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Summary of Meeting with Clean Energy Group 

Regarding the Proposed Stationary Existing RICE NESHAP 

April 15, 2009 

Attendees 

Jaime Pagán, EPA Participants from:

Melanie King, EPA Con Edison 

Michael Horowitz, EPA Florida Power & Light 

Graham Fitzsimons, EC/R NiSource 

Tanya Parise, AGTI Exelon 

Carrie Jenks, M.J. Bradley & Associates 

(moderator for Clean Energy Group) 

National Grid 

PSEG 

 

Purpose of Meeting 

 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). 

Summary of Meeting

General

The Clean Energy Group (CEG) requested this meeting with EPA to discuss the 

recently proposed NESHAP for stationary engines. Clean Energy Group is a coalition 

group focused on the expanded use of clean energy technologies. Clean Energy Group 

has previously worked with EPA on other rulemakings. Participating at this meeting 

were several representatives of CEG member companies (see Attendees). Clean Energy 

Group provided a list of specific questions for EPA, which is included as Attachment 1 to 

these meeting minutes. The list of questions is a collaboration of issues brought up by 

individual member companies. In addition, CEG indicated that each member company 

will be submitting separate comments on the proposed rule. A summary of this meeting 

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

0708). 

Jaime Pagán was asked to provide an overview of the proposed regulation. Jaime 

explained that the proposal is a result of consent decrees on diesel exhaust emissions and 

maximum achievable control technology (MACT) rulemaking in general and is based on 

settlements reached between EPA and environmental groups. The rule was proposed on 

February 25, 2009, and must be promulgated by February 10, 2010, under the consent 

decree. Jaime noted that the public comment period for the proposed rule that was 

originally set at 60 days has been extended by 30 days. 

Jaime indicated that EPA promulgated standards in 2004 for stationary engines 

greater than 500 horsepower (HP) located at major sources. Last year, EPA issued 

regulations for new stationary engines equal to and below 500 HP located at major 
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sources and new stationary engines located at area source. This proposed rule addresses 

stationary engines not previously covered. Plus, the proposed rule addresses existing 

stationary diesel engines greater than 300 HP as a result of the consent decree to target 

diesel exhaust emissions. 

Jaime pointed out that EPA will not be making decisions during this conference 

call, but will try to answer industry’s questions. Jaime noted that EPA will have to 

review all comments received on the proposed rule and then provide recommendations to 

management for final decisions. 

CEG Questions to EPA

As mentioned, CEG had a list of questions for EPA. The complete questions are 

available in Attachment 1 of these meeting minutes and are not repeated in full below. 

1. 40 ppmvd CO Limit 

 The CEG asked what EPA’s intent underlying the 40 parts per million (ppm) 

proposed carbon monoxide (CO) limit is. Jaime responded that the 40 ppm CO limit is 

based on EPA’s MACT floor analysis. The limit is not expected to require add-on 

controls for engines subject to the limit and the level should be achievable without the 

installation of aftertreatment. In response to CEG’s question if a non-numerical standard 

could be considered, EPA replied that a non-numerical standard is not an option for 

stationary engines located at major sources. A non-numerical standard may be an option 

for stationary engines located at area sources, EPA said. EPA noted that it would 

appreciate specific comments related to the proposed management practices. 

2. Engines at Nuclear Plants 

The CEG asked if EPA had specifically looked at stationary emergency diesel 

engines at nuclear plans, which operate less than 200 hours per year, and if a nonnumerical standard could be considered for these units. EPA said that it did not have 

information on engines located at nuclear power plants during the time of rule 

development, but asked CEG members to submit information on engines at nuclear 

power plants. EPA noted that the definition of emergency engines already attempts to 

capture the type of operation that CEG is concerned about. In addition, there is language 

in the emergency engine definition that allows sources to petition for additional hours for 

maintenance and testing purposes. The CEG expressed that it would like to see only 

management practices required for these units and asked why requirements are different 

for the same engine at one location versus another (i.e., major source versus area source). 

The CEG also wanted to know how sources are required to determine compliance with an 

emission limit when no performance testing is required. 

3. and 4.. Engines with Low Operation/Low Fuel Usage 

 The CEG made the point that certain engines with low fuel usage have less 

stringent requirements in some states and have only recordkeeping and reporting 

requirements. The CEG asked if EPA had considered subcategorization based on fuel 
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consumption. EPA responded that it did not consider fuel usage for this proposal, but felt 

that hours of operation was more appropriate. 

