emissions levels achieved by best performing sources no matter what
means they use to achieve them. This approach is supported by the DC
Circuit's decision in the Brick MACT case, which stressed the
importance of identifying emissions ``levels'' achieved by sources.
There can be no dispute that both the composition and level of
emissions exiting the incinerator reflect both the add-on control
technologies used by a unit (e.g., dry scrubber, wet scrubber,
activated carbon) that control the emissions and the non-technology
factors (e.g., waste material quantity and composition, combustion
conditions) that influence the level and composition of emissions. As
the Sierra Club Court noted in 1999, the less mercury fed into the
waste stream, the less mercury emissions will be coming out of the
stack. Whatever combination of add-on controls and non-technology
measures a unit is employing will, therefore, necessarily affect the
resulting emissions levels that are reflected in the actual emissions
data upon which the revised floors are set. It would be impossible for
those data to not reflect all those measures. This situation is quite
the opposite of what was presented in the 1997 rulemaking, in which the
floors were primarily derived from permit and regulatory levels that
were not necessarily reflective of actual emissions performance but
were assumed to reflect levels achievable by add-on control only. At
that time, to adjust floors downward to account for non-technology
factors, it might indeed have been necessary to be able to quantify
additional emissions reductions attributable to such measures.
Similarly, as the 2007 proposed remand response still in large part
relied upon the permit and regulatory levels, not knowing the
quantified reductions achieved by non-technology measures frustrated
estimating the emissions levels achieved in practice by HMIWI. But this
is simply not an issue under a methodology that depends upon the
measured emissions levels that result from whatever mix of add-on or
non-technology controls is being used, as under the 2008 re-proposal
and today's final rule. The non-technology factors cannot help but
affect the actual emissions data, and they are, therefore, necessarily
accounted for in the actual emissions data-based floors.
    EPA's data gathering effort for this rulemaking included not just
initial and annual emissions test data obtained from EPA Regions,
State/local governments, and HMIWI facilities, but also a waste
segregation practices questionnaire sent to nine representative
entities in the HMIWI category (six hospitals, one pharmaceutical
facility, one university, and one company that owns 8 of the 14
commercial HMIWI). (See 2008 memoranda entitled ``Documentation of
HMIWI Test Data Database'' and ``Summary of Industry Responses to HMIWI
Waste Segregation Information Collection Request,'' which are included
in the docket.) While our analysis of the emissions test data indicates
a strong relationship between add-on control and emissions (e.g., wet
scrubbers achieve superior HCl control, while dry scrubbers achieve
superior PM and metals control), our review of the questionnaire
responses indicates that non-technology factors also play a role in
emissions reduction. All of the survey respondents, except for the
commercial company, practice onsite waste segregation to reduce the
volume of waste being incinerated. Most of the respondents started the
practice of waste segregation in the 1980s and 1990s. Five respondents
also accept offsite waste and require the offsite waste generators to
employ waste segregation practices. The commercial company encourages
waste segregation from its waste generator clients through a number of
efforts, including a waste management plan, contract requirements and
waste acceptance protocols, a dental waste management program, and
educational programs and supporting posters. All of the respondents
that practice onsite waste segregation separate batteries and
fluorescent bulbs (i.e., mercury waste) from the HMI waste stream.
Eight respondents separate paper and/or cardboard, four separate glass,
and three separate plastics from the HMI waste stream. Other materials
that are separated from the HMI waste stream include hazardous waste,
waste oil, wood, construction debris, refrigerants, and various metals
and metals-containing materials (e.g., aluminum, copper, lead, mercury,
steel, and electronics). (For further information, see 2008 memorandum
``Summary of Industry Responses to HMIWI Waste Segregation Information
Collection Request,'' which is included in the docket.) These waste
segregation efforts would certainly have an impact on the emissions of
CDD/CDF, mercury, and other pollutants from these HMIWI and would be
reflected in the emissions levels measured during their initial and
annual emissions tests and used in our test data analysis. As noted
previously, the nine entities surveyed were believed to be
representative of the HMIWI industry as a whole, so the conclusions
reached for the nine entities are also expected to apply to the entire
industry as well.
5. Straight Emissions Approach
    Comment: Two commenters argued that the parenthetical language in
the Brick MACT decision equating the best performers with ``those with
the lowest emissions levels'' (straight emissions approach) was only a
legal dictum to

which EPA is not bound, and which is not cited in either the CKRC
decision or the CAA. The commenters cited Sierra Club v. EPA, 479 F.3d
875, 880 (DC Cir. 2007) (Brick MACT), and Cement Kiln Recycling
Coalition v. EPA, 255 F.3d 855, 861 (DC Cir. 2001). In citing EPA's
justification for the MACT floor approach used in the hazardous waste
combustor rulemaking, the commenters stated EPA's position that the CAA
does not require the Agency to equate the best performers with the
lowest emitters. The commenters specifically cited EPA's statement
that, ``as a legal matter, CAA Section 112(d)(3) does not specifically
address the question of whether `best performing' sources are those
with the lowest net emissions, or those which control HAP emissions
most efficiently.''
    The commenters also noted that, since the Brick MACT decision, EPA
has determined that there are other ways to rank the best performing
sources and set the MACT floors than a straight emissions approach,
such as the approach used in the hazardous waste combustor rulemaking,
which combined the hazardous waste fed to the source and the source's
system removal efficiency (SRE). According to the commenters, the ``SRE
Feed'' methodology better identifies who the lowest emitters will be
over time, better assesses their performance (i.e., how much they will
emit as they operate), and better accounts for variability (e.g., non-
technology factors).
    Response: It is not necessary to adopt a position regarding whether
the Brick MACT Court's references to ``emissions levels'' is dictum or
binding for purposes of this rulemaking. In the 1999 HMIWI case, the
Court very clearly stated that EPA's duty here was to use data that
allowed the Agency to reasonably estimate the emissions performance of
the best performing units. We have discovered that the permit and
regulatory data upon which the 1997 rule was based do not reliably
serve this purpose. Conversely, the actual emissions data from HMIWI do
enable us to estimate the performance of the best performers. We
believe that the use of actual emissions data, appropriately adjusted
for variability using statistical methods, sufficiently accounts for
the performance and variability of HMIWI operation. Regarding the
commenters' reference to CAA Section 112(d)(3) to support their
argument regarding the definition of ``best performing'' sources, we
assume the commenters also meant Section 129, which governs this rule.
    We do not think the SRE Feed methodology can be successfully
adapted to determine MACT floors for HMIWI. This is because the SRE
Feed approach requires knowledge of the amount of hazardous materials
fed into the system and knowledge of the system's removal efficiency
for those specific materials, neither of which is known or measured in
the HMIWI industry. Such materials are mixed in with other waste and
cannot reasonably be measured separately, especially given the
occupational safety regulations to which HMIWI operators are subject.
6. Statistical Approach
    Comment: Multiple commenters stated that the statistical
methodology EPA used to establish MACT floors did not properly account
for underlying non-technology factors such as feed material quantity or
composition or for normal operational variability within and across
unit operations, which led to unattainable emissions limits.
    Three of those commenters supported the conditional use of the 99.9
percent UCL to quantify ``emissions limitation achieved'' as it applies
to variability above average emissions. However, the three commenters
had concerns about EPA's methods used to calculate statistical
parameters. The commenters stated that EPA should characterize
emissions data distributions before calculating statistics, instead of
assuming all data are normally distributed. Otherwise, according to the
commenters, it is difficult to determine if the statistics are valid.
When data are not normally distributed, the commenters recommended that
EPA transform the data prior to conducting its statistical
calculations. The commenters noted that EPA used the NORMSINV function
in Microsoft Excel to calculate the 99.9 percent UCL, which assumes
that the actual mean and variance of a data set is known. According to
the commenters, when the mean and variance are estimated from random
samples or a small subset of the total population, such as stack test
runs, the 99.9 percent UCL should be calculated with the Student t-
statistic using the TINV function in Excel, not normal statistics.
    Two other commenters objected to the use of the 99.9 percent UCL to
account for variability in determining emissions limits. One of the
commenters argued that EPA provides insufficient explanation or
justification of its use of the 99.9 percent UCL. According to the
commenter, if the performance of the best performing HMIWI, on average,
is estimated to meet the emissions limit 99.9 percent of the time, then
it would be expected to exceed the emissions limit 8.76 hours per year,
which does not comply with the requirement that each source must meet
the specified floor every day and under all operating conditions.
Therefore, the commenter argued that the 99.9 percent UCL procedure
used by EPA is deficient and must be revised.
    The other commenter stated that EPA's use of a 99.9 percent UCL to
estimate individual units' variability marks a sharp departure from
EPA's approach in other rulemakings (e.g., 90 percent and 95 percent
UCL), and said that EPA offers no real explanation for this departure
from past practice or why a 99.9 percent UCL would account for
variability but a lower UCL, such as 99 percent or 95 percent or 90
percent, would not. The commenter recommended that EPA correct its
floor approach to avoid the overcompensation for variability seen with
some of the floors for new units.
    Two commenters stated that a more realistic assessment of an
individual unit's ability to meet an emissions limit during a
compliance test would use the 99.9 percent UCL for that unit/pollutant
instead of the average value.
    Four commenters disagreed with EPA's decision to use individual
test run results to account for variability in setting MACT floors for
new and existing sources. The commenters urged EPA to use complete
performance test results instead. One of the commenters argued that EPA
is arbitrarily using different measures of performance for establishing
emissions standards on the one hand (using test runs) and measuring
compliance with these standards on the other (using whole tests),
without explaining why different measurement approaches are
appropriate. According to the commenter, it appears likely that
disaggregating test results leads to less protective floors by creating
false variability in individual units' performance. The commenter
recommended that EPA calculate the floors with and without
disaggregating individual test runs to ensure that its floors are not
less stringent as a result of that approach. The other commenters noted
that data limitations may not leave EPA an alternative to using test
run results in some cases, but they recommended that EPA use complete
test results where enough data exist to characterize emissions
variability.
    Response: Based on the responses to our waste segregation practices
questionnaire, we believe that most HMIWI are practicing (or
encouraging the practice of) waste segregation of materials such as
batteries, fluorescent bulbs, paper, glass, plastics, and metals-
containing materials, which we expect

