1 MEMORANDUM Subject: Response to Public Comments on Proposed Amendments to the Standards of Performance for Stationary Compression Ignition and Spark Ignition Internal Combustion Engines

From: Melanie King, Energy Strategies Group

To: EPA Docket EPA-HQ-OAR-2010-0295

On June 8, 2010, EPA proposed amendments to the standards of performance for stationary compression ignition (CI) and spark ignition (SI) internal combustion engines in 40 CFR part 60, subparts IIII and JJJJ. The purpose of this doc ument is to present a summary of the public comments that EPA received on the proposed sta ndards and the responses developed. This summary of comments and responses serves as the basis for revisions made to the requirements between proposal and promulgation. EPA received 32 public comments on the proposed rule. A listing of all persons submitting comments, their affiliation, and the Document ID for their comments is presented in Table 1. The comments can be obtained online from the Federal Docket Management System at http://www.regulations.gov . The docket number for this rulemaking is EPA-HQ-OAR-2010- 0295. In this document, commenters are identified by the last two digits of the Document ID of their comments.2 Table 1. List of Commenters on the Proposed Amendments to Standards of Performance for Stationary CI and SI Internal Combustion Engines

Document ID Commenter/Affiliation EPA-HQ-OAR-2010-0295-0021 Dan Chisholm Sr. MGI Systems, Inc. EPA-HQ-OAR-2010-0295-0022 EPA-HQ-OAR-2010-0295-0055 Matt Todd Policy Advisor American Petroleum Institute EPA-HQ-OAR-2010-0295-0023 EPA-HQ-OAR-2010-0295-0053 Alice Edwards Acting Director, Division of Air Quality State of Alaska Department of Envi ronmental Conservation, Division of Air Quality EPA-HQ-OAR-2010-0295-0024 Don C. DiCristofaro President Blue Sky Environmental, LLC EPA-HQ-OAR-2010-0295-0026 Dan E. Brann Manager, Emissions Compliance Electro-Motive Diesel, Inc. EPA-HQ-OAR-2010-0295-0027 James L. Kavanaugh Director State of Missouri Department of Natural Resources EPA-HQ-OAR-2010-0295-0028 EPA-HQ-OAR-2010-0295-0029 (duplicative comment) EPA-HQ-OAR-2010-0295-0045 Ali Mirzakhalili Director State of Delaware Department of Natural Resources and Environmental Control Division of Air Quality EPA-HQ-OAR-2010-0295-0030 EPA-HQ-OAR-2010-0295-0052 Rich Counihan Enernoc (on behalf of CPower, Inc., EnergyConnect, Inc., EnerNOC, Inc., Innoventive Power LLC. EPA-HQ-OAR-2010-0295-0031 Don Mark Anthony Air Quality Engineer Alyeska Pipeline Service Company EPA-HQ-OAR-2010-0295-0032 Allen Gillette Senior Vice President of Engineering Generac Power Systems, Inc.

EPA-HQ-OAR-2010-0295-0033 John S. Lyons Director Commonwealth of Kentucky Ener gy and Environment Cabinet Department for Environmental Pr otection Division of Air Quality EPA-HQ-OAR-2010-0295-0034 David Meierhenry EPA-HQ-OAR-2010-0295-0035 Jim Moxley Healthsouth EPA-HQ-OAR-2010-0295-0036 Joseph Kubsh Executive Director Manufacturers of Emission Controls Association3 Document ID Commenter/Affiliation EPA-HQ-OAR-2010-0295-0037 EPA-HQ-OAR-2010-0295-0057 Timothy A. French General Counsel Joseph L. Suchecki Director, Public Affairs Engine Manufacturers Association EPA-HQ-OAR-2010-0295-0038 Bill Wemhoff Sr. Principal, Environmental Policy National Rural Electric Cooperative Association EPA-HQ-OAR-2010-0295-0039 Mark Underhill Emissions Specialist Foley Engine Systems EPA-HQ-OAR-2010-0295-0040 Supports the comments of EPA-HQ-OAR-2010-0295-0037 Brady Winkleman Caterpillar, Inc.

EPA-HQ-OAR-2010-0295-0041 Arthur W. Iler Assistant General Counsel Midwest Independent Transmission System Operator, Inc. EPA-HQ-OAR-2010-0295-0042 William M. Nugent Executive Director New England Conference of Public Utility Commissioners EPA-HQ-OAR-2010-0295-0043 Lisa Beal Director, Environment and Construction Policy Interstate Natural Gas Association of America EPA-HQ-OAR-2010-0295-0044 Anna Garcia Executive Director Ozone Transport Commission EPA-HQ-OAR-2010-0295-0046 Mike Wasson Director, North America Fleet Services Exterran EPA-HQ-OAR-2010-0295-0047 Jack Mitchell Senior Consultant Trinity Consultants EPA-HQ-OAR-2010-0295-0048 Cynthia A. Finley Director, Regulatory Affairs National Association of Clean Water Agencies EPA-HQ-OAR-2010-0295-0049 Kate Williams Regulatory Affairs Representative Alaska Oil and Gas Association EPA-HQ-OAR-2010-0295-0050 John Dutton GCA HSE Committee Chairman Gas Compressor Association4 Document ID Commenter/Affiliation EPA-HQ-OAR-2010-0295-0051 Support the comments of EPA-HQ-OAR-2010-0295-0050 EPA-HQ-OAR-2010-0295-0055 John Dutton Manager of Operations J-W Power Company EPA-HQ-OAR-2010-0295-0054 Support the comments of EPA-HQ-OAR-2010-0295-0055 Dan F. Hunter Manager, Regulatory Issues ConocoPhillips5 Summary of Public Comments and Responses The summary of public comments and responses is organized as follows:

1.0 General

2.0 10-30 Liters/Cylinder Displacement Engines

3.0 ≥ 30 Liters/Cylinder Displacement Engines

4.0 Operating and Maintenance Requirements

5.0 Alaska

6.0 Temporary, Replacement, and Marine Engines

7.0 Digester Gas Engines

8.0 Test Methods

9.0 Definitions 9.1 Reconstruction 9.2 Date of Manufacture 9.3 Installed 9.4 Certified Emissions Life 9.5 Emergency Engines 9.6 Freshly Manufactured Engines

10.0 Miscellaneous6 1.0 General

1.1 Comment : Two commenters (22 and 23) requested that EPA provide additional time to submit comments on the proposed amendments to 40 CFR part 60, subparts IIII and JJJJ. Commenter 22 specifically asked that EPA pr ovide a 30-day extension period for providing

comments.

Response : EPA provided a 30-day extension to the public comment period to allow additional time for commenters to prepare and submit their comments.

1.2 Comment : One commenter (37) expressed genera l support of EPA’s proposed amendments to 40 CFR part 60, subparts IIII and JJJJ. Speci fically, commenter 37 said that the changes proposed by EPA are positive because they generally provide more flexibility and address

various issues associated with the regulations as th ey currently exist.

Response : No response is needed.

1.3 Comment : One commenter (33) indicated that ther e is confusion regard ing the applicability of 40 CFR part 60, subpart JJJJ and 40 CFR pa rt 63, subpart ZZZZ, to new stationary SI emergency engines. The commenter (33) said that 63.6590(c) of the final National Emission Standards for Hazardous Air Pollutants (NESHAP) is confusing and the commenter (33) believes the paragraph contradicts the New Source Perf ormance Standards (NSPS) for stationary SI engines. For example, the commenter’s (33) understanding per 63.6590(c) is that an emergency7 SI engine built in 2007 could comply with the NESHAP by meeting the requirements in the SI NSPS. However, the commenter (33) believes this contradict s 40 CFR part 60, subpart JJJJ, because new emergency SI engines built in 2007 are not subject to this regulation according to 60.4230(a)(4)(iv). The commenter ( 33) said that emergency SI engines constructed between June 12, 2006, and before January 1, 2009, are not subject to 40 CFR part 60, subpart JJJJ, and consequently are not subject to any requirements. The commente r (33) argued that 40 CFR part 60, subpart JJJJ should require th ese engines and other engines that are not subject to any requirements to at least meet work practice st andards. Additionally, commenter 33 expressed that emergency engines should be subject to the same operational limitations as other emergency engines that are subject to 40 CFR part 60, subpart JJJJ.

Response : Stationary SI engines less than or equa l to 500 horsepower (HP) that are located at major sources of hazardous air pollutant (HAP) em issions and stationary SI engines of any size

that are located at ar ea sources of HAP emissions that ar e considered new under 40 CFR part 63, subpart ZZZZ, but that pre-date NSPS applicab ility under 40 CFR part 60, subpart JJJJ, are not subject to any requirements. However, revisions to the substance of 40 CFR part 60, subpart JJJJ are beyond the scope of this rule, which deals primarily with revisions to 40 CFR part 60, subpart IIII and merely includes some minor revi sions to 40 CFR part 60, subpart JJJJ to be consistent with the changes made to 40 CFR part 60, subpart IIII and to correct minor errors. EPA intends to address this issue during EPA’s review of 40 CFR part 60, subpart JJJJ in the

near future.8 1.4 Comment : One commenter (39) indicated that it would be beneficial if EPA published

material that could be used to calculate costs for determining rebuild costs to compare to the costs of a new engine. Specifi cally, commenter 39 suggested that a spreadsheet could be made available, which could be used as a template for this purpose. Such a tool would ensure regulation consistency and eliminate confusion b ecause there are currently numerous different interpretations of the requirements, according to the commenter (39).

Response : EPA is not developing such material at this time, but will consider providing guidance material in the future

1.5 Comment : One commenter (44) recommended that EPA limit the sulfur content in the fuel to 15 parts per million (ppm) for stationary engines as soon as possible, as is currently required for on-road and nonroad engines. This would be consistent with the Nort heast and Mid-Atlantic States’ commitment to pursue low sulfur in fuel limits to assist in reaching State implementation plans regional haze goals.

Response : 40 CFR part 60, subpart IIII already limits th e sulfur content in diesel fuel to 15 ppm for the majority of engines subject to the NSPS.

1.6 Comment : One commenter (44) said that the sta ndards being proposed for stationary engines

should be consistent with the sta ndards that have already been fi nalized for nonroad engines. In addition, the commenter (44) recommended that th ese standards apply to portable engines that9 remain on site for more than 30 days and does not believe these engines should be considered portable engines.

Response : EPA’s approach is designed exactly according to what the commenter is requesting and EPA agrees with the commenter that the standards should be consistent with nonroad standards for similar engines. Regarding the commenter’s recommendation for portable engines that remain on site for more than 30 days, th e definition of nonroad engine requires that a portable engine be at a non-seasonal location for at least a year before it is considered stationary. That is a longstanding definition th at was not revisited in this ru le and is beyond its scope. Also, the commenter did not provide any reasons fo r changing this longstanding definition.

1.7 Comment : One commenter (44) sugge sted that the final rule include additional provisions that are being considered to be included in the Ozone Transport Commission model rule, which is currently being drafted. The suggested prov isions include monitori ng and data reporting on generator usage, combined heat and power incentives and innova tive technologies, and emissions standards for demand response programs, the commenter (44) said.

Response : These comments are not in the scope of the rulemaking and have not been provided with enough specificity to ta ke any further action.

1.8 Comment : One commenter (38) cited to several rulemakings EPA has promulgated over the years for stationary internal combustion engine s under sections 111 and 112 of the Clean Air Act (CAA). The commenter (38) expressed that ther e are inconsistencies between the various rules10 and there is confusion among the regulated comm unity. The commenter (38) acknowledged in its comments that EPA has attempted to provide some consistency between regulations, e.g., by EPA’s proposal to revise the emergency engine definition. The commenter (38) requested that consistency be provided for e ngines under 40 CFR part 63, subpart ZZZZ, and referred to the subcategory of existing non-emerge ncy SI engines that operate 24 hours of less per year that was included in the August 2010 amendments to that s ubpart. Those engines may comply with work practices, the commenter (38) said, and the commen ter (38) believes that it would be justified to also establish an equivalent s ubcategory for stationary non-emerge ncy CI engines that operate 24 hours or less per year. According to the commen ter (38), stationary CI engines that operate 24 hours or less per year emit low emissions and can be used in situations that are not allowed if the engines were considering emergenc y engines. The commenter (38) requested that EPA add this provision to the final rule, or alternatively address this issue under the stationary CI

reconsideration.

Response : Amendments to 40 CFR part 63, subpart ZZZZ are outside the scope of this rulemaking.

2.0 10-30 Liters/Cylinder Displacement Engines

2.1 Comment : Several commenters (26, 36, 37, and 44) in dicated that they agree that it is appropriate to extend the nonroad engine standards that were recently finali zed to stationary CI engines with a displacement between 10 a nd 30 liters per cylinder (l/cyl). Commenter 26 also supported EPA’s proposed changes to incorporate 40 CFR part 1042

under the 60.4201 and 60.4202 of the CI NSPS and a pply those requirements to appropriate11 displacement stationary engines. In the commenter’s (26) opinion, if this provision is finalized it will result in significant emissions reductions at a low cost.

Response : No response is needed.

2.2 Comment : One commenter (37) said that 60.4201 of the proposed CI NSPS is correct, but that Table 2 in the preamble to the proposed rule is not accurate. A ccording to commenter 37 there are no Tier 3 particulate matter (PM) standards for marine engines between 15 and 30 l/cyl that are above 2,000 kilowatt (KW), but there are Tier 3 nitrogen oxides (NO x ) standards for marine engines between 7 and 15 l/cyl. EPA should correct Table 2 of the preamble to match the rule, the commenter (37) said. The commenter (37) also indicated that section 60.4202(f) of the proposed rule that contains requirements for stationary emergency CI engines between 10 and 30 l/cyl is incorrect.

Commenter 37 said that EPA refers to Tier 3 em ission standards in that section, but there are no Tier 3 emission standards for comparable marine engines. According to the commenter (37), 40 CFR part 1042, which is the section that EP A cites in 60.4202(f) of the proposed rule, specifically excludes all marine CI engines above 3,700 KW as well as marine CI engines above 2,000 KW with displacements between 15 and 30 l/cyl from Tier 3 standards. Therefore, the commenter (37) said, the standard s that EPA cites in 60.4202(f) of the proposed rule do not exist. The commenter (37) reiterated why EPA determined that there should be no Tier 3 standards for similarly sized marine CI engines under the marine rule and that it agreed with that previous determination. The commenter (37) asked that EPA correct the section in question in the12 proposed rule and state in the final rule that stationary emergency CI engines under 60.4202(f)

meet Tier 2 and not Tier 3 ma rine engine standards.

Response : EPA agrees with the commenter and notes that there were inadve rtent errors in the preamble and regulatory language of the proposed rule. On th e first issue regarding the standards being presented incorrectly in the preamble to the proposed rule, EPA concurs with the commenter. The Tier 3 standards are correctly la id out in the final preamble and are also shown

in Table 2 below. Table 2. First Tier of Standards for Stationary CI Engines with a Displacement ≥ 10 and <30 Liters per Cylinder

Engine Size – Liters per Cylinder, Maximum Engine Power PM g/HP-hr (g/KW-hr) NO x +HC g/HP-hr (g/KW-hr) Model Year

10.0 ≤ displacement<15.0 <2,000 KW 0.10 (0.14) 4.6 (6.2) 2013+

10.0 ≤ displacement<15.0 2,000 ≤ KW<3,700 0.10 (0.14) 5.8 (7.8) 2013+

15.0 ≤ displacement<20.0 <2,000 KW 0.25 (0.34) 5.2 (7.0) 2014+

20.0 ≤ displacement<25.0 <2,000 KW 0.20 (0.27) 7.3 (9.8) 2014+

25.0 ≤ displacement<30.0 <2,000 KW 0.20 (0.27) 8.2 (11.0) 2014+

On the second issue regarding the standards in section 60.4202(f) of the proposed rule being incorrect, the commenter is correct and EPA agrees that the same standards that apply to marine CI engines should apply to stationary CI emergency engines that have the same size and displacement. Tier 2 emission st andards should apply to these e ngines where there are no Tier 313 marine engine standards for comparable engines. Subsequently, EPA is including language in

the final rule that clarifies this.

2.3 Comment : One commenter (37) asked that EPA harmonize the displacement (l/cyl) cutoff between medium speed and high speed stationary engines. Commenter 37 recommended that EPA change the displacement threshold where sta tionary engines have to meet marine engine standards from 10 l/cyl to 7 l/cyl. The commenter ( 37) believes that most if not all engines with a displacement from 7 to 10 l/cyl are produced for marine purposes and for that reason suggested that the displacement threshold be aligned. One commenter (37) asked that EPA provide 4 years of lead time from promulgation of the CI NSPS until the standards phase-in. Acco rding to the commenter (37), medium speed marine and stationary engines have similar desi gns, but generally require separate development programs based on certain differences.

Response : The standards for marine engines of 7 l/cyl to 10 l/cyl displacement are not as stringent as the standards that have already been in place for several years for stationary engines with a displacement of 7 l/cyl to 10 l/cyl. The commenter did not provide compelling information to justify reducing the stringency of th e standards for stationary engines of this size

range.

3.0 ≥ 30 Liters/Cylinder Displacement Engines

3.1 Comment : Three commenters (36, 37, and 44) indi cated that they are supportive of the proposed amendments, which more closely align emission standards for stationary CI engines14 with a displacement of 30 l/cyl and above with those that apply to similar nonroad engines. EPA proposed this change in 60.4204 and 60.4215 of 40 CF R part 60, subpart IIII. The commenter (37) said that the current limits, which are eith er emission standards or percent reduction limits, are not necessarily technically or economically feasible for these engines. The current requirements put engines with a displacemen t at or above 30 l/cyl at a disadvantage economically in comparison to other large engine s or combustion technologies, according to the commenter (37). The commenter (37) said that finalizing emission standards for large displacement engines that are more consistent with the Internationa l Maritime Organization (IMO) marine engine standards, will mean that the standards are technically and economically feasible and would allow the lead time necessary to implement appropriate emissions control technologies for these engines. Large displacemen t stationary engines are derived from marine engines, but generally have di fferent turbo specifications because of different loading optimization needs, the commenter (37) said.

Response : No response is needed.

3.2 Comment : One commenter (37) said that in the final rule EPA needs to add stipulated

allowances from sections 6.3.11 and 6.4.13 of the IMO Marine Environment Protection Committee (MEPC) 58 Revised ANNEX VI fr om October 2008 to sections 60.4204 and 60.4215

of the rule.

Response : EPA contacted the commenter for additional information on what the IMO allowances are and what the commenter is reques ting that EPA allow for stationary CI engines15 with a displacement of 30 l/cyl and above. In response to EPA’ s request, the commenter replied 1 that it no longer believes that it would be n ecessary to incorporate the IMO allowances and subsequently withdrew its comments on this issue. Therefore, no further action is needed on this

issue.

3.3 Comment : One commenter (37) said that in the pr eamble to the proposed amendments in the third column of page 32616 and the first column of page 32617, the emissions in parentheses are shown in grams per kilowatt-hour (g/KW-hr), but they should be in grams per HP-hour (g/HPhr).

Response : The commenter is correct that these st andards were presented incorrectly in the preamble to the proposed rule.

3.4 Comment : Two commenters (37 and 48) expressed su pport of EPA’s proposal to not require aftertreatment-forcing standards for stationary emergency engine s with a displacement at or above 30 l/cyl. Commenter 48 spec ifically noted support for the NO x standards not necessitating aftertreatment in the proposed ru le. According to the commenter (37), these engines are used to power emergency generators, especially in criti cally sensitive installations like nuclear power plants. The commenter (37) said that adding afte rtreatment to these large engines in order to reduce emissions could potentially significantly affect the perfor mance and reliability of the emergency engine and aftertreatment is not co st-effective. For these reasons, which the commenter (37) said that EPA has used in the past to justify standards for smaller emergency

1 Email from Joe Suchecki, Engine Manufacturers Associatio n to Melanie King, EPA. Request for Clarification on Comment Regarding IMO Allowances. February 22, 2011.16 engines, commenter 37 believes that aftertreat ment should not be requ ired of stationary emergency engines with a displacement at or ab ove 30 l/cyl. The commenter (37) urged EPA to finalize the proposed changes on page 32617 of the preamble and in 60.4205 of the proposed rule. Also, commenter 37 said that EPA should include the allo wances requested in comment 3.2 (6.3.11 and 6.4.13 of the IMO MEPC 58 Revised ANNEX VI from October 2008) for these engines as well.

Response : No response is needed to the first pa rt of this comment regarding the proposed standards for emergency engines with a displacement of 30 l/cyl or more. Regarding the IMO allowances, EPA contacted the commenter for additional information. In response to EPA’ s request, the commenter replied 2 that it no longer believes that it would be necessary to inco rporate the IMO allowances an d subsequently withdrew its

comments on this issue.

