Comment: Commenters argued that contaminant concentrations found in
``off-spec used oil'' is comparable to traditional fuels. While
commenters submitted studies that looked at both on-spec and off-spec
used oil to support this assertion, Table 4 only summarizes data
presented in the comments on the contaminant levels in off-spec used
oil as compared to fuel oil and coal. In U.S. Study 1, 55 samples were
collected ``throughout the USA'' from facilities that combust used oil
in space heaters and/or small boilers. Two of the 55 samples were off-
spec; one was off-spec for total halogens and the other was off-spec
for cadmium. The researchers identified the off-spec used oil for total
halogens was an industrial oil that contains non-hazardous chlorinated
paraffin and the other was from a military operation. Table 4 presents
the data on the two samples that were off-spec. In the U.S. Study 2,
researchers looked at a database of used oil samples maintained by a
national commercial laboratory. The database contained over 3,500 used
oil samples from the U.S. and other countries on which over 17,000
analyses were performed from 2008 to present. Between 24 and 53 samples
in this dataset exceed the specification for one of the contaminants--
specifically for total halogens and chromium. The researchers
speculated that the high levels of halogens were due to non-hazardous
chlorinated paraffin which is used (added to the oil by lubricant
manufacturers) in industrial oils designed to encounter high pressure.
The researchers did not speculate on the reasons for the high levels of
chromium. Table 4 presents the data on the off-spec samples, only. In
the Canadian study, 230 samples of used oil were collected from various
businesses in Ontario, Canada between 2003 and 2010. Of those samples,
four were off-spec for arsenic, but not by significant amounts. The
commenters did not speculate on the reasons for the high levels of
arsenic. Table 4 presents the results of the analysis of the four off-
spec samples.

                 Table 4--Contaminant Concentrations in Off-Spec Used Oil and Traditional Fuels
----------------------------------------------------------------------------------------------------------------
                                                       U.S.        U.S.      Canadian     Fuel oil
                     Material                         study 1     study 2      study    No. 1,2,4,6   Coal \113\
                                                       \109\       \110\       \111\       \112\
----------------------------------------------------------------------------------------------------------------
 Samples.................................           2       24-53           4      Unknown     Unknown.
Year..............................................        2010        2010   2003-2010      Unknown     Unknown.
Containment Concentrations:
    Total Halogens (ppm):
----------------------------------------------------------------------------------------------------------------
        Minimum...................................       2,700          NR        42.2         <500       13,140
        Maximum...................................       6,170          NR       151.0
        Median....................................       4,435       6,642        80.5
        Average...................................       4,435       9,409        88.6
----------------------------------------------------------------------------------------------------------------
    As (ppm):
        Minimum...................................        <1.0          NR         5.1         <2.3     1.0--120

        Maximum...................................        <1.0          NR         6.7
        Median....................................        <1.0        <1.0         6.1
        Average...................................        <1.0        1.95         6.0
----------------------------------------------------------------------------------------------------------------
    Cd (ppm):
        Minimum...................................        0.30          NR       <0.92         <1.2     0.2--5.0
        Maximum...................................        2.60          NR          <1
        Median....................................        1.45        0.13        0.97
        Average...................................        1.45        0.69        0.97
----------------------------------------------------------------------------------------------------------------
    CR (ppm):
        Minimum...................................        <4.0          NR        <1.2         <2.3      1.0--90
        Maximum...................................        <4.0          NR         2.2
        Median....................................        <4.0        16.0         2.0
        Average...................................        <4.0        20.9         2.0
----------------------------------------------------------------------------------------------------------------
    Pb (ppm):
        Minimum...................................          14          NR        <4.6         7-57      0.5-0.9
        Maximum...................................          15          NR        17.0
        Median....................................          15        11.0         5.6
        Average...................................          15        35.2        8.2
----------------------------------------------------------------------------------------------------------------
NR = Not Reported.

    EPA's Response: While data was submitted regarding higher levels of
contaminants in coal than in off-spec used oil, coal is not an
appropriate comparison for used oil since some combustion units that
burn used oil can alternatively only burn fuel oil and not coal (such
as space heaters). Thus, used oil should be compared to fuel oil. The
specifications promulgated under 40 CFR 279.11 were developed by
looking at contaminants in fuel oil and the risks posed by those
contaminants. The data submitted states that the average total halogen
content of off-spec used oil from one study is 9,409 ppm (with the on-
spec concentration of 4,000 ppm maximum). Also, off-spec used oil
contains as much as 21 ppm of Cr, on average, (with the on-spec
concentration of 10 ppm maximum). Thus, off-spec used oil does not meet
the legitimacy criterion for contaminants.
---------------------------------------------------------------------------

    \109\ Source: EPA-HQ-RCRA-2008-0329-0799.2
    \110\ Source: EPA-HQ-RCRA-2008-0329-1273.1 Attachment B
    \111\ Source: EPA-HQ-RCRA-2008-0329-0799.4
    \112\ Source: EPA-HQ-RCRA-2008-0329-0799.2, EPA-HQ-RCRA-2008-
0329-1273.1, Attachment B
    \113\ Ibid.
---------------------------------------------------------------------------

    When EPA created the specification levels set in 40 CFR 279.11, it
identified those levels as being comparable to fuel oils. EPA maintains
that these levels are appropriate standards to measure what should and
should not be burned in CAA section 112 and 129 units. Thus, off-spec
used oil (those oils that do not meet the specification levels set in
40 CFR 279.11) is deemed to have more contaminants than fuel oils
produced for burning and, therefore, are a solid waste.
    Comment: EPA is ignoring the fact that the level of contaminants in
a secondary material is not dispositive of whether or not a secondary
material is a waste. It is merely an indicator of whether or not EPA
should look more closely at the recycling activity when making the
waste determination. Levels of contaminants only insignificantly higher
than those found in traditional fuels hardly imply a purpose of
disposal, assuming the secondary material being combusted is otherwise
a valuable fuel. Only when a material contains contaminants at
significantly elevated levels does it begin to become reasonable to
presume that there may be an intention to discard.
    EPA's Response: We agree that contaminant levels are an indicator
of waste activity and we have investigated the case of off-spec used
oil to fully assess if its use in a combustion unit is truly a waste
activity. As a result of our investigation, it is clear from the data
in Table 4 that off-spec used oil does not contain comparable levels of
contaminants to fuel oils.
    Comment: In the context of determining whether a hazardous
secondary material is a solid waste, EPA recognizes that legitimate
recycling can occur even if the material has higher levels of toxics
than virgin materials. To show this, the comment cites a discussion by
the Agency in an earlier rule in which foundry sands are reused for
mold making in a facility's sand loop. The comment argues that it is
relevant that the sands used to make the molds may have significantly
higher concentrations of hazardous constituents than virgin sand.
However, because the sand is part of an industrial process where there
is little chance of the hazardous constituents being released into the
environment or causing damage to human health and the environment,
these levels would not affect the legitimacy of the recycling process.
    EPA's Response: EPA disagrees with this comment. In the first
place, the Agency is not reopening its hazardous waste regulation.
EPA's identification of the legitimacy criteria is based on the record
for today's action, and does not address hazardous waste. In any event,
the discussion of foundry sand contamination, even though it would be a
hazardous waste without application of the legitimacy criteria for that
rule, presents what appears to be a vastly different recycling
situation. In this rule, combustion will result in releases to the air.
This is why the rule calls for restrictions on burning. The foundry
sand example is a closed loop system and is not implicated by
contamination problems that releases lead to the atmosphere. We would
also note that in a March 28, 2001 letter from Elizabeth Cotsworth,
then Director of the Office of Solid Waste and Eric Schaeffer, then
Director of the Office of Regulatory Enforcement to Amy Blankenbiller
of the American Foundry Society, we also discussed the use of foundry
sand as part of the sand loop for mold-making being part of a
continuous industrial

process.\114\ However, the letter also made clear that the letter did
not address the thermal processing of sand, which would be a combustion
unit, and would be more equivalent to a scenario that is addressed in
today's final rule.
---------------------------------------------------------------------------

    \114\ A copy of this letter can be found in the docket to
today's rule.
---------------------------------------------------------------------------

    Comment: Commenters argued that processing of off-spec used oil is
contrary to the goals of energy efficiency and wise resource
utilization. They argued that the rule should continue to allow/follow
the rules set forth in 40 CFR 279.11 as it pertains to used oil as a
viable and not discarded fuel. That is, if off-spec used oil is blended
with virgin oil or on-spec used oil to meet the 40 CFR part 279 used
oil specs, the resulting oil should be considered a legitimate fuel
product.
    Other commenters argued, however, that when these materials are
distilled into fuel, they are still wastes, regardless if they have
been blended or processed to obtain an on-spec material. Wastes are
always wastes and their status cannot be changed through simple
processing.
    EPA's Response: Whether or not processing of used oil is contrary
to the goals of energy efficiency, off-spec used oil contains more
contaminants than traditional fuels, and thus, is not a traditional
fuel. In addition, as we have stated previously, the regulations at 40
CFR part 279 do not discuss or address whether used oil has been
discarded, as commenters have claimed, but rather ensure that used oil
that is recycled is conducted in a manner that protects human health
and the environment. To that end, we encourage, and the RCRA used oil
regulations currently allow, the processing of off-spec oil to create
on-spec used oil as per 40 CFR 279.50, which states that processing
``includes, but is not limited to: blending used oil with virgin
petroleum products, blending used oils to meet the fuel specification,
filtration, simple distillation, chemical or physical separation and
re-refining.'' There is nothing in today's rule that would change this
requirement.
    We also disagree with commenters that processing of off-spec used
oil into on-spec used oil still renders it a waste. EPA's regulations
at 40 CFR 279.11 state that, once oil is determined to be on-
specification in accordance with the regulations in Part 279, the used
oil regulations do not apply to the material. On-specification used oil
is for all intents and purposes the same as oil refined as a product
fuel in the first instance and the Agency is not reopening its 40 CFR
part 279 regulations.
    Comment: Commenters argued that used oil, particularly from
automobiles, is on-specification and facilities that burn automobile
oil should be allowed to burn them under CAA section 112, along with
other on-spec used oil. Comments base this determination on the
elimination of leaded gasoline. Commenters also supplied studies to
support this assertion.\115\
---------------------------------------------------------------------------

    \115\ See documents EPA-HQ-RCRA-2008-0329-0799; EPA-HQ-RCRA-
2008-0329-1273.1; EPA-HQ-RCRA-2008-0329-1686.
---------------------------------------------------------------------------

    EPA's Response: The data provided in the comments indicates that a
very small portion of used oil is off-spec. Assuming the data is
representative of used oil, most used oil will be an alternative fuel
(within the definition of a traditional fuel). This does not allow us
to make a broad classification that, because only a small portion of
used oil is off-spec, used oil can be generally classified as on-spec.
On the other hand, the data in the studies submitted by commenters
indicate that used oil obtained from small, private automobiles
serviced by DIYers and auto repair shops will be on-spec, which would
not be a solid waste. In addition, as we describe elsewhere in today's
preamble, persons can submit a non-waste determination petition if they
believe that their used oil is not a waste.
    Comment: Many commenters stated that there are numerous auto repair
shops that use used oil to fuel their space heaters, which do not (or
would not likely) meet the air pollution controls required by the CAA
section 129 standards. The commenters argue that such auto repair shops
will no longer be able to use off-spec used oil in their space heaters
if off-spec used oil is determined to be a solid waste.
    Moreover, commenters assert that auto repair shops will likely not
want to take on the additional burden of testing the used oil to
determine if it is on-spec in order to use some portion of the material
in their space heaters without having to comply with the CAA section
129 standards. They further assert that these shops may illegally
dispose of used oil if they cannot burn it in their space heaters and
they are not located near a processor. Commenters expressed concerns
that they may also stop collecting used oil from individuals who remove
their own used oil (do-it-yourselfers, or DIYers) as they have no
incentive to take the DIYers oil, which may lead to DIYers illegally
disposing of their used oil.
    EPA's Response: In this rule, EPA determined whether off-
specification used oil is a solid waste. However, EPA's regulations
promulgated today under CAA 129 do not apply to space heaters. Thus,
today's rule would not in any way change the current regulatory scheme
or operations for burning of used oil in space heaters since the Agency
is not promulgating emission standards for such units.
    In particular, EPA is specifically clarifying in this final rule
that used oil combusted in an oil-fired space heater that meets the
provisions of 40 CFR 279.23 need not be tested to establish whether or
not such oil is on or off-spec. This includes used oil generated by
small facilities such as auto repair shops and machine shops that have
such units, and used oil-generated by homeowners who change their own
oil (referred to as ``do-it-yourself'' or ``DIY'' oil) that are burned
in such units. This is because the CISWI regulations promulgated
elsewhere in the Federal Register today do not establish emissions
limits for such units, and therefore the concerns of the commenters
that such units would have to comply with CAA Section 129 standards
have been addressed for this population of combustion units.
    EPA also points out that anyone wishing to show that the material
is on-spec does not have to test the used oil, but can use other
information besides analyses. Specifically, the existing regulation
under 40 CFR 279.72 states that used oil fuel can be determined to be
on-spec by ``performing analyses or obtaining copies of analyses or
other information documenting that the used oil fuel meets
specifications.''
8. Coal Refuse \116\
---------------------------------------------------------------------------

