> \[6560-50-P\]

**ENVIRONMENTAL PROTECTION AGENCY**

**40 CFR Part 63**

**\[EPA-HQ-OAR-2003-0146; FRL- \]**

**RIN 2060-AO55**

**National Emission Standards for Hazardous Air Pollutants From**
**Petroleum Refineries**

**AGENCY**: Environmental Protection Agency (EPA).

**ACTION**: Proposed rule.

**SUMMARY**: This action proposes amendments to the national emission
standards for petroleum refineries to address the risk remaining after
application of the 1995 standards. This action also provides the results
of EPA's 8-year review of developments in practices, processes, and
control technologies that have occurred since the time EPA adopted the
emissions standards. Based on the results of the residual risk and
technology review, this action proposes two options for both wastewater
treatment systems and storage vessels. For wastewater treatment systems,
the first option would not require any additional controls as necessary
to address residual risk or under the technology review. The second
option would require refineries to apply new or additional requirements
for wastewater treatment systems. For storage vessels, the first option
would also not require any additional controls as necessary to address
residual risk or under the technology review and the second option would
require refineries to apply new or additional requirements for storage
vessels. Finally, we are also proposing two options for amendments to
add emissions standards for cooling towers.

**DATES**: Comments must be received on or before \[INSERT DATE 60 DAYS
FROM DATE OF PUBLICATION\].

**ADDRESSES**: Submit your comments, identified by Docket ID No.
EPA-HQ-OAR-2003-0146 (for petroleum refineries), by one of the following
methods:

-   [www.regulations.gov](http://www.regulations.gov/): Follow the
    on-line instructions for submitting comments.

-   E-mail: <a-and-r-Docket@epa.gov>.

-   [Fax]{.underline}: (202) 566-9744.

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-   [Mail]{.underline}: U.S. Postal Service, send comments to: National
    Emission Standards for Hazardous Air Pollutants from Petroleum
    Refineries: Residual Risk Standards Docket, Environmental Protection
    Agency, Air and Radiation Docket and Information Center, Mailcode:
    2822T, 1200 Pennsylvania Avenue, NW, Washington, DC 20460. Please
    include a total of two copies. We request that a separate copy also
    be sent to the contact person identified below (see FOR FURTHER
    INFORMATION CONTACT).

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-   [Hand Delivery]{.underline}: In person or by courier, deliver
    comments to: EPA Docket and Information Center, Public Reading Room,
    EPA West Building, Room 3334, 1301 Constitution Avenue, NW,
    Washington, DC 20004. Such deliveries are accepted only during the
    Docket=s normal hours of operation and special arrangements should
    be made for deliveries of boxed information.

[Instructions]{.underline}: Direct your comments to Docket ID No.
EPA-HQ-OAR-2003-0146. EPA's policy is that all comments received will be
included in the public docket without change and may be made available
online at [www.regulations.gov](http://www.regulations.gov/), including
any personal information provided, unless the comment includes
information claimed to be confidential business information (CBI) or
other information whose disclosure is restricted by statute. Do not
submit information that you consider to be CBI or otherwise protected
through [www.regulations.gov](http://www.regulations.gov/) or e-mail.
The [www.regulations.gov](http://www.regulations.gov/) website is an
"anonymous access" system, which means EPA will not know your identity
or contact information unless you provide it in the body of your
comment. If you send an e-mail comment directly to EPA without going
through [www.regulations.gov](http://www.regulations.gov/), your e-mail
address will be automatically captured and included as part of the
comment that is placed in the public docket and made available on the
Internet. If you submit an electronic comment, EPA recommends that you
include your name and other contact information in the body of your
comment and with any disk or CD-ROM you submit. If EPA cannot read your
comment due to technical difficulties and cannot contact you for
clarification, EPA may not be able to consider your comment. Electronic
files should avoid the use of special characters, any form of
encryption, and be free of any defects or viruses.

[Docket]{.underline}: All documents in the docket are listed in the
[www.regulations.gov](http://www.regulations.gov/) index. Although
listed in the index, some information is not publicly available, e.g.,
CBI or other information whose disclosure is restricted by statute.
Certain other material, such as copyrighted material, will be publicly
available only in hard copy. Publicly available docket materials are
available either electronically in
[www.regulations.gov](http://www.regulations.gov/) or in hard copy at
the National Emission Standards for Hazardous Air Pollutants from
Petroleum Refineries: Residual Risk Standards Docket, Environmental
Protection Agency, EPA West Building, Room 3334, 1301 Constitution Ave.,
NW, Washington, DC. The Public Reading Room is open from 8:30 a.m. to
4:30 p.m., Monday through Friday, excluding legal holidays. The
telephone number for the Public Reading Room is (202) 566-1744, and the
telephone number for the Air and Radiation Docket is (202) 566-1742.

**FOR FURTHER INFORMATION CONTACT**: Mr. Robert Lucas, Office of Air
Quality Planning and Standards, Sector Policies and Programs Division,
Coatings and Chemicals Group (E143-01), Environmental Protection Agency,
Research Triangle Park, North Carolina 27711, telephone number (919)
541-0884; fax number (919) 541-0246; e-mail address:
<lucas.bob@epa.gov>.

**SUPPLEMENTARY INFORMATION**:

**I. General Information**

A. [Does this action apply to me]{.underline}?

The regulated category and entities affected by this proposed action
include:

  -------------------- --------------- -----------------------------------
  **Category**         **NAICS^1^      **Examples of Regulated Entities**
                       Code**          

  Industry . . .       32411           Petroleum refineries located at a
                                       major source that are subject to 40
                                       CFR part 63, subpart CC.

                                       
  -------------------- --------------- -----------------------------------

**^1^** North American Industrial Classification System.

This table is not intended to be exhaustive, but rather provides a guide
for readers regarding entities likely to be regulated by the proposed
rule. To determine whether your facility would be regulated by the
proposed amendments, you should carefully examine the applicability
criteria in 40 CFR 63.100 of subpart CC (National Emission Standards for
Hazardous Air Pollutants From Petroleum Refineries). If you have any
questions regarding the applicability of this action to a particular
entity, contact either the air permit authority for the entity or your
EPA regional representative as listed in 40 CFR 63.13 of subpart A
(General Provisions).

B. [What should I consider as I prepare my comments for
EPA]{.underline}?

Do not submit information containing CBI to EPA through
[www.regulations.gov](http://www.regulations.gov/) or e-mail. Send or
deliver information as CBI only to the following address: Roberto
Morales, OAQPS Document Control Officer (C404-02), Office of Air Quality
Planning and Standards, Environmental Protection Agency, Research
Triangle Park, NC 27711, Attention Docket ID EPA-HQ-OAR-2003-0146 (for
petroleum refineries). Clearly mark the part or all of the information
that you claim to be CBI. For CBI information in a disk or CD ROM that
you mail to EPA, mark the outside of the disk or CD ROM as CBI and then
identify electronically within the disk or CD ROM the specific
information that is claimed as CBI. In addition to one complete version
of the comment that includes information claimed as CBI, a copy of the
comment that does not contain the information claimed as CBI must be
submitted for inclusion in the public docket. Information so marked will
not be disclosed except in accordance with procedures set forth in 40
CFR part 2.

C. [Where can I get a copy of this document]{.underline}?

In addition to being available in the docket, an electronic copy of this
proposed action will also be available on the Worldwide Web through the
Technology Transfer Network (TTN). Following signature, a copy of this
proposed action will be posted on the TTN=s policy and guidance page for
newly proposed or promulgated rules at the following address:
[http://www.epa.gov/ttn/oarpg/]{.underline}. The TTN provides
information and technology exchange in various areas of air pollution
control.

D. [When would a public hearing occur]{.underline}?

If anyone contacts EPA requesting to speak at a public hearing
concerning the proposed amendments by \[INSERT DATE 15 DAYS FROM DATE OF
PUBLICATION\], we will hold a public hearing on \[INSERT DATE 30 DAYS
FROM DATE OF PUBLICATION\]. If you are interested in attending the
public hearing, contact Bob Lucas at (919) 541-0884 to verify that a
hearing will be held. If a public hearing is held, it will be held at 10
a.m. at the EPA's Environmental Research Center Auditorium, Research
Triangle Park, NC, or an alternate site nearby.

E. [How is this document organized]{.underline}?

I. General Information

A. Does this action apply to me?

B. What should I consider as I prepare my comments to EPA?

C. Where can I get a copy of this document?

D. When would a public hearing occur?

E. How is this document organized?

II\. Background Information

A. What is the statutory authority for regulating hazardous

air pollutants?

B. What source category is affected by this action?

C. What are the emissions sources at petroleum refineries?

D. What hazardous air pollutants are emitted from petroleum

refineries?

E. What does the NESHAP require?

III\. Summary of Proposed Amendments to NESHAP for Petroleum Refineries

A. What options are we proposing?

B. What are the proposed requirements to meet CAA sections

112(f)(2) and (d)(6) for storage vessels?

C. What are the proposed requirements to meet CAA sections

112 (f)(2) and (d)(6) for EBU used to treat Group 1

wastewater streams?

D. What are the proposed requirements for cooling towers under

CAA sections 112(d)(2) and (f)(2)?

E. What other revisions are we proposing?

F. What is the compliance schedule for the proposed amendments?

IV\. Rationale for Proposed Amendments

A. What actions are we proposing under CAA section 112(d)(2)?

B. How did we estimate residual risk?

C. What are the residual risks from petroleum refineries?

D. What are the uncertainties in risk assessments?

E. What is our proposed decision under CAA section 112(f)?

F. What is EPA proposing pursuant to CAA section 112(d)(6)?

V. Request for Comments

VI\. Statutory and Executive Order Reviews

A. Executive Order 12866: Regulatory Planning and Review

B. Paperwork Reduction Act

C. Regulatory Flexibility Act

D. Unfunded Mandates Reform Act

E. Executive Order 13132: Federalism

F. Executive Order 13175: Consultation and Coordination with

Indian Tribal Governments

G. Executive Order 13045: Protection of Children from

Environmental Health Risks and Safety Risks

H. Executive Order 13211: Actions Concerning Regulations That

Significantly Affect Energy Supply, Distribution, or Use

I. National Technology Transfer and Advancement Act

J. Executive Order 12898: Federal Actions to Address

Environmental Justice in Minority Populations and Low-Income

Populations

**II. Background Information**

A. [What is the statutory authority for regulating hazardous air
pollutants]{.underline}?

Section 112 of the Clean Air Act (CAA) establishes a two-stage
regulatory process to address emissions of hazardous air pollutants
(HAP) from stationary sources. In the first stage, after EPA has
identified categories of sources emitting one or more of the HAP listed
in section 112(b) of the CAA, section 112(d) calls for us to promulgate
national emission standards for hazardous air pollutants (NESHAP) for
those sources. For "major sources" that emit or have the potential to
emit any single HAP at a rate of 10 tons or more per year or any
combination of HAP at a rate of 25 tons or more per year, these
technology-based standards must reflect the maximum reductions of HAP
achievable (after considering cost, energy requirements, and non-air
quality health and environmental impacts) and are commonly referred to
as maximum achievable control technology (MACT) standards.

The MACT floor is the minimum control level allowed for NESHAP and is
defined under section 112(d)(3) of the CAA. For new sources, the MACT
floor cannot be less stringent than the emission control that is
achieved in practice by the best-controlled similar source. The MACT
standards for existing sources can be less stringent than standards for
new sources, but they cannot be less stringent than the average emission
limitation achieved by the best-performing 12 percent of existing
sources in the category or subcategory (or the best-performing
five sources for categories or subcategories with fewer than
30 sources). In developing MACT, we must also consider control options
that are more stringent than the floor. We may establish standards more
stringent than the floor based on the consideration of the cost of
achieving the emissions reductions, any non-air quality health and
environmental impacts, and energy requirements. We published the final
MACT standards for petroleum refineries (40 CFR part 63, subpart CC) on
August 18, 1995 (60 FR 43620).

