaters at Commercial, Industrial, and Institutional

Facilities.  November 2011.

2. Eastern Research Group, Inc.  Handling and Process of Corrections and New Data in the

EPA ICR Databases – Revised August 2012.  August 2012.

3. Eastern Research Group, Inc.  Incorporating Measurement Error in Reported Carbon

Monoxide (CO) and Total Hydrocarbon (THC) Data (Revised August 2012).  August 2012.

4. Eastern Research Group, Inc.  Revised (August 2012) Methodology for Estimating Cost

and Emissions Impacts for Industrial, Commercial, Institutional Boilers and Process

Heaters National Emission Standards for Hazardous Air Pollutants – Major Source.  

August 2012.

5. Eastern Research Group, Inc.  Revised MACT Floor Analysis (August 2012) for the

Industrial, Commercial, and Institutional Boilers and Process Heaters National Emission

Standards for Hazardous Air Pollutants – Major Source.  August 2012.

   
5 

APPENDIX A

Baseline Emission Factors for Boilers and Process Heaters at Major Sources