    \116\ The proposed rule differentiated between coal refuse and
mined landfill ash. For a discussion regarding the use of mined
landfilled ash as a fuel, see the coal combustion residuals section
for fuels (Section V.B.9); for a discussion regarding the use of
these non-hazardous secondary materials as ingredients, see the coal
combustion residuals section for ingredients (Section V.C.2).
---------------------------------------------------------------------------

    Coal refuse refers to any by-product of coal mining or coal
cleaning operations. Coal refuse is generally defined by a minimum ash
content combined with a maximum heating value, measured on a dry basis.
Coal refuse consists primarily of non-combustible rock with attached
coal that could not be effectively separated in the era in which it was
mined. Due to advances in coal preparation technology over the past
century, the processing of coal has evolved such that materials that
are now generated in the coal mining process, which would have been
considered coal mining rejects in the past and discarded in waste
piles, are now handled and

processed as coal. In the early twentieth century, coal preparation
involved simple size segregation into lump coal for domestic use and
intermediate-sized coal for industrial use. Coal fines were considered
unfit for use and were disposed of as mine rejects in discarded coal
refuse piles. Today, however, coal preparation plants are much more
capable of separating coal from mineral matter through processes, such
as density separation and froth flotation.\117\
---------------------------------------------------------------------------

    \117\ See National Research Council of the National Academies
(NRC), ``Coal Research and Development,'' 2007, accessed on May 14,
2008 at: http://www.nap.edu/catalog.php?record_id=11977. See
generally ``Materials Characterization Paper on Coal Refuse,'' a
copy of which is included in the docket for today's rulemaking.
---------------------------------------------------------------------------

    Thus, the proposed rule differentiated between coal refuse that is
currently generated and coal refuse that was generated in the past and
placed into ``legacy'' piles. The proposed rule considered coal refuse
that is currently generated and used as a fuel as not being abandoned
or disposed of and, therefore, is not considered a solid waste. On the
other hand, the proposed rule stated that coal refuse placed in legacy
piles has clearly been discarded, thus meeting the definition of a
solid waste material. With regard to coal refuse from legacy piles, the
proposed rule described the processing of this non-hazardous secondary
material as involving separation through the use of screens or
grizzlies, blending, crushing, or drying. Although we understand that
virgin coal is similarly processed, the proposal stated that the Agency
believes that such operations would constitute ``minimal processing''
and would not meet the processing definition, as proposed. Thus, under
the proposed rule, coal refuse abandoned in legacy piles would be
considered solid waste, as would the coal refuse that has been
processed and used as a fuel in what was considered to be a minimal set
of sizing activities.
    The proposal also noted one commenter who contended that coal
refuse contained elevated levels of mercury, chromium, and lead when
compared to other coals. Because the proposal already determined coal
refuse in legacy piles to be a solid waste (discarded and
insufficiently processed), we did not believe it was necessary to
determine whether coal refuse from legacy piles would satisfy the
contaminant legitimacy criterion. However, the proposed rule noted that
although coal refuse can contain metals concentrations that are higher
than found in virgin coal, data also show that emissions levels from
some facilities burning coal refuse (namely those equipped with
circulating fluidized beds (CFBs)) are lower than most existing
pulverized coal utility boilers. For the proposed rule's
characterization of coal refuse, see 75 FR 31865-6.
    Accordingly, the Agency seems to have faced a dilemma in deciding
how to treat the ``legacy'' piles. This dilemma was reflected in the
comments, described below, which shows an inherent illogic in treating
coal refuse generated from mining operations today and used as fuel
differently from coal refuse mined from the ``legacy'' piles, which
seem to be no different.
    Comment: Responding to EPA's request for comment regarding whether
other fuels in use today should also be classified as traditional
fuels, several commenters argued that coal refuse should be considered
a traditional fuel, regardless of when generated, as it has been used
as a fuel for approximately 30 years. Citing the preamble to the
proposed rule, commenters stated that EPA recognized that ``changes in
technology and in the energy market over time may result in additional
secondary materials being economically viable to be used as
`traditional' fuels,'' and that the advancement of technology,
specifically the advent of circulating fluidized beds (CFBs), has
allowed coal refuse to be used as fuels for decades.\118\ Thus, these
commenters reason, it is most appropriate to consider coal refuse to be
a traditional fuel.
---------------------------------------------------------------------------

    \118\ Referenced citation can be found at 75 FR 31856.
---------------------------------------------------------------------------

    EPA's Response: We begin by recognizing that we have several
difficulties in dealing with coal refuse. We are faced with a statute
that places limits on the Agency's ability to cover ``discarded''
material. Case law indicates that a material may not lose its waste
status merely because it has value. As technology advances, material
that has been a waste may be no different from material that may today
be used as a product. EPA, in fact, has no jurisdiction to consider as
wastes currently mined coal that was formerly ``refuse.''
    Coal refuse is unique, however, from other non-hazardous secondary
materials addressed in this rulemaking, as it is generated in the
process of producing fuels (i.e., the mining of coal for use as fuel)
and its subsequent use and value as a secondary material is also as a
fuel. Since the primary product of a coal mining operation is itself
fuel, we consider coal refuse to be more akin to a raw material that is
subsequently processed and utilized to produce a fuel. In other words,
coal refuse is different from other non-hazardous secondary materials,
such as used tires or resinated wood residuals, in that it is generated
in the production of fuel and can be used itself as a fuel (and in fact
has never been used for anything else).
    The two materials that are used in major quantities today as
valuable fuels, but have formerly been discarded are coal refuse and
tires. A major difference between these two materials that EPA finds
relevant is that the coal refuse in the legacy piles has never been
used for anything else and is mined as fuel in the first place. Tires,
on the other hand, are originally produced for a use that is
fundamentally different from its current use as a fuel. Cement kiln
users do not ask tire manufacturers to produce tires for burning in the
kilns. Coal, however, was never used for any other activity. It was
mined years ago to produce a fuel, but may now be used itself as fuel.
Therefore, coal refuse is fundamentally different from tires, as well
as the other non-hazardous secondary materials that are discussed in
the preamble to this final rule.
    Responding to commenters that also noted that coal refuse has been
used as a fuel for thirty years due to advances in technology, we find
this information useful, but not determinative in our analysis of
whether or not coal refuse meets our definition of a traditional fuel.
However, the fact that coal refuse has been used and managed as a fuel
for thirty years when coupled with the fact that coal refuse is unique
from other non-hazardous secondary materials in that it is a byproduct
of fuel production processes and is itself a raw material that can be
used as a fuel leads us to determine that coal refuse that is currently
generated and used as a fuel should be considered a traditional
``alternative fuel.'' However, coal refuse that has been abandoned long
ago in legacy coal refuse piles would not be considered a traditional
fuel that is not subject to coverage and assessment in this rule, since
it is clearly a material that has been discarded in the first instance.
    We note that other non-hazardous secondary materials have also been
used as fuels for similar lengths of time or even longer, but would not
be considered traditional fuels. We again emphasize that our decision
to classify coal refuse as an alternative fuel is based both on the
fact that it has been used and managed as a fuel for thirty years
combined with the fact that we find coal refuse to be distinctive among
the other non-hazardous secondary materials at issue in today's rule;
i.e., coal refuse is in fact raw material coal that is generated as a
result of coal

mining operations whose primary product is fuel.
    We also note that our characterization of coal refuse that is
currently generated as an alternative fuel is not inconsistent with the
proposed rule's characterization of this material. The proposed rule
stated that currently generated coal refuse would not be abandoned or
disposed of and, therefore, not a solid waste. The proposed rule did
not, however, specifically state that coal refuse that is currently
generated is a traditional fuel. For clarity, it is appropriate to do
so today, and will amend our definition of traditional fuels to also
include alternative fuels that reflect this determination.
    As previously discussed, coal refuse that has been placed in legacy
piles would not meet the definition of traditional fuels, as they
clearly have not been historically used and managed as a fuel. It is
clear that coal refuse abandoned in legacy piles has been discarded and
managed as a waste. Our rationale for this distinction between coal
refuse that is currently generated and coal refuse that was placed in
legacy piles is further discussed in the comment response below. Thus,
coal refuse that has been placed in legacy piles would be considered
solid waste unless it is processed into a legitimate fuel product. We
respond to comments received regarding the processing of coal refuse
later in this section.
    Comment: Many commenters stated that all coal refuse should be
considered a ``fuel,'' regardless of when the coal refuse is generated
and urged EPA to eliminate the ``false distinction'' based on when the
coal was mined (i.e., coal refuse that is mined from legacy piles
shares the same characteristics as coal refuse that is generated
today).
    At least one commenter cited 40 CFR 60.41 as defining ``fossil
fuel'' as ``natural gas, petroleum, coal, and any form of solid,
liquid, or gaseous fuel derived from such materials for the purpose of
creating useful heat.'' The commenter went on to cite 40 CFR 60.41b,
which states that ``Coal means * * * coal refuse * * *'' \119\ and
argues that this definition in the regulation has nothing to do with
when the coal refuse was generated and should always be considered a
fuel.
---------------------------------------------------------------------------

    \119\ ``Coal means all solid fuels classified as anthracite,
bituminous, sub-bituminous, or lignite by the American Society of
Testing and Materials in ASTM D388 (incorporated by reference, see
Sec. 60.17), coal refuse, and petroleum coke * * *'' See 40 CFR
60.41b.
---------------------------------------------------------------------------

    EPA's Response: We disagree with the comments contending that coal
refuse placed in legacy piles should be characterized and regulated the
same as coal refuse that is generated currently, as this fails to
acknowledge that such coal refuse has been discarded. As has been
discussed, the statutory definition of solid waste turns on whether or
not a material has been discarded in the first instance. Courts have
consistently held that the term ``discard,'' is to have the ordinary,
plain-English meaning (i.e., ``disposed of,'' ``thrown away,'' or
``abandoned''). As coal refuse placed in legacy piles have clearly been
abandoned, we cannot ignore the fact that these materials have been
discarded in the first instance and, therefore, do not agree with the
contention that this construct represents a ``false distinction.'' The
resulting distinction may lead to results that some may find illogical,
but we are faced with the definition of ``discard'' and the fact that
the mere fact that discarded material may have value does not allow the
material to lose its waste status.
    Although we recognize that all coal refuse is (and was) generated
during the fuel production process and are more akin to raw materials,
coal refuse that has been abandoned in legacy piles have not been
historically used and managed as a fuel and therefore cannot be
considered a traditional fuel. Because the technology did not exist
that could effectively make use of the fuel value of these materials at
the time of their generation, they were managed as wastes and abandoned
in legacy piles. While we find that currently generated coal refuse
should now be considered alternative fuels for the reasons stated
above, we cannot ignore that coal refuse that has been placed in legacy
piles have clearly been discarded and, thus, unless these materials are
``sufficiently processed'' and satisfy all legitimacy criteria for
fuels, these secondary materials would be considered solid wastes when
burned as fuels in combustion units.
    Regarding the comments that argue that EPA has previously defined
coal to include coal refuse, we note that this information was helpful,
but disagree the cited regulatory definitions control in this
rulemaking. The cited definitions, which are included in the standards
of performance for new stationary source regulations, were developed
pursuant to the CAA and do not address the issue of discard. Today's
rulemaking is being promulgated under RCRA, which, as mentioned above,
hinges on the whether or not the non-hazardous secondary material at
issue has been discarded. EPA also reemphasizes that the distinction is
not between ``fuel'' and ``waste,'' but between fuel that is a
commodity (not a waste because it has not been discarded) and waste
fuel that has value, but is still a waste.
    In the same CFR sections cited by commenters which define coal as
including coal refuse, we note that coal refuse is defined as meaning
``waste-products of coal mining, cleaning, and coal preparation
operations (e.g., culm, gob, etc.) containing coal, matrix material,
clay, and other organic and inorganic material'' \120\ and ``any
byproduct of coal mining or coal mining operations with an ash content
greater than 50 percent, by weight, and a heating value less than
13,900 kJ/kg (6,000 Btu/lb) on a dry basis.'' \121\ These definitions
highlight the uniqueness of coal refuse and in fact support the
distinction we are making between coal refuse that is currently
generated and coal refuse that has been placed in legacy piles. That
is, it may be appropriate to consider coal refuse to be within the
definition of coal because it may now be used as coal, while at the
same time, it may also be appropriate to consider coal refuse to be a
``waste-product'' or ``byproduct'' of coal mining operations. EPA's
evaluation that coal refuse that is currently generated and used as a
fuel has never been discarded and should be considered an alternative
fuel, while discarded coal refuse should be considered a solid waste,
is consistent with these regulatory definitions.
---------------------------------------------------------------------------

