not know of any technical reason that activated carbon injection could
not be applied to reduce Hg emissions at MH units. We are requesting
comment and additional information on the feasibility of using this
technology on MH units.
    Thus, given the factors discussed above, we are proposing limits
for Hg based on the beyond-the-floor option described above. However,
we are requesting comment on this approach and the beyond-the-floor
limits for Hg at MH units and request information on other factors and
any data available that we should consider in our final rulemaking.
    We also considered whether we should set beyond-the-floor emission
limits for CO. The emissions reductions and cost associated with this
are referred to as option 3 in Tables 8 and 9 of this preamble. We
estimate that to apply MACT control option 3, which would require
either the use of an afterburner or thermal oxidizer, could require as
much as 1,700 million cubic feet of natural gas a year to be burned,
resulting in NOX and CO emissions of 84 and 70 TPY,
respectively. Therefore, given these factors, we are not recommending
going beyond-the-floor with option 3. We are requesting comment on
whether to require MH units to meet the 100 ppmv CO limit, considering
the potential emissions of NOX and the cost impacts on
municipalities of applying this option.
    The results of the beyond-the-floor analysis are documented in the
memorandum ``Analysis of Beyond the Maximum Achievable Control
Technology (MACT) Floor Controls for Existing SSI Units'' found in the
SSI docket (EPA-HQ-OAR-2009-0559). Table 1 in this preamble summarizes
the proposed emissions limits for existing SSI units.
2. Beyond-the-Floor Analysis for New Sources
    We did not identify any technologies or methods to achieve emission
limits more stringent than the MACT floor limits for new units based on
the lowest emitting FB incinerators. The control technologies necessary
to achieve the MACT floor levels are generally the most effective
controls available: FF for PM, Cd and Pb control; packed bed scrubbers
for SO2 and HCl control; afterburners for CO control; and
activated carbon injection for CDD/CDF and Hg control. In addition,
incremental additions of activated carbon have not been proven to
achieve further reductions above the projected flue gas concentration
estimated to achieve the limits for new sources. Data gathered do not
indicate that any FB incinerators operate NOX controls, such
as SNCR, SCR, or FGR because the NOX emissions are already
low. In light of the technical feasibility, costs, energy, and nonair
quality health and environmental impacts discussed in this section, we
have determined it is not reasonable to establish beyond-the-floor
limits for existing and new SSI units. Table 2 in this preamble
summarizes the proposed emissions limits for new SSI units.

E. Rationale for Performance Testing and Monitoring Requirements

    We are proposing that all new and existing SSI units meet the
following requirements:

     Initial and annual emissions performance tests (or
continuous emissions monitoring as an alternative).
     Annual inspections of scrubbers, FF, and other air
pollution control devices that may be used to meet the emission
limits.
     Annual visual emissions test of ash handling
procedures.
     Control device parameter monitoring for wet scrubbers,
FF, ESP, activated carbon injection, and afterburners, and other
approved control devices.
     Monitoring of bypass stack use if installed at an
affected unit.
     Periodic performance evaluations of continuous
monitoring systems.

    These proposed requirements were selected to provide additional
assurance that sources continue to operate at the levels established
during their initial performance test. The visual emissions test of ash
handling procedures and annual control device inspections have been
adopted for HMIWI, another CAA section 129 source category. Hospital,
Medical, and Infectious Waste Incineration standards (74 FR 51367)
contain these requirements to ensure that the ash which may contain
metals, is not emitted to the atmosphere through fugitive emissions and
that control devices are maintained properly.

The large and small MWC standards also have similar fugitive ash
monitoring requirements. In addition, the CISWI rule requires a Method
22 (of appendix A-7) visible emissions test of the ash handling
operations to be conducted during the annual compliance test for all
subcategories except waste-burning kilns, which do not have ash
handling systems. We propose to require the fugitive ash monitoring
provisions that are contained in the HMIWI, CISWI, and MWC rules. The
HMIWI, CISWI, and MWC units are incineration devices combusting waste
and have ash handling similar to SSI units. Consequently, we believe
that the requirements for fugitive ash handling in the HMIWI and MWC
standards can be applied to SSI units. We request comment on whether
the ash handling requirements for MWC and HMIWI are appropriate for
SSI, and if not, what requirements should be imposed.
    The proposed rules would allow sources to use the results of
emissions tests conducted within the previous 2 years to demonstrate
initial compliance with the proposed emission limits for all the CAA
section 129 pollutants as long as the sources certify that the previous
test results are representative of current operations. Such tests must
have been conducted using the test methods specified in the SSI rules
and must be the most recent tests performed on the unit. Those sources,
whose previous emissions tests do not demonstrate compliance with 1 or
more of the revised emission limits, would be required to conduct
another emissions test for those pollutants. This allowance to use
previous tests would minimize the burden to affected sources.
Information collected by EPA shows tests have been conducted on SSI for
Title V, State testing requirements, and OW 503 rule requirements for
many of the CAA section 129 pollutants. We seek comment on the
appropriateness of the use of previously-conducted performance tests.
    The proposed rule also would allow for reduced testing of PM, Cd,
Pb, Hg, SO2, HCl, NOX and CO (for existing
sources only). We are proposing to allow facilities with test data for
listed pollutants that show emissions are less than 75 percent of the
applicable emission limits to be able to qualify for testing for these
pollutants once every 3 years. The reduced testing allowance and
compliance margin provides flexibility and incentive to sources that
operate well within the emission standard, and timelier follow-through
on assuring that sources that are marginally in compliance will remain
in compliance.
    The proposed rule would allow for the following optional CEMS use:
CO CEMS for existing sources; and NOX CEMS, SO2
CEMS, PM CEMS, HCl CEMS, multi-metals CEMS, Hg CEMS, CDD/CDF CEMS,
ISTMMS and ISTDMS for existing and new sources and COMS. Some existing
SSI units may have CO CEMS, NOX CEMS, or SO2 CEMS
already to meet other regulatory or permit requirements, and we propose
to allow them to continue to use these monitors to demonstrate
continuous compliance with the SSI standards. The optional use of HCl
CEMS, multi-metals CEMS, CDD/CDF CEMS, ISTMMS, and ISTDMS would be
available on the date a final PS for these monitoring systems is
published in the Federal Register. The proposed monitoring provisions
are discussed in more detail below.
    Monitoring Provisions for All Control Devices. The proposed rules
would require monitoring the dry sludge feed rate, combustion chamber
temperature (or afterburner temperature), and sludge moisture content
to ensure that the incinerator operation parameters measured during the
compliance test are continually maintained.
    Monitoring Provisions for Wet Scrubbers. The proposed rules would
require monitoring the scrubber liquor flow rate and pH, and the
minimum pressure drop across each scrubber (or amperage to each
scrubber), to ensure that the scrubber operation parameters measured
during the compliance test are continually maintained.
    Monitoring Provisions for Activated Carbon Injection (Hg sorbent
injection). The proposed rules would require monitoring of activated
carbon (i.e., Hg sorbent) injection rate and carrier gas flow rate (or
carrier gas pressure drop) to ensure that the minimum sorbent injection
rate, measured during the compliance test, is continually maintained.
    Monitoring Provisions for FF. The proposed rules would require bag
leak detection system monitoring to ensure that the FF is operating
properly and that leaks in the filter media are quickly identified and
corrected on a continuous basis.
    Monitoring Provisions for Electrostatic Precipitators. The proposed
rules would require monitoring of the secondary voltage and secondary
amperage of the collection plates, calculating the secondary power
input to the collection plates (voltage multiplied by amperage) per ESP
section, and effluent water flow rate at the outlet of the ESP (for wet
ESP) to ensure that the ESP operating parameters measured during the
compliance test are maintained on a continuous basis.
    Monitoring Provisions for Afterburners. The proposed rules would
require monitoring of the temperature of afterburners.CO CEMS. The
proposed rules would require the use of CO CEMS on new SSI units. The
proposed rules would allow the use of CO CEMS on existing sources.
Owners and operators that use CO CEMS would be able to discontinue
their annual CO compliance test. The continuous monitoring of CO
emissions is an effective way of ensuring that the combustion unit is
operating properly. The proposed rules incorporate the use of PS-4B
Specifications and Test Procedures for Carbon Monoxide and Oxygen
Continuous Monitoring Systems in Stationary Sources) of appendix B of
40 CFR part 60.
    The proposed CO emission limits are based on data from annual stack
tests and compliance would be demonstrated by stack tests. The change
to use continuously-operated CO CEMS for measurement and enforcement of
the stack test-based emission limits must be carefully considered in
relation to an appropriate averaging period for data reduction. In past
EPA rulemakings for incineration units, EPA has selected averaging
times between 4 hours and 24 hours based on statistical analysis of
long-term CEMS data for a particular subcategory. Because CO CEMS data
available for SSI to perform such an analysis are insufficient to
determine an emission level that would correspond to a shorter
averaging period, EPA is proposing the use of a 24-hour block average
as appropriate to address potential changes in CO emissions. The 24-
hour block average would be calculated using Equation 19-19 in section
12.4.1 of EPA Method 19 of appendix A-7 of 40 CFR part 60. Existing
facilities electing to use CO CEMS as an optional method would be
required to notify EPA 1 month before starting use of CO CEMS and 1
month before stopping use of the CO CEMS. In addition, EPA specifically
requests comment on whether continuous monitoring of CO emissions
should be required for all existing SSI.
    PM CEMS. The proposed rules would allow the use of PM CEMS as an
alternative testing and monitoring method. Owners or operators who
choose to rely on PM CEMS would be able to discontinue their annual PM
compliance test. In addition, because units that demonstrate compliance
with the PM emission limits with a PM CEMS would also be meeting the
opacity standard, compliance demonstration with PM CEMS would be

