UNITED STATES ENVIRONMENTAL PROTECTION AGENCY 

NATIONAL VEHICLE AND FUEL EMISSIONS LABORATORY 

 2000 TRAVERWOOD ROAD 

 ANN ARBOR, MI 48105-2498 

 OFFICE OF 

 AIR AND RADIATION 

January 10, 2014 

MEMORANDUM

SUBJECT: Summary and Analysis of Comments on Regulatory Amendments Related to 

Technical Hardship for Nonroad Diesel Engines and Replacement Engine 

Provisions for Nonroad Engines 

FROM: Alan Stout 

 Assessment and Standards Division 

TO: Docket EPA–HQ–OAR–2012–0102 

This document describes the comments received following the proposed rule, with various 

regulatory amendments. The comments identified are limited to those issues that we are 

addressing in a new final rule. These changes were reflected in a direct final rule, but were 

withdrawn based on the adverse comments received. 

The first table below describes the issues raised by North American Repower regarding the 

proposed changes to the replacement engine exemption. These comments are handled separately 

because they are so extensive. The following table addresses the range of additional comments 

from other commenters. 

Table 1 — North American Repower Comments 

Comment Response 

1) The proposed changes to 1068.240(c)3 [sic] are not 

related to alignment with NHTSA regulations, but as

stated in the preamble, are to address issues created by 

CARB regulations unrelated to new EPA GHG 

regulations. I do not believe this qualifies the proposed 

changes under the “good cause” exception clause of the 

Administrative Procedure Act as explained in the 

preamble. Placing these proposed changes into this 

“technical adjustment” direct final rule process for GHG 

regulations rather than the regular EPA regulation 

process denies stakeholders affected by these changes 

their proper due process. I understand the need to 

expedite a solution for the California diesel owners 

affected, but I believe EPA already has discretionary 

While the direct final rule depended on a “good cause” 

exception to the Administrative Procedure Act for the 

changes to §1068.240, this is not the case for this final 

rule, which follows from the proposal published at the 

same time as the direct final rule. The existing 

regulations do not give EPA authority to approve any of 

the proposed technical changes to §1068.240 on the 

basis of hardship or other factors. Moreover, we believe 

that authority for hardship relief by EPA should be

incorporated in the regulations only when it is not

possible to explicitly codify the necessary relief directly 

into the regulations, without need for a case-by-case 

determination by EPA. Explicit allowances provide 

certainty to the regulated community, while potential 
power under the “hardship” exemptions to provide these 

owners with needed relief, and should not use this 

technical amendment as the means to discuss these 

proposed changes. For this reason alone, I suggest that 

the proposed changes to 1068.240(c)3 [sic] be removed 

from the proposed regulations. 

hardship relief can cause uncertainty, since individual 

manufacturers would not know whether EPA would 

grant such relief to them or their competitors. We are 

proceeding with a new final rule to adopt changes to 

§1068.240 for the reasons described in the preamble and 

in our responses to these and other comments. 

2) I do not object to the all the changes proposed of 

1068.240, only paragraph 1068.240(c)(3)- [sic] 

(3) The old engine block may be reintroduced into 

U.S. commerce as part of an engine that meets either 

the current standards for new engines, the provisions 

for new replacement engines in this section, or another 

valid exemption. Otherwise, you must destroy the old 

engine block or confirm that it has been destroyed. 

This paragraph creates several issues and disregards the 

entire concept of “Designing for Sustainability”. Most 

notably, it ignores that all the emissions improvements 

in diesel engines over the past decades had nothing to do 

with the block, but with improved technologies attached 

to that block. The language displays a mindset that

arcane bookkeeping practices should dictate how 

emissions policy is created rather than sound 

environmental engineering principles. By destroying the 

block, a “dirty old diesel engine” is removed from the 

EPA ledgers, but the opportunity to re-use this valuable, 

useful and carbon intensive component in an advanced 

design engine currently in development, or with other 

technologies yet to be CARB or EPA certified (in 

exactly the fashion that all HD emissions improvements 

to date have been accomplished), is lost forever. 