to impact the emissions of CDD/CDF, mercury, and other pollutants and
be reflected in the actual emissions data we use in our analysis. (See
2008 memorandum ``Summary of Industry Responses to HMIWI Waste
Segregation Information Collection Request,'' which is included in the
docket.) Consequently, we believe that using actual emissions data
sufficiently and inherently accounts for non-technology factors such as
feed material quantity or composition which influence the level and
composition of emissions. We also believe that our use of multiple
emissions tests and individual test runs for each HMIWI, where
possible, and our estimation of 99 percent confidence intervals for
MACT floor data sufficiently accounts for variability. The use of
multiple emissions tests allows us to evaluate ``between-test
variability,'' which can occur even where conditions appear to be the
same when two or more tests are conducted. As we noted in the preamble
to the December 1, 2008 re-proposal (73 FR 72976, 72980), variations in
emissions may be caused by different settings for emissions testing
equipment, different field teams conducting the testing, differences in
sample handling, or different laboratories analyzing the results.
Identifying an achieved emissions level needs to account for these
differences between tests, in order for ``a uniform standard [to] be
capable of being met under most adverse conditions which can reasonably
be expected to recur[.]'' (See NLA I, 627 F.2d at 431, n. 46.) (See
also Portland Cement Ass'n, 486 F.2d at 396 (noting industry point that
``a single test offered a weak basis'' for inferring that plants could
meet the standards).) The use of individual test runs (as opposed to
test averages or unit averages) allows us to evaluate ``within-test
variability.'' A single test at a unit usually includes at least three
separate test runs. (See Sec.  63.7(e)(3) (for MACT standards under
Section 112 of the CAA), and Sec.  60.8(f) (for NSPS under CAA Section
111).) Each data point should be viewed as a snapshot of actual
performance. Along with an understanding of the factors that may affect
performance, each of these snapshots gives information about the
normal, and unavoidable, variation in emissions that would be expected
to recur over time. To account for pollutant-specific variability at
the best-performing unit (for new source MACT) or best-performing 12
percent of units (for existing source MACT), we used emissions data for
each test run conducted by those units. The amount of pollutant-
specific test data for those HMIWI varies widely for each size
category. Given the limited amount of test data and the uncertainty
regarding that short-term emissions test data, we have decided that
using the 99 percent UCL is an appropriate method of estimating
variability. The UCL represents the statistical likelihood that a
value, in this case an emissions value from the best performing source,
will fall at or below the UCL value. (Further discussion regarding the
99 percent UCL is provided later in this section.)
    After reviewing the commenters' suggestion that we characterize
emissions data distributions before calculating statistics, we took a
closer look at our statistical approach. In statistics, skewness is a
measure of the degree of asymmetry of a distribution. Normal
distributions typically have a skewness of zero. Consequently, to
determine whether the emissions test data used in our UCL calculations
had a normal or lognormal distribution, we estimated the skewness of
the data using the SKEW function in Excel. Except as specified below,
those datasets with a skewness value greater than zero (when rounded to
a whole number) were categorized as lognormal, and all other datasets
were categorized as normal. Those data categorized as lognormal were
transformed (by taking the natural log of the data) prior to the
calculation of UCL values. When there were only a few data points
(e.g., one emissions test with three test runs), which is the case for
most datasets for small HMIWI, it was not possible to make a definitive
determination that the data were distributed normally or lognormally.
(In fact, assuming a lognormal distribution for those data often
resulted in UCL values that were substantially higher than the 1997
promulgated limits.) In those cases, we decided to use the normal
distribution in calculating UCL values, a conservative assumption which
provided a more protective emissions limit. When we had more data and
could make a more definitive determination about a dataset's
distribution, we treated the data as noted previously. In most cases,
we found that the larger datasets are lognormally distributed, although
there are some cases where they appear to be distributed normally, and
we treated the data as such when doing our UCL calculations. We believe
this approach is more accurate and obtained more representative results
than those at re-proposal.
    Regarding the commenters' suggestion about using Student's t-
statistics in calculating the UCL values, we also decided to revisit
our statistical approach. We agree that we have only a relatively
small, random sample of emissions data available for our analysis,
which calls for the use of the Student's t-test, in accordance with
standard statistical practice. Consequently, we have decided to use the
TINV function in Excel (specifically the one-tailed t-value), rather
than the NORMSINV function, to calculate the UCL values. This approach
(using the Student's t-test) is consistent with approaches being taken
in other EPA rulemakings, such as Portland Cement.
    In response to public comments on the size of the confidence limits
used at re-proposal and in light of the aforementioned changes in our
statistical approach, we also decided to reevaluate the percentiles
used in the UCL values. We evaluated four different percentiles (90,
95, 99, and 99.9 percent). The 99.9 percent UCL values estimated for
the 2009 final rule are substantially higher than the highest test runs
for the MACT floor units and are frequently higher than the emissions
limits in the September 15, 1997 promulgated standards, indicating the
99.9th percentile overcompensates for variability. Lower percentiles
(e.g., 90, 95, and 99 percent) are inherently more stable than the
99.9th percentile, with less uncertainty (less variability) than the
99.9th percentile from a statistical standpoint. However, the 90 and 95
percent UCL values are frequently lower than the highest test runs for
the MACT floor units and the stringent emissions limits in the December
1, 2008 re-proposal, indicating that those percentiles provide
insufficient compensation for variability.
    The 99 percent UCL values are somewhat higher than the emissions
limits in the December 1, 2008 re-proposal but are well below the
emissions limits in the September 15, 1997 promulgated standards. The
99 percent UCL values are more in line with the highest test runs for
the MACT floor units than the other percentiles, indicating that the 99
percent UCL provides a more reasonable compensation for variability.
This approach results in standards more representative of the level of
emissions reduction that the best performing sources are actually
achieving. Accordingly, we have decided to use the 99 percent UCL to
estimate emissions limits for the 2009 final rule.
    We disagree with one commenter's argument that the 99.9 percent UCL
must provide for the floor to be met every day and under all operating
conditions. The UCL is not about time, but about the population of
data. Accounting for variability using the 99.9 percent UCL goes beyond
the absolute

average but does not produce expectations of 0.1 percent noncompliance.
Setting the emissions limit at the UCL accounts for the possibility of
variability and the possibility that the average is outside the range.
These statistical procedures are used to help us identify the average
emissions limitation achieved by the best performing units, as Section
129(a)(2) of the CAA requires. Also, there is no practical upper limit
as to what a facility can emit, so the argument that that EPA must set
a floor at a level that equates to what a facility can meet at all
times is not consistent with the CAA's requirement that EPA estimate
the emissions levels achieved by best performing units.
    Regarding the comment about our decision to use individual test run
results to account for variability, we felt it was necessary to use
test run results when we had data limitations (e.g., for small HMIWI)
and for consistency decided to take the same approach where data were
more plentiful. As noted previously, we believe that each data point
should be viewed as a snapshot of actual performance, which gives
information about the variation in emissions that would be expected to
recur over time.

D. Emissions Limits

1. HCl, CDD/CDF, and Metals Emissions Limits
    Comment: One commenter argued that EPA's proposed HCl standards of
2.4 parts per million by volume (ppmv) for existing sources and 0.75
ppmv for new sources are based on biased data of indeterminate quality
and are unachievable. The commenter also claimed that setting the HCl
standards at such low levels will negatively impact the development and
application of CEMS, due to the lack of correlation between Method 26A
and CEMS at concentrations comparable to the proposed standards.
According to the commenter, the test results (Methods 26 and 26A and
RCRA SW 846 Method 0050) that EPA used to set the HCl standards contain
a known bias at low levels of HCl, varying widely with temperature and
moisture at HCl levels below 20 ppmv (all three methods), and having a
negative bias at HCl levels below 5 ppmv (Method 26A). The commenter
noted that all of the top performers in the large, medium, and small
non-rural categories use wet scrubbers to control HCl emissions, and
will have considerable moisture in the stack gas. Thus, the data from
every one of these sources has the potential to be biased. The
commenter argued that HCl data below 20 ppmv are not usable and/or
representative and are technically indefensible. The commenter
recommended that EPA follow the example of Office of Solid Waste (OSW),
which corrected all HCl values below 20 ppmv to 20 ppmv, used a
statistical method to impute a standard deviation for these test runs,
and calculated a floor standard based on those values.
    Response: We are basing the HCl standards in this rulemaking on the
data we have available to us from the HMIWI source category, and can
base them only on that data. The sensitivity of Method 26A for HCl is
0.04 ppmv. Moisture is only an issue with Method 26A if the testing
contractor does not perform the method correctly. Unless we are given
data to the contrary, we assume that the HCl data in our dataset are
correct. These data, for this particular rulemaking, support the HCl
standards being adopted today.
    Nonetheless, we acknowledge that the HCl standards in our re-
proposal were very close to the method detection limit for HCl. The
changes in statistical approach for the final rule have resulted in
increases to the HCl standards above 5 ppmv, which should address some
of the concerns listed above. Furthermore, based on reported HCl
emissions data for all HMIWI, we estimate that 64 percent of large, 82
percent of medium, and 100 percent of small/small rural HMIWI will be
capable of meeting the revised HCl standards, on average, based on
their currently used control measures. It should also be noted that
HMIWI subject to the 1997 NSPS have been meeting the 15 ppmv HCl
standard in that rule, which is below the 20 ppmv threshold level that
the commenter cited.
    Comment: One commenter recommended that EPA set beyond-the-floor
standards for both HCl and chlorinated organic pollutants (including
CDD/CDF) based on removing chlorinated plastics from the waste stream.
According to the commenter, it is well established that the combustion
of chlorinated plastics increases emissions of HCl as well as CDD/CDF
and other chlorinated pollutants. The commenter stated that it is
achievable for HMIWI to remove chlorinated plastics from the waste
stream that they burn. The commenter said that EPA can gather data that
will quantify the total amount of HCl that is attributable to the
combustion of chlorinated plastics and set a standard reflecting the
maximum degree of reduction that is achievable through the removal of
chlorinated plastics from the waste stream.
    The same commenter also recommended that EPA set beyond-the-floor
standards for metals based on removing all metals from the waste stream
before combustion, consistent with the requirements under Section
129(a)(2) and (3), which obligate EPA to require the maximum degree of
reduction in emissions that is achievable through the use of methods
and technologies before, during, and after combustion. The commenter
stated that metals do not belong in an incinerator because they cannot
be destroyed by incineration and are especially dangerous to public
health and deleterious to the environment. As far as the commenter
knew, EPA has never disagreed that removing metals from the HMIWI waste
stream is achievable technically and economically, and the commenter
noted that EPA has data from the MWC rulemaking that show materials
separation requirements are effective and cost-effective. (See Docket
A-89-08, various items.)
    Given the language of Section 129 that requires the maximum degree
of reduction in emissions that is achievable through the use of pre-
combustion measures, the commenter argued that EPA has a duty to gather
information on these measures and evaluate such measures in its beyond-
the-floor analysis. According to the commenter, EPA's failure to gather
information about the precise reduction of emissions that will result
from such measures and failure to provide any explanation for rejecting
such a standard is unlawful and arbitrary. The commenter noted that EPA
has committed to set final standards by September 2009, and stated that
EPA should not delay issuance of final standards to conduct this data
gathering, but should commence data gathering now and revise the HMIWI
regulations to include beyond-the-floor standards in the future.
    Response: As we explained in the 2008 re-proposal, the identified
beyond-the-floor add-on control measures we analyzed were not
reasonable on a cost-effectiveness basis, especially in light of the
significantly more stringent floor levels as compared to the 1997
rule's standards. We read the commenter's suggestion that we examine
additional beyond-floor measures but without delaying final action on
the re-proposal as recommending that we conduct the requested data
gathering and analysis for those measures in a subsequent rulemaking
action. A possible opportunity for that would be the next review of the
rule under Sections 129(a)(5) and (h)(3). In the interim,

however, we have decided to revise the waste management plan provisions
in Sec. Sec.  60.35e and 60.55c to promote the segregation of
chlorinated plastics and metals to the extent possible.
2. CO Emissions Limits
    Comment: One commenter argued that the proposed CO emissions limits
will be unattainable by many applicable units, based on the emissions
data provided in the docket. The commenter stated that the add-on
controls evaluated by EPA do not reduce CO emissions, and that CO
emissions can be a function of the feed material composition (which the
commenter stated EPA did not evaluate). As a result, the commenter
stated, HMIWI operators will have very little latitude or options to
meet the proposed CO limits. Three other commenters stated that
historical CO CEMS data from well-performing commercial HMIWI
demonstrate that the proposed CO emissions limit is not achievable on a
continuous basis and argued that the existing 40 ppmv emissions limit
must be retained. The commenters further stated that the proposed CO
standards must include a reasonable, extended averaging period (e.g.,
24 hours) that accounts for the variability of the waste stream and
waste characteristics. The commenters noted that the proposed standards
are currently based on discrete 3-hour average data developed during
performance test conditions, which they said do not account for the
typical operational variability. According to the commenters, such
snapshot data are also not representative of long-term continuous
monitoring, placing facilities with CO CEMS at a competitive
disadvantage with any revisions to the CO standard.
    The same three commenters also stated that the proposed CO standard
in combination with the 7 percent oxygen (O2) diluent
correction factor will pose technological monitoring challenges to
HMIWI that either choose or will be required to use CO CEMS, especially
given the variability of HMIWI operations and waste feed streams.
According to the commenters, costly monitoring systems (e.g., dual
range or ambient level monitors) will be needed, resulting in
additional QA activities. The commenters further stated that the
application of an O2 correction factor to the measured CO
concentration CEMS data may cause artificial exceedances of the CO
emissions standard at higher O2 operating scenarios.
    Response: Based on our review of CO emissions data for all HMIWI,
we have found many HMIWI outperforming the existing 40 ppmv CO limit.
We believe that the CO limits developed using the revised statistical
approach are more representative of actual operation, and we estimate
that a substantial percentage of HMIWI with their current controls will
still be capable of meeting the revised limits (89 percent of large, 76
percent of medium, and 100 percent of small/small rural HMIWI, on
average). Therefore, we disagree that the 40 ppmv CO limit must be
retained.
    Regarding the comment about the 3-hour average basis for the CO
limit, it should be noted that the 2008 re-proposal included an
amendment to Sec.  60.56c allowing sources using CEMS to demonstrate
compliance with the applicable emissions limit on a 24-hour block
average, instead of a 12-hour rolling average (as specified in the 1997
final rule). This amended provision should address concerns about the
ability of sources equipped with CEMS to demonstrate compliance with
emissions limits on a continuous basis (as opposed to a 3-hour annual
test) and would be consistent with past rulemakings for incineration
units (e.g., large and small MWCs).
    Regarding the comment about the application of an O2
correction factor to the CO CEMS data, it should be noted that
correction to consistent standards (e.g., percent O2) is
necessary in order to compare to other units and to an emissions limit.
Applying an O2 correction factor to CO CEMS should only be a
problem at O2 levels greater than 15 percent. For comparison
purposes, we reviewed the O2 levels recorded in initial test
reports, and found only about 7 of 57 HMIWI reported O2
levels above 15 percent during at least one pollutant test run, and we
estimate that 6 of those 7 with their current equipment will still meet
the revised CO emissions limits, based on a comparison of the revised
limits to the average CO concentrations for those HMIWI.
3. Opacity Limits
    Comment: Three commenters noted that EPA requested facility test
data from 2003 through 2006 for all pollutants except opacity, even
though annual opacity testing is required for all units. According to
the commenters, if EPA wanted to review and revise the opacity limit
pursuant to Section 129(a)(5), it should have requested opacity data
and should have used those data in the re-establishment of the MACT
standards. Instead, the commenters said, the proposed opacity limit was
inappropriately established from a single continuous opacity monitoring
system (COMS) located at a single HMIWI. The commenters argued that
data from a single unit are insufficient to set an emissions limit that
must be continuously achieved, and they said that EPA must seek
additional monitoring data. The commenters also noted that compliance
with the proposed opacity limit established by COMS is demonstrated
using a different measurement methodology (Method 9).
    The same three commenters, plus a fourth commenter, stated that the
methodology that EPA used to establish the 2 percent opacity limit
fails to account for actual opacity monitoring capabilities and normal
operational variability, such as that included in PS-1 (40 CFR part 60,
appendix B). According to the commenters, the inherent potential error
of a COMS meeting PS-1 could greatly exceed the proposed opacity limit
value. The fourth commenter argued that opacity under the worst
foreseeable circumstances for the best-performing units would thus
easily violate the MACT floor, which the commenter said would violate
Sierra Club. 167 F.3d at 665.
    All four commenters noted that, similar to COMS accuracy, Method 9
calls for recording visual observations to the nearest 5 percent at 15-
second intervals. The commenters stated that using a compliance method
with inherent potential accuracy levels exceeding the proposed 2
percent opacity limit appears problematic.
    Given the limitations of Method 9 and the variability of all the
HMIWI subject to the revised opacity standard, the first three
commenters recommended that EPA establish an opacity standard based on
Method 9 data instead of COMS data from a single unit. All four
commenters argued that the current 10 percent opacity limit is
reasonable, and would allow conventional compliance determination
methods to be used, accounting for their limitations.
    Response: The commenters' argument about how we established the
proposed opacity limit is somewhat misleading. While we acknowledge
that opacity data were inadvertently not included in the 2007-08 test
data request, we already had opacity data for nearly 90 percent of all
HMIWI from their initial compliance tests, and our initial opacity MACT
floor analysis was based on the best-performing 12 percent of sources
for opacity. As we stated in the preamble to the December 1, 2008 re-
proposal (73 FR 72983), based on the opacity averages alone, without
any accounting for variability, the MACT floor for opacity for existing
and new units would have been 0 percent. We tried to account for
variability by looking at the single highest opacity reading for HMIWI
in the MACT floor