    \120\ See 40 CFR 60.41.
    \121\ See 40 CFR 60.41b.
---------------------------------------------------------------------------

    Comment: Most commenters addressing the issue of processing coal
refuse stated that coal refuse from legacy piles is processed the same
way as is virgin coal; that is, the processing of these materials
includes the use of grizzlies, screens, and blending to improve the
quality, remove metal objects, reduce the ash content, reduce the
sulfur content, and reduce concentrations of various constituents.
These comments maintained that this level of processing should satisfy
EPA's definition of ``processing'' because the processing that occurs
is designed specifically to improve the fuel quality and remove
contaminants in the process (for example, metals that are removed with
ash that is screened out).
    One commenter stated that it is illogical and problematic for EPA
to propose a minimal level of processing that requires additional
activities than are used to prepare virgin materials for use. This
commenter provides the example of a company that recovers coal refuse
from previously discarded piles, screen the refuse to remove large
pieces of slate and rock, conducts a chemical

analysis to identify Btu, ash, and sulfur characteristics, hauls the
coal refuse to its preparation plant where it is cleaned just like
mined coal, and then sold as is or blended with mined coal to meet
contractual orders. This commenter argues that EPA did not provide
adequate justification in the proposed rule for why this process would
be insufficient to turn a once discarded non-hazardous secondary
material into a non-waste fuel product.
    Additionally, commenters noted that in the case of facilities
burning coal refuse, regardless of whether it is generated currently or
was placed in legacy piles, the engineering design of a CFB is based on
the quality of the coal refuse available to be burned in the boiler. In
other words, considerations for use of the coal refuse as a fuel
precede facility construction and directly impact boiler design and
application. Therefore, coal refuse from legacy piles that is processed
in this manner (i.e., in the same manner as currently generated coal
refuse) should not be considered a solid waste.
    EPA's Response: As finalized in Sec.  241.2, the term
``processing'' is defined as meaning ``any operations that transform
discarded non-hazardous secondary material into a non-waste fuel or
non-waste ingredient product. Processing includes, but is not limited
to, operations necessary to: remove or destroy contaminants;
significantly improve the fuel characteristics of the material, e.g.,
sizing or drying the material in combination with other operations;
chemically improve the as-fired energy content; or improve the
ingredient characteristics. Minimal operations that result only in
modifying the size of the material by shredding, do not constitute
processing for purposes of this definition.'' We have determined that
this definition encompasses an appropriate level of processing
necessary to render a discarded material into a non-waste product.
    As several commenters noted, the processes that are employed to
recover coal refuse that has been placed in legacy piles in order to be
used as fuels are the same as the processes that virgin coal is subject
to. As discussed above, coal refuse is unique from other non-hazardous
secondary materials in that it is a byproduct of fuel production
processes and is itself a raw material that can be used as a fuel.
Because coal refuse is essentially raw material coal, which is
generated in the production of fuel and can be used itself as fuel, we
agree with the commenter who stated that it would be illogical to
require a different level of processing for discarded coal refuse than
is used for virgin coal. Therefore, coal refuse that is recovered from
legacy piles and used as fuel that is subjected to the types of
operations that are used to process virgin coal, which serve to both
increase energy values as well as reduce contaminants, would meet our
definition of processing and would not be considered solid waste,
provided these materials satisfy our legitimacy criteria, which they do
since currently mined coal is certainly a legitimate fuel and is the
same as those from the legacy piles.
    Comment: EPA received comments providing new contaminant data for
coal refuse. However, some commenters acknowledged that coal refuse can
have higher levels of some metals, but agreed with EPA that coal refuse
is typically used as a fuel in newer boilers equipped with CFBs, which
have emissions levels lower than most existing coal utility
boilers.\122\ One commenter stated that notwithstanding the higher
metals content of coal refuse, CFBs typically capture between 90-99
percent of mercury and other metals. While most commenters noted that
emissions levels associated with burning coal refuse are similar to
those found when burning virgin coal, one commenter did provide a
comparison in concentration levels of various contaminants between coal
refuse and regional coal samples. A selection of the specific data
provided by the commenter is replicated in Table 5 below:
---------------------------------------------------------------------------

    \122\ CFBs ability to achieve lower emissions levels is due to
several factors: (1) CFB boilers are often newer than many existing
pulverized coal utility boilers and may be equipped with better
particulate matter (PM) controls; (2) CFBs utilize lower operating
temperatures, which result in lower metal and NOX
emissions; and (3) CFB boilers often add limestone to their feed to
control SO2 emissions, which results in greater fixation
to the ash.
    \123\ Coal sample data found in the U.S. Geological Survey--
National Coal Resources Data System. For more information, see
http://energy.er.usgs.gov/coalqual.htm).

                 Table 5--Comparison of Trace Metal Contents (ppm) of Regional Coal Samples and Coal Refuse From Legacy Piles, as Provided in Comments on the NHSM Proposed Rule
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
               Sample description                              Sample ID                 Sb       As       Be       Cd       Cr       Co       Pb       Mn       Hg       Ni       P        Se
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Coal samples from USGS database--Cambria,         No. Samples.......................      244      244      244      244      244      244      244      244      244      244      244      244
 Indiana, and Somerset Counties, PA \123\.
                                                  Minimum...........................     0.11        0      0.6     0.01        2      1.5      0.8        2     0.00      3.4       22     0.68
                                                  Maximum...........................     7.80      200      9.5     1.00       65     34.0     44.0      390     2.90     86.0     3400    20.00
Samples of coal refuse from legacy piles located
 in Cambria, Indiana, and Somerset Counties, PA.
                                                  Sample 1..........................      1.5     50.7      2.1      0.3     80.2     22.7     33.1      134    0.644     44.7      718      7.8
                                                  Sample 2..........................      1.7     53.4      2.1      0.3     84.5     23.8     35.2      139    0.748     50.5      719      8.6
                                                  Sample 3..........................      1.5     47.3      2.1      0.3     84.7     22.8     33.1      144    0.613     47.1      745      8.6
                                                  Average...........................      1.6     50.5      2.1      0.3     83.1     23.1     33.8      139    0.668     47.4      727      8.3
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

    This data indicates that the concentration of the various
contaminants in the coal refuse samples were lower for almost all
constituents (including mercury and lead) when compared to regional
coal samples. According to this data set, only chromium was
consistently higher in the coal refuse samples than the regional virgin
coal, which also indicates that the difference in concentration may be
much closer than previously indicated in the preamble to the
proposal.\124\ Therefore, provided

that coal refuse from legacy piles are sufficiently processed, this
commenter asserts that coal refuse would pass the contaminant
legitimacy criterion and should therefore not be classified as a solid
waste.
---------------------------------------------------------------------------

    \124\ Data provided by the commenter indicated that the average
chromium levels of coal refuse was 83.1 ppm, whereas the range of
chromium levels for the regional virgin coal samples was between 2-
65 ppm. The proposed rule noted that chromium levels of coal refuse
can be up to four times higher than virgin coal.
---------------------------------------------------------------------------

    EPA's Response: Regarding the contaminant levels in coal refuse in
legacy piles, we agree with those commenters who acknowledged that coal
refuse can have higher concentrations of some metals than is found in
virgin coal. As noted in the proposed rule, at least one commenter on
the ANPRM contended that coal refuse could have up to four times more
mercury and chromium, and three times more lead than virgin coal.\125\
We note that this commenter did not provide primary sources for this
data, a point which was raised by at least one commenter. We generally
recognize, however, that available data show that coal refuse placed in
legacy piles often has higher metals concentrations than non-refuse
coal concentrations, but we would presume that the levels of
contaminants are the same as in currently mined coal that would have
been placed into these piles in the past. We also recognize that
contaminant levels will vary significantly depending upon the region
and type of coal at issue.\126\
---------------------------------------------------------------------------

    \125\ See 75 FR 31865.
    \126\ See our Materials Characterization Paper on Coal Refuse,
located in the docket for today's final rule.
---------------------------------------------------------------------------

    As discussed above, we now determine that coal refuse that is
currently generated should be considered an alternative fuel. On the
other hand, coal refuse that is recovered and processed from the
discard environment would need to pass the legitimacy criteria in order
to be considered a non-waste fuel. As coal refuse is recovered from
legacy piles are subject to the same processes as currently-generated
coal refuse in order to meet the same fuel specifications, they would
contain any potential contaminants at levels that are comparable to or
lower than coal refuse that is currently generated.
    We would further note that the contaminant data provided by the one
commenter demonstrates that there are also examples of coal refuse
taken from legacy piles satisfying the contaminant legitimacy criterion
when directly compared to contaminant levels in coal. Given the
regional variations in coal compositions, the analysis is on point
given the fact that the commenter compared similar regional coal refuse
and virgin coal samples. Therefore, we agree with the commenter that
there are instances when coal refuse would also satisfy the contaminant
legitimacy criterion when compared to virgin coal as well.
    Finally, we would note that although emissions comparisons are not
a direct indicator of whether these materials satisfy the contaminant
legitimacy criterion, the emissions from CFBs that use coal refuse as
fuel typically have lower levels of emissions than typical pulverized
coal burners.
    Comment: Several commenters contended that the management of coal
refuse at mining sites is already regulated under the Surface Mining
Control and Reclamation Act of 1997 (SMCRA) and that defining coal
refuse as a solid waste would be inconsistent with SMCRA. Specifically,
some commenters point out that although the term ``solid waste'' under
RCRA includes mining waste in the definition, EPA determined, in
accordance with section 1006(c) of RCRA that provides for the
integration of RCRA with SMCRA, that materials and products associated
with coal mining activities should not be regulated as hazardous
wastes.
    EPA's Response: RCRA section 1006(c) pertains to hazardous wastes
under RCRA subtitle C. As such, it is inapplicable for today's
rulemaking, which is solely concerned with non-hazardous secondary
materials. Thus, we disagree with those commenters who cited section
1006(c) of RCRA and argued that regulation of coal refuse found in
legacy piles should be deferred to SMCRA. In addition, SMCRA is
concerned with the management and removal of coal refuse piles at
mining sites. It does not address the issue of ``discard,'' which is
critical to the definition of solid waste under RCRA, and as such,
which emission standards coal refuse that is in legacy piles and burned
in a combustion unit is subject to under the CAA.
9. Coal Combustion Residuals 127 128
---------------------------------------------------------------------------

    \127\ In a separate rulemaking effort, EPA has proposed
regulations that will provide for the safe disposal and management
of coal combustion residuals from utility coal-fired power plants
(the ``Coal Combustion Residuals Proposed Rule''). The proposed rule
was published in the Federal Register on June 21, 2010. See 75 FR
35127. Today's final rule does not affect that rulemaking effort, as
our rule considers the use of coal combustion residuals in
combustion units as fuels or ingredients, while the coal combustion
residual proposed rule is concerned with the safe disposal and
management of these residuals in landfills and surface impoundments.
For more information on the coal combustion residual proposed rule,
see Docket ID No. EPA-HQ-RCRA-2009-0640.
    \128\ For a discussion of CCRs used as ingredients, see Section
V.C.2 of this final rule.
---------------------------------------------------------------------------