3.5 Comment : One commenter (37) indicat ed that it thought there wa s an error in the proposed rule on page 32623 in 60.4205(d)(2). Acco rding to the commenter (37), the NO x standard that applies to emergency engines should be applicab le past the year 2016 and the commenter (37) suggested that EPA take out the text “and before January 1, 2016.”

Response : The commenter is correct and EPA ha s made this clear in the final rule.

3.6 Comment : One commenter (37) supports a fuel lim it of 1,000 ppm sulfur content for engines with a displacement at or above 30 l/cyl. The commenter (37) ag rees that it is appropriate to

2 Id.17 align fuel requirements for stationa ry engines with a displacement at or above 30 l/cyl with those that are in the IMO marine engine standards, si nce the stationary engine emission standards are also being aligned with IMO mari ne engine standards. However, the commenter (37) asked that EPA require that this limit b ecome effective immediately a nd not in 2014, as proposed. The commenter (37) claimed that 500 pp m sulfur fuel, which is the sulfur level stationary engines with a displacement at or above 30 l/cyl currently must meet for the fuel they use, will become very limited and perhaps unavailable after the 15 ppm sulfur fuel requirements take effect in

October 2010 for most mobile and stationary engines. Engines w ith large displacement are not designed to operate on 15 ppm su lfur fuel, the commenter (37) argued, therefore, appropriate fuel for these engines may not be available, or if it is, will be significantly more costly. To ensure the availability of appropriate fuel, th e commenter (37) asked that EPA allow engines with a displacement at or above 30 l/ cyl to use 1,000 ppm immediately.

Response : EPA agrees that it would be appropriate to require that stationary engines with a displacement of 30 l/cyl or more limit the sulf ur content in the fuel to 1,000 ppm beginning earlier than 2014, which is the timeframe that wa s proposed. However, EPA disagrees with the commenter’s logic and that the requirement should become effective immediately. Diesel fuel containing 500 ppm sulfur will be the designated off-spec fuel within the diesel stream until

2014 and should be available at least for locomo tives and marine engines until June 1, 2012. Therefore, EPA believes it is appropriate to fi nalize the 1,000 ppm fuel requirement for large displacement engines, bu t require that these engines begin using this fuel on June 1, 2012. EPA has made this clear in 60.4207(d) of the final rule.18 3.7 Comment : One commenter (37) supports the proposal to require a PM emission standard of 0.40 g/KW-hr for engines with a displacement at or above 30 l/cyl. According to the commenter (37), it is not technically feasible to achieve th e limits for PM that are in the current final rule without the use of low sulfur fuel, nor is it feasible for emergency engines.

Response : No response is needed.

4.0 Operating and Maintenance Requirements

4.1 Comment : One commenter (37) expressed concer n about the proposal that for certified engines, owners and operators would be allowe d to develop and follow their own operation and maintenance (O&M) procedures as an altern ative to following the manufacturer’s O&M procedures. Commenter 37 recommended that e ngines that do not follow the manufacturer’s O&M procedures be considered as operating in a non-certified manner and subject to initial performance testing requirements. The commente r (37) indicated that it is supportive of providing additional flexibility, but that in those cas es where an owner or operator opts to take an alternative O&M approach, which differs from what the manufacturer recommends for the engine, the engine manufacturer or certificate holder should no longer be responsible for emissions compliance. EPA should make that cl arification as to who is responsible for the emissions from the engine and if operated di fferently than recommended by the manufacturer, the engine should no longer be clas sified as a certified engine. The commenter (37) also recommended that in order to avoid di sputes regarding who would be the responsible party in cases where alternative O&M procedures are being followed, that EPA establish a mechanism for owners and oper ators to identify specific engines or facilities19 where such procedures are being used. In the ab sence of such designation, the regulatory agency and the engine manufacturer would not know if the engine is maintained according to the manufacturer’s guidelines and conf lict could arise if there is a deviation. The commenter (37) suggested the owner or operator could apply a permanent label to the engine, if the engine had been altered beyond the manufacture r’s recommended O&M procedures. Commenter 37 additionally noted concern over the proposed provi sion in 60.4211(g) that allows owners and operators to adjust engi ne settings outside of the manufacturer’s recommendations. The commenter (37) is of th e opinion that such adju stment should only be allowed in association with performance testing and the commenter (37) re quested that clarifying language be included in the final preamble and ru le. All engines with a displacement below 30 l/cyl are under 40 CFR part 60, subpart IIII, requir ed to be certified, and commenter 37 said that

the certification and emissions compliance are contingent upon th e engine being operated within certain parameters and settings. Therefore, if these settings are change d, the engine may be out of compliance, the commenter (37) said, a nd such actions significantly affect engine performance and emissions levels. Conseque ntly, the commenter (37) recommended that changing CI engine settings only be permitted under the following conditions:

 If the factory settings are changed by the ow ner or operator, an in itial performance test

should be conducted to confirm that the emission standards ar e still being met;

 EPA clearly indicates in the final rule that if factory settings are changed, the engine manufacturer is no longer responsible for the engine being in compliance with the standards and the emissions warranty becomes void at the time of the adjustment and after;

 The engine is no longer cons idered a certified engine;20  The owner or operator of the engine alerts the regulatory agency with a notification including the engine serial number that it is adjusting the engine settings beyond the

manufacturer’s recommendations and that acknowledges that the engine is no longer considered a certified engine under the sta tionary (or nonroad, if applicable) regulation,

and

 The owner or operator applies a permanent label to the engine to indicate that it had been altered beyond the manu facturer’s settings. The commenter (37) urged EPA to make it clear that the additional flexibility provided in the final rule by permitting engine settings to be adjusted beyond manufacturer’s recommended specifications means that the manufacturers are still required to sell only new certified stationary engines and that when owners and operators purchase new engines subject to the NSPS, they have to purchase new NSPS-certified engines. The commenter (37) specifically

said that EPA should make it clear in the fi nal rule that the provision for owners and operators to operate a certif ied engine in a non-certified manner, does not mean that manufacturers are permitted to sell new engines that are subject to the NSPS that are noncertified nor does it mean that owners and operators can buy new non-certified NSPScovered engines.

Response : EPA agrees that the engine manufacturer should not be held responsible once owners and operators of a certified engine no longer opera te and maintain the engine and control device according to the manufacturer’s O&M procedures. This is consistent with the language in

section 207 of the CAA and 40 CFR 1068.505, regarding mobile sour ce engines, that specifies that EPA not require a recall of engines by th e manufacturer unless EPA determines that a21 substantial number of engines, a lthough properly maintained and used , do not conform to emission regulations. EPA thinks th at it is clear in the rule langua ge that the owner/operator, not the manufacturer, is required to show compliance in such situations, as was specifically laid out in 60.4211(g) of the proposed rule. Further, EPA st ated in the preamble to the proposed rule that engines operated in this manner would be consid ered non-certified engines and generally subject to performance testing (see 75 FR 32615, middle column). Regarding the commenter’s recommendation that engines that do not follow the manufacturer’s O&M procedures be considered as operating in a non-certified manner and subject to initial perf ormance testing, EPA points to 60.4211(g) of the proposed rule, which requires all engines greater than 100 HP to conduct a performance te sting. Engines greater than 500 HP also have to conduct subsequent te sting every 8,760 hours of operation or 3 years, whichever comes first. Also, ow ners and operators of engines that are less than 100 HP, where the engine and control device are not installed and configured according to the manufacturer’s

emission-related written instructions or if the emission-related sett ings are changed in a way that is not permitted by the manufactur er, an initial performance test has to be conducted. Again, EPA cites to the preamble to the proposed ru le where EPA explained that in cases where owners/operators take an altern ative approach and follow their own O&M procedures versus the manufacturer’s procedures, EPA will need more assurance that the engine is meeting the emission standards and consequent ly generally subject these engi nes to performance testing. Regarding the comment about identifying speci fic engines or facili ties where alternative procedures are being used, EPA points out that in 60.4211(g) of the proposed rule it is required of owners/operators who follow a lternative procedures to keep a maintenance plan and records of conducted maintenance. Therefore, documen tation of the maintenance conducted would be22 available and would indicate if the engine is being maintained according to the manufacturer’s guidelines or not. Therefore, EPA does not anticip ate that a conflict would arise as to who is the responsible party for demonstrat ing compliance. For this reas on, EPA does not believe that applying a permanent label to the engine would be necessary.

EPA notes that there was an inadvertent er ror in the proposed rule language at 60.4211(a) and (c) where EPA incorrectly referred to subs ection 60.4211(f) of the proposed rule. In the final rule, EPA correctly references pa ragraph (g) of 60.4211 in 60.4211(a) and (c).

4.2 Comment : One commenter (48) expressed th at it is supportive of gearing O&M requirements toward the engine manufacturers, as opposed to the owners and operators. However, the commenter (48) said that it is concerned with how owners and operators would comply with manufacturer’s O&M procedures rela ted to emissions. These requirements are not written as permit enforceable documents and the commenter (48) anticipates several inadvertent violations, which in the comment er’s (48) opinion would not n ecessarily mean an increase in emissions. The commenter (48) acknowledged the proposed amendments that incorporate additional compliance flexibility in this area; ho wever, the option to use alternative procedures requires a compliance test to be conducted on engines above 100 HP. According to the commenter (48), compliance testing will be costly and prohibitive for wastewater plants effectively eliminating the option to following alternative O&M procedures. The commenter (48) feels that EPA should exte nd the provision that allows e ngines below 100 HP to simply keep a maintenance plan to larger engines as well.23 Response : EPA disagrees that a performance test should not be required for this group of engines. Assurance is needed to demonstrate that the limits are be ing met. Also, it is not true that all engines below 100 HP are not required to conduct performance testing. If owners and operators of stationary CI engines below 100 HP do not install and configure their engine and control device according to the manufacturer’s emi ssion-related written instructions or change emission-related settings in a way that is not permitted by the manu facturer, an initial performance test is required (see proposed 60.4211(g )(1)). The requirement has been retained in the final rule. Also, under the SI NSPS, owners and operators meeting standards in section 60.4233(d) or (e) that have non-cert ified engines between 25 and 500 HP are subject to testing (see 40 CFR 60.4243(b)(2)(ii)).

5.0 Alaska

5.1 Comment : One commenter (37) believes there is an oversight in th e language in 60.4216 of the proposed rule and asked that EPA clarify in the final rule that stationary engines with a displacement of greater than 30 l/cyl that are lo cated in Alaska are not required to use 15 ppm sulfur fuel, which it believes EPA does not in tend requiring. The commenter (37) suggested removing the reference to 40 CFR part 69.

Response : EPA agrees with the commenter and rec ognizes that the langua ge in 60.4216(a) is misleading in terms of the fuel required for larger displacement engines. EPA has clarified in the final rule that 60.4216(a) is limited to engines w ith a displacement of less than 30 l/cyl.24 5.2 Comment : One commenter (37) expressed support for EPA’s proposal to include different requirements for stationary CI engines located in Alaska, i.e., those proposed in 60.4216 of the CI NSPS. The commenter (37) al so believes that those changes need to be incorporated for engines with a displacement 30 l/ cyl or greater and suggested th at EPA may have inadvertently not included those engines when adding those provisions.

Response : EPA agrees that the provisions in 60. 4216(c) of the proposed rule should not be limited to stationary CI engines with a displ acement below 30 l/cyl, but should also include stationary CI engines with a displacement of 30 l/cyl and above. Subsequently, EPA has made

this clear in the final rule. Al so, EPA notes that it has clarified that stationary non-emergency CI engines with a displacement of 30 l/cyl and above that are located in areas of Alaska not accessible by the Federal Aid Highway System (F AHS) are subject to the PM requirements in 60.4204(c)(4) that apply to owners and operators of stationary non-emergency CI engines greater than or equal to 30 l/cyl.

5.3 Comment : One commenter (53) asked that EPA r econsider how urban and rural areas of Alaska are defined. The commenter (53) acknowle dged the definition that is currently in place,

which defines rural areas as those areas not a ccessible by the FAHS. Th is definition has been used in Federal regulations for years, but based on recent changes that will require the transition to ultra low sulfur diesel (ULSD) for mobile source engines this year in rural areas, the commenter (53) requested that EPA evaluate whet her the definition remains appropriate. In the commenter’s (53) opinion, the cu rrent definition does not appropr iately consider impacts to small rural public utilities in Alaska that may be accessible by FAHS or not. These rural public25 utilities must deal with higher costs and have less financial resources than utilities in urban areas, plus are operated by staff with limited techni cal knowledge and training, the commenter (53) said. Consequently, drawing a line between sources subject to the rule or not by being accessible by FAHS would lead to inequi ties between small communities in Alaska who mostly all experience the same issues, according to comm enter 53. The commenter (53) added that a source being accessible by FAHS is a reasonable dete rmining factor, but is not an absolute. For example, according to the commenter (53), there are sources located along the Alaska Marine Highway System and other small remote source s along the highway system that must meet different requirements than those off the F AHS, however, their circumstances may not be different. Commenter 53 did not have a specif ic recommendation, but wanted EPA to look at possible alternatives for defining urban and rural sources in Alaska that would affect regulated stationary engines under the N SPS and NESHAP rules. During this evaluation, the commenter (53) asked that EPA take into account engine size and size of communities for instance, in determining which engines should not be subject to certain requirements of the rule, and indicated that it is willing to discuss this issue further with EPA.

Response : EPA does not believe that it is appropriate at this time to change how EPA delineates between areas of Alaska. The regulations current ly in place, which separate areas based on their accessibility to the FAHS, were developed under the original rule (71 FR 39154, July 11, 2006) and have been in place for regul ation of both mobile a nd stationary engines for several years. That rule distinguished accessible areas from non- accessible areas and this criterion is still the most reasonable distinguishing factor and EPA ther efore believes that it is still appropriate to maintain this definition in order to distinguish between stationary engines in Alaska. There are26 several places around the country that are small and economically disadvantaged, but only those areas of Alaska that are not readily accessible by the highway system are treated differently, in particular based on their isolation and the difficulty they have in accessing other areas. EPA also

notes that this issue ha s not been brought up before and was not part of the commenter’s request

letter. 3 Also, all the background information a nd rationale justifying the recommendations provided in the commenter’s request letter to distinguish remote Alaska from the rest of the country were based on this split based on accessibilit y. Many of the requirements in the rule are already in place and EPA has not heard of probl ems in these accessible areas. EPA notes that accessibility is interpreted to mean accessibil ity on a year-round basis, which includes t he portions of Alaska serviced by the contiguous road system, and portions of the Alaska Marine Highway System with regular drive-on, drive- off vehicle service on ferries (e.g., Kodiak, Ketchikan, Juneau, Sitka, Haines, Skagway, Petersburg, Wrangell, Cordova). [see http://www.dec.state.ak.us/ai r/anpms/ulsd/ulsdtranplan.htm and http://www.dot.state.ak.us/amhs/ ] The commenter did not provide any specific

recommendations in terms of how it believes urba n and remote areas should be redefined and in the absence of clarity on what th e boundaries should be, there is no real basis at this time for the commenter’s request to make a change to the curr ent distinction. EPA con tinues to believe that

the distinction in treatment betw een engines in Alaska should be based on whether areas are on the FAHS system and is therefore not making any ch anges at this time to this criterion in the

final rule.

3 Letter from Alice Edwards, State of Alaska to Jaime Pagán, EPA. Alaska Comments on NSPS for Stationary Diesel Engines. October 31, 2008.27 5.4 Comment : One commenter (53) expressed concer n over the proposed requirements for small remote power plants in Alaska that would necess itate aftertreatment in order to meet the PM limits. The commenter (53) pointed out that EP A recognized that select ive catalytic reduction (SCR) is not justified in rural Alaska. The co mmenter’s (53) concern regarding aftertreatment for PM is based on the majority of small rural power plans be ing un-staffed and the technical capability of staff is minimal and includes only basic maintenance tasks, including maintaining the oil, filter, belts and hoses. The commenter (53) said that engines that are equipped with aftertreatment like diesel partic ulate filters (DPF) and oxidation catalysts have automatic safety devices installed that will derate the engine in the event that the backpressure or temperature go beyond prescribed limits. Commenter 53 made the argument that should a prime power generator derate at a plant that was not staffe d, the engine would not maintain frequency and would trip off line. The engine would shutdown and power would be interrupted or unavailable to the community, the commenter (53) said, and should this happen during extreme temperatures, the life, health and safety of a community are at stake. Defeat devi ces are not permitted under EPA’s regulations for certified engines so the cons equence would be that th e only way an engine

could be restarted would be for a technician to fly to the pl ant and address the issue, the commenter (53) said. Considering transportation limitations in rural Alaska, especially during extreme cold weather at winter time, it could take several days for the techni cian to arrive at the site, commenter 53 noted. Becau se of the following reasons, the commenter (53) recommended that aftertreatment for reducing PM emissions not be required for small unmanned rural Alaska power plants:28  Power plant PM emissions in rural Alaska ar e substantially less than what EPA used for

baseline emissions in 1990 calculated from AP-42 information, which means the air is already cleaner than EPA’s estimation;

 The density of emissions in a rural community is normally lower than an urban area. Since the only diesel engine operating in a ru ral community is the one at the power plant, the magnitude of diesel PM emissions in a rural area is different than an urban one;

 Not requiring PM traps removes issues with high sulfur fuel (from used oil blending) contaminating aftertreatment;

 Reliable electric power is vital to life, health and safety; and

 The cost over the entire life span of PM afte rtreatment in rural Alaska is two to three times higher than EPA estimated for urban areas in the U.S. EPA used this rationale to exclude stationary engines in rural Alaska from numerical emission standards under the NESHAP and from meeting emission limits ba sed on the use of SCR under the NSPS.

Response : EPA disagrees with the commenter that PM limits that nece ssitate the use of aftertreatment like DPF should not be required at a ll for stationary CI engines located in remote

areas of Alaska. The need for PM control wa s in the commenter’s original request to EPA noting that PM is the most significant pollutant of concern in remote areas of Alaska. Stationary CI engines are often in very close proximity to the towns and the diesel PM emissions, which are highly toxic, can fall on the towns. Substantial health impacts are associated with diesel PM emissions and EPA does not believe it is appr opriate to reduce th e stringency of PM29 requirements in remote Alaska. EPA’ s Diesel Health Assessment Document 4 (Diesel HAD) classified exposure to diesel exhaust as “likel y to be carcinogenic to humans by inhalation” at environmental levels of exposure. Other agencies at the international, fede ral and state level have

come to similar conclusions. 5 The Diesel HAD concludes “that acute exposure to DE [diesel exhaust] has been associated w ith irritation of the eye, nose, and throat, respiratory symptoms (cough and phlegm), and neurophysiological sympto ms such as headache, lightheadedness, nausea, vomiting, and numbness or tingling of the extremities.” 6 There is also evidence of immunologic effects such as the exacerbation of allerg enic responses to known allergens and asthma-like symptoms. The commenter has not provided any evidence to support the claim that PM traps using

low sulfur fuel tend to cause shutdowns. These devices are going on unmanned units in numerous places, but there should be people in the towns who are in much closer proximity to the engines than the engines in remote loca tions across the United States. Regarding the concerns raised by the State of Alaska regard ing the feasibility and cost of installing and operating DPF in remote villages, EPA is providing additional time in the final rule before new stationary engines in remote ar eas of Alaska are required to meet PM standards that would require DPF. The final rule requ ires new engines in remote areas of Alaska to meet the more stringent PM standards and use ULSD beginning w ith 2014 model year engines. The use of DPF for new nonroad and stationary diesel engines in the United States will be phased in from 2011 to 2015. Waiting until there is more widespread experience with operati ng and maintaining DPF

4 Health Assessment Document for Diesel Engine Exhaust,’’ U.S. Environmental Protection Agency, 600/8– 90/057F, http://www.epa.gov/ttn/atw/ dieselfinal.pdf, May 2002. 5 A number of other agencies (National Institute for Occu pational Safety and Health, the International Agency for Research on Cancer, the World Health Organization, California EPA, and the U.S. Department of Health and Human Services) have made similar classifications regarding the diesel exhaust lung cancer hazard. 6 “Health Assessment Document for Diesel Engine Exhaust,” U.S. Environmental Protection Agency, 600/8– 90/057F, http://www.epa.gov/ttn/ atw/dieselfinal.pdf, May 2002, p. 9–9.30 would allow time for Alaska's concerns regarding the feasibility of maintaining DPF on engines in remote areas to be addressed. The type of engines most often used to power the remote villages were required by the original final N SPS to meet PM standards based on the use of DPF beginning with the 2011 or 2012 model year, depe nding on the engine size. Providing a delay until the 2014 model year for engines located in remote Alaskan villages would provide State with 2 to 3 years to gain expe rience with the operation of the c ontrols and develop the equipment infrastructure needed to properl y operate and maintain the DPF. In response to this comment, EPA consulted with vendors of DPF, who indica ted that the installation and maintenance costs for the systems are not as high as the es timates provided by the State of Alaska. 7 EPA recognizes that the blending of used oil into dies el fuel is a concern for engines equipped with DPF; however, EPA believes that given the restricti ons in the rule for used oil blending (no more than 1.75 percent of total fuel and no more than 2 00 ppm sulfur in the oil), the increase in sulfur caused by the blending should not be a significant concern for the operation of DPF-equipped engines.