We agree that an engine block can remain unchanged 

through multiple tiers of standards. However, it is not 

the case that any given engine block can be upgraded to 

the most recent tier of standards. When an engine 

manufacturer goes through a redesign process to create 

an engine block that serves as a new platform for 

meeting more stringent emission standards, the previous 

design of engine blocks are no longer suitable for 

upgrading to the newer standards. 

The proposed regulation allows reuse of replaced 

engines. It merely requires the engine to be covered by 

a certificate or qualify for an exemption. They can be 

upgraded to the point of being certified to current

standards, or they can qualify for the replacement engine 

exemption (as if they were new engines). Such engines 

may also be used if they qualify for a different 

exemption (export, display, testing, etc.). There is no 

requirement to destroy old engines. 

I am seeking clarification or changes to the following 

points: 

• If the OEM could currently remanufacture this engine 

to meet current emission standards, the replacement

motor issue would be rendered moot, and this “new”,

emissions current engine would be required to be 

installed per CARB regulations. If the limitation is that 

the current emissions configuration motor cannot fit 

now, destroying the block now leaves no room for this 

low carbon component to be used in a future certified 

configuration that does fit. 

For logistical and other reasons, it may be appropriate 

for the old engine to be replaced by a new engine even 

though the old engine may be suitable for restoration to 

a working configuration that would allow it to be sold as 

a certified engine or as a replacement engine meeting 

applicable provisions from §1068.240. Such a 

remanufactured engine could then be appropriately 

installed in a different piece of equipment, subject to 

certain limitations that depend on the circumstances. 

Under the new approach, there is no requirement to 

destroy old engines. 

• This language states that the block can be re-used to 

create a “new” replacement engine as defined in this 

section. But by definition, a “new” replacement engine 

is not an existing, used block, but a previously unused 

block, so this statement appears to state that EPA defines 

“new” as including engines made from used blocks. If 

this is the case, then again the changes to 1068.240(c)3 

[sic] are unneeded as this ‘needing to be replaced” 

engine could be rebuilt back to original specifications to 

satisfy CARB’s requirements. If the issue is that CARB 

and EPA have different definitions of “new”, then that 

issue should have been dealt with at the time CARB 

In section 216 of the Clean Air Act, Congress defined 

“new” for motor vehicles in a way that allowed for new 

engines to contain used parts. It defined “new” as 

follows: 

“Except with respect to vehicles or engines imported 

or offered for importation, the term ‘new motor 

vehicle’ means a motor vehicle the equitable or legal 

title to which has never been transferred to an 

ultimate purchaser; and the term ‘new motor vehicle

engine’ means an engine in a new motor vehicle or a

motor vehicle engine the equitable or legal title to 
applied to EPA for authority to institute their retroactive 

emissions regulations. In either case, this is a complex 

issue, and one that should have a full airing, and not be 

subject to EPA’s direct rule order. I propose that this 

issue be discussed in the correct venue, and that this 

language be retracted until a full airing with affected 

industry partners can be accomplished. 

which has never been transferred to the ultimate 

purchaser; and with respect to imported vehicles or

engines, such terms mean a motor vehicle and engine, 

respectively, manufactured after the effective date of 

a regulation issued under section 7521 of this title 

which is applicable to such vehicle or engine (or 

which would be applicable to such vehicle or engine

had it been manufactured for importation into the 

United States).” 

Thus whether the engine block or any other components 

of the engine have been used previously is irrelevant to 

determining whether or not the engine is new. This

definition prevents manufacturers from producing 

effectively new engines around old engine blocks to

circumvent Clean Air Act requirements. 

It is important to note that this definition is not a recent 

provision. It has been in place essentially unchanged 

since the Air Quality Act of 1967 (Pub. L. No. 90-148, 

81 Stat. 48). 

EPA’s pre-existing regulations clarify the definitions for 

“engine” and “new engine” and other relevant terms,

Under these pre-existing regulations, engine blocks are 

not considered engines. These definitions are not being 

revised in this rule. 