The EPA is then required to review these technology-based standards and
to revise them "as necessary (taking into account developments in
practices, processes, and control technologies)" no less frequently than
every 8 years, under CAA section 112(d)(6). In this proposal, we are
publishing the results of our 8-year review for the petroleum refineries
source category. We are required by a consent decree to propose the
results of our CAA section 112(d)(6) review by August 21, 2007. The
consent decree also requires EPA to consider and address the application
of the NESHAP general provisions in 40 CFR part 63, subpart A to the
existing rule.

The second stage in standard-setting focuses on reducing any remaining
"residual" risk according to CAA section 112(f). This provision
requires, first, that EPA prepare a Report to Congress discussing (among
other things) methods of calculating risk posed (or potentially posed)
by sources after implementation of the MACT standards, the public health
significance of those risks, the means and costs of controlling them,
actual health effects to persons in proximity of emitting sources, and
recommendations as to legislation regarding such remaining risk. EPA
prepared and submitted this report (Residual Risk Report to Congress,
EPA--453/R--99--001) in March 1999. Congress did not act in response to
the report, thereby triggering EPA's obligation under CAA section
112(f)(2) to analyze and address residual risk.

CAA Section 112(f)(2) requires us to determine for source categories
subject to certain section 112(d) standards whether the emissions
limitations protect public health with an ample margin of safety. If the
MACT standards for HAP "classified as a known, probable, or possible
human carcinogen do not reduce lifetime excess cancer risks to the
individual most exposed to emissions from a source in the category or
subcategory to less than 1-in-1 million," EPA must promulgate residual
risk standards for the source category (or subcategory) as necessary to
provide an ample margin of safety to protect public health. The EPA must
also adopt more stringent standards if necessary to prevent an adverse
environmental effect (defined in CAA section 112(a)(7) as any
significant and widespread adverse effect \* \* \* to wildlife, aquatic
life, or natural resources \* \* \*), but must consider cost, energy,
safety, and other relevant factors in doing so. Section 112(f)(2) of the
CAA expressly preserves our use of a two-step process for developing
standards to address any residual risk and our interpretation of "ample
margin of safety" developed in the National Emission Standards for
Hazardous Air Pollutants: Benzene Emissions from Maleic Anhydride
Plants, Ethylbenzene/Styrene Plants, Benzene Storage Vessels, Benzene
Equipment Leaks, and Coke By-Product Recovery Plants (Benzene NESHAP)
(54 FR 38044, September 14, 1989).

The first step in this process is the determination of acceptable risk.
The second step provides for an ample margin of safety to protect public
health, which is the level at which the standards are set (unless a more
stringent standard is required to prevent an adverse environmental
effect after the consideration of costs, energy, safety, and other
relevant factors).

The terms "individual most exposed," "acceptable level," and "ample
margin of safety" are not specifically defined in the CAA. However, CAA
section 112(f)(2)(B) directs us to use the interpretation set out in the
Benzene NESHAP. See also, A Legislative History of the Clean Air Act
Amendments of 1990, volume 1, p. 877 (Senate debate on Conference
Report). We notified Congress in the Residual Risk Report to Congress
that we intended to use the Benzene NESHAP approach in making CAA
section 112(f) residual risk determinations (EPA-453/R-99-001, p.
ES-11).

In the Benzene NESHAP, we stated as an overall objective:

> . . . in protecting public health with an ample margin of safety, we
> strive to provide maximum feasible protection against risks to health
> from hazardous air pollutants by (1) protecting the greatest number of
> persons possible to an individual lifetime risk level no higher than
> approximately 1-in-1 million; and (2) limiting to no higher than
> approximately 1-in-10 thousand \[i.e., 100-in-1 million\] the
> estimated risk that a person living near a facility would have if he
> or she were exposed to the maximum pollutant concentrations for 70
> years.

The Agency also stated that, "The EPA also considers incidence (the
number of persons estimated to suffer cancer or other serious health
effects as a result of exposure to a pollutant) to be an important
measure of the health risk to the exposed population. Incidence measures
the extent of health risk to the exposed population as a whole, by
providing an estimate of the occurrence of cancer or other serious
health effects in the exposed population." The Agency went on to
conclude that "estimated incidence would be weighed along with other
health

risk information in judging acceptability."[^1] As explained more fully
in our Residual Risk Report to Congress, EPA does not define "rigid
line\[s\] of acceptability," but considers rather broad objectives to be
weighed with a series of other health measures and factors
(EPA-453/R-99-001, p. ES-11).

The determination of what represents an "acceptable" risk is based on a
judgment of "what risks are acceptable in the world in which we live"
(54 FR 38045, quoting the [Vinyl Chloride]{.underline} decision at 824
F.2d 1165) recognizing that our world is not risk-free.

In the Benzene NESHAP, we stated that "EPA will generally presume that
if the risk to \[the maximum exposed\] individual is no higher than
approximately 1-in-10 thousand, that risk level is considered
acceptable." We discussed the maximum individual lifetime cancer risk as
being "the estimated risk that a person living near a plant would have
if he or she were exposed to the maximum pollutant concentrations for 70
years." We explained that this measure of risk "is an estimate of the
upper bound of risk based on conservative assumptions, such as
continuous exposure for 24 hours per day for 70 years." We acknowledge
that maximum individual lifetime cancer risk "does not necessarily
reflect the true risk, but displays a conservative risk level which is
an upper bound that is unlikely to be exceeded."

Understanding that there are both benefits and limitations to using
maximum individual lifetime cancer risk as a metric for determining
acceptability, we acknowledged in the 1989 Benzene NESHAP that
"consideration of maximum individual risk . . . must take into account
the strengths and weaknesses of this measure of risk." Consequently, the
presumptive risk level of 100-in-1 million (1-in-10 thousand) provides a
benchmark for judging the acceptability of maximum individual lifetime
cancer risk, but does not constitute a rigid line for making that
determination.

-   

-   

-   

-   The Agency also explained in the 1989 Benzene NESHAP the following:
    "In establishing a presumption for MIR, rather than rigid line for
    acceptability, the Agency intends to weigh it with a series of other
    health measures and factors. These include the overall incidence of
    cancer or other serious health effects within the exposed
    population, the numbers of persons exposed within each individual
    lifetime risk range and associated incidence within, typically, a 50
    km exposure radius around facilities, the science policy assumptions
    and estimation uncertainties associated with the risk measures,
    weight of the scientific evidence for human health effects, other
    quantified or unquantified health effects, effects due to
    co-location of facilities, and co-emission of pollutants."

-   

-   In some cases, these health measures and factors taken together may
    provide a more realistic description of the magnitude of risk in the
    exposed population than that provided by maximum individual lifetime
    cancer risk alone.

    B. [What source category is affected by this action]{.underline}?

Petroleum refineries are facilities engaged in refining and producing
products made from crude oil or unfinished petroleum derivatives. Based
on the Energy Information Administration's Refinery Capacity Report
2006, there are 150 operable petroleum refineries in the United States
(U.S.) and the U.S. territories. A few of these 150 refineries have
integrated operations between two nearby, but non-contiguous, locations.
Therefore, we have identified and have data on 153 distinct petroleum
refinery facilities (according to the definition of facility in the
CAA), all of which are major sources of HAP emissions. Petroleum
refineries are located in 35 States, as well as Puerto Rico and the U.S.
Virgin Islands. Texas, Louisiana, and California are the States with the
most petroleum refining capacity. The permitting process has begun for
construction of a new refinery in Arizona; this is the only newly
constructed refinery anticipated over the next 5 years. However, a few
additional refineries have announced significant expansion or
modification projects that will essentially double their refining
capacity.

EPA listed two separate Petroleum Refinery source categories for
regulation under CAA section 112(d), both of which include any facility
engaged in producing gasoline, naphtha, kerosene, jet fuels, distillate
fuel oils, residual fuel oils, lubricants, or other products from crude
oil or unfinished petroleum derivatives. The first and primary source
category for which regulations were developed, Petroleum Refineries -
Other Sources Not Distinctly Listed (Refinery MACT 1), includes all
emission sources from petroleum refinery process units except those that
were expected to be regulated elsewhere, such as the NESHAP for Boilers
and Process Heaters (40 CFR part 63 subpart DDDDD). Refinery process
units include, but are not limited to: crude distillation, vacuum
distillation, thermal cracking, catalytic cracking, catalytic reforming,
hydrotreating, hydrorefining, isomerization, polymerization, lube oil
processing, and hydrogen production. The Refinery MACT 1 rule
specifically excludes three types of process vents: catalytic cracking
unit catalyst regeneration vents, catalytic reforming unit catalyst
regeneration vents, and sulfur plant vents. These specific vents are
regulated by the NESHAP for Petroleum Refineries: Catalytic Cracking
Units, Catalytic Reforming Units, and Sulfur Recovery Units (Refinery
MACT 2) in 40 CFR part 63, subpart UUU. It is important to note that
equipment leaks and wastewater produced from catalytic cracking units,
catalytic reforming units, and sulfur recovery units are subject to
Refinery MACT 1; only the process vent emissions associated with these
units are subject to Refinery MACT 2.

C. [What are the emissions sources at petroleum refineries]{.underline}?

The emissions sources subject to the Refinery MACT 1 rule include
miscellaneous process vents, storage vessels, wastewater streams, and
equipment leaks associated with petroleum refining process units, as
well as gasoline loading racks and marine tank vessel loading operations
located at a petroleum refinery. Storage vessels and equipment leaks
associated with a bulk gasoline terminal or pipeline breakout station
located at a petroleum refinery and under common control of the refinery
are also subject to Refinery MACT 1. Cooling towers associated with
petroleum refining process units are part of the MACT 1 source category
although no specific emission limitations were established for cooling
towers in the original Refinery MACT 1 rule. Thus, there are seven
general types of emission sources under Refinery MACT 1: miscellaneous
process vents, storage vessels, wastewater streams, equipment leaks,
gasoline loading racks, marine tank vessel loading operations, and
cooling towers. Each of these emission sources are described briefly in
sections II.C.1 through II.C.7 of this preamble.

1\. Miscellaneous Process Vents

Many unit operations at petroleum refineries generate gaseous streams
that contain HAP. These streams may be routed to other unit operations
for additional processing (i.e., a gas stream from a reactor that is
routed to a distillation unit for separation) or they may be sent to a
blowdown system or vented to the atmosphere. Miscellaneous process vents
emit gases to the atmosphere, either directly or after passing through
recovery and/or control devices.

2\. Storage Vessels

Storage vessels contain crude oil, intermediate products, and finished
products. Different types of vessels are used to store various types of
products. Gases are stored in pressurized vessels that are not vented to
the atmosphere during normal operations while liquids are stored in
horizontal, fixed roof, or floating roof tanks, depending on properties
and volumes to be stored. Liquids with vapor pressures greater than 11
pounds per square inch of air (psia) are typically stored in fixed roof
tanks that are vented to a control device. Volatile liquids with vapor
pressures up to 11 psia are usually stored in floating roof tanks
because such vessels have lower emission rates than fixed roof tanks
within this vapor pressure range. Emissions from storage vessels
typically occur as working losses. As a storage vessel is filled,
HAP-laden vapors inside the tank become displaced and can be emitted to
the atmosphere. Also, diurnal temperature changes result in breathing
losses of organic HAP-laden vapors from storage vessels.

3\. Wastewater Streams

Many refinery process units generate wastewater streams that contain
HAP. Significant wastewater sources include the crude desalting unit,
process waters, steam stripper blowdown, and storage tank draws. Organic
HAP compounds in the wastewater can volatilize and be emitted to the
atmosphere from wastewater collection and treatment units if these units
are open or vented to the atmosphere. Potential sources of HAP emissions
associated with wastewater collection and treatment systems include
drains, manholes, trenches, surface impoundments, oil/water separators,
storage and treatment tanks, junction boxes, sumps, basins, and
biological treatment systems.