    Coal combustion residuals (CCRs) are formed during coal-burning
processes in power plants and industrial boilers, and are produced in
various forms that are categorized by the process in which they are
generated. The proposed rule differentiated between CCRs (which include
such secondary materials as fly ash, bottom ash, and boiler slag), that
are currently generated from those CCRs that have been previously
disposed of (such as, mined landfill ash) and are used as fuels in
combustion units. Under the proposed rule, currently generated CCRs
that have not been discarded in the first instance and satisfy the
legitimacy criteria would not be considered a solid waste when used as
a fuel in combustion units provided the CCRs were burned in units
within the control of the generator. For example, the proposal
described a situation where currently generated, high-carbon fly and
bottom ash that is taken directly from existing boilers is burned
within the control of the generator at power generating stations. On
the other hand, CCRs recovered from landfills or other disposal units
would clearly have been discarded in the first instance and would
therefore have to be sufficiently processed into a non-waste fuel
product and meet the legitimacy criteria in order not to be considered
a solid waste when used as a fuel.
    The proposed rule also noted comments received on the ANPRM
describing patented processes that separate the carbon from the fly ash
in order to produce a new fuel product. Although this level of
processing appeared likely to meet the proposed definition of
processing, the proposed rule solicited comment on how CCRs are
processed. The proposed rule also requested comment regarding the
extent to which CCRs are recovered from the discard environment (e.g.,
landfills) and used as fuels. For the proposed rule's discussion of
CCRs used as fuels, see 75 FR 31865-6.
    Comment: Most commenters argued that CCRs, when used in combustion
units, should be classified as ingredients rather than as fuels. The
commenters often contended that classifying all CCRs as ingredients
would simplify waste determinations for these secondary materials by
clearly establishing the appropriate legitimacy criteria that apply
(i.e., facilities would not need to determine whether the fuel or
ingredient legitimacy criteria apply based on the primary purpose of
the secondary materials). Some commenters acknowledged, however, that
CCRs can be combusted (e.g., by electric utilities) for energy recovery
of its carbon content

or combustion in carbon burn-out (CBO) units for processing marketable
fly ash products.
    One commenter described CBO units, which they explained burn
``unwanted carbon'' from fly ash to produce a low-carbon fly ash that
is more suitable for use as an ingredient in Portland cement, as being
typically integrated with power plants. The CBO unit combusts fly ash
from the power plant in a fluidized bed, extracts the residual energy
content of the fly ash to fuel the CBO, and returns useful heat to the
power plant. The commenter stated that the major equipment that
comprises the CBO unit includes a fluidized bed combustor and heat
exchanger to recover heat from the fly ash combustion. This same
commenter described the heat generated from the combustion of the
carbon in the fly ash as ``valuable'' and is typically recovered from
the CBO and used to heat the host plant's condensate stream, which
reduces the amount of extraction steam required. In reasoning that this
high-carbon fly ash should be considered an ingredient, however, the
commenter notes that energy generated from burning the secondary
material is of secondary importance to the production of the valuable
low-carbon fly ash to be sold to cement kilns.
    EPA's Response: We do not agree with commenters that all CCRs, when
used in combustion units, should categorically be defined as
ingredients. As some commenters acknowledged, some CCRs are indeed used
for their fuel value as opposed to their ingredient value, especially
when re-burned, as in the case of their use in combustion units by
electric utilities. Therefore, we cannot categorically classify CCRs as
ingredients when it is clear that, in some cases, these secondary
materials are being burned for their fuel value and/or to produce a new
secondary material (i.e., low-carbon fly ash). In cases where the
primary purpose of using CCRs is for their fuel value and not for the
ingredient value (e.g., by electric utilities in utility boilers), the
secondary materials must meet the requirements for fuels, including the
legitimacy criteria, in order to not be considered a solid waste. In
other words, to the extent that CCRs are used as fuels, these secondary
materials must remain within the control of the generator and meet the
legitimacy criteria for fuels or be sufficiently processed into a new
fuel product in order not to be considered a solid waste. We note,
however, that sources may petition the Agency for a non-waste
determination for secondary materials managed outside the control of
the generator, including CCRs. See Section VII.G.
    Regarding CBO units that burn high-carbon fly ash, creating both
energy, as well as a new marketable ingredient (i.e., low carbon fly
ash), this activity would not constitute use of these secondary
materials as ingredients. When the fly ash goes into a CBO unit, it is
clearly not being used as an ingredient, but is used to produce an
ingredient. It is less clear, however, whether this activity represents
a legitimate use of these secondary materials as fuels or should be
considered a type of waste management. The commenter states that
burning of this fly ash in CBO units provides ``valuable heat'' and
indicates that the energy is used in turn to power the CBO or returned
to the power plant, which indicates that the burning of the fly ash
could constitute a legitimate use as a fuel. On the other hand, the
same commenter also noted that the fuel value is ``secondary'' to its
value as an ingredient and the CBO process as removing ``unwanted
carbon'' from the fly ash, which may suggest that the fly ash is being
burned as a waste activity (i.e., the destruction of the unwanted
carbon in order to generate a marketable product).
    Unfortunately, from the comments received, we are not able to make
a categorical determination whether or not the burning of fly ash in
these units would constitute ``discard,'' as it is unclear whether the
carbon is being destroyed or whether it is actually used for its fuel
value. In other words, the CBO unit is either ``destroying'' the
carbon, which would make these materials a solid waste, or the carbon
is being recovered and used as a fuel, in which case these materials
would not be considered a solid waste provided they meet the legitimacy
criteria.
    While the CBO units are burning the ash to create a marketable
product, in so doing they may also be utilizing the separated carbon
for its fuel value. The commenter indicates that use of high carbon-fly
ash in these CBOs may have more than marginal energy value and can even
be a source of additional power to an adjoining power plant. While we
do not have sufficient information to make a categorical determination
regarding the use of fly ash as a fuel in these CBO units, it is
appropriate for these units to consider the legitimacy criteria in
order to determine whether or not the fly ash is being burned for
discard or burned legitimately for its fuel value.
    As discussed in Section VII.H, legitimacy criteria are critical to
ensuring that non-hazardous secondary materials are being legitimately
used. To the extent that a CBO unit can determine that it meets the
legitimacy criteria for fuels (including whether the fly ash has
meaningful heating value and is used as a fuel in a combustion unit
that recovers energy), we would consider such a use to be legitimate.
We emphasize, however, that mere destruction of the unwanted carbon
would clearly represent discard and would by definition fail the
meaningful heating value legitimacy criterion. We also note that it is
not clear from the comments how the CBO unit recovers energy and
whether it would meet our definition of a legitimate energy recovery
device. For a discussion of legitimate energy recovery devices, see the
Response to Comments on Sewage Sludge (Section V.B.10). If these units
do not legitimately recover energy, they would not meet the meaningful
heating value criterion. See also Section VII.I, which discusses the
types of notification and recordkeeping requirements, including
documentation as to how the non-hazardous secondary material meets the
legitimacy criteria, that a facility using these secondary materials as
fuels that remain within the control of the generator are subject to.
    Finally, we note that the resulting low-carbon fly ash would be
considered a new secondary material, which would be considered an
ingredient if it is later used in the production of cement.
    Comment: One commenter, a utility, stated that the proposed rule's
setting of minimum energy content values for a secondary material to be
used as a fuel and not be considered a solid waste (i.e., the
meaningful heating value legitimacy criterion) is inappropriate for the
re-burning of fly ash when producing concrete quality fly ash, as the
coal ash used for re-burn is selected based on its mineral content,
combined with the mineralogy of the coal currently being used as a
fuel. The fuel value of the fly ash is only one technical consideration
when introducing coal ash in combustion systems for creating concrete
quality fly ash and requiring a minimum heating value may restrict the
use of high quality fly ash for use in concrete and other applications.
    EPA's Response: We appreciate that the fuel value is only one of
several considerations made when selecting fly ash for re-burn;
however, in order for fly ash that is re-burned to not be a solid waste
under today's final rule, it would need to either remain within the
control of the generator and meet the legitimacy criteria for fuels,
including the meaningful heating value criterion, or, if discarded, be
processed into a new, legitimate fuel product. Some

commenters stated that the energy content of fly ash when burned is
returned as useful heat. Based on the comments received, however, it is
unclear whether the fly ash in that instance would meet the meaningful
heating value criterion, as these comments do not include enough
information about how much energy is being recovered from the use of
these secondary materials as fuels. In order to not be considered a
solid waste, the facility must determine whether the fly ash meets the
legitimacy criteria, including whether the fly ash has meaningful
heating value and is used as a fuel in a combustion unit that recovers
energy.
    We also note that we are not establishing a bright line test for
satisfying the meaningful heating value test. Rather, for purposes of
meeting the legitimacy criteria for fuels, we would consider non-
hazardous secondary materials with an energy value greater than 5,000
Btu/lb, as-fired, to have a meaningful heating value, and satisfy this
legitimacy criterion. However, for facilities with energy recovery
units that use non-hazardous secondary materials as fuels with an
energy content lower than 5,000 Btu/lb, as fired, we believe it is also
appropriate to allow a person to demonstrate that a meaningful heating
value is derived from the non-hazardous secondary material if the
energy recovery unit can cost-effectively recover meaningful energy
from the non-hazardous secondary materials used as fuels. See Section
VII.H.1 for a discussion of how non-hazardous secondary materials can
satisfy the meaningful heating value criterion for fuels.
    Comment: Some commenters argued generally that EPA should not
restrict the source of coal ash that is re-burned and should allow coal
ash that is used as a fuel to be transferred between facilities and
retrieved from landfills because it is being beneficially used. One of
these commenters described how one of its power plants re-burns coal
ash that it receives from two other power plants that it also owns.
This same commenter also noted that it re-burns coal ash in one of its
power plants that it has retrieved from an off-site landfill.
    EPA's Response: As discussed in Section V.A.1, EPA is not making a
sweeping arbitrary assumption in categorizing transferred secondary
materials as discarded. Instead, EPA has evaluated whether certain
categories of materials are discarded or not. The Agency has not
adopted the extremes of saying that all burning of secondary material,
regardless of ultimate use, is waste treatment or that any secondary
material that is recycled for legitimate fuel value is a commodity and
not a waste. Wastes may have value, but are still wastes.
    Between these broad parameters, EPA has examined a number of
specific materials, recycled on-site and transferred for recycling, and
determined whether they would be appropriately placed within the waste
or non-waste categories. EPA would consider transferred non-hazardous
secondary materials not to be wastes if it could make the appropriate
findings for those categories. In fact, the Agency does so with respect
to scrap tires harvested from vehicles and resinated wood residuals.
    Commenters discussing scrap tires and resinated wood residuals,
however, provided specific information regarding how these secondary
materials were managed when they no longer remained within the control
of the generator and the frequency with which these materials were
collected and transferred off-site. For example, resinated wood
residuals are routinely transferred between either intra- or inter-
company facilities and used as either ``furnish'' (i.e., raw materials)
or fuel at the receiving facilities. The material being transferred
off-site is used and handled in the same manner that resinated wood
residuals are used when generated on-site (such that it is impossible
to distinguish between materials that are being used as a raw material
and those that are being used as a fuel).
    On the other hand, commenters discussing the use of CCRs as fuels
outside the control of the generator did so only in general terms.
Commenters provided legal arguments that case law holds that transfer
of such materials between companies were irrelevant for determining
whether a recycled material was properly viewed as a solid waste. See
Section V.A.1 for our response to these legal arguments on the issue of
``transfer'' as it relates to the concept of discard. However, these
commenters did not specify how the proposed rule's presumption that
non-hazardous secondary materials that are used as fuels and are
managed outside the control of the generator are solid wastes was
inappropriate for CCRs. In general, the DC Circuit has not accepted
such presentations in ``broad abstraction.'' See ABR at 1056.
    Because commenters did not provide sufficient information detailing
how CCRs are managed when transferred outside the control of the
generator, we are unable to determine whether such movement of CCRs
outside the control of the generator is or is not indicative of
discard. Thus, such a determination is best left to the non-waste
petition process, as finalized in today's rule. As we've discussed, we
believe this petition process is essential because many non-hazardous
secondary materials are recycled and managed in many different ways,
and the Agency may lack the specific details in certain cases to know
whether such non-hazardous secondary materials are or are not solid
wastes. For a discussion of non-waste determination petitions, see
Section VII.G of today's rule.
    Regarding the commenter who described how one of its power plants
re-burns coal ash that it receives from two other power plants it also
owns, we would expect that such a situation would fall within the
definition of ``within the control of the generator,'' as codified in
Sec.  241.2. For the purposes of today's final rule, ``within the
control of the generator'' means that the non-hazardous secondary
material is generated and burned in combustion units at the generating
facility; or that such material is generated and burned in combustion
units at different facilities, provided the facility combusting the
non-hazardous secondary material is controlled by the generator; or
both the generating facility and the facility combusting the non-
hazardous secondary material are under the control of the same person.
We have also codified the definition of ``control'' as meaning the
power to direct the policies of the facility, whether by the ownership
of stock, voting rights, or otherwise, except that contractors who
operate facilities on behalf of a different person as defined in this
section shall not be deemed to ``control'' such facilities. See Sec.
241.2. As the commenter states that it owns the other two plants, such
intra-company movement would ensure that the materials would remain
within the control of the generator and, therefore, such CCRs would not
be considered a solid waste when used as a fuel provided they meet the
legitimacy criteria. In the instance where a facility is re-burning
coal ash that is recovered from landfills, such coal ash is a solid
waste, as this material has clearly been discarded. Coal ash that is
recovered from landfills must be sufficiently processed in order to no
longer be considered a solid waste.
    Comment: We received a few comments regarding the extent to which
CCRs are mined from landfills (i.e., recovered from the discard
environment). One commenter asserted that it was unaware of any
recovery of CCR from disposal sites, while one another commenter
acknowledged that while it could utilize recovered landfill fly ash, it
was not currently doing so.