• “or another valid exemption.” This statement seems far 

too vague, presumably to give EPA leeway in granting 

permission to OEMs to utilize these blocks in other

environmentally compliant uses. However, as written, 

the statement appears to reference the 1068 section only, 

and no other valid exemptions are listed in this section. 

Presumably, uses such as conversion to an Alternative 

Fuel engine are meant to be allowed, but this language 

does not make this point clearly, but instead could

actually be interpreted to specifically deny it. 

We disagree that this is vague. The regulations in 40 

CFR part 1068 and the standard-setting parts describe a 

variety of very specific exemptions. EPA does not have 

authority to grant exemptions other than as specified in 

the regulations. Rather than listing those, the regulation 

draft simply states that all the regulatory exemptions are 

available for engines that have been replaced under the 

tracked option. The presumed exemption for alternative 

fuels is erroneous; since there is no such exemption 

specified in the regulation, a fuel conversion alone 

would not qualify as a “valid exemption.” On the 

contrary, existing regulations at 40 CFR part 85, subpart 

F, spell out specific provisions that apply for fuel 

conversions with engines used in motor vehicles. A fuel 

conversion with a replaced engine is not disallowed; 

rather, such an engine under the tracked option may be 

re-introduced into U.S. commerce subject to the 

qualifications noted above. It is not unreasonable to 

believe that remanufactured engines can be made to 

comply with current emission standards for heavy-duty 

highway engines or for nonroad spark-ignition engines 

above 19 kW, whether they use gasoline or natural gas. 

Current 1068.240(c)3 [sic] regulation states that the 

OEM or its Agent take possession of the block, and the 

block can be used in any current EPA compliant fashionby an OEM or another entity. The current language is 

very clear, the proposed language is not. This new 

language adds no further protection to the environment, 

but instead makes destroying a carbon intensive resource 

The regulatory provisions in place for the last several 

years have required the certificate-holding engine 

manufacturer to take possession of the old engine or 

confirm that it has been destroyed. It is not clear why 

the commenter believes this would allow for different 

companies to use such engine blocks to build working 

engines. The old language neither states that the “block 
the default action for blocks that cannot be immediately 

remanufactured into one of the two defined 

configurations. I propose that the current language

should remain in force, and the proposed language 

should be dropped from consideration. 

can be used in any current EPA compliant fashion” nor 

does it mention other entities. The new language is 

actually more accommodating in this regard, since the 

verb form allows for a company other than the certifying 

engine manufacturer to sell the engine (which presumes 

that the engine manufacturer sells the engine to the other 

company under the exemption provisions of §1068.262). 

Since there are generally viable alternatives for building 

up the old engine block into a cleaner engine, we 

disagree that destroying the old engine is the default 

action. 

We have confirmed with engine manufacturers that they 

routinely take possession of these old engines, or 

confirm that they have been destroyed, so it is not clear 

how North American Repower’s current practices would 

be affected by this provision in any form. 

• The proposed language for 1068.240(c)3 [sic] makes 

no provision for technologies still coming to market that 

could utilize these used blocks in an EPA or CARB 

compliant use, or for use by non OEMs in a compliant 

and sustainable manner. This is in direct conflict with 

EPA’s policy of encouraging Manufacturing for 

Sustainability. EPA has recently created clear 

regulations on converting engines to Alternative Fuels, 

and the current administration has repeatedly publically 

stated that moving to alternative fuels is a priority, and 

has created economic incentives to lower the economic 

barrier for adoption of this technology. Utilizing existing 

in use engines, remanufactured to an EPA compliant or 

CARB certified alternative fuel configuration, is the 

lowest carbon pathway as well as the most economically 

advantageous path to moving to alternative fuels for end 

users. Currently no OEMs have an EPA or CARB 

certified or compliant Alternative Fuel Heavy Duty 

Engine conversion product. Therefore the OEM’s will

be forced to destroy these blocks rather than allow them 

to be available for development into an Alternative Fuel 

compliant solution, even if they have such a program in 

development now or in the near future, or if a non OEM 

has such a program. 