considered a substitute for opacity testing or opacity monitoring.
Owners and operators who use PM CEMS also would be able to discontinue
their monitoring of ESP and scrubbers used to comply with the PM
emission limit for the following operating parameters: Wet scrubber
pressure drop, scrubber liquor flow rate, scrubber liquor pH, secondary
voltage of ESP collection plates, secondary amperage of ESP collection
plates, effluent water flow rate at the outlet of the ESP, and opacity
monitoring or testing to demonstrate continuous compliance with the
opacity limits. These operating parameters may still need to be
monitored to demonstrate compliance for other pollutants (e.g., HCl).
These parameter monitoring requirements were designed to ensure the
scrubber continues to operate in a manner that reduces PM emissions and
would not be necessary if PM is directly measured on a continuous
basis. The proposed amendments incorporate the use of PS-11
(Specifications and Test Procedures for Particulate Matter Continuous
Emissions Monitoring Systems at Stationary Sources) of appendix B of 40
CFR part 60 for PM CEMS and PS-11 QA Procedure 2 to ensure that PM CEMS
are installed and operated properly and produce good quality monitoring
data.
    The proposed PM emission limits are based on data from (normally
distributed or transferred to be normally distributed) annual stack
tests and compliance would generally be demonstrated by stack tests.
The use of PM CEMS for measurement and enforcement of the same stack
test-based emission limits must be carefully considered in relation to
an appropriate averaging period for data reduction. Because PM CEMS
data are unavailable for SSI, EPA is proposing that the use of a 24-
hour block average is appropriate to address potential changes in PM
emissions that cannot be accounted for with short term stack test data.
The 24-hour block average would be calculated using Equation 19-19 in
section 12.4.1 of EPA Method 19 of appendix A-7 of 40 CFR part 60. An
owner or operator of a SSI unit who wishes to use PM CEMS would be
required to notify EPA 1 month before starting use of PM CEMS and 1
month before stopping use of the PM CEMS.
    Other CEMS and Monitoring Systems. EPA also is proposing the
optional use of NOX CEMS, SO2 CEMS, HCl CEMS,
multi-metals CEMS, Hg CEMS, CDD/CDF CEMS, ISTMMS, and ISTDMS as
alternatives to the existing monitoring methods for demonstrating
compliance with the NOX, SO2, HCl, Pb, Cd and Hg,
and CDD/CDF emission limits. Because CEMS data for SSI are unavailable
for all subcategories for NOX, SO2, HCl and
metals, EPA concluded that the use of a 24-hour block average was
appropriate to address potential changes in emissions of
NOX, SO2, HCl and metals that cannot be accounted
for with short term stack test data. EPA has concluded that the use of
24-hour block averages would be appropriate to address emissions
variability, and EPA has included the use of 24-hour block averages in
the proposed rule. The 24-hour block averages would be calculated using
Equation 19-19 in section 12.4.1 of EPA Method 19 of appendix A of 40
CFR part 60. The proposed amendments incorporate the use of PS-2 of
appendix B of 40 CFR part 60 for NOX and SO2
CEMS. Although final PS are not yet available for HCl CEMS and multi-
metals CEMS, EPA is considering development of PS. The proposed rule
specifies that these options would be available to a facility on the
date a final PS is published in the Federal Register.
    The use of HCl CEMS would allow the discontinuation of monitoring
of the following operating parameters associated with scrubbers used to
comply with the HCl emission limits: scrubber liquor flow rate,
scrubber liquor pH, pressure drop across the scrubber (or amperage to
the scrubber), and the annual testing requirements for HCl. However,
some of these monitoring parameters may still be necessary to
demonstrate compliance with other pollutant emission limits. These
parameter monitoring requirements were designed to ensure the scrubber
continues to operate in a manner that reduces HCl emissions and would
not be necessary if HCl emissions are directly measured on a continuous
basis. EPA has proposed PS-13 (Specifications and Test Procedures for
Hydrochloric Acid Continuous Monitoring Systems in Stationary Sources)
of appendix B of 40 CFR part 60 and expects that PS-13 can serve as the
basis for HCl CEMS use at SSI. The procedures used in proposed PS-13
for the initial accuracy determination use the relative accuracy test,
a comparison against a reference method. EPA is taking comment on an
alternate initial accuracy determination procedure, similar to the one
in section 11 of PS-15 (Performance Specification for Extractive FTIR
Continuous Emissions Monitor Systems in Stationary Sources) of appendix
B of 40 CFR part 60 using the dynamic or analyte spiking procedure.
    EPA believes multi-metals CEMS can be used in many applications,
including SSI. EPA has monitored side-by-side evaluations of multi-
metals CEMS with EPA Method 29 of appendix A-8 of 40 CFR part 60 at
industrial waste incinerators and found good correlation. EPA also
approved the use of multi-metals CEMS as an alternative monitoring
method at hazardous waste combustors. EPA believes that proposed PS-10
(Specifications and Test Procedures for Multi-metals Continuous
Monitoring Systems in Stationary Sources) of appendix B of 40 CFR part
60 or other EPA PS to allow the use of multi-metals CEMS at SSI is an
appropriate alternative. We request comment on the appropriateness of
using multi-metals CEMS as a substitute for Cd and Pb performance
testing. The procedures used in proposed PS-10 for the initial accuracy
determination use the relative accuracy test, a comparison against a
reference method. EPA is taking comment on an alternate initial
accuracy determination procedure, similar to the one in section 11 of
PS-15 using the dynamic or analyte spiking procedure.
    EPA proposes the optional use of Hg CEMS (Performance Specification
12A--Specifications and Test Procedures for Total Vapor Phase Mercury
Continuous Emissions Monitoring Systems in Stationary Sources) or
ISTMMS (Performance Specification 12B--Specifications and Test
Procedures for Total Vapor Phase Mercury Continuous Emissions
Monitoring Systems from Stationary Sources Using a Sorbent Trap
Monitoring System or Appendix K of part 75).\16\ An owner or operator
of a SSI unit who wishes to use any CEMS or CASS would be required to
notify EPA 1 month before starting use of the CEMS or CASS and 1 month
before stopping use of the CEMS or CASS. The source would also have to
perform the annual performance test within 60 days of ceasing to use
the CEMS or CASS for compliance with the standard. Mercury sorbent flow
rate and carrier gas flow rate (or carrier gas pressure drop)
monitoring could be eliminated in favor of a multi-metals CEMS or Hg
CEMS; however CDD/CDF sorbent flow rate and carrier gas monitoring
would still be required as an indicator of CDD/CDF

control if ISTDMS or CDD/CDF CEMS are not used.
---------------------------------------------------------------------------

    \16\ EPA originally added PS-12A and PS-12B to Part 75 as part
of the Clean Air Mercury Rule (CAMR). The United States Court of
Appeals for the District of Columbia Circuit vacated CAMR on grounds
unrelated to the PS. New Jersey v. EPA; 517 F.3d 574 (DC Cir. 2008).
The Court's decision did not, in any way, address the
appropriateness of the procedures set forth in Appendix K. In 2009,
as part of the Portland Cement MACT, EPA proposed amending part 75
to add PS-12A and PS-12B. EPA currently intends to finalize those
specifications at the same time it takes final action on the
Portland cement MACT rule.
---------------------------------------------------------------------------

    The ISTMMS would entail use of a CASS with analysis of the samples
at set intervals using any suitable determinative technique that can
meet appropriate criteria. The option to use a CASS would take effect
on the date a final PS is published in the Federal Register. As with Hg
and multi-metal CEMS, use of integrated sorbent trap monitoring would
eliminate the requirement to monitor Hg sorbent injection rate but
would not eliminate the requirement to monitor CDD/CDF sorbent
injection rate because it also is an indicator of CDD/CDF control.
    The ISTDMS would entail use of a CASS and analysis of the sample
according to EPA Reference Method 23 of appendix A-7 of 40 CFR part 60.
The option to use a CASS would take effect on the date a final PS is
published in the Federal Register. Dioxin/furan sorbent injection rate
and carrier gas flow rate (or carrier gas pressure drop) monitoring and
CDD/CDF annual testing could be eliminated in favor of ISTDMS, but Hg
sorbent injection rate monitoring would not be eliminated because it
also is an indicator of Hg control.
    If integrated sorbent trap monitoring of CDD/CDF as well as multi-
metals CEMS, Hg CEMS, or ISTMMS are used, both Hg sorbent injection
rate monitoring and CDD/CDF sorbent injection rate monitoring could be
eliminated. These parameter monitoring requirements were designed to
ensure that control devices continue to be operated in a manner to
reduce CDD/CDF, metals and Hg emissions, and corresponding monitoring
is not needed if all of these pollutants are directly measured on an
ongoing basis. EPA requests comment on other parameter monitoring
requirements that could be eliminated upon use of any or all of the
optional CEMS and CASS discussed above. Table 10 of this preamble
presents a summary of the SSI operating parameters, the pollutants
influenced by each parameter and alternative monitoring options for
each parameter.

    Table 10--Summary of SSI Operating Parameters and Control Device
  Inspections, Pollutants Influenced by Each Parameter and Alternative
                  Monitoring Options for Each Parameter
------------------------------------------------------------------------
                                      Pollutants
  Operating parameter (control       influenced by
   device type associated with         operating          Alternative
     monitoring requirement)       parameter/control  monitoring options
                                        device
------------------------------------------------------------------------
Sludge feed rate (All)..........  All...............  None.
------------------------------------------------------------------------
Sludge moisture level (All).....  All...............  None.
------------------------------------------------------------------------
Temperature of combustion         All...............  None.
 chamber (or afterburner
 combustion chamber) (All).
------------------------------------------------------------------------
CDD/CDF sorbent flow rate         CDD/CDF...........  ISTDMS or CDD/CDF
 (Activated carbon injection).                         CEMS.
Carrier gas flow rate or carrier
 gas pressure drop (Activated
 carbon injection using CDD/CDF
 sorbent).
------------------------------------------------------------------------
Hg sorbent flow rate (Activated   Hg................  ISTMMS, Hg CEMS,
 carbon injection).                                    or multi-metals
                                                       CEMS.
Carrier gas flow rate or carrier
 gas pressure drop (Activated
 carbon injection using Hg
 sorbent).
------------------------------------------------------------------------
Scrubber pressure drop from each  PM, Cd, Pb........  PM CEMS, Pb CEMS,
 scrubber (Wet scrubber).                              or Cd CEMS.
------------------------------------------------------------------------
Scrubber liquor flow rate from    PM, Cd, Pb........  PM CEMS, multi-
 each scrubber (Wet scrubber).                         metals CEMS, Cd
                                                       CEMS, or Pb CEMS.
------------------------------------------------------------------------
Scrubber liquor flow rate from    HCl, SO2..........  HCl CEMS or SO2
 each scrubber (Wet scrubber).                         CEMS.
------------------------------------------------------------------------
Scrubber liquor pH from each      HCl, SO2..........  HCl CEMS or SO2
 scrubber (Wet scrubber).                              CEMS.
Secondary voltage and secondary   PM, Cd, Pb, Hg....  PM CEMS, Pb CEMS,
 amperage of collection plates                         or Cd CEMS.
 (All ESP).
Effluent flow rate (Wet ESP)....
------------------------------------------------------------------------
Temperature of afterburner......  CO................  None.
------------------------------------------------------------------------
Bag leak detection monitoring     PM, Cd, Pb, Hg....  None.
 system alarm time (FF).
------------------------------------------------------------------------
Air pollution control device      All...............  None.
 inspections.
------------------------------------------------------------------------
Time of visible emissions from    PM................  None.
 ash handling.
------------------------------------------------------------------------
Opacity from combustion stacks..  PM................  PM CEMS or COMS
                                                       (only if wet
                                                       scrubber is not
                                                       used).
------------------------------------------------------------------------

    Table 11 of this preamble presents a summary of the SSI test
methods and approved alternative compliance methods.

                   Table 11--Summary of SSI Test Methods and Approved Alternative Test Methods
----------------------------------------------------------------------------------------------------------------
                                                             Approved Alternative
    Pollutant/parameter            Test Methods \1\               methods \1\                  Comments
----------------------------------------------------------------------------------------------------------------
Cd.........................  Method 29 at 40 CFR part     Cd CEMS or Multi-metals     Cd CEMS or multi-metal
                              60, appendix A-8.            CEMS.                       CEMS are optional for all
                                                                                sources in lieu of annual
                                                                                Cd test.
CDD/CDF....................  Method 23 at 40 CFR part     ISTDMS....................  ISTDMS are optional for
                              60, appendix A-7.                                        all sources in lieu of
                                                                                annual CDD/CDF testing.
CO.........................  CO CEMS (new sources) and    CO CEMS (for existing       CO CEMS are optional for
                              Method 10, 10A, or 10B at    sources).                   existing sources in lieu
                              40 CFR part 60 appendix A-                               of annual CO test; CO
                              4.                                                       CEMS are required for new
                                                                                sources.
Flue and exhaust gas         Method 3A or 3B at 40 CFR    ASME PTC 19.10-1981 part    ..........................
 analysis.                    part 60, appendix A-2.       10.
HCl........................  Method 26 or Method 26A at   HCl CEMS..................  HCl CEMS are optional for
                              40 CFR part 60, appendix A-                              all sources in lieu of
                              8.                                                       annual HCl test.
Hg.........................  Method 29 at 40 CFR part     Method 30B at 40 CFR part   Multi-metal CEMS, Hg CEMS,
                              60, appendix A-8.            60, appendix A (when        or ISTMMS are optional
                                                           published in the Federal    for all sources in lieu
                                                           Register); Multi-metals     of annual Hg test.
                                                           CEMS; Hg CEMS (PS-12A);
                                                           ISTMMS (PS-12B of
                                                           Appendix B of part 75);
                                                           or ASTM D6784-02,
                                                           Standard Test Method for
                                                           Elemental Oxidized,
                                                           Particle Bound and Total
                                                           Mercury in Flue Gas
                                                           Generated from Coal-fired
                                                           Stationary Sources
                                                           (Ontario Hydro Method).
NOX........................  Method 7 or 7E at 40 CFR     NOX CEMS..................  NOX CEMS are optional for
                              part 60, appendix A-4.                                   all sources in lieu of
                                                                                annual NOX test.
Opacity....................  Method 9 of 40 CFR part 60,  PM CEMS, COMS.............  PM CEMS and COMS are
                              appendix A-4.                                            optional for all sources
                                                                                in lieu of annual opacity
                                                                                testing.
Pb.........................  Method 29 at 40 CFR part     Pb CEMS or Multi-metals     PB CEMS or multi-metal
                              60, appendix A-8.            CEMS.                       CEMS are optional for all
                                                                                sources in lieu of annual
                                                                                Pb test.
PM.........................  Method 5, at 40 CFR part     PM CEMS...................  PM CEMS are optional for
                              60, appendix A-3; Method                                 all sources in lieu of
                              26A or 29 at 40 CFR part                                 annual PM test required.
                              60, appendix A-8.
PM, Pb, Cd, Hg.............  Bag leak detection system    ..........................  Bag leak detection systems
                              or PM CEMS.                                              are required for units
                                                                                equipped with FF.
SO2........................  Method 6 or Method 6C at 40  HCl CEMS..................  SO2 CEMS are optional for
                              CFR part 60, appendix A-4.                               all sources in lieu of
                                                                                annual SO2 test.
Visible emissions of         Method 22 of appendix A-7    None......................
 fugitive ash.                of this part.
----------------------------------------------------------------------------------------------------------------
\1\ EPA Reference Methods in appendix A of 40 CFR part 60.