5.5 Comment : One commenter (55) said that it supports the proposed revisions to 60.4216 of 40 CFR part 60, subpart IIII, a ffecting engines in Alaska.

Response : No response is needed.

5.6 Comment : One commenter (53) supported allowi ng used oil blending under the CI NSPS

and reiterated its concerns from 2008. The co mmenter (53) argued that used oil blending is

7 See memorandum titled “Summary of Calls with Vendors of Diesel Particulate Filters (DPF)” in docket EPA-HQOAR-2010-0295.31 important for rural Alaska facilities. According to the commenter (53), the used oil that is used for blending with diesel fuel does not come fr om outside sources, but comes from within the facility from the operation of the facility’s own engines. Being permitted to blend used oil for burning in the facility’s own engine is important and decreases risk s related to disposal and spills

in areas that have limited resources available to d eal with such costs, th e commenter (53) said. Blending also provides additional energy from an available resource and according to the commenter (53), a significant environmental concer n in rural Alaska is th e improper disposal of used oil. In most rural Alaska communities, there are no permitted used oil disposal facilities and the cost of exporting used oil is burdenso me and can be the same price or more than purchasing new oil, commenter 53 noted. Accord ing to the commenter ( 53), the Alaska Energy Authority has developed a system of used o il blending that is cost-effective, reliable, environmentally appropriate, and that is used by several power plants in rural Alaska. The commenter (53) recommended that used fuel bl ending be allowed in the rule at a maximum blend level of 1.75 percent; a level that the commenter (53) has dete rmined will keep fuel within the American Society for Testing and Materials specifications.

Response : EPA acknowledges the commenter’s concer n on used oil blending, but notes that there is nothing in the rule that prevents the use of used oil unle ss it has a sulfur level above 15 ppm. Nonetheless, EPA believes it is appropria te to provide an additi onal provision to allow a very limited percentage of used oil (no more than 1.75 percent) as the commenter proposed. EPA is also requiring that the motor oil used for blending have no more than 200 ppm sulfur. Used oil blending, under this provision and in gene ral, is permitted if the used oil is “on-spec,” i.e., it meets the on-specification levels and pr operties of 40 CFR 279.11. If the used oil does not32 meet these on-spec criteria the used oil would be considered a solid waste and subject to requirements under CAA section 129 for solid wa ste incineration units. The requirements for these units are in 40 CFR part 60, subpart CCCC.

6.0 Temporary, Replacement, and Marine Engines

6.1 Comment : Three commenters (37, 54 and 55) agre e with EPA’s treatment of temporary engines as not having to meet requirements be yond those for nonroad engines, and the proposed language in 60.4200(e) of 40 CFR part 60, subpa rt IIII, regarding temporary replacement engines. Commenter 55 suggested making the sa me change in 40 CFR part 60, subpart JJJJ. Three commenters (37, 54 and 55) indicated that while they are supportive of the proposed language in 60.4200(e) of 40 CFR pa rt 60, subpart IIII, regarding temporary replacement engines they do not entirely agree with EPA’s rationale provided in the preamble to the proposed rule at 75 FR 32616 and another commenter (31) al so does not agree with EPA’s rationale. Commenter 54 said the language in the preamble could lead to confusion. Specifically, commenter 54 indicated that the prea mble seems to incorrectly assume that any replacement engine is a stationa ry engine. Similarly, commenter 37 indicated that the language in the preamble to the proposed rule is conf using and inconsistent . Commenter 31 and 47 expressed similar concerns regarding EPA’s in terpretation. One commenter (37) recommended that EPA should clarify the language, in pa rticular EPA’s second paragraph. Equally,

commenters 31 and 49 indicated that some of the supporting rationale langua ge provided in the preamble to the proposed rule is overly broa d and with the provisi on in 60.4200(e) of the proposed CI NSPS could lead to mobile source engi nes being inadvertently treated as stationary33 sources. Commenter 31 asked that EPA rem ove 60.4200(e) from the CI NSPS or, as an alternative, modify what the commenter (31) believes to be overly broad language in the preamble, including “portable engines that repl ace existing stationary engines on a temporary basis are considered stationary engines” and add clarification to the language in the preamble on

this issue. Two commenters (31 and 49) provided an example of a situation where a portable generator is used temporarily when the primary ge nerator is not in service. Three commenters (31, 49 and 54) said that EPA has made it clear that a porta ble generator is (absent the

clarifications under the definition of a nonroad engine) a mobile source, not a stationary source and some commenters quoted the following lang uage from the final 2004 nonroad rule (69 FR 38979) where EPA stated:

“The final standards are based on our ev aluation of the differing technical issues presented by the two primary kinds of equipment in this category, mobile power generation equipment (generator sets) and mobile machinery.” The commenters (31, 49 and 54) recognize that the definition of a nonroad engines in 40 CFR 1068.30 places restrictions on using portable equipment for stationary purposes and cited 40 CFR 1068.30(2)(iii) of the defi nition of a nonroad engine: “(2) An internal combustion engi ne is not a nonroad engine if:

... (iii) the engine otherwise included in paragr aph (1)(iii) of this de finition remains or will

remain at a location for more than 12 consecuti ve months or a shorter period of time for an engine located at a seasonal sour ce. A location is any single site at a building, struct ure, facility, or installation. Any engine (or engines) that replaces an engine at a location and that is intended34 to perform the same or similar function as the en gine replaced will be included in calculating the consecutive time period. ” Commenters 49 and 54 indicated that they believe the consecutiv e period language is intended to capture replacement of portable eq uipment with portable equipment, not the replacement of stationary equipment. The comm enters (49 and 54) argued that the reference to “engine” in the underlined text in the above quot ed language refers to a “nonroad” engine. Further, the commenters (49 and 54) cited EPA statements from the June 17, 1994 preamble to 40 CFR part 89, which said: “A portable generator engine which functions as a pe rmanent back-up generator and which is replaced by a different engine (or engines) that performs the same function would be an example of engines covered by (2)( iii). In such a case, the cumula tive "residence” of time of both generators, including the time between removal of the original engine and installation of the replacement, would he counted toward th e consecutive residence time period.” The commenters’ (31, 49 and 54) point wa s that if the consec utive residence time calculation includes a permitted, non-portable stationa ry engine, as opposed to a portable engine operating as a permanent engine, orig inally contemplated as part of the existing stationary source older than 1 year, the commenters (49 and 54) said that the time will always be more than 12 months and any portable unit that replaces a perm anent stationary unit even temporarily, will be considered a stationary engine. In the commente r’s (49) opinion this in inaccurate and there is no meaning here. Commenter 49 also presented the example where an existing emergency generator is being replaced by another emergency generator, but that during construction and installation, the facility might bring in a portable generator in th e meantime during if ther e is a time period where35 neither the existing emergency generator nor the replacement emergency generator is operating. The portable generator may be on a trailer at the f acility, but is not at the exact same location as the existing emergency generator. The commenter (49) noted that the po rtable generator sitting on a trailer is clearly a nonroad e ngine because it is not replaci ng the existing unit and is not at the same location and the commenter (49) agrees that this portable unit should be treated identically to an engine brought to a site for less than 1 y ear for general maintenance or construction. Classifying the portable unit in th is manner is critical, the commenter (49) said because otherwise, if the engine is considered a stationary unit, it would be subjected to Prevention of Significant Deterioration (PSD) a nd minor stationary source construction permit requirements. According to the commenter (49), portable generato rs frequently exceed permitting thresholds on a potential to emit (PTE) basis, however the actual emissions from the unit is minimal to none. The commenter (49) ad ded that portable units do not quality as replacement units as defined in 40 CFR 51.166(b)(32) and consequently woul d be subject to the PTE test. The commenter (49) expressed that it does not agree with EPA treating any portable equipment that replaces a sta tionary unit to PSD and minor stationary source construction permitting requirements, even if the unit is tempor arily at the site for less than 12 months. The commenter (49) recommended that EPA require stationary source permitting only if a portable engine stays or will stay at the stationary lo cation for more than 12 consecutive months. The commenter (49) also asked that EPA either remove 60.4200(e) or revise the preamble discussion on this issue, particularly the statement: “P ortable engines that replace existing stationary engines on a temporary basis are considered sta tionary engines” and cl arify EPA’s intentions.

Commenter 55 said that it be lieves that a nonroad engine is a nonroad engine until it no longer meets the definition in 40 CFR 1068.30. Comm enter 55 indicated that it does not believe36 that a nonroad engine is consider ed a nonroad engine and a stationa ry engine, as discussed in the preamble to the proposed amendments. Commenter 47 asked that EPA clarify langua ge on page 32616 of the proposed preamble that discusses portable engines, specifically the langua ge in the third paragraph under the section C. The commenter (47) highlighted the language in the first three sentences of that paragraph to be most troublesome. The commenter (47) believ es that this language as written is confusing when it comes to the status of portable engines that temporarily replace stationary engines and argued that this could actually cause temporary portable engines to be restricted in some jurisdictions. The commenter (47) wanted EPA to specifically cl arify the language on this issue and that the same approach as taken when the CI NSPS was finalized in 2006 remains in effect. The commenter (47) indicated that it disagrees that portable engines that replace stationary engines temporarily should be tr eated as stationary engines, wh ich the commenter (47) said is inconsistent with EPA’s prior approach. Again, treating portable engines as such could lead to portable engines not be allowed to be used as temporary replacement units, the commenter (47) said, who stressed the importance and need for portable engines, highlighting the ability to quickly move a portable engine to replace a stationary engine th at has experienced a malfunction or is in need of repairs th at were not anticipated. The commenter (47) emphasized the significance of portable engines, wh ich are critical to support facil ity operations short term while the main, stationary engine is temporarily out of service. According to the commenter (47), there are several State and local agencies who have categorical pre-construction permitting exemptions for nonroad or portable engines, if the engi ne meets the definition in 40 CFR 1068.30 of a nonroad engine (excluding paragraph (2)(ii) of that definition), e.g., Massachusetts. The commenter (47) argued that if EPA considers temporary replacem ent engines stationary sources37 and subject to requirements under 40 CFR part 60, subpart IIII, State and local authorities may require pre-construction approval based on the e ngine being subject to NSPS (e.g., Colorado and Oklahoma). Also, the commenter (4 7) said that if such engines are considered stationary and regulated as such, it might be necessary for faci lities to acquire a State construction permit prior to operation. The permit approval process could take several months, th e commenter (47) said, which clearly would preclude the ability to use temporary, emergency replacement units. The commenter (47) does not believe that EPA needs to treat portable engines that temporarily replace stationary engines as stationary engines. The commenter (47) re commended that EPA at a minimum clarify that portable engines that repl ace stationary engines on a temporary basis that are undergoing bona fide maintenance and repair would not be consider ed stationary engines. In

situations where the maintenan ce and repair cannot be documen ted, the portable engine should be treated as a stationary engi ne and its emissions should be included in emission calculations, the commenter (47) asserted.

Response : EPA notes that this rulemaking does not change the definition of nonroad engine or stationary engine and is merely reiterating it s views on these longstanding definitions. EPA disagrees with the commenters’ statements that portable engines that replace existing stationary engines on a temporary basis should not be considered stationary engines. The definition of nonroad engine explicitly states that “Any engine (or engines) th at replaces an engine at a location and that is intended to perform the same or similar function as the engine replaced will be included in calculating the consecutive tim e period [for determining whether engines are nonroad or stationary].” See, e.g. 40 CFR 89.2 an d 1068.30. The import of this language is that all engines that are at a location performing the same or similar function would be considered38 stationary engines if the combined time period is greater than 1 year fo r a non-seasonal source. This is clear in the preamble to the rule that promulgate d this definition. The revised nonroad engine definition also in cludes a provision that if an engine is replaced by another engine w ithin the 12 month period, the replacement engine should be considered in calculating the consecutive time peri od. This provision is de signed to ensure that where an internal combustion engine is necessary for the operation of a st ationary facility, the replacement of one particular engine with a nother would not prevent the engines from being included as part of the stationa ry facility (59 FR pages 31305, 31311). Thus, all engines that perform the same or similar function at a location would be considered stationary if their combined re sidence time is greater than 1 year.

This is not inconsistent w ith the language in the pream ble to the 2004 nonroad engine rule. Certainly mobile generators sets, i.e., thos e that are not defined to be stationary, would be covered by that rule. This would include many port able engines, but not those excluded from the definition of nonroad engine in paragraph (2)(iii) of that definition. Inde ed, the reason why the stationary CI engine standards were coordinated with the nonroad engine regulations is because many of the same types of engines would be used in both nonroad and stationary applications. EPA notes that the language in the 2006 CI NS PS Response to Comment document is confusing in that it initially seems to be counter to the language regarding re placement engines in paragraph (2)(iii) of th e nonroad engine definition, but it th en caveats its initial statement by referencing that paragraph. To the extent the la nguage in the 2006 document is inconsistent with this Response to Comment document, the language in the preamble to the initial nonroad rule, and the language in the regulator y text, it should not be relied upon.39 The commenters’ view that the language in the definition refers onl y to replacement of one portable engine with anothe r is belied by the language in th e definition (“Any engine (or engines) that replaces an engine at a location and that is intended to perform the same or similar function as the engine re placed will be included,” emphasis added ) and in the preamble language quoted above. The distinction the commenter atte mpts to make is also illogical in that the distinction it makes between the engines bei ng replaced is not based on the criteria (e.g., residence time or the stationary nature of the replaced engine) found in the definition. In addition, the suggestion that word “engine” in the definition of “nonroad engine” should be interpreted to mean only nonroad engines is contra ry to the plain language of the definition and is also illogical, since the point of the definition is to define wh at engines are nonroad engines, as opposed to other types of engines, and restric ting the word “engine” to nonroad engine would defeat that purpose and would also involve circular logic. Nor doe s this interpretation mean that the residence time requirement will always result in engines being considered stationary engines, as in many instances (e.g., engine s brought in to perform a particul ar service like construction or maintenance or drilling) the residence time language defines whether the engi ne is stationary or

nonroad. However, EPA agrees with the views of co mmenters that note the replacement engine must be at the same location as the engine it is replacing to be included in the same residence time, which may in many cases address the conc erns of the commenters. EPA has revised the language of the preamble to adhere more closely to the language in the regulatory definition of nonroad engine.

Commenter 49 does not believe emissions from these engines should be included in the emissions for the stationary sour ce, but the entire purpose of defi ning these engines as stationary40 engines is to prevent sources from excluding th ese emissions (as well as the emissions of the engine they replace) in calcula ting emissions from the source, desp ite the fact that they clearly are tied to the permanent emissions profile of the source. The commenter does not explain why these engines would have potential-to-emit any great er than the engines they replace, unless they actually do emit more, in which case such emissions should be accounted for. It is not clear if the commenter is stating that ope rators would be required to a ccount for the emissions of both engines at the same time even if one is truly replacing the other tem porarily and they never operate at the same time. That issue is beyond th e scope of the NSPS. In any case the provisions of both this definition and those in 40 CFR part 51 have been in place for many years and were not changed in this rule.

6.2 Comment : Several commenters (37, 54, an d 55) provided their opinion and recommendations on how to treat stationary engi nes used in marine offshore settings. One commenter (54) said that marine engines shoul d not be subject to la nd-based standards and indicated support for revisions to allow the use of marine base d standards as opposed to NSPS for offshore platform installations. The comm enter (54) indicated th at these engines are normally nonroad engines that are subject to marine engine sta ndards. The engines remain a nonroad engine until it no longer meets the crite ria of the nonroad engine definition in 1068.30 and becomes instead a stationary engine, as defined in 40 CFR 60.4219 (CI NSPS) and 40 CFR 60.4248 (SI NSPS), according to the commenter (54). Further, the commenter (54) said that these criteria should apply if an engine replaces or acts as a stationary engine, or is on the platform for less than 1 year fo r general maintenance or constr uction activities. The commenter (54) said that if the marine engine is used in a stationary manner, the commenter (54) is41 supportive of language being added to indicate that stationary engine s in marine offshore settings may comply with applicable marine engine stan dards as opposed to the land-based standards. The commenter (54) asked that this language be added to both 40 CFR part 60, subparts IIII and

JJJJ. Two commenters (37 and 55) responded to EPA’s request for comment on the need for stationary engines in marine offshore settings to use engines meeting the marine engine standards, rather than land-based engine standa rds. Commenter 55 said that it supports using marine-based standards for offshore platform inst allations. The commenter (55) said that those engines are nonroad engines subject to marine-based standards unl ess the engines stay in one location on the platform for more than 12 mont hs. The commenter (55) believes that these criteria should apply if the engine replaces a stationary engine or is at the platform for less than 1 year for general maintenance or construction acti vities. In the event that the marine nonroad engine becomes a stationary engine, the additio n of language in 60.4200(e) or another section of 40 CFR part 60, subpart IIII indi cating stationary engines in marine offshore settings may comply with applicable marine engine standards rather than the land-based engine standards in 40 CFR part 60, subpart IIII. For consistency, this approach should also be applied to the SI NSPS (40 CFR part 60, subpart JJJJ) and th e NESHAP (40 CFR part 63, subpart ZZZZ). Commenter 37 said that it supports the use of either nonroad or mari ne certified engines for stationary engines on offshore platforms becau se it provides flexibility and advantages where space and weight limitations could lead to signif icant considerations. Furthermore, in the commenter’s (37) opinion, the difference betwee n emissions from marine and nonroad engines

should be of minimal concern because of th e remote location of offshore platforms.42 Response : EPA requested comment on the need for stationary engines in marine offshore settings to use engines meeting the marine engi ne standards, rather than land-based engine

standards. Based on comments rece ived on this issue, EPA agrees that it would be appropriate to allow stationary engines used in marine offshore se ttings to meet marine engine standards. EPA understands that engines used in these settings are generally cert ified to marine standards and that it may not be possible to know how an engine will be used throughout its life when it is first used. EPA does not see a need to require engines utilized in the same ma rine offshore setting to be certified to different standards based solely on the time an engine remains in one offshore location. It therefore is appropria te to require engines used in bot h mobile and stationary marine offshore applications to be able to meet the same standard.

7.0 Digester Gas Engines

7.1 Comment : One commenter (48) requested relief for stationary engines fueled by digester gas claiming that the emission standards applicable to these engines are hard to comply with. Moreover, the digester gas that is used in engines to create powe r is generated from wastewater treatment and contains methane, a potent greenhous e gas, the commenter (48) said. This gas can be used to power engines while reducing utility reliance on other fuel sources and decreasing greenhouse gas emissions, the commenter (48) ar gued and believes that utilities should be encouraged to operate engines on digester gas, as opposed to going with the option of purchasing power and wasting a valuable fuel source by flari ng the digester gas create d from the wastewater treatment process. Therefore, the commenter (4 8) asked that stationary engines that utilize digester gas fuel be exempt from the NSPS.43 Response : EPA contacted the commenter for furthe r information regarding this comment and

confirmed with the commenter that the comment pertains to both 40 CFR part 60, subpart IIII and subpart JJJJ. The commenter indicated that its members operate digester gas fueled engines that are both CI and SI engines, and according to the commenter, these engines would have difficulties meeting the NSPS emissions standards. What the commenter is requesting related to exempting digester gas engines that are SI engines is not in the scope of this rulemaking. This rulemaking only makes substantive changes to 40 CFR part 60, subpart IIII (CI NSPS) and minor changes to 40 CFR part 60, subpart JJJJ (SI NSPS) more for consistency purposes. EPA is not exploring issues that are unique to the SI NSPS at this time. The commenter did not provide any information to support the claim that digester ga s engines cannot meet the applicable emission standards. In addition, 60.4217 in 40 CFR subpart IIII allows owners/opera tors of engines using special fuels to petition the Administrator for alternative emission standards for the engines.