This comment is unfounded. The proposed language 

specifically contemplates producing certified engines 

from recovered engine cores. There is also provision to 

build engine cores into working engines that are less 

than a certified configuration, subject to the conditions 

that apply under the replacement engine exemption (or 

any other exemption). These provisions apply whether 

the modified engine runs on a conventional or 

alternative fuel. 

Also, as described above, engine cores recovered from 

tracked replacement engines generally do not find their 

way to non-OEM rebuilders. 

• Current 1068.240(c)3 [sic] language allows OEMs to 

place the used block into a well-established 

remanufacturing materials stream such that these blocks 

are available for non OEM technology providers to 

create EPA compliant products, both now and in the 

future. The proposed language mandates that only the 

OEM be allowed to reintroduce the block into 

commerce, potentially creating a monopoly over this

valuable resource. If the argument is that this mandate to 

destroy the block only applies to a very few coming

from the California applications affected, and plenty of 

like design used blocks can be sourced to fulfill the non 

OEM need, then what is the point of destroying these 

few blocks if like design blocks are otherwise allowed 

As noted above, the commenter is mistaken in its belief 

and we believe the proposed language related to 

disposition of engine cores under the tracked option for 

replacement engines is actually more accommodating in 

accounting for third-party remanufacturers than the

earlier language. We believe the manufacturer 

benefitting from the replacement engine exemption to 

produce a new exempt engine has a clear responsibility 

to manage the disposition of the old engine core. 

There is no requirement to destroy old engines. The new 

approach describes how engines may be re-introduced

into commerce if they can be certified to current 

standards, or if they qualify for an exemption. One of 

the new conditions on the replacement engine exemption 
back into commerce through other channels? I do not

believe creating a market monopoly, or establishing

regulations that have no true effect other than to 

complicate doing business is the intention of EPA, and 

so I propose that the language should be retracted. 

is that the replacement engine has emission control

representing the cleanest available technology for the 

given application. Allowing unlimited use of the engine 

cores to serve as replacement engines without this 

requirement could lead to a perpetual use of these 

dirtiest engines in the fleet. 

We affirm the commenter’s observation that engine 

cores coming out of the tracked option of the 

replacement engine exemption would represent a small 

portion of the overall market of restoring engine cores. 

Engine cores might become available most readily from 

retiring equipment models. In any case, we believe the 

regulation will not substantially limit third-party

remanufacturers from being able to access engine cores 

for producing remanufactured engines. 

• The proposed 1068.240(c)3 [sic] language now places 

a burden upon the OEM to identify returned blocks of 

1068 replacements separately from other returned engine 

cores. Absent a current ability to make this block into a 

current emission standard diesel engine, the OEM must 

destroy this block or risk being non-compliant. The

OEMs are very risk adverse, to the point that they are 

unwilling to comment on this proposed language for fear 

of having their remanufactured products become a target 

for further EPA regulation. Because of this risk-averse 

regulatory culture, it is apparent that a far higher number 

of engine blocks will be destroyed than intended for fear 

of being out of compliance. Again, this may make the 

accounting end of EPA feel they are making inroads into 

improving the environment, but the reality is that 

environmentally irresponsible behavior is being 

encouraged. This a great waste of carbon already 

invested into a re-usable component, an expenditure that 

should be viewed as an investment into long lived and 

continuously improved products, not a onetime 

disposable use. 

The new approach is no different than what has applied 

for many years in that the engine manufacturer has the 

sole responsibility to manage the disposition of the old 

engine. Before and after this change to the regulations, 

manufacturers must either destroy the old engine or take 

it into their possession; once the manufacturers possess 

the old engine, applicable regulations regarding engine 

rebuilding and replacement determine how the engines 

may be re-used. Thus the proposed amendments do not

affect the manufacturers’ burden. 

