Boiler Major Source and Boiler Area 

Source Rules

Revisions to May 2012 Rule

Briefing for OMB Staff

October 25, 2012

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Overview

►Revisions to rules since May 2012 submittal to 

OMB

► Boiler Major Source rule

► Boiler Area Source rule

►Since the May 2012 submittal, we received new 

data and analyses from industry.

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Boiler Major Source Rule: May 2012 Rule

Issue Revision

1. Applicability Extended exemption for R&D units to include testing boilers for military vessels.

2. Subcategories 1. Added separate subcategory for fluidized bed units with fluidized bed heat exchanger 

(i.e., coal refuse units).

2. Redefined limited use units from <876 hours to <10% annual capacity factor.

3. Emission limits 1. Developed a single PM limit for coal units.

2. Developed a TSM limit for liquid fuel subcategories.

3. Changes to other emission limits based on new and corrected data.

4. Work practices -

tune-up requirement

1. Allow delay of inspections for certain situations .

tune-up requirement 2. Requirement to optimiz Requirement to optimize CO emission to manuf e CO emission to manuf. specs. to also be consistent with an . specs. to also be consistent with any 

NOx requirements.

3. Allow units with O2 trim system to conduct tune-up every 5 years. 

5. Averaging times 

definitions

1. Changes “30-day rolling average” from 30 operating days to 720 operating hours.

6. Energy 

assessment

1. Added a cap (not to exceed 160 hours) on on-site technical hours for large fuel use 

facilities.

2. Added limitation on scope of “energy use system”

3. Exempted facilities operating under an existing energy management program.

7. Startup & 

shutdown

1. Revised the definitions from based on operating load to based on starting and stopping 

supplying steam.

2. Required engaging control devices when coal or heavy oil is fired during startup or 

shutdown.

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Boiler Major Source Rule: Revisions to the May 2012 Rule

Issue Revision

1. Emission limits 1. CO limits for several subcategories revised to reflect a threshold level (130 

ppm@3% O2).

2. PM limits for new biomass units revised to reflect BTF (0.03 lb/MMBtu = NSPS).

3. CO CEMS limit for coal stokers revised (from 33 ppm to 340 ppm) based on new 

CEMS data.

2. Startup & shutdown 1. Revised the work practice to include firing of clean fuel (natural gas, propane, 

distillate oil, ULSD, fuel oil-soaked rags, kerosene, hydrogen, paper, cardboard, 

refinery gas, and LPG) during startup.

2. Added biomass and Gas 2 gases to requirement for engaging control devices 

when fired during startup or shutdown.

3. Compliance dates Compliance date for units in Gas 1 (natural gas/refinery gas), limited use, or has heat 

input capacity < 10 MMBtu/h and subject to the tune-up requirement remains 

March 21, 2014 (as in March 2011 final rule). 

4. Impacts Discussion Revised discussion to include incremental changes to impacts based on amendments.

1. HAP reductions increased by 4,000 tpy

2. HCl reduction increased by 4,600 tpy

3. Mercury reductions decreased by 0.96 tpy

4. PM reduction decreased by 18, 500 tpy

5. Metals reduction decreased by 260 tpy

6. SO2 reductions increased by 50, 100 tpy

7. Capital costs reduced by $1 billion.

8. Annual costs reduced by $0.13 billion.

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Emission Limits for Existing Major Source Boilers

Subcategory May 2012 Final Limits (lb/MMBtu unless noted) Current Final Limits, lb/MMBtu, unless noted

Hg, 

lb/TBtu

HCl PM CO, ppm

(CO CEMS-based)

D/F, 

ng/dscm

Hg, 

lb/TBtu

HCl PM CO, ppm

(CO CEMS-based)

D/F

Coal stoker 5.7

Solid 

fuel 

subcat

.

0.021

Solid 

fuel 

subcat.

0.039 160 (33 – 10 day) WP 5.7 

Solid 

fuel 

subcat.

0.022 

Solid 

fuel 

subcat.

0.040 160 (340 – 30 day) WP

Coal fluid. bed with Int. 

Heat Exchanger-new 

sub.