5. Engines in Demand Response Programs 

 Regarding demand response programs, EPA indicated that it has made it clear that 

peak shaving operation is not considered emergency operation. Engines used for peak 

shaving are not considered emergency engines and must meet the standards applicable to 

non-emergency engines. Most likely the definition of emergency engines will not 

change, EPA said. Members of CEG noted that they would submit comments on this 

issue. 

6. Engines used for Starting up Combustion Turbines 

In CEG’s list of questions, black start capability is mentioned in which a diesel 

engine is used for starting up combustion turbines. EPA stated that it was not aware of 

diesel engines being used for this purpose, but that it appears from CEG’s description of 

these units that they would likely be considered emergency units. The CEG made the 

point that the engines are technically not emergency because they are capable of going on 

the grid. However, CEG said, the units only run for about 10 minutes at a time and if 

they go beyond 15 minutes they will overheat. In total, these units may run between 10 

and 15 hours per year, according to CEG. Finally, CEG added that there is no other way 

to start the combustion turbines. EPA suggested that CEG provide detailed information 

about these units in their comments, including historical operating information and 

reasons why post-combustion controls are not reasonable. 

7. Performance Testing 

The CEG acknowledged that it may have misunderstood the rule to say that 

emergency engines are subject to performance testing. EPA clarified that emergency 

engines are not subject to performance testing requirements under the proposed rule. 

8. Number of Affected Engines 

The CEG asked how EPA identified the number of engines that would be affected 

by the rule. EPA referred CEG to a memo in the docket, which describes how EPA 

estimated the number of engines that would be affected by the rule. The estimates are 

based on information from Power Systems Research (PSR), which represents the best 

data available. The PSR database is proprietary, but tables with the number of affected 

engines is available in the docket memo. 

9. Urban versus Rural Areas 

The CEG asked if EPA had analyzed urban versus rural impacts of the rule for 

area sources and if different requirements had been considered. EPA said that it has 

evaluated the impacts of engines located at urban areas versus those of engines located at 

rural areas for previous rulemakings affecting stationary engines. EPA determined that 

engines are located everywhere and cannot say that there is a difference between an 
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engine at one location versus another. Therefore, it was determined to regulate all 

engines regardless of location. 

10. Cost per Ton 

Regarding EPA’s above-the-floor analysis, CEG asked what threshold EPA uses 

to determine whether controls are cost-effective or not. EPA said that there is not a clear 

dividing line or specific cost per ton threshold. EPA conducts the above-the-floor 

analysis by looking at it on a source-by-source basis. EPA also considers which 

pollutants are involved. The cost per ton matters in the final decision. EPA told CEG 

that the cost per ton estimates for the proposed rule are in the docket. 

11. and 12. High Load/SSM Limits 

Regarding EPA’s proposed limits, EPA said that they are supposed to be met at 

all conditions. The proposed limits during startup and malfunction are based on a recent 

court decision, which did away with the general language in the General Provisions, 

which exempted sources from requirements during startup, shutdown and malfunction. 

 
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Attachment 1 

List of CEG Questions 

The following are questions we would like to discuss with you during our call on 

Wednesday, April 15 at 3:00 regarding EPA’s RICE proposal: 

1. Please explain EPA's intent underlying the 40 ppmvd CO standard for existing 

emergency compression ignition (CI) engines > 500 HP located at area sources? 

Does EPA consider the standard to be one that can be met by existing CI engines 

without controls? Could a non-numeric standard be considered for these 

emergency CI engines similar to some of the other standards included in the 

proposal (e.g., based on manufacturer recommended services?) 

2. Emergency diesel generators at nuclear plants typically operate less than 200 

hours per year, and the NRC prohibits these units from supplying electric power 

to the grid. Thus, operations at these generators are limited to NRC-mandated 

testing and emergency situations only. Did EPA consider a subcategory for these 

units, and could EPA exempt these units based on the annual operational hours? 

If not, could a non-numeric standard apply to these units similar to some of other 

standards included in the proposal (e.g., based on manufacturer recommended 

services)? 

3. Some distribution company service buildings have emergency combustion 

engines > 500 HP located at area sources. These typically operate under 50-100 

hours per year. Similar to the above question, did EPA consider a subcategory for 

these units, and could a non-numeric standard apply to these units similar to some 

of other standards included in the proposal (e.g., based on manufacturer 

recommended services)? 