for PM, based on opacity being an appropriate surrogate for PM. We
based our MACT floor opacity limit on the single highest COMS reading
(1.1 percent) for one of the HMIWI in the MACT floor for PM. Because we
commonly set opacity standards based on whole numbers and could not
round down without risking having the MACT floor unit not meet the
standard, we rounded up and proposed an opacity limit of 2 percent for
both new and existing HMIWI. However, we now believe this analysis was
incomplete. The analysis did not account for two other HMIWI in the
MACT floor for PM that could more effectively account for variability
for opacity. The maximum opacity averages for these two HMIWI are 5.87
and 4.17 percent. (See 2008 memorandum entitled ``Documentation of
HMIWI Test Data Database,'' which is included in the docket.) The
opacity data for these two HMIWI were measured using Method 9. Using
the same approach that we used at re-proposal, we are establishing an
opacity limit of 6 percent, by rounding up the highest opacity average
of 5.87 percent to the nearest whole number.
    Regarding the commenters' arguments that the inherent potential
error of a COMS meeting PS-1 could exceed the proposed opacity limits,
the potential error (about 4 percent opacity at the highest) is not the
same as expected error (more on the order of 0.5 percent). Nonetheless,
the increase in the opacity limit to 6 percent should address the
commenters' concerns on this issue.
    We disagree with the commenters' argument that a 10 percent opacity
limit be used to allow conventional compliance determination methods.
While opacity is read in 5 percent increments, average opacity can be
any number above 0. Method 9 values are averages of 24 readings, which
can include readings of 0 and an occasional 5 or 10 percent.
    Regarding the commenters' argument that only Method 9 data should
be used to establish the opacity standard because that is the
measurement method that would be used to demonstrate compliance, the
commenters' argument is moot, since the revised opacity standard is now
based on Method 9 results.
4. Percent Reduction Limits
    Comment: One commenter agreed with EPA's proposed elimination of
percent reduction alternatives. According to the commenter, EPA
correctly noted that standards based only on control technology
performance do not reflect the effects of non-technology factors and,
therefore, do not reflect the best units' actual performance.
Therefore, the commenter said, allowing units the option to meet these
percent reduction limits instead of emissions standards contravenes
Section 129, and EPA appropriately proposed to delete the percent
reduction limits.
    Three other commenters argued that the percent reduction compliance
option that was available in the 1997 rule and in the 2007 proposed
rule should be re-evaluated and retained for commercial HMIWI, since
the ability for such units to reduce emissions is due almost
exclusively to the effectiveness of the control equipment (and not
waste segregation). According to the commenters, commercial HMIWI
facilities, unlike captive units, cannot practically control the waste
that is put in the containers they process, and applicable regulations
from the U.S. Occupational Safety and Health Administration (OSHA)
preclude them from practicing waste segregation at the time of
treatment. Thus, the commenters noted, they experience extreme
variability during stack tests (especially for volatile metals Cd, Pb,
and Hg) and will experience higher inlet concentrations than captive
units; since they operate at the same control efficiency, they will
exhibit higher stack emissions. The commenters stated that the percent
reduction option is a better assessment of the performance of the
control system for commercial units.
    Response: We have decided not to include percent reduction limits
in the final rule. In addition to the reasons we provided in the re-
proposal, while commercial HMIWI facilities face greater challenges in
controlling the waste they receive, compared to ``captive'' units, they
are nonetheless capable of taking steps to educate their customers
(i.e., waste generators) regarding waste segregation and should also
have some control based on the waste management plans, contract
requirements, and waste acceptance protocols they negotiate with their
customers. Consequently, non-technology factors are under their control
to a limited extent, which does not support their rationale for a
percent reduction limit. The effect of raw material inputs on emissions
from HMIWI could instead be downplayed by a percent reduction limit
that allows more emissions provided a given level of removal
efficiency.
5. PCB and POM Emissions Limits
    Comment: One commenter noted that EPA has interpreted the CAA as
allowing the Agency to meet the requirements of Section 112(c)(6) by
setting standards for incinerator emissions of 112(c)(6) pollutants
under Section 129. According to the commenter, EPA has acknowledged
that HMIWI account for a large portion of the aggregate emissions of
both PCBs and POM. Thus, to satisfy Section 112(c)(6), the commenter
argued that EPA must use its authority under Section 129(a)(4) to set
emissions standards for both of these pollutants. Noting EPA's argument
that its standards for CDD/CDF and Hg ``effectively reduce'' emissions
of PCBs and POM and thus satisfy Section 112(c)(6), the commenter said
that Section 112(c)(6) requires that these HAP be subject to MACT
standards. Because the best performing units used to set these
standards may be achieving reductions in PCBs and POM by means other
than just controlling CDD/CDF and Hg emissions--e.g., by ensuring that
no PCB-containing wastes are put in the incinerator or by not
incinerating chlorinated plastics--the commenter argued that EPA's
standards for CDD/CDF and Hg do not constitute lawful MACT standards
for PCBs and POM and, therefore, do not satisfy Section 112(c)(6).
    Response: For the reasons we set forth in the 2008 re-proposal (see
73 FR at 72991-92) and in the preamble for today's rule (see section
VII), we continue to take the view that while the rule does not
identify specific limits for POM and PCB, emissions of those pollutants
are nonetheless ``subject to regulation'' for purposes of Section
112(c)(6). While we have not identified specific numerical limits for
POM and PCB, we believe CO serves as an effective surrogate for those
pollutants, because CO, like POM and PCBs, is formed as a byproduct of
combustion. We believe that dioxins/furans also serve as an effective
surrogate for PCBs, because the compounds act similarly and, thus, are
expected to be controlled similarly using HMIWI emissions control
technology--e.g., wet scrubbers or fabric filters (with or without
activated carbon). Furthermore, recent HMIWI emissions test data for
PCBs and dioxins/furans show that HMIWI well-controlled for dioxins/
furans also achieve low PCB emissions. (See 2008 memorandum entitled
``Documentation of HMIWI Test Data Database,'' which is included in the
docket.) It should also be noted that PCBs are generally found in
higher concentrations than dioxins/furans (also the case for HMIWI), so
HMIWI equipped with the aforementioned emissions controls would be even
more effective at reducing PCB emissions. Consequently, we have
concluded that the emissions

limits for CO function as a surrogate for control of both POM and PCBs,
and the limits for dioxins/furans function as a surrogate for PCBs,
such that it is not necessary to promulgate numerical emissions limits
for POM and PCBs with respect to HMIWI to satisfy CAA Section
112(c)(6).
    To further address POM and PCB emissions, the final rule also
includes revised waste management plan provisions in Sec. Sec.  60.35e
and 60.55c that encourage segregation of the types of wastes that lead
to these emissions, such as chlorinated plastics and PCB-containing
wastes.

E. Monitoring

    Comment: One commenter argued that the monitoring requirements in
the HMIWI regulations are inadequate because they do not provide for
emissions monitoring as required by Section 129. According to the
commenter, EPA's exclusive reliance on parameter monitoring for most
pollutants and units is unlawful. The commenter stated that EPA must
require all HMIWI to use the available CEMS (e.g., HCl, Hg, metals,
CDD/CDF) to monitor their emissions. The commenter indicated that CEMS
are the only requirements that can possibly provide data adequate to
ensure compliance with emissions standards and protection of public
health and the environment, consistent with Section 129(c)(1).
    Two other commenters argued that continuous monitoring of CO with a
24-hour block average should be required of all existing incinerators
to assure efficient combustion. However, the two commenters stated that
continuous air monitoring of metals and other toxics should not be
adopted as an alternative to stack testing until CEMS accuracy and
reliability has been fully verified by EPA.
    Response: The CAA provides us with broad discretion to establish
monitoring requirements as necessary to assure compliance with
applicable requirements. As we noted in the preamble to the 1997 final
rule (62 FR 48360), the most direct means of ensuring compliance with
emissions limits is the use of CEMS. As a matter of policy, the first
and foremost option considered by EPA is to require the use of CEMS to
demonstrate continuous compliance with specific emissions limits. Other
options are considered only when CEMS are not technically available or
when the impacts of including such requirements are considered
unreasonable (due to high costs, for example). When monitoring options
other than CEMS are considered, there is always a tradeoff between the
cost of the monitoring requirement and the quality of the information
collected with respect to determining actual emissions. While
monitoring of operations (operating parameters) cannot provide a direct
measurement of emissions, it is usually much less expensive than CEMS,
and the information provided can be used to ensure that the incinerator
and associated air pollution control equipment are operating properly.
This information provides EPA and the public with assurance that the
reductions envisioned by the regulations are being achieved. (62 FR
48360-1)
    For the 1997 final rule, we developed testing and monitoring costs
for a range of options. (See Legacy Docket ID No. A-91-61, item IV-B-
66.) At that time, we concluded that the cost of CEMS were unreasonably
high relative to the cost of the incinerators and emissions controls
needed for compliance. (62 FR 48360-1.) For today's final rule, we also
compared the costs of CEMS for various pollutants to the costs of the
incinerators, emissions controls, and parameter monitors, and reached
the same conclusion as we reached before. (For further information, see
2009 memoranda entitled ``Revised Baseline Operating Costs for Existing
HMIWI'' and ``Revised Compliance Costs and Economic Inputs for Existing
HMIWI,'' which are included in the docket for today's rulemaking.)
Table 3 of this preamble presents the annual costs for CEMS, parameter
monitoring systems, emissions controls, and incinerators, based on
model unit cost calculations for all four HMIWI size categories.