4\. Equipment Leaks

Equipment leaks are releases of process fluid or vapor from processing
equipment, including pump and compressor seals, process valves, pressure
relief devices, open-ended lines, flanges and other connectors,
agitators, and instrumentation systems. These releases occur primarily
at the interface between connected components of equipment or in sealing
mechanisms.

5\. Gasoline Loading Racks

Loading racks are the collection of equipment, including loading arms,
pumps, meters, shutoff valves, relief valves, and other piping and
valves used to fill gasoline cargo tanks. Emissions from loading racks
may be released when gasoline loaded into cargo tanks displaces vapors
inside these containers.

6\. Marine Vessel Loading Operations

Marine vessel loading operations load and unload liquid commodities in
bulk, such as crude oil, gasoline and other fuels, and naphtha. The
cargo is pumped from the terminal\'s large, above-ground storage tanks
through a network of pipes and into a storage compartment (tank) on the
vessel. The HAP emission result from the displaced vapors during the
filling operation.

7\. Cooling Towers

Cooling tower systems include closed loop recirculation systems and once
through systems that receive non-contact process water from a heat
exchanger for the purposes of cooling the process water prior to
returning the water to the heat exchanger or discharging the water to
another process unit, waste management unit, or to a receiving water
body. Cooling towers typically use force draft air ventilation of the
process water to cool the process water. Heat exchangers occasionally
develop leaks which result in process fluids entering the cooling tower
process water. The HAP and other organics in these process fluids are
then emitted to the atmosphere due to stripping in the cooling tower.
Cooling tower emissions arising from the addition of chemicals to the
cooling water to prevent fouling or to decontaminate the water are not
covered by this standard, but are instead covered under the Industrial
Process Cooling Tower NESHAP.

D. [What hazardous air pollutants are emitted from petroleum
refineries]{.underline}?

The specific HAP emitted by petroleum refineries varies by facility and
process operations but can include a variety of organic and inorganic
compounds and metals. Emissions originate from various process vents,
storage vessels, wastewater streams, loading racks, marine tank vessel
loading operations, and equipment leaks associated with refining
facilities. Process vents, wastewater streams, and storage vessels
generally emit organic HAP. Organic compounds account for the majority
of the total mass of HAP emitted by petroleum refinery sources, with
toluene, hexane, mixed and individual isomers of xylenes, benzene,
methanol, methyl tert-butyl ether, and ethyl benzene accounting for
about 90 percent of the HAP mass emitted. Other HAP emissions may
include biphenyl, 1,3-butadiene, cumene, carbon disulfide, carbonyl
sulfide, cresols, ethylene dibromide, 1,2 dichloroethane,
diethanolamine, ethylene glycol, methyl isobutyl ketone,
2,2,4-trimethylpentane, naphthalene, and phenol.

The

HAP emitted from emissions sources subject to the Refinery MACT 1 rule
are associated with a variety of health effects, depending on the
specific pollutants involved and the degree and duration of exposure.
The range of adverse health effects include cancer and a number of other
chronic health disorders (e.g., aplastic anemia, panctopenia, pernicious
anemia, lung structural changes) and a number of acute health disorders
(difficulty in breathing, upper respiratory tract irritation,
conjunctivitis, tremors, delirium, coma, convulsions). More details on
the health effects of individual HAP may be found in numerous sources,
including [www.epa.gov/iris.html](http://www.epa.gov/iris.html),
[www.atsdr.cdc.govlmrls.html](http://www.atsdr.cdc.govlmrls.html/), and
[www.oehha.ca.gov/air/acute_rels/index.html](http://www.oehha.ca.gov/air/acute_rels/index.html).

E. [What does the NESHAP require]{.underline}?

The Refinery MACT 1 rule (40 CFR part 63, subpart CC) applies to
petroleum refining process units and their collocated emissions points
that are part of a plant site that is a major source and that emit or
have equipment containing or contacting one or more of the 28 HAP listed
in Table 1 in the appendix to the rule. Section 63.640(c) of the rule
specifies that emissions points subject to the rule include an
individual miscellaneous process vent, storage vessel, wastewater
stream, or equipment leak associated with a petroleum refining process
unit; an individual storage vessel or equipment leak associated with a
bulk gasoline terminal or pipeline breakout station classified under
Standard Industrial Classification (SIC) code 2911 located at a
petroleum refinery; a gasoline loading rack classified under SIC code
2911 located at a petroleum refinery and under common control with the
refinery; or a marine tank vessel loading operation located at a
petroleum refinery. The rule establishes applicability criteria to
distinguish between Group 1 emissions points and Group 2 emissions
points. Controls are required only for emissions points meeting the
Group 1 criteria. Group 2 emissions points are subject to recordkeeping
requirements only. We estimate that the 1995 rule reduces HAP emissions
by 53,000 tons per year (tpy) -- a 59 percent reduction (60 FR 43248,
August 18, 1995).

Section 63.641 of the rule defines Group 1 miscellaneous process vents
as those with volatile organic compound (VOC) emissions equal to or
greater than 33 kilograms per day (kg/day) (72 pounds per day (lb/day))
for existing sources and 6.8 kg/day (15 lb/day) for new sources. Under
§63.643, the owner or operator of a Group 1 miscellaneous process vent
must reduce organic HAP using a flare that meets the equipment
specifications in 40 CFR 63.11 of the general provisions (subpart A) or
use a control device to reduce organic HAP emissions by 98
weight-percent or to a concentration of 20 parts per million by volume
(ppmv dry basis, corrected to 3 percent oxygen).

Section 63.646(a) of the Refinery MACT 1 rule requires each Group 1
storage vessel to comply with 40 CFR 63.119 through 63.121 of subpart G
(National Emission Standards for Organic Hazardous Air Pollutants From
the Synthetic Organic Chemical Manufacturing Industry for Process Vents,
Storage Vessels, Transfer Operations, and Wastewater). A Group 1 storage
vessel at an existing refinery has a design storage capacity and maximum
true vapor pressure greater than the values specified in the existing
rule. Under 40 CFR 63.119, a Group 1 storage vessel must be equipped
with an internal floating roof with proper seals, an external floating
roof with proper seals, an external floating roof converted to an
internal floating roof with proper seals, or a closed vent system to a
control device that reduces HAP emissions by 95 percent or to 20 ppmv.
Storage vessels at existing sources are not subject to certain equipment
specifications and inspection requirements for automatic bleeder vents,
gaskets, slotted membranes, and sleeve seals. See 40 CFR 63.640(c). The
requirements for a Group 1 storage vessel at a new refinery apply to
tanks with a smaller design capacity and lower vapor pressures and HAP
liquid concentration. These tanks also must comply with the storage
vessel requirements in 40 CFR part 63, subpart G.

Each Group 1 wastewater stream at a new or existing refinery must comply
with 40 CFR 61.340 through 61.355 of the National Emission Standard for
Benzene Waste Operations (BWON) in 40 CFR part 61, subpart FF. Group 1
wastewater streams are those wastewater streams (at a petroleum refinery
that has a total annual benzene loading of 10 megagrams per year (Mg/yr)
or greater) that have a flow rate greater than 0.02 liters per minute, a
benzene concentration of 10 parts per million by weight (ppmw) or
greater, and are not exempt from control requirements under the BWON.
The BWON requires affected waste streams to comply with one of several
options for controlling benzene emissions from waste management units
and treating the benzene containing wastes.

The Refinery MACT 1 rule requires the owner or operator of an existing
refinery to comply with the equipment leak provisions in 40 CFR part 60,
subpart VV (Standards of Performance for Equipment Leaks of VOC in the
Synthetic Organic Chemicals Manufacturing Industry) for all equipment in
organic HAP service. The term "in organic HAP service" means that a
piece of equipment either contains or contacts a fluid (liquid or gas)
that is at least 5 percent by weight of total organic HAP. The owner or
operator of a new facility must comply with a modified version of 40 CFR
part 63, subpart H (National Emission Standards for Organic Hazardous
Air Pollutants for Equipment Leaks). Both subpart VV of part 60 and
modified subpart H of part 63 require inspection and repair of leaking
equipment. The leak definition under subpart VV that triggers repair
requirements is an instrument reading of 10,000 ppmv. In the modified
version of subpart H, the leak definition for pumps and valves begins at
10,000 ppmv but drops to 2,000 ppmv or 1,000 ppmv, respectively, in
subsequent years.

Group 1 gasoline loading racks at refineries must comply with the
requirements of the National Emission Standards for Gasoline
Distribution Facilities (Bulk Gasoline Terminals and Pipeline Breakout
Stations) in 40 CFR part 63, subpart R. Marine tank vessel loading
operations at refineries must comply with the requirements in 40 CFR
part 63, subpart Y (National Emission Standards for Marine Tank Vessel
Loading Operations).

**III. Summary of Proposed Amendments to NESHAP for Petroleum
Refineries**

A. [What options are we proposing]{.underline}?

We are proposing regulatory options for storage vessels with external
floating roofs and regulatory options for an enhanced biodegradation
unit (EBU) to meet the requirements of CAA sections 112(f)(2) and
(d)(6). We are also proposing options to require a leak detection and
repair program for cooling towers under section 112(d)(2) and (f)(2).

A detailed summary of the proposed amendments under the requirements of
CAA section 112(f)(2) and (d)(6) is provided below. This section also
includes our discussion of the proposal to regulate cooling towers under
CAA section 112(d)(2) and (f)(2). Our rationale for the proposed
amendments is provided in section IV of this preamble.

B. [What are the proposed requirements to meet CAA sections 112(f)(2)
and (d)(6) for storage vessels]{.underline}?

Currently, the Refinery MACT 1 rule requires Group 1 storage vessels at
an existing source to comply with the requirements in 40 CFR 63.119
through 63.121 of 40 CFR part 63, subpart G, except where specifically
noted. Under 40 CFR 63.640(c) of the rule, storage vessels at existing
sources are not subject to the requirements in 40 CFR 63.119(b)(5),
(b)(6), (c)(2), and (d)(2) of subpart G. The requirements in 40 CFR
63.119(c)(2) contain equipment specifications for storage tanks with
external floating roofs.

EPA is proposing two regulatory options for storage vessels. We believe
that either of these options might achieve an ample margin of safety as
described in the Benzene NESHAP. The Agency's basis for selecting one of
these options in the final rule would reflect our consideration of the
relative risk reduction and cost of the options, as well as
consideration of other relevant factors as identified in the Benzene
NESHAP. For existing storage vessels, Option 1 requires no revisions to
the Refinery MACT 1 rule to meet the requirements of CAA section
112(d)(6) and (f)(2). Option 2 would remove the current exemption for
the requirements in 40 CFR 63.119(c)(2)(ix) and (x) for slotted guide
poles. Removal of this exemption would require the owner or operator of
a Group 1 storage vessel at an existing source that is equipped with an
external floating roof to equip each slotted guide pole with a gasketed
sliding cover or flexible fabric sleeve seal and a gasketed cover or
other device which closes off the liquid surface from the atmosphere.
The proposed amendments also revise related inspection requirements in
40 CFR 63.646(e) and reporting requirements in 40 CFR
63.654(f)(1)(A)[(1)]{.underline}, (g)(1), and (g)(3)(iii)(A) to account
for the requirements for slotted guide poles.

C. [What are the proposed requirements to meet CAA sections 112(f)(2)
and (d)(6) for EBU used to treat Group 1 wastewater
streams]{.underline}?

EPA is proposing two regulatory options for EBU. We believe that either
of these options might achieve an ample margin of safety as described in
the Benzene NESHAP. The Agency's basis for selecting one of these
options in the final rule would reflect our consideration of the
relative risk reduction and cost of the options, as well as
consideration of other relevant factors as identified in the Benzene
NESHAP.

