E Providing Environmental Technical Support Since 1989 C

/R Incorporated

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MEMORANDUM 

TO: Jaime Pagán, EPA OAQPS/SPPD/ESG 

 Melanie King, EPA OAQPS/SPPD/ESG 

FROM: Bradley Nelson, EC/R, Inc. 

DATE: June 12, 2009 

SUBJECT: Summary of the May 29, 2009 Meeting in Washington, DC with the Interstate 

Natural Gas Association of America and the U.S. Environmental Protection 

Agency to discuss the Proposed NESHAP for Existing Stationary RICE 

1.0 INTRODUCTION 

A meeting between members of the Interstate Natural Gas Association of America 

(INGAA) and the U.S. Environmental Protection Agency was held in Washington DC on May 

29, 2009. The purpose of this meeting was to discuss the proposed national emission standards 

for hazardous air pollutants (NESHAP) for existing stationary reciprocating internal combustion 

engines (RICE). The proposed NESHAP for existing stationary RICE was published in the 

Federal Register on March 5, 2009 (74 FR 9698). 

2.0 ATTENDEES 

U.S. Environmental Protection Agency

Bob Wayland, OAQPS/SPPD/ESG 

Melanie King, OAQPS/SPPD/ESG (by phone) 

Michael Horowitz, OAR/OGC (by phone) 

Larry Sorrels, OAQPS/HEID/ABCG (by phone) 

Interstate Natural Gas Association of America

Jim McCarthy, Innovative Environmental Solutions, Inc. 

Vincent Brindley, El Paso Corp. 

Charles Wait, Panhandle Energy. 

Mary Beth Whitfield, Williams Gas Pipeline 

Kasey Gabbard, NiSource 

Dan Regan, INGAA 

Lisa Beal, INGAA 
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EC/R Incorporated

Bradley Nelson (by phone) 

3.0 SUMMARY OF MEETING 

INGAA requested this meeting with EPA to discuss its comments on the proposed rule. 

INGAA is a trade organization that represents interstate natural gas transmission pipeline 

companies operating in the U.S. INGAA’s members transport over 95 percent of the nation's 

natural gas through a network of 200,000 miles of pipelines. This meeting summary will be 

available in the docket for this rulemaking (Docket ID No. EPA-HQ-OAR-2008-0708). 

Lisa Beal welcomed everyone to the meeting and stated that the purpose of the meeting 

was to discuss some issues and concerns with the proposed rule and to provide suggested 

revisions to address these issues. Lisa then turned the meeting over to Jim McCarthy who 

conducted the meeting using the presentation provided in Attachment A of this meeting 

summary. 

Emission Standards – MACT Floor 

 The first topic of discussion was the maximum achievable control technology (MACT) 

floor emission standards in the proposed rule. INGAA noted that its comments were focused on 

spark ignition (SI) engines and the proposed requirements for these engines. INGAA’s main 

comments on the MACT floor include: 

• lean burn engines being miscategorized as rich burn engines, 

• the use of CARB 430 to quantify formaldehyde emissions, 

• tests conducted at high loads only, and 

• test points listed as multiple source tests. 

Taking these points into consideration, INGAA stated the MACT floors are based on 

only zero to three valid tests. INGAA believes that additional test data is needed to develop the 

MACT floors for the SI engines. 

EPA stated that it had limited engine test data and have requested additional test data 

from other industry groups by October 2009. EPA is on a strict schedule to finalize the rule 

because it is under a court ordered deadline. If INGAA intends to provide additional test data, 

EPA asked that INGAA note in its comments on the proposed rule what test data will be 

provided and when EPA can expect to receive the test data. EPA also stated that it would prefer 

to receive full test reports, but will consider other forms of test data. EPA also asked INGAA if 

there were test data during startup, shutdown, and malfunction (SSM) operating periods of the 

engine. INGAA responded that test data may be available; however it will probably not be in the 

form of test reports. 