Still another commenter stated it removes CCRs from landfills and that
such removal for either energy recovery or beneficial reuse was
facilitated by a regulatory innovation program sponsored by the state
and endorsed by EPA. Consequently, this commenter commonly re-burns
coal ash that is recovered from landfills. This commenter notes that it
has developed and uses patented processes to use this fly ash, but does
not provide specific details regarding how these secondary materials
are processed.
    EPA's Response: It does not appear that it is a widespread practice
for CCRs to be recovered from the discard environment (e.g., landfills)
and beneficially used. However, from comments received both on the
ANPRM and the proposed rule, it appears that at least some CCRs are
being recovered from the discard environment or could be recovered from
the discard environment--for example by the one commenter citing its
participation in a state regulatory innovation program. Although we
recognize the benefits associated with recovering CCRs from landfills,
these non-hazardous secondary materials have clearly been discarded in
the first instance and would have to be sufficiently processed into a
new fuel product (or ingredient product) to not be considered a solid
waste when used in combustion units. As we've stated elsewhere in the
preamble, today's final rule is limited to CCRs used as fuels or
ingredients in combustion units. In other words, today's rulemaking
should not impact other potential beneficial uses of CCRs, such as
using these secondary materials as a base material to replace stone or
gravel under roads, parking lots and buildings.
    Comment: EPA received comments on the ANPRM stating that there are
at least four patented processes for removing unwanted carbon from fly
and bottom ash that allow the processed ash to produce both technically
compliant ash for use in concrete and a separate carbon stream that can
be re-introduced into the boiler for its fuel value. One electric
utility, commenting on the proposed rule, also mentioned patented
processes for using CCRs recovered from landfills. However, neither of
these commenters provided specific details regarding how the CCRs are
actually processed.
    EPA's Response: Unfortunately, EPA did not receive sufficient
information during the comment period describing the types of processes
that CCRs undergo to be able to make a categorical determination
whether the patented processes referenced in the proposed rule would
meet the definition of processing being promulgated in today's final
rule. Although we did receive some information regarding how CCRs are
processed, we have determined, as we stated in the proposed rule, that
certain operations are currently being utilized to recover CCRs from
the discard environment that would likely meet our definition of
``processing.'' For example, we are aware of at least one electric
utility that recovers ash from ponds or landfills and then separates
this secondary material into its fundamental components: carbon,
silicates, and high-density, iron-rich materials. A coarse carbon-fuel
product is then recovered by density separation using concentrating
spirals. A fine carbon-fuel product is also recovered with flotation
cells.\129\ We believe that this type of processing operation is likely
to meet our definition of processing, as it appears that these
operations in fact remove contaminants and improve the fuel
characteristics of recovered CCRs. Thus, a determination would need to
be made as to whether such processes meet the definition of processing,
as codified in Sec.  241.2.\130\
---------------------------------------------------------------------------

    \129\ See ``Materials Characterization Paper on Coal Combustion
Residuals-Coal Fly Ash, Bottom Ash, and Boiler Slag.'' A copy of
this document has been placed in the docket for today's rule.
    \130\ We note, however, that burning any secondary material,
including CCRs, in a combustion unit would not constitute
``processing,'' as determining whether or not a material is a solid
waste must occur prior to its placement in the combustion unit. To
consider the burning of such materials as ``processing'' would be
circular.
---------------------------------------------------------------------------

10. Sewage Sludge
    The proposed rule classified sewage sludge (or wastewater treatment
sludge) generated from publicly owned treatment works (POTWs) as solid
waste when burned as fuels in combustion units. However, the proposed
rule also specifically solicited comment on whether it is within the
Agency's discretion to provide a regulatory solid waste exclusion for
sewage sludge when burned in incinerators in order to preserve the
current framework for regulating sewage sludge managed under section
405 of the Clean Water Act (CWA) and to avoid redundancy. When making
the determination that sewage sludge is a solid waste when burned as a
fuel in a combustion unit, the proposed rule stated that the Domestic
Sewage Exclusion (DSE) under RCRA (see 261.4(a)) does not apply to the
sludge generated from the treatment process and thus, sewage sludge is
a solid waste if discarded. The proposed rule also noted that burning
sewage sludge without energy recovery (i.e., burned for destruction)
would constitute discard. Responding to commenters describing POTWs
that recover heat in the form of usable heat via waste heat boilers,
the proposed rule stated that the Agency does not consider waste heat
boilers to be legitimate energy recovery devices, but rather these
combustion units are burning the sewage sludge primarily for disposal
purposes. Finally, the proposed rule stated that sewage sludge would
likely not satisfy the contaminant legitimacy criterion, as data
indicates that sewage sludge often contains metals at levels that are
significantly higher in concentration when compared to traditional
fuels. For the proposed rule's discussion of sewage sludge, see 75 FR
31866-7.
    Comment: Several commenters argued that EPA has the discretion to
exclude or exempt sewage sludge from this rulemaking and should
exercise that discretion in order to preserve the current framework for
regulating the burning of sewage sludge pursuant to 40 CFR 503 (Part
503), which codifies regulations developed under the authority of
section 405 of the CWA. These commenters also note that EPA has a non-
discretionary duty to consider all environmental laws to prevent
duplication when promulgating regulations under section 1006(b) of RCRA
and that deeming sewage sludge a solid waste to be regulated under
section 129 of the CAA violates EPA's non-discretionary duty to
harmonize environmental laws because emissions from sewage sludge
incinerators (SSIs) are already comprehensively regulated under other
statutes.
    EPA's Response: We agree with the commenters that section 1006(b)
requires EPA to integrate the RCRA requirements with the requirements
of the CWA and the CAA, as well as other laws. Section 1006(b) also
states that such integration shall be effected only to the extent that
it can be done in a manner consistent with the goals and policies
expressed in RCRA and in the other acts referred to in section 1006(b).
Thus, while we recognize that emissions from SSIs have been regulated
under other statutes, the purpose of today's final rule is not to
regulate emissions from SSIs, but rather to determine whether sewage
sludge is or is not a solid waste to allow the Agency to decide whether
the material must be combusted under emissions standards developed
under section 112 or 129 of the CAA. Sewage sludge is one of many non-
hazardous secondary materials that are discussed and analyzed in this
final rule.
    We also note that section 405(d)(5) of the CWA states that nothing
in section

405 is intended to waive more stringent requirements established by the
CWA or by any other law. This provision clearly states that section 405
of the CWA does not preempt other regulation. Therefore, we believe
today's final rule is consistent with the goals and policies of RCRA,
the CWA, and the CAA and thus, satisfies the requirements of section
1006(b).
    Comment: Commenters asserted that Congress wrote section 112 of the
CAA to regulate sewage sludge emissions, stating that section 112(e)(5)
\131\ of the CAA directs EPA to issue emissions standards under section
112(d) for POTWs, including SSIs. These commenters also argued that
sewage sludge quality and incineration is strictly regulated under the
CWA and that the current regulatory structure under both the CWA and
section 112 of the CAA is effective and should not be altered.
---------------------------------------------------------------------------

    \131\ CAA section 112(e)(5) states, ``The Administrator shall
promulgate standards pursuant to subsection (d) of this section
applicable to publicly owned treatments works (as defined in Title
II of the Federal Water Pollution Control Act [33 U.S.C.A. Sec.
1281 et seq.] not later than 5 years after November 15, 1990.''
---------------------------------------------------------------------------

    EPA's Response: Today's final action is defining solid waste under
RCRA and as such we are not addressing the definition of POTW under the
CWA or the requirements of the CAA.
    Comment: Several commenters reiterated the position that the DSE
applies to sewage sludge generated by POTWs and, therefore, stated that
sewage sludge is exempted from the definition of solid waste under
RCRA. Citing the preamble to the 1980 RCRA subtitle C regulations, at
least one commenter stated that the Agency indicated that once the to-
be-developed regulation under section 405 of the CWA is promulgated,
sewage sludge would be exempt from coverage under other sets of
regulations.\132\ The same commenter also cites the 1990 Petroleum
Refinery Primary and Secondary Oil/Water/Solids Separation Sludge
Listings Rule (1990 Listings Rule), which states ``It should be noted
that if wastewaters generated at petroleum refineries are discharged to
a POTW and such wastewaters are mixed with domestic sewage from
nonindustrial sources, the sludges generated in the POTW are covered
under the domestic sewage exclusion and are not included in today's
listings.'' \133\
---------------------------------------------------------------------------

    \132\ See 45 FR 33102 (May 19, 1980).
    \133\ See 55 FR 46364 (November 2, 1990) (Footnote 14).
---------------------------------------------------------------------------

    EPA's Response: For the same reasons stated in the proposed rule,
we do not agree with the comments suggesting that the DSE applies to
the sludge generated from the treatment process. EPA has long viewed
sewage sludge generated from POTWs as a solid waste, beginning with the
1980 Identification and Listing of Hazardous Waste rulemaking. In that
final rule, EPA stated that the DSE is ``only applicable to non-
domestic wastes that mix with sanitary waste in a sewer system leading
to a POTW.'' \134\ In that same rule, EPA further said it decided not
to exclude sewage sludge from regulation under RCRA, since the
statutory expressions regarding the definitions of ``solid waste'' and
``sludge'' was clear.\135\
---------------------------------------------------------------------------

    \134\ Id at 45 FR 33097.
    \135\ Id at 45 FR 33101. ``Under Section 1004(27) of RCRA, the
definition of ``solid waste'' specifically includes ``sludge from a
waste treatment plant.'' In defining ``sludge,'' Section 1004(26A)
includes wastes from a ``municipal wastewater treatment plan.''
Because of these very clear statutory expressions, EPA must regulate
sewage sludge under RCRA. * * *''
---------------------------------------------------------------------------

    We agree that the 1980 Identification and Listing of Hazardous
Waste rulemaking referenced by the commenter states that once the
regulations are promulgated under section 405(d) of the CWA, sewage
sludge will be exempted from coverage from ``other sets of
regulations.'' The preamble continues, however, to state: ``In
particular sewage sludge that qualifies as a hazardous waste will be
exempted from this Part [261] and Parts 262 through 265'' once this
program is promulgated under CWA section 405. However, this exclusion
is specifically limited to RCRA subtitle C (i.e., hazardous
waste),\136\ and does not apply to the subtitle D program under RCRA.
---------------------------------------------------------------------------

    \136\ We would note that even though the CWA section 405(d)
regulations have been promulgated, EPA never exempted sewage sludge
from the subtitle C hazardous waste regulations, and thus, sewage
sludge that exhibits any of the characteristics of hazardous waste
must be managed as a hazardous waste. See 45 FR 33102, May 19, 1980
where it states, ``The Agency's strategy for the development of a
comprehensive sewage sludge management regulation will eventually
result in the establishment of a separate regulation. Once such a
regulation is in place, sewage sludge will be exempted from coverage
under other sets of regulations. * * * Pending promulgation of this
comprehensive sewage sludge regulation, sewage sludge will not be
specifically excluded from Subtitle C.''
---------------------------------------------------------------------------