Option 1 requires no revisions to the Refinery MACT 1 rule to meet the
requirements of CAA sections 112(f)(2) and (d)(6). Option 2 for EBU
proposes to revise the wastewater provisions in the Refinery MACT 1 rule
to add a specific performance standard and monitoring requirement for
EBU. The proposed amendments require owners or operators to operate and
maintain EBU to achieve a minimum treatment efficiency for benzene of 90
percent. The owner or operator would be required to conduct an initial
performance demonstration using the procedures in 40 CFR part 63,
appendix C (Determination of the Fraction Biodegraded (F~bio~) in a
Biological Treatment Unit). Based on the demonstration results,
facilities would establish operating limits for the mixed liquor
volatile suspended solids (MLVSS) concentration and the
food-to-microorganism ratio according to the rule requirements. The
operating parameters would be monitored at least once a week. Exceedance
of an operating limit would be a deviation that must be reported in the
periodic (semiannual) report required by 40 CFR 63.654.

D. [What are the proposed requirements for cooling towers under CAA
sections 112(d)(2) and (f)(2)]{.underline}?

Because the Refinery MACT 1 rule does not address HAP emissions from
cooling towers, we are proposing to regulate cooling towers under CAA
section 112(d)(2) and (d)(3) in this action. As we are proposing later
in the preamble, once cooling towers have been regulated pursuant to CAA
section (d)(2) and (d)(3), no additional controls are needed to provide
an adequate margin of safety under CAA section (f)(2).

We are proposing work practice standards for cooling towers which would
require the owner or operator of a new or existing source to monitor for
leaks in the cooling tower return lines from heat exchangers in organic
HAP service (i.e., lines that contain or contact fluids with 5 weight
percent or greater of total organic HAP listed in Table 1 of the rule)
and, where leaks are detected, to repair such leaks within a specified
period of time. The two options that are being co-proposed differ in the
detection methods used to identify leaks for existing sources, and in
the frequency of monitoring for new sources. The first option reflects
our MACT floor analysis and would reject imposing controls beyond the
MACT floor. Under this option, the owner or operator of existing source
cooling towers receiving cooling water from heat exchangers in organic
HAP service would be required to monitor chemical addition rates or
other surrogate indicators of leaks. If the surrogate indicators suggest
a leak, the owner or operator would conduct sampling and analyses to
determine if the indicated leak is an organic HAP leak. For existing
sources, an organic HAP leak is defined as an organic HAP concentration
in the cooling tower water of 1 ppmw or greater. Owner and operators of
new source cooling towers receiving cooling water from heat exchangers
in organic HAP service would be required to conduct quarterly sampling
and analyses to identify any organic HAP leaks into the cooling tower
water and to take appropriate corrective action to fix the leaks.

Under the second option, we would select a control option based on our
beyond the floor analysis and would require the owner or operator of new
and existing sources to conduct monthly sampling and analyses to
identify any organic HAP leaks into the cooling tower water.

Under both options, a leak into the cooling tower water would be defined
as either a mass leak rate of 100 pounds of total organic HAP per day or
greater or a mass leak rate of 10 pounds of any single organic HAP per
day or greater. Under both options, if a leak is detected, the owner or
operator would be required to identify the source of the leak as soon as
practicable but not later than 30 days after receiving the sampling
results. Unless a delay in repair is allowed under the proposed
requirements, the owner or operator would be required to repair the leak
no later than 30 days after identifying the source of the leak. The
proposed rule would allow a delay in repair of the leak if repair of the
leak would require the process unit served by the leaking heat exchanger
to be shut down, and the shutdown would result in greater emissions than
the potential emissions from the cooling tower leak from the time the
leaking heat exchanger was first identified and the next planned
shutdown. The owner or operator would be required to continue monthly
monitoring and repair the heat exchanger within 30 days if sampling
results show that the projected emissions from the cooling tower exceed
the startup and shutdown emissions estimates. The proposed rule would
also allow a delay in repair if the necessary parts are not reasonably
available. In this case, the owner or operator would be required to
complete the repair as soon as practicable upon receiving the necessary
parts, but no later than 120 days after identifying the leaking heat
exchanger. All new or existing refineries with a cooling tower system
also would be required to prepare and follow a monitoring plan for
cooling towers. The plan is necessary to document emissions potential
for employing the delay of repair provisions.

E. [What other revisions are we proposing]{.underline}?

We are also proposing clarifications to the requirements in the Refinery
MACT 1 rule. The proposed amendments clarify that the control
requirements for gasoline loading racks apply to Group 1 gasoline
loading racks. "Group 1 gasoline loading rack" is the term used to
define the affected emissions source subject to emissions control
requirements. This clarification would amend 40 CFR 63.640 of subpart
CC.

F. [What is the compliance schedule for the proposed
amendments]{.underline}?

The proposed amendments to the Refinery MACT 1 rule would become
effective on the date of publication of the final amendments in the
**Federal Register**. Under section 112 (i)(1) of the CAA, any new
facility would be required to comply upon startup. For existing sources,
CAA section 112(i)(3)(A) requires compliance no later than 3 years after
the effective date of the standard. The proposed 3-year compliance date
is appropriate because it will allow facilities time to perform
monitoring and install required controls. For cooling towers, we are
allowing 3 years to identify which towers are affected, to identify the
ability to repair these cooling towers without a process unit
turnaround, to determine the HAP emissions that would occur if a
shutdown is required to control a heat exchanger leak, and to establish
an appropriate monitoring program that meets the requirements of the
proposed rule. For EBU, 3 years is necessary to perform tests of benzene
destruction efficiency, to calculate the overall effectiveness of the
EBU using the procedures in Appendix C, to establish appropriate
monitoring provisions and install and test necessary equipment, and to
make modifications to the EBU if necessary to increase the efficiency of
the system to meet the proposed requirements. For storage tanks, 3 years
are being proposed to allow flexibility in the addition of the guidepole
controls for safety and operational concerns. In promulgating similar
requirements for storage tanks, we have extended the compliance time
until the next scheduled turnaround requiring emptying and degassing of
the tank or 10 years, whichever is sooner. This is because the emissions
that occur during emptying and degassing exceed the HAP emission
reductions that would occur as a result of applying the controls. We are
requesting comments on whether it is necessary to empty and degas tanks
for retrofitting the proposed controls.

**IV. Rationale for Proposed Amendments**

A. [What actions are we proposing]{.underline} [under CAA section
112(d)(2)?]{.underline}

We did not establish standards for cooling towers in the Refinery MACT 1
rule. Industry emissions information and data demonstrate that organic
HAP emissions from cooling towers at petroleum refineries are
significant, and we are proposing to add emissions standards for organic
HAP from cooling towers at petroleum refineries under the authority of
CAA section 112(d)(2). Because the emissions from cooling towers are not
emitted through a stack and are not practically measurable, we have
established work practice standards as provided for under CAA section
112(h)(2) to address these emissions.

In evaluating the MACT floor, we must determine the average emissions
limitations achieved by the top 12 percent of the affected sources. We
have often interpreted the average of the top 12 percent as the
performance of the 6th percentile unit. Of the 150 refineries, the 6th
percentile is represented by the 9th ranked top-performing unit. Based
on available information, we have determined that the top 12 percent of
the industry currently implements cooling tower monitoring programs to
detect and repair leaks of process fluids into cooling water using
chemical usage rates or other surrogate indicators of heat exchanger
leaks. Therefore, we have determined that the MACT floor for existing
cooling towers is monitoring of surrogate indicators of heat exchanger
leaks in cooling water and to repair leaks. The nationwide total annual
cost (TAC) to conduct cooling tower monitoring of surrogate indicators
and repairs is estimated to be \$750,000. This cost includes a product
recovery credit of \$1.2 million, and includes no costs for repair of
heat exchangers under that assumption that refiners would repair leaking
heat exchangers when they are made aware of the leak as part of their
routine operations. For large leaks, reasons for repairing leaks
immediately could be safety concerns or the recovery of large product
losses. For smaller leaks, these concerns might not be valid and
therefore refiners might incur additional costs beyond routine
operations. EPA requests comment on the extent to which immediate
repairs would be based on these concerns, and on typical costs of
repair. The HAP emissions reduction for the MACT floor is estimated to
be 373 tpy total HAP and 28.3 tpy of benzene. The HAP baseline for
cooling towers was estimated to be 3,024 tpy.

The MACT floor for new sources is represented by the best-performing
similar unit. Based on all of the information available, the best
performance standard currently being implemented is direct organic
chemical concentration monitoring of their Refinery MACT 1 cooling
towers on a quarterly basis. Based on emissions data for the facility
implementing this program, we have determined that the performance of
this cooling tower monitoring program would limit leaks into the cooling
water to less than 10 lbs/day of a single organic HAP and less than 100
lbs/day of total organic HAP. Therefore, we have determined that the
MACT floor for new cooling towers is quarterly organic chemical-specific
monitoring with an action level of 10 lbs/day or greater of a single
organic HAP and 100 lbs/day or greater of total organic HAP.

EPA has concluded, based on available data, that existing industry
monitoring of surrogate parameters will only detect large leaks, which
would miss leaks that would generate significant organic HAP emissions
(see memorandum to docket: Cooling towers: Control Options and Impact
Estimates). EPA analyzed the amount of HAP that could be emitted from
cooling water based on HAP concentration data and flow rates for cooling
towers at several petroleum refinery facilities and decided to structure
regulatory options to account for variable cooling water flow and
minimum detection limit capabilities of 10 parts per billion by weight
(ppbw) for the concentrations of individual HAP in water. For example,
at a petroleum refinery with total organic HAP concentration of 30 ppbw
and a cooling water flow rate of 40,000 gallons per minute (gal/min),
the potential organic HAP emissions from the cooling tower are 14
lbs/day or over 2.5 tons if the leak lasted for a year.

As part of our beyond the floor analysis, we considered alternatives
more stringent than the MACT floor option for existing and new sources.
For existing and new sources, we identified two alternatives that would
require monitoring by collecting a cooling water sample and analyzing
for speciated HAP. In both alternatives, the cost of the monitoring is
likely less than the value of the product that would no longer be lost
to the atmosphere. Additionally, we have not included repair costs in
any of the options as we considered these costs to be routine
operational costs. The costs discussed also apply to new as well as
existing sources, since there are no retrofit issues associated with the
proposed monitoring program.

One alternative more stringent than the MACT floor includes
[quarterly]{.underline} monitoring of cooling water by water sampling
and a leak definition of greater than or equal to 10 pounds of any
single organic HAP or greater than or equal to 100 pounds organic HAP
per day and results in a total annualized cost saving of \$2.1 million.
This savings includes a product recovery credit of \$4.4 million. The
organic HAP emissions reduction for this alternative regulatory option 1
is 1,330 tpy and the cost-effectiveness is -\$1,600/ton.

Another alternative more stringent than the MACT floor includes
[monthly]{.underline} monitoring of cooling water by water sampling and
a leak definition of greater than or equal to 10 pounds of any single
organic HAP or greater than or equal to 100 pounds organic HAP per day.
The nationwide TAC is a savings of \$1.6 million, including a recovery
credit of \$5.7 million. The organic HAP emissions reduction for this
alternative is 1,720 tpy. The cost-effectiveness of this alternative is
-\$920/ton.

EPA is co-proposing two options for finalizing MACT standards for new
and existing cooling towers. Option 1 represents the MACT floor for new
and existing units, as discussed above. Option 2 is more stringent than
the MACT floor and is described above as requiring monthly (as opposed
to quarterly) monitoring of individual (speciated) organic HAP. Table 1
of this preamble summarizes nationwide impacts of the proposed options.