4. Some small engines are unregulated in some states because they remain below a 

certain fuel usage amount per year, but these facilities do comply with record 

keeping requirements. Similar to the above question, did EPA consider a 

subcategory for these units, and could a non-numeric standard apply to these units 

similar to some of other standards included in the proposal (e.g., based on 

manufacturer recommended services)? 

5. Has EPA considered the impact of the proposed standards on participation in PJM 

demand response programs? Given that the number of emergency events are 

limited number, can the following provision in Section 63.6640 be modified to 

allow the continued participation of emergency IC engines in demand response 

programs for a limited number of hours per year?: 

"... There is no time limit on the use of emergency stationary ICE in 

emergency situations. The owner or operator may petition the 

Administrator for approval of additional hours to be used for 

maintenance checks and readiness testing, but a petition is not required 

if the owner or operator maintains records indicating that Federal, 

State, or local standards require maintenance and testing of emergency 
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RICE beyond 100 hours per year. Emergency stationary RICE may 

operate up to 50 hours per year in non-emergency situations, but those 

50 hours are counted towards the 100 hours per year provided for 

maintenance and testing. The 50 hours per year for non-emergency 

situations cannot be used for peak shaving or to generate income for a 

facility to supply power to an electric grid or otherwise supply power 

as part of a financial arrangement with another entity. For owners and 

operators of emergency engines, any operation other than emergency 

operation, maintenance and testing, and operation in non-emergency 

situations for 50 hours per year, as permitted in this section, is 

prohibited." 

6. Since the early 1960s every major power plant in the US has been required to 

have black start capability. This is typically involves a small combustion turbine 

(CT) equipped with a diesel engine used for startup of the CT, generally the 

engine operates less than 10 minutes per CT start. The majority of these black 

start units only operate a few times per year. Requiring post combustion controls 

on units will reduce dependability and significantly increase cost, with little 

change of an actual reduction in emissions as these engines rarely run long 

enough for a CO catalyst or SNCR system to reach minimum operating 

temperatures. Could emission controls for engines of this type be limited to 

mechanical maintenance requirements coupled with restrictions on per event 

operating times and annual hours of operation? 

7. RICE units covered by the proposal are required to be tested every 8760 hours of 

operation, or every three years, which every comes first. For many emergency 

generators, or emergency fire pumps, operation during stack testing could 

represent a major percentage of the units operating time. To require significant, 

and expensive, post combustion controls that require testing on units of this nature 

could results in an actual increase in total emissions since there is a significant 

warm-up period for catalysts and/or SNCRs during which emissions with be 

elevated. Did EPA evaluate this consequence? 

8. The rule will affect nearly every existing stationary engine in the U.S. - including 

small generators at facilities that have not required permitting or been associated 

with air regulations (e.g., heath care facilities, homeowners, fire houses, small 

remote facilities with a single small engine for power). How did EPA identify the 

total number of affected sources and is there outreach underway to inform the 

affected stakeholders? 

9. Since Section 112(k) focuses on urban impacts from area sources, did EPA 

analyze urban versus rural impacts from area source engines and consider 

different requirements for urban versus rural engines? 

10. EPA's analysis for "beyond the floor" control concludes that catalytic control is 

cost effective for several subcategories. What is the $ per ton cost effectiveness 

threshold that differentiates cost effective controls from controls that are not cost 
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effective? If not a brightline, is there an approximate cost range for the cost 

effectiveness threshold? 

11. The rule retains the "high load" test requirement when performance tests are 

required. However, the Proposed Rule indicates that emission limits apply at all 

loads and during shutdown, with different limits for startup and malfunction 

periods in most cases. Please explain EPA's underlying reasoning. For example: 

Does EPA have data indicating that low load operation can meet the uncontrolled 

baseline or that catalyst performance of 90% is achievable at reduced load? How 

can an operator certify Title V compliance if off-load performance is uncertain 

and has not been demonstrated by EPA? 

12. Please explain EPA's conclusion that emissions during startup, shutdown and 

malfunction are commensurate with the "MACT floor" emission limit (average of 

the best performing 12% of similar units without catalytic control)? Could EPA 

consider alternatives under Section 112(h) for setting SSM limits?