Above-the-Floor 
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 The second item that was discussed was the above-the-floor options in the proposed rule. 

INGAA stated that the hazardous air pollutant (HAP) emission factors and control costs are not 

consistent with the original RICE MACT, and therefore the cost effectiveness values are underestimated. In addition, INGAA noted that the control costs in the proposed rule do not take into 

account the type of engine or use. EPA requested that INGAA provide cost data to support its 

comments and to provide details on suggested revisions. EPA also stated that it would meet with 

INGAA after the comment period to discuss INGAA’s comments in more detail. 

Cost Effectiveness Values and Threshold 

 The third item of discussion involved the cost effectiveness threshold that was used to 

develop the above-the-floor options. INGAA presented what it believed was EPA’s rationale for 

selecting above-the-floor options for natural gas-fired engines. INGAA concluded that EPA 

used a cost threshold to determine the sizes of engines that would need to add control 

technology. EPA responded that the above-the-floor options are not based solely on technology 

or cost thresholds, but also on population, emission reductions, and other factors. EPA asked for 

specific comments on this issue. 

Startup, Shutdown, and Malfunction 

 The next item that was discussed was the SSM limits in the proposed rule. INGAA 

believes there are no data that supports these limits and asked how compliance will be 

determined for these limits. INGAA believes that work practices as defined in section 112(h) of 

the Clean Air Act (CAA) or generally available control technology (GACT) should be used. 

EPA asked for information on events, time required to get engine in standard mode, and what 

pollutants are emitted during these events. 

Compliance Implications 

 The next item that was discussed was the compliance implications of the proposed rule. 

INGAA stated that two stroke lean burn (2SLB) engines may not have a high enough exhaust 

temperature to use a catalyst. INGAA also pointed out that air compressors that cycle on and off 

may also not provide enough heat to make a catalyst effective in reducing exhaust emissions. 

EPA responded that this was a common comment and indicated that it is hoping to get additional 

data to look at other options. 

Major and Area Source Alternatives 

 INGAA recommended that GACT work practices be used in place of emission limits for 

rural area source engines and asked if EPA needed additional information to determine if GACT 

was applicable. EPA responded that it would review any rationale and data for using GACT in 

the comments and address the issue as appropriate. INGAA asked if EPA had looked at the unit 

risk estimate (URE) for engines located in rural areas. EPA responded that a study is in progress 

that looks at the URE and believes that the URE will be more stringent than the proposed 

standards. INGAA asked if urban/rural segregation of natural gas-fired engines was an option. 
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EPA responded that it would look into the issues that were brought forward by the comments and 

discuss them internally. 

Subcategories 

 INGAA asked what is needed to substantiate a subcategory in the proposed rule. EPA 

responded that subcategories are developed by class/type/size and that it would need additional 

data to develop new or additional subcategories. EPA asked for what engines was INGAA 

proposing to subcategorize. INGAA stated that the recommendations for subcategories would 

depend on the revised MACT floor. INGAA asked how EPA would classify an engine used as 

an air compressor. EPA replied that an air compressor would be classified as an intermittent 

process type. 

Management Practices 

 INGAA supports the application of management practices rather than using MACT 

limits. INGAA believes that the operator designed practices under the New Source Performance 

Standards (NSPS) would harmonize the operator requirements. EPA stated it will look to see 

what management practices are appropriate and indicated that it is aware of the frequency 

limitations in the proposed rule. However, the management practices that are selected must be 

structured and enforceable, EPA stated. 

Test Methods and Compliance Monitoring 

 INGAA commented about the viability of Method 323 to measure formaldehyde from 

natural gas-fired engines. INGAA noted that there have been some concerns noted by EPA 

Region 8 and INGAA that should be documented in the docket. Without an alternative, fourier 

transform infrared spectroscopy is the only option from measuring formaldehyde from rich burn 

engines. INGAA also noted that the pressure monitoring provisions in the proposed rule are 

unclear and that requiring pressure monitoring for remote engines will be difficult because there 

is no electricity in those areas. 