Table 1. Nationwide Impacts for Cooling Tower Options

+-------+---------+----------+----------+----------+-------+----------+
| O     | Mon     | Product  | Total    | HAP      | Cos   |          |
| ption | itoring | Recovery | Annual   | E        | t-Eff |          |
|       | Cost    | Credit   | Cost     | missions | ectiv |          |
|       | (\      |          | (\$1     | (tons/yr | eness |          |
|       | $1,000) | (\$1     | ,000/yr) | HAP)     | (\$   |          |
|       |         | ,000/yr) |          |          | /ton) |          |
+-------+---------+----------+----------+----------+-------+----------+
|       |         |          |          |          | Ov    | Inc      |
|       |         |          |          |          | erall | remental |
+-------+---------+----------+----------+----------+-------+----------+
| Bas   | 0       | 0        | 0        | 3,024    | 0     | 0        |
| eline |         |          |          |          |       |          |
+-------+---------+----------+----------+----------+-------+----------+
| 1     | 1,990   | -1,240   | 750      | 2,647    | 1,980 | 1,980    |
|       |         |          |          |          |       |          |
| (MACT |         |          |          |          |       |          |
| F     |         |          |          |          |       |          |
| loor) |         |          |          |          |       |          |
+-------+---------+----------+----------+----------+-------+----------+
| 2     | 4,100   | -5,680   | -1,590   | 1,304    | -920  | -1,750   |
|       |         |          |          |          |       |          |
| (B    |         |          |          |          |       |          |
| eyond |         |          |          |          |       |          |
| the   |         |          |          |          |       |          |
| f     |         |          |          |          |       |          |
| loor) |         |          |          |          |       |          |
+-------+---------+----------+----------+----------+-------+----------+

Note: the monthly monitoring alternative is projected to result in a
positive incremental cost-effectiveness of \$1,400 per ton (as compared
to the quarterly alternative).

  ------- ---------- ------------ ----------- --------- --------------------
                                                        

                                                        

                                                        

                                                        

                                                        XXXX
  ------- ---------- ------------ ----------- --------- --------------------

This analysis indicates that Option 2 will result in an overall cost
savings. Further, the incremental cost- effectiveness of Option 2
monitoring compared to Option 1 is a negative \$1,750/ton of HAP
emissions controlled, which indicates a cost savings above the MACT
floor option and is reasonable given these assumptions. However, there
are some fundamental assumptions that may affect this analysis, for
example, the amount of recovery credit generated by each program is
uncertain and we did not consider repair costs or production downtime
costs in our analysis. Therefore, we are co-proposing Option 1, the MACT
floor option, and Option 2 in the event that the costs and feasibility
of going beyond the floor are not reasonable. We are requesting comments
on this analysis and on these options.

Additionally, under both options, a delay in repair is allowed under the
proposed requirements if repair of the leak would require the process
unit served by the leaking heat exchanger to be shut down, and the
shutdown would result in greater HAP emissions than the projected HAP
emissions from the cooling tower leak or if the necessary parts are not
reasonably available. We request comments on other possible criteria for
delay of repair in addition to these. In addition, we are requesting
comments on another option for heat exchanger systems that cannot be
repaired without a shutdown that would allow delay of repair until the
next unit shutdown. This allowance could be contingent on factors such
as the level of HAP emissions from the cooling tower or the duration to
the next scheduled shutdown. Finally, we request comments on tracking
the HAP emissions that occur during the delayed repair and relationship
between this monitoring and emission measurement and the reportable
quantity requirements under CERCLA.

B. [How did we estimate residual risk]{.underline}?

EPA modeled available data on the emissions from petroleum refineries to
assess the risks associated with petroleum refinery HAP emissions after
compliance with the Refinery MACT 1 standard but prior to the proposed
MACT amendments for cooling towers. Consistent with previous residual
risk assessments, standard air toxics risk assessment practices and
principles were used to conduct assessments of potential chronic and
acute exposures and risks for both inhalation and non-inhalation
pathways. In addition, the potential for an adverse environmental effect
arising from these sources was also evaluated. Complete documentation
for the methods used and results from the risk assessment is available
in a report entitled, draft Residual Risk Assessment for MACT 1
Petroleum Refining Sources, which is available in the docket.

Emissions data for 153 petroleum refineries nationwide were developed
starting from the EPA's 2002 National Emissions Inventory (NEI),
incorporating site-specific emissions and source information which were
provided by the American Petroleum Institute (API) for 22 facilities.
The emissions database was published for public comment through an
Advanced Notice of Proposed Rulemaking (ANPRM). Comments and corrections
to the database received during the public comment period were evaluated
by technical reviewers for quality and consistency with engineering
data; valid corrections to the database were incorporated for an
additional 50 facilities (beyond the 22). No comments or corrections
were received on the emissions or source data for 81 facilities.[^2] The
153 refineries included in the database are believed to be all of the
sources in the category.

C. [What are the residual risks from petroleum refineries]{.underline}?

Table 2 of this preamble summarizes the results of the inhalation risk
assessment. These estimates characterize the lifetime risk of developing
cancer or noncancer health effects for individuals living within 50
kilometers (km) of any petroleum refinery.

Table 2. Risk Estimates Due to HAP Exposure Based on 70-Year Exposure
Duration

+------------------------------------------+---------------------------+
| Parameter                                | Results for Refinery MACT |
|                                          | 1 Source Category         |
+------------------------------------------+---------------------------+
| Maximum individual lifetime cancer risk  | 70                        |
| (in 1 million)                           |                           |
+------------------------------------------+---------------------------+
| Maximum hazard index^1^                  | 0.3                       |
|                                          |                           |
| (chronic respiratory effects)            |                           |
+------------------------------------------+---------------------------+
| Estimated size of population at risk:    | 90,000,000                |
+------------------------------------------+---------------------------+
| greater than 1-in-1 million              | 460,000                   |
+------------------------------------------+---------------------------+
| greater than 10-in-1 million             | 6,000                     |
+------------------------------------------+---------------------------+
| greater than 100-in-1 million            | 0                         |
+------------------------------------------+---------------------------+
| Annual cancer incidence (number of cases | 0.04-0.09                 |
| per year)                                |                           |
+------------------------------------------+---------------------------+

^1^ If the hazard index (HI) is calculated to be less than or equal to
1, then no adverse heath effects are expected as a result of the
exposure.

We estimate that approximately 90 million people live within 50 km of a
refinery. Results from the risk assessment indicate that none of the
facilities posed a cancer risk greater than 100-in-1 million.
Approximately 60 percent of the refineries have a maximum individual
lifetime cancer risk (MIR) of greater than 1-in-1 million, and about 14
percent are associated with a MIR greater than 10-in-1 million. The
highest MIR value at any facility is 70-in-1 million. The cumulative
cancer incidence from all MACT 1 refinery emission sources is estimated
to be between 0.04 and 0.09 cases per year, or 1 case every 11 to 25
years. Benzene, naphthalene, polycyclic organic matter, and ethylene
dibromide emissions are responsible for most of the estimated cancer
incidence. Since the benzene cancer unit risk estimate (URE) is reported
as a range of values, each end of which is considered to be equally
plausible, the range of incidence reflects calculated risks using either
end of the range, as well as different methods for extrapolating the
risks from subsets of facility emission estimates. Additionally, the
maximum noncancer hazard index (HI) associated with emissions from any
refinery is estimated to be less than 1. This allows us to conclude that
human inhalation exposures to pollution from Refinery MACT 1 sources are
without appreciable risk of chronic noncancer health effects, and that
direct atmospheric exposures of these pollutants to ecological receptors
should not result in any potential environmental impact.

We performed acute screening-level assessments of potential acute
impacts of concern on each facility and refined those assessments by
analyzing aerial photographs of facilities with potential exceedances of
acute benchmarks to determine which potential exceedances were truly
outside facility boundaries. The results indicated that 12 facilities
show a potential to exceed 1-hour California acute Reference Exposure
Levels (REL) for 3 pollutants (benzene, acrolein, and arsenic). The
acute 1-hour REL is defined as the concentration level at or below which
no adverse health effects are anticipated for a 1-hour exposure. Acute
REL values are designed to protect the most sensitive individuals in a
population by including margins of safety. The highest potential
exceedance of any REL was for acrolein, and the REL was exceeded by a
factor of 70. Other pollutants showing potential exceedances of the REL
value are benzene (exceeded by a factor of 40), and arsenic (exceeded by
a factor of 30). In spite of the fact that potential exceedances of
these 3 acute REL values are shown by this analysis, none of the
facilities investigated showed any potential to exceed available mild
1-hour Acute Exposure Guideline Levels (AEGL-1) for any of the modeled
pollutants. The AEGL-1 is the airborne concentration of a substance
above which it is predicted that the general population, including
susceptible individuals, could experience notable discomfort,
irritation, or certain asymptomatic nonsensory effects.

Given the definitions of the acute REL and the AEGL-1, it is reasonable
to conclude that (1) health effects in humans could occur as exposures
increase above the AEGL-1, and (2) exposures below the REL are very
unlikely to result in adverse health effects. Potential exposures in
between these values (which is what this analysis shows) are more
difficult to interpret in terms of health risk. That is, these potential
exposures are in the \"gray area\" of uncertainty where the true
threshold for adverse effects lies, and thus it is not clear if adverse
effects could actually occur at the levels determined by this analysis.
Further, we did not refine these results by incorporating actual
site-specific short-term emission variability into the analysis, so
these results are believed to be very conservative and should be
interpreted with care.

We also performed a screening-level multipathway risk assessment on the
emissions of mercury, cadmium, lead, and polycyclic aromatic
hydrocarbons (PAH), all compounds which are considered to be persistent
and bioaccumulative HAP. Based on the results of this screening,
noncancer human health risks due to the ingestion of these pollutants
were all below levels considered to be without appreciable risk of
adverse health effect. One of these pollutants, PAH, showed a potential
to cause individual cancer risks as high as 40-in-1 million, exceeding
1-in-1 million, but less than 100-in-1 million. However, because of our
inability to accurately speciate and estimate risks for individual
compounds within the PAH class, we believe that this result is highly
conservative, and that the true risks associated with these PAH are
likely to be less than 1-in-1 million.

For the ecological assessment, two exceedances (cadmium and PAH) of
ecological toxicity benchmarks were observed when examining the
predicted TRIM.FaTE media concentrations (see Draft Residual Risk
Assessment for MACT I Petroleum Refining Sources document). Given the
conservative nature of the screening scenario, the results of the
comparisons and a review of additional information available on the
ecological toxicity of cadmium and PAH, we concluded that it is highly
unlikely that these two exceedances are of concern. Overall, the
potential for emissions from petroleum refinery sources to result in an
adverse environmental impact is likely to be very low for all persistent
bioaccumulative HAP emitted.

D. [What are the uncertainties in risk assessments]{.underline}?

Uncertainty and the potential for bias are inherent in all risk
assessments, including those performed for the petroleum refineries
source categories affected by this proposal. A full discussion of
uncertainties is found in the Draft Residual Risk Assessment for
Petroleum Refining Sources (August 2007), available in the docket.

Although the development of the risk and technology review (RTR)
database involved quality assurance/quality control processes, the
accuracy of emissions values will vary depending on the source of the
data present, incomplete or missing data, errors in estimating emissions
values, and other factors. Our review of the data indicates that there
may be a low bias in reported emissions for many facilities. It appears
that data from several processes and operations are not included in the
reported emissions from many facilities. These include exclusion of
upset, malfunction, startup, and shutdown events as well as omission of
emissions sources that are unexpected, not measured, or not considered
in inventories, such as leaks in heat exchanger systems; emissions from
process sewers and wastewater systems; fugitive emissions from delayed
coking units; and emissions from tank roof landings. Further, the
emissions values considered in this analysis are annual totals for a
single calendar year (2002) and do not reflect actual fluctuations
during the course of the year, as well as variations from year to year.
Finally, although we have performed a significant amount of quality
control on the data set, for many facilities the physical
characteristics (i.e., stack height, physical location) of the reported
sources may be inaccurate for detailed risk characterization purposes.