    This proposal contains no specific data availability requirements
for continuous monitoring systems. Generally, monitoring must be
conducted and emissions data must be collected at all times the SSI
unit is operating, except for periods of monitoring system malfunction,
repairs associated with monitoring system malfunction, and required
monitoring system quality assurance or quality control activities. We
seek comment on approaches to provide this data, e.g., redundant CEMS,
prescribed missing data procedures, owner- or operator-developed
missing data procedures, or parametric monitoring. EPA is considering
changing the averaging times for all CEMS and CASS from 24-hour block
averages to 12-hour rolling averages to be consistent with the
averaging times of the PS tests. We are requesting comment on the
change. Additionally, we seek comment on the proposed 4-hour rolling
averaging time for compliance with operating limits.
    The proposed rules would require repeat performance tests and
updates to the monitoring plan if any of the following process changes
occur: (1) A change in the process employed at the wastewater treatment
facility that affects the SSI unit, (2) a change in the air pollution
control devices used to comply with the emission limits and (3) an
increase in the allowable wastewater received from an industrial source
to the wastewater treatment facility. We are requesting comment on
these requirements and on the designation of what a process change is
at a SSI unit.
    The OW 503 standards allow compliance demonstration by analyzing
the pollutant concentration in the sludge ensuring the concentrations
are sufficiently low that emission limits may be met. We request
comment on whether facilities should be allowed to comply with the EG
and NSPS based on monitoring the content of the sludge entering the SSI
unit.
    In previous CAA section 129 standards, a waste management plan was
required to identify both the feasibility and the approach to
separating certain components of solid waste from the waste stream to
reduce the amount of toxic emissions from incinerated waste. Elements
of the waste management plan included identifying reasonably available
additional waste management measures, the cost and emission reductions
of the additional measures and other associated environmental or energy
impacts.
    As previously discussed, all SSI units are required to meet the
EPA's OW part 503 standards. Part 503 establishes daily average
concentration limits for Pb, Cd

and other metals in sewage sludge that is disposed of by incineration.
Part 503 also requires that SSI units meet the National Emission
Standards for Beryllium and Mercury in subparts C and E, respectively,
of 40 CFR part 61. In order to meet the 40 CFR part 503 standards,
facilities are already incorporating management practices and measures
to reduce waste and limit the concentration of pollutants in the sludge
sent to SSI units, such as segregating contaminated and uncontaminated
wastes and establishing discharge limits or pre-treatment standards for
non-domestic users discharging wastewater to POTW. We are requesting
comment on the need for a waste management plan for SSI units in the
promulgated rules.

F. Rationale for Recordkeeping and Reporting Requirements

    Section 129 of the CAA requires the EPA to develop regulations that
include requirements for reporting the results of testing and
monitoring performed to determine compliance with the standards and
guidelines. The requirements must specify the form and frequency of the
reports demonstrating compliance. If there are no exceedances,
compliance reports are submitted annually. However, if there is an
exceedance, reports showing the exceedance of any standard or guideline
must be submitted separately for review and potential enforcement
action. Copies of testing and monitoring results must be maintained on
file at the affected facility. Other types of records are necessary to
ensure that all provisions of the standards or guidelines are being
met. Examples include siting analyses and operator training and
qualification records.

G. Rationale for Operator Training and Qualification Requirements

    The proposed standards and guidelines include operator training and
qualification requirements for SSI unit operators. These requirements
provide flexibility by allowing State approved training and
qualification programs. Where there are no State approved programs, the
proposed regulations include minimum requirements for training and
qualification. The minimum requirements include completion of a
training course covering specified topics.
    In developing these requirements, training and qualification
programs currently proposed or promulgated for other types of solid
waste incineration units were reviewed to develop requirements
appropriate for the SSI source category.

H. Rationale for Siting Requirements

    Section 129 of the CAA states that performance standards for new
solid waste incineration units must incorporate siting requirements
that minimize, on a site-specific basis and to the maximum extent
practicable, potential risks to public health or the environment. In
accordance with section 129, the EPA is proposing site selection
criteria for SSI units that commence construction on or after the date
of proposal of this rule (i.e., ``new'' units). The siting requirements
would not apply to existing SSI units.
    The siting requirements in this proposal would require the owner or
operator of a new unit to prepare an analysis of the impacts of the new
unit. The owner or operator must consider air pollution control
alternatives that minimize, on a site-specific basis, to the maximum
extent practicable, potential risks to public health or the
environment. In considering such alternatives, the owner or operator
may consider costs, energy impacts, nonair environmental impacts, or
any other factors related to the practicability of the alternatives. To
avoid duplication, analyses of facility impacts prepared to comply with
State, local, or other Federal regulatory requirements may be used to
satisfy this requirement, provided they include the consideration of
air pollution control alternatives specified previously. Such State,
local, or Federal requirements may include, but are not limited to,
State-specific criteria or national criteria established by the
National Environmental Policy Act or new source review permitting
requirements. The owner or operator must submit the siting information
to EPA prior to commencing construction of the facility.

I. What are the SSM provisions?

    The United States Court of Appeals for the District of Columbia
Circuit vacated portions of 2 provisions in EPA's CAA section 112
regulations governing the emissions of HAP during periods of SSM.
Sierra Club v. EPA, 551 F.3d 1019 (DC Cir. 2008), cert. denied, 130 S.
Ct. 1735 (U.S. 2010). Specifically, the Court vacated the SSM exemption
contained in 40 CFR 63.6(f)(1) and 40 CFR 63.6(h)(1), (the ``General
Provisions Rule,'') that EPA promulgated under section 112 of the CAA.
When incorporated into CAA section 112(d) regulations for specific
source categories, these 2 provisions exempt sources from the
requirement to comply with the otherwise applicable CAA section 112(d)
emission standard during periods of SSM. The Court found that the
definition of ``emission standards,'' which appears at 42 U.S.C.
7602(k), and which applies equally to sections 112 and 129, requires
EPA to apply MACT emissions standards on a continuous basis, thereby
precluding exemptions applied for malfunctions or other singular
events.\17\ Thus, the legality of source category-specific SSM
exemptions in rules promulgated pursuant to section 129 is
questionable. Therefore, consistent with Sierra Club v. EPA, EPA is
proposing that the standards in this rule apply at all times. EPA has
attempted to ensure that we have not incorporated into proposed
regulatory language any provisions that are inappropriate, unnecessary,
or redundant in the absence of a SSM exemption. We are specifically
seeking comment on whether there are any such provisions that we have
inadvertently incorporated or overlooked. If we receive relevant data
that would warrant different standards, we may set those standards in
the final rule.
---------------------------------------------------------------------------

    \17\ 551 F.3d at 1027.
---------------------------------------------------------------------------

    We note that the General Provisions of 40 CFR part 60 include
provisions that are inconsistent with the proposed requirement that the
SSI emissions standards apply at all times. For example, the General
Provisions states that exceedances during periods of startup, shutdown,
and malfunction are generally not considered violations of the
standards.\18\ To avoid confusion between the General Provisions and
the SSI emissions regulations, we are proposing that, in circumstances
where the requirements of the General Provisions are inconsistent with
the requirements of the SSI emissions regulations, the provisions in
the SSI regulations will control.
---------------------------------------------------------------------------

    \18\ See 40 CFR 60.8(c).
---------------------------------------------------------------------------

    In establishing the standards in this rule, EPA has taken into
account startup and shutdown periods and, for the reasons explained
below, has not established different standards for those periods.
    We are not proposing a separate emission standard for the source
category that applies during periods of startup and shutdown. Based on
the information available at this time, we believe that SSI units will
be able to meet the emission limits during periods of startup. Units we
have information on use natural gas, landfill gas, or distillate oil to
start the unit and add waste once the unit has reached combustion
temperatures. Emissions from burning natural gas, landfill gas or
distillate fuel oil are expected to generally be lower than from
burning solid wastes. Emissions during periods of shutdown

are also generally lower than emissions during normal operations
because the materials in the incinerator would be almost fully
combusted before shutdown occurs. Furthermore, the approach for
establishing MACT floors for SSI units ranked individual SSI units
based on actual performance for each pollutant and subcategory, with an
appropriate accounting of emissions variability. Because we accounted
for emissions variability, we believe we have adequately addressed any
minor variability that may potentially occur during startup or
shutdown.
    Periods of startup, normal operations, and shutdown are all
predictable and routine aspects of a source's operations. However, by
contrast, malfunction is defined as a ``sudden, infrequent, and not
reasonably preventable failure of air pollution control and monitoring
equipment, process equipment or a process to operate in a normal or
usual manner * * *'' (40 CFR 63.2). EPA has determined that
malfunctions should not be viewed as a distinct operating mode and,
therefore, any emissions that occur at such times do not need to be
factored into development of CAA section 129 standards, which, once
promulgated, apply at all times. It is reasonable to interpret section
129 as not requiring EPA to account for malfunctions in setting
emissions standards. For example, we note that section 129 uses the
concept of ``best performing'' sources in defining MACT, the level of
stringency that major source standards must meet. Applying the concept
of ``best performing'' to a source that is malfunctioning presents
significant difficulties. The goal of best performing sources is to
operate in such a way as to avoid malfunctions of their units.
    Moreover, even if malfunctions were considered a distinct operating
mode, we believe it would be impracticable to take malfunctions into
account in setting CAA section 129 standards for SSI. As noted above,
by definition, malfunctions are sudden and unexpected events, and it
would be difficult to set a standard that takes into account the myriad
different types of malfunctions that can occur across all sources in
the category. Moreover, malfunctions can vary in frequency, degree, and
duration, further complicating standard setting.
    For the SSI standards, malfunctions are required to be reported in
deviation reports. We will then review the deviation reports to
determine if the deviation is a violation of the standards.
    In the event that a source fails to comply with the applicable CAA
section 129 standards as a result of a malfunction event, EPA would
determine an appropriate response based on, among other things, the
good faith efforts of the source to minimize emissions during
malfunction periods, including preventative and corrective actions, as
well as root cause analyses to ascertain and rectify excess emissions.
EPA would also consider whether the source's failure to comply with the
CAA section 129 standard was, in fact, ``sudden, infrequent, not
reasonably preventable'' and was not instead ``caused in part by poor
maintenance or careless operation.'' \19\
---------------------------------------------------------------------------

    \19\ 40 CFR 60.2 (definition of malfunction).
---------------------------------------------------------------------------