• There is no language in the proposed 1068.240(c)3

[sic] paragraph that mandates the destroyed blocks be 

disposed of in an environmentally sound manner. This 

potentially adds to the waste stream in an 

environmentally irresponsible manner. I do not believe 

this to be the intent of the regulations, but is truly an 

unintended consequence that has direct negative 

environmental impact. The used engine blocks should be 

viewed as a valuable resource, one that should be 

accompanied by responsible stewardship. Without the

economic incentive of the block having value as an 

usable engine component, the cost of cleaning, 

transporting and placing a solo unusable block into a 

recycling stream will often be greater than its scrap 

value, and the block will enter the solid waste stream at 

best. Current language states that the OEM or its Agent 

take possession of the old block, which clearly places 

responsibility for the block on these entities as to its 

As described above, we believe the commenter 

fundamentally misunderstands both the old and the new 

regulatory provisions, since the new language is actually 

somewhat more accommodating than the old with 

respect to the role of third-party remanufacturers. 

Also as described above, we believe there should be

reasonable limits or conditions on using recovered 

engine cores to build remanufactured engines. We also 

believe that the proposed conditions are not restrictive to 

the point that large numbers of engine cores will need to 

be destroyed as a result of regulatory requirements. 

Beyond these qualifying conditions governing 

remanufacturing of engine cores, neither the existing 

regulations nor the revised regulations specify disposal 

requirements, and it is therefore beyond the scope of this 

final rulemaking to specify disposal requirements. 
final disposition. The proposed language merely states 

that (the OEM) “destroy the old block, or confirm that is 

has been destroyed”. This language is vague as to 

responsibility over final disposal of the destroyed block 

and offers the public no protection from irresponsible 

disposal. I believe the proposed language should be

retracted and current language should remain in force as 

it offers superior environmental protection assurances. 

Current market forces and existing EPA and CARB 

regulations already dictate OEM’s behave in an 

environmentally sound manner in returning these high 

carbon value components to compliant uses either now, 

or in the future. Because of this potential value alone, 

used blocks are currently entered into a very effective 

materials management stream that guarantees at a 

minimum these blocks will be part of the scrap metal 

recycling stream. The proposed language destroys this 

capability and sets a precedent that EPA seemingly 

prefers this carbon intensive component be turned into 

waste. By destroying these blocks, EPA increases the 

number of blocks that must forged new, generating GHG 

unnecessarily. Considering that most engine block 

foundries in the US have been closed, we are also 

looking at the additional GHG needed to bring this 

component to the US, and are essentially exporting our 

GHG pollution to offshore foundries. I do not believe 

this to be the intention of EPA or the policy of the 

current administration. 

• “you must destroy the old engine block or confirm that 

it has been destroyed.” There is no definition of 

“destroyed” provided in this section. The OEMs, the

Remanufacturing Industry and Alternative Fuel 

Conversion entities have long believed that complete 

disassembly of an engine constituted destruction, and 

that when a block was used to make a 

rebuilt/remanufactured/converted engine, its identity was 

based upon the EPA emissions family specification to 

which it is when newly built. This belief is based upon 

EPA’s definition of an engine’s original date of 

manufacturing being the date the original crankshaft is 

placed into the block. The belief is that the converse 

must also be true, that by removing the original 

crankshaft and all the other parts, the block loses its 

identity as a unique EPA specified engine and simply 

becomes an engine component. Support for this 

definition can be found in EPA engine labeling removal 

regulations (40 CFR 1068.101): 

(7) Labeling. (i) You may not remove or alter an emission 

control information label or other required permanent label 

except as specified in this paragraph (b)(7) or otherwise 

allowed by this chapter. Removing or altering an emission 

control information label is a violation of paragraph (b)(1) of 

this section. However, it is not a violation to remove a label in 

the following circumstances: 

(A) The engine is destroyed, is permanently disassembled, or 

Any conventional definition of “destroy” leaves no 

doubt that a destroyed engine block can never be used to 

create a remanufactured engine. A destroyed engine is 

one that has value only as scrap metal. To suggest that 

merely removing an engine’s identity equates to being 

destroyed is an improper interpretation of the plain 

meaning of the word. As for crankshafts, being 

“unborn” is clearly not the same as being destroyed. 