       Table 3--Comparison of Annual Costs for CEMS, Parameter Monitoring Systems, and Emissions Controls
----------------------------------------------------------------------------------------------------------------
                                                     Parameter monitoring       Emissions
           Pollutant                    CEMS                systems              controls         Incinerators
----------------------------------------------------------------------------------------------------------------
CO.............................  CO CEMS: $149,300  Combustion control      Secondary chamber  Incinerator:
                                  per year (yr).     (charge rate,           retrofit:          $54,800-$366,000/
                                                     secondary chamber       $15,100-$80,800/   yr.
                                                     temperature): $6,000-   yr.
                                                     $9,900/yr.
HCl............................  HCl CEMS:          Packed-bed scrubber     Packed-bed
                                  $171,400/yr.       (flue gas               scrubber:
                                                     temperature, scrubber   $51,600-$104,000/
                                                     liquor flow rate and    yr.
                                                     pH): $5,200/yr.
PM.............................  PM CEMS: $195,200/ Fabric filter (fabric   Fabric filter:
                                  yr.                filter inlet            $130,000-$268,00
                                                     temperature): $4,200/   0/yr.
                                                     yr.
Metals.........................  Multi-metals
                                  CEMS: $57,800/yr.
Hg.............................  Hg CEMS: $313,900/ Activated carbon        Activated carbon
                                  yr.                injection system        injection
                                                     (activated carbon       system: $5,400-
                                                     injection rate):        $56,300/yr.
                                                     $4,800/yr.
CDD/CDF........................  Sorbent trap
                                  biweekly
                                  monitoring:
                                  $37,900/yr.
----------------------------------------------------------------------------------------------------------------

    Regarding the comment that CEMS for metals and other toxics should
not be adopted until their accuracy and reliability has been fully
verified, the re-proposal specified that the CEMS options would be
available to a facility only when a final performance specification has
been published in the Federal Register or when a site-specific
monitoring plan has been approved. This should address the commenters'
concerns.

F. Emissions Testing

    Comment: One commenter appreciated EPA's efforts to improve
performance testing requirements and supported the proposed changes. A
second commenter objected to the provisions of Sec.  60.37e(f) allowing

submission of previous stack tests to show compliance with proposed
emissions standards for existing HMIWI, arguing that most of the stack
tests were conducted over 7 years ago, and are also not statistically
reliable because so few tests were conducted. The commenter stated that
the provisions disregard the attention that Section 129 expected EPA to
place on solid waste incinerators.
    The second commenter also objected to the proposed one-time test
requirement for Pb, Cd, Hg, and CDD/CDF, arguing that a single test
result does not provide adequate assurance that the emissions standards
have been met or are continuously being achieved by operations
combusting a non-homogeneous waste stream. According to the commenter,
allowing a one-time test also provides a strong disincentive to
installing CEMS on HMIWI. The commenter noted that if EPA still wants
to reduce testing requirements, it could provide skip testing
provisions for these pollutants similar to existing provisions in Sec.
60.56c(c)(2), especially in future rulemaking, once the industry has
demonstrated sustained compliance.
    Response: Regarding the comment objecting to the submission of
previous stack tests to show compliance with new emissions standards
for existing HMIWI, we attempted to address such concerns in Sec.
60.37e(f)(2) and (3), specifying that the HMIWI had to be operated in a
manner expected to result in the same or lower emissions, that it could
not have been modified such that emissions would be expected to exceed
the previous test results, and that emissions test results prior to the
year of the 1996 proposal could not be accepted. We believe that these
provisions are adequate to ensure an accurate and reliable result.
Furthermore, based on the language in the re-proposal, it is unlikely
that any commenter could have anticipated a change in the base year
(1996) for emissions tests that would be accepted to demonstrate
compliance with the revised emissions limits in the final rule, such
that the commenter would have had a meaningful opportunity to comment
on the issue.
    Regarding the comment objecting to the one-time test requirement
for metals and CDD/CDF, the annual tests are intended to be surrogates
for combustion, particulate, and acid gas control, supplementing
existing continuous monitoring requirements. We believe that the annual
tests for combustion and particulate control and the continuous
emissions monitoring of activated carbon injection are sufficient to
ensure compliance with the metals and CDD/CDF emissions limits.
However, if the State implementing the HMIWI regulations for existing
units in its jurisdiction believes that more frequent metals and CDD/
CDF testing is a necessary requirement for those units, they have the
option to prepare State plans for EPA review that include those
requirements, or to simply require a particular source to conduct such
testing. Section 116 of the CAA preserves a State's authority to
regulate more stringently under Section 111. Given the more stringent
requirements in the HMIWI rule (relative to the 1997 rule) being
promulgated today, we do not want to impose additional testing
requirements that are not necessary to assure compliance with the
requirements of this final rule. Also, we did not provide an
opportunity to comment on such additional emissions testing in the
December 2008 re-proposal, and we would want to develop a fuller record
on any such requirements and provide an opportunity to comment on those
requirements before imposing them in a final rule. However, we would be
willing to consider such a change at the next technology review, if
such a change is necessary to reliably demonstrate compliance.

G. Alternatives to On-Site Incineration

    Comment: Five commenters supported alternatives to on-site
incineration, such as autoclaving. One of the commenters stated that 90
percent or more of medical waste could be safely diverted from
incineration. The commenter further noted that alternative treatment
technologies like autoclaves and microwaves work, are available, and
are approved by regulatory agencies. The commenter argued that these
technologies provide a much healthier alternative to incineration.
Another of the commenters suggested EPA supplement its proposed rule to
specify a phase-in requirement that diverts all medical waste not
required by law or regulation to be incinerated to go to approved
alternative non-incineration disposal methods; the commenter also
recommended that EPA prohibit autoclave residues from being
incinerated. Three of the commenters stated that EPA should initiate a
ban on incineration of medical waste, and in the interim give
incentives to industries using safer, cleaner alternatives to
incinerating medical waste, such as autoclaving and microwaving.
    Five other commenters noted the disadvantages associated with
incineration alternatives such as autoclaving. One of the commenters
noted that EPA's supporting documents for the proposed rule seem to
endorse such alternatives but fail to recognize that some facilities
generate waste types for which autoclaving and landfilling is not
adequate treatment. As examples, another of the commenters noted that
numerous research facilities insist that all of their waste be
incinerated, and three of the commenters noted that most States and
many local governments have imposed requirements on the disposal of
these types of wastes and identified incineration as an authorized
means of disposal; further, some States expressly require incineration
of pathological wastes and/or prohibit autoclaving or landfilling of
such wastes. With the proposed emissions limits, the same three
commenters expected that HMI waste incineration capacity will
disappear, and captive units will be limited by permit from accepting
wastes from off-site; as a result, the commenters concluded, some waste
generators will be left with a State requirement to incinerate waste,
with little or no available HMIWI treatment options and capacity. One
commenter noted that that sterilized waste is often transferred to
regional MWC facilities for incineration, especially in their
metropolitan area, and noted that MWC emissions limits are less
stringent than the current and proposed limits for HMIWI. Thus, the
commenter concluded, if the HMIWI regulation increases autoclaving and
reduces use of their facility, it will have a significant adverse
effect on air quality.
    One of the commenters stated that EPA's studies for the proposed
rule also fail to recognize the environmental impacts of transporting
autoclaved medical wastes to regional landfills, such as depletion of
landfill space, landfill gas emissions, landfill leachate issues, and
impacts of waste transportation traffic. Another commenter noted that
autoclaving does not achieve the 90 percent volume reduction that can
be achieved with incineration and, with many landfills at or
approaching capacity, volume reduction prior to landfilling is a much
preferred option.
    One commenter also noted that steam sterilization can result in the
release of uncontrolled Hg vapors from the autoclaving process, so any
medical waste displaced from their facility to autoclaves would result
in an increase in Hg emissions from the autoclaves or the MWC. The
commenter said that these potential impacts need to be assessed before
any standard is adopted.
    Response: Section 129 of the CAA provides EPA with the authority to
establish emissions limits for the nine specified pollutants (HCl, CO,
Pb, Cd,

Hg, PM, CDD/CDF, NOX, and SO2). Today's action
satisfies EPA's obligation to respond to the Court's remand of the 1997
MACT floor determinations, as well as EPA's duty to conduct its first
periodic review of the standards and requirements of the HMIWI rule.
While a record that supported complete elimination of emissions of the
enumerated pollutants is theoretically possible, the record for today's
rule does not show that such an outright ``ban'' of incineration is
required to meet EPA's obligations.
    We agree with the commenters that it is appropriate to address the
disadvantages and environmental impacts associated with incineration
alternatives such as autoclaving in background documentation for the
HMIWI rule, even though the revised standards in today's rule are
floor-based (for which we cannot consider costs) rather than beyond-
the-floor-based (where costs are to be considered). We also agree that
incineration is sometimes insisted upon or even required by some
research facilities and State and local governments, and we have
incorporated those comments into the revised background documentation
for the final rule.
    Regarding the comment that some metropolitan areas require
autoclaved waste to be sent to MWC units, while the commenter is
correct that MWC limits are currently higher than the 1997 promulgated
HMIWI limits and the 2008 re-proposed HMIWI limits, the MWC standards
are on remand to the Agency, and EPA will be reviewing those standards.
At this juncture, we cannot predict the outcome of that remand
response.
    Comment: One commenter stated that EPA's studies for the proposed
rule fail to recognize and consider all the risks to the public
associated with closing captive HMIWI and transporting medical/
infectious wastes to large commercial incinerators, especially in
regions such as the western U.S., where such commercial incinerators
are not well distributed.
    Response: We believe that the revised emissions limits are more
representative of actual operation at HMIWI and will impact fewer HMIWI
than the December 2008 re-proposal, which should address the
commenter's concerns. Moreover, in this technology- and MACT floor-
based rulemaking, we do not believe that we could permissibly adopt
standards that are less stringent than the floor based on
considerations of risk. See Sierra Club v. EPA, 353 F.3d 976 (DC Cir.
2009).

H. Medical Waste Segregation

    Comment: Contrary to what EPA stated in its summary of waste
segregation survey responses, two commenters argued that there is ample
evidence that the extent to which waste segregation is conducted by our
healthcare facilities is far from optimal, and that further waste
segregation could easily occur. Multiple commenters recommended that
EPA supplement the proposed rule to minimize or eliminate the inclusion
of plastic wastes (a chief contributor to dioxin formation), Hg (e.g.,
Hg-containing dental waste, Hg-containing devices), and other hazardous
wastes in the waste sent to incineration; end the burning of
confidential documents (e.g., medical records) and other paper products
that could be shredded and recycled; and require waste management plans
from all generators of medical waste that use incineration as a
disposal option. As examples, one of the commenters said captive HMIWI
could be required to train staff to minimize inclusion of Hg-containing
devices and other heavy metals from the waste stream; and commercial
HMIWI could be required to provide educational materials to encourage
customers to prevent inappropriate disposal of metals-containing
devices and other items into wastes supplied to the commercial HMIWI.
Another commenter supported the idea of enhancing waste management
practices at the point of generation and noted that their commercial
facility offers training sessions with hospitals and institutions on
the importance of separating items containing Hg and other hazardous
substances from the rest of their medical waste and has implemented and
manages recycling programs for paper, bottles, glass, cardboard,
metals, construction material, and sharps containers.
    To ensure effective waste segregation by commercial facilities, one
of the commenters further recommended that EPA revise the regulation to
state that incinerator operators are responsible for all of the waste
in their possession and the emissions that result, and should clarify
for all incinerator operators that the term ``affected source'' in
Sec.  60.55c refers to them.
    Four commenters noted that the proposed new rule for emissions from
HMIWI does not address pharmaceutical drugs, nor does it address how
hazardous pharmaceuticals are segregated from non-hazardous. The
commenters stated that not all incinerators, such as those in North
Carolina, are licensed to burn pharmaceuticals classified as hazardous.
The commenters recommended that EPA require each State to develop and
implement programs to ensure that hazardous and non-hazardous
pharmaceuticals are being segregated.
    Response: While EPA's authority to set emissions standards under
Section 129(a)(2) reaches only incinerators of solid waste and does not
directly extend to generators of waste who are not owners and operators
of solid waste incineration units, we are amending the waste management
plan provisions in the final rule to promote greater waste segregation
(e.g., plastics, metals, PCB-containing wastes, pharmaceuticals). Given
the OSHA requirements to which commercial HMIWI operators are subject,
those operators cannot be expected to remove certain materials from the
waste they receive, but they can be expected to train and educate their
clients to conduct their own waste segregation, especially with regard
to the materials listed above. We are including language to that effect
in the waste management provisions of the final rule.