    Regarding the citation from the 1990 Listings Rule, this footnote
is in error and is inconsistent with our historic interpretation of the
scope of the DSE, as discussed both in the proposed rule and today's
final rule. Thus, the DSE does not apply to the sludge generated from
the treatment process.
    Comment: Several commenters stated that sewage sludge has
meaningful heating value and that EPA should re-evaluate its
description of this criterion. Commenters argued that EPA's
determination that waste heat boilers do not qualify as combustion
units that recover energy is arbitrary and does not recognize the
significant value of waste heat boilers and their role in energy
generation. One commenter, a regional sewer district that estimated
roughly 93 percent of its sewage sludge was ``incinerated,'' stated
that four of its boilers had produced a total of 2.5 billion pounds of
high pressure steam over a twenty-five year span by converting the heat
generated from burning sewage sludge in multiple hearth incinerators to
high pressure steam.
    EPA Response: We find that most sewage sludge is burned not for
energy recovery, but for destruction. Sewage sludge burned in an
incinerator for the purposes of destruction would clearly meet the
meaning of discard, and thus be a solid waste. While we recognize that
waste heat boilers are useful devices for providing energy in the form
of steam for secondary processes, the presence of a waste heat boiler
does not, by itself, change the fact that the unit combusting the non-
hazardous secondary material is primarily an incineration unit burning
waste for disposal purposes.
    Further, the Agency does not regard waste heat boilers as
legitimate energy recovery devices because they receive their energy
input from the combustion of off-gases via a separate combustion
chamber. Under the RCRA program, a legitimate energy recovery device is
one that meets the definition of a boiler or an industrial
furnace.\137\ Among other criteria, a boiler's combustion chamber and
primary energy recovery section(s) must be of integral design, unless
it falls under the process heater or fluidized bed combustion
exemption. Thus, a combustion chamber that is connected by a duct to a
waste heat boiler (or recuperator/heat exchanger) does not qualify as a
legitimate energy recovery device.
---------------------------------------------------------------------------

    \137\ See February 28, 1984 Memorandum from John H. Skinner,
Director, Office of Solid Waste, to Thomas W. Devine, Director, Air
and Waste Management Division, EPA Region IV, entitled, ``Guidance
on Determining When a Hazardous Waste Is a Legitimate Fuel That May
Be Burned for Energy Recovery in Boiler or Industrial Furnace.'' A
copy of this memorandum is included in the docket for today's rule.
For definitions of ``boiler'' and ``industrial furnace'' under RCRA,
see 40 CFR 260.10.
---------------------------------------------------------------------------

    Unlike boilers, which are specifically designed to recover the
maximum amount of heat from a material's combustion, waste heat
recovery units are designed to cool the exhaust gas stream, and/or to
recover, indirectly, the useful heat remaining in the exhaust gas

from a combustion unit that has some other primary purpose (such as an
institutional waste incinerator). Thus, we continue to consider that
sewage sludge is primarily burned for destruction and the presence of a
waste heat recovery unit would not, by itself, satisfy the meaningful
heating value legitimacy criterion.
    Comment: Regarding the contaminant levels in sewage sludge, a
number of commenters noted that the pretreatment standards have reduced
contaminants (particularly metals) in sewage sludge, with a few
commenters providing more recent contaminant data for sewage sludge
than was available in the proposed rule and stated that this new data
demonstrates that currently generated sewage sludge would meet the
contaminant legitimacy criterion.\138\ The National Association of
Clean Water Agencies (NACWA) amended the data set included in the
proposed rule by providing data from a 2006-2007 Targeted National
Sewage Sludge Survey (TNSSS). See column four of Table 6 below:
---------------------------------------------------------------------------

    \138\ The proposed rule included a table comparing sewage sludge
data taken from a 1982 40-city study and a 1988 National Sewage
Sludge Survey, cited in the National Biosolids Partnership's 2005
``National Manual of Good Practices for Biosolids,'' and coal data
taken from a 1998 U.S. EPA report entitled, ``Development of
Comparable Fuels Specifications.'' May 1998.

          Table 6--Comparison of Toxics of Municipal Wastewater Treatment Sludges to Traditional Fuels
----------------------------------------------------------------------------------------------------------------
                                                                                Targeted
                                                                     National        national
                     Element                       40 City study   sewage sludge   sewage sludge       Coal
                                                      (1982)      survey  (1988)      survey
                                                                                (TNSSS)
----------------------------------------------------------------------------------------------------------------
                                                    Mg/dry kg
----------------------------------------------------------------------------------------------------------------
Arsenic.........................................             9.9             6.7             6.9              10
Cadmium.........................................              69             6.9             2.6             0.5
Chromium........................................             429             119              80              20
Lead............................................             369           134.4              76              40
Mercury.........................................             2.8             5.2             1.2             0.1
Nickel..........................................           135.1            42.7              48              20
Selenium........................................             7.3             5.2               7               1
----------------------------------------------------------------------------------------------------------------

    Other commenters, however, agreeing that sewage sludge should be
considered a solid waste, noted that sewage sludge tended to have
higher contaminant levels than traditional fuels and should be
regulated as solid waste when used as a fuel. Although not a part of
the proposed definition of ``contaminants,'' some commenters noted the
presence of pathogens in sewage sludge.
    EPA's Response: The Agency appreciates the more recent and site-
specific data provided by several commenters. We agree that in most
cases, the specific data provided by commenters indicates that
contaminant levels for most contaminants is not as high as previously
reported in the earlier studies. However, we note that the TNSSS data
provided by commenters still indicates higher levels, and those that
EPA would not consider to be ``comparable'' for most of the
contaminants found in sewage sludge when compared to coal. Thus, under
today's final rule, sewage sludge would not satisfy the contaminant
legitimacy criterion because of the presence of non-comparable levels
of metals when compared to traditional fuels. Regarding the commenter's
reference to pathogens, pathogens are not included as a contaminant in
today's rule since that definition focuses on those constituents
identified in the CAA that EPA will be evaluating to determine whether
to establish emission standards (see also discussion in V.D.3).
    Comment: Finally, several commenters urged EPA to explicitly limit
the scope of the final rule, making it clear that this rulemaking would
have no regulatory effects or impacts for sewage sludge that is not
incinerated (e.g., land application). On the other hand, one commenter
requested that the Agency designate sewage sludge as a solid waste
regardless of the manner that it is managed for disposal (land
application, surface disposal, co-disposal in a municipal solid waste
landfill, or incineration).
    EPA's Response: We disagree with the one commenter who requested
that this rulemaking define sewage sludge as a solid waste regardless
of its end use (i.e., land application, surface disposal, etc.). In
this final rule, EPA is articulating a framework for determining
whether a non-hazardous secondary material is or is not a solid waste
when burned as a fuel or ingredient in a combustion unit; we are not
making solid waste determinations that cover other possible end uses
(e.g., land application of sewage sludge). It is the Agency's view that
these regulations should not dictate to state programs how to
characterize and/or regulate this material (as well as any other non-
hazardous secondary material), particularly since EPA does not have
authority to regulate the beneficial use of non-hazardous secondary
materials under subtitle D of RCRA. Therefore, EPA agrees with those
commenters who suggested the limited scope of this final rule and
explicitly recognize the narrow focus of this rulemaking.
11. Processed Fats
    Processed fats, including both animal fats and vegetable oils, can
be turned into biofuels for use in industrial boilers. The proposal did
not discuss the use of this non-hazardous secondary material or discuss
its status as a fuel or waste under this rule. We did receive comments
pertaining to its status, however.
    Comment: Commenters have argued that processed fats are a
traditional fuel as they are not discarded and are legitimate fuel
products. Specifically, they argue that the use of processed fats as
fuel has been used in industrial boilers for more than a decade, as
evidenced by approval of the use of such fats as fuels in air permits
for industrial boilers. The commenters also note that processed fats
are a primary product of the rendering process and not secondary
materials or by-products, are derived from inedible animal products,
which are the primary products of value and sale of the meat industry
and not a secondary material or by-products, and are therefore not a
solid waste since it or its primary feedstock have never been a waste
or discarded.

    Processed fats also are managed as valuable commodities and have
meaningful heating value. They are managed similar to traditional oils,
utilizing the same tanks, hoses, nozzles, and tanker trucks, and have a
heating value of around 17,000 Btu/lb.\139\ Processed fats, the
commenters argue, also have a comparable composition to traditional
fuel products. In fact, processed fats contain considerably less
contaminants (e.g., <0.010% sulfur by weight, 0.022% ash by weight) and
burn cleaner than many traditional fuels and derivatives (e.g., coal,
oil, coal tar oil, asphalts, etc). The limited contaminant data that
was submitted showed that processed fats had less than 1 ppm of
vanadium. Commenters also stated that processed fats have fewer
contaminants than No. 6 residual oil (2% sulfur content), which will
result in lower emissions of sulfur dioxide, nitrogen oxides,
particulate matter, and carbon monoxide. Furthermore, they stated that
processed fats also have lower emissions of sulfur dioxide, particulate
matter and carbon monoxide, as compared to No. 2 distillate oil (0.5%
sulfur content). However, no data was submitted to validate these
statements.
---------------------------------------------------------------------------

    \139\ See document EPA-HQ-RCRA-2008-0329-0706.1. Adams, T.T., J.
Walsh, M. Brown, J. Goodrum, J. Sellers, and K. Das, 2002. ``A
Demonstration of Fat and Grease as an Industrial Boiler Fuel,''
University of Georgia, Athens, GA.
---------------------------------------------------------------------------

    The commenters also note that the federal government has encouraged
the development and use of materials, such as processed fats as a
clean, renewable fuel that reduces dependency on petroleum oils. Since
2006, the use of processed fats as fuel has been encouraged through the
Alternative Fuel Mixture Credit (26 U.S.C. 6426(e)). Although the
proposed rule is intended to facilitate the use of certain materials
that would otherwise be treated as waste by allowing them to be
designated as non-hazardous secondary materials and burned as fuels,
the net effect, with respect to processed fats, is the opposite. Rather
than facilitate the use of processed fats as fuel, the rule will
effectively end the development of this market. This is because the end
result under the rule as it currently is proposed is a requirement that
each potential customer must petition and obtain EPA approval for each
facility in which they wish to burn processed fats. The burden and
delay of submitting to such a process will have a chilling effect on
the development of new customers and markets for processed fats as
fuel. As a practical matter, this outcome is contrary to longstanding
federal policy encouraging the development and use of clean, renewable
fuels in place of petroleum and other fossil fuels.
    EPA's Response: We disagree that process fats are a traditional
fuel. Process fats are secondary materials as they are produced from
inedible parts of animals that were primarily butchered for meat, not
for use as a fuel. We recognize, however, that these non-hazardous
secondary materials contain lower concentrations of contaminants than
traditional fuels \140\ and, as such, are being encouraged for use
instead of fossil fuels.\141\ In addition, since the fats are managed
the same way that traditional oil is, it is evident that the material
is handled as a valuable commodity, meeting that legitimacy criterion.
Additionally, the material meets the legitimacy criterion for a
meaningful heating value. Since these materials are sometimes not
managed within the control of the generator (i.e., the butcher, the
restaurant, etc.), questions could be raised as to whether they are
discarded if not burned in a combustion unit within the control of the
generator. However, we would note that the rendering process
``sufficiently processes'' the material into a non-waste fuel that
meets the legitimacy criteria, as we note above. Thus, the commenters
concern that non-waste determination petitions would need to be
submitted on a case-by-case basis, and would have a chilling effect on
the development of new customers and markets for processed fats, is not
the case. Thus, the final rule establishes these non-hazardous
secondary materials, after being processed, as a non-waste fuel.
---------------------------------------------------------------------------

    \140\ See the Preliminary Characterization Study Prepared In
Support of the Proposed Rulemaking--Identification of Nonhazardous
Secondary Materials That Are Solid Waste: Traditional Fuels and Key
Derivatives, EPA-HQ-RCRA-2008-0329-0461.21.
    \141\ See Adams, T.T., J. Walsh, M, Brown, J. Goodrum, J.
Sellers, and K. Das, 2002. ``A demonstration of Fat and Grease as an
Industrial Boiler Fuel,'' University of Georgia, Athens, GA.
---------------------------------------------------------------------------