We recently discovered that certain area source location attributes may
have been incorrectly incorporated into our atmospheric dispersion
simulations, resulting in a positional translation error which may
locate certain emission points closer to or farther from
potentially-exposed populations. While the impact of this error has not
been fully evaluated, we believe that it will not dramatically alter the
MIR value for the source category, and that it will have very little
impact on the total cancer incidence. Nonetheless, we will investigate
and correct this error between proposal and promulgation of the final
petroleum refineries MACT 1 residual risk decision and will consider any
impact of this error in our final decision.

The uncertainties in our risk assessment can be generally divided into
uncertainties in our ability to characterize exposures and uncertainties
in our ability to characterize dose-response. We believe that the
primary source of uncertainty in our exposure assessment is the
uncertainty in the underlying emissions data, which are generally
thought to be biased low, based on recent studies indicating that
emission points such as cooling towers and wastewater treatment units
are historically underestimated or even omitted from petroleum refinery
emission inventories. Elsewhere in this notice, we request comment on
methods that might reduce these emission uncertainties through moderate
efforts to conduct ambient monitoring. The assessment uses toxicological
dose-response values typically extrapolated from high-dose animal
exposure or occupational exposures, to estimate risk. Consistent with
EPA guidance, RfCs are developed by using order-of-magnitude factors to
account for uncertainties in developing values protective of sensitive
subpopulations. Most of the URE in this assessment were developed using
linearized low-dose extrapolation. Risks could be overestimated if the
true dose-response relationship (which is usually unknown) is sublinear.
Impacts have been extrapolated from short-duration, high-dose animal or
occupational exposures to longer durations and lower doses, using
uncertain interspecies scaling methods. In general, EPA considers these
URE\'s to be upper-bound estimates based on the method of extrapolation,
meaning they represent a plausible upper limit to the true value. (Note
that this is usually not a true statistical confidence limit.) The true
risk is therefore likely to be less, could be as low as zero, but also
could be greater. As previously noted, benzene cancer risks were
estimated from the reported URE range, which is considered to be based
on maximum likelihood exposure and risk estimates.

E. [What is our proposed decision under CAA Section 112(f)]{.underline}?

Based on the emissions data we have, we estimate that the MIR associated
with exposures to HAP emissions from the sources covered by the Refinery
MACT 1 rule is 70-in-1 million. Because the MIR is less than 100-in-1
million, the risk is acceptable. However, since the MIR is greater than
1-in-1 million, we must consider whether to require additional controls
to protect public health with an ample margin of safety.

In making the ample margin of safety determination, we consider the
estimate of health risk and other health-related information (such as
the weight of evidence for carcinogenicity or the severity of the
noncancer health effect) along with additional factors relating to the
appropriate level of control, including costs and economic impacts of
controls, technological feasibility, uncertainties, and other relevant
factors, consistent with the approach of the 1989 Benzene NESHAP, as
summarized earlier.

In developing our proposed options under CAA section 112(f)(2), we
considered control options for each of the Refinery MACT 1 emissions
sources. In developing the control options, we wanted to target further
emission reductions to the extent possible to reduce public health
risks. The following provides a discussion of the control options that
we evaluated for each of the Refinery MACT 1 emission sources.

1\. [Control Options Considered]{.underline}

a\. Miscellaneous Process Vents, Gasoline Loading Racks, and Marine
Vessel Loading Control Measures

Group 1 miscellaneous process vents and transfer loading operations
(gasoline loading racks and marine vessel loading) are regulated by
performance standards based on the use of technologies such as thermal
oxidizers and carbon. We did not identify any other technically feasible
control technologies that would reduce HAP emissions beyond these
levels. Therefore, the only way to reduce residual risk would be to
change the applicability (i.e., certain Group 2 emission points under
the original rule would become Group 1 emission points under a revised
rule). We could not identify any cost-effective control options; the
control option based on lowering the Group 1 thresholds exceeds \$40,000
per ton of HAP reduced and \$400,000 per ton of benzene reduced.

b\. Equipment Leak Control Measures

For equipment leaks, we evaluated reducing the leak definition and
requiring monitoring of open-ended lines. The cost-effectiveness of this
option is approximately \$20,000 per ton of HAP reduced and
approximately \$300,000 per ton of benzene reduced. We rejected these
options due to their unreasonable cost-effectiveness.

c\. Storage Vessel Control Measures

For storage vessels, we evaluated two control alternatives for Group 1
external floating roof storage vessels. First, we considered requiring a
gasketed sliding cover or a flexible fabric sleeve and requiring a
gasketed float or other device which closes off the liquid surface from
the atmosphere for slotted guide poles. Next, we considered requiring
geodesic domes. The slotted guide pole sleeve control option would
reduce HAP by 1,046 tpy and benzene emissions by 105 tpy. The annualized
cost of this control option would be completely offset by the value of
the organic products that would not be emitted by the addition of
controls. The geodesic dome control option is not cost-effective when
added to the proposed requirement for slotted guide pole sleeves.

d\. Wastewater Control Measures

For refinery wastewater systems, the refinery MACT standard is based on
the BWON requirements (55 FR 8346, 58 FR 3095). The BWON was developed
under the two-step Benzene NESHAP approach and at that time we concluded
that the controls provided an ample margin of safety. Because the BWON
was incorporated by reference into the Petroleum Refineries MACT
standard, we must now determine whether the BWON protects public health
with an ample margin of safety. We believe that additional controls may
be necessary to ensure an ample margin of safety.

We worked with industry to improve the emissions data used in the risk
assessment. As part of this effort, refinery trade organizations
provided EPA with detailed benzene emissions data from 22 petroleum
refineries expected to be representative of the industry (see docket).
Most refineries reported zero or minimal emissions from wastewater
systems. For systems with EBU operating at 92 percent benzene reduction
efficiency (the benzene reduction we estimated would be achieved in the
BWON), we would expect benzene emissions on the order of 3 to 10 tpy,
depending on the load into the system. The wastewater emissions reported
the 22 refineries are much less than this amount, approximately 20 tpy,
which leads us to believe that the emission estimates exclude or
significantly under-report benzene emissions from the EBU.

For well-operated EBU, the benzene emissions are expected to be small;
however, there are no requirements in the Refinery MACT 1 rule or the
BWON to demonstrate the proper performance of EBU. Since the BWON was
promulgated, we have developed procedures and test methods to verify the
performance of EBU.

Analysis of the potential emissions and associated risks from EBU when
the biological treatment efficiency is less than 90 percent indicates
that these sources could contribute significantly to risk. Therefore, we
are evaluating a control option that the EBU demonstrate a fraction
biodegraded of 90 percent or greater for benzene through an initial
performance demonstration. This would be coupled with weekly monitoring
of process parameters.

e\. Cooling Tower Control Measures

The Refinery MACT 1 rule does not include provisions for cooling towers;
we are proposing MACT requirements for cooling towers to address total
organic HAP emissions under CAA section 112(d)(2). Those requirements
are described in section IV.A of this preamble. In that section, we
discuss our floor and beyond the floor analysis pursuant to CAA section
112(d)(2) and (d)(3) . We could not identify any additional control
requirements that could cost-effectively reduce emissions from cooling
towers beyond the options described above in our beyond-the-floor
analysis.

More information of our evaluation of the control options considered for
the Refinery MACT 1 emission sources is contained in memoranda in the
docket.

f\. Fenceline Monitoring

Numerous commenters on the ANPR for Phase II risk and technology review,
including the Residual Risk Coalition representing the American
Petroleum Institute, expressed concern about the quality and accuracy of
emissions data available to conduct refined risk assessments. Based on
our review of these data, we agree that there appears to be significant
uncertainty, not only in identifying and characterizing emissions
sources within facilities, but also in the amount and types of HAP
emitted. In addition to inherent uncertainty in the development and use
of emission factors, our review of the data indicates that there may be
a low bias in reported emissions, as discussed earlier. Additional
discussion of the potential low bias in emission estimates is available
in the docket.

Our concerns regarding the potential low bias in the emission estimates
leads us to request public comment on requiring fenceline monitoring of
ambient benzene. A fenceline monitoring program may provide an effective
method to assess the general magnitude of uncertainty in facility
emissions estimates for benzene. Additional information on fenceline
monitoring may be found in a technical memorandum in the docket.

2\. [Regulatory Decisions under CAA section 112(f)(2)]{.underline}

a\. Regulatory Decision for Storage Vessels

We are proposing two options for our rulemaking on whether to establish
additional emission standards to protect public health with an ample
margin of safety. Option 1 is to maintain the current level of control
in the Refinery MACT 1 rule with no further modifications. Option 2
includes controls for storage vessels.

Impacts of the proposed control option requiring existing storage
vessels with external floating roofs to install and operate a gasketed
sliding cover or a flexible fabric sleeve and a gasketed float or other
device which closes off the liquid surface from the atmosphere for
slotted guide poles were evaluated and are presented in Table 3 of this
preamble along with the associated costs and emissions reductions. These
controls prevent the loss of products from storage vessels. Therefore,
the control costs are offset by the increased product sales that are
available by this pollution prevention. The VOC credit was calculated to
be \$480 per ton of VOC reduced, resulting in a net cost savings
presented below.

Table 4 of this preamble presents the risk reduction associated with the
control option for storage vessels.

Table 3. Cost and Emissions Impacts of Option 2 for Storage Vessels

<table>
<colgroup>
<col style="width: 15%" />
<col style="width: 4%" />
<col style="width: 12%" />
<col style="width: 3%" />
<col style="width: 12%" />
<col style="width: 5%" />
<col style="width: 8%" />
<col style="width: 9%" />
<col style="width: 3%" />
<col style="width: 11%" />
<col style="width: 9%" />
<col style="width: 3%" />
</colgroup>
<tbody>
<tr class="odd">
<td>Control Require-ment</td>
<td colspan="2"><p>Total Capital Investment</p>
<p>($ million)</p></td>
<td colspan="2">Total Annualized Cost without Recovery ($ million)</td>
<td colspan="2">Product Recovery Credit ($ million)</td>
<td colspan="2">Total Annual-ized Cost ($ million)</td>
<td><p>HAP Emis-sions</p>
<p>(tpy)</p></td>
<td colspan="2">Average Cost per Ton of HAP ($/ton)</td>
</tr>
<tr class="even">
<td>Option 1 (Baseline)</td>
<td colspan="2">0</td>
<td colspan="2">0</td>
<td colspan="2">0</td>
<td colspan="2">0</td>
<td>1,867</td>
<td colspan="2">0</td>
</tr>
<tr class="odd">
<td>Option 2 Storage Vessel Controls</td>
<td colspan="2">2.76</td>
<td colspan="2">1.1</td>
<td colspan="2">-4.6</td>
<td colspan="2">-3.5</td>
<td>821</td>
<td colspan="2">-3,340</td>
</tr>
<tr class="even">
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="3"></td>
<td></td>
</tr>
<tr class="odd">
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="2"></td>
<td colspan="3"></td>
<td></td>
</tr>
</tbody>
</table>