8.0 Test Methods

8.1 Comment : One commenter (37) said that the te st method for stationary engines with a displacement at or above 30 l/cyl needs to be changed from Method 5 to Method 5B or Method 17. The commenter (37) indicated that it has pr eviously submitted a letter to EPA describing its concerns with using Method 5 for these engines. The commenter (37) reiterated its position that Method 5 is inappropriate and that EPA should allow alternative methods for measuring PM. The main reason the commenter (37) believes Met hod 5 is not suitable is because it requires the use of glass fiber filters maintain ed at 120 degrees Celsius (°C). Th e method also requires that in44 sources that have sulfur dioxide (SO 2 ) or sulfur trioxide (SO 3 ) that the filter material be unreactive to these polluta nts and International Organization for Standardization (ISO) method 9096 2003 does not recommend glass fiber filter use where this reaction occurs. The commenter (37) went on to say that the temperature requ ired by Method 5 is generally much lower than normal exhaust temperatures from large displaceme nt engines. This nece ssitates cooling of the exhaust gas in order to use Method 5, the co mmenter (37) said, which would lead to the

formation of additional condensat ion particles that would affect the sampling results. The commenter (37) argued that the method would not yield reproducible results and recommended that due to inconsistencies, EPA should allow alternative methods. Commenter 37 recommended that EPA raise the PM sampling te mperature in Method 5 to a minimum of 160°C, which essentially means changing Method 5 to Met hod 5B, and also allow st ationary engines to

use Method 17 as an alternative.

Response : EPA disagrees with the comment that EPA Method 5 does not pr ovide accurate and precise measurements of PM. The statemen ts in EPA Method 5 and ISO 9096 2003 regarding

the selection of filtration media that are unreactive to SO 3 are intended to ensure that the proper filter media are used. When acceptable filter media are selected, including glass fiber filters that

are unreactive to SO 2 or SO 3 , EPA Method 5 has been shown to provide reproducible results irrespective of the filtration temperature chosen. EPA also disagrees that EP A Method 5 cannot achieve a filtr ation temperature of 120°C (250°F) since there are no procedures for coolin g the sample gas from the stack temperature to the required filtration temperatur e. EPA Method 5 is silent on the method for cooling the sample gas, as this is left to the discretion of the s ource test individual. Th e method employed depends45 upon the stack gas temperature, the required filtra tion temperature, and the equipment available

to the individual test contractor . In most situations, no specia l procedures are required since sufficient cooling is achieved by normal air expos ure of the probe and filter holder. Where filtration temperature is likely to exceed the method specified temperature, contractors have used specially constructed air cooled or water cool ed probes to achieve the proper temperature. Regarding the use of Method 5B or Method 17 as an alternative to Method 5, the mass of filterable PM emissions perhaps more than any ot her pollutant is defined by the test method and the associated sampling conditions. Filter temp erature is the primary driver of differences between results from different methods along with th e relative concentrations of constituents of the stack gas that condense at or above the fi lter temperature. For fossil fuel combustion products, there are ash particles that will be solid and collected at any practical sampling temperature. Any of the three methods will m easure the same mass of ash-derived particle emissions. The complexity comes because of some acid gases also in the stack exhaust, particularly sulfuric acid from oxidation of the sulfur in the fuel. These acid gases begin to condense at temperatures below 160° C more or less in proportion to the acid gas concentration.

That means that a method such as Method 5B with a filter temperature controlled to 160°C will collect less mass of these acid gas particles than will a Method 5 with a filter temperature controlled to 120°C. Method 17 prov ides for inserting the filter in the stack presenting an even more variable measurement. The practical st ack gas upper temperature limit for Method 17 is

about 160°C but the method can be used at much lower temperatures (until water droplets form in the stack). EPA cannot predict how results collected at different filter temperatures will compare for a particular source or between source s except that particulate samples collected at lower filter temperatures will produce higher mass emissions than samples collected with higher46 filter temperatures. EPA does not agree that it would be appropriate to allow the use of Method

5B or Method 17 as an alternative to Method 5 due to this difference in results, and lack of predictability regarding how particulate levels will change at different temperatures.

8.2 Comment : One commenter (37) noted that the J une 13, 2007, final NSPS for Electric Utility Steam Generating Units and Industrial-Commercial-Institutional Steam Generating Units specified the use of EPA Method 5 with a sample temperature of 160°C, and also allowed EPA

Method 17 for boilers.

Response : The commenter is correct that NSPS for Electric Utility Steam Generating Units and

Industrial-Commercial-Institutional Steam Generati ng Units allows the use of EPA Method 5 at 160°C (320°F). EPA Method 5 at 160°C is used fo r compliance since all test data used as the

basis of the numerical emissions limit in that NSPS were collected at 160°C.

8.3 Comment : One commenter (27) said that it agrees with EPA’s earlier response to previous comments regarding Method 5. The commenter (27) indicated that material deposited in the probe as sample gas cools from stack temper ature to 248 °F required by Method 5 will be recovered and weighed under the Method 5 normal procedures. Despite the commenter (27) noting this, it is concerned about another aspects of the method, i.e., PM emissions may still be in the vapor phase at temper atures of 248°F and the commen ter (27) recommends that EPA lower the probe and filter temperature to more accurately represent actual PM emissions. Alternatively, commenter 27 suggested that EPA re quire the use of the new “back half,” Other Test Method (OTM) 28 for measure PM emissions. Further, the commenter (27) noted that if47 emissions are found to be very low, Method 5I would be a more approp riate alternative than

Method 5 because it ensures a lo wer detection limit for PM colle cted from low concentration sources. The commenter (27) added that the ab ove temperature consider ations apply to Method 5I also. In the commenter’s (27) opinion, if in -stack sampling methods are chosen, i.e., Method 17, Method 201A or OTM 27, OTM 28 should also be sp ecified to assure that all PM that is

solid or aerosol at ambient te mperature will be quantified.

Response : EPA Method 5 does exclude PM which are vaporous at elevated temperatures, but

which condense to form fine PM at ambient temperatures. The addi tion of the recently promulgated revised Method 202 (which repl aced both the 1990 version of Method 202 and OTM 28) to Method 5 quantifies this additional PM. The maximum filtration temperature for Method 202 is 30°C (85°F) and would be expected to retain a greater mass that any of the previously mentioned test methods. While each of these test methods will quantify a different mass of PM, when performed consistently within their respective specif ications, each method provides for precise mass emissions measurements.

9.0 Definitions

9.1 Reconstruction

9.1.1 Comment : Several commenters (26, 32, 37, 39, 40, 43, 46, 50, 53, and 55) are concerned with the proposed definition of reconstruction. According to Commenter 55, this and other terms (date of manufacture and installed) have been in cluded by EPA in order to redesignate stationary engines currently not su bject to the rule to become subj ect to NSPS after conducting routine48 maintenance, repair, rework, and overhaul. Se veral commenters (43, 46, 50, and 55) stated that EPA has not provided sufficient rationale for adding this new defin ition and the term is significantly different from other NSPS definitions and applicability determinations regarding reconstruction. One commenter (55) also stated that the definition is inconsistent with the

definition used in the NESHAP. Two commenters (43 and 55) said that the proposed revisions add problems and commenter 55 is of the opi nion that the rulemaking adds burden and implementation issues to the regulated commun ity beyond currently unresolved issues, which the commenter (55) said it has previo usly brought to EPA’s attention. 8 One commenter (50) said that if the defin ition is finalized as proposed the outcome for the commenter’s (50) industry is that most existing natural gas engines will trigger reconstruction at every overhaul. Subsequently, nearly all these engine s would transition from an existing engine to being subjec t to 40 CFR part 60, subpart JJJJ, in an infeasible time frame. As discussed in comment 9.2.1, the commenter (50) fu rther indicated that this would also result in (due to the removal of the crankshaft la nguage) these engines havi ng to meet new engine standards; levels that these older engines were not designed to achieve and some would be incapable of meeting. The commenter (50) asserted that the proposal will have substantial cost impacts that necessitate a cost-ben efit analysis to suppor t the justification for basically instituting a new rulemaking for existing engines. Two commenters (46 and 50) sa id that the proposed defini tion excludes the cost of fundamental components from the fixed capital cost s, such as the engineering costs, construction and site installation and startup costs, and the costs associated with auxiliary components that

service or that ar e critical to the engine’s operation. Commenter 55 made similar claims. One

8 Letter from Stephanie R. Meadows, Senior Policy Adviso r, American Petroleum Institute, to Michael Horowitz, Office of General Counsel, U.S. Environmental Protection Agency. March 10, 2010.49 commenter (50) indicated that th ere are several examples of pr ecedent that demonstrates the components that should be included in fixed capital costs. The commenter (50) cited to several EPA applicability determinations (e.g., Control #9800085 dated 5/11/98 and Control #0200048 dated 9/3/99), pointed out the language in EP A’s December 16, 1975 preamble to the NSPS, and other applicability determinations EPA ha s conducted, which all demonstrate that key components necessary for engine operation shoul d be included in the fixed capital cost calculation. Again, the commente r (50) said that it believes EPA has failed completely in providing the public justification for changing the definition, which EPA is legally obligated to

do. Commenter 43 asserted that it strongly obj ects any exclusion of components necessary for engine operation in the reconstruction determin ation and stressed that such components like the cooling system, should be included even though it is not connected to th e engine like it is for smaller engines. Two commenters (43 and 55) re quested that EPA use the defi nition of reconstruction that is currently in 40 CFR 60.15(b) in the final rule s and asked that the proposed new definition of

“reconstruct” in 60.4219 and 60.4248 not be included in the final rules. According to commenter 55, reconstruction under 40 CFR 60.15(b) differs substantively from the proposed definition under 60.4219 and 60.4248, including unjustifiably desi gnating many rebuilt engines, that would have remained “existing”, as “reconstructed” (and therefore subject to new emission limits). Likewise, commenter 46 requested that EPA main tain the definitions in 40 CFR 60.15(b) and 40 CFR 60.15(c), for reconstruction and fixed capital co st, respectively, in the final SI NSPS. The costs of the compressor and any driven equipmen t and other components not needed to operate the engine should be excluded from the term fi xed capital cost, the co mmenter (46) said.50 Similarly, commenter 50 asked that EPA retain the reconstruction de finition from 40 CFR 60.15, but limit the applicability to stationa ry SI engines as follows in 60.4248: “Reconstruct means to replace or refurbish components of an existing engine to such an extent that the fixed capital cost of the new and refurbished components exceeds 50 percent of the fixed capital cost of a comparable entirely ne w facility. The fixed capital cost of the new and refurbished components and the fixed capital co sts of the comparable new facility shall not include the cost of replacing components driven by the engine, such as pumps, generators and compressors, or other components not connected to the engine or not essential for engine operation. For purposes of reconstr uction of SI engines, an existi ng stationary engine is defined as including those components necessary for engi ne operation and those components mounted to or within the cylinder block, the engine hous ings, and engine mounted components. Those components that relate to both th e engine and the driven equipmen t shall only be included in the fixed capital cost by the pro -rata amount the directly re lates to the engine.” The commenter (50) argued that stationary industrial engines are intended to be overhauled multiple times during their useful lif e through the replacement of certain parts that experience normal wear and tear, and that this standard overhaul process does not mean that it would be feasible for the engine to meet NS PS emission standards because the replacement of the components during the normal overhaul proce ss does not typically al ter the technological capabilities of the engine.

If EPA includes the definition of “reconstruct” in the fina l rules, commenters 43, 46, 50,

and 55 recommended that the definition be revised to make sure that all engine components are

included in the reconstruction determination that are necessary for engi ne operation. According to commenter 55, the proposed definition seeks to restrict the existing stationary engine51 components to a narrow prescribed list of incl uded and excluded parts. The commenter (55) strongly recommends relying on the 40 CFR General Pr ovisions definition and associated

determinations. Two commenters (43 and 55) sa id that the definition deviat es from EPA’s Applicability Determination Index (ADI) and Control Cost Ma nual, which indicate which costs should be included in conducting the recons truction cost analysis. Commenter 55 claimed that EPA’s historical definition of the fixed capital costs asso ciated with reconstruction includes peripheral, indirect costs and all depreciable components; whereas the proposed definition is more narrowly

defined. Commenter 55 asserted that this na rrow definition shows a c ontinued reliance by EPA on a mobile source or small, packaged engine desi gn, and that this paradigm is inappropriate for many stationary units affected by the rule. Furt hermore, the commenter (55) stated that the proposed definition would also inappropriately and unjustifiably eliminate the provision for demonstrating technological and economic feasibility of the r econstructed source meeting the applicable standard(s).

Commenter 55 believes that the term “recons truct” is not well defined and is not technically supported by EPA. If the term is included in the final rules then EPA should explain why it is taking a different position compared to previously when in response to comments on

the 2008 SI NSPS EPA said that the General Prov isions definitions are appropriate, commenter 55 said. Additionally, EPA should provide the ba sis and rationale for the definition and also present the cost and benefit of finalizing this definition.

If the definition is included in the final ru le, commenter 55 requested that the definition only affect reconstruction that began after the ef fective date of the final rule. The commenter (55) does not believe that retros pective review is justified and should not be required. Plus, the52 commenter (55) asked that EPA also define related terms that are us ed in the definition in order to prevent confusion and to ensu re clarity. For example, the te rms “refurbish” and “refurbished components” are not defined in the proposal, the commenter (55) said, and additionally, if these terms are used in the final rule, they need to be distinguished from other terms like routine preventative maintenance, repair, ov erhaul, replacement and rework. Commenter 37 supports a specific definition fo r “reconstruction,” but is concerned about EPA’s change in the manufacturing date criteria for reconstructed engines. The commenter (37) had previously submitted comments on the original proposed SI NSPS that a specific definition for “reconstruction” was needed and the commenter ( 37) said that it had in dicated at that time

that the current definition in the General Prov isions of 40 CFR part 60 was outdated and not suitable for stationary engines and that some of the terms in the General Provisions are not appropriate for stationary engine s. The commenter (37) indicated that it is generally supportive

of the definition of “reconstructi on” that EPA has proposed, but be lieves that when determining the cost to reconstruct an engine, the costs for ancillary components such as external cooling or fuel supply should be included in the total ne w engine costs because such components are necessary to make sure the prope r fit and function of the new engi ne. Other commenters (46 and 50) echoed these comments asserting that the cost s for the operation of a comparable new facility

should include the costs associated with constr uction, engineering, and equipment necessary for operation of the facility, which w ould be consistent with the hist orical approach EPA has taken. EPA should explicitly recognize commenter 46 said that the costs of the cooler, skid, wiring and other equipment necessary for the engine to opera te should be included in the reconstruction calculation on a pro-rata basis. The commenter (46) additiona lly recommended that EPA add a definition for “comparable entirely new facility” to the definition of “reconstruct” in order to53 make sure that the reconstruction cost denominat or includes the cost of all components necessary for the engine to operate. Similarly, commenter 50 said that EPA should clarify the meaning of comparable entirely new facility and in the commenter’s (50) opinion the term should include only the engine and the relevant portions of comp onents that are necessary for engine operation. According to the commenter (37), such com ponents would be necessary if an owner was to purchase and install a new engine and ther efore should be included in the reconstruction determination. Similarly, commenter 40 said that the costs of a comparable new engine have not been properly defined and a new engine cannot simply with dropped in place, but may require different components than the old engine and should also in clude facility modifications necessary in order to acc ommodate the new engine. Another commenter (39) also agreed with previous commenters that anc illary components should be incl uded in the determination. Commenter 40 specifically recommended that EP A incorporate the following language into the

definition in 60.4219 and 60.4248: “For the purposes of reconstruction, the cost s of a comparable new stationary engine include those components mounted to or within the cylinder block, the engine housings, engine mounted components, ancillary components and fac ility modifications necessary to allow a new engine to fit and function in th e existing engine’s application.” One commenter (39) asked what is supposed to be included in the fixed capital cost determination, and specifically wanted to know what rates should be used in calculating the total

labor costs because there is a wide variation. Co mmenter 39 recommended that if labor is part of the fixed capital cost then EPA should define th e cost of labor and suggested that EPA specify

that sources must use the Fede ral Government minimum wage.54 The commenter (37) also said that EPA should also include the techno logical criteria, in

addition to the cost criteria in the definition of reconstruction in the final rule for stationary CI and SI engines that was part of the original definition of reco nstruction. The commenter (37) argued that even though a source exceeds the 50 percent capital cost threshold, it may be technologically and economically infeasible to meet the emission standards for new engines. Commenters 46 and 50 similarly expressed that th e technical and economical feasibility criteria should be put back into the definition of r econstruction. These are key components of the concept of reconstruction included in the orig inal rule, the commenter (50) said, which is something that prevents owners fr om prematurely retiring engines pr ior to the end of their useful life because they cannot meet the standards for ne w engines in an economic way. To this point, EPA has always included the technical and economi cal criteria in the rec onstruction analysis and EPA is legally required to e xplain the rationale for this re gulatory decision through data, analysis, and demonstrably rational decision-making. Moto r Vehicle Manufacturers Ass'n v. State Farm Mutual Insurance Co. , 463 U.S. 29, 43 (1983).

Commenters 37 and 40 said that EPA should in the final CI and SI NSPS include the criteria currently in 40 CFR 60.15 when determin ing reconstruction that takes into account the

technical and economical feas ibility of meeting the sta ndards in those two parts. Similarly, commenter 53 said that the proposed definition of reconstruct is a departure from how EPA typically defines the term in the General Provisions (40 CFR 60.15(b)), which includes language regarding the te chnical and economical feasibility of meet the standards in 40 CFR 60.15(b)(2). As other commenters have not ed, commenter 53 also does not believe that EPA has adequately explained the reasons for pr oposing a different rec onstruction provision. The commenter (53) recommended th at EPA provide an explanation for this and describe why it55 believes the rule should not use the definition from the General Provisi ons. Further, the commenter (53) believes that it is not feasible for existing recons tructed engines to meet Tier 4 standards without applying retrofit add-on control technologies. As it relates to remote rural areas of Alaska, the cost, complexity and risk of utilizing these contro l technologies on prime power plants are not justified c onsidering the minimal PM reducti on that would be achieved, in the commenter’s (53) opinion. One commenter (26) asked that EPA clarify the requirements that apply to reconstructed engines. Specifically, the commen ter (26) believes that the language in II.F. of the preamble to the proposed rule that states “EPA is also pr oposing to add provisions to the NSPS that require reconstructed engines to meet the emissions standards for the model year in which the reconstruction occurs if the reconstructed engi ne meets any of...” and the language in 60.4201(f) and 60.4202(g) that states “Notwith standing the requirements in [the above paragraphs] of this section, stationary CI internal combustion en gine manufacturers are not required to certify reconstructed engines; however they may elect to do so” appear to be conflicting. The commenter (26) asked that EPA clarify if rec onstructed engines are re quired to meet emission standards. In an attempt to clarify the requi rements for reconstructed engines, the commenter (26) suggested that EPA include specific sections with the requirements for reconstructed engines to make it clear what applies to these engines. Commenter 43 expressed that it could not pr ovide substantive comments on this issue particularly as it relates to suggesting specifi c changes to the definition because it does not

understand EPA’s intent with the proposed changes. If EPA iden tifies the goals in proposing revisions affecting the reconstruc tion determination process, the commenter (43) said it could provide additional comment s and recommendations.56 Response : EPA proposed to add a definition of “rec onstruct” to the CI and SI NSPS as an attempt to clarify the meaning of reconstruc tion. EPA’s objective with the proposal was to provide a more specific definiti on applicable to sta tionary engines rather than the broader definition provided in the General Provisions of 40 CFR part 60. The proposed definition was intended to clarify how to c onduct the reconstruction analysis by specifically proposing to

include a definition that would be applicable to stationary engines subject to NSPS. EPA believed that providing a specific definition applicable only to stationary engines would be beneficial by bringing cl arity to how reconstruction is dete rmined in the stationary engine setting. EPA did not expect the proposed change to be controversial, nor di d EPA anticipate that the proposed change would cause such significant concern among affected sources. However, as illustrated in the summary of comments on this issue, several affected stakeholders strongly opposed EPA’s suggested changes to the histori cal definition of reconstruction. Based on the extensive concerns provided by commenters and subsequent information EPA has received from stakeholders after the proposal, EPA determined th at it is appropriate to not include the proposed

definition of “reconstruct” in the final rule. Instead, EPA is finalizing the rule using the

definition of “reconstruction” from the Genera l Provisions of 40 CFR part 60. Again, EPA intended to provide more guidance than what was originally provided in the rule on reconstruction; however, it is nearly impossible to capture all pot ential situations in a definition. EPA believes it is appropriate to continue to rely on the definition in 40 CFR 60.15. Therefore, EPA is not finalizing the proposed definition of “reconstruct.”57 9.1.2 Comment : Two commenters (37 and 40) said th at EPA should indicate which parts of 60.15 of the General Provisions in 40 CFR pa rt 60 apply to stationary engines.