The referenced regulatory provision reinforces this by 

stating that destruction, disassembly, and other losses of 

identity are separate paths toward nullifying the original 

engine title. 

Moreover, there is no requirement to destroy old 

engines. We understand that manufacturers will in some 

cases destroy engine cores rather than using them for 

remanufacturing, consistent with economic and 

environmental considerations. This is no judgment 

against the old engines, but rather a recognition that 

there will be cases in which economic or environmental 

considerations will lead to the conclusion that the engine 

core should not be used to produce a remanufactured

engine. 

The regulation does not prevent engine cores from 

participating in technology development. To the 

contrary, the regulation specifically accounts for engine 

manufacturers applying new technologies to produce 
otherwise loses its identity such that the original title to the 

engine is no longer valid.

Recent personal communications with EPA staff have 

made it clear that EPA defines engine/block destruction 

as permanently altering the block so it cannot in any 

manner be placed back into service- a very different 

definition. The forced discarding of an engine block by 

mangling it for being guilty of being originally 

manufactured with old fuel management and emissions

technology is absolutely counterproductive to the stated 

goals of the GHG regulations. Eliminating these older 

blocks from an ability to participate in new technology 

development and product introduction by OEM and nonOEM technology providers is also counter to EPA, 

CARB and the Obama Administration’s goal of moving 

to lower carbon footprint vehicles and fuels. I do not 

believe this to be the intended goal of the EPA with this 

language, but it is a very real unintended negative

consequence, and it should be retracted. 

remanufactured engines from these engine cores. 

• EPA’s stated goal with this paragraph is to prevent 

older engines from being re-introduced to commerce in 

new equipment. This should be attained effectively by 

other provisions in 1068 and by other current CARB and 

EPA regulations, and therefore this paragraph which

mandates environmentally irresponsible behavior is not 

necessary. If other current regulations are not sufficient 

to prevent introduction of dirty engines into new 

equipment, then those regulations need to be addressed, 

not this piece of 1068.240. 

 We have determined that this is an appropriate 

approach to limit the reintroduction of these engines into 

service. While the commenter speculates that better 

alternatives exist, it does not provide any such examples 

that we can consider. 

• Remanufacturing of existing blocks right here in the 

USA not only reduces GHG emissions, but also provides 

Green Jobs- a priority of the current administration. The 

flawed MIT study, which completely ignored the carbon 

intensity of metal product production from ore outside or 

inside the USA, and the GHG’s generated by the current 

transport chain of raw materials and whole goods for 

engine block creation, also ignored the impact of new 

technologies coming to market to move existing diesel 

engines to run on Natural Gas, including renewable 

Natural Gas, in an emissions compliant fashion. This 

study should not be used to judge the effectiveness of 

the remanufacturing process as it applies to diesel

engines as it ignores the very history of emissions

technology development in the US. CARB and EPA 

instituted engine emission standards after the Clean Air 

Act passed prior to the technology existing which could 

meet these standards. This practice continues to this day 

with new standards being created, and Technology 

providers responding by developing the needed 

technology. Eliminating engine blocks which are 

Designed for Sustainability, and could potentially be 

used to create emission compliant engines meeting 

current or future emission standards, is poor GHG, 

environmental and economic policy. 

We agree that jobs are important and believe that reuse 

of these engines will be the same or greater under the 

new language. 
Just because a technology may not be certified now,

doesn’t mean it won’t ever exist to allow a low carbon 

footprint Heavy Duty Engine be sold into commerce that 

meets all emissions requirements, including the use of 

low carbon fuels. Mandating destruction of diesel engine 

blocks because the technology is not currently certified 

that can use these components in an environmentally

sound manner is short sighted, and I believe not the 

intention of the proposed amendment. Please remove the 

proposed 1068.240(c)3 [sic] language from the direct 

rule regulation and please keep the current language in 

force. 

There is no requirement to destroy old engines, and the 

regulation does not prevent engine cores from 

participating in technology development. 

