that could be broadly applied to the industry and that was not
identified or considered during development of the original MACT
standards.
     Any significant changes in the cost (including cost
effectiveness) of applying controls (including controls the EPA
considered during the development of the original MACT standards).

    We reviewed a variety of data sources in our investigation of
potential practices, processes or controls to consider. Among the
sources we reviewed were the NESHAP for various industries that were
promulgated since the MACT standards reviewed in this action. We
reviewed the regulatory requirements and/or technical analyses
associated with these regulatory actions to identify any practices,
processes and control technologies considered in these efforts that
could be applied to emission sources in the OSWRO source category, as
well as the costs, non-air impacts and energy implications associated
with the use of these technologies. Additionally, we requested
information from facilities regarding developments in practices,
processes or control technology. Finally, we reviewed information from
other sources, such as state and/or local permitting agency databases
and industry-supported databases.

IV. Analytical Results and Proposed Decisions

    This section of the preamble provides the results of our RTR for
the OSWRO source category and our proposed decisions concerning changes
to the OSWRO NESHAP.

A. What are the results of the risk assessment and analyses?

1. Inhalation Risk Assessment Results
    Table 2 of this preamble provides a summary of the results of the
inhalation risk assessment for the source category.

                                   Table 2--Off-Site Waste and Recovery Operations Inhalation Risk Assessment Results
--------------------------------------------------------------------------------------------------------------------------------------------------------
  Maximum individual cancer risk (in 1 million) \a\                                                Maximum chronic non-cancer
------------------------------------------------------                              Estimated               TOSHI \b\
                                                        Estimated population at   annual cancer --------------------------------
                                            MACT-      increased risk levels of     incidence                         MACT-      Maximum screening acute
        Actual emissions level            allowable             cancer             (cases per        Actual         allowable       non-cancer HQ \d\
                                          emissions                                   year)         emissions       emissions
                                          level \c\                                                   level           level
--------------------------------------------------------------------------------------------------------------------------------------------------------
9....................................              20  >= 1-in-1 million:                  0.02             0.6               1  HQREL = 1 (glycol
                                                        210,000.                                                                  ethers)
                                                       >= 10-in-1 million: 0...
--------------------------------------------------------------------------------------------------------------------------------------------------------
\a\ Estimated maximum individual excess lifetime cancer risk due to HAP emissions from the source category.
\b\ Maximum TOSHI. The target organ with the highest TOSHI for the OSWRO source category for both actual and MACT-allowable emissions is the respiratory
  system.
\c\ The development of allowable emission estimates can be found in the memo entitled MACT-Allowable Emissions for the Off-Site Waste and Recovery
  Operations Source Category, which is available in the docket for this action.
\d\ The maximum off-site acute value of 1 for actuals is driven by emissions of glycol ethers. See Section III.A.E for an explanation of acute dose-
  response values. Acute assessments are not performed with MACT-allowable emissions.

    The inhalation risk modeling performed to estimate risks based on
actual and MACT-allowable emissions relied primarily on data from the
CAA section 114 questionnaire responses and the NEI. The results of the
chronic inhalation cancer risk assessment indicate that, based on
estimates of current actual emissions, the maximum lifetime individual
cancer risk posed by the OSWRO source category is 9-in-1 million, with
emissions of benzidine and 2,4-toluene diamine accounting for the
majority of the risk. The total estimated cancer incidence from the
OSWRO source category based on the actual emissions levels is 0.02
excess cancer cases per year, or one case every 50 years, with
emissions of benzidine and 2,4-toluene diamine contributing to the
majority of the incidence. In addition, we note that approximately
210,000 people are estimated to have cancer risks greater than or equal
to 1-in-1 million as a result of actual emissions from this source
category. When considering MACT-allowable emissions, the maximum
individual lifetime cancer risk is estimated to be up to 20-in-1
million, driven by emissions of benzidine and 2,4-toluene diamine. Due
to the way MACT-allowable risks were calculated, estimates of
population exposure and cancer incidence are not available, but would
be greater than those estimates presented based on actual emissions.
However, since the MIR based on MACT-allowable emissions is 20-in-1
million, there are no people exposed to cancer risks greater than 100-
in-1 million.
    The maximum modeled chronic non-cancer TOSHI value for the OSWRO
source category based on actual emissions was estimated to be 0.6, with
emissions of chlorine contributing to the majority of the TOSHI. There
are no people estimated to have exposure to TOSHI levels greater than 1
as a result of actual emissions from this source category. When
considering MACT-allowable emissions, the maximum chronic non-cancer
TOSHI value was estimated to be up to 1, driven by emissions of
chlorine. There are no people estimated to have exposure to TOSHI
levels greater than 1 as a result of emissions at the MACT-allowable
levels from this source category.
    Our screening analysis for worst-case acute impacts based on actual
emissions indicates that an HQ value of 1 is not exceeded for any
pollutants at any facility, indicating that the HAP emissions are
believed to be without appreciable risk of acute health effects. In
characterizing the potential for acute non-cancer risks of concern, it
is important to remember the upward bias of these exposure estimates
(e.g., worst-case meteorology coinciding with a person located at the
point of maximum concentration during the hour) and to consider the
results along with the conservative estimates used to develop peak
hourly emissions as described earlier. Refer to Appendix 6 of the Draft
Residual Risk Assessment for the Off-Site Waste and Recovery Operations
Source Category in the docket for this action for the detailed acute
risk results.
2. Multipathway Risk Screening Results
    Multiple facilities reported emissions of PB-HAP, including 2-
acetylaminofluorene (a POM compound), heptachlor, and trifluralin. Only
one facility reported emissions of a PB-HAP that has an available RTR
multipathway screening value: 2-acetylaminofluorene, a polycylic
organic matter (POM) compound that was analyzed as benzo(a)pyrene TEQ.
Reported emissions of the POM 2-acetylaminofluorene are below the
multipathway screening level for this compound, indicating low
potential for multipathway risks as a result of emissions of this PB-
HAP. The remaining PB-HAP do not currently have RTR multipathway
screening values, and they were not evaluated for potential non-
inhalation risks. These HAP, however, are not emitted in appreciable
quantities from OSWRO facilities. (For more information on PB-HAP
emitted from this source category, please see the Draft Residual Risk
Assessment for the Off-Site Waste and Recovery Operations Source
Category document available in the docket for this action.)
3. Environmental Risk Screening Results
    As described in section III.A.5, we conducted an environmental risk
screening assessment for the OSWRO source category. Emissions of three
environmental HAP were reported by OSWRO facilities: POM, hydrogen
chloride and hydrogen fluoride. For POM, none of the individual modeled
concentrations for any facility in the source category exceeded any of
the ecological benchmarks (either the LOAEL or NOAEL). For the acid
gases HCl and HF, the average modeled concentration of these chemicals
around each facility (i.e., the average concentration of all off-
facility-site data points in the modeling domain) did not exceed any
ecological benchmarks. In addition, each individual modeled
concentration of hydrogen chloride and hydrogen fluoride (i.e., each
off-facility-site data point in the modeling domain) was below the
ecological benchmarks for all facilities.
4. Facility-wide Inhalation Risk Assessment Results
    Table 3 displays the results of the facility-wide risk assessment.
This assessment is based on actual emission levels. For detailed
facility-specific results, see Appendix 5 of the Draft Residual Risk
Assessment for the Off-Site Waste and Recovery Operations Source
Category in the docket for this proposed rule.

   Table 3--Off-Site Waste and Recovery Operations Facility-Wide Risk
                           Assessment Results
------------------------------------------------------------------------

------------------------------------------------------------------------
Number of facilities analyzed........................                 38
Cancer Risk:
    Estimated maximum facility-wide individual cancer                200
     risk (in 1 million).............................
    Number of facilities with estimated facility-wide                  1
     individual cancer risk of 100-in-1 million or
     more............................................
    Number of facilities at which the OSWRO source                     0
     category contributes 50 percent or more to the
     facility-wide individual cancer risks of 100-in-
     1 million or more...............................
    Number of facilities with estimated facility-wide                 17
     individual cancer risk of 1-in-1 million or more
    Number of facilities at which the OSWRO source                     7
     category contributes 50 percent or more to the
     facility-wide individual cancer risk of 1-in-1
     million or more.................................
Chronic Non-cancer Risk:
    Maximum facility-wide chronic non-cancer TOSHI...                  4
    Number of facilities with facility-wide maximum                    2
     non-cancer TOSHI greater than 1.................
    Number of facilities at which the OSWRO source                     0
     category contributes 50 percent or more to the
     facility-wide maximum non-cancer TOSHI of 1 or
     more............................................
------------------------------------------------------------------------

    The facility-wide MIR and TOSHI are based on actual emissions from
all emissions sources at the identified OSWRO facilities. The results
indicate that 17 facilities have a facility-wide cancer MIR greater
than or equal to 1-in-1 million and one facility has a facility-wide
cancer MIR greater than or equal to 100-in-1 million. The maximum
facility-wide MIR is 200-in-1 million due to emissions of beryllium
compounds from the cement manufacturing processes at the facility site,
with emission points from the OSWRO production source category
contributing less than 1 percent of the maximum facility-wide risk. The
results indicate that two facilities have a facility-wide non-cancer
TOSHI greater than or equal to 1. The maximum facility-wide TOSHI is 4,
and this TOSHI occurs at two facilities. At one of these facilities,
the TOSHI is driven mainly by emissions of beryllium compounds from the
same cement manufacturing processes mentioned above. The TOSHI at the
other facility is driven mainly by emissions of chlorine from
industrial inorganic chemical manufacturing processes and synthetic
organic chemical manufacturing processes at the facility site. In each
instance, the OSWRO production source category contributes less than 1
percent to the facility-wide TOSHI. The focus of this analysis is the
OSWRO source category and its low relative contribution to facility-
wide risk. The maximum facility-wide MIR and TOSHI values presented
here are the result of a screening analysis for the other source
categories located at common facility sites. The screening analysis
requires further refinement and takes place during the RTR review for
those source categories. We anticipate reductions of HAP from the
cement manufacturing processes due to the implementation of the
recently promulgated MACT standard, with a compliance date of September
9, 2015, and the upcoming RTR review, with a consent decree deadline of
June 15, 2017 for proposal and June 15, 2018 for promulgation. We may
consider options for achieving further reduction of HAP from the
inorganic chemical and synthetic organic chemical manufacturing
processes in future reviews for those source categories.
5. What demographic groups might benefit from this regulation?
    To determine whether or not to conduct a demographics analysis,
which is an assessment of risks to individual demographic groups, we
look at a combination of factors including the MIR, non-cancer TOSHI,
population around the facilities in the source category, and other
relevant factors. Actual emissions from the OSWRO source category
result in no individuals being exposed to cancer risk greater than 9-
in-1 million or a non-cancer TOSHI greater than 1. In addition, we
estimate the cancer incidence for the source category to be 0.02 cases
per year. Therefore, we did not conduct an assessment of risks to
individual demographic groups for this proposed rule. However, we did
conduct a proximity analysis, which identifies any overrepresentation
of minority, low income or indigenous populations near facilities in
the source category. The results of this analysis are presented in the
section of this preamble entitled ``Executive Order 12898: Federal
Actions to Address Environmental Justice in Minority Populations and
Low-Income Populations.''

B. What are our proposed decisions regarding risk acceptability, ample
margin of safety and adverse environmental effects?