Response : EPA is not finalizing the proposed definition of “reconstr uct,” but is instead pointing

to 40 CFR 60.15 for the definition of “reconstruction.” Therefore, it is not necessary to indicate in Table 8 of 40 CFR part 60 subpart IIII and Ta ble 3 of 40 CFR part 60 subpart JJJJ which parts of the General Provisions of 40 CFR part 60 apply, because the entire part applies.

9.1.3 Comment : One commenter (26) suggested th at there may be a typo in 60.4219 and 60.4248 of the proposed rule language and asked if the text “external cooling for fuel supply” should be replaced with “extern al cooling or fuel supply.”

Response : The language the commenter is referring to was in the proposed definition of “reconstruct.” EPA is not including this definitio n in the final rule, but is pointing to 40 CFR

60.15 for the definition of “reconstruction.”

9.2 Date of Manufacture

9.2.1 Comment : A number of commenters (26, 31, 32, 37, 40, 43, 46, 50, and 55) took issue

with the criteria in the definition of the “date of manufacture” and asked th at the definition either

be removed or revised.

Commenters 43 and 55 indicated that the cr iteria in the definition are flawed and inconsistent with previous defi nitions of reconstruction. Commen ter 55 stated that it does not58 understand EPA’s motivation or objectives for the significant revisions refl ected in the proposed definition of manufacture date, and therefore co uld not offer detailed comments to improve EPA’s proposal at this time. Co mmenters 46 and 50 said that EP A has not provided a reasonable explanation for the definition e ither. According to commenter 50, EPA has totally failed in meeting its legal obligation to justify applying new engine standards to reconstructed engines and contradicts the original SI NSPS, where the commenter (50) cited text indicating that EPA recognized the need for different standards fo r certain reconstructed engines. Several commenters (32, 39, 43, 46, 50, and 55) are of the opinion that it is not appropr iate to include the removal of the crankshaft as criteria for designa ting an engine being subject to new standards. This component is frequently removed duri ng inspection and mainte nance, according to commenters 32, 39, 46, and 50, who suggested that th e criteria related to the crankshaft be removed entirely. According to commenter 55, removal of the crankshaft is sometimes necessary to access components, but this should not constitute replacement. Commenter 39 asked that the replacement of the crankshaft be included in the fixed capital cost of reconstruction. According to commenter 39, the crankshaft does not have an effect on the engine’s emissions . Further, commenter 39 expre ssed that if the definition is finalized as proposed, it could le ad to rebuilding engines properly being impossible due to the increase in costs. It could certainly lead to a rebuilding process that is lesser quality where the crankshaft is not inspected and new bearings are simply installe d without removal and inspection of the components, the commenter (39) said. Ac cording to the commente r (39), there would be enforceability issues as well because during an inspection it would not be possible to determine

whether the crankshaft had been removed or not.59 At a minimum, commenter 32 recommended that EPA at least allow the removal and reassembly of the original engine crankshaft. Similarly, commenter 43 said that at a minimum, EPA should indicate that repla cement of the original cranksha ft would trigger a new engine classification, not simply the removal of the cr ankshaft. Also, the definition of “date of

manufacture” does not consider the feasibility assessment of 40 CFR 60.15(b)(2), the commenter (55) said. EPA’s proposed amendments would lik ely require engine replacement in some cases because retrofit control to achieve new engine standards may not be feasible, according to

commenter 55. Commenter 55 said that the proposed definition is an important issue because it could have costly implications with little or no benefit, since emission standards may not be achievable (for reconstructed engines categorized as new based on the redefined manufacture date). One commenter (37) opposes the definition of the “Date of Manufacture” and said that it has significant concerns with the definition. The commenter (37) said that removing the

crankshaft alone should not tri gger the need to meet new engi ne standards. According to commenter 37, a relatively new engine might need th e crankshaft to be removed or replaced if it experiences a main bearing failure, but the engine might not need other extensive reconstruction procedures in this case and subsequently the commenter (37) does not believe added modifications or engine replacement necessary to meet new engine standards would be justified

in such a situation. Commenters 37 and 46 do not believe that the removal of the serial number from the engine should necessitate the need to comply with new engine standards. That provision could restrict the current practical and effective remanufacturing of engines for stationary purposes, according to commenter 37. One commenter (50) said that the proposed changes to the date of manufacture definition co nstitute significant concern for industry because60 of the cost and operational impacts, plus regula tory confusion the commenter (50) believes the changes create. Based on the criteria for assigni ng a new date of manufacture, the commenter (50) argued the possibility that some existing engines may become obsolete due to the 1 g/HP-hr

NO x emission limit, which for lean burn engines may not be achievable. The commenter (50) supported this argument by indicatin g that lean burn engines cannot use non-selective catalytic reduction (NSCR) technology, which reduces NO x emissions and would theoretically make it feasible to reach a 1.0 g/HP-h r limit, because of the excess oxygen in the exhaust. The technology that is applicable to lean burn engines is oxidation catalyst, but the technology does

not reduce NO x , the commenter said (50). Therefore, lean burn engines, which typically emit around 1.5 to 2.0 g/HP-hr of NO x would become unusable if it receives a new date of manufacture, according to commenter 50. Further, the commenter (50) claimed that this would lead to rich burn engines replac ing lean burn engines because of rich burn engines are capable of reducing NO x emissions by NSCR. In the commente r’s (50) opinion, lean burn engines are inherently lower emitting, more fuel efficient and emissions are stable. For example, in terms of efficiency, the commenter (50) indicated that a rich burn engine ut ilized about 6,220 million British Thermal Unit per year more of fuel than a lean burn engine that was similarly sized.

Commenter 46 indicated that the serial num ber could be inadvertently be knocked off during transportation or use, and as ked that it also not be included as a criteria in the final rule. The commenter (46) indicated that it believes th at if EPA finalizes a different definition of reconstruct, as previously suggest ed by the commenter (46), that th e issue concerning the date of manufacture definition is gene rally resolved since the date of manufacture definition incorporates the definition of reconstruct. Again, the commenter (46) emphasized the importance of not including the re moval of the crankshaft and the reference to the serial number61 because those two components do not indicate that an engine has undergone modification at the

end of its useful life nor to the degree that the engine can tec hnically and economically meet the new engine standard. Commen ter 46 recommended that EPA ma ke the following revisions to the proposed definition of date of manufacture in the final rule:

“Date of manufacture means one of the following things: (1) For freshly manufactured engines and modi fied engines, date of manufacture means the date the engine is originally produced. (2) For reconstructed engines, date of manufacture mean s the date the engine was originally produced, except as specified in paragraph (3) of this definition. (3) Reconstructed engines are assigned a new date of manufacture if the c rankshaft is removed as part of the reconstruction or if the fixed capital cost of the new and refurbished components exceeds 75 percent of the fixed capital cost of a comparable entirely new facility engine (see the definition of “reconstr uct”). An engine that is produced from a previously used engine block does not retain the da te of manufacture of the engine in which the engine block was prev iously used if the engine serial number was removed (or the engine otherwise lo ses its identity), or the engine is produced using all new components except for the engine block. In all these cases, th e date of manufacture

is the date of reconstruction or the da te the new engine is produced.” One commenter (50) said that the automatic trigger of 75 percent in the fixed capital cost of a comparable new engine will most likely ma ke lean burn engines obs olete and subsequently requiring it being replaced by a rich burn engine. The commente r (50) indicated that if EPA retains the automatic 75 percent trigger in the defi nition of date of manufac ture in the final rule, the commenter (50) asked that EPA specify that if reconstructed facilities must meet the engine62 standard for existing engines in 60.4233(f) and not the new engine standard, claiming that this approach would meet the economically and t echnically feasible re gulatory standard. Commenter 50 recommended a very similar de finition, except that the commenter (50) suggested that paragraph (3) of th e definition be revised to read: “An engine that is produced from a previously used engine block does not retain the date

of manufacture of the en gine in which the engine block was previously used if the engine is produced using all new components except for the engine block.”

Commenters 43 and 55 recommended a different modified definition, with the following changes to paragraph (3) of the Date of Manufacture definition: (3) Reconstructed engines are assigned a new da te of manufacture if the crankshaft is removed as part of the reconstruction or if the fixed capital cost of the new and refurbished components exceeds 75 percent of the fixed capital cost of a comparable new engine (see the definition of “reconstruct”). An engine that is produced from a previously used engine block

does not retain the date of manu facture of the engine in which the engine block was previously used if the engine serial number was removed (or the engine otherw ise loses its identity), or the engine is produced using all new components except for the engine block. In all these cases, the

date of manufacture is the date of reconstructio n or the date the new engine is produced.”

Commenters 43 and 55 asked that if EPA does not remove the crankshaft criteria that EPA at least modify the criteria to specify that a new date of manufact ure is triggered if the crankshaft is replaced (not rem oved). Commenter 55 also recomme nds that the following text be replaced with simply “the date the engine is placed into service fo llowing reconstruction:” “An engine that is produced from a previously used engine block does not retain the date

of manufacture of th e engine in which the engine block was previously used if the engine serial63 number was removed (or the engine otherwise loses its identity), or the engine is produced using all new components except for the engine block. In all these cases, the date of manufacture is the

date of reconstruction or the date the new engine is produced.” According to the commenter (37), those engines are normally built from major components from failed or worn-out engines. The failed or worn-out engines are sent as cores to the engine remanufacturer, according to the comme nter (37), in exchange for a remanufactured engine. In the process, the used engine lose s its identity and become s loose parts, and the remanufacturer determines which parts can be re-used, according to the commenter (37). A mixture of new and re-useable components is us ed in assembling a remanufactured engine and unique serial numbers are assigned with no corre lation to the original engines, commenter 37 said. The entire process provides end-users with cost-effective options the replaces that need of rebuilding engines in place or in a repair shop, the commenter (37) said. The commenter is of the opinion that using the removal of the serial number as a criterion alone to comply with new engine standards would lead to an increase in th e number of engine rebu ilds performed in lessstructured facilities. The commenter (37) al so expressed that it doe s not concur with the requirement that a relatively new engine needi ng extensive repairs should not need to comply with new engine standards. The commenter (37) said that as it previously recommended, consideration should be given to take into account the age of th e engine. It was recommended by the commenter (37) that reconstr uction should not be triggered unl ess the existing engine is at least 15 years old compared to the current model year. The commenter (37) believes that a 15- year threshold would be appropria te as one of the factors in de termining if compliance with new engine standards is required. Commenter 37 also indicated that there is a precedent for the 15- year threshold in the replacement engine provisions in 40 CFR 60.4210(i). The commenter (37)64 further argued EPA’s proposed definition cl aiming that it would impose requirements beyond those required for nonroad and marine engine th at are reconstructed and remanufactured. The commenter (37) noted that the definition proposed would lead to a separate and new set of requirements for stationary engines only that are refurbished or remanufactured, that would change current industry practi ce by altering the date of manu facture and consequently the emission limits that apply for a small group of su ch engines. The commenter (37) argued that since EPA has followed mobile and marine regula tions in areas of emission standards, test methods and other requirements, it is not correct or appropriate to apply different and more stringent requirements on one subset of stationary engines, i.e., reconstructed engines. Instead, the commenter (37) recommended that EPA adopt the following definition in the final rules: “Reconstructed engines are assigne d a new date of manufacture if the engine is more than 15 years old relative to the current model year and the fixed capital cost of the new and refurbished components exceeds 75 percent of the fi xed capital cost of a comparable new engine (see the definition of reconstruct) . For reconstructed engines mee ting the above criteria, the date

of manufacture is the date that reconstruction is commenced.” Commenter 40 echoed commenter 37’s points on this matter (commenter 40 also concurs with all of commenter 37’s comments), and specifically recommende d that EPA remove paragraph (3) of the proposed de finition of the date of manufactu re and apply the reconstruction specific emission limits that are already in the CI and SI NSPS, which the commenter (40) stated already adequately consider the economically an d technically feasible opportunities for updating older engines. Alternatively, if EPA does not revi se the definition as suggested and the criteria that require reconstructed engine s to meet the latest standards are retained, the commenter (40) expressed EPA should revise the current propose d criteria, including changing the crankshaft65 criteria to when it is replaced or refurbished as part of reconstruction. Consistent with prior commenters, the commenter (40) does not believe the crankshaft is an appropriate trigger because it is routinely removed for inspection an d possibly replaced if n ecessary. Commenter 40

said that EPA should make sure that in the de finition, remanufacturing is treated consistently with other rebuilding practices. In the commenter’s (40) opi nion, replacing or refurbishing crankshafts would only be appropria te triggers if the definition of reconstruction is revised as commenter 40 recommended in comment 9.1.1. Also, the proposed trigger related to the 75 percent fixed capital cost in paragraph (3) of th e proposed definition of da te of manufacture is only acceptable if the definition of reconstruction is revised acco rding to the commenter’s (40) recommendation in comment 9.1.1. Moreover, the co mmenter (40) said that the language in paragraph (3) of the definition of date of manufacture related to an engine produced from a previously used engine block is completely inconsistent with EPA’s earlier conclusions regarding remanufactured engines as discusse d in comment 9.1.1 and this language should be removed, the commenter (40) expressed. Finall y, commenter 40 indicated that a new trigger should be included in the provisi ons that define the date of manufacture, consistent with

comments from commenter 37 that specify that new emission st andards should not be required for rebuilt engines unless they ar e at least 15 years old. The comm enter (40) pointed to similar provision currently in 40 CFR 60.4210(j). One commenter (31) believes that the proposed definition of date of manufacture places significant burden on reconstructed engines and said that the criteria in the proposed definition seem arbitrary (e.g., the removal of the crankshaft ) and trigger emission st andards that would be applicable in the year the rec onstruction occurs. The commenter (31) argued that EPA has not sufficiently discussed the justification for revisi ng the requirements for reconstructed engines66 and asked that EPA explain the basis and intent for this for the final rule. Alternatively, EPA should remove the elements of proposal that s upersede the definition of reconstruction in the General Provisions of 40 CFR part 60, commenter 31 said. One commenter (39) indicated that it does not agree with the langua ge in the date of

manufacture definition that says “the reconstructed engine cons ists of a previously used engine block with all new components.” The commenter (39) said that there are instances when an engine is damaged to the point where a replacem ent block (and other necessary components) is necessary in order for the engine to become operational again. When this occurs, the serial number from the replacement block is kept and the engine is rebuilt according to the arrangement number of the origin al engine. If the definition remains as proposed, this means that the cost to build an engi ne utilizing a used block and new components would exceed the 75 percent capital cost in the definition, accordi ng to commenter 39. The commenter (39) added that it is the arrangement number that determines the emissions of the e ngine, which specifies the components that are used to build the engine (e .g., pistons, turbocharger , injectors, etc.) and stressed that the arrangement number is a more appropriate indicator as to what the engine is rather than the serial number. Consequentl y, the commenter (39) recommended that the above quoted phrase be eliminated from the rule and th e leave the 75 percent cost threshold as the

criteria. In addition, two commenter (26, 39) pointed out that in the pream ble the capital cost threshold is 50 percent, while on page 32627 of the FR notice of the regulation (and on page 32630 of the FR notice), th e capital cost threshold is 75 percent. Commenters 32 and 39 said

that the threshold indi cated in the preamble on page 32619 s hould be increased from 50 percent67 to 75 percent because of the significant cost of many replacement engines, commenter 32 added. According to the commenter (32), replacem ent engines can cost more than $50,000.

Commenter 55 contends that if EPA retains the new definitions of reconstruction and date of manufacture, applicabil ity should not be retrospective – that is, previous reconstruction determinations relying on definitions in 40 CF R 60.15 should not be required to revisit or reevaluate previous determinations.

Response : As with EPA’s proposed definition of “rec onstruct,” the proposal to add a definition for the “date of manufacture” led to a significant c oncern with affected stakeholders as reflected in this comment summary. Commenters were generally not opposed to having a definition for the “date of manufacture,” but were against some of the criteria used in the proposed definition.

Based on the comments related to removal of the crankshaft, EPA agrees that including the engine crankshaft language in the defini tion of “date of manuf acture” would not be appropriate. EPA does not wish to trigger more stringent standard s for engines that are simply undergoing regular maintenance. Notably, solely removing the engine crankshaft is not an

indication that a substant ial amount of work has been conducted on the engine to the extent that it should have to meet to more stringent emission standards. Consequent ly, EPA is not including

the crankshaft criteria in th e definition of “date of manuf acture” in the final rule. Regarding comments opposing the inclusion of the serial number in the definition of “date of manufacture,” EPA agrees that it would be appropriate to exclude that specific criterion in the final rule. EPA does not wish to requi re more stringent sta ndards for reconstructed engines solely due to the possibility that in some cases, the serial number might not be available, for instance, it may have been knocked off during transportation, use or maintenance, or if the68 engine was acquired and it did not have a tag. EPA is not interested in penalizing affected sources, where information simply is not av ailable or missing based on a technicality, by subjecting them to more stringent standards. Importantly, the lack of the engine serial number is not an indicator that the engi ne has undergone significant modi fication to the point where it should be subject to more stringent standards. Therefore, in th e final rule, EPA has not included

the serial number criteria in the definition of “date of manufacture.” EPA believes that finalizing a cost threshold of 75 percent in the definition of “date of manufacture” is appropriate. Based on the comme nts received, it appears that the majority of the issues surrounding the date of manufacture concept were related to the crankshaft being included in the definition. Since EPA is not including the engine crankshaft as a determining factor for assigning an engine a new date of manufacture, EPA believes that most of the issues brought up by commenters would be resolved. EPA also agrees that the cost threshold analysis should be consistent with what is used for reconstruction, a nd therefore specifies in the final rule that the cost of the new and refurbished components should be compared to the fixed capital cost of a comparable entirely new facility. Commenter 50 indicated to EPA in a meeting on October 26, 2010, that having a consistent cost threshold anal ysis would alleviate its concerns with the 75 percent threshold. 9 Commenter 39 expressed concern with the re quirement that a reconstructed engine consisting of a previously used engine with all new components be given a new date of manufacture. EPA disagrees that a bare engine block with all new components should not be required to meet the emission standards applicab le for a new engine. That type of engine rebuilding would significantly extend the life of the engine, and EPA believes it is appropriate

9 Memorandum from Tanya Parise, EC/R to Melanie King, EPA. Summary of the October 26, 2010 Meeting with the Gas Compressor Association Regarding the Proposed Amendments to the SI NSPS for Stationary Engines. November 10, 2010. EPA-HQ-OAR-2010-0295.69 that the engine meet the most stringent emission standards, and that the equipment necessary to meet those standards can be incorporated into th e extensive rebuilding of the engine. EPA also notes that 40 CFR 60.4210(i) includes replacement engine provisions for stationary CI engines replacing existing equipment that is less than 15 years old. The commenters who pointed out that there was a typo in the preamble concerning when reconstructed engines would be subject to more stringent standards are correct. EPA notes that there was a typo on page 32619 of the preamble to the proposed rule in the middle column. The language in section II.F. that r ead “The fixed capital cost of the new and refurbished components exceeds 50 percent of the fixed capital cost of a comparable new engine” should have read “The fixed capital cost of the new and refurbished components exceeds 75 percen t of the fixed capital cost of a comparable new engine” consistent with the proposed definition of “date of manufacture” in proposed 60.4219 and 60.4248. In response to the commenter who believes th at previous reconstruction determinations conducted using definitions in 40 CFR 60.15 should not be required to be revisited or reevaluated, EPA notes that any provisions finali zed under this rulemaking are not retroactive.

EPA has no control over what Stat e agencies or other regulatory authority may require, but in any event, EPA is not including a separate defini tion for reconstruc tion in the final rule, but is instead pointing to the Gene ral Provisions definition.

9.2.2 Comment : One commenter (50) said that the crit eria for reconstructi on are different in 40 CFR part 63, subpart ZZZZ, and in the proposal unde r 40 CFR part 60, subpart JJJJ. This creates confusion because an engine c ould be defined as reconstructe d under the NSPS and has to meet the new engine standard of 1.0 g/HP-hr of NO x or 3.0 g/HP-hr of NO x , depending on the70 threshold for fixed capital cost. The same e ngine under 40 CFR part 63, subpart ZZZZ, may not be considered reconstructed, and would still be subject to existing requirements under that rule, the commenter (50) said. Accordingly, the comment er (50) stated, this leads to conflicting and duplicative requirements between a new or recons tructed NSPS engine and an existing NESHAP engines. This also directly c onflicts with EPA’s attempts to streamline and simplify compliance, which it stated in the response to comments for the final SI NSPS/NESHAP consolidated rulemaking.