I. Startup, Shutdown, and Malfunction

    Comment: Three commenters argued that EPA should apply to the HMIWI
rule the decision issued by the U.S. Court of Appeals for the DC
Circuit (Sierra Club v. EPA, 551 F.3d 1019 (DC Cir. 2008)), which
vacated the SSM exemptions in EPA's General Provisions implementing
Section 112 on the grounds that the exemptions violate the CAA's
requirement that some Section 112 standards apply continuously. The
commenters stated that the reasoning provided by the court in its
decision also applies to the HMIWI rule.
    According to one of the three commenters, the CAA makes clear that
EPA may not exempt sources from compliance with Section 129 emissions
standards during SSM events and that the current exemptions (found in
Sec. Sec.  60.56c(a) and 60.37e(a)) are unlawful. The commenter noted
that EPA restricted the current SSM exemption to periods when no
hospital or medical/infectious waste is being charged to HMIWI.
However, the commenter said this does not bring EPA's regulations into
compliance with the CAA or suffice to protect the public from toxic
emissions during periods of SSM, because HMIWI could stop charging HMI
waste during an SSM event but still emit toxic pollution through a
bypass valve directly to the environment. To the extent EPA is not
soliciting comment on the SSM exemption as part of its response to the
remand in Sierra Club v. EPA, 167 F.3d

658 (DC Cir. 1999) or its review of regulations under Section
129(a)(5), the commenter petitioned it to do so under the authorities
in Kennecott Utah Copper Corp. v. Department of Interior, 88 F.3d 1191
(DC Cir. 1996).
    A fourth commenter argued that if the SSM court decision is upheld,
this would substantially impact the approach for establishing ``worst
reasonable foreseeable circumstances'' and the approach for
establishing emissions limits based on available data. According to the
commenter, emissions and controllability during periods of SSM are
different than ``normal operation,'' and the commenter noted that EPA
currently sets limits by reviewing data taken during ``normal
operation,'' since no one generally conducts stack tests during SSM.
    One commenter requested that emissions from SSM events be included
in the calculations of a facility's potential to emit, which in turn
determines the applicability of some Federal requirements. The
commenter also recommended that emissions from SSM events should be
included in modeling to ensure that new or expanded sources do not
cause ambient air quality to exceed health-based levels. In lieu of
modeling, the commenter said there should be actual monitoring of SSM
events to accurately determine the individual types of toxic air
pollutants and amounts of toxic air pollutant releases. The commenter
recommended that there be mandatory penalties for SSM events based on
the amounts and toxicity of the emissions. To illustrate the point, the
commenter included documentation about bypass events at a local HMIWI.
Two additional commenters also requested that EPA conduct modeling to
assess the types and amounts of pollutants released during bypass
events and take appropriate steps to regulate these ``fugitive''
emissions. All three commenters recommended that pollution control
equipment be required for bypass events, whether the event is operator
error or violation.
    Another commenter recommended that EPA revise the General
Provisions or the specific standards to subject SSM periods to
appropriate work practice standards, including procedures to minimize
emissions during those periods, rather than establish MACT emissions
limits that are impossible to meet during SSM. According to the
commenter, CAA Section 112(h) allows the Administrator to promulgate a
design, equipment, work practice, or operational standard, or
combination thereof, in lieu of an emissions standard where it is not
feasible to prescribe or enforce an emissions standard. The commenter
said that emissions measurement is not practicable during SSM periods.
    Response: While the Court's ruling in Sierra Club v. EPA, 551 F.3d
1019 (DC Cir. 2008), directly affects only the subset of CAA Section
112(d) rules that incorporate Sec.  63.6(f)(1) and (h)(1) by reference
and that contain no other regulatory text exempting or excusing
compliance during SSM events, the legality of source category-specific
SSM provisions such as those adopted in the 1997 HMIWI rule is
questionable.
    To our knowledge, no HMIWI facilities have ever done any testing
during an SSM event, except perhaps the few that have CO CEMS (although
under the definition of ``malfunction'' in Sec.  60.51c, operators are
directed to monitor all applicable operating parameters during
malfunctions until all waste had been combusted or until the
malfunction ceases, whichever comes first). It would be very difficult
to do any meaningful testing during such an event because the exhaust
flow rates, temperatures, and other stack conditions would be highly
variable and could foul up the isokinetic emissions test methods (thus
invalidating the testing).
    The 1997 rule excused exceedance of emissions standards during SSM
events only in instances where ``no hospital waste or medical/
infectious waste is charged to the affected facility.'' 40 CFR
60.56c(a). This means that in any SSM periods where such waste is being
charged and an exceedance of the standards occurs, the source is in
violation of the requirements of the standards. Based on the 1997 HMIWI
rule's definitions of the terms ``startup'' and ``shutdown,'' no waste
should be combusted during these periods, so emissions should be low
during them--essentially the emissions from burning natural gas. Under
Sec.  60.51c, startup is defined as the period of time between the
activation of the system and the first charge to the unit. For batch
HMIWI, startup means the period of time between activation of the
system and ignition of the waste. Shutdown is defined as the period of
time after all waste has been combusted in the primary chamber.
Shutdown must start no less than 2 hours after the last charge to the
incinerator for continuous HMIWI, and no less than 4 hours for
intermittent HMIWI. For batch HMIWI, shutdown must commence no less
than 5 hours after the high-air phase of combustion has been completed.
Consequently, it should not be possible for HMIWI to exceed the
applicable emissions limits during startup and shutdown periods. This
suggests that the exemption from standards during startup and shutdown
is of virtually no utility to HMIWI, such that there is any need for
EPA to retain the exemption in today's final rule.
    Malfunctions present a similar situation in terms of how the 1997
rule functioned, if a slightly different situation factually. Again,
the SSM exemption of Sec.  60.56c(a) applied only where no hospital
waste and no medical/infectious waste was being charged. Under
Sec. Sec.  60.56c(a) and 60.37e(a) of the HMIWI rules, facilities are
required to stop charging waste as soon as a malfunction is identified
and not charge any additional waste. ``Malfunction'' is defined in
Sec.  60.51c as any sudden, infrequent and not reasonably preventable
failure of air pollution control equipment, process equipment, or a
process to operate in a normal or usual manner, but does not include
failures caused, in part, by poor maintenance or careless operation.
During malfunction periods, operators must operate within established
parameters as much as possible and continue to monitor all applicable
operating parameters. So, there should be low emissions during such
periods, but how low is not known. In any case, the rule as promulgated
in 1997 did not excuse exceedances of emissions standards during
malfunctions if hospital waste or medical/infectious waste was being
charged during the malfunction. Moreover, our final standards
established today are based on the best data available to the Agency,
and we have no data to support modifying the floors for malfunction
periods.
    While EPA is still in the relatively early process of formulating
its strategy for addressing the SSM court decision and the numerous
Section 112 and 129 rules that contain varying provisions regarding SSM
events, we are revising the HMIWI rules in today's final rulemaking to
delete the 1997 rule's narrow exemption from emissions limits during
periods of SSM. As explained above, the exemption and definitions as
promulgated in 1997 provided virtually no utility, and we, therefore,
expect that today's deletion of the SSM exemption will have very
little, if any, impact on HMIWI units' compliance status. In the event
that sources, despite their best efforts, fail to comply with
applicable standards during SSM events (as defined by the rule), EPA
will determine an appropriate response based on, among other things,
the good faith efforts of the source to minimize emissions during SSM
periods, including preventative and corrective

actions, as well as root cause analyses to ascertain and rectify excess
emissions. This approach is consistent with that discussed in a recent
letter by Adam M. Kushner, Director, Office of Civil Enforcement, to
counsel representing various industry associations, entitled ``Re:
Vacatur of Startup, Shutdown, and Malfunction (SSM) Exemption (40 CFR
sections 63.6(f)(1) and 63.6(h)(1))'' (July 22, 2009) (included in the
docket for today's rulemaking).
    For the reasons discussed above, we disagree with the commenter who
claimed that, in the context of this rulemaking, removal of the SSM
exemption would substantially impact the MACT floor approach. Deletion
of the exemption should have no impact on the use and analysis of the
MACT compliance data upon which the revised standards are based in this
rule. This is because the 1997 rule's exemption provisions already had
a very limited focus, in excusing compliance with standards only when
HMI waste was not being charged to the incinerator; even under the 1997
rules, if HMI waste was being charged during an SSM event, the
standards continued to apply. Moreover, the commenter provided no
information to support its position. Therefore, it is similarly
unnecessary to accept other commenters' recommendations to specify
mandatory penalties during SSM events or impose unique pollution
controls for bypass events--these concerns should be adequately
addressed by today's removal of the SSM exemption, which includes
removal of the 1997 rule's exemption during SSM periods to the
prohibition of using a bypass stack.
    We also disagree that it is necessary to revise the CAA Section 112
General Provisions of 40 CFR part 63 to impose work practice
requirements that apply in lieu of numeric emissions standards during
SSM periods, in the context of this CAA Section 129 rulemaking. The
commenter who suggested this approach cited CAA Section 112(h) as the
basis of authority for such a change, but neither that section of the
Act nor the part 63 General Provisions apply to standards promulgated
under Section 129, which by its terms requires numeric emissions
standards for the pollutants specified in Section 129(a)(4).

J. Economic Impacts

    Comment: Two commenters argued that the proposed limits are
unattainable without significant financial investment, which they said
will ultimately be passed on to an already overburdened healthcare
system. The commenters urged EPA to reconsider the proposed rule. One
of the commenters suggested EPA keep emissions limits for existing
HMIWI at current levels.
    A third commenter argued that this sort of rule could also have
severe adverse consequences on other industries, as well as the
economy, energy and natural resources, and environment. A fourth
commenter stated that the level of source shutdowns that has occurred
in the HMIWI industry should not be allowed to occur in other Section
112 or 129 source categories, as it would severely cripple the
manufacturing base of this country. The commenter urged EPA to consider
costs and other impacts when developing rules, as required under
Section 129. According to the commenter, the current financial crisis
demonstrates the tremendous impact on jobs and the broader economy due
to increased operational costs and facility shutdowns.
    Response: We estimate that the revised limits for the final rule
will be viewed as more attainable than were the 2008 re-proposed
standards, and will result in less burdensome economic impacts for the
industry. (See 2009 memorandum ``Revised MACT Floors, Data Variability
Analysis, and Emission Limits for Existing and New HMIWI'' and 2009
report ``Economic Impacts of Revised MACT Standards for Hospital/
Medical/Infectious Waste Incinerators,'' which are included in the
docket for today's rulemaking.) It should be noted that other rules do
not necessarily have to take the same MACT floor approach as that taken
in this rule (every industry, every situation is different), so the
argument that promulgation of this rule as proposed would adversely
affect other regulated industries is not a given. It should also be
noted that under Section 129 we cannot consider costs and other impacts
when we are establishing MACT floor requirements.
    Comment: One commenter disagreed with EPA's estimation of economic
impacts, especially as it affects their facility. The commenter
specifically questioned EPA description of HMIWI demand as being
extremely price insensitive (i.e., that the price charged has little
effect on the quantity of medical waste incinerated and can be passed
on to customers in full). Based on their years of experience in selling
services, the commenter indicated that the demand for medical waste
incineration at their facility is a curve reflecting the interplay of
different customer groups, rather than a steep curve as presented in
EPA's analysis (details provided in public comment). Based on a
graphical depiction of their facility's fixed costs, variable costs,
and total costs overlaid with the demand structure, the commenter
stated that their facility makes only a modest profit and could not
operate at any level of volume profitably if the costs of complying
with the new regulations are added to the current cost structure
(graphical depiction provided in public comment).
    The commenter recommended that the economic analysis be revised to
reflect the realistic economic impacts on their company. The commenter
noted that EPA's estimate of their gross sales ($12 million) is greater
than they have averaged in recent years, qualifying them as a small
business. The commenter also noted that there are no data or analysis
to justify EPA's estimate of their company's profits (greater than $30
million) after adoption of the proposed regulations. According to the
commenter, they will in fact be forced out of business.
    Three other commenters noted that the economic analysis does not
mention the restrictions imposed by State and local governments in
resorting to alternative waste treatment methods.
    Response: The demand curve we used in our economic analysis was
meant to apply to the industry as a whole, and, as such, some
assumptions and simplifications were necessary. Nonetheless, we have
reviewed the commenter's concerns in revising our economic analysis for
the final rule. We acknowledge the mistakes in our previous economic
analysis regarding the commenter's profits and sales and have addressed
them in our revised economic analysis. We have also addressed the
restrictions noted by the other three commenters in the revised
analysis. Finally, it should be noted that the revisions to the
emissions limits for the final rule should mitigate the economic
impacts described here.
    Comment: One commenter stated that, although their company is a
small entity, they were not given the opportunity to participate in the
development of the proposed HMIWI rule, as provided under the Small
Business Regulatory Enforcement Fairness Act (SBREFA). According to the
commenter, EPA did not conduct the appropriate analysis and incorrectly
assumed that their business had annual revenue exceeding the Small
Business Size Standards. The commenter provided tax returns documenting
their status as a small entity.
    Response: We properly accounted for the impacts of the re-proposed
rule in 2008 based on our analysis of the data we then had. The base
year data we