1. Risk Acceptability
    As discussed in sections II.A and III.B of this preamble, we weigh
all health risk factors in our risk acceptability determination,
including the cancer MIR; the number of persons in various cancer and
non-cancer risk ranges; cancer incidence; the maximum non-cancer TOSHI;
the maximum acute non-cancer HQ; the extent of non-cancer risks; the
potential for adverse environmental effects; the distribution of cancer
and non-cancer risks in the exposed population; and risk estimation
uncertainties (54 FR 38044, September 14, 1989).
    For the OSWRO source category, the risk analysis we performed
indicates that the cancer risks to the individual most exposed could be
up to 9-in-1 million due to actual emissions and up to 20-in-1 million
due to MACT-allowable emissions. These risks are considerably less than
100-in-1 million, which is the presumptive upper limit of acceptable
risk. The risk analysis also shows relatively low cancer incidence
(0.02 cases per year), as well as no appreciable risk of deleterious
chronic or acute non-cancer health effects. In addition, the risk
assessment indicates no significant potential multipathway health
effects.
    While our analysis of facility-wide risks shows one facility with a
maximum facility-wide cancer risk of 100-in-1 million or greater and
two facilities with a maximum chronic non-cancer TOSHI greater than 1,
it also shows that OSWRO operations did not drive these risks. In fact,
OSWRO operations contribute less than 1 percent to the cancer MIR and
less than 1 percent to the non-cancer TOSHI).
    Considering all of the health risk information and factors
discussed above, including the uncertainties discussed in section
III.A.8 of this preamble, we propose that the risks from the OSWRO
source category are acceptable.
2. Ample Margin of Safety Analyses and Proposed Controls
    Although we are proposing that the risks from the OSWRO source
category are acceptable, risk estimates for 210,000 individuals in the
exposed population are above 1-in-1 million based on actual emissions.
We recognize that our risk analysis indicates that the cancer risks to
the individual most exposed are well within EPA's acceptable range
(i.e., up to 9-in-1 million due to actual emissions and up to 20-in-1
million due to MACT-allowable emissions). However, as stated in the
Benzene NESHAP, in protecting public health with an ample margin of
safety, ``EPA strives to provide maximum feasible protection against
risks to health from HAP,'' considering available health information,
the incremental risk reduction associated with more stringent
standards, technological feasibility, and other factors, such as costs
and economic impacts of controls. 54 FR at 38044-38045. Consequently,
in this analysis, we investigated available emissions control options
that might reduce the risk associated with emissions from the source
category. We considered this information along with all of the health
risks and other health information considered in determining risk
acceptability. As explained below, we are proposing additional control
requirements for equipment leaks and certain tanks because considering
costs and other factors, we have determined that these additional
controls are capable of further reducing risks to the individual most
exposed, and thus, they provide an ample margin of safety.
    For the OSWRO source category, we did not identify any options that
would reduce HAP emissions from containers, surface impoundments, oil-
water separators, organic-water separators or transfer systems beyond
what is currently required in the rule. For process vents, tanks and
equipment leaks, we identified additional control options, which are
described below.
    For 19 of the 38 facilities included in the OSWRO risk analysis,
the available data (see discussion of emissions data in section III.A
of this preamble) did not,

in general, attribute OSWRO emissions to specific emission sources. For
example, the NEI data for many of these facilities grouped emissions
under source classification codes (SCC) for non-specific processes,
such as 39999999--Miscellaneous Industrial Processes. For these
facilities, we lack information as to which processes and emission
point types are contributing to the risk estimates developed in the
risk assessment. In contrast, CAA section 114 response data for the
other 19 facilities were available, and the emissions data for these
facilities were attributed to specific emission point types. However,
the maximum cancer MIR and noncancer TOSHI values for the OSWRO source
category are attributed to a facility for which only NEI data are
available and for which we lack information regarding the processes and
emission point types that contribute to these maximum risk values.
Because we were unable to precisely determine the magnitude of HAP
emissions from specific process types and how those emissions relate to
the risk estimates, we conservatively assumed that the type of
equipment under investigation was responsible for the maximum risks.
For example, in our assessment of process vents, we assumed the maximum
risks for the OSWRO source category were due to process vents, and then
we evaluated how further controls might reduce this risk. While these
assumptions may introduce some uncertainty regarding the risk
reductions that would be achieved for each equipment type, we are
presenting our analysis using the best information available. As noted
in section VI of this preamble, we are requesting commenters to provide
any site-specific emissions or other data that would enable us to
better characterize the maximum risks and the risk reductions from the
proposed control options for the OSWRO source category.
    In the ample margin of safety analysis, factors related to the
appropriate level of control are considered, including the costs and
economic impacts of the controls. For the OSWRO source category, the
control options identified to reduce risks are the same as those
identified in the technology review. As such, we relied on the control
cost estimates and estimates of control cost effectiveness derived from
the technology review analyses in our ample margin of safety
determination. We believe that our ample margin of safety analysis is
reasonable. However, we note that if we had data to more precisely
assign HAP emissions to particular emission sources in the risk
modeling file and if that data were to lead us to conclude that the
MACT standards reflect an ample margin of safety, we are still
proposing these same control options under the technology review
because they are technologically applicable and cost effective for this
source category based on our experience with similar emission sources
emitting similar HAP at other chemical type facilities. We request
comments on the proposed controls discussed below to provide an ample
margin of safety for this source category.
    For process vents, as discussed in section IV.C of this preamble,
we identified an emissions control option of requiring compliance with
a 98 percent reduction rather than a 95 percent reduction in HAP
emissions. To assess the maximum potential for risk reduction that
could result from this process vent control option, we assumed that the
maximum risks for the OSWRO source category are due to emissions from a
process vent with emissions controlled at 95 percent. In this scenario,
we estimate the HAP reduction resulting from compliance with a 98
percent reduction would be 10 tpy from the current emissions level,
with a cost effectiveness of $350,000/ton HAP reduction. We estimate
this option would reduce the MIR at the MACT-allowable emissions level
for the source category from 20-in-1 million to 8-in-1 million and
reduce the maximum chronic non-cancer TOSHI from 1 to 0.4. Considering
all of the health risks and other health information considered in our
determination of risk acceptability, the potential for reductions in
HAP emissions and risk, the uncertainty associated with the estimated
potential risk reductions and the costs associated with this option, we
are proposing that no additional HAP emissions controls for OSWRO
process vents are necessary to provide an ample margin of safety to
protect public health.
    For tanks, as discussed in section IV.C of this preamble, we
identified two emissions control options. Option 1 requires Level 2
control of emissions for additional tanks containing liquids with lower
vapor pressures. Option 2 requires compliance with a 98 percent
reduction rather than a 95 percent reduction in HAP emissions from
tanks. As discussed above for process vents, to assess the maximum
potential for risk reduction that could result from these two tank
control options, we have assumed that the maximum risks for the OSWRO
source category are due to emissions from tanks. For Option 1, we have
assumed that the maximum risks are due to tanks that are not currently
subject to Level 2 controls, which require a 95 percent reduction in
emissions. In this scenario, we estimate the HAP reduction resulting
from compliance with the control of additional tanks would be 73 tpy
from the current emissions level, with a cost effectiveness of $300/ton
HAP reduction. We estimate this option would reduce the MIR at the
MACT-allowable emissions level for the source category from 20-in-1
million to 1-in-1 million and reduce the maximum chronic non-cancer
TOSHI from 1 to 0.05. Under Option 2, we estimate the HAP reduction
incremental to Option 1 would be approximately 22 tpy, with a cost
effectiveness of $13,000/ton HAP reduction and a cost effectiveness
incremental to Option 1 of $56,000/ton HAP reduction. We estimate this
option would reduce the MIR at the MACT-allowable emissions level
incremental to Option 1 for the source category from 1-in-1 million to
0.4-in-1 million and reduce the maximum chronic non-cancer TOSHI from
0.05 to 0.02. Considering all of the health risks and other health
information considered in our determination of risk acceptability, the
potential risk reductions and the costs associated with Option 1, we
are proposing to require this additional level of control to provide an
ample margin of safety. Considering all of the health risks and other
health information considered in our determination of risk
acceptability, the potential for reductions in risk, the uncertainty
associated with the estimated potential risk reductions and the costs
associated with Option 2, we are proposing that the additional HAP
emissions controls for OSWRO tanks under Option 2 are not necessary to
provide an ample margin of safety to protect public health. In
addition, as discussed further in preamble section IV.C, we are also
proposing the Option 1 additional control level as a result of the
technology review.
    For equipment leaks, as discussed in section IV.C of this preamble,
we identified two emission control options: Option 1 requires
compliance with 40 CFR part 63, subpart H, rather than 40 CFR part 61,
subpart V, without the connector leak detection and repair (LDAR)
requirements of subpart H; Option 2 requires the same as Option 1 but
includes the connector LDAR requirement of subpart H. As discussed
above for tanks, to assess the maximum potential for risk reduction
that could result from these equipment leaks control options, we
assumed that the maximum risks for the OSWRO source category are due to
emissions from equipment leaks. We also assumed that

since emissions from equipment leaks are estimated to be the same at
actual and MACT-allowable emission levels, the risks due to equipment
leaks at the MACT-allowable level are the same as risks due to
equipment leaks at actual emissions levels. We additionally assumed,
based on our analysis of estimated baseline equipment leak
emissions,\24\ that half of the equipment leak emissions causing the
maximum risks are from non-connector components (i.e. pumps and
valves), and the other half are from connectors. Given these
assumptions, under Option 1, we estimate the HAP reduction resulting
from compliance with subpart H without the subpart H connector
monitoring requirements would be 69 tpy from the baseline actual
emissions level, with a cost effectiveness of $1,000/ton HAP reduction.
We estimate this option would reduce the MIR at the MACT-allowable
emissions level for the equipment leaks at the source category from 9-
in-1 million to 7-in-1 million and reduce the maximum chronic non-
cancer TOSHI from 0.6 to 0.5. Under Option 2, we estimate the
incremental HAP reduction resulting from compliance with subpart H
including the subpart H connector monitoring requirements would be 70
tpy more than Option 1, with an overall cost effectiveness of $4,000/
ton HAP reduction and a cost effectiveness incremental to Option 1 of
$7,000/ton HAP reduction. We estimate this option would reduce the MIR
at the MACT-allowable emissions level incremental to Option 1 for the
equipment leaks at the source category from 7-in-1 million to 5-in-1
million and reduce the maximum chronic non-cancer TOSHI from 0.5 to
0.3. We note, as discussed in preamble section IV.C, we are proposing
the additional control level of Option 2 as a result of the technology
review. Considering the health risks and other health information
evaluated in our determination of risk acceptability, that some risk
reduction occurs with Option 2, and the costs associated with Option 2
are reasonable, we are proposing to require this additional level of
control to provide an ample margin of safety.
---------------------------------------------------------------------------

    \24\ See Technology Review and Cost Impacts for the Proposed
Amendments to the Off-Site Waste and Recovery Operations Source
Category, which is available in the docket for this action.
---------------------------------------------------------------------------

    In accordance with the approach established in the Benzene NESHAP,
the EPA weighed all health risk measures and information considered in
the risk acceptability determination, along with the costs of emissions
controls, technological feasibility, uncertainties and other relevant
factors in making our ample margin of safety determination. Considering
the health risk information, the potential risk reductions and the
reasonable cost effectiveness of certain control options identified for
tanks and equipment leaks, we propose that the standards for the OSWRO
source category be revised to include the proposed control Option 1 for
tanks and the proposed control Option 2 for equipment leaks to provide
an ample margin of safety to protect public health.
3. Adverse Environmental Effects
    We conducted an environmental risk screening assessment for the
OSWRO source category for POM, HCl and HF. For POM, none of the
individual modeled Tier I concentrations for any facility in the source
category exceeded any of the ecological benchmarks (either the LOAEL or
NOAEL). For HF and HCl, the average modeled concentration around each
facility (i.e., the average concentration of all off-site data points
in the modeling domain) did not exceed any ecological benchmark. Based
on these results, we are proposing that it is not necessary to set a
more stringent standard to prevent such an adverse environmental
effect, taking into consideration costs, energy, safety, and other
relevant factors.