Response : EPA is not finalizing the proposed definition of “reconstr uct,” but is instead pointing

to 40 CFR 60.15 for the definition of “reconstruction.” This is consistent with the definition of “reconstruction” used for 40 CFR part 63, subpa rt ZZZZ, which points to the definition in 40 CFR 63.15. Therefore, the commenter’s issue is resolved.

9.3 Installed

9.3.1 Comment : Two commenters (37 and 55) thought th at the definition of “installed” in sections 60.4248 and 60.4219 of the proposed NSPS should be deleted or modified. EPA proposed to add the following definition: “Installed means the engine is placed and s ecured at the location where it is intended to be operated; piping and wiring for e xhaust, fuel, controls, etc., is installed and all connections are made; and the engine is cap able of being started.” The commenter (55) indicated that installa tion has typically meant the start of site construction, as opposed to when the engine is ready to operate. The commenter (55) expressed71 that it did not anticipate this ch ange and was of the opinion that if the new definition is included in the final rule it should only be applied from the effective date of the rule and not retroactively. Commenter 37 indicated that part of the definition is appropri ate, i.e., in terms of having the engine “placed and secured at a location wh ere it is intended to operate” for defining “installed.” However, the commenter (37) does no t agree with the rest of the definition as that states “...the piping and wiring for exhaust, fuel, controls, etc., is insta lled and all connections are made; and the engine is capable of being started.” The commenter (37) recommended that the final definition read as follows: “Installed means the engine is placed and secu red at the location where it is intended to be operated.” Because stationary engines are of ten part of a larger facilit y, the engines may be placed at the location in advance of completing the rest of th e facility and this could be significantly prior to utilities being completed (including local permits and building in spections). In the commenter’s (37) opinion, creating the foundatio n and placing the engi ne at the location indicates major commitment by the owner and the co mmenter (37) does not believe that it is necessary to finalize the remaining connections in order to demonstrate the owner’s intent, and such connections are typically more related to the larger construction pr oject than the engine

itself.

Response : EPA disagrees that the proposed definition of “installed” should not be included in the final rule. The proposed defini tion of “installed” is intended to describe the point when the engine is capable of being operate d at the site. This is consiste nt with EPA’s previous position,72 notably in the response to comment s on the original CI NSPS proposal. 10 Specifically, EPA stated in response to comment 1.3 that the term “insta ll” refers to “the date the engine is installed at the operator site.” This clearly indicates th at EPA did not mean for th e word “install” to be equivalent to “commence construction,” and EP A explicitly stated that EPA did not want “install” to be interpreted to mean “commence construction.” EPA agrees with commenter 37’s recomm endations regarding the definition of “installed.” EPA agrees that installation should be defined as the engine has been placed and secured where it is intended to be operated, and that the engine does not have to be capable of being started before it can be considered insta lled, since the final piping and wiring may not be completed until well after th e engine is secured in its permanent location.

9.4 Certified Emissions Life

9.4.1 Comment : One commenter (26) indicated that it is supportive of EPA proposing to use “certified emissions life” in place of “useful life.” Commenter 26 said that it is common that “useful life” and “service life” are thought to be the same thing, but in corporating the term

“certified emissions life” will remo ve confusion surrounding this issue. The commenter (26) asked that EPA also incorporate the term into other rules, where appropriate. Commenter 26

said that the transition should be timed to change of model year to avoid scrappage of stocks of emissions labels using the older term. The comm enter (26) said that because drawings for 2011 model year emissions labels are already made and being obtained, the commenter (26) recommended that the terminology does not take effect until 2012 model year or later.

10 Memorandum from Jaime Pagán, EPA to EPA Docket EPA-HQ-OAR-2005-0029. Response to Public Comments on Proposed Standards of Performance for Stationary Compression Ignition Internal Combustion Engines.73 Response : EPA’s revision to change the term “useful life” to “cer tified emissions life” does not create any substantive change to the require ments under the rule and EPA is not making any changes to the labeling requirements themselves . Also, incorporating the term “certified emissions life” into other regulations is beyond the scope of this rule.

9.5 Emergency Engines

9.5.1 Comment : Multiple commenters (24, 30, 32, 34, 41, 42, 43, 44, 47, and 55) had comments regarding the proposed definition of an emergency e ngine in the CI and SI NSPS, particularly as it relates to demand response operation. The proposed language reads as follows: “You may operate your emergency stationa ry ICE up to 50 hours per year in nonemergency situations, but thos e 50 hours are counted towards the 100 hours per year provided for maintenance and testing. Th e 50 hours per year for non-emergency situations cannot be used for peak shaving or to generate income for a f acility to supply power to an electric grid or otherwise supply power as part of a financia l arrangement with another entity; except that owners and operators may operate the emergency engine for a maximum of 15 hours per year as part of a demand response program if the RTO or equivalent ba lancing authority and transmission operator has determ ined there are emergency cond itions that could lead to a potential electrical blackout, su ch as unusually low frequency, e quipment overload, capacity or energy deficiency, or unacceptable voltage level. The engine may not be operated for more than 30 minutes prior to the time when the emergency condition is expect ed to occur, and the engine operation must be terminated immediately after the facility is notified that the emergency condition is no longer imminent. The 15 hours per year of demand re sponse operation are counted as part of the 50 hours of operation per year provided for nonemergency situations. The74 supply of emergency power to another entity or en tities pursuant to financ ial arrangement is not limited by this paragraph (d)(4), as long as the power provided by the fina ncial arrangement is limited to emergency power.” One commenter (43) supports clarifications made to the definition. Two commenters (43 and 55) disagree with the provi sions in 60.4243(d)(4), which li mit operating hours for various types of operation. According to commenters 43 and 55, the proposed time limit for grid support is unnecessarily restrictive, and may, in the co mmenters’ (43 and 55) opinion impact the viability of demand response programs that are important for providing energy reliability. Another commenter (24) also indicated that the 15 hours proposed to be allowed for demand response operation is too restrictive. Although emergency demand response programs are rarely called because of Independent System Operators (ISO) tariff requirements, an engine needs to be allowed to participate in demand response program s for more than 15 hours per year, commenter

24 said. One commenter (30) is in agreement that emergency engines should be allowed to operate in emergency demand response programs. However, the commenter (30) is opposed to EPA’s proposal of a 15 hour restriction on such operation because it may prevent emergency engines from being able to participate in emergency demand response programs because in order to qualify, the engines must meet the ISO ta riff requirements, which specify the minimum number of hours the engine will be able to ope rate. The commenter (30) referred to the petition for reconsideration submitted to EPA on May 27, 2010 11 , on the final NESHAP, which describes in detail the commenter’s just ifications. The petition for reconsideration and supporting documentation were also submitted under this proposed rule. In summary, the commenter (30)

11 Letter from David M. Friedland, Beverage and Diamond, P.C., to Ms. Lisa Jackson, Administrator. Petition for Reconsideration of National Emission Standards for Hazardous Air Pollutants for Reciprocating Internal Combustion Engines, Final Rule. May 27, 2010.75 rationalized not limiting emergency demand res ponse operation to 15 hours per year for the following reasons:

 Emergency demand response programs are benefi cial to the environment, according to commenter 30;

 During dispatch of demand response for capacity and energy emergencies, ISO must

follow North American Electric Re liability Council standards;

 As stated above, allowing only 15 hours per year for emergency demand response operation has the potential of emergency e ngines not qualifying to participate in emergency demand response programs;

 It is rare that emergency demand response programs are called, according to commenter (30) and as a result the chance these engine s will be operated to th e maximum number of hours is small;

 The rationale EPA has provided for suppor ting the 15 hours appears to reflect a misinterpretation of comments previously submitted in support of demand response;

 A number of States allow emergency de mand response operation and none of them restrict operation under such progr ams to 15 hours per year; and

 EPA set a precedent under the greenhouse ga s reporting final rule for the use of emergency engines in emergency demand response programs. Commenter 30 recommended that EPA specify that emergency engines can operate for a maximum of 60 hours per year or the minimum hour s required by the ISO tariff, whichever is

less. In this definition, two commenters (43 and 55) recommended that EPA should strike the 15 hours per year limitations for demand response programs because operation is only authorized76 if warranted by a legitimate emergency regardin g power availability. Commenter 43 indicated that EPA should also make this change to the NESHAP when EPA has an opportunity to do so.

If EPA does not eliminate the 15 hours restrictio ns, the commenter (55) argued that EPA should justify such a decision and provi de the environmental and cost benefit of this restriction. According to one commenter (32), in general, industry’s interpretati on of the definition of an emergency engine is that the power source mu st be abruptly interr upted in order to be classified as an emergency. In the commenter’s (32) opinion, the definitio n is a reactionary one that does not work well in emergency planning a nd certain emergencies can be anticipated by the use of weather event tracking and utility monitoring. In such cases , provisions can be made in advance to minimize the impact of the emergenc y, the commenter (32) said, who further cited a

recent tornado storm that was tracked in Wisc onsin 30 to 60 minutes prior to impact, and information like that is used to prepare em ergency generators to prevent actual power interruption. The commenter ( 32) added that frequently util ity networks who observe rapid decline in reserve capacities will take preventativ e action in order to prevent grid collapse by setting up agreements with large electricity consumers to “go off the grid” for a short duration. According to the commenter (32), the maximum hour s defined in the agreements are between 80 and 100 hours, but all those hours are rarely used , in the commenter’s (32) experience. The commenter (32) emphasized the importance of including such flexibility for national grid reliability and safety and does not believe it woul d deter from environmental goals. Specifically, the commenter (32) recommended that EPA reta in the 50 hours per year for non-emergency purposes. Further, the commenter (32) reco mmended that in 60.4211(f)(4), EPA delete the limitation of not operating the engine more than 30 minutes prior to the time when an emergency is expected to occur and the requirements to shut down the engine immediately following the77 event. Similarly, another commenter (34) disa grees with these limitati ons in both 60.4211(f)(4) and 60.4243(d)(4) and indicated that it would expect disputes with respect to the term “immediately.” The commenter (34) asked wh y 30 minutes would be acceptable, but why 31 minutes would not be. Also, the commenter (34) wanted to know what criteria are supposed to be used to determine when the emergency conditi on is expected to occur and to determine when the emergency condition is no longer imminent. The commenter (34) indicated that it believes that most entities are not interested in operating emergency generators any longer than necessary. The commenter (34) recommended th at EPA remove the time restrictions or keep them only as guidelines and require records only to indicate the time and purpose of generator operation. Commenter 32 argued that emergency situations often lead to opera tional decisions that are difficult and that vary on a case-by-case basis, and the comment er (32) believes this should be left within the management of the 50 hour lim it. The commenter (32) is of the opinion that the allowance provided for demand response operati on should be increased to a minimum of 100 hours. According to the commenter (32), this is a typical length of the agreement between the utility and the facility. Finall y, the commenter (32) added that one could argue that EPA could allow an indefinite period for demand response oper ation that would be subject to audits of this type of operation. The commenter (32) said th at the key factors of needing demand response operation is overall grid reliability and frequency of disruptive weather events and are matters of public record. One commenter (47) asked that EPA allo w 60 hours per year for demand response operation arguing that 15 hours is too restric tive in ensuring nationa l grid reliability. Commenters 24 and 30 also requested that EP A specify that 60 hours are allowed. The commenter (47) believes that emergency demand response operation is in frequent and only to78 prevent brownouts and blackouts. The power genera ted during these events is not supplied to the grid, but is used at the facil ity, the commenter (47) stated. Allowing demand response operation prevents rolling brownouts and blackouts from ha ppening and without it reduction in power and power outages would increase, according to comme nter 47. The commenter (47) cited language in the proposed amendments claiming that EPA acknowledged the need for emergency demand response programs in 60.4211(f)(4) and 60.4243(d)(4). The commenter (47) recommended that the demand response limit be removed or alternat ively that EPA revise 60.4243(d)(4) to read: “...owners and operators may opera te the emergency engine for a maximum of 60 hours per year or the amount of time required by the Independent Sy stem Operator tariff, whichever is less, as part of a demand response program...” Three commenters (24, 30, and 47) also recommended that EPA remove the provision that counts the hours used for emergency demand response purposes towards the 50 hours per year in non-emergency situations. One commenter (41) stated that the proposed amendments are in direct conflict with

section 69.3.5 of the Midwest ISO Federal En ergy Regulatory Commi ssion (FERC) approved Open Access Transmission and Energy and Opera ting Reserves Markets Tariff. The Midwest ISO’s Tariff, which has been approved by FERC, allows entities to obtain demand resources for generating capacity during emergency condition s, which frequently includes engines, the commenter (41) said. The Tariff states at 69.3.5(iv) and (v) that a demand resource that qualifies as a capacity resource must be able to operate (during emergency conditions where the reliability of the electric grid needs to be maintained) at least five times for at least 4 continuous hours per event during the summer season. Therefore, any e ngine that could qualify to be considered for such operation has to be able to be operated for a minimum of 20 hours per year, the commenter (41) said, who added that similar requirements are including in other Regional Transmission79 Organizations (RTO). The commenter (41) requested that EPA allow additional time for demand response operation consistent with qualif ication requirements developed by RTO and approved by FERC. As such, the commenter (41) asked that EPA allow such operation to be at least 20 hours per year and that such operation be considered an emergency situation as opposed to a non-emergency situations and accounted for accordingly. The commenter (41) acknowledged the potentia l environmental impact, but asked that EPA recognize the significant of balancing environmental concer ns with the importance of main taining grid reliability during emergency conditions. One commenter (42) asked that EPA recons ider the language in the emergency engine

definition that restricts em ergency demand response operation to 15 hours per year. One commenter (44) asked that EPA delete the de finition of emergency demand response in the proposed definition of emergency engine. Also, the commenter (44) asked EPA to clarify between emergency response units and price response units in th e definition because there are differences between how emergency generator ope rations are treated by ISO. The commenter (44) suggested that EPA review the following definition of “real-time emergency generation resource” from the ISO New England, Inc. Tran smission, Markets and Services Tariff, FERC Electric Tariff No. 3, i ssued December 22, 2004: “Real-Time Emergency Generation Resource is Distributed Generation whose Federal, State and/or local air quality permits limit operati on in response to requests from the ISO to the times when the ISO implements voltage reductions of five percent of normal operating voltage that require more than 10 minutes to implemen t. A Real-Time Emergency Generation Resource must be capable of: (i) curtaili ng its end-use electric consump tion from the New England grid80 within 30 minutes of receiving a Dispatch Instru ction; and (ii) continui ng that curtailment until receiving a Dispatch Instructi on to restore consumption.” The commenter (44) recognizes the need for emergency generation and on-peak demand response to provide reliable el ectricity delivery, and acknowledges, as demonstrated in 2003, the substantial health and economic impact associated with wide-scale grid failure. Regardless, operating emergency engines to create electricity for on-pe ak demand during high electric demand days (HDDE) creates significant public hea lth impacts, such as high emission rates of ozone precursors and air toxics, co mmenter 44 said. Such high emission rates significantly make problems worse on air quality that is alrea dy impaired during HDDE. Consequently, the commenters (42 and 44) believe that EPA should discourage the use of emergency generators unless it is for a true power emergency. For real emergencies (incl uding blackouts and brownouts, including periods of 5 percent voltage reduction), the commenter (55) does not believe that EPA should have to limit the number if the definition of “emergency” is spec ific and restrictive e nough to prevent operating for price-response purposes. Co mmenter 42 also cited the above tariff and argued that current market rules and definitions established by IS O-New England (ISO-NE) are sufficient enough to adequately restrict the use of emergency e ngines for financial reasons. Therefore, the commenter (44) recommended that EPA finalize a definition of emer gency that specifically lays out the conditions, including periods of 5 per cent voltage reduction, illustrated by the ISO-NE

cited above. Commenter 42 similarl y requested that EPA adopt rules similar to those in effect in New England through the ISO-NE Tariff or allow regions to define their own programs that restrict the use of emergency engines in a way that is consistent with EPA’ s goals without strictly limiting the number of hours of pa rticipation. Further, the comme nter (44) requested that EPA81 coordinate with FERC to determine the estim ated energy and environmental benefit from implementing this definition of emergency on a nati onal level to be used by all ISO. Also, the commenter (44) recommended that EPA set standard s that will provide incentives to dispatch non-generating demand response resources prior to the dispatch of polluting demand response resources. Additionally, the commenter (44) sa id that EPA should make sure that control technology matches the intended use of emergenc y engines that are used to meet on-peak demand for quick start capacity and require that emission controls ar e operating at full efficiency as soon as possible and no later than 10 minutes after engine start-up or the time recommended by the engine manufacturer if add-on controls such as SCR is used. One commenter (42) encouraged EPA to re view material developed by Synapse Energy Economics, Inc., referenced in the Petition fo r Reconsideration filed by CPower, EnergyConnect,

EnerNOC and Innoventive Power. The material c oncluded in fact that availability of these resources could improve air quality when used to provide system reserves, under certain dispatch models, the commenter (42) said. According to the commenter (42), in these cases, emergency engines would be providing non-spinning quick st art reserves in place of old load-following boilers providing spinning reserves through th eir operation at minimum load. The commenter (42) argued that emergency engine resources ar e vital parts of the resource mix that displace other types of power and play an important ro le in ensure electric grid reliability. Another commenter (24) argued similar points that it is critical to allow stationary emergency engines to participate in demand respons e programs in order to stabilize the electric grid. Consistent with other commenters, EPA s hould not institute regulati ons that conflict with existing emergency demand response programs that are also endorsed by several States with no

restrictions on the numbers of hour s, the commenter (24) said. Th e commenter (24) cited to the82 ISO-NE, and to language in various New Engl and State regulations addressing emergency engines. The commenter (24) i ndicated that under the ISO-NE, operators are fully aware that operation is only permitted during emergency cond itions and such conditions are clearly defined when the ISO-NE declares Operating Procedure (OP) 4, Action 12. 12 According to the commenter (24), the emergency demand response pr ogram is totally independent of the ISO-NE price response program, and emergency engine s are only contracted to operate under OP 4,

Action 12 conditions and not in th e price response program. Pe r the commenter (24), in New England, OP 4, Action 12 has rarely been declar ed. Further, the commenter (24) said, the emergency demand response program also includes cutting power to other devices at a facility, such as minimizing heating, ventilation and ai r conditioning (HVAC) and lighting loads shutting off factory machines. The commenter (24) added that over the last few years, the States of Connecticut, Massachusetts, Rhode Island, and Ne w Hampshire have revised their emergency engine definitions to allow th ese engines to participate in the ISO-NE emergency demand response program. According to the commenter (24), the State of Vermont has implemented a policy allowing emergency engines to partic ipate in ISO-NE emergency demand response programs and Maine permits engines on a case-by-case basis if engines exceed permit thresholds. The commenter (24) cited the definitions of emergency engines from several New England State regulations, highlighting language related to emergency demand response program provisions, adding that the States do not limit th e hours of operation for en gines participating in the ISO-NE emergency demand response program. The commenter (24) also discussed the RTO

of much of the Mid-Atlantic and Midwest region of the countr y, namely PJM Interconnection who has an equivalent program called the Emergency Load Response Program (ELRP).

12 Under Forward Capacity Market (“FCM”) this Action is now known as Action 6 Real Time Emergency Generation (“RTEG”).83 According to the commenter (24), it is more advantageous to preven t a blackout by utilizing a group of emergency generators for a short time rather than losing the grid, in which case the commenter (24) said would mean that all emer gency generators in the State would have to operate for several hours of perhaps days. Engines used under the ELRP will not be synched with the grid, commenter 24 said, but will only be turned on when the RTO declares an emergency on the ELRP, consequently reducing the demand on the grid. In addition, owners are asked to reduce their power by limiting their HVAC and light usage, for instance, the commenter (24) said. The ELRP is engaged under th e provisions in the PJM Manual 13 Emergency Operations for a PJM Declared Emergency, a condition where the RTO alerts electric

distributors that there is an emer gency or that an emergency is expected and it is necessary to follow procedures under PJM Manual 13 Emergenc y Conditions. Again, the commenter (24)

said that ELRP has seldom been declared and stre ssed that it is strictly in place for emergency situations, plus it is not associated with ot her PJM programs related to financial gain, e.g., economic response or peak shaving. Betw een the years 2003 and 2009, the ELRP has been called only five times where the event lasted between 3 and 5 hours. The commenter (24) referred to how emergency engines area trea ted in various States, such as Maryland, Pennsylvania, Virginia (allows a maximum of 60 hours for emergency engine operation under ELRP), Ohio, Illinois, West Vi rginia, Allegheny County (the division handles ELRP requested on a case-by-case basis and has so far approved permits with 60 hours as the limit), and Indiana, who include provisions for emergency demand re sponse operation in their regulations, and once again noted that these States typically do not limit the hours allowed for operation during the ELRP. The Electric Reliability Council of Texas (ERCOT) ha s the Emergency Interruptible Load Service (EILS), a program developed as a la st resort in order to prevent electric grid84 failure, the commenter (24) said. The program is part of the Electrica l Emergency Curtailment Plan (EECP) and is expected to be called during a Stage 3 emergency. At that point, everything else has been tried according to the commenter ( 24) and to prevent a rolling blackout, emergency generators are used to power facilities, reduc ing demand on the grid. The program is designed for a maximum number of six disp atches per year for a total of 24 hours per year at most, the commenter (24) said. In Texa s, most emergency engines operate under a permit by rule and under this, operation in the ERCO T EILS Program is not restrict ed and there are no hour limits for such participation either. The commenter (24) argued that EPA preceden t exists for allowing emergency engines to operate in demand response programs without rest rictions, e.g., in EPA’s Mandatory Reporting of Greenhouse Gases rule, EPA exempted emergenc y engines from reporting greenhouse gases. EPA defined emergency generators as follows in that rule (74 FR 56387): “[a]n emergency generator operates only dur ing emergency situations, for training of personnel under simulated emergency conditions, as part of emergency DR procedures, or for standard performance testing procedures as requi red by law or by the generator manufacturer.” The commenter (24) said that EPA did not include any restrictions on the emergency demand response hours in that rule. The comment er (24) closed by emph asizing the importance of EPA not finalizing requirements that are inc onsistent with how many regions of the country handle emergency demand response.