0.039 140 (150 – 30 day) WP 0.040 140 (150 – 30 day) WP

Coal fluid. bed 0.039 49 (230 – 30 day) WP 0.040 130 (230-30 day) WP

Coal PC 0.039 62 (320 – 30 day) WP 0.040 130 (320-30 day) WP

Biomass wet stoker 0.034 1,500

(720 - 30-day)

WP 0.037 1,500

(720 - 30-day)

WP

Biomass fuel cell 0.020 1,100 WP 0.020 1,100 WP

Biomass fluid. bed 0.11 470 (310 – 30 day) WP 0.11 470 (310 – 30 day) WP

0.18 770 (520 – 10 day) WP Biomass dutch oven 0.28 770 (520 – 10 day) WP

0.44 2,800 (900 – 30 

day)

WP Biomass susp./grate 0.44 2,800 (900–30 day) WP

Biomass suspension 0.051 2,400 (2,000 – 10 

day)

WP 0.051 2,400 (2,000 – 10 

day)

WP

Biomass dry stoker 0.32 460 WP 0.32 460 WP

Heavy liquid 0.49 0.0011 0.062 12

(31 – 10 day)

WP 2.0 0.0011 0.062 130 WP

Light liquid 0.49 0.0011 0.0079 6.0 (60 – 1 day) WP 2.0 0.0011 0.0079 130 WP

Gas 2 7.9 0.0017 0.0067 5.0 WP 7.9 0.0017 0.0067 130 WP

Non-cont. liquid 0.49 0.0011 0.27 32 WP 2.0 0.0011 0.27 130 WP

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Emission Limits for New Major Source Boilers

•Subcategory May 2012 Final Limits, lb/MMBtu unless noted Current Final Limits, lb/MMBtu, unless noted

Hg, lb/TBtu HCl PM CO, ppm

(CO CEMS-Based)

D/F Hg, lb/Tbtu HCl PM CO, ppm

(CO CEMS-Based)

D/F

Coal stoker 0.80

Solid fuel 

subcat.

0.021

Solid fuel 

subcat.

0.0017 19 (33 – 10 day) WP 0.80 

Solid fuel 

subcat.

0.022 

Solid fuel 

subcat.

0.0011 130

(340-30 day) 

WP

Coal fluid. bed with Int. 

Heat Exchanger

0.0017 140 (150 – 30 day) WP 0.0011 140 (150 – 30 day) WP

Coal fluid. bed 0.0017 25 (230 – 30 day) WP 0.0011 130 (230 – 30 day) WP

Coal PC 0.0017 60 (320 – 30 day) WP 0.0011 130 (320-30 day) WP

Biomass wet stoker 0.034 620

(390 - 30-day)

WP 0.030 620

(390 - 30-day)

WP

Biomass fuel cell 0.020 910 WP 0.020 910 WP

0.010 230 WP Biomass fluid. Bed 0.0098 230 (310-30 day) WP 0.010 230

(310 – 30 day)

WP Biomass fluid. Bed 0.0098 230 (310-30 day) WP

Biomass dutch oven 0.0031 330 (520 – 10 day) WP 0.0032 330 (520 – 10 day) WP

0.026 1,100 (900 – 30 

day)

WP Biomass susp./grate 0.026 1,100 (900 – 30 

day)

WP

Biomass suspension 0.051 2,400 (2,000 – 10 

day)

WP 0.030 2,400 (2,000 – 10 

day

WP

Biomass dry stoker 0.32 460 WP 0.030 460 WP

Heavy liquid 0.48 0.00044 0.013 12

(31 – 10 day)

WP 0.48 0.00044 0.013 130 WP

Light liquid 0.48 0.00044 0.0011 3.0 (60 – 1 day) WP 0.48 0.00044 0.0011 130 WP

New gas 2 7.9 0.0017 0.0067 5.0 WP 7.9 0.0017 0.0067 130 WP

New non-cont. liquid 0.48 0.00044 0.023 25 WP 0.48 0.00044 0.023 130 WP

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Boiler Area Source Rule: Revisions to the May 2012 Rule

Issue Revision

1. Existing dual-fuel fired boilers

Applicability

An existing dual-fuel fired boiler (i.e., commenced construction or 

reconstruction on or before June 4, 2010) meeting the definition of gas-fired 

boiler that meets the applicability requirements of subpart JJJJJJ after June 

4, 2010 due to a fuel switch from gaseous fuel to solid fossil fuel, biomass, or 

liquid fuel is considered to be an existing source as long as the boiler was 

designed to accommodate the alternate fuel.