Reporting and Recordkeeping 

 INGAA stated that the reporting and recordkeeping requirements in the proposed rule do 

not minimize the burden on the owner/operators of the engines. INGAA asked that the 

recordkeeping and reporting requirement provisions that were included in the SI NSPS be used. 

EPA asked for specifics on what requirements should be revised in the comments submitted by 

INGAA. 
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Rule and Implementation Complexity 

 INGAA noted that this was the fifth significant engine rulemaking in the past 5 years and 

that this particular rulemaking affected many more units including, commercial, residential, and 

industrial source types. EPA responded that the proposed rule addresses recent court decisions 

and that EPA is required to set numerical limits for all categories at major sources. INGAA 

stated that the EPA did not account for operating variability when assessing the MACT floor. 

EPA responded that it can only use the top 12 percent to look at variability. If more data was 

received EPA could look at variability options. EPA stated that it did not want to send section 

114 letters to obtain data, but wanted to receive information from the industry. 

Plans/Next Steps 

 EPA asked INGAA to prioritize its list of issues before sending its comments on the 

proposed rule. 
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Attachment A 

INGAA Presentation 
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IC Engine NESHAP: 

Proposed Revisions 

to Subpart ZZZZ

INGAA – EPA Meeting

Washington, DC

May 29, 2009

Topics (1) 

z Basis for the Emission Standards

» MACT Floor analysis – Emissions data

– Variability and operating condition impacts

» “Above the Floor” analysis – Cost effectiveness data

» SSM emission limits – Data and basis for conclusions

» Catalyst required for all engines with emission limit

» Compliance certification issues

– Standards apply “at all times” including SSM events

» Concern: Docket data and analysis do not support 

these requirements

» Alternatives for some engines or operating conditions: 

– Area source – GACT 

– Major source – Clean Air Act §112(h)
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Topics (2)

z Urban versus rural IC engine requirements

» Exemption or GACT work practice alternatives

» Implication of formaldehyde URE review

z Subcategories

» Basis for defining subcategories

z Management Practices – Basis and frequency

z Test Methods and Compliance Monitoring

z Reporting and Recordkeeping (Part 63, Subpart A)

» Reconciliation with other recent IC engine rules

z Integration and EPA intent from recent Court cases

z Addressing data gaps for natural gas-fired ICEs

» Timing for data development & EPA analysis

» Deferred rule schedule for natural gas-fired engines?

Emission Standards: MACT Floor

z INGAA reviewed the Emissions Database data points and 

INGAA Comments will identify significant issues

» Many formaldehyde tests based on CARB 430 

» Engines miscategorized or test condition is atypical

– e.g., Rich Burn with exhaust oxygen >>2%

» Multiple test points on one engine should not be considered 

multiple “sources”

– Data may be pertinent for variability, offload emissions, etc.

» Size-specific emissions should be reviewed

» For the three natural gas-fired engine subcategories, INGAA 

review concludes 0 to 3 tests available for the MACT Floor

» Conclusion: Additional data is needed

z Consideration of emissions variability, operational effects 

(e.g., load, application, etc.) is not evident in the docket
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Above the Floor

z Cost analysis apparently based on single vendor quote 

from ~5 years ago

» Communications do not discuss specifications – e.g., 

vendor guarantee and operational limitations

» Costs and HAP emission factors are NOT consistent with 

2002 docket memos from the original RICE MACT

– Higher costs; Above the Floor standard was not warranted

» Costs are NOT consistent with operator experience

» INGAA comment: Cost effectiveness values ($ per ton) 

are significantly under-estimated

z Data gap – Collect additional data on control costs and 

peripheral costs (e.g., testing, recordkeeping)