C. What are the results of the technology review and our proposed
decisions?

    As described in section III.C of this preamble, our technology
review focused on identifying developments in practices, processes and
control technologies for the emission sources in the OSWRO production
source category. To identify such developments since the MACT standards
were developed, we consulted the EPA's RACT/BACT/LAER Clearinghouse,
reviewed subsequent regulatory development efforts and reviewed data
from the 2013 CAA Section 114 survey of OSWRO facilities. For the OSWRO
source category, we did not identify any developments in practices,
processes or control technologies for containers, surface impoundments,
oil-water separators, organic-water separators or transfer systems
beyond what is currently required in the rule. For process vents, tanks
and equipment leaks, we identified additional control options, and the
following sections summarize the results of our technology review for
these emissions sources.
    To perform the technology review, we needed information that was
not included in the RTR emissions dataset used for modeling OSWRO
risks. Therefore, to evaluate the costs and cost-effectiveness of
various control options, we used a model plant approach. The model
plant approach we used resulted in different baseline emission
estimates than those included in the risk modeling dataset. More
information concerning our technology review and model plant approach
can be found in the memorandum titled, Technology Review and Cost
Impacts for the Proposed Amendments to the Off-Site Waste and Recovery
Operations Source Category, which is available in the docket for this
action.
1. Tanks
    For tanks at existing affected sources, we identified two potential
developments in practices and control techniques. The current OSWRO
MACT requirements at 40 CFR 63.685(b)(1) for tanks at an existing
affected source depend on the capacity of the tank and the vapor
pressure of the material being stored. ``Level 2'' control is required
for: (1) Tanks with capacities greater than or equal to 75 cubic meters
(m\3\), but less than 151 m\3\ and a vapor pressure of 27.6 kilopascals
(kPa) or greater and (2) tanks with capacities greater than or equal to
151 m\3\ and a vapor pressure of 5.2 kPa or greater. ``Level 2''
control essentially requires one of five options: (1) A fixed roof tank
equipped with an internal floating roof; (2) a fixed roof tank equipped
with an external floating roof; (3) a tank with a vapor-tight cover and
vented through a closed-vent system to a control device that has an
efficiency of 95 percent or more; (4) a pressure tank; or (5) a tank
inside a permanent total enclosure (PTE) that is vented through a
closed-vent system to an enclosed combustion control device. Tanks of
any capacity (effectively those less than 75 m\3\) with a vapor
pressure of 76.6 kPa or greater are required to use one of the options
listed above for Level 2 control, except that fixed roof tanks with
either an internal or an external floating roof cannot be used. For
tanks with capacities and vapor pressures less than those stated above,
``Level 1'' control is required. ``Level 1'' control generally requires
a fixed roof with closure devices.
    We evaluated two control options that would change the tank
requirements if adopted. Option 1 would lower the vapor pressure
threshold above which Level 2 controls would be required for some
tanks. Option 2 would revise the vapor pressure threshold as in Option
1 and increase the required control efficiency from the current 95
percent to a 98 percent emissions reduction for all tanks required to
use Level 2 controls. Through the review of air toxics MACT standards
developed subsequent to the

OSWRO MACT standards, we noted that several other MACT standards refer
to the Hazardous Organic NESHAP (HON) for their storage tank
requirements. We evaluated revising the applicability of the OSWRO
existing source requirements to use the same thresholds for Level 2
control as the thresholds for control required by the HON. As shown in
Table 4, Option 1 would require Level 2 emissions control for tanks
with capacities greater than or equal to 75 m\3\, but less than 151
m\3\, if the vapor pressure of the stored material is 13 kPa or
greater, instead of 27.6 kPa or greater as required by the current MACT
standard. No other tank size or vapor thresholds would be changed with
Option 1. For tanks at new affected sources, the current OSWRO
applicability thresholds are consistent with those required for the
chemical industry under other NESHAP, including the HON, so no revised
applicability requirements were evaluated for tanks located at new
sources.
    Because available data for the source category indicate most OSWRO
tanks currently have fixed-roofs with emissions routed through a closed
vent system to a control device, under Option 2 we considered the
impacts of requiring a higher control efficiency than currently
required by the OSWRO MACT standard. While carbon adsorption and other
control devices are assumed to have a control efficiency of 95 percent,
other technologies are capable of achieving greater emissions control,
such as thermal incinerators. Several of these devices have been
demonstrated to achieve a control efficiency of 98 percent or greater.
Under Option 2, we considered the impacts of requiring a 98 percent
emissions reduction for tanks meeting the lowered vapor pressure
threshold under Option 1, and all other tanks required to use Level 2
emission controls, assuming a recuperative thermal oxidizer (RCO) would
be used to attain this increased level of control.
    Table 5 presents the emission reductions and costs of the two
options considered for tanks at existing affected sources in the OSWRO
source category under the technology review. For Option 1, data
collected through our CAA section 114 questionnaire indicate that only
some facilities have tanks in the size and vapor pressure range
considered for this option, and based on these data we estimate that
approximately three OSWRO facilities have tanks that would require
additional control under Option 1. As seen in Table 5, for Option 1, we
estimate the capital costs to be approximately $76,000, and the total
annualized costs are estimated to be approximately $21,000. The
estimated HAP emissions reduction is approximately 73 tpy, and the cost
effectiveness is approximately $300/ton. For Option 2, data collected
through our CAA section 114 questionnaire indicate that only some
facilities have tanks that currently require Level 2 emissions controls
or that would require Level 2 control with the revised vapor pressure
threshold of Option 1, and based on this data we estimate that
approximately 10 OSWRO facilities have tanks that would require
additional control under Option 2. We estimate the capital costs to be
approximately $2.8 million, and the total annualized costs are
estimated to be approximately $1.3 million. The estimated HAP emissions
reduction incremental to Option 1 is approximately 22 tpy, and the
incremental cost effectiveness between Option 1 and Option 2 is
approximately $56,000/ton.

                Table 4--Requirements of Tank Options 1 and 2 for Existing OSWRO Affected Sources
----------------------------------------------------------------------------------------------------------------
     Options 1 and 2 applicability thresholds
---------------------------------------------------  Then control
                                       And vapor       level for    Option 1 Requirements  Option 2 Requirements
         If size (m\3\) is          pressure (kPa)   options 1 and
                                          is               2
----------------------------------------------------------------------------------------------------------------
<75...............................           <76.6               1                   Fixed roof.
                                   -----------------------------------------------------------------------------
                                            >=76.6           \a\ 2  95% control \b\......  98% control.\b\
----------------------------------------------------------------------------------------------------------------
75 <= capacity < 151..............           <13.1               1                   Fixed roof.
                                   -----------------------------------------------------------------------------
                                            >=13.1               2  95% control \c\......  98% control.\c\
----------------------------------------------------------------------------------------------------------------
151 <= capacity...................            <5.2               1                   Fixed roof.
                                   -----------------------------------------------------------------------------
                                             >=5.2               2  95% control \c\......  98% control.\c\
----------------------------------------------------------------------------------------------------------------
\a\ Except that fixed roof tanks equipped with an internal floating roof and tanks equipped with an external
  floating roof shall not be used.
\b\ Control efficiency would apply to tanks vented through a closed vent system to a control device and tanks
  inside a PTE that are vented to a combustion control device; use of a pressure tank would still be an
  available control option.
\c\ Control efficiency would apply to tanks vented through a closed vent system to a control device and tanks
  inside a PTE that are vented to a combustion control device; use of an internal or external floating roof or a
  pressure tank would still be available control options.

                           Table 5--Nationwide Emissions Reductions and Costs of Control Options for Tanks at OSWRO Facilities
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                Cost
                                                                  HAP emissions                      Annual cost ($/    effectiveness   Incremental cost
                      Regulatory options                         reduction (tpy)  Capital cost ($)         yr)           ($/ton HAP     effectiveness ($/
                                                                                removed)      ton HAP removed)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Option 1......................................................              72.8            76,000            21,000               300  ................
Option 2......................................................              95.0         2,800,000         1,300,000            13,000            56,000
--------------------------------------------------------------------------------------------------------------------------------------------------------

    Based on our analysis, the costs of Option 1 are reasonable, given
the level of HAP emissions reduction that would be achieved with this
control option. The costs of Option 2 do not appear reasonable, given
the level of HAP emissions reduction it would achieve. Therefore, as a
result of the technology review, we are proposing to revise the

OSWRO MACT standards in accordance with Option 1, i.e., to require
Level 2 controls for tanks at existing affected sources with capacities
greater than or equal to 75 m\3\, but less than 151 m\3\, and a vapor
pressure of 13.1 kPa or greater. We solicit comment on our assessment
and conclusions regarding all aspects of both options. As noted in
section IV.B.2, we are concurrently proposing to revise the OSWRO MACT
standards for existing affected sources to require Level 2 controls for
these tanks under section 112(f)(2) of the CAA to provide an ample
margin of safety to protect public health.
2. Equipment Leaks
    The OSWRO MACT standards at 40 CFR 63.691 currently require
compliance with either 40 CFR part 61, subpart V, or 40 CFR part 63,
subpart H, to control emissions from equipment leaks at existing and
new affected sources. While many provisions of these two rules are the
same or similar, subpart H requires the use of a more stringent leak
definition for valves in gas and vapor service and in light liquid
service, pumps in light liquid service, and connectors. Specifically,
subpart H lowers the leak definition for valves from 10,000 ppm (in
subpart V) to 500 ppm, lowers the leak definition for pump seals from
10,000 ppm (in subpart V) to 1,000 ppm, and requires periodic
instrument monitoring of connectors with a leak definition of 500 ppm,
as opposed to instrument monitoring only being required if a potential
leak is detected by visual, audible, olfactory, or other detection
method (in subpart V). We identified the more stringent leak
definitions of subpart H as a development in practices, processes or
control technologies.
    Assuming conservatively that each of the OSWRO facilities currently
comply with subpart V and do not already comply with subpart H, we
analyzed the costs and emission reductions of two options: Option 1--
switching from a subpart V LDAR program to a subpart H LDAR program,
without the subpart H connector monitoring requirements; Option 2--
switching from a subpart V LDAR program to a subpart H LDAR program,
with the subpart H connector monitoring requirements. The estimated
costs and emissions reductions associated with these two options for
the OSWRO source category are shown in Table 6. For Option 1 (subpart H
without connector monitoring), we estimated the capital costs to be
approximately $320,000, and the total annualized costs are estimated to
be approximately $67,000. The estimated HAP emissions reduction is
approximately 69 tpy, and the cost effectiveness is approximately
$1,000/ton. For Option 2 (subpart H with connector monitoring), we
estimated the capital costs to be approximately $1,900,000, and the
total annualized costs are estimated to be approximately $530,000. The
estimated HAP emissions reduction is approximately 138 tpy, and the
cost effectiveness is approximately $4,000/ton. The incremental cost
effectiveness between Option 1 and Option 2 is approximately $7,000.

                                           Table 6--OSWRO Equipment Leak Options Emission Reductions and Costs
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                Cost        Incremental cost
                    Regulatory alternatives                       HAP Emissions   Capital cost ($)   Annual cost ($/  effectiveness ($/ effectiveness ($/
                                                                 reduction (tpy)                           yr)        ton HAP removed)  ton HAP removed)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Option 1: Subpart H, no connector monitoring..................              68.5           320,000            67,000             1,000  ................
Option 2: Subpart H with connector monitoring.................             138.1         1,900,000           530,000             4,000             7,000
--------------------------------------------------------------------------------------------------------------------------------------------------------

    Based on our analysis, the costs of Option 2, which includes all of
the requirements of Option 1, are reasonable, given the level of HAP
emissions reduction that would be achieved with this control option.
Therefore, as a result of the technology review, we are proposing to
revise the OSWRO MACT standards, in accordance with Option 2, to
require existing and new affected sources to comply with subpart H
rather than subpart V, including the subpart H requirements for
connectors in gas and vapor service and in light liquid service. As
noted in section IV.B.2, we are concurrently proposing to revise the
OSWRO MACT standards for existing and new affected sources to require
compliance with subpart H rather than subpart V, including the subpart
H requirements for connectors in gas and vapor service and in light
liquid service under section 112(f)(2) of the CAA to provide an ample
margin of safety to protect public health. We solicit comment on our
assessment and conclusions regarding all aspects of both options.
3. Process Vents
    The current OSWRO MACT standards at 40 CFR 63.690 require emissions
from process vents at existing and new affected sources to be routed
through a closed vent system to a control device achieving at least 95
percent control. As discussed above for tanks, while carbon adsorption
and other control devices are assumed to have a control efficiency of
95 percent, other technologies are capable of achieving greater
emissions control, such as thermal incinerators. Several of these
devices have been demonstrated to achieve a control efficiency of 98
percent or greater. Based on the combination of reported control
efficiencies for these devices and known application to low
concentration organic vapor gas streams, we investigated the use of a
regenerative thermal oxidizer with a control efficiency of 98 percent
as a potential control option.
    Table 7 presents the emission reductions and costs of the 98
percent control options considered for process vents at existing
affected sources in the OSWRO source category under the technology
review. Data collected through our CAA section 114 questionnaire
indicate that only some facilities have process vents, and based on
these data we estimate that approximately eight OSWRO facilities have
process vents that would require additional control to reduce emissions
by 98 percent. We estimated the capital costs of complying with an
increase from 95 to 98 percent HAP control for process vents to be
approximately $9.8 million, and the total annualized costs are
estimated to be approximately $3.3 million. The estimated HAP emissions
reduction is approximately 10 tpy, and the cost effectiveness is
approximately $350,000/ton of HAP emission reduction.