C. Comments on Specific Materials Used as Ingredients

    The ANPRM identified a number of non-hazardous secondary materials
that the Agency believes are currently being used as legitimate non-
waste ingredients in combustion processes. The proposed rule then
identified the four material groups for which we received the majority
of the comments on the ANPRM. The four material groups are CKD, CCRs,
foundry sand, and blast furnace slag/steel slag. The proposed rule did
not assume that ingredients used in combustion units that are not
managed within the control of the generator are discarded materials (as
is the case for most non-hazardous secondary material fuels), since we
believe that non-hazardous secondary materials used as ingredients are
more akin to commodities managed within continuous commerce and are
used as an integral part of the manufacturing process. That is, non-
hazardous secondary materials that are directly used (or in the case of
previously used materials, reused), function as effective substitutes
(i.e., as raw materials) in normal manufacturing operations or as
products in normal commercial applications, and thus, EPA has
interpreted the definition of solid waste as excluding non-hazardous
secondary materials recycled in ways that most closely resemble normal
production processes, provided they meet the legitimacy criteria.
    Besides the comments on specific non-hazardous secondary materials
used as ingredients described below, we again note the overarching
comment that was raised by some commenters that the Agency has no
authority under section 129 of the CAA to regulate the use of secondary
materials as ingredients, as EPA's section 129 authority is limited to
``solid waste incineration units,'' which the statute defines as units
that ``combust'' solid waste. As discussed in Section V.A of today's
final rule, we believe that this comment is not relevant to this
regulation, which determines whether non-hazardous secondary material
is a solid waste, or not under RCRA. EPA has clear authority to
interpret RCRA to decide whether non-hazardous secondary materials are
solid wastes or not.
1. Cement Kiln Dust
    CKD is a fine-grained, solid, highly alkaline material removed from
the cement kiln exhaust gas by scrubbers. Much of the material
comprising CKD is incompletely reacted raw material, including a raw
mix at various stages of burning, and particles of clinker. Generation
of CKD is directly connected to the production of cement clinker. The
proposed rule indicated that CKD used in a cement kiln would not be
considered a solid waste when used as an ingredient in a combustion
unit, so long as it was not discarded in the first instance and
satisfies the legitimacy criteria for ingredients. Whether CKD remains
within the control of the generator or is transferred to another person
is not in and of itself indicative of discard, as discussed above. If
CKD has been discarded, however, its use as an ingredient in cement
kilns would be considered combustion of a solid waste, unless it has
been processed to produce a non-waste ingredient.

    Comment: We received limited comments on CKD. One commenter urged
EPA to state that CKD that is removed from on-site storage piles or
monofills should be considered a legitimate non-hazardous secondary
material and should not be considered a solid waste. The commenter
explains that while CKD may have been previously placed in storage
piles or even permitted solid waste management units (SWMUs), the
technology did not exist previously to reuse the material. However,
newer kiln systems can now use the CKD that has previously been
disposed of, and thus, these non-hazardous secondary materials (which
are ingredients in the manufacture of cement) should not be subject to
the CAA section 129 standards.
    EPA's Response: The commenter acknowledges that even though the CKD
has remained on-site, the intent or purpose of placing CKD in storage
piles or SWMUs was to dispose of them (i.e., discard). Additionally,
CKD that has been placed in storage piles in this manner would likely
not meet the legitimacy criterion of ``managed as a valuable
commodity.'' Thus, it would appear in this instance that CKD that has
been placed in storage piles for the purpose of disposal, even if on-
site, has been discarded and would be considered a solid waste if
burned in a combustion unit, unless the discarded CKD is processed into
a non-waste ingredient product. (See discussion elsewhere in today's
preamble regarding the reason why non-hazardous secondary materials
that have been discarded in the first instance are solid waste if
burned in a combustion unit, unless the non-hazardous secondary
material is processed into a non-waste ingredient product.) CKD that
has not been discarded in the first instance, however, and satisfies
the legitimacy criteria would not be considered a solid waste when used
as an ingredient.
2. Coal Combustion Residuals \142\
---------------------------------------------------------------------------

    \142\ In a separate rulemaking effort, EPA has proposed
regulations that will provide for the safe disposal and management
of coal combustion residuals from utility coal-fired power plants
(the ``Coal Combustion Residuals Proposed Rule''). The proposed rule
was published in the Federal Register on June 21, 2010. See 75 FR
35127. Today's final rule does not affect that rulemaking effort, as
our rule considers the use of coal combustion residuals in
combustion units as fuels or ingredients, while the coal combustion
residual proposed rule is concerned with the safe disposal and
management of these residuals in landfills and surface impoundments.
For more information on the coal combustion residual proposed rule,
see Docket ID No. EPA-HQ-RCRA-2009-0640.
---------------------------------------------------------------------------

    CCRs are formed during the coal-burning processes in power plants
and industrial boilers, and are produced in various forms (i.e., fly
ash, bottom ash, and boiler slag) that are categorized by the process
in which they are generated. The proposed rule indicated that CCRs used
as ingredients in combustion units would not be considered solid
wastes, provided they were not discarded in the first instance and
satisfy the legitimacy criteria.\143\ We also noted that CCRs can be
used both as an ingredient and as a fuel supplement and proposed that
the decision to treat them as a fuel or ingredient should be based on
the primary purpose of their use in a combustion unit. We took comment
on this approach, especially our characterization that the primary use
of CCRs in cement kilns is generally for their ingredient value, as
opposed to their fuel value.
---------------------------------------------------------------------------

    \143\ For a discussion of CCRs used as fuels in combustion
units, see Section V.B.9 of this final rule.
---------------------------------------------------------------------------

    The proposal also indicated that when CCRs are used for their
ingredient value, the transferring of these materials to another person
would not in and of itself be indicative of discard. However, to the
extent that CCRs have been discarded in the first instance, they would
have to be processed into a non-waste ingredient product and satisfy
the legitimacy criteria in order not to be considered a solid waste. We
also noted that comments were submitted on the ANPRM, which described
patented processes that remove unwanted carbon from coal fly ash in
order for these non-hazardous secondary materials to be used as an
ingredient. While these processes--that is, those that separate carbon
from fly ash to produce technically compliant fly ash for use in
concrete appear to satisfy our processing requirement, we requested
that commenters provide additional information explaining how this
processing is conducted, and whether this type of fly ash is used as an
ingredient in the clinker production process. The proposed rule also
requested comment on the extent to which CCRs are recovered from the
discard environment (e.g., landfills) and used as ingredients in cement
kilns, as well as more information on the extent to which these CCRs
are processed.
    In addressing the commenter who submitted comments on the ANPRM and
argued that CCRs are solid wastes due to their high concentration of
contaminants, the proposal noted that the chemical properties of CCRs
are influenced to a great extent by the coal burned, the type of
combustion unit, and the air pollution controls applied.\144\
Acknowledging that fly ash may contain various levels of metals, such
as vanadium, zinc, copper, chromium, nickel, lead, arsenic, and
mercury,\145\ the proposed rule noted that in a 2008 Report to Congress
addressing the use of these secondary materials as ingredients in
cement and concrete applications, the overall conclusion reached with
respect to the perceived safety health risk barriers was a positive
one, in that the risk analyses did not identify significant risks to
human health and the environment associated with these uses.\146\
---------------------------------------------------------------------------

    \144\ For more information on the different types, or ranks, of
coal, please refer to the Materials Characterization Paper on
Traditional Fuels and Key Derivatives, which is located in the
docket of today's final rule.
    \145\ See ``Technical Background Document for the Report to
Congress on Removing Wastes from Fossil Fuel Combustion: Waste
Characterization.'' U.S. EPA. March 15, 1999.
    \146\ ``Study on Increasing the Usage of Recovered Mineral
Components in Federally Funded Projects Involving Procurement of
Cement or Concrete to Address the Safe, Accountable, Flexible,
Efficient Transportation Equity Act: A Legacy for Users. Report to
Congress.'' June, 3, 2008. EPA530-R-08-007. When analyzing perceived
safety and health risk barriers associated with the beneficial use
of recovered mineral components (including CCRs et al.), this study
concluded that ``Findings from [several cited] analyses did not
identify significant risks to human health and the environment
associated with the beneficial uses of concern. In addition, [EPA]
identified no documents providing evidence of damage to human health
and the environment from these beneficial uses. Our overall
conclusions from these efforts, therefore, are that encapsulated
applications, including cement and concrete uses, appear to present
minimal risk.'' Id. at 4-11.
---------------------------------------------------------------------------

    The proposed rule also noted that the Agency is studying the
possible effects of new air emission control technologies and
configurations on the composition of CCRs and requested comment on
whether advanced emission control technologies, such as carbon control
technologies for mercury and NOX, are resulting or will
result in increased levels of contaminants in coal ash to the extent
that coal ash would not satisfy our legitimacy criteria.
    Comment: Almost all commenters agreed that the primary purpose when
using CCRs in cement kilns was to utilize these secondary materials as
ingredients. Most commenters further asserted that all CCRs, when used
in combustion units, should always be classified as ingredients rather
than as fuels. (See Section V.B.9 for a further discussion on this
comment and the Agency's response.) These commenters claimed that any
energy value that is recovered is secondary to its value as an
ingredient, and argued that classifying CCRs always as ingredients
would simplify the waste determinations for these non-hazardous
secondary