were using in our economic analysis (2007) showed sales numbers that
indicated they were not a small business. After receiving public
comments and additional information, we have accounted for any recent
changes in small entity status and re-analyzed the economic impacts of
the rule on small entities. (See 2009 report ``Economic Impacts of
Revised MACT Standards for Hospital/Medical/Infectious Waste
Incinerators,'' which is included in the docket for today's
rulemaking.) Because we are beyond proposal, we cannot convene a pre-
proposal SBREFA panel. After considering the economic impacts of this
final rule on small entities, we can certify that today's final rule
will not have a significant economic impact on a substantial number of
small entities. The one small entity directly regulated by today's
final rule is a small business that owns two HMIWI. We have determined
that this one small entity may experience an impact of approximately
$3.15 million per year to comply with the final rule, resulting in a
cost-to-sales ratio of approximately 45 percent. The small entity is a
company in Maryland, which owns and operates a commercial facility at
that location. There are only nine other commercial facilities, which
are owned and operated by other companies, and the closest are in North
Carolina and Ohio. Therefore, the entity is a regional monopolist and
is able to raise the price by more than the per unit cost increase. We
expect there to be a reduction in the amount of its services demanded
due to the price change. Because of closures of captive HMIWI, there
may also be an increase in the demand for its services that may reduce
the decrease in revenues associated with the price increase.
    Two other entities are defined as borderline small: Their parent
company sales or employment in 2008 are above the SBA size-cutoff for
small entities in their North American Industry Classification System
(NAICS) codes, but are near enough to the size cut-off that variations
in sales or employment over time might move them below the small
business criterion. Based on 2008 sales data for these two entities,
the cost-to-sales ratio is less than 1 percent for one entity and 1.4
percent for the other. It should be noted that the entity with the
higher cost-to-sales ratio (1.4 percent) is a commercial unit and would
have the ability to pass the cost along to their customers and would be
expected to be able to afford compliance. Therefore, neither entity is
likely to incur significant impacts. (See 2009 memorandum entitled
``Updated Sales Information for Companies Considered Borderline Small
Entities,'' which is included in the docket for today's rulemaking.)
    Although today's final rule will not have a significant economic
impact on a substantial number of small entities, we nonetheless have
tried to reduce the impact of this rule on small entities, to the
extent allowed under this CAA MACT floor rulemaking. For each
subcategory of HMIWI, we are promulgating emissions limits that are
based on the MACT floor level of control, which is the minimum level of
stringency that can be considered in establishing MACT standards. Under
the CAA and the case law, EPA can set standards no less stringent than
the MACT floor and, therefore, we were unable to eliminate the impact
of the emissions limits on the small entity that would be regulated by
the final rule. We nevertheless worked to minimize the costs of testing
and monitoring requirements to the extent possible under the statute,
in light of our final impacts analysis.

V. Impacts of the Final Action for Existing Units

    Over the last three years, about 25 percent (19 of 76 units) of the
existing HMIWI have ceased operation. This trend is not surprising, and
supports EPA's analysis, which shows that even in the absence of
increased regulatory requirements, less expensive alternative waste
disposal options are available for almost all facilities that operate
HMIWI. Therefore, EPA expects this trend of unit closures to continue
even in the absence of the regulatory changes. The additional costs
imposed by this action are likely to accelerate the trend towards
alternative waste disposal options. Our analysis suggests that sources
are likely to respond to the increased regulatory requirements by
choosing to minimize the current cost of on-site incineration (e.g.,
improve waste segregation), use alternative waste disposal options, or
send the waste to an off-site commercial incinerator.
    The EPA's objective is not to discourage continued use of HMIWI;
EPA's objective is to adopt EG for existing HMIWI that fulfill the
requirements of CAA Section 129. In doing so, the primary outcome
associated with adoption of these EG may be an increase in the use of
alternative waste disposal and a decrease in the use of HMIWI.
Consequently, EPA's impact analyses of the final rule include complete
analyses of two potential scenarios. The first scenario, which will be
referred to as the ``MACT compliance'' option for the remainder of this
preamble, assumes that all units continue operation and take the
necessary steps to achieve compliance. The second scenario, which will
be referred to as the ``alternative disposal'' option for the remainder
of this preamble, assumes that all facilities choose to discontinue
operation of their HMIWI in favor of an alternative waste disposal
option. While several different disposal options, such as sending waste
to a municipal waste combustor or commercial HMIWI or using chemical
treatment (e.g., ozone, electropyrolysis, chlorine compounds, alkali
agents), thermal treatment (e.g., plasma arc, microwave technologies),
or mechanical systems (e.g., shredding, compacting) may be available to
some facilities, EPA assessed the impacts of another alternative waste
disposal option. This option involves on-site sterilization of the
waste using an autoclave followed by landfilling of the sterilized
waste. EPA selected the autoclave/landfilling option because it is a
widely available and highly used alternative. The results of both the
MACT compliance and autoclave/landfilling options are provided in the
discussion of impacts. While the likely outcome of the rule revisions
is somewhere in between the two options that EPA selected for analysis
(some units will comply with the standards and some will discontinue
operations), EPA's analyses provide a broad picture of potential
impacts.
    As explained in section IV.A.2 of this preamble, the revised
emissions limits for existing HMIWI are based on the average of the
best performing 12 percent of sources for each pollutant in each
subcategory. This final action requires varying degrees of improvements
in performance by most HMIWI. Depending on the current configuration of
each unit and air pollution controls, the improvements could be
achieved either through the addition of add-on APCD, improvement of
existing add-on APCD, increase in sorbent usage rates, and various
combustion improvements. More specifically, the improvements
anticipated include: Most wet scrubber-controlled units adding a fabric
filter-based system for improved control of PM and metals; most units
with fabric filter-based systems adding a packed-bed wet scrubber for
improved control of HCl; adding activated carbon injection or
increasing activated carbon usage rate for improved Hg and dioxin
control; upgrading fabric filter performance for improved control of PM
and metals; increasing lime or caustic

use for improved control of HCl and, in a few instances,
SO2; and combustion improvements primarily associated with
decreasing CO emissions. We also project that a few units may require
add-on controls (SNCR) to meet the revised NOX emissions
levels. Facilities may resubmit their most recent compliance test data
for each pollutant if the data show that their HMIWI meets the revised
emissions limits. In these instances, facilities must certify that the
test results are representative of current operations. Those facilities
would then not be required to test for those pollutants to prove
initial compliance with the revised emissions limits.

A. What Are the Primary Air Impacts?

    EPA estimates that reductions of approximately 393,000 pounds per
year (lb/yr) of the regulated pollutants would be achieved if all
existing HMIWI improved performance to meet the revised emissions
limits. If all HMIWI selected an alternative disposal method,
reductions of approximately 1.52 million lb/yr would be achieved. Table
4 shows the estimated reductions by pollutant for the two scenarios for
the 57 HMIWI currently operating.

     Table 4--Projected Emissions Reductions for MACT Compliance and
             Alternative Disposal Options for Existing HMIWI
------------------------------------------------------------------------
                                         Reductions        Reductions
                                      achieved through  achieved through
              Pollutant               meeting MACT (lb/    alternative
                                             yr)        disposal (lb/yr)
------------------------------------------------------------------------
HCl.................................     168,000           198,000
CO..................................       1,140            20,200
Pb..................................         313               420
Cd..................................          15.6              35.1
Hg..................................         605               682
PM..................................       3,170            89,900
CDD/CDF, total......................           0.0678            0.0985
CDD/CDF, TEQ........................           0.00145           0.00183
NOX.................................     146,000         1,080,000
SO2.................................      73,700           126,000
                                     -----------------------------------
    Total...........................     393,000         1,520,000
------------------------------------------------------------------------

B. What Are the Water and Solid Waste Impacts?

    EPA estimates that, based on the MACT compliance option,
approximately 3,840 tons per year (tpy) of additional solid waste and
86,000 gallons per year (gpy) of additional wastewater would be
generated as a result of operating additional controls or using
increased amounts of various sorbents.
    EPA estimates that, based on the alternative disposal option,
approximately 15,100 tpy of additional solid waste would be sent to
landfills. This option would result in an estimated 5.40 million gpy in
wastewater impacts.

C. What Are the Energy Impacts?

    EPA estimates that approximately 9,530 megawatt-hours per year
(MWh/yr) of additional electricity would be required to support the
increased control requirements associated with the MACT compliance
option.
    For the alternative disposal option, EPA estimates that
approximately 12,400 MWh/yr of additional electricity would be required
to operate the autoclaves.

D. What Are the Secondary Air Impacts?

    Secondary air impacts associated with the MACT compliance option
are direct impacts that result from the increase in natural gas and/or
electricity use that we estimate may be required to enable facilities
to achieve the revised emissions limits. We estimate that the
adjustments could result in emissions of 279 lb/yr of PM; 3,260 lb/yr
of CO; 2,650 lb/yr of NOX; and 1,780 lb/yr of SO2
from the increased electricity and natural gas usage.
    For the alternative disposal option, EPA estimates secondary air
impacts of 692 lb/yr of PM; 5,040 lb/yr of CO; 2,550 lb/yr of
NOX; and 4,980 lb/yr of SO2 from the additional
electricity that would be required to operate the autoclaves. In
addition, EPA estimates that landfilling would result in an additional
626 tpy of methane and 0.0330 lb/yr of mercury emissions.

E. What Are the Cost and Economic Impacts?

    EPA estimates that for the MACT compliance option, the national
total costs for the 57 existing HMIWI to comply with this final action
would be approximately $15.5 million in each of the first 3 years of
compliance. This estimate includes the costs that would be incurred
based on the anticipated performance improvements (i.e., costs of new
APCD and improvements in performance of existing APCD), and the
additional monitoring (i.e., annual control device inspections),
testing (i.e., initial EPA Method 22 of appendix A-7 test and initial
compliance testing), and recordkeeping and reporting costs that would
be incurred by all 57 HMIWI as a result of this final action.
Approximately 95 percent of the estimated total cost in the first year
is for emissions control, and the remaining 5 percent is for
monitoring, testing, recordkeeping and reporting.
    EPA estimates that for the alternative disposal option, the
national total costs for the 57 existing HMIWI to dispose of their
solid waste by autoclaving and landfilling would be approximately $10.6
million per year. This estimate includes the costs that would be
incurred based on the purchase and operation of autoclaves and the
projected landfill tipping fees that would be incurred based on the
volume of waste to be landfilled.
    Currently, there are 57 existing HMIWI at 51 facilities. They may
be divided into two broad categories: (1) Captive HMIWI, which are co-
owned and co-located with generating facilities and provide on-site
incineration services for waste generated by the hospital, research
facility, university, or pharmaceutical operations; and (2) commercial
HMIWI, which provide commercial incineration services for waste
generated off-site by firms unrelated to the firm that owns the HMIWI.
EPA analyzed the impacts on

captive HMIWI and commercial HMIWI using different methods. Of the 57
HMIWI, 14 are commercial and 43 are captive.
    Owners of captive HMIWI may choose to incur the costs of complying
with the revised HMIWI standards or close the HMIWI and switch to
another disposal technology like autoclaving and landfilling or have
their waste handled by a commercial disposal service. EPA's estimate of
autoclaving and landfilling costs indicate that even without additional
regulatory costs, the costs of autoclaving and landfilling may be lower
than the costs of incinerating. However, even if all owners of captive
HMIWI choose to continue to operate with the additional regulatory
cost, the cost-to-sales ratios for firms owning captive HMIWI are low.
This reflects the relatively small share of overall costs that are
associated with hospital/medical/infectious waste management at these
firms. Of the 35 firms owning captive HMIWI, 22 have costs of
compliance that are less than 0.1 percent of firm sales. Of the 13 with
costs exceeding 0.1 percent of sales, the largest cost-to-sales ratio
is at a captive hospital HMIWI, and is equal to 0.995 percent.
Therefore, EPA expects no significant impact on the prices and
quantities of the underlying services of the owners of the captive
HMIWI, whether the costs are passed on or absorbed.
    Impacts on commercial HMIWI are analyzed using the simplifying
assumption that they operate as regional monopolists (in general, only
one HMIWI is considered as a treatment option by generators located
nearby). The approach to modeling the impact for commercial HMIWI seems
very appropriate for all of the facilities except for one. The other
commercial HMIWI facilities have costs of compliance that are no more
than 2.0 percent of revenues. That one facility has a ratio of
approximately 45 percent. As noted previously, this facility is a
regional monopolist and is able to raise the price by more than the per
unit cost increase. We expect there to be a reduction in the amount of
its services demanded due to the price change. Because of closures of
captive HMIWI, there may also be an increase in the demand for its
services that may reduce the decrease in revenues associated with the
price increase. For more details regarding EPA's analysis of the
economic impacts, see the July 2009 docket entry entitled ``Economic
Impacts of Revised MACT Standards for Hospital/Medical/Infectious Waste
Incinerators.''