Table 4. Risk Impacts of Regulatory Alternative for Storage Vessels

+--------------+-------------+---------------------+------------------+
| Parameter    |             |                     |                  |
+--------------+-------------+---------------------+------------------+
|              |             | Option 1            | Option 2         |
|              |             |                     |                  |
|              |             | Baseline            | Storage Vessel   |
|              |             |                     | Control          |
+--------------+-------------+---------------------+------------------+
| Risk to Most | Cancer (in  | 70                  | 70               |
| Exposed      | 1 million)  |                     |                  |
| Individual   |             |                     |                  |
+--------------+-------------+---------------------+------------------+
|              | Noncancer   | .3                  | .3               |
|              | (HI)        |                     |                  |
+--------------+-------------+---------------------+------------------+
| Size of      | \> 100-in-1 | 0                   | 0                |
| Population   | million     |                     |                  |
| at Cancer    |             |                     |                  |
| Risk^1^      |             |                     |                  |
+--------------+-------------+---------------------+------------------+
|              | \> 10-in-1  | 6,000               | 5,100            |
|              | million     |                     |                  |
+--------------+-------------+---------------------+------------------+
|              | \> 1-in-1   | 460,000             | 393,000          |
|              | million     |                     |                  |
+--------------+-------------+---------------------+------------------+
| Number of    | \> 100-in-1 | 0                   | 0                |
| Plants at    | million     |                     |                  |
| Cancer Risk  |             |                     |                  |
| Level^1^     |             |                     |                  |
+--------------+-------------+---------------------+------------------+
|              | \> 10-in-1  | 21                  | 15               |
|              | million     |                     |                  |
+--------------+-------------+---------------------+------------------+
|              | \> 1-in-1   | 96                  | 91               |
|              | million     |                     |                  |
+--------------+-------------+---------------------+------------------+
| Population   |             | 0                   | 0                |
| with HI \>   |             |                     |                  |
| 1^2^         |             |                     |                  |
+--------------+-------------+---------------------+------------------+
| No of Plants |             | 0                   | 0                |
| with HI \> 1 |             |                     |                  |
+--------------+-------------+---------------------+------------------+
| Cancer       |             | 0.04-.09            | 0.03-.08         |
| Incidence    |             |                     |                  |
+--------------+-------------+---------------------+------------------+
| Cancer       |             | NA                  | 10-25            |
| Incidence    |             |                     |                  |
| Reduction    |             |                     |                  |
| (Percent)    |             |                     |                  |
+--------------+-------------+---------------------+------------------+
| HAP Emission |             | NA                  | 15               |
| Reduction    |             |                     |                  |
| (Percent)    |             |                     |                  |
+--------------+-------------+---------------------+------------------+

^1^ Population risks and plant risk bin estimates are based on utilizing
the high end of the reported cancer URE range for benzene. These
estimates may be as much as 30 percent lower when estimated using the
lower end of the benzene URE range.

^2^ If the Hazard Index (HI) is calculated to be less than or equal to
1, then no adverse health effects are expected as a result of the
exposure.

Under option 1, we are proposing to make no changes to the current
Refinery MACT rule, instead proposing to find that the current level of
control called for by the existing MACT standard represents both an
acceptable level of risk (the cancer risk to the most exposed individual
is approximately 70-in-1 million) and provides public health protection
with an ample margin of safety. This proposed finding is based on
considering the uncertainty of the cost impacts of further control for
individual refineries and the relatively small reductions in health
risks that are achieved by further control.

The Agency would conclude under proposed option 1 that the \$3.5 million
per year nationwide cost savings is uncertain and that some refineries
may have positive net costs under Option 2, and that these costs would
be unreasonable given the minor associated risk reductions. Baseline
cancer incidence under the current Refinery MACT 1 rule is estimated at
0.04 to .09, or 0.07 cases per year, on average. Proposed Option 2 would
reduce incidence by about 0.01 cases per year. Statistically, this level
of risk reduction means that Option 2 would prevent 1 cancer case every
100 years. Accordingly, if we were to conclude that there were not cost
savings, the cost of this option could be considered to be
disproportionate to the level of incidence reduction achieved. In
addition, the Agency proposes to conclude that there are no changes in
the distribution of risks reflected in Table 4 of this preamble (i.e.,
the MIR is not reduced from 70-in-1 million by additional control), and
there are no noncancer HI values above 1. Consequently, under Option 1,
we are proposing that it is not necessary to impose any additional
controls on the industry to provide an ample margin of safety to protect
public health.

Alternatively, we are also proposing that Option 2 provides an ample
margin of safety to protect public health. This option reduces HAP
emissions and risks beyond the current MACT standard using controls that
are technically and economically feasible and that pose no adverse
environmental impacts. We estimate that these changes would reduce the
number of people at cancer risk greater than one in a million by 67,000
individuals and the cancer incidence by 0.01 cases per year (i.e.,
prevent one cancer case every 100 years). Option 2 would reduce
emissions of VOC by 9,500 tpy. Reducing VOC provides the added benefit
of reducing ambient concentrations of ozone and may reduce fine
particulate matter. The annualized cost impacts of Option 2 are
estimated to be a cost savings of \$3.5 million. Our economic analysis
(summarized later in this preamble) indicates that this cost will have
little impact on the price and output of petroleum products.

b\. Regulatory Decision for EBU

We are proposing two options for our rulemaking on whether to establish
additional emission standards to protect public health with an ample
margin of safety. Option 1 maintains the current level of control in the
Refinery MACT 1 rule with no further modifications. Option 2 requires
refinery owners and operators of EBU to demonstrate and ensure a
fraction biodegraded of 90 percent or greater for benzene through an
initial performance demonstration coupled with weekly monitoring of
process parameters to ensure the EBU are achieving the ample margin of
safety as intended by the BWON rule. Impacts of the proposed Option 2
are presented in Table 5.

Table 5. Cost and Emissions Impacts of Option 2 for EBU

+-------------+--------------+--------------+-----------+------------+
| Control     | Total        | Total        | HAP       | Average    |
| Requirement | Installed    | Annualized   | Emissions | Cost Per   |
|             | Capital Cost | Cost         |           | Ton of HAP |
|             |              |              | (tpy)     | (\$/Ton)   |
|             | (\$ Million) | (\$ million) |           |            |
+-------------+--------------+--------------+-----------+------------+
| Option 1    | 0            | 0            | 5,000     | 0          |
| (Baseline)  |              |              |           |            |
+-------------+--------------+--------------+-----------+------------+
| Option 2    | 0            | 1.1          | 3,200     | 600        |
|             |              |              |           |            |
| EBU         |              |              |           |            |
| Performance |              |              |           |            |
| Dem         |              |              |           |            |
| onstra-tion |              |              |           |            |
| and         |              |              |           |            |
|             |              |              |           |            |
| Monitoring  |              |              |           |            |
+-------------+--------------+--------------+-----------+------------+

Impacts presented in Table 5 assume that 50 percent of EBU may degrade
benzene at an efficiency of 80 percent. In the development of the BWON,
we estimated that EBU would achieve between 88 to 93 percent control
efficiency (Final NESHAP Standards for Waste Operations: Basis for
Impact Calculations, Feb. 1990), on average, and made the finding that
the reductions achieved from EBU would result in acceptable risk, and we
did not require further reductions as part of our ample margin of safety
decision. At that time, we had no consistent method of characterizing
the performance of these treatment systems. Since the promulgation of
the Refinery MACT 1 rule, we have promulgated procedures in appendix C
of 40 CFR Part 63 to estimate the performance of biological treatment
systems and have required the use of appendix C to demonstrate treatment
efficiencies on other industries that use biological treatment systems.
Our experience with other industries suggest that, while high biological
treatment efficiencies can be achieved for low volatility, oxygenated
compounds, achievement of high control efficiencies for benzene and
other aromatic compounds is more difficult. As noted previously, many
refineries who provided data to the Agency reported zero or minimal
emissions from wastewater treatment systems, many of which employ EBU
for treatment. For EBU operating at 92 percent benzene reduction
efficiency, we would expect benzene emissions ranging from 3 to 10
tons/year. The emissions reported by the 22 refineries are much less
than this amount, which leads us to believe that the emission estimates
exclude or significantly under-report benzene emissions from EBU. We
specifically request comments on additional data that would address
these concerns. Further, the use of appendix C by refineries at the
present time is very limited, and, therefore, there is no data to either
confirm or refute the validity of the original assumption of 92 percent
made under the BWON.

The costs are based on the initial performance demonstration averaged
over 5 years, so that the annual cost of the performance evaluation was
\$5,000/year. Once the performance evaluation is completed, refineries
are expected to develop operating limits for the minimum MLVSS
concentration and the maximum food to microorganism ratio, which must be
determined on a weekly basis. Although owners and operators of EBU are
expected to routinely conduct these analyses, we estimated that an
additional cost of \$5,000/year would be incurred for these analyses and
the associated recordkeeping and reporting requirements. Additionally,
we assumed that by altering the operating characteristics of the unit
(e.g., increasing system mixing characteristics, increasing biomass or
submerged aeration), we assumed that all of the units not originally
achieving 90 percent treatment efficiency could achieve 90 percent
treatment efficiency at no cost. EPA understands that significant
material and/or labor costs actually might be incurred by
owners/operators who implement treatment process changes such as adding
or modifying aerators, or implementing other process improvements, and
specifically requests comment on this assumption. Nevertheless, we
currently estimate that refineries using EBU for treatment of affected
wastewater streams would incur, on average, a cost of \$10,000/year over
the first 5 years.

Table 6 presents the estimated risk reductions for the EBU control
Option. Table 6 also presents the risk impacts assuming a hypothetical
baseline based on the addition of emissions from cooling towers and
wastewater operations to the RTR dataset. It is important to note that
the risk impacts resulting from a higher HAP baseline estimated assuming
that 50 percent of EBU are achieving an average of 80 percent, rather
than 92 percent control, and that this is an assumption (an estimate of
hypothetical emissions) based on our judgment of what could be occurring
in the industry, and is not based on actual emissions estimates or
modeling. EPA specifically requests comment and data related to the
validity of this assumption. The baseline benzene emissions were assumed
to increase from 136 tpy benzene (in the RTR database) to 388 tpy
benzene, and the reductions achieved as a result of imposing
demonstration requirements leading to better EBU process controls were
calculated to be 138 tpy benzene. Finally, based on a ratio of 7.7
percent benzene to HAP for wastewater, we calculated reductions of 1,800
tpy HAP from this option. Additionally, we also increased the adjusted
baseline to account for unreported cooling tower emissions of 285 tpy
benzene. Accordingly, risk impacts for the baseline were scaled
linearly, and the EBU controls were estimated to reduce cancer incidence
from the hypothetical baseline by .01 to .02. It should be noted that
this is not a rigorous risk analysis, but a rough estimate of risk
impacts based on projected wastewater emissions.