    Moreover, EPA recognizes that even equipment that is properly
designed and maintained can fail and that such failure can sometimes
cause an exceedance of the relevant emission standard.\20\ EPA is
therefore proposing to add to the final rule an affirmative defense to
civil penalties for exceedances of emission limits that are caused by
malfunctions.\21\ We also added other regulatory provisions to specify
the elements that are necessary to establish this affirmative defense;
the source must prove by a preponderance of the evidence that it has
met all of the elements set forth in 40 CFR 60.4860 and in 40 CFR
60.5180. The criteria ensure that the affirmative defense is available
only where the event that causes an exceedance of the emission limit
meets the narrow definition of malfunction in 40 CFR 60.2 (sudden,
infrequent, not reasonable preventable and not caused by poor
maintenance and or careless operation). The criteria also are designed
to ensure that steps are taken to correct the malfunction, to minimize
emissions in accordance with section 40 CFR part 60 subpart LLLL and 40
CFR part 60 subpart MMMM and to prevent future malfunctions. In any
judicial or administrative proceeding, the Administrator may challenge
the assertion of the affirmative defense and, if the respondent has not
met its burden of proving all of the requirements in the affirmative
defense, appropriate penalties may be assessed in accordance with
section 113 of the Clean Air Act (see also 40 CFR Part 22.77).
---------------------------------------------------------------------------

    \20\ See, e.g., State Implementation Plans: Policy Regarding
Excessive Emissions During Malfunctions, Startup, and Shutdown
(Sept. 20, 1999); Policy on Excess Emissions During Startup,
Shutdown, Maintenance, and Malfunctions (Feb. 15, 1983).
    \21\ See proposed definition 40 CFR 60.4930 and 40 CFR 60.5250
(defining ``affirmative defense'' to mean, in the context of an
enforcement proceeding, a response or defense put forward by a
defendant, regarding which the defendant has the burden of proof,
and the merits of which are independently and objectively evaluated
in a judicial or administrative proceeding).
---------------------------------------------------------------------------

J. Delegation of Authority To Implement and Enforce These Provisions

    We are proposing a section on delegation of authority to clarify
which authorities can be delegated or transferred to State, local, and
tribal air pollution control agencies in this rulemaking and which are
retained by EPA. For previous rules, there has been some confusion
about what authority can be delegated to and exercised by State, local,
and tribal air pollution control agencies and what authority must be
retained by EPA. In some cases, State, local, and tribal air pollution
control agencies were making decisions, such as allowing waivers of
some provisions of this subpart, which cannot be delegated to those
agencies.
    In the proposed SSI NSPS, the authorities that would be retained by
EPA are listed in 40 CFR 60.4785 of subpart LLLL. They include
authorities that must be retained by EPA for all NSPS: Approval of
alternatives to the emission limits, approval of major alternatives to
test methods, or monitoring and approval of major alternatives to
recordkeeping and reporting. The list also specifically includes
establishment of operating limits for control devices other than those
listed in the rule per proposed 40 CFR 60.4855; and review of status
reports submitted when no qualified operators are available per
proposed 40 CFR 60.4835(b)(2). It also includes the approval of
performance test and data reduction waivers under 40 CFR 60.8(b) and
preconstruction siting analysis in proposed 40 CFR 60.4800. These
authorities may affect the stringency of the emission standards or
limitations, which can only be amended by Federal rulemaking; thus they
cannot be transferred to State, local, or tribal air pollution control
agencies. We are also including 40 CFR 60.5050 in the proposed EG to
make the provisions regarding the implementation and enforcement
authorities in both subparts LLLL and MMMM consistent. We are seeking
comment on whether these or other authorities should be retained by EPA
or delegated to State, local, or tribal air pollution control agencies.

K. State Plans

    We are proposing regulatory language to clarify how states and
eligible tribes can fulfill their obligation under CAA section 129
(b)(2) in lieu of submitting a State plan for review and approval. We
are adding proposed 40 CFR 60.5045 that will clarify how states and
eligible tribes can fulfill the obligation under

CAA section 129 (b)(2) by submitting an acceptable, as specified in 40
CFR 60.2541, written request for delegation of the Federal plan.
Proposed 40 CFR 60.5045 lists specific requirements, such as a
demonstration of adequate resources and legal authority to implement
and enforce the Federal plan, that must be met in order to receive
delegation of the Federal plan. We are seeking comment on this
provision.

V. Impacts of the Proposed Action

A. Impacts of the Proposed Action for Existing Units

1. What are the primary air impacts?
    We have estimated the potential emission reductions that may be
realized through implementation of the proposed emission limits. Table
12 of this preamble summarizes the emission reductions for MACT
compliance for each pollutant. The analysis is documented in the
memorandum ``Analysis of Beyond the Maximum Achievable Control
Technology (MACT) Floor Controls for Existing SSI Units.''

  Table 12--Projected Emission Reductions for Existing SSI Units If All
            Entities Comply With the Proposed Emission Limits
------------------------------------------------------------------------
                                      Reductions achieved
                                    through meeting MACT by
                                       subcategory (TPY)        Total
            Pollutant             --------------------------  reductions
                                    Fluidized     Multiple      (TPY)
                                       bed         hearth
------------------------------------------------------------------------
Cd...............................       0.0010          1.4          1.4
CDD/CDF TEQ......................    0.0000065    0.0000013    0.0000078
CDD/CDF TMB......................     0.000079     0.000020     0.000099
CO...............................            0            0            0
HCl..............................          1.5           92           93
Hg...............................        0.058          2.7          2.7
NOX..............................            0          4.3          4.3
Pb...............................       0.0053          2.6          2.6
PM...............................           41          278          319
SO2..............................           60        2,100        2,200
                                  --------------------------------------
    Total........................          102        2,510        2,610
------------------------------------------------------------------------

2. What are the water and solid waste impacts?
    We anticipate affected sources would need to apply additional
controls to meet the proposed emission limits. These controls may
utilize water, such as wet scrubbers, which would need to be treated.
We estimate an annual requirement of 346 million gallons per year of
additional wastewater would be generated as a result of operating
additional controls or increased sorbents.
    Likewise, the addition of PM controls or improvements to controls
already in place would increase the amount of particulate collected
that would require disposal. Furthermore, activated carbon injection
may be utilized by some sources, which would result in additional solid
waste needing disposal. The annual amounts of solid waste that would
require disposal are anticipated to be approximately 364 TPY from PM
capture and 11,400 TPY from activated carbon injection. The analysis is
documented in the memorandum ``Secondary Impacts for the Sewage Sludge
Incineration Source Category.''
3. What are the energy impacts?
    The energy impacts associated with meeting the proposed emission
limits would consist primarily of additional electricity needs to run
added or improved air pollution control devices. For example, increased
scrubber pump horsepower may cause slight increases in electricity
consumption; sorbent injection controls would likewise require
electricity to power pumps and motors. We anticipate that an additional
33,800 megawatt-hours per year would be required for the additional and
improved control devices. The analysis is documented in the memorandum
``Secondary Impacts for the Sewage Sludge Incineration Source
Category.''
4. What are the secondary air impacts?
    For SSI units adding controls to meet the proposed emission limits,
we anticipate very minor secondary air impacts. The combustion of fuel
needed to generate additional electricity would yield slight increases
in emissions, including NOX, CO, PM and SO2 and
an increase in CO2 emissions. Since NOX and
SO2 are covered by capped emissions trading programs, and
methodological limitations prevent us from quantifying the change in CO
and PM, we do not estimate an increase in secondary air impacts for
this rule from additional electricity demand.
5. What are the cost and economic impacts?
    We have estimated compliance costs for all existing units to add
the necessary controls, monitoring equipment, inspections,
recordkeeping, and reporting requirements to comply with Option 2
(i.e., the proposed SSI standards). Based on this analysis, we
anticipate an overall total capital investment of $225 million with an
associated total annualized cost of $105 million, in 2008 dollars (and
using a discount rate of 7 percent), as shown in Table 13 of this
preamble. We anticipate that owner/operators will need to install 1 or
more air pollution control devices for 214 of the 218 affected units to
meet the proposed emission limits. We are requesting comment on whether
there are space constraints at wastewater treatment facilities that
would affect the feasibility and cost of installing air pollution
control devices. The analysis is documented in the memorandum
``Analysis of Beyond the Maximum Achievable Control Technology (MACT)
Floor Controls for Existing SSI Units.''

 Table 13--Summary of Costs for Existing SSI If All Entities Comply With
                        Proposed Emission Limits
                           [Millions of 2008$]
------------------------------------------------------------------------
                                                        Annualized cost
            Subcategory              Capital cost ($     ($ million/yr)
                                         million)             \a\
------------------------------------------------------------------------
Fluidized Bed.....................               86.7               32.3
Multiple Hearth...................              138.0               72.7
                                   -------------------------------------
    Total.........................              224.7              105.0
------------------------------------------------------------------------
\a\ Calculated using a discount factor of 7 percent.

    Analysis of Alternative Sewage Sludge Disposal. We have also
evaluated the possibility that existing SSI owners would dispose of
sewage sludge through alternative methods rather than incineration,
such as landfilling, land application, or sending sewage sludge to
another SSI unit. The alternative method we analyzed was landfilling,
which is generally more expensive than land application, but would
provide a more conservative estimate of the cost of alternative
disposal.
    We conducted this analysis by determining the cost of landfilling
and then subtracting the existing cost of operating the SSI unit
(because this cost would no longer be incurred). The cost of
landfilling sewage sludge included landfill tipping fees as well as
transportation costs. The cost of storing dewatered sewage sludge on-
site for up to four days was also included in the landfilling cost.
Sewage sludge incineration unit operating costs were obtained from ICR
questionnaires sent to 9 facilities. These costs are discussed in more
detail in the memorandum ``Cost and Emission Reduction of the MACT
Floor Level of Control,'' which is in the SSI docket. We request
comment on the assumptions and cost estimates used for the landfilling
option. The results of the analysis shows that, for most facilities,
landfilling sewage sludge is a more economically advantageous disposal
option than continuing to operate their SSI unit. It was assumed that
smaller sources presented with the option of applying MACT controls or
landfilling would select landfilling because the analysis shows a cost
savings, even when not considering the additional cost of MACT
controls. If the cost of the MACT controls were also included, it would
be even more advantageous to landfill.
    However, there are several uncertainties with the analysis that may
significantly impact the results. These include:

     The operating cost information was based on only the 9
ICR respondents, which are larger units. Smaller units may have
lower or different operating costs that are not captured in the
operating cost factors or different capacity utilizations or
operating hours.
     For some SSI units, the nearest landfill accepting
sewage sludge may be farther than assumed in the analysis.

    To confirm the results of the analysis, we contacted 9 owners of
wastewater treatment facilities that would be considered small
entities, that is, the population of the municipalities or regional
authorities that own the facility were less than or equal to 50,000
people. We also reviewed company Web sites for other small entities to
find the status of the SSI units. The results of the data collection
showed that the majority of small entities have shut down their SSI
unit and are either land applying or landfilling. Others are planning
on landfilling in the future. The data collection, as well as the cost
estimate for the landfilling option is discussed in the memorandum,
``Cost and Emission Reduction of the MACT Floor Level of Control.''
    While we are able to confirm this analysis for smaller entities, we
were unable to conduct it for larger entities. We also believe that
facilities that use larger SSI units may have more difficulty in
landfilling sewage sludge due to potential capacity issues at
landfills. This may result in higher tipping fees and transportation
costs to find landfills with available capacity. As a result of these
concerns, we do not believe that larger entities would necessarily find
it more advantageous to landfill sewage sludge.
    We believe that smaller entities (i.e., with populations less than
50,000 people) are likely to landfill. This would result in lowered
costs of compliance with the MACT for existing sources, as well as
minor changes in the emission reductions achieved. We also believe that
based on our estimates there will be no increased cost to small
entities using this alternative option. However, it does not change the
result that option 2 (MACT floor levels plus meeting the beyond-the-
floor Hg limit of 0.02 mg/dscm) would be appropriate due to the
significant Hg emissions reductions that would still occur for larger
sources. The analysis is documented in the memorandum ``Analysis of
Beyond the Maximum Achievable Control Technology (MACT) Floor Controls
for Existing SSI Units.''
    Table 14 of this preamble summarizes the costs associated with
small entities landfilling and large entities complying with the MACT
control levels. For the option selected, we estimate that 196 (90%) of
the affected units will need to install 1 or more air pollution control
devices.