VI. Impacts of the Final Action for New Units

    Information provided to EPA indicates that negative growth has been
the trend for HMIWI for the past several years. While existing units
continue to shut down, since promulgation of the HMIWI NSPS in 1997,
four new units have been constructed and one unit has been
reconstructed. This information indicates that in the absence of
further regulation, new HMIWI may be built. However, based on the
stringency of revisions being promulgated for the NSPS, sources would
likely respond to the final rule by choosing not to construct new HMIWI
and would utilize alternative waste disposal options rather than incur
the costs of compliance.
    Considering this information, EPA does not anticipate any new
HMIWI, and therefore, no impacts of the revised NSPS for new units. For
purposes of demonstrating that emissions reductions would result from
the NSPS in the unlikely event that a new unit is constructed, EPA
estimated emissions reductions and other impacts expected for each of
three HMIWI model plants.

A. What Are the Primary Air Impacts?

    EPA estimated emissions reductions for each of the model plants to
demonstrate that the NSPS would, if a new unit were built, reduce
emissions compared to a HMIWI meeting the current NSPS. Table 5 of this
preamble presents the emissions reductions for the HMIWI model plants.
The three model plants (with capacities of 100 lb/hr, 400 lb/hr, and
4,000 lb/hr) represent typical HMIWI. For pollutants where a ``zero''
value is shown, the model plant performance estimate meets the revised
new source limit, which is not surprising since the models are based on
the performance of the newest sources, which are among the best
performers in the industry.

                              Table 5--Emissions Reductions on a Model Plant Basis
----------------------------------------------------------------------------------------------------------------
                                                             Emissions reduction for HMIWI model plants (lb/yr)
                                                           -----------------------------------------------------
                         Pollutant                              100 lb/hr         400 lb/hr        4,000 lb/hr
                                                                capacity          capacity          capacity
----------------------------------------------------------------------------------------------------------------
HCl.......................................................                 0              45.8               968
CO........................................................                 0              7.97                 0
Pb........................................................                 0                 0              3.76
Cd........................................................                 0                 0             0.293
Hg........................................................                 0             0.194              2.40
PM........................................................                 0                 0               170
Dioxins/furans, total.....................................                 0       5.34 x 10-4                 0
Dioxins/furans, TEQ.......................................                 0       6.02 x 10-6                 0
NOX.......................................................               491             1,780                 0
SO2.......................................................              37.8              31.9                 0
                                                           -----------------------------------------------------
    Total.................................................               529             1,860             1,140
----------------------------------------------------------------------------------------------------------------

B. What Are the Water and Solid Waste Impacts?

    While EPA believes it is unlikely that any new HMIWI will be
constructed, we estimated the following water or solid waste impacts
associated with the revised NSPS for three different HMIWI model sizes:
For large units, we estimate 7,120 gpy of additional wastewater and
50.8 tpy of additional solid waste; for medium units, we estimate no
additional wastewater and 23.6 tpy of additional solid waste; and, for
small units, we estimate 29.7 gallons per year of additional wastewater
and 2.68 tpy of additional solid waste.

C. What Are the Energy Impacts?

    While EPA believes it is unlikely that any new HMIWI will be
constructed, we estimated the following energy impacts associated with
the revised NSPS for three different HMIWI model sizes: for large
units, we estimate that 280 MWh/yr of additional electricity would be

required to support the increased control requirements; for medium
units, we estimate 416 MWh/yr; and, for small units, we estimate 9.90
MWh/yr.

D. What Are the Secondary Air Impacts?

    Secondary air impacts for new HMIWI are direct impacts that would
result from the increase in natural gas and/or electricity use that we
estimate may be required to enable facilities to achieve the revised
emissions limits. While EPA believes it is unlikely that any new HMIWI
will be constructed, we estimated the secondary air impacts associated
with the revisions to the NSPS for three different HMIWI model sizes.
For large units, we estimate that the adjustments could result in
emissions of 15.6 lb/yr of PM; 114 lb/yr of CO; 57.4 lb/yr of
NOX; and 112 lb/yr of SO2. For medium units, we
estimate that the adjustments could result in emissions of 2.71 lb/yr
of PM; 119 lb/yr of CO; 142 lb/yr of NOX; and 0.938 lb/yr of
SO2. For small units, we estimate that the adjustments could
result in emissions of 0.551 lb/yr of PM; 4.02 lb/yr of CO; 2.03 lb/yr
of NOX; and 3.97 lb/yr of SO2.
    For the alternative disposal option, EPA estimated secondary air
impacts from the additional electricity that would be required to
operate autoclaves in lieu of each size of HMIWI. For large units, we
estimate secondary emissions of 65.5 lb/yr of PM; 478 lb/yr of CO; 241
lb/yr of NOX; and 471 lb/yr of SO2. For medium
units, we estimate secondary emissions of 4.98 lb/yr of PM; 36.3 lb/yr
of CO; 18.4 lb/yr of NOX; and 35.8 lb/yr of SO2.
For small units, we estimate secondary emissions of 1.25 lb/yr of PM;
9.09 lb/yr of CO; 4.60 lb/yr of NOX; and 8.98 lb/yr of
SO2. In addition, EPA estimates that an additional 58.5 tpy
of methane and 0.00308 lb/yr of mercury emissions would result from
landfilling waste that would have been processed in a large HMIWI, 3.29
tpy of methane and 0.000173 lb/yr of mercury emissions would result
from landfilling waste that would have been processed in a medium
HMIWI, and 0.549 tpy of methane and 0.0000289 lb/yr of mercury
emissions would result from landfilling waste that would have been
processed in a small HMIWI.

E. What Are the Cost and Economic Impacts?

    While EPA projects that three new HMIWI would be constructed in the
absence of the promulgated revisions, we believe that, in response to
the promulgated revisions, sources may decide against constructing new
HMIWI. Nevertheless, we estimated the following costs associated with
installation and operation of air pollution controls needed to meet the
revisions to the NSPS: for new large units, $1.08 million per year; for
new medium units, $116,000 per year; and, for new small units, $118,000
per year.
    EPA's analysis of impacts of the revisions to the HMIWI standards
on potential new HMIWI compares the with-regulation estimated prices
that would be charged by new large, medium, and small HMIWI to the
range of with-regulation prices estimated to be charged by existing
commercial HMIWI in various regional markets. This comparison indicates
that new large and medium commercial HMIWI may be viable, but new small
commercial HMIWI probably would not be viable. On the other hand,
generators of hospital/medical/infectious waste could have overarching
reasons to purchase and install a new small HMIWI. Comparison of
autoclave treatment coupled with off-site landfill disposal shows that,
for new facilities as for existing ones, autoclave/landfill treatment
and disposal is generally less costly than incineration. Thus, the
motivation to improve waste segregation to minimize the waste that must
be incinerated is likely to continue, although HMIWI treatment of some
wastes will continue to be required by regulation.

VII. Relationship of the Final Action to Section 112(c)(6) of the CAA

    Section 112(c)(6) of the CAA requires EPA to identify categories of
sources of seven specified pollutants to assure that sources accounting
for not less than 90 percent of the aggregate emissions of each such
pollutant are subject to standards under CAA Section 112(d)(2) or
112(d)(4). EPA has identified HMIWI as a source category that emits
five of the seven CAA Section 112(c)(6) pollutants: POM, dioxins,
furans, Hg, and PCBs. (The POM emitted by HMIWI is composed of 16
polyaromatic hydrocarbons (PAH) and extractable organic matter (EOM).)
In the Federal Register notice Source Category Listing for Section
112(d)(2) Rulemaking Pursuant to Section 112(c)(6) Requirements, 63 FR
17838, 17849, Table 2 (1998), EPA identified medical waste incinerators
(now referred to as HMIWI) as a source category ``subject to
regulation'' for purposes of CAA Section 112(c)(6) with respect to the
CAA Section 112(c)(6) pollutants that HMIWI emit. HMIWI are solid waste
incineration units currently regulated under CAA Section 129. For
purposes of CAA Section 112(c)(6), EPA has determined that standards
promulgated under CAA Section 129 are substantively equivalent to those
promulgated under CAA Section 112(d). (See id. at 17845; see also 62 FR
33625, 33632 (1997).) As discussed in more detail below, the CAA
Section 129 standards effectively control emissions of the five
identified CAA Section 112(c)(6) pollutants. Further, since CAA Section
129(h)(2) precludes EPA from regulating these substantial sources of
the five identified CAA Section 112(c)(6) pollutants under CAA Section
112(d), EPA cannot further regulate these emissions under that CAA
section. As a result, EPA considers emissions of these five pollutants
from HMIWI ``subject to standards'' for purposes of CAA Section
112(c)(6).
    As required by the statute, the CAA Section 129 HMIWI standards
include numeric emissions limits for the nine pollutants specified in
Section 129(a)(4). The combination of waste segregation, good
combustion practices, and add-on air pollution control equipment (dry
sorbent injection fabric filters, wet scrubbers, or combined fabric
filter and wet scrubber systems) effectively reduces emissions of the
pollutants for which emissions limits are required under CAA Section
129: Hg, CDD/CDF, Cd, Pb, PM, SO2, HCl, CO, and
NOx. Thus, the NSPS and EG specifically require reduction in
emissions of three of the CAA Section 112(c)(6) pollutants: dioxins,
furans, and Hg. As explained below, the air pollution controls
necessary to comply with the requirements of the HMIWI NSPS and EG also
effectively reduce emissions of the following CAA Section 112(c)(6)
pollutants that are emitted from HMIWI: POM and PCBs. Although the CAA
Section 129 HMIWI standards as promulgated in 1997 and as revised for
the 2009 final rule do not have separate, specific numerical emissions
limits for PCBs and POM, emissions of these two CAA Section 112(c)(6)
pollutants are effectively controlled by the same control measures used
to comply with the numerical emissions limits for the pollutants
enumerated in Section 129(a)(4). Specifically, as byproducts of
combustion, the formation of PCBs and POM is effectively reduced by the
combustion and post-combustion practices required to comply with the
CAA Section 129 standards. Any PCBs and POM that do form during
combustion are further controlled by the various post-combustion HMIWI
controls. The add-on PM control systems (either fabric filter or wet
scrubber) and activated carbon injection in the fabric filter-based
systems further reduce emissions of these organic pollutants, and also
reduce Hg

emissions, as is evidenced by HMIWI performance data. Specifically, the
post-MACT compliance tests at currently operating HMIWI that were also
operational at the time of promulgation of the 1997 standards show
that, for those units, the 1997 HMIWI MACT regulations reduced Hg
emissions by about 60 percent and CDD/CDF emissions by about 80 percent
from pre-MACT levels. (Note that these reductions do not reflect unit
shutdowns, units for which exemptions were granted, or new units.)
Moreover, similar controls have been demonstrated to effectively reduce
emissions of POM and PCBs from another incineration source category
(municipal solid waste combustors). It is, therefore, reasonable to
conclude that POM and PCB emissions are substantially controlled at all
57 HMIWI. Thus, while the final rule does not identify specific
numerical emissions limits for POM and PCB, emissions of those
pollutants are, for the reasons noted above, nonetheless ``subject to
regulation'' for purposes of Section 112(c)(6) of the CAA.
    In lieu of establishing numerical emissions limits for pollutants
such as PCBs and POM, CAA Section 129(a)(4) allows EPA to regulate
surrogate substances. While we have not identified specific numerical
limits for POM and PCB, we believe CO serves as an effective surrogate
for those pollutants, because CO, like POM and PCBs, is formed as a
byproduct of combustion. We believe that dioxins/furans also serve as
an effective surrogate for PCBs, because the compounds act similarly
and, thus, are expected to be controlled similarly using HMIWI
emissions control technology--e.g., wet scrubbers or fabric filters
(with or without activated carbon). Furthermore, recent HMIWI emissions
test data for PCBs and dioxins/furans show that HMIWI well-controlled
for dioxins/furans also achieve low PCB emissions. (See 2008 memorandum
entitled ``Documentation of HMIWI Test Data Database,'' which is
included in the docket.) It should also be noted that PCBs are
generally found in higher concentrations than dioxins/furans (also the
case for HMIWI), so HMIWI equipped with the aforementioned emissions
controls would be even more effective at reducing PCB emissions.
Consequently, we have concluded, in response to the public comments
submitted on this issue, that the emissions limits for CO function as a
surrogate for control of both POM and PCBs, and the limits for dioxins/
furans function as a surrogate for PCBs, such that it is not necessary
to promulgate numerical emissions limits for POM and PCBs with respect
to HMIWI to satisfy CAA Section 112(c)(6).
    To further address POM and PCB emissions, the final rule also
includes revised waste management plan provisions that encourage
segregation of the types of wastes that lead to these emissions, such
as chlorinated plastics and PCB-containing wastes.