                                   Table 7--OSWRO Process Vent Option Impacts
----------------------------------------------------------------------------------------------------------------
                                                                                Cost
          Regulatory option             HAP emissions     Capital cost ($)   Annual cost ($/   effectiveness ($/
                                       reduction (tpy)                             yr)          ton HAP removed)
----------------------------------------------------------------------------------------------------------------
98 percent control..................               9.6          9,800,000          3,300,000            350,000
----------------------------------------------------------------------------------------------------------------

    Based on our estimate of costs and HAP reduction, we do not
consider increasing the emission reduction to 98 percent to be
reasonable, and we are not proposing to revise the OSWRO MACT standards
for process vents pursuant to CAA section 112(d)(6) to require this
level of emissions control. We solicit comment on our analysis, and as
noted in section IV.B.2, we also solicit comments regarding the
emissions controls proposed as a result of this technology review,
given the uncertainty in the emissions estimates and the potential
impact on the estimates of cost effectiveness.

D. What other actions are we proposing?

    We are also proposing revisions to the startup, shutdown and
malfunction (SSM) provisions of the MACT rule to ensure that they are
consistent with the court decision in Sierra Club v. EPA, 551 F. 3d
1019 (D.C. Cir. 2008), which vacated two provisions that exempted
sources from the requirement to comply with otherwise applicable
section 112(d) emission standards during periods of SSM. Second, we are
proposing to require electronic reporting of emissions test results.
Third, we are proposing to revise the routine maintenance provisions
and limit those provisions only to tanks routing emissions to a control
device. Fourth, we are proposing to clarify what ``seal the open end at
all times'' means for open-ended lines and valves in the equipment leak
provisions of the rule. Fifth, we are proposing that emissions of HAP
from safety devices and closure devices directly to the atmosphere are
prohibited, and we are proposing to require monitoring of pressure
releases from pressure relief devices (PRDs) that release directly to
the atmosphere. Sixth, we are proposing minor clarifications to the
sample run times and sample site location required for some performance
test methods, and we are proposing to allow the use of a different
performance test method in two cases. Seventh, we are proposing various
minor clarifications and corrections to the rule. In addition to these
proposed revisions, we are seeking comments containing information
regarding flares used by facilities in this source category. We present
details and the rationales for the proposed changes in the following
sections.
1. Startup, Shutdown and Malfunctions
a. Background
    In its 2008 decision in Sierra Club v. EPA, 551 F.3d 1019 (D.C.
Cir. 2008), the United States Court of Appeals for the District of
Columbia Circuit vacated portions of two provisions in the EPA's CAA
section 112 regulations governing the emissions of HAP during periods
of SSM. Specifically, the Court vacated the SSM exemption contained in
40 CFR 63.6(f)(1) and 40 CFR 63.6(h)(1) holding that under section
302(k) of the CAA, emissions standards or limitations must be
continuous in nature and that the SSM exemption violates the CAA's
requirement that some section 112 standards apply continuously.
    We are proposing to eliminate the SSM exemption in the OSWRO
NESHAP. Consistent with Sierra Club v. EPA, we are proposing standards
in this rule that apply at all times. We are also proposing several
revisions to Table 2 (the General Provisions Applicability Table) as is
explained in more detail below. For example, we are proposing to
eliminate the incorporation of the General Provisions' requirement that
the source develop an SSM plan. We also are proposing to eliminate and
revise certain recordkeeping and reporting requirements related to the
SSM exemption as further described below.
    The EPA has attempted to eliminate provisions that are
inappropriate, unnecessary, or redundant in the absence of the SSM
exemption in this proposal. We are specifically seeking comment on
whether we have successfully done so.
    In proposing the standards in this rule, the EPA has taken into
account startup and shutdown periods and, for the reasons explained
below, has not proposed alternate standards for those periods.
    Information on periods of startup and shutdown received from OSWRO
facilities through the CAA section 114 questionnaire responses indicate
that emissions during these periods are the same as during normal
operations. The facilities do not process waste unless and until their
control devices are operating to fully control emissions. Therefore,
separate standards for periods of startup and shutdown are not
necessary and are not being proposed. We solicit comment on our
findings and conclusions regarding periods of startup and shutdown at
OSWRO facilities.
    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). The EPA has determined that CAA
section 112 does not require that emissions that occur during periods
of malfunction be factored into development of CAA section 112
standards. Under section 112, emissions standards for new sources must
be no less stringent than the level ``achieved'' by the best controlled
similar source and for existing sources generally must be no less
stringent than the average emission limitation ``achieved'' by the best
performing 12 percent of sources in the category. There is nothing in
section 112 that directs the EPA to consider malfunctions in
determining the level ``achieved'' by the best performing sources when
setting emission standards. As the DC Circuit has recognized, the
phrase ``average emissions limitation achieved by the best performing
12 percent of sources ``says nothing about how the performance of the
best units is to be calculated.'' Nat'l Ass'n of Clean Water Agencies
v. EPA, 734 F.3d 1115, 1141 (D.C. Cir. 2013). While the EPA accounts
for variability in setting emissions standards, nothing in section 112
requires the EPA to consider malfunctions as part of that analysis. A
malfunction should not be treated in the same manner as the type of
variation in performance that occurs during routine operations of a
source. A malfunction is a failure of the source to perform in a
``normal or usual manner'' and no statutory language compels the EPA to
consider such events in setting standards based on ``best performers.''
    Further, accounting for malfunctions in setting emissions standards
would be difficult, if not impossible, given the

myriad different types of malfunctions that can occur across all
sources in the category and given the difficulties associated with
predicting or accounting for the frequency, degree, and duration of
various malfunctions that might occur. As such, the performance of
units that are malfunctioning is not ``reasonably'' foreseeable. See,
e.g., Sierra Club v. EPA, 167 F. 3d 658, 662 (D.C. Cir. 1999) (the EPA
typically has wide latitude in determining the extent of data-gathering
necessary to solve a problem. We generally defer to an agency's
decision to proceed on the basis of imperfect scientific information,
rather than to ``invest the resources to conduct the perfect study.'').
See also Weyerhaeuser v. Costle, 590 F.2d 1011, 1058 (D.C. Cir. 1978)
(``In the nature of things, no general limit, individual permit, or
even any upset provision can anticipate all upset situations. After a
certain point, the transgression of regulatory limits caused by
`uncontrollable acts of third parties,' such as strikes, sabotage,
operator intoxication or insanity, and a variety of other
eventualities, must be a matter for the administrative exercise of
case-by-case enforcement discretion, not for specification in advance
by regulation.''). In addition, the goal of a ``best controlled or best
performing source'' is to operate in such a way as to avoid
malfunctions of the source and accounting for malfunctions could lead
to standards that are significantly less stringent than levels that are
achieved by a well-performing non-malfunctioning source. It is
reasonable to interpret section 112 to avoid such a result. The EPA's
approach to malfunctions is consistent with CAA section 112 and is a
reasonable interpretation of the statute.
    In the event that a source fails to comply with the applicable CAA
section 112(d) standards as a result of a malfunction event, the 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.
The EPA would also consider whether the source's failure to comply with
the CAA section 112(d) standard was, in fact, ``sudden, infrequent, not
reasonably preventable'' and was not instead ``caused in part by poor
maintenance or careless operation.'' 40 CFR 63.2 (definition of
malfunction). Further, to the extent the EPA files an enforcement
action against a source for violation of an emission standard, the
source can raise any and all defenses in that enforcement action, and
the federal district court will determine what, if any, relief is
appropriate. The same is true for citizen enforcement actions.
Similarly, the presiding officer in an administrative proceeding can
consider any defense raised and determine whether administrative
penalties are appropriate.
    In several prior rules, the EPA had included an affirmative defense
to civil penalties for violations caused by malfunctions in an effort
to create a system that incorporates some flexibility, recognizing that
there is a tension, inherent in many types of air regulations, to
ensure adequate compliance, while simultaneously recognizing that
despite the most diligent of efforts, emission standards may be
violated under circumstances entirely beyond the control of the source.
Although the EPA recognized that its case-by-case enforcement
discretion provides sufficient flexibility in these circumstances, it
included the affirmative defense to provide a more formalized approach
and more regulatory clarity. See Weyerhaeuser Co. v. Costle, 590 F.2d
1011, 1057-58 (D.C. Cir. 1978) (holding that an informal case-by-case
enforcement discretion approach is adequate); but see Marathon Oil Co.
v. EPA, 564 F.2d 1253, 1272-73 (9th Cir. 1977) (requiring a more
formalized approach to consideration of ``upsets beyond the control of
the permit holder.''). Under the EPA's regulatory affirmative defense
provisions, if a source could demonstrate in a judicial or
administrative proceeding that it had met the requirements of the
affirmative defense in the regulation, civil penalties would not be
assessed. Recently, the United States Court of Appeals for the District
of Columbia Circuit vacated such an affirmative defense in one of the
EPA's section 112(d) regulations. NRDC v. EPA, No. 10-1371 (D.C. Cir.
April 18, 2014) 2014 U.S. App. LEXIS 7281 (vacating affirmative defense
provisions in a section 112(d) rule establishing emission standards for
Portland cement kilns). The court found that the EPA lacked authority
to establish an affirmative defense for private civil suits and held
that under the CAA, the authority to determine civil penalty amounts
lies exclusively with the courts, not the EPA. Specifically, the Court
found: ``As the language of the statute makes clear, the courts
determine, on a case-by-case basis, whether civil penalties are
`appropriate.''' See NRDC, 2014 U.S. App. LEXIS 7281 at *21 (``[U]nder
this statute, deciding whether penalties are `appropriate' in a given
private civil suit is a job for the courts, not EPA.''). In light of
NRDC, the EPA is not including a regulatory affirmative defense
provision in this proposed rule. As explained above, if a source is
unable to comply with emissions standards as a result of a malfunction,
the EPA may use its case-by-case enforcement discretion to provide
flexibility, as appropriate. Further, as the DC Circuit recognized, in
an EPA or citizen enforcement action, the court has the discretion to
consider any defense raised and determine whether penalties are
appropriate. Cf. NRDC, 2014 U.S. App. LEXIS 7281 at *24. (arguments
that violation were caused by unavoidable technology failure can be
made to the courts in future civil cases when the issue arises). The
same logic applies to EPA administrative enforcement actions.
b. Specific SSM-Related Proposed Changes
    To address the United States Court of Appeals for the District of
Columbia Circuit vacatur of portions of the EPA's CAA section 112
regulations governing the emissions of HAP during periods of SSM, we
are proposing revisions and additions to certain provisions of the
OSWRO rule. As described in detail below, we are proposing to revise
the General Provisions applicability table (Table 2 to Subpart DD) in
several of the references related to requirements that apply during
periods of SSM. We are also proposing revisions related to the
following provisions of the OSWRO rule: (1) The general duty to
minimize emissions at all times; (2) the requirement for sources to
comply with the emission limits in the rule at all times, with
clarifications for what constitutes a deviation; (3) performance
testing conditions requirements; (4) excused monitoring excursions
provisions; and (5) malfunction recordkeeping and reporting
requirements.
i. General Duty
    We are proposing to revise the General Provisions table (Table 2)
entry for 40 CFR 63.6(e) by adding rows specifically for 40 CFR
63.6(e)(1)(i), 63.6(e)(1)(ii), 63.6(e)(1)(iii), and 63.6(e)(3) and to
include a ``no'' in the second column for the 40 CFR 63.6(e)(1)(i)
entry. Section 63.6(e)(1)(i) describes the general duty to minimize
emissions. Some of the language in that section is no longer necessary
or appropriate in light of the elimination of the SSM exemption. We are
proposing instead to add general duty regulatory text at 40 CFR
63.683(e) that reflects the