   Table 14--Summary of Costs for Existing SSI Units If Large Entities
   Comply With the Proposed Emission Limits and Small Entities Utilize
                  Alternative Disposal (i.e., Landfill)
                           [Millions of 2008$]
------------------------------------------------------------------------
                                                         Annualized cost
            Subcategory               Capital cost ($    ($ million/yr)
                                          million)             \a\
------------------------------------------------------------------------
Fluidized Bed......................               70.0              26.2
Multiple Hearth....................              130.9              62.5
                                    ------------------------------------
    Total..........................              200.9              88.7
------------------------------------------------------------------------
\a\ Calculated using a discount factor of 7 percent.

    We have estimated the potential emission reductions that may be
realized through implementation of the proposed emission limits. For
the case where small entities choose to landfill, some emission
reductions are offset by emissions resulting from hauling, landfill gas
generation, and flaring. The estimation of these emissions is
documented in the memorandum ``Cost and Emission Reduction of the MACT
Floor Level of Control.'' Emissions from landfilling are subtracted
from the total reductions resulting from units complying or shutting
down. Table 15 of this preamble summarizes the net emission reductions
for each pollutant.

 Table 15--Projected Emission Reductions for Existing SSI If Large Entities Comply With the Emission Limits and
                          Small Entities Utilize Alternative Disposal (i.e., Landfill)
----------------------------------------------------------------------------------------------------------------
                                                    Reductions achieved
                                                  through meeting MACT by   Emissions    Emissions
                                                     subcategory (TPY)         from         from        Total
                   Pollutant                    --------------------------   hauling      landfill    reductions
                                                  Fluidized     Multiple      (TPY)      and flare      (TPY)
                                                     bed         hearth                    (TPY)
----------------------------------------------------------------------------------------------------------------
Cd.............................................       0.0028         1.55            0            0          1.6
CDD/CDF TEQ....................................    0.0000065    0.0000013            0            0    0.0000078
CDD/CDF TMB....................................     0.000080     0.000020            0            0     0.000099
CO.............................................           19        3,100          6.0          240        2,900
HCl............................................          1.8           95            0         0.38           96
Hg.............................................        0.061          2.7            0   0.00000023          2.8
Pb.............................................         0.15          3.0            0            0          3.0
PM.............................................           43          350          1.3         0.90          390
NOX............................................         53.0          794           22          2.1          823
SO2............................................           77        2,200        0.052         0.75        2,300
                                                ----------------------------------------------------------------
    Total......................................          190        6,410           30          244        6,330
----------------------------------------------------------------------------------------------------------------

    With respect to water and solid waste impacts in the case where
large entities comply and small entities landfill, we estimate an
annual requirement of 319 million gallons per year of additional
wastewater would be generated as a result of operating additional
controls or increased sorbents for the units that add controls to
comply with the rule. Additionally, the annual amounts of solid waste
that would require disposal are anticipated to be approximately 324 TPY
from PM capture and 10,000 TPY from activated carbon injection. The
largest impact on solid waste, however, would come from small entities
choosing to discontinue the use of their SSI and instead send the waste
to a landfill. We estimate approximately 359,000 TPY of waste would be
diverted to landfills. The analysis is documented in the memorandum
``Secondary Impacts for the Sewage Sludge Incineration Source
Category.'' We request comment on whether landfilling is more
advantageous environmentally than the incineration of sewage sludge.
    As described in section V.A.3 of this preamble, the energy impacts
associated with meeting the proposed emission limits would consist
primarily of additional electricity needs to run added or improved air
pollution control devices. For the scenario where only large entities
comply, we anticipate that an additional 29,200 megawatt-hours per year
would be required for the additional and improved control devices. The
analysis is documented in the memorandum ``Secondary Impacts for the
Sewage Sludge Incineration Source Category.''
    For SSI units adding controls to meet the proposed emission limits,
we anticipate very minor secondary air impacts. As previously noted, in
the case where small entities choose to landfill, there would be
additional air impacts due to emissions generated by trucks hauling
waste and emissions from landfill gas and flaring. Table 16 of this
preamble summarizes the estimated results.

  Table 16--Summary of Secondary Impacts for Existing Sources If Large
  Entities Comply With the Proposed Emission Limits and Small Entities
              Utilize Alternative Disposal (i.e., Landfill)
------------------------------------------------------------------------
                                Secondary air impacts from
                                  diverting SSI waste to
                                      landfills (TPY)           Total
           Pollutant           ----------------------------   secondary
                                   Waste-                      impacts
                                   hauling    Landfill gas    (ton/yr)
                                  vehicles      and flare
------------------------------------------------------------------------
Cd............................            --            --            --
CDD/CDF, TEQ..................            --            --            --
CO............................          6.03         240.2        246.23
HCl...........................            --          0.38          0.38
Hg............................            --   0.000000233   0.000000233
NOX...........................         21.84          2.11         23.95
Pb............................            --            --            --
PM............................          1.30          0.90          2.20
PM2.5.........................          1.12            --          1.12
SO2...........................          0.05          0.75          0.80
                               -----------------------------------------

    Total.....................         30.35         244.3        274.65
------------------------------------------------------------------------

    Because the proposed regulatory option affects governmental
entities (96 of the 97 owners are governmental entities) providing
services not provided in a market, the economic analysis focused on the
comparison of control cost to total governmental revenue. (See Table 17
of this preamble.) Table 17 sets forth the overall costs to large and
small municipalities and shows that there will be no increased costs to
small municipalities and a net, relatively small, increase for large
municipalities.

Table 17--Revenue Tests for Government Entities If Large Entities Comply
With the Emission Limits and Small Entities Utilize Alternative Disposal
                            (i.e., Landfill)
------------------------------------------------------------------------
     Sample statistic for cost-revenue-ratios         Small      Large
------------------------------------------------------------------------
Mean..............................................      -0.6%       0.2%
Median............................................      -0.2%       0.1%
Minimum...........................................      -2.6%       0.0%
Maximum...........................................       0.7%       1.0%
Number of Entities................................         18         79
Number of Entities >1%............................          0          0
Number of Entities >3%............................          0          0
------------------------------------------------------------------------
None of the entities has cost-revenue-ratios greater than 1 percent.

B. Impacts of the Proposed Action for New Units

    As discussed in section IV.C.2 of this preamble, based on trends of
SSI units constructed and replaced, technical advantages of FB
incinerators, and information provided by the industry on likely units
constructed, we believe that new SSI units constructed are likely to be
FB incinerators.
1. What are the primary air impacts?
    We have estimated the potential emission reductions that may be
realized through implementation of the proposed emission limits on 2
new FB incinerators potentially being constructed in the next 5 years.
Table 18 of this preamble summarizes the emission reductions for MACT
compliance for each pollutant. The analysis is documented in the
memorandum ``Estimation of Impacts for New Units Constructed Within 5
Years After Promulgation of the SSI NSPS.''

 Table 18--Emission Reductions for 2 New SSI Units (i.e., Fluidized Bed
                        Incinerators) Constructed
------------------------------------------------------------------------
                                                               Emission
                         Pollutant                            reduction
                                                                (TPY)
------------------------------------------------------------------------
Cd.........................................................      0.00047
CDD/CDF, TEQ...............................................   0.00000038
CDD/CDF, TMB...............................................    0.0000044
CO.........................................................        3.022
HCl........................................................        0.033
Hg.........................................................       0.0036
NOX........................................................         1.07
Pb.........................................................       0.0031
PM.........................................................         2.43
PM2.5......................................................         2.76
SO2........................................................         1.01
                                                            ------------
Total......................................................        10.33
------------------------------------------------------------------------

2. What are the water and solid waste impacts?
    We anticipate affected sources would need to apply controls in
addition to what they would have planned to include in the absence of
this rule to meet the proposed emission limits. These controls may
utilize water, such as wet scrubbers, which would need to be treated.
We estimate an annual requirement of 18.2 million gallons per year of
additional wastewater would be generated as a result of operating
additional controls or increased sorbents for the 2 new units expected
to come online in the next 5 years. The analysis is documented in the
memorandum ``Analysis of New Units for the Sewage Sludge Incineration
Source Category Analysis of Secondary Impacts for the Sewage Sludge
Incineration Source Category.''
    Likewise, the application of PM controls results in particulate
collected that would require disposal. Furthermore, activated carbon
injection may be used by some sources, which would result in solid
waste needing disposal. The annual amounts of solid waste that would
require disposal are anticipated to be approximately 4 TPY from PM
capture and 97 TPY from activated carbon injection for the 2 units.
3. What are the energy impacts?
    The energy impacts associated with meeting the proposed emission
limits would consist primarily of additional electricity needs to run
added or improved air pollution control devices. For example, increased
scrubber pump horsepower may cause slight increases in electricity
consumption. Sorbent injection controls would likewise require
electricity to power pumps and motors. By our estimate, we anticipate
that an additional 1,350 megawatt-hours

per year would be required for the additional and improved control
devices for the 2 new units modeled to come online in the next 5 years.
The analysis is documented in the memorandum ``Analysis of Secondary
Impacts for the Sewage Sludge Incineration Source Category Analysis of
New Units for the Sewage Sludge Incineration Source Category.''
4. What are the secondary air impacts?
    For SSI units adding controls to meet the proposed emission limits,
we anticipate very minor secondary air impacts. The analysis is
documented in the memorandum ``Analysis of Secondary Impacts for the
Sewage Sludge Incineration Source Category.''
5. What are the cost impacts?
    We have estimated compliance costs for new SSI units coming online
in the next 5 years. This analysis is based on a model plant, the
assumption that 2 new units will come online and will add the necessary
controls, monitoring equipment, inspections, recordkeeping, and
reporting requirements to comply with the proposed SSI standards. Based
on this analysis, we anticipate an overall total capital investment of
$7.81 million (2008$) with an associated total annualized cost of $2.70
million (2008$ and using a 7 percent discount rate). This analysis
assumes that new SSI units constructed are only FB incinerators, as
discussed in section IV.C.2 of this preamble.

C. Benefits of the Proposed NSPS and EG

    We estimate the monetized benefits of this proposed regulatory
action to be $130 million to $320 million (2008$, 3 percent discount
rate) in the implementation year (2015). The monetized benefits of the
proposed regulatory action at a 7 percent discount rate are $120
million to $290 million (2008$). These estimates reflect energy
disbenefits valued at $0.5 million. Using alternate relationships
between PM2.5 and premature mortality supplied by experts,
higher and lower benefits estimates are plausible, but most of the
expert-based estimates fall between these 2 estimates.\22\ A summary of
the monetized benefits estimates at discount rates of 3 percent and 7
percent is in Table 19 of this preamble.
---------------------------------------------------------------------------

    \22\ Roman et al., 2008. Expert Judgment Assessment of the
Mortality Impact of Changes in Ambient Fine Particulate Matter in
the U.S. Environ. Sci. Technol., 42, 7, 2268-2274.

          Table 19--Summary of the Monetized Benefits Estimates for New and Existing SSI Units in 2015
                                             [Millions of 2008$] \1\
----------------------------------------------------------------------------------------------------------------
                                            Estimated
                                            emission     Total  monetized  benefits   Total  monetized  benefits
               Pollutant                   reductions        (3% discount rate)           (7% discount rate)
                                              (TPY)
----------------------------------------------------------------------------------------------------------------
PM2.5..................................             254  $58 to $140...............  $52 to $130.
----------------------------------------------------------------------------------------------------------------
PM2.5 Precursors:
    SO2................................           2,298  $68 to $170...............  $61 to $150.
    NOX................................             824  $4.0 to $9.8..............  $3.6 to $8.8.
                                        ------------------------------------------------------------------------
    Total..............................  ..............  $130 to $320..............  $120 to $290.
----------------------------------------------------------------------------------------------------------------
\1\ All estimates are for the implementation year (2015) and are rounded to 2 significant figures so numbers may
  not sum across rows. All fine particles are assumed to have equivalent health effects, but the benefit-per-ton
  estimates vary between precursors because each ton of precursor reduced has a different propensity to form
  PM2.5. Benefits from reducing HAP are not included. These results include 2 new FB incinerators anticipated to
  come online by 2015, and the assumption that some small entities will landfill. These estimates do not include
  the energy disbenefits valued at $0.5 million, but the rounded totals do not change. CO2-related disbenefits
  were calculated using the social cost of carbon, which is discussed further in the RIA.