VIII. Statutory and Executive Order Reviews

A. Executive Order 12866: Regulatory Planning and Review

    Under Executive Order 12866 (58 FR 51735; October 4, 1993), this
action is a ``significant regulatory action'' because it is likely to
raise novel legal or policy issues arising out of legal mandates, the
President's priorities, or the principles set forth in the Executive
Order. Accordingly, EPA submitted this action to the Office of
Management and Budget (OMB) for review under Executive Order 12866, and
any changes made in response to OMB recommendations have been
documented in the docket for this action.

B. Paperwork Reduction Act

    The information collection requirements in this rule have been
submitted for approval to OMB under the Paperwork Reduction Act, 44
U.S.C. 3501 et seq. The information collection requirements are not
enforceable until OMB approves them. The Information Collection Request
(ICR) documents prepared by EPA have been assigned EPA ICR number
2335.02 for subpart Ce, 40 CFR part 60, and 1730.08 for subpart Ec, 40
CFR part 60.
    The requirements in this final action result in industry
recordkeeping and reporting burden associated with review of the
amendments for all HMIWI, EPA Method 22 of appendix A-7 testing for all
HMIWI, and inspections of scrubbers, fabric filters, and other air
pollution control devices that may be used to meet the emissions limits
for all HMIWI. Stack testing and development of new parameter limits
would be necessary for HMIWI that need to make performance improvements
in order to meet the emissions limits and for HMIWI that, prior to this
final action, have not been required to demonstrate compliance with
certain pollutants. Any new HMIWI would also be required to
continuously monitor CO emissions. New HMIWI equipped with fabric
filters would also be required to purchase bag leak detectors.
    The annual average burden associated with the EG over the first 3
years following promulgation of this final action is estimated to be
44,229 hours at a total annual labor cost of $1,871,571. The total
annualized capital/startup costs and operation and maintenance (O&M)
costs associated with the monitoring requirements, EPA Method 22 of
appendix A-7 testing, storage of data and reports, and photocopying and
postage over the three year period of the ICR are estimated at
$1,410,168 and $641,591 per year, respectively. (The annual inspection
costs are included under the recordkeeping and reporting labor costs.)
The annual average burden associated with the NSPS over the first three
years following promulgation of this final action is estimated to be
2,705 hours at a total annual labor cost of $102,553. The total
annualized capital/startup costs are estimated at $137,658, with total
operation and maintenance costs of $116,192 per year. Burden is defined
at 5 CFR 1320.3(b).
    EPA may not conduct or sponsor, and a person is not required to, a
collection of information unless it displays a valid OMB control
number. The OMB control numbers for EPA's regulations in 40 CFR are
listed in 40 CFR part 9. When this ICR is approved by OMB, the EPA will
publish a technical amendment to 40 CFR part 9 in the Federal Register
to display the OMB control numbers for the approved information
collection requirements contained in this final rule.

C. Regulatory Flexibility Act

    The Regulatory Flexibility Act (RFA) generally requires an agency
to prepare a regulatory flexibility analysis of any rule subject to
notice and comment rulemaking requirements under the Administrative
Procedures Act or any other statute unless the EPA certifies that the
final action will not have a significant economic impact on a
substantial number of small entities. Small entities include small
businesses, small government organizations, and small government
jurisdictions.
    For purposes of assessing the impacts of this final action on small
entities, small entity is defined as follows: (1) A small business as
defined by the Small Business Administration's (SBA) regulations at 13
CFR 121.201; (2) a small governmental jurisdiction that is a government
of a city, county, town, school district or special district with a
population of less than 50,000; or (3) a small organization that is any
not-for-profit enterprise that is independently owned and operated and
is not dominant in its field.
    After considering the economic impacts of this final rule on small
entities, I certify that this action will not

have a significant economic impact on a substantial number of small
entities. The one small entity directly regulated by this final action
is a small business that owns two HMIWI. We have determined that this
one small entity may experience an impact of approximately $3.15
million per year to comply with the final rule, resulting in a cost-to-
sales ratio of approximately 45 percent. (See 2009 report ``Economic
Impacts of Revised MACT Standards for Hospital/Medical/Infectious Waste
Incinerators,'' which is included in the docket for today's
rulemaking.) The one small entity is a company in Maryland, which owns
and operates a commercial facility at that location. There are only
nine other commercial facilities, which are owned and operated by other
companies, and the closest are in North Carolina and Ohio. Therefore,
the entity is a regional monopolist and is able to raise the price by
more than the per unit cost increase. We expect there to be a reduction
in the amount of its services demanded due to the price change. Because
of closures of captive HMIWI there may also be an increase in the
demand for its services that may reduce the decrease in revenues
associated with the price increase.
    Two other entities are defined as borderline small: Their parent
company sales or employment in 2008 are above the SBA size-cutoff for
small entities in their NAICS codes, but are near enough to the size
cut-off that variations in sales or employment over time might move
them below the small business criterion. Based on 2008 sales data for
these two entities, the cost-to-sales ratio is less than 1 percent for
one entity and 1.4 percent for the other. It should be noted that the
entity with the higher cost-to-sales ratio (1.4 percent) is a
commercial unit and would have the ability to pass the cost along to
their customers and would be expected to be able to afford compliance.
Therefore, neither entity is likely to incur significant impacts. (See
2009 memorandum entitled ``Updated Sales Information for Companies
Considered Borderline Small Entities,'' which is included in the docket
for today's rulemaking.)
    Although the final rule will not have a significant economic impact
on a substantial number of small entities, EPA nonetheless conducted an
analysis of the impacts of the final rule on the directly regulated
small entity and has tried to reduce the impact of this rule on small
entities, to the extent allowed under the CAA MACT floor rulemaking.
Our impacts analysis is contained in the docket for today's final
rulemaking. For each subcategory of HMIWI, we are promulgating
emissions limits that are based on the MACT floor level of control,
which is the minimum level of stringency that can be considered in
establishing MACT standards. Under the CAA and the case law EPA can set
standards no less stringent than the MACT floor. Therefore, we were
unable to reduce the impact of the emissions limits on the small entity
that would be regulated by the final rule. However, we worked to
minimize the costs of testing and monitoring requirements in light of
our final impacts analysis, to the extent possible under the statute.

D. Unfunded Mandates Reform Act

    This final action contains no Federal mandates under the provisions
of Title II of the Unfunded Mandates Reform Act (UMRA), 2 U.S.C. 1531-
1538 for State, local, or Tribal governments or the private sector.
This final action imposes no enforceable duty on any State, local or
Tribal governments or the private sector. Therefore, this final action
is not subject to the requirements of Section 202 or 205 of the UMRA.
    This final action is also not subject to the requirements of
Section 203 of UMRA because it contains no regulatory requirements that
might significantly or uniquely affect small governments. This final
action contains no requirements that apply to such governments, imposes
no obligations upon them, and will not result in expenditures by them
of $100 million or more in any one year or any disproportionate impacts
on them.

E. Executive Order 13132: Federalism

    This action does not have Federalism implications. It will not have
substantial direct effects on the States, on the relationship between
the national government and the States, or on the distribution of power
and responsibilities among the various levels of government, as
specified in Executive Order 13132. This final action will not impose
substantial direct compliance costs on State or local governments, and
will not preempt State law. Thus, Executive Order 13132 does not apply
to this action.

F. Executive Order 13175: Consultation and Coordination With Indian
Tribal Governments

    This action does not have Tribal implications, as specified in
Executive Order 13175 (65 FR 67249; November 9, 2000). EPA is not aware
of any HMIWI owned or operated by Indian Tribal governments. Thus,
Executive Order 13175 does not apply to this action.

G. Executive Order 13045: Protection of Children From Environmental
Health and Safety Risks

    EPA interprets Executive Order 13045 (62 FR 19885; April 23, 1997)
as applying to those regulatory actions that concern health or safety
risks, such that the analysis required under section 5-501 of the Order
has the potential to influence the regulation. This final action is not
subject to Executive Order 13045 because it is based solely on
technology performance.

H. Executive Order 13211: Actions That Significantly Affect Energy
Supply, Distribution or Use

    This action is not a ``significant energy action'' as defined in
Executive Order 13211 (66 FR 28355; May 22, 2001) because it is not
likely to have a significant adverse effect on the supply,
distribution, or use of energy. EPA estimates that the requirements in
this final action would cause most HMIWI to modify existing air
pollution control devices (e.g., increase the horsepower of their wet
scrubbers) or install and operate new control devices, resulting in
approximately 9,530 MWh/yr of additional electricity being used.
    Given the negligible change in energy consumption resulting from
this final action, EPA does not expect any significant price increase
for any energy type. The cost of energy distribution should not be
affected by this final action at all since the action would not affect
energy distribution facilities. We also expect that any impacts on the
import of foreign energy supplies, or any other adverse outcomes that
may occur with regards to energy supplies would not be significant. We,
therefore, conclude that if there were to be any adverse energy effects
associated with this final action, they would be minimal.

I. National Technology Transfer and Advancement Act

    Section 12(d) of the National Technology Transfer and Advancement
Act of 1995 (``NTTAA''), Public Law 104-113 (15 U.S.C. 272 note)
directs EPA to use voluntary consensus standards (VCS) in its
regulatory activities unless to do so would be inconsistent with
applicable law or otherwise impractical. Voluntary consensus standards
are technical standards (e.g., materials specifications, test methods,
sampling procedures, and business practices) that are developed or
adopted by VCS bodies. NTTAA directs EPA to provide Congress, through
OMB, explanations when the EPA decides not to use available and
applicable VCS.

    This final rulemaking involves technical standards. EPA has decided
to use two VCS in this final rule. One VCS, ASME PTC 19.10-1981, ``Flue
and Exhaust Gas Analyses,'' is cited in this final rule for its manual
method of measuring the content of the exhaust gas as an acceptable
alternative to EPA Method 3B of appendix A-2. This standard is
available from the American Society of Mechanical Engineers (ASME),
P.O. Box 2900, Fairfield, NJ 07007-2900; or Global Engineering
Documents, Sales Department, 15 Inverness Way East, Englewood, CO
80112.
    Another VCS, ASTM D6784-02, ``Standard Test Method for Elemental,
Oxidized, Particle-Bound and Total Mercury Gas Generated from Coal-
Fired Stationary Sources (Ontario Hydro Method),'' is cited in this
final rule as an acceptable alternative to EPA Method 29 of appendix A-
8 (portion for mercury only) for measuring mercury. This standard is
available from the American Society for Testing and Materials (ASTM),
100 Barr Harbor Drive, Post Office Box C700, West Conshohocken, PA
19428-2959; or ProQuest, 300 North Zeeb Road, Ann Arbor, MI 48106.
    While the EPA has identified 16 VCS as being potentially applicable
to this final rule, we have decided not to use these VCS in this
rulemaking. The use of these VCS would be impractical because they do
not meet the objectives of the standards cited in this rule. See the
docket for this rule for the reasons for these determinations.
    Under 40 CFR 60.13(i) of the NSPS General Provisions, a source may
apply to EPA for permission to use alternative test methods or
alternative monitoring requirements in place of any required testing
methods, performance specifications, or procedures in the final rule
and any amendments.

J. Executive Order 12898: Federal Actions To Address Environmental
Justice in Minority Populations and Low-Income Populations

    Executive Order 12898 (59 FR 7629) (February 16, 1994) establishes
Federal executive policy on environmental justice. Its main provision
directs Federal agencies, to the greatest extent practicable and
permitted by law, to make environmental justice part of their mission
by identifying and addressing, as appropriate, disproportionately high
and adverse human health or environmental effects of their programs,
policies, and activities on minority populations and low-income
populations in the United States.
    EPA has determined that this final rule will not have
disproportionately high and adverse human health or environmental
effects on minority or low-income populations because it increases the
level of environmental protection for all affected populations without
having any disproportionately high and adverse human health or
environmental effects on any population, including any minority or low-
income populations.
    This action would establish national standards that would result in
reductions in emissions of HCl, CO, Cd, Pb, Hg, PM, CDD/CDF,
NOx and SO2 from all HMIWI and thus decrease the
amount of such emissions to which all affected populations are exposed.

K. Congressional Review Act

    The Congressional Review Act, 5 U.S.C. 801, et seq., as added by
the Small Business Regulatory Enforcement Fairness Act of 1996,
generally provides that before a rule may take effect the agency
promulgating the rule must submit a rule report, which includes a copy
of the rule, to each House of Congress and to the Comptroller General