» 90% control assumption is not supported 

z INGAA conclusion: Actual cost per ton is much higher 

and above the floor controls are not justified

Above the Floor

Cost Effectiveness Values and Threshold

z Controls were proposed for some subcategories

» These decisions appear to define the cost threshold for 

above the floor controls for natural gas-fired engines

» Table from docket document number OAR-2008-0708-0117

z For natural gas-fired engine subcategories in shaded 

cells, above the floor controls were not required

z INGAA concludes that this indicates the cost threshold

» $3,660 – $5,040 per ton for Lean Burn ($~3,600 at 250 hp)

» $13,000 – $33,000 per ton for Rich Burn ($~20,000 at 50 hp)

Size Range (HP) Engine <50 50 – 100 100 – 175 175 – 300 300 – 500 500 – 600 600 – 750 >750 

2SLB 

(Ox Cat) $19,887 $7,798 $5,039 $3,658 $2,887 $2,578 $2,425 $2,207 

4SLB 

(Ox Cat) $19,887 $7,798 $5,039 $3,658 $2,887 $2,578 $2,425 $2,207 

4SRB 

(NSCR) $33,373 $13,162 $8,549 $6,241 $4,952 $4,435 $4,180 $3,815 
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Startup, Shutdown & Malfunction

z SSM limits added in response to December Court decision

z Communication with EMA appears to be only support 

documentation

z Data is not available to support SSM Emission Limits

» Limits based on the MACT floor (“best performing’) are not 

consistent with understanding of engine emissions 

combustion chemistry

– HC and CO emissions higher at reduced load, cold start, etc.

z Basis for compliance is undefined – e.g., “instantaneous” 

measurement

» Complicates Responsible Official compliance certification

z With many existing engine types, developing data to 

establish emission limits appears impractical / impossible

z INGAA recommends Work Practices (§112(h) or GACT)

Emission Standards: 

Compliance Implications

z INGAA supports high load performance test (if emission limit)

» Compliance determination at other operating conditions is not clear, 

but rule indicates standards apply “at all times”

» Docket does not include support data and it is understood that 

emissions vary (e.g., CO, HC increase at low load)

» INGAA recommends limiting the standard applicability to this test 

condition (and data used to develop the standard)

– Work practice for other operating conditions?

z Catalysts will be required for all engines with emission limit 

based on uncontrolled MACT Floor

» “Best performing” basis and meet “at all times” 

– Cost-benefit analysis does not consider $$ or market limitations

» Engine replacement required in some cases?

– Engine type or application – too cool for catalyst to work

z Unknowns regarding emissions performance (e.g., SSM, 

reduced load, etc.) prevent “compliance certification”
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Area Source Alternatives

z Most area source engines must meet emission limits

» Thus, catalytic control nearly universally required

z Docket support documentation for this decision is not 

evident

z INGAA recommends GACT work practices for rural area 

source engines

» At a minimum, work practices should be employed for 

smaller engines (e.g., <500 hp) and more remote locations

z Basis for justifying GACT versus MACT should be more 

clearly defined

» Are there data gaps that need to be addressed?

z Are additional subcategories needed?

Major Source Alternatives

z Defining emission limits for SSM events and all operating 

conditions is a monumental task for the array of engines

» Emissions data is not available

» Designing and executing an emissions measurement / data 

collection effort to address technical questions is infeasible

» Serious implementation / enforcement issues also arise

z INGAA recommends Clean Air Act §112(h) options for 

design / work / management practices

» Measurement technical and economic feasibility is at issue

» High load emission limits still apply for nearly all engines; work 

practices address other operating conditions

» Select applications (e.g., air compressors, emergency engines) 

may warrant work practices at all time (i.e., actual operations not 

conducive to enforceable emissions limit)

z INGAA does not believe there is a viable alternative to §112(h)
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Area Source Engines 

Urban versus Rural 

z EPA should analyze urban risk associated with rural ICEs

z If not exempt, rural units should comply via GACT

» Subpart HH approach can be used to differentiate units

z EPA should consider implications of formaldehyde Unit 

Risk Estimate (URE) review and current “best science”

» National Air Toxics Assessment reporting indicates that 

alternative URE is the “current best” science

» Less stringent URE has urban risk and cost-benefit 

implications

» Unfortunately, related IRIS review has been repeatedly 

delayed – potentially important implications for regulation of 

area source natural gas-fired engines 

– e.g., is delisting warranted?