    These benefits estimates represent the total monetized human health
benefits for populations exposed to less PM2.5 in 2015 from
controls installed to reduce air pollutants in order to meet these
standards. These estimates are calculated as the sum of the monetized
value of avoided premature mortality and morbidity associated with
reducing a ton of PM2.5 and PM2.5 precursor
emissions. To estimate human health benefits derived from reducing
PM2.5 and PM2.5 precursor emissions, we utilized
the general approach and methodology laid out in Fann et al.
(2009).\23\
---------------------------------------------------------------------------

    \23\ Fann, N., C.M. Fulcher, B.J. Hubbell. 2009. ``The influence
of location, source, and emission type in estimates of the human
health benefits of reducing a ton of air pollution.'' Air Qual Atmos
Health. (2009) 2:169-176.
---------------------------------------------------------------------------

    To generate the benefit-per-ton estimates, we used a model to
convert emissions of direct PM2.5 and PM2.5
precursors into changes in ambient PM2.5 levels and another
model to estimate the changes in human health associated with that
change in air quality. Finally, the monetized health benefits were
divided by the emission reductions to create the benefit-per-ton
estimates. These models assume that all fine particles, regardless of
their chemical composition, are equally potent in causing premature
mortality because there is no clear scientific evidence that would
support the development of differential effects estimates by particle
type. Directly emitted PM, SO2, and NOX are the
primary PM2.5 precursors affected by this rule. Even though
we assume that all fine particles have equivalent health effects, the
benefit-per-ton estimates vary between precursors because each ton of
precursor reduced has a different propensity to form PM2.5.
For example, SO2 has a lower benefit-per-ton estimate than
direct PM2.5 because it does not form as much
PM2.5, thus the exposure would be lower, and the monetized
health benefits would be lower.
    For context, it is important to note that the magnitude of the PM
benefits is largely driven by the concentration response function for
premature mortality. Experts have advised EPA to consider a variety of
assumptions, including estimates based on both empirical
(epidemiological) studies and judgments elicited from scientific
experts, to characterize the uncertainty in the relationship between
PM2.5 concentrations and premature mortality. For this
proposed rule, we cite two key

empirical studies, one based on the American Cancer Society cohort
study \24\ and the extended Six Cities cohort study.\25\ In the RIA for
this proposed rule, which is available in the docket, we also include
benefits estimates derived from expert judgments and other assumptions.
---------------------------------------------------------------------------

    \24\ Pope et al., 2002. ``Lung Cancer, Cardiopulmonary
Mortality, and Long-term Exposure to Fine Particulate Air
Pollution.'' Journal of the American Medical Association. 287:1132-
1141.
    \25\ Laden et al., 2006. ``Reduction in Fine Particulate Air
Pollution and Mortality.'' American Journal of Respiratory and
Critical Care Medicine. 173: 667-672.
---------------------------------------------------------------------------

    EPA strives to use the best available science to support our
benefits analyses. We recognize that interpretation of the science
regarding air pollution and health is dynamic and evolving. After
reviewing the scientific literature and recent scientific advice, we
have determined that the no-threshold model is the most appropriate
model for assessing the mortality benefits associated with reducing
PM2.5 exposure. Consistent with this recent advice, we are
replacing the previous threshold sensitivity analysis with a new
``LML'' assessment. While an LML assessment provides some insight into
the level of uncertainty in the estimated PM mortality benefits, EPA
does not view the LML as a threshold and continues to quantify PM-
related mortality impacts using a full range of modeled air quality
concentrations.
    Most of the estimated PM-related benefits in this rule would accrue
to populations exposed to higher levels of PM2.5. Using the
Pope, et al., (2002) study, 85 percent of the population is exposed at
or above the LML of 7.5 [mu]g/m\3\. Using the Laden, et al., (2006)
study, 40 percent of the population is exposed above the LML of 10
[mu]g/m\3\. It is important to emphasize that we have high confidence
in PM2.5-related effects down to the lowest LML of the major
cohort studies. This fact is important, because as we estimate PM-
related mortality among populations exposed to levels of
PM2.5 that are successively lower, our confidence in the
results diminishes. However, our analysis shows that the great majority
of the impacts occur at higher exposures.
    This analysis does not include the type of detailed uncertainty
assessment found in the 2006 PM2.5 NAAQS RIA because we lack
the necessary air quality input and monitoring data to run the benefits
model. In addition, we have not conducted any air quality modeling for
this rule. The 2006 PM2.5 NAAQS benefits analysis \26\
provides an indication of the sensitivity of our results to various
assumptions.
---------------------------------------------------------------------------

    \26\ U.S. Environmental Protection Agency, 2006. Final
Regulatory Impact Analysis: PM2.5 NAAQS. Prepared by
Office of Air and Radiation. October. Available on the Internet at
http://www.epa.gov/ttn/ecas/ria.html.
---------------------------------------------------------------------------

    It should be emphasized that the monetized benefits estimates
provided above do not include benefits from several important benefit
categories, including reducing other air pollutants, ecosystem effects,
and visibility impairment. The benefits from reducing HAP have not been
monetized in this analysis, including reducing 2,900 tons of CO, 96
tons of HCl, 3.0 tons of Pb, 1.6 tons of Cd, 5,500 pounds of Hg and 78
grams of total CDD/CDF each year. Although we do not have sufficient
information or modeling available to provide monetized estimates for
this rulemaking, we include a qualitative assessment of the health
effects of these air pollutants in the RIA for this proposed rule,
which is available in the docket.
    In addition, the monetized benefits estimates provided in Table 19
do not reflect the disbenefits associated with increased electricity
and fuel consumption to operate the control devices. We estimate that
the increases in emissions of CO2 would have disbenefits
valued at $0.5 million for the proposed option assuming that small
entities landfill at a 3 percent discount rate. CO2-related
disbenefits were calculated using the social cost of carbon, which is
discussed further in the RIA. However, these disbenefits do not change
the rounded total monetized benefits of the proposed option, which are
still $130 million to $320 million and $120 million to $290 million, at
discount rates of 3 percent and 7 percent, respectively.
    The social costs of this proposed rulemaking are estimated to be
$92 million (2008$) in the implementation year and the monetized
benefits including energy disbenefits are $130 million to $320 million
(2008$, 3 percent discount rate) for that same year. The monetized
benefits including energy disbenefits at a 7 percent discount rate are
$120 million to $290 million (2008$). Thus, net benefits of this
rulemaking including energy disbenefits estimated at $37 million to
$220 million (2008$, 3 percent discount rate) and $26 million to $190
million (2008$, 7 percent discount rate).

VI. Relationship of the Proposed Action to CAA Sections 112(c)(3) and
112(k)(3)(B)(ii)

    Clean Air Act sections 112(c)(3) and (k)(3)(B)(ii) instruct EPA to
identify and list area source categories representing at least 90
percent of the emissions of the 30 ``listed'' HAP (64 FR 38706, July
19, 1999), that are, or will be, subject to standards under section
112(d) of the CAA. The 30 HAP are the result of emissions from area
sources that pose the greatest threat to public health in the largest
number of urban areas. Under the provisions of section 112(c)(3) and
(k)(3)(B)(ii) of the CAA, SSI was added to the inventory. Each of the
source categories added, including SSI, contributes a certain
percentage of the total area source emissions for at least 1 of the 30
area source HAP and makes progress towards meeting our requirement to
address 90 percent of the emissions of each of the 30 area source HAP.
    As required by the statute, the CAA section 129 SSI standards
include numeric emission limits for the 9 pollutants specified in
section 129(a)(4) and opacity. The combination of wastewater
pretreatment, good combustion practices and add-on air pollution
control devices (e.g., FF, scrubbers, activated carbon injection,
afterburners) effectively reduces emissions of the pollutants for which
emission limits are required under CAA section 129: Cd, CO, CDD/CDF,
HCl, Hg, Pb, NOX, PM and SO2.
    Although, CAA section 129 standards for SSI will not set separate
specific numerical emission limits for sections 112(c)(3) and
(k)(3)(B)(ii) urban air HAP, the SSI standards will result in
substantial reductions of 7-PAH, Cr, Mn, Ni, and PCB. These additional
emission reductions are due to co-control of pollutants by the same air
pollution control devices used to comply with the CAA section 129 SSI
standard. Air pollution control devices are necessary to comply with
the requirements of the SSI NSPS and EG. Add-on air pollution control
devices to control PM will also reduce emissions of compounds that
coalesce to form on PM (e.g., Mn, Ni, Cr, etc.). The addition of any
post-combustion device to control organics such as CO and CDD/CDF will
also reduce emissions for any byproducts of incomplete combustion such
as additional organic pollutants (e.g., 7-PAH and PCB). The addition of
wet scrubbers will also reduce emissions of compounds that are water
soluble. Additionally, the NSPS emission limits will promote the
construction of new FB incinerators rather than MH incinerators.
Fluidized bed incinerators have significantly lower emissions of all
organic compounds and NOX.
    While the proposed rule does not identify specific numerical
emission limits for 7-PAH, Cr, Mn, Ni and PCB,

emissions of those pollutants are for the reasons noted above,
nonetheless, subject to regulation for the purposes of section
112(c)(3) and (k)(3)(B)(ii) of the CAA. In lieu of establishing
numerical emission limits for pollutants such as PCB and 7-PAH, CAA
section 129 (a)(4) allows EPA to regulate surrogate substances. While
we have not identified specific numerical limits for 7-PAH or PCB, we
believe CO serves as an effective surrogate of those pollutants,
because CO, like 7-PAH and PCB, is formed as a byproduct of combustion.
We believe that CDD/CDF also serve as an effective surrogate for PCB,
because the compounds act similarly and, thus, are expected to be
controlled similarly using SSI emission control devices (e.g., wet
scrubbers, FF, activated carbon injection).

VII. Relationship of the Proposed Action to Other SSI Rules for the Use
or Disposal of Sewage Sludge

    Under authority of section 405(d) and (e) of the CWA, as amended 33
U.S.C.A. 1251, (et seq.), EPA promulgated regulations on February 19,
1993, at 40 CFR part 503 designed to protect public health and the
environment from any reasonably anticipated adverse effects of certain
pollutants that may be present in sewage sludge. The part 503
regulations establish requirements for the final use and disposal of
sewage sludge when: (1) The sludge is applied to the land for a
beneficial use (e.g., for use in home gardens); (2) the sludge is
disposed on land by placing it on surface disposal sites; and (3) the
sewage sludge is incinerated. The standards apply to POTW that generate
or treat domestic sewage sludge, as well as to any person who uses or
disposes of sewage sludge from such treatment works.
    The part 503 requirements for firing sewage sludge in a SSI are in
subpart E of the regulations. Subpart E includes general requirements;
pollutant limits; operational standards; management practices; and
monitoring, recordkeeping, and reporting requirements.
    These part 503 regulations require that SSI meet the National
Emission Standards for Beryllium and Hg in subparts C and E,
respectively, of 40 CFR part 61. The regulations also require that the
allowable concentration of 5 other inorganic pollutants be calculated
using equations in the regulation. The inorganic pollutants included
are Pb, As, Cd, Cr, and Ni. The terms in the equations must be
determined on a case-by-case basis, except for the risk-specific
concentration for the inhalation exposure pathway to protect
individuals when these pollutants are inhaled. The site-specific
variables for the equations (incinerator type, dispersion factor,
control efficiency, feed rate, and stack height) must be used to
calculate allowable daily concentrations of As, Cd, Cr, Pb and Ni in
the sewage sludge fed to the incinerator.
    Also included in subpart E is an operational standard for THC. The
value for THC in the final part 503 regulation cannot be exceeded in
the exit gas from the SSI stack. Management practices and frequency of
monitoring, recordkeeping, and reporting requirements are also included
in this subpart.
    Under today's proposed rule, EPA is establishing limits for 3 of
the inorganic pollutants covered by the current part 503 regulations
(Cd, Pb and Hg) and the following 7 additional pollutants: HCl, CO,
opacity, NOX, SO2, PM, and total CDD/CDF. Besides
the pollutants covered here, there are other differences between the
part 503 regulations and this proposed rule. The emission limits for
inorganic pollutants under part 503 are risk-based numbers rather than
technology-based. Also, part 503 does not distinguish between new and
existing units or between incinerator types (i.e., MH or FB
incinerator) for setting emission limits since emission limits are
based on risks to a highly exposed individual.
    Because both part 503 and this proposed rule cover the same
universe of facilities, there are certain issues that arise in terms of
potential impacts to current SSI facilities. First, we expect that the
regulation of sewage sludge under CAA section 129 under the proposed
rule would result in stricter emission standards than under the current
CWA rule. Consequently, a potential impact of this rule is that some of
the estimated 112 facilities that operate SSI as the primary means of
disposal could discontinue this practice and would instead landfill
their sewage sludge (see earlier discussion in section V of this
preamble on the analysis of alternative sewage sludge disposal).
Second, one must consider the available capacity of surface disposal
sites to receive additional sewage sludge and the potential for added
costs if the use of SSI is discontinued. Third, SSI would be subject to
2 different sets of requirements (numeric standards, operational
standards, monitoring, recordkeeping, and reporting) under the 2
different statutes if the proposed rule is implemented, creating an
additional burden to these facilities unless alternative regulatory
approaches are implemented. EPA plans to evaluate the requirements
under both statutes once this proposed rule is finalized to determine
what changes, if any, should be made to the part 503 regulations. EPA
requests comments on other potential impacts of this proposed rule on
SSI.