general duty to minimize emissions while eliminating the reference to
periods covered by an SSM exemption. The current language in 40 CFR
63.6(e)(1)(i) characterizes what the general duty entails during
periods of SSM. With the elimination of the SSM exemption, there is no
need to differentiate between normal operations, startup and shutdown,
and malfunction events in describing the general duty. Therefore the
language the EPA is proposing for 40 CFR 63.683(e) does not include
that language from 40 CFR 63.6(e)(1).
    We are also proposing to include a ``no'' in the second column for
the newly added entry for 40 CFR 63.6(e)(1)(ii). Section 63.6(e)(1)(ii)
imposes requirements that are not necessary with the elimination of the
SSM exemption or are redundant with the general duty requirement being
added at 63.683(e).
    The provisions of 40 CFR 63.6(e)(1)(iii) still apply, and we are
keeping the ``yes'' in the second column for that section. For 40 CFR
63.6(e)(2), we are proposing to include a ``no'' in the second column
for that section because it is a reserved section in the General
Provisions.
    We are also proposing to clarify in the applicability section of 40
CFR 63.680(g)(1) and (2) that the emission limits of subpart DD apply
at all times except when the affected source is not operating and that
the owner or operator must not shut down items of equipment required or
used for compliance with the requirements of subpart DD.
ii. SSM Plan
    We are also proposing to include a ``no'' in the second column for
the newly added 40 CFR 63.6(e)(3) entry. Generally, this paragraph
requires development of an SSM plan and specifies SSM recordkeeping and
reporting requirements related to the SSM plan. As noted, the EPA is
proposing to remove the SSM exemptions. Therefore, affected units will
be subject to an emission standard during such events. The
applicability of a standard during such events will ensure that sources
have ample incentive to plan for and achieve compliance and thus the
SSM plan requirements are no longer necessary.
iii. Compliance With Standards
    We are proposing to revise the General Provisions table (Table 2)
entry for 40 CFR 63.6(f)(1) by changing the ``yes'' in column 2 to a
``no.'' The current language of 40 CFR 63.6(f)(1) exempts sources from
non-opacity standards during periods of SSM. As discussed above, the
court in Sierra Club vacated the exemptions contained in this provision
and held that the CAA requires that some section 112 standard apply
continuously. Consistent with Sierra Club, the EPA is proposing to
revise standards in this rule to apply at all times.
iv. Performance Testing
    We are proposing to revise the General Provisions table (Table 2)
entry for 40 CFR 63.7(e)(1) by changing the ``yes'' in column 2 to a
``no.'' Section 63.7(e)(1) describes performance testing requirements.
The EPA is instead proposing to add a performance testing requirement
at 40 CFR 63.694(l). The performance testing requirements we are
proposing to add differ from the General Provisions performance testing
provisions in several respects. The regulatory text does not include
the language in 40 CFR 63.7(e)(1) that restated the SSM exemption.
However, consistent with 40 CFR 63.7(e)(1), performance tests conducted
under this subpart should be based on representative performance (i.e.,
performance based on normal operating conditions) of the affected
source. The EPA is proposing to add language that requires the owner or
operator to record the process information that is necessary to
document operating conditions during the test and include in such
record an explanation to support that such conditions represent normal
operation. Section 63.7(e) requires that the owner or operator make
available to the Administrator such records ``as may be necessary to
determine the condition of the performance test'' upon request, but
does not specifically require the information to be recorded. The
regulatory text the EPA is proposing to add to this provision builds on
that requirement and makes explicit the requirement to record the
information.
v. Monitoring
    We are proposing to revise the General Provisions table (Table 2)
entries for 40 CFR 63.8(c)(1)(i) and (iii) by changing the ``yes'' in
column 2 to a ``no.'' The cross-references to the general duty and SSM
plan requirements in those subparagraphs are not necessary in light of
other requirements of 40 CFR 63.8 that require good air pollution
control practices (40 CFR 63.8(c)(1)) and that set out the requirements
of a quality control program for monitoring equipment (40 CFR 63.8(d)).
vi. Recordkeeping
    We are proposing to revise the General Provisions table (Table 2)
entry for 40 CFR 63.10(b)(2)(i) by changing the ``yes'' in column 2 to
a ``no.'' Section 63.10(b)(2)(i) describes the recordkeeping
requirements during startup and shutdown. These recording provisions
are no longer necessary because the EPA is proposing that recordkeeping
and reporting applicable to normal operations will apply to startup and
shutdown. In the absence of special provisions applicable to startup
and shutdown, such as a startup and shutdown plan, there is no reason
to retain additional recordkeeping for startup and shutdown periods.
    We are proposing to revise the General Provisions table (Table 2)
entry for 40 CFR 63.10(b)(2)(ii) by changing the ``yes'' in column 2 to
a ``no.'' Section 63.10(b)(2)(ii) describes the recordkeeping
requirements during a malfunction. The EPA is proposing to add such
requirements to 40 CFR 63.696(h). The regulatory text we are proposing
to add differs from the General Provisions it is replacing in that the
General Provisions require the creation and retention of a record of
the occurrence and duration of each malfunction of process, air
pollution control, and monitoring equipment. The EPA is proposing that
this requirement apply to any failure to meet an applicable standard
and is requiring that the source record the date, time, and duration of
the failure rather than the ``occurrence.'' The EPA is also proposing
to add to 40 CFR 63.696(h) a requirement that sources keep records that
include a list of the affected source or equipment and actions taken to
minimize emissions, an estimate of the volume of each regulated
pollutant emitted over the standard for which the source failed to meet
the standard, and a description of the method used to estimate the
emissions. Examples of such methods would include product-loss
calculations, mass balance calculations, measurements when available,
or engineering judgment based on known process parameters. The EPA is
proposing to require that sources keep records of this information to
ensure that there is adequate information to allow the EPA to determine
the severity of any failure to meet a standard, and to provide data
that may document how the source met the general duty to minimize
emissions when the source has failed to meet an applicable standard.
    We are proposing to revise the General Provisions table (Table 2)
entry for 40 CFR 63.10(b)(2)(iv) by changing

the ``yes'' in column 2 to a ``no.'' When applicable, the provision
requires sources to record actions taken during SSM events when actions
were inconsistent with their SSM plan. The requirement is no longer
appropriate because SSM plans will no longer be required. The
requirement previously applicable under 40 CFR 63.10(b)(2)(iv)(B) to
record actions to minimize emissions and record corrective actions is
now applicable by reference to 40 CFR 63.696(h).
    We are proposing to revise the General Provisions table (Table 2)
entry for 40 CFR 63.10(b)(2)(v) by changing the ``yes'' in column 2 to
a ``no.'' When applicable, the provision requires sources to record
actions taken during SSM events to show that actions taken were
consistent with their SSM plan. The requirement is no longer
appropriate because SSM plans will no longer be required.
vii. Reporting
    We are proposing to revise the General Provisions table (Table 2)
entry for 40 CFR 63.10(d)(5)(i) by consolidating it with the entry for
63.10(d)(5)(ii) and changing the ``yes'' in column 2 to ``no.'' Section
63.10(d)(5)(i) describes the reporting requirements for startups,
shutdowns, and malfunctions. To replace the General Provisions
reporting requirements, the EPA is proposing to add reporting
requirements to 40 CFR 63.697(b)(3). The replacement language differs
from the General Provisions requirement in that it eliminates periodic
SSM reports as a stand-alone report. We are proposing language that
requires sources that fail to meet an applicable standard at any time
to report the information concerning such events in the semi-annual
summary report already required under this rule. We are proposing that
the report must contain the number, date, time, duration, and the cause
of such events (including unknown cause, if applicable), a list of the
affected source or equipment, an estimate of the quantity of each
regulated pollutant emitted over any emission limit, and a description
of the method used to estimate the emissions.
    Examples of such methods would include product-loss calculations,
mass balance calculations, measurements when available, or engineering
judgment based on known process parameters. The EPA is proposing this
requirement to ensure that there is adequate information to determine
compliance, to allow the EPA to determine the severity of the failure
to meet an applicable standard, and to provide data that may document
how the source met the general duty to minimize emissions during a
failure to meet an applicable standard.
    We will no longer require owners or operators to determine whether
actions taken to correct a malfunction are consistent with an SSM plan,
because plans would no longer be required. The proposed amendments
therefore eliminate the cross reference to 40 CFR 63.10(d)(5)(i) that
contains the description of the previously required SSM report format
and submittal schedule from this section. These specifications are no
longer necessary because the events will be reported in otherwise
required reports with similar format and submittal requirements.
    We are proposing to revise the General Provisions table (Table 2)
entry for 40 CFR 63.10(d)(5)(ii) by consolidating it with the entry for
63.10(d)(5)(i) and changing the ``yes'' in column 2 to a ``no.''
Section 63.10(d)(5)(ii) describes an immediate report for startups,
shutdown, and malfunctions when a source failed to meet an applicable
standard but did not follow the SSM plan. We will no longer require
owners and operators to report when actions taken during a startup,
shutdown, or malfunction were not consistent with an SSM plan, because
plans would no longer be required.
2. Electronic Reporting
    In this proposal, the EPA is describing a process to increase the
ease and efficiency of performance test data submittal while improving
data accessibility. Specifically, the EPA is proposing that owners and
operators of OSWRO facilities submit electronic copies of required
performance test reports by direct computer-to-computer electronic
transfer using EPA-provided software. The direct computer-to-computer
electronic transfer is accomplished through the EPA's Central Data
Exchange (CDX) using the Compliance and Emissions Data Reporting
Interface (CEDRI). The Central Data Exchange is EPA's portal for
submittal of electronic data. The EPA-provided software is called the
Electronic Reporting Tool (ERT) which is used to generate electronic
reports of performance tests and evaluations. The ERT generates an
electronic report package which will be submitted using the CEDRI. The
submitted report package will be stored in the CDX archive (the
official copy of record) and EPA's public database called WebFIRE. All
stakeholders will have access to all reports and data in WebFIRE and
accessing these reports and data will be very straightforward and easy
(see the WebFIRE Report Search and Retrieval link at http://cfpub.epa.gov/webfire/index.cfm?action=fire.searchERTSubmission). A
description and instructions for use of the ERT can be found at http://www.epa.gov/ttn/chief/ert/index.html and CEDRI can be accessed through
the CDX Web site (www.epa.gov/cdx). A description of the WebFIRE
database is available at: http://cfpub.epa.gov/oarweb/index.cfm?action=fire.main.
    The proposal to submit performance test data electronically to the
EPA applies only to those performance tests conducted using test
methods that are supported by the ERT. The ERT supports most of the
commonly used EPA reference methods. A listing of the pollutants and
test methods supported by the ERT is available at: http://www.epa.gov/ttn/chief/ert/index.html.
    We believe that industry would benefit from this proposed approach
to electronic data submittal. Specifically, by using this approach,
industry will save time in the performance test submittal process.
Additionally, the standardized format that the ERT uses allows sources
to create a more complete test report resulting in less time spent on
data backfilling if a source failed to include all data elements
required to be submitted. Also through this proposal industry may only
need to submit a report once to meet the requirements of the applicable
subpart because stakeholders can readily access these reports from the
WebFIRE database. This also benefits industry by cutting back on
recordkeeping costs as the performance test reports that are submitted
to the EPA using CEDRI are no longer required to be retained in hard
copy, thereby, reducing staff time needed to coordinate these records.
    Since the EPA will have performance test data in hand, we expect
that there may be fewer or less substantial data collection requests in
conjunction with prospective required residual risk assessments or
technology reviews. This would result in a decrease in staff time
needed to respond to data collection requests.
    State, local and tribal air pollution control agencies (S/L/Ts) may
also benefit from having electronic versions of the reports they are
now receiving. For example, S/L/Ts may be able to conduct a more
streamlined and accurate review of electronic data submitted to them.
For example, the ERT would allow for an electronic review process,
rather than a manual data assessment, therefore, making review and
evaluation of the source provided data and calculations easier and more
efficient. In addition, the public stands to benefit from electronic