materials by clearly establishing the appropriate legitimacy criteria
that apply (i.e., facilities would not need to determine whether the
fuel or ingredient legitimacy criteria apply based on the primary
purpose of the secondary materials).
    Some commenters were also concerned that if cement kilns burned
high-carbon content fly ash (which has more pronounced fuel content),
the provisions of this rule applying to fuels would be triggered, even
though these secondary materials have nearly identical characteristics,
is managed in an identical manner, and is combusted in the same unit as
the material used primarily as an ingredient (i.e., low-carbon content
fly ash).
    EPA's Response: EPA agrees with the commenters that the primary
purpose when using CCRs in cement kilns is to utilize it as an
ingredient. However, we disagree with those commenters that argued that
all CCRs, when used in combustion units, should be categorically
defined as ingredients. As some commenters acknowledged (and as we also
discussed in Section V.B.9 above), some CCRs are indeed used for their
fuel value as opposed to their ingredient value, especially when re-
burned, as in the case of their use in combustion units by electric
utilities. Therefore, we cannot categorically classify CCRs as
ingredients when it is clear that, in some cases, these non-hazardous
secondary materials are being burned for their fuel value and/or to
produce a new secondary material (i.e., low-carbon fly ash). In cases
where the primary purpose of using CCRs is for their fuel value and not
for their ingredient value (e.g., by electric utilities), the secondary
materials must meet the requirements for fuels, including the
legitimacy criteria, in order not to be considered a solid waste.
    With respect to the issue of high-carbon fly ash burned in cement
kilns, it is not clear the extent to which cement kilns burn high-
carbon fly ash or rather if commenters were providing a hypothetical
situation in order to highlight potential issues that could arise for
secondary materials that could have value as both a fuel and
ingredient. It is also unclear whether low-carbon fly ash is required
as a substitute ingredient in Portland cement or if cement kilns can
also use high-carbon fly ash for its ingredient value. To the extent
that these kilns are burning these secondary materials for their fuel
value as opposed to their value as an ingredient, these secondary
materials would be subject to the requirements for non-hazardous
secondary materials used as fuels promulgated in today's final rule.
    We note other commenters who describe processes for removing
unwanted carbon from fly ash in order to produce concrete quality fly
ash (lower carbon content), which could suggest that cement kilns that
burn high-carbon fly ash may be using these secondary materials for
their fuel value, as well as their ingredient value. These commenters,
however, discussed instances where fly ash was used as a fuel only in
regards to its use in utility boilers and CBO units--where there is
clearly not an ingredient value, as is the case with burning fly ash in
cement kilns.
    Comment: EPA received comments on the ANPRM stating that there are
at least four patented processes for removing unwanted carbon from fly
and bottom ash that allow the processed ash to produce both technically
compliant ash for use in concrete and a separate carbon stream that can
be re-introduced into the boiler for its fuel value. One electric
utility, commenting on the proposed rule, also mentioned patented
processes for using CCRs recovered from landfills. However, neither of
these commenters provided specific details regarding how CCRs that are
recovered from the discard environment are actually ``processed.'' One
other commenter discussed a two-stage process to maintain low carbon
content, but was not aware whether the material was used for concrete
or clinker production. Another commenter argued that the same processes
used for currently generated fly ash to separate high-carbon ash from
mineral ash could be applied to reclaimed fly ash and produce similar
secondary ingredients. This commenter argued that the processes produce
two materials that are chemically distinct from the reclaimed fly ash
and should therefore satisfy our proposed processing requirement.
    EPA's Response: Unfortunately, EPA did not receive information
during the comment period describing the types of processing that
discarded CCRs undergo prior to being used as an ingredient in a
combustion unit and are, thus, unable to make a categorical
determination whether the patented processes referenced in the proposed
rule would meet the definition of processing being promulgated in
today's final rule. Although we did not receive new information
regarding how CCRs are processed, as we stated in the proposed rule,
certain processes are currently being utilized to recover CCRs from the
discard environment that would likely meet our definition of
``processing.'' For example, we are aware of at least one electric
utility that recovers ash from ponds or landfills and then separates
this secondary material into its fundamental components: Carbon,
silicates, and high-density, iron-rich materials. A coarse carbon-fuel
product is then recovered by density separation using concentrating
spirals. A fine carbon-fuel product is also recovered with flotation
cells.\147\ We believe that this type of processing is likely to meet
our definition of processing, as it appears that these processes in
fact remove contaminants and improve the ingredient characteristics of
these recovered CCRs. Thus, a determination would need to be made as to
whether such processes meet the definition of processing, as codified
in Sec.  241.2.
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    \147\ See ``Materials Characterization Paper on Coal Combustion
Residuals--Coal Fly Ash, Bottom Ash, and Boiler Slag.'' A copy of
this document has been placed in the docket for today's rule.
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    Comment: As noted above, we solicited comments in the proposed rule
regarding the extent to which CCRs are recovered from the discard
environment and used as ingredients in cement kilns. We received a few
comments regarding the extent to which CCRs are mined from landfills
(i.e., recovered from the discard environment). Most of these comments
did not specify, however, whether these recovered CCRs were
subsequently used for their fuel or ingredient value.
    EPA's Response: Based on the comments, it does not appear that it
is a common practice for CCRs to be recovered from the discard
environment (e.g., landfills) and beneficially used. We respond to
these comments in Section V.B.9 (Comments on Specific Materials Used as
Fuel-Coal Combustion Residuals).
    Comment: Regarding the question of whether advanced emission
control technologies are resulting or will result in increased levels
of contaminants in CCRs, one commenter stated that there was no
credible way to know or anticipate this information. Another commenter
agreed, stating that there is no data and no way to predict the result
of new or future technology on the character of fly ash because of the
use of advanced pollution control technology. This commenter also notes
that there is no current information available that has proven that
advanced emission control technologies directly result in increased
contaminant levels.
    One state commenter, however, stated that it expects the mercury
content of coal fly ash to increase significantly in upcoming years.
Consequently, this state commenter described its current efforts to
remove a generic, pre-determined beneficial use determination for coal
fly ash as an ingredient in

cement manufacturing. Additionally, another commenter stated that when
using the CBO process to combust fly ash, essentially 100 percent of
the mercury entering the CBO unit as feed ash leaves with the product
ash.
    EPA's Response: EPA recognizes that it is difficult to anticipate
what contaminant levels in coal fly ash will result from implementation
of future technologies. We also believe, however, that it is important
to be studying and anticipating the possible effects of new air
pollution control (APC) technologies and configurations on the
composition of CCRs to the greatest extent possible. As noted in the
proposed rulemaking, EPA has begun publishing a series of reports to
analyze this issue further.\148\ Based on these reports, EPA believes
that changes to APCs at coal-fired power plants (e.g., addition of
flue-gas desulfurization (FGD) systems, selective catalytic reduction,
and activated carbon injection to capture mercury and other pollutants)
are shifting mercury and other pollutants (e.g., metals) from the flue
gas to fly ash, FGD gypsum, and other APC residues. The Agency will
continue to research the possible effects of APCs on contaminant levels
in fly ash. We note that under today's final rule, fly ash used as an
ingredient would need to pass the contaminant legitimacy criterion for
ingredients in order to not be considered a solid waste.\149\
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    \148\ A series of reports have been and are being developed by
U.S. EPA's Office of Research Development. To date, three documents
have been finalized, including: (1) ``Characterization of Mercury-
Enriched Coal Combustion Residuals from Electric Utilities Using
Enhanced Sorbents for Mercury Control.'' EPA-600/R-06/008. Feb.
2006; (2) ``Characterization of Coal Combustion Residuals from
Electric Utilities Using Wet Scrubbers for Multi-Pollutant
Control.'' EPA-600/R-08/077. July 2008; and (3) ``Characterization
of Coal Combustion Residuals from Electric Utilities Using Multi-
Pollutant Control Technology--Leaching and Characterization Data.''
EPA-600/R-09/151. December 2009. Ongoing work to complete this
research includes: (1) Probabilistic assessment of the leaching
source term for plausible CCR management scenarios, (2) Leach-XS
Lite which is free software providing electronic access to data from
this research, and (3) test methods for the Leaching Environmental
Assessment Framework (LEAF).
    \149\ We also note that CCRs used as fuels must also meet the
contaminant legitimacy criterion in order not to be considered a
solid waste.
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3. Foundry Sand
    Foundry sand is an industrial material generated by the metal-
casting industry, which uses the sand to form a physical mold used in
the production of metal products. After multiple uses in castings, the
sand becomes unsuitable for castings and is either disposed of in
landfills or beneficially used in other applications, including use as
an ingredient in the manufacture of Portland cement. The proposed rule
classified foundry sand as not being a solid waste when used as an
ingredient in a combustion unit, so long as it was not discarded in the
first instance and satisfies the legitimacy criteria for ingredients.
Whether foundry sand remains within the control of the generator or is
transferred to another person is not in and of itself indicative of
discard, as discussed previously. If foundry sand has been discarded,
however, it would be considered a solid waste, unless it has been
processed to produce a non-waste ingredient.
    Comment: We received a few comments regarding the characterization
of foundry sand in the proposed rule. One commenter discussed how
foundry sand is reused in the metal casting process as part of its
argument that foundry sand should not be considered a solid waste,
citing a 2001 letter from EPA which indicated that foundry sand reused
on-site within the sand loop for mold making is part of a continuous
industrial process and, therefore, not a solid waste.\150\ The same
commenter also discussed how this sand can also be processed on-site in
a thermal reclamation unit so that the sand can be returned to the
mold- and core-making process. Commenters also discussed a variety of
other beneficial uses for foundry sand.
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    \150\ March 28, 2001 letter from Elizabeth Cotsworth, Director,
EPA's Office of Solid Waste to Ms. Amy J. Blankenbiller, American
Foundry Society. A copy of this letter can be found in the docket to
today's rule.
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    EPA's Response: The foundry sand uses evaluated as part of this
rulemaking only include their use as an ingredient in combustion, such
as cement kilns. We do not consider the reuse of foundry sand in the
metal casting operations to constitute the use of a non-hazardous
secondary material either as a fuel or ingredient in a combustion
system, but rather as a type of beneficial use that is routinely
employed by foundries in the production of metal products. As we stated
in the referenced 2001 letter, foundry sands that are re-used on-site
in the primary production process on a continuous basis in the sand
loop are not solid wastes.\151\
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    \151\ For more information on the reuse of foundry sands as
molds, see ``Revisions to the Definition of Solid Waste'' Final Rule
at 73 FR 64705. October 30, 2010.
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    We note, however, that the 2001 letter cited by one commenter
explicitly states that the Agency is not addressing the status of any
thermal processing of sand in the letter. It appears that the purpose
of ``processing'' foundry sand in a thermal reclamation unit is to
destroy or dispose of the contaminants so that the foundry sand can be
re-used. As such, the burning of foundry sand in a thermal reclamation
unit is burning for discard and, thus, would be considered a solid
waste if combusted in such a unit, which would be subject to the
section 129 CAA standards. Regarding comments that discussed other
beneficial uses of foundry sand, we again note that this rule is
limited to situations where the non-hazardous secondary material is
used as a fuel or ingredient in a combustion unit and, as such, other
examples of using foundry sand in other applications is beyond the
scope of this rulemaking.
4. Blast Furnace Slag/Steel Slag
    Blast furnace slag and steel furnace slag (steel slag) are by-
products of iron and steel manufacturing in both iron and steel mills.
Slags are used as ingredients in cement clinker manufacturing,
bituminous concrete, road building and construction, among other
beneficial uses. The proposed rule indicated that blast furnace and
steel slag used as ingredients in combustion units that are not
discarded in the first instance would not be considered a solid waste
provided they satisfy the legitimacy criteria for ingredients. Whether
blast furnace and steel slag remains within the control of the
generator or is transferred to another person is not in and of itself
indicative of discard, as previously discussed. However, if blast
furnace and steel slag are in fact discarded in the first instance,
then they would have to be sufficiently processed into a non-waste
ingredient that satisfies the legitimacy criteria in order to be
classified as a non-waste ingredient. However, we solicited comments on
the level of processing that these materials undergo before determining
whether such operations would meet our definition of processing.
    Comment: We received few comments specifically on blast furnace and
steel slag. One commenter discussed the use of blast furnace slag as a
raw material substitute in the glass manufacturing process. Another
commenter discussed how blast furnace and steel slag are typically
returned to the iron and steel making processes and are not discarded
in the first instance. The same commenter also discussed slag piles
that were previously discarded and the processing that these non-
hazardous secondary materials go through. Specifically, such processing
includes extraction, passing the slag through grizzlies, removal of
iron bearing scrap using magnets, and then screening to

size the aggregate. Some commenters also asserted that because these
slags are reused as part of a continuous process, the application of
the legitimacy criteria are inappropriate.
    EPA's Response: We agree with the commenters that blast furnace and
steel slag that are reused as an ingredient, either in the iron and
steel making processes or in the manufacturing of glass, are not solid
wastes provided they have not been discarded in the first instance and
meet the legitimacy criteria. However, we disagree with the commenters,
who argued that because they are reusing these slags in a ``continuous
process,'' the application of the legitimacy criteria do not apply. EPA
has a long-standing policy that the recycling of secondary materials,
both hazardous and non-hazardous, including as part of a continuous
industrial process, must be legitimate. The legitimacy provisions in
today's rule are designed to distinguish between real recycling
activities and ``sham'' recycling, an activity undertaken by an entity
to avoid certain requirements, which in this case would be to avoid
triggering the section 129 CAA requirements for solid waste
incinerators. Because of the economic advantages in managing the non-
hazardous secondary material as a non-waste ingredient as opposed to a
solid waste ingredient, there is an incentive for some handlers to
claim they are recycling, when, in fact, they are conducting waste
disposal. Therefore, blast furnace and steel slag used as an ingredient
in a combustion unit, including as part of a continuous industrial
process, must satisfy all of the legitimacy criteria in order to not be
considered a solid waste.
    Regarding the description provided by the commenter on the extent
of processing conducted on slags that have been previously discarded,
it appears that this level of processing would meet our definition of
processing, as the processing includes not only rigorous operations to
extract the slag from the discard environment, but also the concerted
removal of constituents through magnetic separation. Assuming the
processed slag meets the legitimacy criteria for ingredients, the slag
resulting from the processing operation would constitute a non-waste
ingredient and would not be considered a solid waste.

D. Comments on Legitimacy Criteria for Fuels

    Non-hazardous secondary materials used as fuels in combustion units
must meet the legitimacy criteria specified in Sec.  241.3(d)(1) in
order to be considered a non-waste fuel. To meet the fuel legitimacy
criteria, the non-hazardous secondary material must be managed as a
valuable commodity, have a meaningful heating value and be used as a
fuel in a combustion unit that recovers energy, and contain
contaminants at levels comparable to or lower than those in traditional
fuels which the combustion unit is designed to burn. Details on each
criterion as outlined in the proposed rule and the comments received
are discussed below.
1. Managed as a Valuable Commodity
    Under the proposed rule, non-hazardous secondary materials used as
fuels must be managed as valuable commodities, including being stored
for a reasonable time frame. Where there is an analogous fuel, the non-
hazardous secondary material used as a fuel must be managed in a manner
consistent with the management of the analogous fuel or otherwise be