VIII. Statutory and Executive Order Reviews

A. Executive Order 12866: Regulatory Planning and Review

    Under section 3(f)(1) of Executive Order 12866 (58 FR 51735,
October 4, 1993), this action is an ``economically significant
regulatory action'' because it is likely to have an annual effect on
the economy of $100 million or more. Accordingly, EPA submitted this
action to the 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. In addition, EPA prepared a RIA of the
potential costs and benefits associated with this action.
    When estimating the PM2.5- and ozone-related human
health benefits and compliance costs in Table 20 below, EPA applied
methods and assumptions consistent with the State-of-the-science for
human health impact assessment, economics, and air quality analysis.
EPA applied its best professional judgment in performing this analysis
and believes that these estimates provide a reasonable indication of
the expected benefits and costs to the nation of this rule. The RIA
available in the docket describes in detail the empirical basis for
EPA's assumptions and characterizes the various sources of
uncertainties affecting the estimates below.
    When characterizing uncertainty in the PM-mortality relationship,
EPA has historically presented a sensitivity analysis applying
alternate assumed thresholds in the PM concentration-response
relationship. In its synthesis of the current State of the PM science,
EPA's ``2009 Integrated Science Assessment (ISA) for Particulate
Matter'' concluded that a no-threshold log-linear model most adequately
portrays the PM-mortality concentration-response relationship. In the
RIA accompanying this rule, rather than segmenting out impacts
predicted to be associated levels above and below a `bright line'
threshold, EPA includes a ``LML'' that illustrates the increasing
uncertainty that characterizes exposure attributed to levels of
PM2.5 below the LML for each study. Figures provided in the
RIA show the distribution of baseline exposure to PM2.5, as
well as the lowest air quality levels measured in each of the
epidemiology cohort studies. This

information provides a context for considering the likely portion of
PM-related mortality benefits occurring above or below the LML of each
study; in general, our confidence in the size of the estimated
reduction PM2.5-related premature mortality diminishes as
baseline concentrations of PM2.5 are lowered. Using the
Pope, et al., (2002) study, 85 percent of the population is exposed to
annual mean PM2.5 levels at or above the LML of 7.5 [mu]g/
m\3\. Using the Laden, et al., (2006) study, 40 percent of the
population is exposed above the LML of 10 [mu]g/m\3\. While the LML
analysis provides some insight into the level of uncertainty in the
estimated PM mortality benefits, EPA does not view the LML as a
threshold and continues to quantify PM-related mortality impacts using
a full range of modeled air quality concentrations.
    A summary of the monetized benefits, social costs and net benefits
for the proposed option, as well as a less stringent option and more
stringent option, at discount rates of 3 percent and 7 percent is in
Table 18 of this preamble.

    Table 20--Summary of the Monetized Benefits, Social Costs and Net
             Benefits for New and Existing SSI Units in 2015
                         [Millions of 2008$] \1\
------------------------------------------------------------------------
                                   3% Discount rate    7% Discount rate
------------------------------------------------------------------------
 Proposed: Option 2 MACT Floor and Beyond-the-Floor Controls for Hg and
                                 CDD/CDF
------------------------------------------------------------------------
Total Monetized Benefits \2\....  $120 to $310......  $110 to $280.
Total Social Costs \3\..........  $92...............  $92.
Net Benefits....................  $33 to $220.......  $23 to $190.
------------------------------------------------------------------------
Non-monetized Benefits..........  2,900 tons of CO.
                                  96 tons of HCl.
                                  5,500 pounds of Hg.
                                  1.6 tons of Cd.
                                  3.0 tons of Pb.
                                  90 grams of CDD/CDF.
                                  Health effects from NOX and SO2
                                   exposure.
                                  Ecosystem effects.
                                  Visibility impairment.
------------------------------------------------------------------------
                           Option 1 MACT Floor
------------------------------------------------------------------------
Total Monetized Benefits \2\....  $120 to $310......  $110 to $280.
Total Social Costs \3\..........  $63...............  $63.
Net Benefits....................  $62 to $240.......  $52 to $220.
------------------------------------------------------------------------
Non-monetized Benefits..........  2,900 tons of CO.
                                  96 tons of HCl.
                                  820 pounds of Hg.
                                  1.6 tons of Cd.
                                  3.0 tons of Pb.
                                  74 grams of CDD/CDF.
                                  Health effects from NOX and SO2
                                   exposure.
                                  Ecosystem effects.
                                  Visibility impairment.
------------------------------------------------------------------------
 Option 3 MACT Floor, Beyond-the-Floor Controls for Hg and CDD/CDF, and
                    Beyond-the-Floor Controls for CO
------------------------------------------------------------------------
Total Monetized Benefits \2\....  $120 to $300......  $110 to $280.
Total Social Costs \3\..........  $132..............  $132.
Net Benefits....................  -$9.6 to $170.....  -$18 to $150.
------------------------------------------------------------------------
Non-monetized Benefits..........  26,000 tons of CO.
                                  96 tons of HCl.
                                  5,500 pounds of Hg.
                                  1.6 tons of Cd.
                                  3.0 tons of Pb.
                                  90 grams of CDD/CDF.
                                  Health effects from NOX and SO2
                                   exposure.
                                  Ecosystem effects.
                                  Visibility impairment.
------------------------------------------------------------------------
\1\ All estimates are for the implementation year (2015) and are rounded
  to 2 significant figures. These results include 2 new FB incinerators
  anticipated to come on-line by 2015 and the assumption that small
  entities will landfill.
\2\ The total monetized benefits reflect the human health benefits
  associated with reducing exposure to PM2.5 through reductions of
  directly emitted PM2.5 and PM2.5 precursors such as NOX and SO2. It is
  important to note that the monetized benefits include many but not all
  health effects associated with PM2.5 exposure. Benefits are shown as a
  range from Pope, et al., (2002) to Laden, et al., (2006). These models
  assume that all fine particles, regardless of their chemical
  composition, are equally potent in causing premature mortality because
  there is no clear scientific evidence that would support the
  development of differential effects estimates by particle type. These
  results include 2 new FB incinerators anticipated to come online by
  2015, as well as energy disbenefits of $4.5 to $9.7 million.
\3\ The methodology used to estimate social costs for 1 year in the
  multimarket model using surplus changes results in the same social
  costs for both discount rates.

    For more information on the benefits analysis, please refer to the
RIA for this rulemaking, which is available in the docket.

B. Paperwork Reduction Act

    The information collection requirements in this rule have been
submitted for approval to the OMB under the PRA, 44 U.S.C. 3501 et seq.
The ICR documents prepared by EPA have been assigned EPA ICR number
2369.01 for subpart LLLL, and 2403.01 for subpart MMMM.
    The recordkeeping and reporting requirements in this proposed rule
would be based on the information collection requirements in CAA
section 129 and EPA's NSPS General Provisions (40 CFR part 60, subpart
A). The recordkeeping and reporting requirements in the General
Provisions are mandatory pursuant to CAA section 114 (42 U.S.C. 7414).
All information other than emissions data submitted to EPA pursuant to
the information collection requirements for which a claim of
confidentiality is made is safeguarded according to CAA section 114(c)
and EPA's implementing regulations at 40 CFR part 2, subpart B.
    The requirements in this proposed action result in industry
recordkeeping and reporting burden associated with review of the
amendments for all SSI and initial and annual compliance with the
emission limits using EPA approved emissions test methods. The burden
also includes continuous parameter monitoring and annual inspections of
air pollution control devices that may be used to meet the emission
limits. Operators are required to obtain qualification and complete
annual training. New units are also required to submit a report prior
to construction, including a siting analysis.
    The annual average burden associated with the EG over the first 3
years following promulgation of this proposed action is estimated to be
$14.2 million. This includes 21,900 hours at a total annual labor cost
of $1.2 million and total annualized capital/startup and O&M costs of
$13 million per year, associated with the monitoring requirements,
storage of data and reports and photocopying and postage over the 3-
year period of the ICR. The annual inspection costs are included under
the recordkeeping and reporting labor costs.
    The annual average burden associated with the NSPS over the first 3
years following promulgation of this proposed action is estimated to
involve 518 hours at a total annual labor cost of $29,000. The total
annualized capital/startup costs are estimated at $292,000 per year.
This gives a cumulative annual burden of $321,000 per year for the
NSPS. Burden is defined at 5 CFR 1320.3(b).
    An Agency may not conduct or sponsor, and a person is not required
to respond to a collection of information unless it currently displays
a valid OMB control number. The OMB control numbers for EPA's
regulations are listed in 40 CFR part 9.
    To comment on the Agency's need for this information, the accuracy
of the provided burden estimates, and any suggested methods for
minimizing respondent burden, EPA has established a public docket for
this rule, which includes this ICR, under Docket ID number EPA-HQ-OAR-
2009-0559. Submit any comments related to the ICR to EPA and OMB. See
ADDRESSES section at the beginning of this notice for where to submit
comments to EPA. Send comments to OMB at the Office of Information and
Regulatory Affairs, Office of Management and Budget, 725 17th Street,
NW., Washington, DC 20503, Attention: Desk Office for EPA. Since OMB is
required to make a decision concerning the ICR between 30 and 60 days
after October 14, 2010, a comment to OMB is best assured of having its
full effect if OMB receives it by November 15, 2010. The final rule
will respond to any OMB or public comments on the information
collection requirements contained in this proposal.

C. Regulatory Flexibility Act

    The 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 Agency certifies that the proposed 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 proposed action on
small entities, a small entity is defined as follows: (1) A small
business as defined by the 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 proposed rule on
small entities, I certify that this action will not have a significant
economic impact on a substantial number of small entities. None of the
18 small entities has cost-revenue-ratios greater than 1 percent. Thus,
this is not considered to be a significant impact.
    Although the proposed rule will not have a significant economic
impact on a substantial number of small entities, EPA nonetheless has
tried to reduce the impact of this rule on small entities by allowing
optional CEMS instead of requiring them, allowing information from
tests conducted in recent years to show compliance rather than require
all new testing and allowing reduced testing with continued compliance.