reporting of emissions data because the electronic data will be easier
for the public to access. How the air emissions data are collected,
accessed and reviewed will be more transparent for all stakeholders.
    One major advantage of the proposed submittal of performance test
data through the ERT is a standardized method to compile and store much
of the documentation required to be reported by this rule. The ERT
clearly states what testing information would be required by the test
method and has the ability to house additional data elements that might
be required by a delegated authority.
    In addition the EPA must have performance test data to conduct
effective reviews of CAA sections 111, 112 and 129 standards, as well
as for many other purposes including compliance determinations,
emission factor development and annual emission rate determinations. In
conducting these required reviews, the EPA has found it ineffective and
time consuming, not only for us, but also for regulatory agencies and
source owners and operators, to locate, collect and submit performance
test data. In recent years, though, stack testing firms have typically
collected performance test data in electronic format, making it
possible to move to an electronic data submittal system that would
increase the ease and efficiency of data submittal and improve data
accessibility.
    A common complaint heard from industry and regulators is that
emission factors are outdated or not representative of a particular
source category. With timely receipt and incorporation of data from
most performance tests, the EPA would be able to ensure that emission
factors, when updated, represent the most current range of operational
practices. Finally, another benefit of the proposed data submittal to
WebFIRE electronically is that these data would greatly improve the
overall quality of existing and new emissions factors by supplementing
the pool of emissions test data for establishing emissions factors.
    In summary, in addition to supporting regulation development,
control strategy development and other air pollution control
activities, having an electronic database populated with performance
test data would save industry, state, local, tribal agencies and the
EPA significant time, money and effort, while also improving the
quality of emission inventories and air quality regulations.
3. Routine Maintenance
    40 CFR 63.693(b)(3)(i) of the OSWRO NESHAP allows for control
devices to be bypassed to perform planned routine maintenance of the
closed-vent system or control device in situations when the routine
maintenance cannot be performed during periods that the emission point
vented to the control device is shut down. The facility is allowed to
bypass the control device for up to 240 hours per year.
    The routine maintenance provision was originally established in the
Hazardous Organic NESHAP (HON) (see 40 CFR 63.119(e)(3)-(4); 57 FR
62710, December 31, 1992 (proposed); 59 FR 19402, April 22, 1994
(final)) for facilities that elected to use a closed vent system and
control device to comply with the emission limitation requirements for
tanks. We included the routine maintenance provision in the HON for
tanks routing emissions to control devices because the estimated HAP
emissions to degas the tank would be greater than the emissions that
would result if the tank emitted directly to the atmosphere for a short
period of time during routine maintenance of the control device.
    We intended for the OSWRO NESHAP to track the HON maintenance
provisions, and as such, those provisions should have been limited to
tanks. We have not identified a basis for applying the routine
maintenance provisions in the OSWRO NESHAP to emission points other
than tanks. Therefore, we are proposing to limit the provision to tanks
routing emissions to a control device, consistent with the rationale
provided in the HON. We request comment on this proposed revision.
4. Open-Ended Valves and Lines
    The OSWRO NESHAP at 40 CFR 63.691(b) requires an owner or operator
to control emissions from equipment leaks according to the requirements
of either 40 CFR part 61, subpart V or 40 CFR part 63, subpart H. For
open-ended valves and lines, both subpart V in Sec.  61.242-6(a) and
subpart H in Sec.  63.167(a) require that the open end be equipped with
a cap, blind flange, plug, or second valve that shall ``seal the open
end.'' However, ``seal'' is not defined in either subpart, leading to
uncertainty for the owner or operator as to whether compliance is being
achieved. Inspections under the EPA's Air Toxics LDAR initiative have
provided evidence that while certain open-ended lines may be equipped
with a cap, blind flange, plug or second valve, these are not providing
a ``seal'' as the EPA interprets the term.\25\
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    \25\ See ``Region V OEL data for VV rulemaking'' available in
the docket for this action.
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    In response to this uncertainty, we are proposing to amend 40 CFR
63.691(a) to clarify what ``seal the open end'' means for open-ended
valves and lines. This proposed clarification explains that, for the
purpose of complying with the requirements of 40 CFR 63.167 of subpart
H, open-ended valves and lines are ``sealed'' by the cap, blind flange,
plug, or second valve instrument monitoring of the open-ended valve or
line conducted according to Method 21 of 40 CFR part 60, appendix A
indicates no readings of 500 ppm or greater.
    In addition, 40 CFR 63.167(d) of subpart H and 40 CFR 61.242-6(d)
of subpart V exempt open-ended valves and lines that are in an
emergency shutdown system, and which are designed to open
automatically, from the requirements to be equipped with a cap, blind
flange, plug, or second valve that seals the open end. We are proposing
that these open-ended valves and lines follow the requirements of 40
CFR 63.693(c)(2) for bypass devices that could be used to divert a vent
stream from the closed-vent system to the atmosphere, which would
require that each such open-ended line be equipped with either a flow
indicator or a seal or locking device. We are also proposing
recordkeeping and reporting requirements in 40 CFR 63.696(j)(2) and 40
CFR 63.697(b)(6) for these open-ended values and lines.
    We solicit comments on our proposed approach to reducing the
compliance uncertainty associated with ``sealed'' open-ended valves and
lines and our proposed requirements for open-ended valves and lines
that are in an emergency shutdown system and are designed to open
automatically.
5. Safety Devices, Pressure Tanks, Bypasses and PRDs
    The OSWRO MACT standards contain requirements for safety devices,
closure devices on pressure tanks, PRDs and bypasses, established with
the recognition that emission releases to the atmosphere from these
devices and from bypasses of control equipment occur only in the event
of unplanned and unpredictable events. While emissions vented to the
atmosphere in these events may contain HAP that would otherwise be
subject to the OSWRO MACT emission standards, the OSWRO MACT rule
followed the EPA's former practice prior to the Sierra Club decision of
exempting malfunction events from otherwise applicable

emissions standards. Consequently, as these events were assumed to
occur during malfunctions, the OSWRO MACT standards did not restrict
emissions of HAP from these equipment or events to the atmosphere.
    In the Sierra Club decision, the Court determined that the SSM
exemption violated the CAA and vacated the regulatory provisions in the
General Provisions containing the exemption. See section IV.D.1 of this
preamble for additional discussion. To ensure the OSWRO MACT standards
are consistent with the Court's action, we are proposing to remove the
SSM exemption from the rule. In addition, in order for our treatment of
malfunction-caused releases to the atmosphere to conform with the
reasoning of the Court's ruling, we are proposing to add a provision
that releases of HAP listed in Table 1 of 40 CFR part 63, subpart DD
directly to the atmosphere from PRDs and closure devices on pressure
tanks in off-site material service are prohibited. We are also
proposing to prohibit bypasses that divert a process vent or closed
vent system stream to the atmosphere such that it does not first pass
through an emission control device, except to perform planned routine
maintenance of the closed-vent system or emission control device for
tanks, as discussed in section IV.D.3 of this preamble. We are further
proposing to require owners or operators to keep records and report any
bypass and the amount of HAP released to the atmosphere with the next
periodic report. In addition, to add clarity to these proposed
provisions, we are proposing to add definitions for ``bypass,''
``pressure release,'' ``pressure relief device or valve,'' ``in gas/
vapor service,'' ``in light liquid service'' ``in heavy liquid
service'' and ``in liquid service'' to 40 CFR part 63, subpart DD. We
are also proposing to remove the definition of ``safety device'' and
the provisions related to safety devices from 40 CFR part 63, subpart
DD, which would overlap with and be redundant of parts of the proposed
definition of ``pressure relief device or valve'' and the provisions
related to these devices. To our knowledge, pressure relief devices or
valves are the only safety devices used in OSWRO processes.
    To address potential releases from PRDs, we are also proposing to
require facility owners or operators subject to the OSWRO MACT
standards to employ monitoring of PRDs in off-site material service
using a device or monitoring system that is capable of: (1) Identifying
the pressure release; (2) recording the time and duration of each
pressure release; and (3) notifying operators immediately that a
pressure release is occurring. We are further proposing to require
owners or operators to keep records and report any pressure release and
the amount of HAP released to the atmosphere with the next periodic
report.
    Pressure releases to the atmosphere from PRDs in off-site material
service have the potential to emit large quantities of HAP. Where a
release occurs, it is important to identify and mitigate it as quickly
as possible. We recognize that releases from PRDs sometimes occur in
order to protect systems from failures that could endanger worker
safety and the systems that the PRDs are designed to protect. We have
provided a balanced approach designed to minimize HAP emissions while
recognizing that these events may be unavoidable even in a well-
designed and maintained system. For purposes of estimating the costs of
this requirement, we assumed that operators would install electronic
indicators on each relief device that vents to the atmosphere to
identify and record the time and duration of each pressure release.
However, we are proposing that owners and operators could choose to use
an existing system, such as a parameter monitoring system, as long as
it is sufficient to identify a pressure release, notify operators
immediately that a release is occurring and record the time and
duration of the release.
    Based on our cost assumptions, the nationwide capital cost of
installing these monitors for the OSWRO industry is approximately $1.75
million and the annualized cost of installing and operating these
monitors is $250,000 per year. As noted above, the owner or operator
may use parameter monitoring systems already in place. Therefore, our
costs based on the installation of electronic indicators on each relief
device that vents to the atmosphere is conservative and likely
overstates the costs.
6. Performance Test Method Clarifications and Alternative Methods
    The OSWRO NESHAP at 40 CFR 63.694 specifies test methods and
procedures to be used in determining compliance with the requirements
of subpart DD. We are proposing several minor changes to these
provisions to correct errors and to provide consistency, clarification
and flexibility.
    We are proposing several minor clarifications to align the testing
requirements with standard testing practices. We are proposing that
test runs last ``at least 1 hour'', rather than stating that tests last
``1 hour'' in Sec.  63.694(f)(1) and (i)(1). This is consistent with
standard testing practice and other provisions of the rule that specify
a minimum sampling time instead of an absolute sampling time. Requiring
a minimum sampling time allows owners and operators to conduct longer
sampling runs when necessary. For example, an owner or operator may
conduct longer sampling runs to achieve a lower detection limit for a
specific compound. We are proposing to specify that a minimum of three
test runs are required in Sec.  63.694(l)(3)(i) and (l)(4)(i),
consistent with the Part 63 General Provisions and standard testing
practices. We are proposing to specify in Sec.  63.694(m)(2) that in
the determination of process vent stream flow rate and total HAP
concentration, the sample site selected must be at the center of the
vent for vents smaller than 0.10 meter in diameter. EPA Methods 1 and
1A do not apply to stack diameters smaller than 0.10 meter in diameter,
and the regulation as currently written states that it is unnecessary
to traverse vents less than 0.10 meter in diameter, but is unclear on
how sampling point selection must be chosen. We are proposing to
clarify that the sampling point must be at the center of the vent; this
sample point is the point most likely to provide a representative
sample of the gas stream.
    To provide consistency with other parts of the OSWRO MACT
standards, we are proposing to clarify the requirements of Sec.
63.694(j)(3) for determining the maximum HAP vapor pressure for off-
site material in a tank if the Administrator and the owner or operator
disagree on a determination of the maximum HAP vapor pressure for an
off-site material stream using knowledge. We are proposing that results
from direct measurement of the HAP vapor pressure must be used in these
instances. This is consistent with Sec.  63.694(b)(3)(iv), which uses
the same language for VOHAP measurements.
    We also are proposing to correct a citation in Sec.  63.694(k)(3).
The regulation currently references the wrong section of Method 21 for
instrument response factors. The appropriate section in EPA Method 21
is 8.1.1, not 3.1.2(a).
    We are proposing to allow the use of either EPA Method 25A or
Method 18 in Sec.  63.694(l)(3) and (4). We are clarifying that Method
25A must be used for determining compliance with the enclosed
combustion device total organic compound (TOC) limit, while Method 18
is used for determining compliance with the total HAP concentration
limit. We are making this change because Method 25A is a flame
ionization method that measures concentration as carbon equivalents. It