2. Limited-use boilers The limited-use subcategory includes any boiler that burns any amount of 

solid or liquid fuels and has a federally enforceable average annual capacity 

Subcategory factor of no more than 10 percent.

Limited-use boilers are not subject to the emission limits, the energy 

assessment requirements, or the operating limits.

Limited-use boilers are required to complete a tune-up every 5 years.

3. Residential boilers

Definition

A boiler serving a single unit residence dwelling that has since been 

converted or subdivided into condominiums or apartments may also be 

considered a residential boiler.

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Boiler Area Source Rule: Revisions to the May 2012 Rule

Issue Revision

4. Temporary boilers

Definition

Any temporary boiler that replaces a temporary boiler at a location within 

the facility and performs the same or similar function will be included in 

calculating the consecutive time period unless there is a gap in operation of 

12 months or more.

A boiler is not a temporary boiler if the equipment is moved from one 

location to another within the facility but continues to perform the same or 

similar function and serve the same electricity, steam, and/or hot water 

system in an attempt to circumvent the residence time requirements of this 

definition.

5. Initial compliance demonstration

Timing for certain boilers

Existing boilers located at existing major sources of HAP that become area 

sources (e.g., limit their potential to emit by making a physical change or 

taking a permit limit) before the first substantive compliance date for the 

Major Source Boiler Rule must demonstrate compliance within 180 days of 

the later of March 21, 2014 or the effective date of becoming an area 

source.

New or reconstructed boilers at existing major sources that become area 

sources must demonstrate compliance within 180 days of the later of March 

21, 2011 or startup.

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Boiler Area Source Rule: Revisions to the May 2012 Rule

Issue Revision

Existing boilers that have not operated between the effective date of the 

rule and the source’s compliance date must:

• complete the initial emission limit compliance demonstration no later 

than 180 days after the re-start of the affected boiler

• complete the initial performance tune-up no later than 30 days after the 

re-start of the affected boiler

• complete the energy assessment no later than the compliance date 

specified in subpart JJJJJJ

6. Tune-up standards up standards Boilers that produce electricity for sale may delay inspections of the burner 

Continuous compliance timing and 

requirements for certain boilers

Boilers that produce electricity for sale may delay inspections of the burner 

and the system controlling the air-to-fuel ratio until the first outage, not to 

exceed 36 months from the previous inspection.

Optimization of CO emissions should be consistent with any NOX

requirements to which the boiler is subject.

7. PM emission limit

Applicability to certain new oil-fired 

boilers

New or reconstructed oil-fired boilers that combust only oil that contains no 

more than 0.50 weight percent sulfur or a mixture of 0.50 weight percent 

sulfur oil with other fuels not subject to a PM emission limit under subpart 

JJJJJJ and that do not use a post-combustion technology (except a wet 

scrubber) to reduce PM or SO2 emissions are not subject to the PM emission 

limit.

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Boiler Area Source Rule: Revisions to the May 2012 Rule

Issue Revision

8. Monitoring, installation, 

operation, and maintenance 

requirements

General clarifications:

• Data requirements and 10-day average calculation for CO CEMS

• Data requirements and 30-day average calculation for CPMS

• Data requirements and 6-minute average calculation for COMS

9. Initial notifications

Timing for existing boilers

Existing boilers have until January 20, 2014 to submit their initial 

notifications.

10. Notification of Compliance General clarifications:

Status (NOCS) • Timing

• Information and certifications that must be included

• Electronic submittal of test data, performance evaluation data, and 

NOCS

11. Definitions Revision of current definitions and addition of new definitions:

• To reflect changes discussed above

• For consistency with Major Source Boiler Rule

12. Tables Clarifications to Emission Limits table and Work Practice Standards, Emission 

Reduction Measures, and Management Practices table to reflect

requirements for boilers in new subcategories (e.g., seasonal boilers, limiteduse boilers, oil-fired boilers with heat input capacity =< than 5 MMBtu/hr, 

boilers with oxygen trim systems that maintain optimum air-to-fuel ratio).

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