Response : EPA proposed to amend the definition for “emergency stationary internal combustion engine” and the allowances for maintenance/ testing and non-emergency operation for such engines to be consistent with the provisions promulgated in the NESHAP for existing stationary85 reciprocating internal combustion engines (RICE) at 40 CFR part 63, subpart ZZZZ. EPA is only finalizing a portion of the pr oposed revisions to the emergenc y engine definition. EPA is finalizing the provision allowing 50 hours of non-emergency service for stationary CI engines subject to the NSPS, in order to make the em ergency engine provisions for new CI engines consistent with those for new SI engines and existi ng CI and SI engines. At this time, EPA is not finalizing the proposed provi sion allowing 15 hours for demand response operation for emergency stationary engines. EPA included a similar provision for emergency engines in the March 3, 2010, amendments to the stationary RICE NESHAP (75 FR 9648), and subsequently proposed to amend the stationary engine NSPS to be consistent with the stationary RICE NESHAP. EPA received two petitions for recons ideration of the 15-hour allowance for demand response in the stationary RICE NESHAP, and is currently reconsiderin g its decision to allow emergency engines to operate for 15 hours per ye ar as part of an emergency demand response program. EPA is deferring taking final action on in cluding this provision in the stationary ICE NSPS pending the resolution of th e reconsideration process on th e stationary RICE NESHAP.

EPA will address this issue as it affects the CI and SI NSPS emergency engine provisions as part of that reconsideration process.

9.5.2 Comment : Two commenters (43 and 55) noted some concerns with the proposed definition of emergency engine. In order to prevent confusion, commenters 43 and 55 recommended that EPA remove the sentence in the pr oposed definition that reads “Sta tionary SI ICE used for peak shaving are not considered emer gency stationary ICE,” which the commenter (55) believes

conflicts with the last se ntence of the definition.86 Response : As discussed in the response to comme nt 9.5.1, EPA is not finalizing the proposed definition for emergency stationary internal com bustion engine at this time. Regardless, EPA disagrees with the commenters and does not belie ve the commenters’ recommendation to remove the language as suggested is appropriate. Peak shaving is not the sa me as grid support and

therefore EPA does not believe t hose two sentences conflict.

9.5.3 Comment : One commenter (37) agrees that it is appropriate to allow emergency engines to participate in demand response programs for a limited number of hours. The commenter (37) concurs that only a very limite d amount of time should be allowed to demand response purposes and opposes an amount higher than what EPA propos ed. The commenter (37) is of the opinion that if a generator is to be used for demand re sponse, peak shaving or other non-emergency use, those engines should meet the standards applicable to non-emergency engines.

Response : No response is needed.

9.5.4 Comment : Two commenters (21 and 35) indicated that healthcare facilities have been significantly impacted by restri ctions in the original CI NSPS. An increase in power interruptions due to utilities not having the in frastructure needed to manage increased loads during inclement weather and power anomalies ha s worsened the problem, according to the commenter (35). This presents a danger to hea lthcare facilities that have consequently entered into demand response agreements with utilities in order to deal with unreliable power, the commenter (35) said. Issues re lated to power will increase an d according to the commenter (35) will likely exceed the 15 hours per year. Therefore, commenter 37 urged EPA to revise 40 CFR87 60.4211(f)(4) to remove the 15 hours limitation and re place it with allowing any period of period under a demand response program. The commenter (3 5) also recommended the stipulation that the engine cannot be operated for more than 30 minutes prior to the time when the emergency condition is expected to occur be removed, specifically suggesting the following revisions: “The engine may not be operated for more than 30 minutes prior to the time when a period of time that the emergency condition is expected to exist occur , and then the engine operation must be terminated immediately after the facility is notified that the emergency condition is no longer imminent. The 15 hours per year of dema nd response operation are not counted as part of the 50 hours of operation pe r year provided for non-emergency situations.” Two commenters (21 and 35) do not believe that incorporat ing these suggested changes

into the final rule will detract from the intent of the proposed changes and indicated that these changes will provide an increased le vel of protection for healthcare fa cilities’ patients and staff. The commenters (21 and 35) provided w ith its comment letter a publication 13 on diesel generators and noted how the re port indicates how diesel genera tors may be a clean and cost effective solution to the power crisis.

Response : As discussed in the response to comme nt 9.5.1, EPA is not addressing the issue of emergency demand response, including the restriction on operation more than 30 minutes prior to an emergency, at this time. EPA is deferri ng taking final action on in cluding this provision in the stationary ICE NSPS pending the resolution of the reconsideration pr ocess on the stationary

RICE NESHAP.

13 Backup Generators (BUGS):The Next Smart Grid Peak Resource.U.S. Department of Energy. 4/15/2010. http://www.netl.doe.gov/smartgrid/r eferenceshelf/whitepapers/BUGS_The%20Next%20Smart%20Grid%20Peak%2 0Resource%20(April%202010).pdf

.88 9.5.5 Comment : One commenter (33) indicated that it thinks that additiona l clarification and language is needed to adequate ly describe demand response operation and peak shaving. The commenter (33) said that how industry descri bes demand response operation does not appear to match how EPA has described it in the proposed amendments and the commenter (33) believes this can cause confusion as far as which engi nes are for emergencies and which are for peak shaving. Because the proposed rule allows emer gency engines to participate in demand response programs, according to the commenter (33), sources may think their engines would be considered emergency engines. The commenter (33) pointed out however, that the demand response programs developed by the utility i ndustry utilize these engines for non-emergency purposes to reduce the cost to provide power during high demand. 14 According to commenter 33, the only motivation for end-use customers to pa rticipate in demand response programs is for financial gain and participati on does not provide addi tional stability for th e end-use customer because it already has an emergency engine to provide power during a blackout. The commenter (33) said that there is additional confusion in the proposed amendments because the commenter (33) does not believe that EPA has adequately described the emergency conditions that qualify an engine to participate in demand response ope ration. The commenter (33) referred to the North American Electric Reliability Corporat ion’s (NERC) Capacity and Energy Emergencies (Standard EOP-002-2) regarding energy emerge ncy alerts, suggesting that this document 15 might be helpful to EPA in identifying emergency cond itions that would allow the use of engines for emergency energy response operation, which states that an “Energy Emergency Alert is an emergency procedure, not a daily operating pr actice...” Subsequently, the commenter (33)

14 http://pjm.com/markets-and-operations/demand-response.aspx , http://pjm.com/markets-and-operations/demandresponse/~/media/markets-ops/dsr/20100707-dsr-hight-load-day-report.ashx , and http://pjm.com/markets-andoperations/demand-response/~/media/markets-ops/dsr/demand-response-fact-sheet.ashx

. 15 http://www.nerc.com/ files/EOP-002-2.pdf

.89 recommended that Alert 2 status, as detailed in this document, be required prior to emergency engines being allowed to be utilized for dema nd response operation. In the commenter’s (33) opinion, a copy of the Alert 2 report would be sufficient to demons trate that the engine qualified demand response operation and the report is typica lly available online th rough NERC’s website. In terms of peak shaving, commenter 33 in dicated that it unders tands this might be necessary during peak demand, but the commenter (33) said that such operation is not an emergency. The use of these engines during a no n-emergency situation yields financial benefit without having to control emissions, the commenter ( 33) said. Even if each engine is allowed to operate for only 15 hours per year, PJM Interc onnection, an RTO with an emergency demand reserve of 2,144 megawatt (MW), can result in a la rge influx of emissions in a very short time period, the commenter (33) said. For example, using AP-42 emission factors for stationary CI engines below 600 HP, the commenter (33) esti mated that the 15 hours of operation within PJM’s fleet would equate to about 668 tons per year (tpy) of NO x emissions, 144 tpy of carbon monoxide (CO) emissions, 47 tpy of PM 10 emissions and 53 tpy of total organic compounds. The commenter (33) believes that these engines should be subject to the same requirements that apply to non-emergency engines. At the very least, the commenter ( 33) recommended that EPA clarify the difference between peak shaving and demand response.

Response : As discussed in the response to comme nt 9.5.1, EPA is not addressing the issue of demand at this time. EPA is deferring taki ng final action on including this provision in the stationary ICE NSPS pending the resolution of the reconsiderat ion process on the stationary RICE NESHAP. As noted in the response to comment 9.5.2., EPA agrees that there is a90 significant difference between peak shaving and emergency demand response, and allowance of the latter for any amount of time does not imply allowance of the former.

9.5.6 Comment : Two commenters (24 and 34) said that EPA should change the reference from 60.4211(e) to 60.4211(f) in the definition of an emergency engine in 60.4219 in the proposed

rule.

Response : EPA agrees that the proposed defini tion should have referenced 60.4211(f) in the proposed rule.

9.5.7 Comment : One commenter (28) noted significant concern with regards to EPA’s proposal to allow emergency engines to participate in emergency demand response operation even for a limited amount of time. The commenter (28) be lieves that allowing emergency demand response operation could have detrimental effects on Delaware ’s ability to attain and maintain compliance with National Ambient Air Quality Standards (NAAQS) and strongly di sagrees that demand response should be included as emergency use. The commenter (28) emphasized the importance of true emergency operation, as for example backup power at a hospital when the main electricity is unavailable or at chicken farms where heating or coo ling is crucial to avoid deaths. On the other hand, the commenter (28) argued that emergency generators are being utilized for

other reasons where electric ut ilities have created demand res ponse programs that are, in the commenter’s (28) opinion, contrary to the anti cipated use of emergency power generation, which negatively impact air quality. These emergenc y units emit HAP and emit high levels of NO x on a mass and rate basis, the commenter (28) said, arguing that the time when these engines operate91 (i.e., during demand response) is during the wors t conditions for developing ground-level ozone. The commenter (28) cited to an example wh ere in Delaware, a demand response program consists of roughly 225 uncontrolled generators less than 300 KW. The owners of these engines are according to commenter 28 in agreement w ith the utility to provide power during peak

demand scenarios and receive lower electric rate s in return. Per commenter 28, these engines have typically operated on very hot sunny summer days and emit a substantial amount of HAP

and above 1.6 tons of NO x in a 3-hour period, the commenter ( 28) said. Finali zing the definition of emergency engine as proposed will lead to th ese engines directly impacting air quality with respect to ground-level ozone, the co mmenter (28) believes. If EPA allows this type of operation during peaking times, it would circumvent and undercut Delaware’s efforts and progress in reducing emissions. The commenter (28) contended that if emerge ncy generators in the entire Northeast are allowed to operate without cont rols in demand response programs, emissions

would be substantial and have detrimental e ffects on ground level ozone. The commenter (28) pointed to a 2003 Northeast States for Coordi nated Air Use Management (NESCAUM) report 16 on stationary diesel engines, which indicate th at there are about 26,890 em ergency diesel engines with the ability to generate 8,760 MW of em ergency capacity in the NESCAUM region. The commenter (28) cited to a recent event wher e PJM activated the ELRP on July 7, 2010, where the event lasted 4 hours for most areas that pa rticipated. Using available information on the actual capacity utilized that da y under ELRP, reasonable assumpti ons regarding the number of emergency generators that particip ated in the event, and the type of emissions controls installed on the generators, the commenter (28) estimated th at the event could have generated close to 218

tons of NO x . For comparison, the commenter (28) said that Delaware’s entire statewide peak

16 Stationary Diesel Engines in the Northeast: An Initial Assessment of the Regional Population, Control Technology Options and Air Quality Policy Issues. Northeast States for Coordinated Air Use Management.92 ozone season daily NO x emissions were 182 tons in 2005. The commenter (28) argued that using other assumptions in this estimation, e.g., by assuming that the generators were older and smaller, it is possible that the amount of NO x emitted that day could ha ve been on the order of 272 tons. However, the commenter (28) said that these are conservative estimates and it is likely that not all the load shed was due to emergency generators. In fact, information the commenter (28) was provided with showed that the NO x emitted was 46 tons on July 7, 2010. Regardless what the figure is the commenter (2 8) said it is a substantial amount. The commenter (28) indicated that it wish ed to model the emergency demand response using the CALGRID air quality model, but due to additional research necessary in order to complete the assessment, it was not feasible in the timeframe required to provide comments on the proposed rule to finish the modeling. Cons equently, the commenter (28) asked that EPA conduct its own analysis to model the effects of July 7, 2010, to understand the impacts of emergency demand operation. The commenter (28) indicated that according to an inquiry conducted on EPA’s AIRNow website, monitors in the Philadelphia non-attainment area on July 7, 2010, indicated that 15 ozone monitors exceed ed the 75 parts per billion (ppb) 8-hour ozone NAAQS (based on preliminary data). Further, th e commenter (28) claims that there would have been NAAQS exceedances on almost all of the days where the ELRP was in effect. The commenter (28) pointed to other events that it believes demonstrate the negative environmental effect of allowing emergency generators to operate. The commenter (28) submitted additional information following its original comment letter to support claims that dies el generators directly cause or contribute to viol ations of EPA’s 1-hour nitrogen dioxide (NO 2 ) NAAQS, which became effective in April 2010. These comments are represented as commenter 45. Th e commenter (45) submitted information on a93 modeling analysis that indicate that diesel emergency and pe ak shaving engines cause and

contribute to 1-hour NO 2 levels as high as 4 times the NAAQS. The commenter (45) reiterated its point that diesel engines th at are aggregated for demand re sponse purposes have substantial negative impacts on ozone levels (specifically in terms of NO 2 ) and should not be allowed to participate, in an uncontrolled fashion, in demand response programs.

Response : As discussed in the response to comment 9.5.1, EPA is not taking any action regarding emergency demand response at this time. EPA is deferring taking final action on including this provision in the stationary ICE NSPS pending the resolution of the reconsideration process on the stationary RICE NESHAP.

9.5.8 Comment : One commenter (52) provi ded additional comments (t he commenter’s original

comments are reflected under comme nter 30-see Table 1 of this document) in rebuttal to comments submitted by commenter 28. The comment er (52) thought that the concerns from commenter 28 are misguided in that commenter 28: 1) confuses emergency demand response with economic demand response; 2) confuses reserve margin with emergency conditions; 3) significantly overestimates emissions from em ergency demand response; 4) misstates the Synapse Study; and 5) inappropr iately uses emissions decrease during a blackout as a reason to prohibit emergency demand response. Regardin g item 1), commenter 52 said that emergency demand response programs are only used for grid emergencies, whereas economic demand response are dispatched by the utilities or ISO in response to high prices or are self-selective by end users in response to prices . These two programs are substa ntially different, commenter 52

said and EPA should treat them as such. The commenter (52) does not believe that commenter94 28 has made a distinction between these two types of programs; emergency demand response is operation as a last resort to avoid blackouts and economic demand response is operation such as peak shaving or other types of non-emergency operation. The commenter (52) reiterated that emergency demand response is tightly controlle d under NERC regulations for the sole purpose of responding to grid emergencies. The examples provided by commenter 28, which the commenter (28) indicates is emergency demand re sponse, is, in fact, economic demand response (see page 2, second paragraph, and page 3, fi rst full paragraph of EPA-HQ-OAR-2010-0295- 0028), and the language in EPA’s NSPS and NES HAP regulations specifically exclude peak shaving and other economic gain while operating emergency generators. In response to item 2), commenter 52 said that contrary to what commen ter 28 said, there is no buffer when the electric need is above the required reserve margin. A ccording to commenter 52, the grid operator only calls emergency demand response when reserves are used up or close to be used up. In response to item 3), commenter 52 said that commenter 28 estimated that NO x emissions were between 218 and 272 tons during the demand response even t on July 7, 2010. However, the commenter (52) said, commenter 28 incorr ectly assumed that all that emergency demand response was a result of emergency generator operation. In f act, 75 percent of the emergency demand response on that day was a result of curtailment (e.g., tu rning down lights, reducin g HVAC needs, etc.) Assuming that 25 percen t originated from emergency generators, NO x emissions are estimated to

be less than 46 tons that da y and possibly even less. Th e Synapse Energy Economics Study 17

, which commenter 52 submitted as part of its pe tition for reconsideration for the NESHAP and attached to the commenter’s (52) comments on this proposed rulemaking, evaluated the impacts of demand response and energy efficiency program s in New England using an electric system

17 Modeling Demand Response and Air Emissions in New England. Prepared by: Geoff Keith, Bruce Biewald, David White and Mike Drunsic. Synapse Energy Economics. Prepared for U.S. Environmental Protection Agency. August 2003. Revised: September 4, 2003. EPA-HQ-OAR-2010-0295-0030.3.95 dispatch model. The conclusion of the study wa s that emergency demand response improves air quality. Commenter 52 disputed commenter 28’s claim that th e report assumed that the nonemergency generators were gas-fired, first by stat ing that the report also indicates that if all demand response operation is from diesel engines, there is still a net air quality benefit. The

benefit increases if some of the fuel is assumed to be gas, the commenter (52) said). Secondly, the commenter (52) said that emission factors fr om eight different types of operation were used (gas-fired combined cycle, oil-fired combined cycle, gas-fired combustion turbine, oil-fired combustion turbine, and coal, gas, oil, and wood- fired steam plants). According to commenter 52, the Synapse Study concluded th at “when the DR resource is used to meet reserve requirements, the result is more efficient unit commitment, reduce operation of oil- and gas-fired steam units and increased operation of combined-cycle units in New England. 18 The commenter (52) also cited the following additi onal conclusion from the study: “New England has a small amount of quick-sta rt capacity relative to the regional peak load compared to most other control areas. Many analysts have noted th at this requires large power plants to operate more than they would ot herwise have to in order to maintain sufficient operating reserves – capacity th at can be provided quickly in response to unplanned losses of capacity. A key goal of this work for EPA was to verify that large units were indeed being operated more than necessary in New England to meet reserve requirements, to gauge the probable emission impacts of this dynamic, and to estimate potential emission reductions that additional DR could provide if it were used to meet operating reserve requirements. 19 ” Commenter 52 stated that according to the re port, demand response is used for reserves

there are substantial decreases of criteria pollutant emissions, even under the assumption that all

18 Id. See page 2. 19 Id. See page 4.96 fuel used is diesel (NO x decreased 23 tons, SO 2 decreased 216 tons, carbon dioxide decreased 31,400 tons, PM 2.5 decreased 12.5 tons, and PM decreased 21.2 tons. 20 Regarding item 5), commenter 52 said that it is not realistic to sacr ifice electricity for

reduced emissions. Commenter 52 said that it is nonsensical to use as an argument that emissions actually go down duri ng a blackout in order to suppor t the preclusion of emergency demand response. Grid failure is a serious conc ern, which affects public health and safety and

can also cause severe en vironmental damage.

Response : As discussed in the response to comment 9.5.1, EPA is not taking any action regarding emergency demand response at this time. EPA is deferring taking final action on including this provision in the stationary ICE NSPS pending the resolution of the reconsideration process on the stationary RICE NESHAP.

9.6 Freshly Manufactured Engines

9.6.1 Comment : Two commenters (37 and 40) believe th at EPA should remove the reference to previously used parts in the definition of a fr eshly manufactured engine . The proposed definition

reads as follows: ”Freshly manufactured engine means an engine that has not been placed into service. An engine becomes freshly manufactured when it is originally produced. Note that this includes an engine that is produced using some previously used parts if it does not retain its original identity.”