is preferred over Method 18 for the measurement of TOC. Method 18 is
used to determine the concentration of individual compounds, making it
appropriate for measuring individual HAPs that can be summed and
compared with the total HAP limit, especially when a finite list of
HAPs is specified (such as in Table 1 of the OSWRO NESHAP). Because TOC
includes all organic compounds (minus methane and ethane) and Method 18
requires a set list of individual compounds to be measured. In order to
use Method 18 for TOC measurements, one would have to know every
organic compound in the gas stream and analyze each individually, which
is a difficult and nearly impossible task in most cases. Therefore, we
are proposing that TOC is to be measured with Method 25A and total HAP
is to be measured with Method 18. The changes in how the test methods
are applied and how TOC is most appropriately measured result in
changes in some of the equations in Sec.  63.694 as well.
    We are proposing additional flexibility in some of the test methods
that are allowed by the OSWRO NESHAP. We are including the use of EPA
Method 3A as an alternative to EPA Method 3B in Sec.
63.694(l)(4)(iii)(A) for determining the oxygen concentration to use in
oxygen correction equations. EPA Method 3A is just as effective as EPA
Method 3B in determining oxygen concentration. We have also included
the use of EPA Methods 2F and 2G as options for flow rate measurement
in Sec.  63.694(l)(2) and (m)(3). These methods are newer velocity
measurement methods that were published after the original OSWRO rule.
By allowing these test method alternatives in the rule, we are
providing greater flexibility to sources and easing the burden on
sources and delegated agencies by reducing the number of potential
alternative method requests.
7. Other Clarifications and Corrections
    We are proposing several miscellaneous minor changes to improve the
clarity of the rule requirements. These proposed changes include:
     Updating the list in Sec.  63.684(b)(5) of combustion
devices that may be used to destroy the HAP contained in an off-site
material stream, to include incinerators, boilers or industrial
furnaces for which the owner or operator complies with the requirements
of 40 CFR part 63, subpart EEE. Where the OSWRO MACT standards
currently require that combustion devices used for the purposes of
compliance with the OSWRO MACT standards must be regulated under
various subparts of RCRA, many of these units now comply with 40 CFR
part 63, subpart EEE, which had not been promulgated when the OSWRO
MACT standards were developed. We are also proposing conforming changes
to the boiler and process heater control device requirements in Sec.
63.693(g)(1)(v). These changes clarify that combustion units complying
with the requirements of subpart EEE may be used for the purposes of
compliance with the OSWRO MACT standards.
     Revising the tank control level tables and the text in
Sec.  63.685(b) to clarify the control level required for tanks of any
capacity (effectively those less than 75 m\3\) with a vapor pressure of
76.6 kPa or greater. Tanks meeting these capacity and vapor pressure
thresholds are not included in the control level tables referred to in
Sec.  63.685(b), currently Tables 3 and 4 of the OSWRO NESHAP, and
instead text is included in Sec.  63.685(b)(4) for these tanks. To
clarify the requirements for these tanks, we are proposing to specify
the requirements for these tanks in the tank control level tables
(proposed Tables 3, 4 and 5) and remove the text in Sec.  63.685(b)(4).
     Clarifying that where Sec.  63.691 requires the owner or
operator to control the HAP emitted from equipment leaks in accordance
with either 40 CFR part 61, subpart V or 40 CFR part 63, subpart H, the
definitions in 40 CFR 61.241 and 40 CFR 63.161 apply, with the
differences listed, for the purposes of the OSWRO NESHAP.
     Clarifying the requirement of Sec.  63.683(c)(1)(ii) that
the average VOHAP concentration of the off-site material must be less
than 500 ppmw at the point-of-delivery and clarifying the requirements
of Sec.  63.693(f)(1)(i)(B) and Sec.  63.693(f)(1)(ii)(B) are to
achieve a total incinerator outlet concentration of less than or equal
to 20 ppmv on a dry basis corrected to 3 percent oxygen. Due to
clerical errors, the ppm values of these requirements are not in the
current OSWRO NESHAP, and we are proposing to insert them.
     Clarifying in Sec. Sec.  63.684(h), 63.693(b)(8) and
63.694(b)(3)(iv) that the Administrator may require a performance test,
revisions to a control device design analysis, or that direct
measurement be used in the determination of a VOHAP concentration,
rather than that the Administrator may only request such actions.
     Revising several references to the Part 63 General
Provisions in Table 2 to correct errors, including errors where the
entries in Table 2 conflict with the regulatory text in subpart DD and
where references to specific sections of the General Provisions do not
exist or are reserved.
8. Flare Performance
    In addition to our proposed actions discussed above, we are seeking
comments on the performance of flares used to control HAP emissions in
this source category, as governed by the EPA's General Provisions at 40
CFR 63.11(b). In April 2012, the EPA conducted an external peer review
of a draft technical report, ``Parameters for Properly Designed and
Operated Flares'' (http://www.epa.gov/ttn/atw/flare/2012flaretechreport.pdf) (``draft flare technical report''). In this
report, the EPA evaluated test data and identified a variety of
parameters that may affect flare performance and that could be
monitored to help ensure good combustion efficiency. Based on feedback
received from the external ad-hoc peer review panel, the EPA has since
undertaken an initiative to re-evaluate parameters that may affect
overall flare performance at source categories known to use flares for
controlling HAP emissions (e.g., petroleum refining).
    Currently, OSWRO sources may choose from a variety of control
techniques to control emissions from this source category. One option
is to operate a flare to reduce HAP emissions in accordance with the
provision in 40 CFR 63.693(h). However, responses to the CAA section
114 questionnaire indicate that flares are not commonly used as control
devices for this source category, and we know of only one facility that
uses a flare as a primary control device in order to comply with the
OSWRO NESHAP. In addition, none of the flare performance data used in
the draft flare technical report comes from OSWRO sources nor does it
provide any test data on non-assisted flare types, which based on
available information, is the only flare type found in the OSWRO source
category. As indicated in the EPA flare draft technical report, one of
the primary factors that affects flare performance is over-assisting
flares with too much steam or air and while this can potentially occur
in steam-assisted and air-assisted flare designs, non-assisted flare
types do not have a potential to over-assist. Thus, we have no
information to suggest that flares at OSWRO sources are achieving poor
destruction efficiency. We solicit comments on our discussion and
conclusions regarding flare performance, including additional
information on flare performance related to this source category.

Examples of types of information we seek from commenters regarding
flares for the OSWRO source category include: Frequency of flaring;
number and types of flares used; waste gas characteristics such as flow
rate, composition and heat content; assist gas characteristics such as
target assist gas to waste gas ratios and minimum assist gas flow
rates; use of flare gas recovery and other flare minimization
practices; and existing flare monitoring systems.

E. What compliance dates are we proposing?

    Under CAA section 112(d), the proposed compliance date for new and
existing affected sources for the revised SSM requirements, electronic
reporting requirements, the revised routine maintenance provisions, the
operating and pressure release management requirements for PRDs, and
the revised requirements regarding bypasses and closure devices on
pressure tanks is the effective date of the final amendments. We are
proposing this compliance date because available information indicates
these new and revised requirements should be immediately implementable
by the facilities.
    We are also proposing that for existing affected sources subject to
the OSWRO MACT standards, the compliance date for the PRD monitoring
requirements is 3 years from the effective date of the final
amendments. This time is needed regardless of whether an owner or
operator of a facility chooses to comply with the PRD monitoring
provisions by installing PRD release indicator systems and alarms,
employing parameter monitoring, routing releases to a control device,
or choosing another compliance option as permitted under the proposed
provisions. This time period will allow OSWRO facility owners and
operators to research equipment and vendors, and to purchase, install,
test and properly operate any necessary equipment by the compliance
date. For new affected sources, the proposed compliance date for PRD
monitoring requirements is the effective date of the final amendments.
    Finally, we are proposing revised requirements for equipment leaks
and tanks under CAA sections 112(d)(6) and (f)(2). The compliance
deadlines for standards developed under CAA section 112(f)(2) are
addressed in CAA sections 112(f)(3) and (4). As provided in CAA Section
112(f)(4), risk standards shall not apply to existing affected sources
until 90 days after the effective date of the rule, but the
Administrator may grant a waiver for a particular source for a period
of up to 2 years after the effective date. Here, the EPA is already
aware of the steps needed for OSWRO facilities to comply with the
proposed standards for equipment leaks and tanks and to reasonably
estimate the amount of time it will take these facilities to do so.
Therefore, consistent with CAA section 112(f)(4)(B), we are proposing
that a two-year compliance period is necessary for the revised tank
requirements to allow affected facilities to research equipment and
vendors, purchase, install, test and properly operate any necessary
equipment by the compliance date. We are also proposing, consistent
with CAA section 112(f)(4)(B), that a one-year compliance period is
necessary for the revised equipment leak requirements to allow affected
facilities that are currently complying with 40 CFR part 61, subpart V
adequate time to purchase, install and test any necessary equipment and
modify their existing LDAR programs. In addition, pursuant to CAA
section 112(d)(6), we are proposing these same compliance dates for the
revised tank and equipment leak standards. For new affected sources,
the proposed compliance date for the revised tank and equipment leak
standards is the effective date of the final amendments.

V. Summary of Cost, Environmental and Economic Impacts

A. What are the affected sources?

    We estimate that there are approximately 52 major source OSWRO
facilities. Based on available permit information, seven facilities are
known to be exempt from most of the rule requirements due to the low
HAP content of the off-site waste they receive or because they comply
instead with 40 CFR part 61, subpart FF, as allowed by the OSWRO
NESHAP, and they are not expected to be affected by the proposed rule
revisions. These facilities are only required to document that the
total annual quantity of the HAP contained in the off-site material
received at the plant site is less than 1 megagram per year, and they
are not subject to any other emissions limits or monitoring, reporting
or recordkeeping requirements. We are not aware of any new OSWRO
facilities that are expected to be constructed in the foreseeable
future.

B. What are the air quality impacts?

    For equipment leaks, we are proposing to eliminate the option of
complying with 40 CFR part 61, subpart V, and requiring facilities in
the OSWRO source category to comply with 40 CFR part 63, subpart H,
including connector monitoring. We estimate the HAP emission reduction
for this change to be approximately 138 tpy. For tanks, we are
proposing to require tanks of certain sizes and containing materials
above certain vapor pressures to use Level 2 controls. We estimate the
HAP emission reduction for this change to be approximately 73 tpy. We
do not anticipate any HAP emission reduction from our proposed
clarification of the rule provision ``seal the open end'' (in the
context of open-ended valves and lines), clarification of the scope of
the routine maintenance provisions, or requirement to electronically
report the results of emissions testing.
    For the proposed revisions to the MACT standards regarding SSM,
including monitoring of PRDs in off-site material service, we were not
able to quantify the possible emission reductions so none are included
in our assessment of air quality impacts.
    Therefore, the estimated total HAP emission reductions for the
proposed rule revisions for the OSWRO source category are estimated to
be 211 tpy.

C. What are the cost impacts?

    For equipment leaks, we are proposing to eliminate the option of
complying with 40 CFR part 61, subpart V, and to require facilities in
the OSWRO source category to comply with 40 CFR part 63, subpart H
(including connector monitoring). We estimate the nationwide capital
costs to be $1.9 million and the annualized costs to be $530,000. For
tanks, we are proposing to require tanks of certain sizes and
containing materials above certain vapor pressures to use Level 2
controls. We estimate the nationwide capital costs to be $76,000 and
the annualized costs to be $21,000. We do not anticipate any
quantifiable capital or annualized costs for our proposed definition of
``seal'' (in the context of open-ended valves and lines), clarification
of the scope of the routine maintenance provisions and requirement to
electronically report the results of emissions testing.
    For the proposed requirements to install and operate monitors on
PRDs, we estimate the nationwide capital costs to be $1.75 million and
the annualized costs to be $250,000.
    Therefore, the total capital costs for the proposed standards for
the OSWRO source category are approximately $3.7 million and the total
annualized costs are approximately $800,000.

D. What are the economic impacts?

    Both the magnitude of control costs needed to comply with a
regulation and the distribution of these costs among affected
facilities can have a role in determining how the market will change in
response to that regulation. Total annualized costs for the proposed

amendments are estimated to be about $800,000. The average annualized
cost per facility is estimated to be about $24,000.
    Without detailed industry data, it is not possible to conduct a
complete quantitative analysis of economic impacts. However, prior
analyses suggest the impacts of these proposed amendments will be
minimal. The Economic Impact Analysis for the Final OSWRO NESHAP \26\
found that demand for off-site waste services was highly inelastic.
This means that suppliers are predominantly able to pass along cost
increases to consumers through higher prices with little, if any,
decrease in the quantity of service demanded. While we do not have
specific information on prices charged or the quantity of service
provided, company revenues are a function of both these factors. The
cost-to-sales ratio is less than one quarter of one percent for all of
the 27 firms included in this analysis, suggesting any increase in
price would be minimal.
---------------------------------------------------------------------------

    \26\ EPA. June 1996.
---------------------------------------------------------------------------

E. What are the benefits?

    We have estimated that this action will achieve HAP emissions
reduction of 211 tons per year. The proposed standards will result in
significant reductions in the actual and MACT-allowable emissions of
HAP and will reduce the actual and potential cancer risks and non-
cancer health effects due to emissions of HAP from this source
category, as discussed in section IV.B.2. We have not quantified the
monetary benefits associated with these reductions; however, these
avoided emissions will result in improvements in air quality and
reduced negative health effects associate with exposure to air
pollution of these emissions.