D. Unfunded Mandates Reform Act

    Title II of the UMRA of 1995, 2 U.S.C. 1531-1538, requires Federal
agencies, unless otherwise prohibited by law, to assess the effects of
their regulatory actions on State, local, and tribal governments, and
the private sector. This rule contains a Federal mandate that may
result in expenditures of $100 million or more for State, local, and
tribal governments, in the aggregate, or the private sector in any 1
year. Accordingly, EPA has prepared under section 202 of the UMRA a
written statement that is summarized in this section of the preamble. A
copy of the UMRA written statement can be found in the docket. The UMRA
written statement further describes EPA's statutory authority, a
qualitative and quantitative cost-benefits assessment, and a
description of the extent of EPA's prior consultation with elected
representatives (or their designated authorized employees) of the
affected State, local, and tribal governments, and a summary of their
oral or written comments and concerns and EPA's evaluation of them.
    EPA's statutory authority for this action is contained in CAA
section 129, as described in section II.C of this preamble and in the
UMRA written statement in the docket. These emission standards are also
needed as part of EPA's fulfillment of its obligations under CAA
section 112(c)(3) and (k)(3)(B)(ii). Regarding the cost-benefits
assessment, the RIA prepared for the proposed rule, including the EPA's
assessment of costs and benefits, is detailed in the ``Regulatory
Impact Analysis: Standards of Performance for New Stationary Sources
and Emission Guidelines for Existing Sources: Sewage Sludge
Incineration Units'' in the docket. Based on estimated compliance costs
associated with the proposed rule and the predicted change in prices
and production in the affected industries, the estimated social costs
of the proposed rule are $92 million (2008$). The estimated costs
account for 18 small

entities choosing alternative disposal methods to SSI.
    Consistent with the intergovernmental consultation provisions of
section 204 of the UMRA, EPA has initiated consultations with
governmental entities affected by this proposed rule. EPA invited 10
organizations of elected State and local officials who have been
identified by EPA as the ``Big 10'' organizations appropriate to
contact for purposes of consultation with elected officials. The
following national organizations representing State and local officials
attended a meeting held on May 27, 2010, in Washington, DC: (1)
National Governors' Association, (2) National Conference of State
Legislatures, (3) National League of Cities, (4) U.S. Conference of
Mayors, (5) National Association of Counties, (6) Association of State
and Territorial Solid Waste Management Officials, (7) Council of State
Governments and (8) Environmental Council of the States, to inform them
and seek their input for this rulemaking. Two of the Big 10
organizations were unable to attend. Additionally, the National
Association of Clean Water Agencies, the National Association of Clean
Air Agencies and the Association of State and Interstate Water
Pollution Control Administrators participated, to serve as technical
advisors to the national organizations during this consultation.
    The purpose of the consultation was to provide general background
on the proposal, answer questions, and solicit input from State and
local governments. Prior to the meeting, EPA provided the officials
with a copy of the SSI inventory and presentation. During the meeting,
officials expressed uncertainty with regards to how EPA calculated the
costs to comply with the standard. Officials also expressed uncertainty
with regards to how viable the alternative to the standard is with
respect to small governments and entities located in certain geographic
regions. Technical memoranda, which can be found in the docket,
document EPA's cost analysis, beyond-the-floor options, and the
regulatory impacts analysis. EPA determined that the alternative to the
standard is a viable option for some entities.
    Consistent with section 205 of the UMRA, EPA has identified and
considered a reasonable number of regulatory alternatives. Incineration
continues to be used to dispose of sewage sludge, but is increasingly
becoming less common. Additional pollution controls will increase costs
for facilities that continue to use the incineration disposal method.
If the additional costs are high enough, many POTW may choose to adopt
alternative disposal methods (e.g., surface disposal in landfills or
other beneficial land applications). However, the use of alternative
disposal methods may be limited in some areas because of landfill
capacity constraints, local geography, or other legal or economic
constraints.
    One alternative option is landfilling. Landfilling, in some cases,
provides a simple and low-cost option for sewage sludge disposal.
Sewage sludge may be placed in landfills used for other municipal solid
waste or in landfills constructed specifically for sewage sludge. The
landfill disposal option is attractive for low-volume incinerators;
landfill capacity constraints limit disposal opportunities for large
sludge volumes.
    Land application is a second alternative. Sewage sludge that has
undergone treatment to make it safe for use on other land application
(e.g., fertilizer) is commonly referred to as biosolids. Biosolids can
be sold to agricultural or landscaping entities for land application,
so the organic material in biosolids is reused to contribute to crop
production. Land application has also been used in mine reclamation to
re-establish vegetation.
    Further analysis can be found in the ``Regulatory Impacts
Analysis.'' The regulatory alternative selected is landfilling. EPA
recognizes that the landfilling option may be utilized by some
facilities but not all depending on a number of factors such as cost,
geographic location, and State regulations.
    This proposed rule is not subject to the requirements of section
203 of UMRA because it contains no regulatory requirements that might
significantly or uniquely affect small governments. While some small
governments may have SSI units that would be affected by this rule,
EPA's analysis shows that for the more likely scenario that small
governmental entities switch to landfilling, none of the ratios was
greater than 1 percent. Because the proposed rule's requirements apply
equally to SSI units owned and/or operated by governments or SSI units
owned and/or operated by private entities, there would be no
requirements that uniquely apply to such government or impose any
disproportionate impacts on them.

E. Executive Order 13132: Federalism

    Executive Order 13132 (64 FR 43255, August 10, 1999), requires EPA
to develop an accountable process to ensure ``meaningful and timely
input by State and local officials in the development of regulatory
policies that have federalism implications.'' ``Policies that have
federalism implications'' are defined in the Executive Order to include
regulations that 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.''
    This proposed rule will have federalism implications, as defined by
Agency guidance for implementing the Order, due to substantial direct
compliance costs on State or local governments. As specified by the
Order, EPA must consult with elected State and local government
officials, or their representative national organizations, when
developing regulations and policies that impose substantial compliance
costs on State and local governments. Pursuant to Agency policy, EPA
conducted a briefing for the Big 10 intergovernmental organizations
representing elected State and local government officials, to formally
request their comments and input on the action. Please reference the
UMRA discussion above for further details regarding the Big 10
consultation.
    The Big 10 is currently in the process of providing EPA with
feedback on its proposed standards and EG for SSI units. In the spirit
of Executive Order 13132, and consistent with EPA policy to promote
communications between EPA and State and local governments, EPA
specifically solicits comment on this proposed rule from State and
local officials.

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 SSI owned or operated by Indian tribal governments. Thus,
Executive Order 13175 does not apply to this action.
    EPA specifically solicits additional comment on this proposed
action from tribal officials in the proposal period via the National
Tribal Air Association and other mechanisms.

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 proposed action is
not subject to Executive Order

13045 because it is based solely on technology performance. We note
however, that reductions in air emissions by these facilities will
improve air quality, with expected positive impacts for children's
health.

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 proposed action would cause most SSI 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 29,200 megawatt-hours per year of additional electricity
being used.
    Given the negligible change in energy consumption resulting from
this proposed action, EPA does not expect any significant price
increase for any energy type. The cost of energy distribution should
not be affected by this proposed 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 proposed action, they would
be minimal.

I. National Technology Transfer and Advancement Act

    Section 12(d) of the NTTAA of 1995, Public Law 104-113 (15 U.S.C.
272 note) directs EPA to use 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. The
NTTAA directs EPA to provide Congress, through OMB, explanations when
the Agency decides not to use available and applicable VCS.
    EPA conducted searches for the ``Standards of Performance for New
Stationary Sources and Emission Guidelines for Existing Sources: Sewage
Sludge Incineration Units'' through the Enhanced National Standards
Service Network Database managed by the ANSI. We also contacted VCS
organizations and accessed and searched their databases.
    This rulemaking involves technical standards. EPA has decided to
use ANSI/ASME PTC 19.10-1981, ``Flue and Exhaust Gas Analyses,'' for
its manual methods of measuring the oxygen or carbon dioxide content of
the exhaust gas. These parts of ASME PTC 19.10-1981 are acceptable
alternatives to EPA Methods 6, 7. This standard is available from the
ASME, Three Park Avenue, New York, NY 10016-5990.
    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 an acceptable
alternative to Method 29 and 30B. The EPA has also decided to use EPA
Methods 5, 6, 6C, 7, 7E, 9, 10, 10A, 10B, 22, 23, 26A, 29 and 30B. No
VCS were found for EPA Method 9 and 22.
    During the search, if the title or abstract (if provided) of the
VCS described technical sampling and analytical procedures that are
similar to EPA's reference method, the EPA ordered a copy of the
standard and reviewed it as a potential equivalent method. All
potential standards were reviewed to determine the practicality of the
VCS for this rule. This review requires significant method validation
data which meets the requirements of EPA Method 301 for accepting
alternative methods or scientific, engineering and policy equivalence
to procedures in EPA reference methods. The EPA may reconsider
determinations of impracticality when additional information is
available for particular VCS.
    The search identified 23 other VCS that were potentially applicable
for this rule in lieu of EPA reference methods. After reviewing the
available standards, EPA determined that 23 candidate VCS (ASME B133.9-
1994 (2001), ISO 9096:1992 (2003), ANSIIASME PTC PTC[not]38-1980
(1985), ASTM D3685/D3685M-98 (2005), CAN/CSA Z223.1-M1977, ANSIIASME
PTC 19-10-1981, ISO 10396:1993 (2007), ISO 12039:2001, ASTM D5835-95
(2007), ASTM D6522-00 (2005), CAN/CSA Z223.2-M86 (1999), ISO 7934:1998,
ISO 11632:1998, ASTM D1608-98 (2003), ISO I1564:1998, CAN/CSA Z223.24-
MI983, CAN/CSA Z223.21-MI978, ASTM D3162-94 (2005), EN 1948-3 (1996),
EN 1911-1,2,3 (1998), ASTM D6735-01, EN 13211:2001, CAN/CSA Z223.26-
MI987) identified for measuring emissions of pollutants or their
surrogates subject to emission standards in the rule would not be
practical due to lack of equivalency, documentation, validation data,
and other important technical and policy considerations.
    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, PS, or procedures in the final rule and any amendments.
    EPA welcomes comments on this aspect of the proposed rulemaking and
specifically invites the public to identify potentially-applicable VCS
and to explain why such standards should be used in this regulation.

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 EJ. Its main provision directs Federal
agencies, to the greatest extent practicable and permitted by law, to
make EJ 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 proposed 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. Additionally, the Agency has reviewed this proposed
rule to determine if there was existing disproportionately high and
adverse human health or environmental effects on minority or low-income
populations that could be mitigated by this rulemaking. An analysis of
demographic data showed that the average of populations in close
proximity to the sources, and thus most likely to be effected by the
sources, were similar in demographic composition to national averages.
    In determining the aggregate demographic makeup of the communities
near affected sources, EPA used census data at the block group level to
identify demographics of the populations considered to be living near
affected sources, such that they have notable exposures to current
emissions from these sources. In this approach, EPA reviewed the
distributions of

different socio-demographic groups in the locations of the expected
emission reductions from this rule. The review identified those census
block groups within a circular distance of a half, 3, and 5 miles of
affected sources and determined the demographic and socio-economic
composition (e.g., race, income, education, etc.) of these census block
groups. The radius of 3 miles (or approximately 5 kilometers) has been
used in other demographic analyses focused on areas around potential
sources.27-30 EPA's demographic analysis has shown that
these areas in aggregate have similar proportions of American Indians,
African-Americans, Hispanics, Whites, and ``Other and Multi-racial''
populations, and similar proportions of families with incomes below the
poverty level as the national average.\31\
---------------------------------------------------------------------------

    \27\ U.S. GAO (Government Accountability Office). Demographics
of People Living Near Waste Facilities. Washington, DC: Government
Printing Office; 1995.
    \28\ Mohai P, Saha R. ``Reassessing Racial and Socio-economic
Disparities in Environmental Justice Research.'' Demography.
2006;43(2): 383-399.
    \29\ Mennis J. ``Using Geographic Information Systems to Create
and Analyze Statistical Surfaces of Populations and Risk for
Environmental Justice Analysis.'' Social Science Quarterly,
2002;83(1):281-297.
    \30\ Bullard RD, Mohai P, Wright B, Saha R, et al. Toxic Waste
and Race at Twenty 1987-2007. United Church of Christ. March 2007.
    \31\ The results of the demographic analysis are presented in
``Review of Environmental Justice Impacts,'' June 2010, a copy of
which is available in the docket.
---------------------------------------------------------------------------

    This proposed action establishes national emission standards for