20 Id. See page 13.97 One commenter (40) asserted that if the last sentence of the proposed definition is finalized as proposed, it will disproportionately impact stationary engine remanufacturing and

would be inconsistent with sec tion 202(a)(3)(D) of the CAA. One commenter (37) opposes the inclusion of previously used engi nes in the definition, noting that it differs from the marine and nonroa d engine definitions, and impacts the standards for previously used and remanufactured engine s. In the commenter’s (37) opinion, including used parts as part of freshly manufactured produ cts is fundamentally wrong in that those parts have previously be in service. The commente r (37) expressed the impor tance of remanufactured engines and the value of the remanufacturing pr ocess to the industry. The proposed definition would eliminate the option of remanufacturing by applying a new date of manufacture to such engines requiring the remanuf acturing process to meet the same requirements (including certification, where applicable) as the process where new engines are built on an assembly line using completely new parts, the commenter (37) said. The commenters (37 and 40) indicated

that the definition does not take into consideration the technical or cost feasibility of updating existing components to meet the latest standards, as if they were new components. Used components are not new components and the co mmenter (37) conse quently argued that remanufactured engines with used parts should no t be considered new or freshly manufactured engines. According to the commenters (37 and 40), remanufactured engines are more similar to rebuilt or reconstructed engines (as opposed to new or replacement engines) and should be treated as such. Replacement engines are bui lt entirely from new components according to certified methodologies, commenter 40 said, and it is therefore mo re appropriate to group newly manufactured engines and replacement engines together. Conversely, remanufactured, rebuilt and reconstructed engines are built from a combin ation of used and new components and should98 therefore be grouped together, th e commenter (40) asserted. A ccording to commenter 40, this would be consistent with EPA’s prior findings concerning remanufactured and rebuilt engines and with statutory obligations under section 202(a)(3)(D) of the CAA. Commenter 40 said that EPA is authorized to regulate “rebuilding pr actices” for heavy-duty engines, but EPA can only implement requirements for rebuilding practices if the Administrator does the following: 1) studies such practices, 2) finds, based on that study, that rebuilding practices “cause, or contribute to, air pollution whic h may reasonably be anticipated to endanger public health or welfare taking costs into account,” and 3) provides sufficient lead time for technology to develop to meet the new regulations. The commenter (40) cited an EPA study 21 conducted to investigate the rebuilding and remanufactur ing industry under section 20 2 of the CAA and a broader industry characterization 22 conducted under EPA’s direction, wh ich the commenter (40) clearly indicated that remanufacturing is a form of “out-of-frame” overhau l or rebuild. Accordingly, the commenter (40) said, EPA’s vi ew is consistent with the commenter’s (40), i.e., that remanufactured should be grouped with re built and reconstruc ted engines. The commenter (40) cited the following EPA conclusion from the section 202(a)(3)(D) study, which commenter 40 believes is clear and unequivocal: “Based on the study findings, regulations to control rebuilding practices applicable to current technology heavy-duty engines are not warranted to ensure th at rebuilt engines meet the emission certification st andards that applied to the engines when new . [Emphasis added by commenter 40]. The study demonstrated that current technology rebuilt engines generally emit below the standards applicable when such engi nes were new. While rebuilding extends the

21 See for example pages 6-7 of Industry Characterization: Nonroad Heavy Duty Diesel Engine Rebuilders. ICF Incorporated, 1997. EPA-HQ-OAR-2005-0119-0004. 22 See for example Notice of Agency Co mpletion of Study Regarding Heavy-Duty Engine Rebuilding Practices and Availability of Documents, 60 Fed. Reg. 42881, 42882 (Aug. 17, 1995).99 actual life of engines, it does not appear that the emissions char acteristics of current engines deteriorate as a result of rebuild. Furthermore, most emissions critical components are currently replaced or adjusted duri ng a typical engine rebuild.” Again, the commenter (40) stressed that incl uding the sentence at issue would necessitate certification of remanufactured engines to curr ent standards and fundamentally change EPA’s previous regulatory treatment of these engines. Further, fina lizing the definition as proposed

would reduce or remove the numerous benefits associated with remanufacturing in terms of including decreased use of natural resources, improved energy efficiency, decrease in carbon emissions, and minimizing landfill space, according to the commenter (40). This would also contravene EPA’s prior findings regarding remanufactured engines and be inconsistent with section 202(a)(3)(D) of the CAA, commenter 40 sa id. If EPA determines that requirements are necessary for remanufactured engines, the co mmenter (40) stated that EPA should first reevaluate previous conclusions made and make a finding that a new approach is necessary. The commenter (40) recognizes that section 202 of the CAA applies to mobile sources and that previous conclusions made by EPA are related to mobile engines, however, the commenter (40) believes the same conclusions should be applicable to stationary engine rebuilding practices. The commenter (40) also made the point that EPA has previously adopted emission standards, test methods and other requirements for stati onary engines where it modeled mobile source requirements for nonroad and marine engines. Subsequently, two commenters (37 and 40) recommended that EPA remove the last sentence of the definition and incorporati ng the following definition in the final rule: “Freshly Manufactured Engine means an engine that has not been plac ed into service. An engine becomes freshly manufactured when it is originally produced.”100 Commenter 40 argued similar points to co mmenter 37 (and also concurs with all comments submitted by commenter 37) stating that finalizing the definition as proposed would eliminate the positive benefits a ssociated with remanufacturing. The last part of the proposed definition would subject the remanufacturing proce ss to the same requirements that a new engine using entirely new parts is subj ect to, including certification, where applicable, the commenter (40) said. Consequently, the be nefits associated with a remanuf actured engine would be lost.

Response : EPA agrees that it is appropriate to not in clude the reference to previously used parts in the definition of freshly manuf actured engine in the final ru le. EPA does not wish to get newly manufactured engines mixed up with rebuil t and remanufactured engines. Consequently, EPA is finalizing the following definition in 40 CFR 60.4219 and 60.4248 of the final rule: “Freshly manufactured engine means an engine that has not been placed into service. An engine becomes freshly manufactured when it is originally produced.”

10.0 Miscellaneous

10.1 Comment : Two commenters (43 and 55) said that EPA should resolve currently outstanding issues related to in terpretation and implementation of 40 CFR part 60, subpart JJJJ, requirements in this final rulemaking. One commen ter (55) said that it has previously submitted to EPA a list of questions and issues 1 that need to be resolved eith er in the rule itself or through guidance material. The list of questions and i ssues were based partly on workshops commenters 43 and 55 participated in, which were design ed to help operators implement the rule requirements. The commenter (55) said that EPA needs to resolve these issues and referred back to the original March 10, 2010, letter for additio nal details on the issues. Commenter 43 stated101 similarly that it has also submitted a list of issu es to EPA over the last few years that need clarification, e.g., the commenter (43) submitted a letter to EPA in March 2008. The commenter (43) urged EPA to address these issues, ac knowledging that some of them may be most appropriately covered in guidance material, but that others should be addressed in the rulemaking

itself.

Response : The focus of the proposed amendments was on 40 CFR part 60, subpart IIII. EPA’s intention was not to make substantive changes to 40 CFR part 60, subpart JJJJ at this time. However, EPA took the opportunity under thes e proposed amendments to propose minor

clarifications and corrections to that subpart for consistency w ith 40 CFR part 60, subpart IIII. EPA is only promulgating non-substantive and mi scellaneous minor changes to 40 CFR part 60, subpart JJJJ under this final rule. EPA is current ly discussing other substantive changes to 40 CFR part 60, subpart JJJJ in a separate context.

10.2 Comment : Two commenters (43 and 55) said that the initial notification requirements in the SI NSPS need to be clarified, because cu rrent rules inadvertently imply that multiple notifications are necessary, which are burdensom e to operators. According to the commenter (55), 60.4230 defines the date that construction commences as the da te the engine is ordered, and 60.7(a)(1) requires notif ication of the date of constructi on within 30 days. This 30 day time period for initial notification is problematic, acco rding to commenter 55, for engine orders where siting or engine delivery does not occur within this time period, give n the definition in 60.4230. Additionally, the commenter (55) stated that op erators may feel obligated to submit initial notifications to multiple agencies, since an ordered engine could possibly be sited in one of102 several states. Thus, commenter 55 suggested that EPA clearly defi ne expectations and regulatory intent for notifications for the various parties involved (owner, operator, lessee, etc).

Response : As EPA has previously indicated, the focus of the proposed amendments was on 40 CFR part 60, subpart IIII, and EPA does not inte nd to address substantive changes to 40 CFR part 60, subpart JJJJ, aside from those intended to retain consistency with subpart IIII, in this proceeding. EPA will address these issues separately.

10.3 Comment : Two commenters (43 and 55) said that EPA should include concentration-based limits for engines between 25 HP and 100 HP in the SI NSPS. According to the commenters (43 and 55), engines in this size range will need to be tested in so me cases and having concentrationbased limits would provide a less costly complia nce options. The commenters (43 and 55) said

that the concentration-based limits should correspond to the g/HP-hr limits in 60.4233(d). For example, the 2.8 g/HP-hr would equate to 230 ppm by volume, dry basis of NO x at 15 percent oxygen based on the conversions used in Table 1 and 60.4233(f)(4) of the SI NSPS, the commenters (43 and 55) said.

Response : EPA agrees that it would be beneficial to include concen tration-based alternatives for engines between 25 HP and 100 HP that are subject to the SI NSPS. However, EPA would have to propose to add ppm standards to the SI NSPS as alternatives to the g/HP-hr standards first. EPA plans to do this in a separate proceeding.103 10.4 Comment : Two commenters (43 and 55) indicated that in Table 1 of 40 CFR part 60, subpart JJJJ, there are errors in the mathemati cal symbols for less than and greater than. For instance, “500 ≥ HP<1,350” should be corrected to “500 ≤ HP<1,350” and “25>HP<130” should

be corrected to “25<HP<130.” EPA should revi ew and correct the sym bols in Table 1 of 40 CFR part 60, subpart JJJJ, the commenters (43 and 55) said. These errors are important to fix, according to the commenter (55), because they result in duplicative re quirements for several engine size categories.

Response : EPA agrees with the commenters and has corrected the errors in the mathematical symbols that were previously incorrect in the rule.

10.5 Comment : Two commenters (43 and 55) said that EP A needs to address the fact that engine exhaust flowrate measurement is not required when conducting a compliance test for concentration-based standards. However, determin ing the flowrate is a re quirement in Table 2 of 40 CFR part 60, subpart JJJJ, and the commenters (43 and 55) recommended that EPA clarify that this determination is only necessary for engines complying with mass-based limits (i.e., g/HP-hr limits). The commenters (43 and 55) su ggested that EPA revi se Table 2, column 3, requirements (1)(a)(iii), (1)(b)(i ii), and (1)(c)(iii) to read: “If necessary (i.e., for compliance with ma ss-based emission standards, determine the exhaust flowrate of the stationary internal combustion engine exhaust.” Failure to address this minor revision, according to the commenter (55), will result in implementing agencies requiring unnecessary tests and incu rring associated costs.104 Response : EPA agrees with the commenter that it is appropriate to make this correction because taking a flowrate measurement is not needed for sources that are complying with the

concentration-based standards. EPA has made it clear in Table 2 of 40 CFR part 60, subpart JJJJ that determining the exhaust flowrate of the e ngine is not required when complying with the

concentration-based standards for NO x , CO and volatile organic compounds.

10.6 Comment : Two commenters (43 and 55) said that EPA should clarify in the final SI NSPS how sources should determine compliance with the NO x + hydrocarbons (HC) limits. For natural gas engines between 25 HP and 100 HP the ru le indicates that HC is assumed to be zero for performance tests for natural gas engines. The commenters (43 and 55) asked that EPA clarify that HC emissions can be assumed to be zero from natural gas emergency engines as well. If this is not the case, the commenters (43 a nd 55) said that EPA s hould clarify how HC is defined, i.e., which species should be in cluded and which should be excluded.

Response : As EPA has previously indicated, the focus of the proposed amendments was on 40 CFR part 60, subpart IIII, and EP A did not intend to make substantive changes to 40 CFR part 60, subpart JJJJ.

10.7 Comment : Two commenters (43 and 55) asked that EP A make clarifications in the final SI NSPS with respect to standards and time constraint s associated with import or initial installation of engines prior to 40 CFR part 60, subpart JJJJ a pplicability dates. Spec ifically, the commenters (43 and 55) thought that the langu age in 60.4236 is confusing where it uses “the previous model year” as opposed to “any previous model year” or “previous model years.” Commenter 55 said that it appears that paragraphs 60.4236(a) through (d) ar e supposed to provide 2 years from the105 initial applicability date for impor t or initial installation of an engine manufactured prior to the applicability date. However, the commenter (55) said, by using the language “the” previous year in section title, that literally means only engine s that are imported or installed within the prior year from the dates provided in 60.4236(a) thr ough (d), i.e., within a time period where the standard already applies. The co mmenter (55) also said the emissi on standard that applies is not clear and consequently recommended that EPA re vise the title of 60.4236 to state that it applies to “previous model years” and in the text, it should be clarified that the Stage 1 standards are the standards that apply under this section.

Response : EPA agrees with the commenter that cl arifying language related to the provisions limiting import and installation of engines past certain model years is appropriate. EPA

understands that the title of 60.4236 of 40 CFR part 60, subpart JJJJ was confusing and has consequently modified the title of that section. In the fina l rule, the title of 40 CFR 60.4236 reads as follows: “What is the deadline for impor ting or installing stationa ry SI ICE produced in previous model years?”

10.8 Comment : Two commenters (43 and 55) said th at the schedule fo r conducting initial compliance tests should be consistent with 40 CFR part 63, subpart ZZZZ requirements. Uncertified engines under the SI NSPS are required to conduct performance tests within 60 days after achieving the maximum production rate, and according to the commenter (55); this would typically be about 60 days after startup. Certified engines have up to 1 year to conduct the performance test under the SI NSPS and engine s subject to testing unde r the NESHAP have 180 days to perform the test. The commenters ( 43 and 55) were of the opinion that EPA should106 make the rules consistent and therefore recommen ded that the initial test for uncertified engines should be 180 days under the SI NSPS.

Response : EPA is not making substantive changes to 40 CFR part 60, subpart JJJJ at this time. Consequently, EPA will address the scheduling of performance test issue when other issues

related to the SI NSPS are de alt with at a later date.

10.9 Comment : Two commenters (43 and 55) said that the SI NSPS requires engines above 500 HP to test every 8,760 hours of operation or every 3 years. For engines that operate constantly, this equates to a test once a y ear, the commenters (43 and 55) sai d. However, the rule does not provide for a scheduling allowance, that historically, according to the commenter (55), testing requirements often include, e.g., within 30 days of the “due date.” The commenter (55) believes this adds complexity particularly for the engine s that operate around the clock and said that the annual date for conducting the test would move progressively forward every year. Commenters

43 and 55 felt that it is reasonabl e to allow a test schedule that remains constant over time, e.g., the test could be scheduled within 30 days of the annual anniversary, in order to reduce the scheduling burden and to account for issues rela ted to the ability to achieve “peak load,” maintenance downtime, test contractor availa bility, and so on. The commenters (43 and 55) recommended that EPA allow the yearly test to be conducted a certain window (e.g., 30 days) of the deadline triggered by 8,760 operating hours.107 Response : EPA is not making substantive changes to 40 CFR part 60, subpart JJJJ at this time. EPA will address the frequency and timing of performance testing at a later date when other

issues related to the SI NSPS are addressed.

10.10 Comment : Two commenters (43 and 55) are of the opinion that the SI NSPS should include a burn-in period for new, modified, reconstructed and rebuilt engines, consistent with the NESHAP. The commenters (43 and 55) indicated that the 200 hour engine burn-in period can prevent damage to the catalyst, which is possibl e during the initial engine operating hours. Not having this provision could lead to damage and premature failure of the catalyst, according to the commenters (43 and 55). The comm enters (43 and 55) also said that without this provision, equipment is run in a mode that can void em ission guarantees, significan tly increase control costs, increase waste streams from damaged cat alyst, and lead to unnecessary emissions.

Commenter 55 believes that it is not appropriate to compare stati onary engines to mobile source engines in terms of an engine burn-in period and according to the commenter (55), catalyst vendor recommend including a burn-in period to guara ntee proper catalyst performance and life. The commenters (43 and 55) urged EPA to include the same burn-in period allowance in the SI NSPS as was provided in the NESHAP because the same issues apply to units complying with either regulation. The commenters (43 and 55) recommended that the following specific language be added to the SI NSPS: “For new, reconstructed, modified, and re built stationary RICE, deviations from the emission or operating limitations that occur duri ng the first 200 hours of operation from engine startup (engine burn-in period) are not violations.”108 Response : EPA will address burn-in period issues re lated to the initial hours of operation for new engines with catalytic aftertreatment when EPA other issues related to the SI NSPS are

addressed.

10.11 Comment : Two commenters (43 and 55) said that EPA should define the terms “maximum engine power” and “peak load” in 40 CFR part 60, subpart JJJJ. The commenters (43 and 55) indicated that for engi nes less than 25 HP it is clear what the term “maximum engine power” means because the SI NSPS points to th e definition of the term in 40 CFR 90.3. However, for engines above 25 HP , commenters 43 and 55 said that it is unclear what maximum engine power means. Based on conversations the commenters (43 and 55) have had with manufacturers and operators of engines, it s eems that maximum engine rating should be the nameplate rating provided by the manufacturer, regardless of specific site conditions like elevation. However, the commenters (43 and 55 ) pointed out, the term “nameplating rating” does not have a clear definition either, and that te rm (or “engine rating”) should be clarified in 40 CFR part 60, subpart JJJJ also.

Response : EPA will address what the terms “maxim um engine power” and “peak load” mean when other substantive changes are made to 40 CFR part 60, subpart JJJJ. At this time, however, EPA is not making significant changes to the SI NSPS, but is only making minor corrections to the subpart while addressing substantive revi sions to 40 CFR part 60, subpart IIII.

10.12 Comment : Two commenters (43 and 55) asked th at EPA clarify what documentation is necessary under 60.4245(a )(3) of 40 CFR part 60, subpart JJ JJ for certified engines. The109 commenters (43 and 55) wanted to know what the operator is requi red to maintain in terms of documentation both where the certified engine is operated as certified and as non-certified.

Response : EPA will clarify the documentation requirements when other substantive changes are made to 40 CFR part 60, subpart JJJJ.

10.13 Comment : Two commenters (43 and 55) asked th at EPA revise 60.4233(f)(4) of 40 CFR part 60, subpart JJJJ to specifically indicate the implementation dates and emission limits that apply to the 500 HP to 1,350 HP subcategory of e ngines. The commenters (43 and 55) said that there is confusion regarding thes e engines that were manufactured from July 1 to December 31, 2007, that are modified or reconstructed. The commenters (43 and 55) specifically recommended that EPA add a new paragraph (iv) as follows: “(iv) Prior to January 1, 2008, for non-emerge ncy lean burn natural gas and LPG engines with a maximum engine power greater than or equal to 500 HP and less than 1,350 HP.” In addition, the commenters (43 and 55 ) asked that EPA revise paragr aph (i), which is for engines 500 HP and above, to exclude the engines that the commenters (43 and 55) are recommending be specifically addressed in a new paragraph (iv).

Response : EPA agrees with the commenters’ suggesti ons and has included a fourth paragraph in 60.4233(f)(4) of the final rule as we ll as clarified in paragraph (i) that the engines addressed in 60.4233(f)(iv) are not incl uded in 60.4233(f)(4)(i).110 10.14 Comment : One commenter (55) indicated that it supports EPA proposed revisions to 60.4243 of 40 CFR part 60, subpart JJJJ, to more clea rly identify the requirements that apply to certified engines and non -certified engines.

Response : No response is needed.

10.15 Comment : One commenter (55) expressed that it supports EPA posting a redline version of proposed changes to th e rule in the docket.

Response : No response is needed.

10.16 Comment : One commenter (37) urged EPA to pr ovide incentives for engines that are efficient under the CI NSPS. Specifically, th e commenter (37) recommended that EPA follow other rules such as the NSPS for steam generator boilers and stationary combustion turbines, and allow increases in criteria pollutant emissions for engines that are energy efficient. The commenter (37) argued that providing such an incentive for engines would highlight the importance of energy efficiency and reducing fu el consumption and greenhouse gas emissions. In addition, this would level th e playing field for engines that compete against boilers and turbines that currently can utilize energy effi ciency provisions under their NSPS, the commenter (37) said.

Response : EPA encourages energy-efficient engines, but providing incentives for stationary CI engines that are efficient is be yond the scope of this rulemaking. The standards as promulgated111 are feasible and EPA sees no reason to change the standards. EPA may consider making such accommodations for efficiency and lower greenh ouse gas emissions in the future when EPA

reviews the standard unde r 111(b)(1)(B) of the CAA.