 
Table 2 — Other Comments

Topic Comment Response 

TPEM/technical 

hardship 

(§1039.625) 

Toyota: Regulation should allow for 

technical hardship relief for vertically 

integrated companies 

The intent of the technical hardship provision is to help 

equipment manufacturers who are unable to accelerate 

or otherwise manage the engine development effort 

required to meet new emission standards. It would 

therefore be inappropriate to extend technical hardship 

to equipment manufacturers that source their engines 

from within the same company. We are not changing 

the regulation to address this concern. 

TPEM/technical 

hardship 

(§1039.625) 

MECA/CARB: Changes are 

problematic and unreasonable; EPA 

should require manufacturers getting 

extra relief to recover the lost 

environmental benefit. 

We have narrowed the scope of the proposed expansion 

to address these concerns. 

The hardship is conditioned on the equipment 

manufacturer not being at fault, so it would not be

appropriate to require additional control to make up for 

the relief. Moreover, equipment manufacturers don’t 

certify engines, so there is no ready mechanism to 

make changes that would compensate for using higheremitting engines. We are not changing the regulation to 

address this concern. 

Removing sales 

limits on FEL 

caps 

(§1039.104) 

MECA/CARB: Allowing greater 

numbers of engines certified to higher 

FEL caps raises concerns about local 

exposure to higher emission 

concentrations. The commenters also 

noted that it was unclear that this 

change was necessary for any 

particular engine manufacturer. 

John Deere: Described their need for 

relief from the FEL caps for one of 

their engine models. 

We have no reason to believe that the NOx and PM 

emission levels at the higher FEL cap will pose any

measureable increase in health risks. Manufacturers 

will need to account for the increased FELs with other 

engines that have FELs below the standard. We have

narrowed the scope of the proposal to more carefully 

address the technical issues identified by John Deere, 

but are otherwise not making changes to address the

concern about increased local exposures. . 

Replacement 

engines 

(§1068.240) 

CARB/NESCAUM: Supports the 

overall intiative to allow for strategic 

upgrades of used engines to facilitate 

turnover to cleaner engines. 

We are finalizing these provisions to accomplish this 

policy goal. 

Replacement 

engines — 

disposition of 

used engines 

(§1068.240) 

Peter Ward: Objects to limitations on 

the disposition of replaced engines.

We believe the limitation on the re-use of old engine 

blocks is necessary and appropriate to avoid 

circumvention of emission standards and other 

regulatory requirements. See the responses to North 

American Repower’s more detailed comments on this 

topic. 

Replacement 

engines—25-

year limit 

(§1068.240) 

CARB: CARB does not oppose the 

25-year limit but will not adopt it for 

California because California’s 

regulations require fleet 

modernization well ahead of the 25 

year limit.. 

National Groundwater Association: 

We are changing the 25-year limit to 40 years to 

address the concerns expressed in the comments. It is 

true that this limit does not apply for 

engines/equipment regulated by California ARB. 
The 25-year limit is an arbitrary rule 

that imposes economic hardship on 

companies that drive heavy equipment 

short distances; many times their 

expensive drilling rigs ($500,000+) 

are more than 25 years old. 

National Groundwater 

Association— supplemental 

comments: Changing to a 40-year 

limit would be a reasonable approach. 

Construction Industry Air Quality 

Coalition: Objected to the 25-year 

limitation and observed that this limit 

should not apply to engines/equipment 

regulated by California ARB.

NESCAUM: Supports disallowing the 

replacement engine exemption for 

equipment that is more than 25 years 

old. 

Replacement 

engines—vs. 

rebuild 

requirements 

(§1068.240) 

Hogan Lovells: Suggests adding 

language to clarify that the limitations 

on the disposition of replaced engine 

apply only if the replacement engine is 

new. They also request confirmation 

that the new provisions to have no 

bearing on EPA’s engine rebuilding 

program. 

We have modified the regulation to clarify the 

circumstances in which the restrictions apply for the 

engine being replaced. 

The commenter is correct that rebuilding provisions

continue to apply as described in §1068.120.