VI. Request for Comments

    We are soliciting comments on all aspects of this proposed action.
In addition to general comments on this proposed action, we are also
interested in any additional data that may help to improve the risk
assessments and other analyses. We are specifically interested in
receiving any improvements to the data used in the site-specific
emissions profiles used for risk modeling. Such data should include
supporting documentation in sufficient detail to allow characterization
of the quality and representativeness of the data or information.
Section VII of this preamble provides more information on submitting
data.

VII. Submitting Data Corrections

    The site-specific emissions profiles used in the source category
risk and demographic analyses and instructions are available for
download on the RTR Web page at http://www.epa.gov/ttn/atw/rrisk/rtrpg.html. The data files include detailed information for each HAP
emissions release point for the facilities included in the source
category.
    If you believe that the data are not representative or are
inaccurate, please identify the data in question, provide your reason
for concern and provide any ``improved'' data that you have, if
available. When you submit data, we request that you provide
documentation of the basis for the revised values to support your
suggested changes. To submit comments on the data downloaded from the
RTR page, complete the following steps:
    1. Within this downloaded file, enter suggested revisions to the
data fields appropriate for that information.
    2. Fill in the commenter information fields for each suggested
revision (i.e., commenter name, commenter organization, commenter email
address, commenter phone number and revision comments).
    3. Gather documentation for any suggested emissions revisions
(e.g., performance test reports, material balance calculations).
    4. Send the entire downloaded file with suggested revisions in
Microsoft[supreg] Access format and all accompanying documentation to
Docket ID No. EPA-HQ-OAR-2012-0360 (through one of the methods
described in the ADDRESSES section of this preamble).
    5. If you are providing comments on a single facility or multiple
facilities, you need only submit one file for all facilities. The file
should contain all suggested changes for all sources at that facility.
We request that all data revision comments be submitted in the form of
updated Microsoft[supreg] Excel files that are generated by the
Microsoft[supreg] Access file. These files are provided on the RTR Web
page at: http://www.epa.gov/ttn/atw/rrisk/rtrpg.html.

VIII. Statutory and Executive Order Reviews

A. Executive Order 12866: Regulatory Planning and Review and Executive
Order 13563: Improving Regulation and Regulatory Review

    This action is not a ``significant regulatory action'' under the
terms of Executive Order 12866 (58 FR 51735, October 4, 1993) and is
therefore not subject to review under Executive Orders 12866 and 13563
(76 FR 3821, January 21, 2011).

B. Paperwork Reduction Act

    The information collection requirements in this proposed rule have
been submitted for approval to OMB under the Paperwork Reduction Act,
44 U.S.C. 3501, et seq. The Information Collection Request (ICR)
document prepared by the EPA has been assigned the EPA ICR number
1717.10.
    The information requirements are based on notification,
recordkeeping and reporting requirements in the NESHAP General
Provisions (40 CFR part 63, subpart A), which are mandatory for all
operators subject to national emissions standards. These recordkeeping
and reporting requirements are specifically authorized by CAA section
114 (42 U.S.C. 7414). All information submitted to the EPA pursuant to
the recordkeeping and reporting requirements for which a claim of
confidentiality is made is safeguarded according to agency policies set
forth in 40 CFR part 2, subpart B.
    We estimate approximately 52 regulated entities are currently
subject to subpart DD; however, five facilities are only subject to
off-site waste HAP content determination requirements and are not
subject to the emissions standards and other requirements of the OSWRO
NESHAP due to the low HAP content of the off-site waste they receive.
Also, two facilities are not subject to the emissions standards and
other requirements of the OSWRO NESHAP because they comply instead with
40 CFR part 61, subpart FF, as allowed by the OSWRO NESHAP. Therefore,
we estimate that there is an annual average of 45 respondents that are
subject to the annual monitoring, reporting and recordkeeping
requirements of the regulation. This is a decrease of 191 regulated
entities from our estimate for the previous ICR (EPA ICR Number
1717.09, OMB Control Number 2060-0313) for the OSWRO source category.
The annual monitoring, reporting and recordkeeping burden for this
collection (averaged over the first 3 years after the effective date of
the standards) for the proposed amended subpart DD, including existing
rule provisions unchanged by this proposal, is estimated to be 45,147
labor hours at a cost of $2.5 million per year. This represents a
decrease of approximately $15 million and 133,000 labor hours from the
previous ICR, due primarily to the reduction in the estimated number of
regulated entities. In order to more accurately assess the change in
burden resulting from these proposed

amendments, we estimate that the burden for each of the 45 facilities
subject to the annual monitoring, reporting and recordkeeping
requirements of the regulations has increased by $6,000 and 92 labor
hours from the previous ICR estimate.
    The total burden for the federal government (averaged over the
first 3 years after the effective date of the standard) is estimated to
be 449 labor hours per year at an annual cost of $20,200. 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 displays a
currently valid OMB control number. The OMB control numbers for the
EPA's regulations in 40 CFR 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, the EPA has established a public docket
for this rule, which includes this ICR, under Docket ID No. EPA-HQ-OAR-
2012-0360. Submit any comments related to the ICR to the EPA and OMB.
See the ADDRESSES section at the beginning of this document for where
to submit comments to the 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
the EPA. Since OMB is required to make a decision concerning the ICR
between 30 and 60 days after July 2, 2014, a comment to OMB is best
assured of having its full effect if OMB receives it by August 1, 2014.
    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 Regulatory Flexibility Act (RFA) generally requires an agency
to prepare a regulatory flexibility analysis of any rule subject to
notice and comment rulemaking requirements under the Administrative
Procedure Act or any other statute unless the agency certifies that the
rule will not have a significant economic impact on a substantial
number of small entities. Small entities include small businesses,
small organizations, and small governmental jurisdictions.
    For purposes of assessing the impacts of this proposed rule on
small entities, small entity is defined as: (1) A small business as
defined by the Small Business Administration's (SBA) regulations at 13
CFR 121.201; (2) a small governmental jurisdiction that is a government
of a city, county, town, school district or special district with a
population of less than 50,000; and (3) a small organization that is
any not-for-profit enterprise that is independently owned and operated
and is not dominant in its field. Facilities in this source category
are not categorized as a single industry and, as a result, cannot be
classified under a single NAICS code category. During the development
of these proposed amendments, the EPA identified 45 facilities affected
by this proposal. These 45 facilities represent 27 firms in 20
industries. These industries and the SBA size standards are shown in
Table 8.

          Table 8--Industries Included in OSWRO Source Category
------------------------------------------------------------------------
        NAICS                  Description           SBA Size standard
------------------------------------------------------------------------
211111...............  Crude Petroleum and         500 employees.
                        Natural Gas Extraction.
221310...............  Water Supply and            $7.0 million annual
                        Irrigation Systems.         receipts.
237310...............  Highway, Street, and        $33.5 million annual
                        Bridge Construction.        receipts.
324110...............  Petroleum Refineries......  1,500 employees.
325180...............  Other Basic Inorganic       1,000 employees.
                        Chemical Manufacturing.
325194...............  Cyclic Crude,               750 employees.
                        Intermediate, and Gum and
                        Wood Chemical
                        Manufacturing.
325199...............  All Other Basic Organic     1,000 employees.
                        Chemical Manufacturing.
325211...............  Plastics Material and       750 employees.
                        Resin Manufacturing.
327310...............  Cement Manufacturing......  750 employees.
331313...............  Alumina Refining and        1,000 employees.
                        Primary Aluminum
                        Production.
333316...............  Photographic and            1,000 employees.
                        Photocopying Equipment
                        Manufacturing.
336411...............  Aircraft Manufacturing....  1,500 employees.
424690...............  Other Chemical and Allied   100 employees.
                        Products Merchant
                        Wholesalers.
561110...............  Office Administrative       $7.0 million annual
                        Services.                   receipts.
562111...............  Solid Waste Collection....  $35.5 million annual
                                                    receipts.
562211...............  Hazardous Waste Treatment   $35.5 million annual
                        and Disposal.               receipts.
562213...............  Solid Waste Combustion and  $35.5 million annual
                        Incinerators.               receipts.
562219...............  Other Nonhazardous Waste    $35.5 million annual
                        Treatment and Disposal.     receipts.
562920...............  Materials Recovery          $19.0 million annual
                        Facilities.                 receipts.
928110...............  National Security \a\.....  n/a.
------------------------------------------------------------------------
\a\ One facility is operated by the U.S. Department of Defense. Small
  business size standards are not established for this sector.

    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. For the
small business screening analysis, the EPA identified the ultimate
parent company (firm) for each facility and obtained firm-level
employment and revenues using various sources, including the American
Business Directory, Hoovers, corporate Web sites and publically
available financial reports. The screening analysis shows that four of
the 27 firms that own facilities in the OSWRO source category can be
classified as small firms using the SBA size standards for their
respective industries. Based on the sales test screening methodology,
all four firms will experience minimal impact, or a cost-to-sales ratio
of 1 percent or less. Details of this analysis can be found in the memo
``Economic Impact Analysis for Risk and Technology Review: Off-site
Waste and Recovery Operations Source Category'' in the docket.
    We continue to be interested in the potential impacts of the
proposed rule on small entities and welcome comments on issues related
to such impacts.

D. Unfunded Mandates Reform Act

    This rule does not contain a federal mandate that may result in
expenditures of $100 million or more for state, local and tribal
governments, in aggregate, or

the private sector in any one year. The total annualized cost of this
rule is estimated to be no more than $800,000 in any one year. Thus,
this proposed rule is not subject to the requirements of sections 202
or 205 of the UMRA.
    This proposed rule is also not subject to the requirements of
section 203 of UMRA because it contains no regulatory requirements that
might significantly or uniquely affect small governments because it
contains no requirements that apply to such governments nor does it
impose obligations upon them.

E. Executive Order 13132: Federalism

    This action does not have federalism implications. It will not have
substantial direct effects on the states, on the relationship between
the national government and the states, or on the distribution of power
and responsibilities among the various levels of government, as
specified in Executive Order 13132. None of the facilities subject to
this action are owned or operated by state governments. Thus, Executive
Order 13132 does not apply to this proposed rule.
    In the spirit of Executive Order 13132, and consistent with the EPA
policy to promote communications between the EPA and State and local
governments, the 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). There are no
Off-Site Waste Recovery Operation facilities that are owned or operated
by tribal governments. Thus, Executive Order 13175 does not apply to
this action. The EPA specifically solicits comment on this proposed
action from tribal officials.

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

    This action is not subject to Executive Order 13045 (62 FR 19885,
April 23, 1997) because it is not economically significant as defined
in Executive Order 12866, and because the agency does not believe the
environmental health risks or safety risks addressed by this action
present a disproportionate risk to children. Because the proposed rule
amendments would result in reduced emissions of HAP and reduced risk to
anyone exposed, the EPA believes that the proposed rule amendments
would provide additional protection to children. The EPA's risk
assessments are included in the docket for this proposed rule.
    The public is invited to submit comments or identify peer-reviewed
studies and data that assess effects of early life exposure to HAP
emitted by OSWRO facilities.

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

    This action is not subject to Executive Order 13211 (66 FR 28355,
May 22, 2001), because it is not a significant regulatory action under
Executive Order 12866.

I. National Technology Transfer and Advancement Act

    Section 12(d) of the National Technology Transfer and Advancement
Act of 1995 (NTTAA), Public Law 104-113 (15 U.S.C. 272 note), directs
the EPA to use voluntary consensus standards (VCS) in its regulatory
activities unless to do so would be inconsistent with applicable law or
otherwise impractical. VCS are technical standards (e.g., materials
specifications, test methods, sampling procedures and business
practices) that are developed or adopted by VCS bodies. NTTAA directs
the EPA to provide Congress, through OMB, explanations when the agency
decides not to use available and applicable VCS.
    This proposed rule involves technical standards. The EPA proposes
to add EPA Methods 2F and 2G to the list of methods allowed to