Subcategories

z What is needed to substantiate a Subcategory?

z Fewer subcategories would simplify the rule

» e.g., if above the floor standard is not reasonable, then 

single subcategory by engine type may be warranted rather 

than multiple subcategories by type and size

z Additional subcategories may be warranted to address 

unique attributes. For example:

» Type: 2SLB with lower exhaust temperature

» Application: Cyclic load / short duration operations such as 

air compressors

– Major source units: Work practice may be only viable approach

» Location: Rural engines (especially smaller engines, remote 

engines) with access issues and unique cost/benefit 

considerations
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Management Practices

z INGAA supports broader application of management 

practices versus MACT

z For natural gas-fired engines, operator defined O&M 

similar to new units under NSPS would harmonize 

requirements

z For proposed procedures, frequency must be addressed

» e.g., oil change as frequently as every 8 days

» Any defined timing should be clearly indicated as 

operating hours (not calendar based)

» EPA should consider performance metric based decisions 

for maintenance frequency consistent with current 

practices 

Test Methods and 

Compliance Monitoring

z Formaldehyde tests: Method 323 viability should be more 

closely examined

» INGAA has identified an apparent testing error (human 

error – not Method problem) in test cited in the docket

» Additional Region 8 concerns are implied but not 

documented in the docket

– INGAA has inquired with EPA EMC staff on additional Reports

– Any additional M323 concerns should be clearly discussed

» Without an alternative, FTIR testing only has problems

– Remote access / dual trains required / market access 

– There may an emissions measurement feasibility issue

z Parameter monitoring: EPA intent on parameter 

monitoring requirements is not clear (rule and preamble 

inconsistencies)
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Reporting and Recordkeeping

z For last NESHAP revision, EPA proposed many Part 63 

General Provision requirements but streamlined 

reporting and recordkeeping (R&R) in the January 2008 

Final Rule

z Proposed Rule requires nearly all Part 63 R&R 

» Preamble states EPA intent to minimize burden, but the 

rule does very little to minimize R&R requirements

z INGAA recommends limiting R&R to those activities 

that provide a reasonable cost-benefit

» Identify in the rule those requirements that apply rather 

than general reference to Part 63 General Provisions

» Harmonize with requirements in January 2008 rule

Rule and Implementation Complexity

z This is the 5th significant ICE rulemaking in 5 years

» Breadth of this rule is staggering – number of affected units; 

source types; commercial / residential / industrial

» The January 2008 rule has caused significant 

implementation problems with states

– Challenges are trivial in comparison to the Proposed Rule

» Issue: Can some requirements be harmonized?

z Proposed Rule attempts to address Court decisions

» This is the first rule impacted in many cases

» Based on docket, INGAA could not discern EPA’s intent or 

rationalization for integrating Court decisions into rule

» INGAA recommends separate EPA effort to develop policy 

and guidance memos on Court case integration 

– EPA decisions and process for implementing into NESHAPs
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Schedule: Addressing Data Gaps

z INGAA offers assistance in addressing data gaps

» Significant issues may warrant additional discussion on 

data needs, plans, and timing

– Emissions data – Addressing data needs for emission limits 

is challenging even if all loads and SSM are not addressed

– Costs

– Management practices / Justification of GACT or §112(h)

z For natural gas-fired engines, EPA should consider 

seeking an Extension from the Sierra Club 

» Separate schedule for gas and diesel rules

» Commitment to reasonable schedule and data gathering

z Schedule / deadlines for “additional data” to be provided

z Additional meeting(s) or calls?

Plans / Next Steps

z INGAA will submit comments on June 3

z Current EPA schedule for rulemaking

z How can INGAA assist in addressing data gaps?

» Data needs

» Timing

» Coordination?