Table 6. Risk Impacts of Regulatory Alternative for EBU

+-----------+-----------+----------+----------------+----------------+---+
| Parameter |           | RTR      | Option 1       | Option 2       |   |
|           |           | Baseline | Adjusted       |                |   |
|           |           |          | (Hypothetical) | EBU Controls   |   |
|           |           |          | Baseline       | (Hypothetical) |   |
+-----------+-----------+----------+----------------+----------------+---+
| Risk to   | Cancer    | 70       | 70             | 70             |   |
| Most      | (in 1     |          |                |                |   |
| Exposed   | million)  |          |                |                |   |
| I         |           |          |                |                |   |
| ndividual |           |          |                |                |   |
+-----------+-----------+----------+----------------+----------------+---+
|           | Noncancer | 0.3      | 0.3            | 0.3            |   |
|           | (HI)      |          |                |                |   |
+-----------+-----------+----------+----------------+----------------+---+
| Size of   | \>        | 0        | 0              | 0              |   |
| P         | 100-in-1  |          |                |                |   |
| opulation | million   |          |                |                |   |
| at Cancer |           |          |                |                |   |
| Risk^1^   |           |          |                |                |   |
+-----------+-----------+----------+----------------+----------------+---+
|           | \>        | 6,000    | 10,500         | 9,300          |   |
|           | 10-in-1   |          |                |                |   |
|           | million   |          |                |                |   |
+-----------+-----------+----------+----------------+----------------+---+
|           | \> 1-in-1 | 460,000  | 805,000        | 716,000        |   |
|           | million   |          |                |                |   |
+-----------+-----------+----------+----------------+----------------+---+
| Number of | \>        | 0        | 0              | 0              |   |
| Plants at | 100-in-1  |          |                |                |   |
| Cancer    | million   |          |                |                |   |
| Risk      |           |          |                |                |   |
| Level^1^  |           |          |                |                |   |
+-----------+-----------+----------+----------------+----------------+---+
|           | \>        | 21       | 41             | 36             |   |
|           | 10-in-1   |          |                |                |   |
|           | million   |          |                |                |   |
+-----------+-----------+----------+----------------+----------------+---+
|           | \> 1-in-1 | 96       | 108            | 104            |   |
|           | million   |          |                |                |   |
+-----------+-----------+----------+----------------+----------------+---+
| P         |           | 0        | 0              | 0              |   |
| opulation |           |          |                |                |   |
| with HI   |           |          |                |                |   |
| \> 1^2^   |           |          |                |                |   |
+-----------+-----------+----------+----------------+----------------+---+
| No of     |           | 0        | 0              | 0              |   |
| Plants    |           |          |                |                |   |
| with HI   |           |          |                |                |   |
| \> 1      |           |          |                |                |   |
+-----------+-----------+----------+----------------+----------------+---+
| Cancer    |           | 0        | 0.07-.16       | 0.06-.14       |   |
| Incidence |           | .04-0.09 |                |                |   |
+-----------+-----------+----------+----------------+----------------+---+
| Cancer    |           |          | NA             | 15             |   |
| Incidence |           |          |                |                |   |
| Reduction |           |          |                |                |   |
| (Percent) |           |          |                |                |   |
+-----------+-----------+----------+----------------+----------------+---+
| HAP       |           |          | NA             | 11             |   |
| Emission  |           |          |                |                |   |
| Reduction |           |          |                |                |   |
| (Percent) |           |          |                |                |   |
+-----------+-----------+----------+----------------+----------------+---+

^1^ Population risks and plant risk estimates are based on utilizing the
high end of the reported cancer URE range for benzene. These estimates
may be as much as 30 percent lower when estimated using the lower end of
the benzene URE range.

  ---------------- ---------------- ------------------- -------------------
  ^2^                                                   

                                                        

                                                        

                                                        

                                                        

                                                        

                                                        

                                                        

                                                        

                                                        

                                                        

                                                        

                                                        

                                                        

                                                        
  ---------------- ---------------- ------------------- -------------------

1 If the Hazard Index (HI) is calculated to be less or equal to 1, then
no adverse health effects are expected as a result of the exposure.

Under Option 1, we are proposing to make no changes to the current
Refinery MACT rule, and are proposing that the current level of control
under the existing MACT standard represents both an acceptable level of
risk (the cancer risk to the most exposed individual is approximately
70-in-1 million) and provides public health protection with an ample
margin of safety. This proposed finding is based on the existing data
(emissions estimates from 22 refineries, the NEI, and from public review
of the NEI data) that indicate that risks posed wastewater treatment
systems are low and that further reduction of such low risk is not
warranted and is not necessary to achieve an ample margin of safety.

We are also proposing that Option 2 provides an ample margin of safety
to protect public health. This option may reduce HAP emissions and risks
beyond the current MACT standard using controls that are technically and
economically feasible and that pose no adverse environmental impacts.
Further, the option addresses the uncertainty in emissions estimates by
requiring that owners and operators of EBU demonstrate their systems are
effective as reflected by the low reported emissions estimates for
wastewater treatment systems. We believe this option addresses the
consideration of uncertainty in the ample margin of safety decision.

We estimate that these changes could reduce the number of people at
cancer risk greater than one in a million by 89,000 individuals. In
addition, Option 2 could reduce the cancer incidence by between 0.01 and
0.02 cases per year (i.e., prevent one cancer case every 100 to 50
years), depending on the accuracy of our assumptions, and resulting in a
cost of \$110 to \$55 million per cancer case avoided. The annualized
cost impacts of Option 2 are estimated at 1.1 million. Our economic
analysis (summarized later in this preamble) indicates that this cost
will have little impact on the price and output of petroleum products.

c\. Regulatory Decision for Cooling Towers

Section 112(f)(2) of the CAA requires that we evaluate residual risk and
set standards as necessary to protect human health with an ample margin
of safety within 8 years of promulgation of a MACT standard. We are
performing the CAA section 112(f)(2) review for all petroleum refinery
MACT 1 sources, including cooling towers, in this proposal.

As stated previously, the petroleum refinery risks are now acceptable.
We believe that with the controls proposed as meeting CAA sections
(d)(2) and (d)(3), no additional controls for cooling towers are needed
to provide an ample margin of safety under CAA section (f)(2). In the
final rule we will select MACT as one of these two options or other
options that are a logical outgrowth of public comments. We will then
assess the risk that remains and also perform the ample margin of safety
analysis in the manner described above.

F. [What is EPA proposing pursuant to CAA section
112(d)(6)]{.underline}?

Section 112(d)(6) of the CAA requires us to review and revise MACT
standards, as necessary, every 8 years, taking into account developments
in practices, processes, and control technologies that have occurred
during that time. This authority provides us with broad discretion to
revise the MACT standards as we determine necessary, and to account for
a wide range of relevant factors.

We do not interpret CAA section 112(d)(6) as requiring another analysis
of MACT floors for existing and new sources. Rather, we interpret the
provision as essentially requiring us to consider developments in
pollution control in the industry ("taking into account developments in
practices, processes, and control technologies"), and assessing the
costs of potentially stricter standards reflecting those developments
(69 FR 48351). As the U.S. Court of Appeals for the District of Columbia
Circuit has found regarding similar statutory provisions directing EPA
to reach conclusions after considering various enumerated factors, we
read this provision as providing EPA with substantial latitude in
weighing these factors and arriving at an appropriate balance in
revising our standards. This discretion also provides us with
substantial flexibility in choosing how to apply modified standards, if
necessary, to the affected industry.

In an earlier rulemaking, we elaborated on how we expect we would
address the need for future reviews under certain circumstances and our
position regarding when revisions may be likely under CAA section
112(d)(6). For more information on this subject, see Nation Emission
Standards for Hazardous Air Pollutants for Organic Hazardous Air
Pollutants from the Synthetic Organic Chemical Manufacturing Industry
(71 FR 34437-34438, June 14, 2006).

We could not identify any other developments in practices, processes,
and control technologies for Refinery MACT 1 sources. Therefore, as a
result of this CAA section 112(d)(6) review, we are proposing the same
two options as we proposed to meet section 112(f)(2). Based on the
uncertainty of the cost of control for individual refineries and the
relatively small reductions in health risks that are achieved by these
controls, we are proposing that these controls are not necessary under
112(d)(6). Alternately, if we conclude in the final rule that there are
cost savings associated with requiring slotted guidepole controls for
storage vessels, we are proposing to require those controls pursuant to
CAA section 112 (d)(6).

The consent decree also requires us to consider and address the
application of subpart A to subpart CC of part 63, as appropriate. The
requirements of 40 CFR part 63, subpart A are contained in Table 6 of 40
CFR part 63, subpart CC. As a result of our review, no changes are
currently proposed to Table 6 of the rule. However, as discussed in
section V of this preamble, we are requesting comments on entries to the
table that may be confusing to owners and operators.

**V. Request for Comments**

We request comment on all aspects of the proposed rule. All significant
comments received during the comment period will be considered in the
development and selection of the final rule. In addition to general
comments on the proposed options, we particularly request comments and
data on the following issues. Comments must provide supporting
documentation in sufficient detail to allow characterization of the
quality and representativeness of the data or information.

1\. Fenceline Monitoring

Based on the residual risk results, one of the primary risk drivers from
the Refinery MACT 1 emission sources is benzene. The primary releases of
benzene are fugitive emissions from process equipment, wastewater
treatment, storage tanks, and loading operations and generally occur
near ground level. Thus, the highest benzene concentrations outside the
facility will likely occur near ground level at the property boundaries.
Consequently, monitoring at the property boundary (fenceline) would
provide a measure of the annual average benzene concentrations
immediately surrounding the refinery, which might be useful in efforts
to eliminate uncertainties in emissions estimates.

As noted in section IV.H of this preamble, we are requesting comment on:
the need for a fenceline monitoring program, potential monitoring
methods (e.g., diffusive sampling or alternative active sampling
methods, alternative sorbents for measuring HAP other than benzene),
monitor siting, monitoring frequency, feasibility of various monitoring
approaches/methods, sampling and analytical precision and accuracy,
reliability of monitoring methods and devices, consideration of
non-facility related emissions, and sampling and analytical costs.

2\. Test Methods for Wastewater

We are also requesting comment on the applicability and feasibility of
Method 5220 for the measurement of chemical oxygen demand (COD) in
wastewater treated by EBU and alternative COD methods.

3\. Applicability of Subpart A to Subpart CC

In addition, we request comments on Table 11 of the Appendix to subpart
CC of 40 CFR part 63. The Appendix to subpart CC addresses the
application of the 40 CFR part 63 General Provisions in subpart A to
subpart CC of 40 CFR part 63. We have tried to make the Appendix to
subpart CC consistent with the Appendix A in subpart UUU, the other 40
CFR part 63 MACT standard affecting petroleum refineries.

**VI. Statutory and Executive Order Reviews**

A. [Executive Order 12866: Regulatory Planning and Review]{.underline}

Under Executive Order 12866 (58 FR 51735, October 4, 1993), this action
is a "significant regulatory action" because it may raise novel legal or
policy issues. Accordingly, EPA submitted this action to the Office of
Management and Budget (OMB) for review under Executive Order 12866, and
any changes made in response to OMB recommendations have been documented
in the docket for this action.

B. [Paperwork Reduction Act]{.underline}

The information collection requirements in the proposed amendments to
the NESHAP for Petroleum Refining (40 CFR part 63, subpart CC) will be
submitted for approval to OMB under the Paperwork Reduction Act, 44
U.S.C. 3501, [et]{.underline} [seq]{.underline}. A separate notice
seeking public comment on these information collection requirements will
be published in the **Federal Register**.

Burden means the total time, effort, or financial resources expended by
persons to generate, maintain, retain, or disclose or provide
information to or for a Federal agency. This includes the time needed to
review instructions; develop, acquire, install, and utilize technology
and systems for the purposes of collecting, validating, and verifying
information, processing and maintaining information, and disclosing and
providing information; adjust the existing ways to comply with any
previously applicable instructions and requirements; train personnel to
be able to respond to a collection of information; search data sources;
complete and review the collection of information; and transmit or
otherwise disclose the information.

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 EPA\'s regulations
in 40 CFR part 63 are listed in 40 CFR part 9.

C. [Regulatory Flexibility Act]{.underline}

The Regulatory Flexibility Act 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 would not
have a significant economic impact on a substantial number of small
entities. Small entities include small businesses, small not-for-profit
enterprises, and small governmental jurisdictions.

For the purposes of assessing the impacts of this proposed rule on small
entities, small entity is defined as: (1) a small business that meets
the Small Business Administration size standards for small businesses at
13 CFR 121.201 (a firm having no more than 1,500 employees and no more
than 125,000 barrels per day of capacity of petroleum-based inputs[^3],
including crude oil or bona fide feedstocks for NAICS code 32411); (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 which is independently owned and operated and is not dominant
in its field.

After considering the economic impacts of this proposed rule on small
entities, I certify that this action will not have a significant
economic impact on a substantial number of small entities. Based on our
analyses of both options, the amendments would either result in a
nationwide net cost of about \$1.0 million or achieve a nationwide net
savings (i.e., a return) of about \$4.0 million per year due to
reductions in product losses. Only one affected small firm would incur
net costs as a result of the proposed amendments; all other small or
large firms owning affected refineries would have net savings.  Net
costs for the affected small firm are well below 0.01 percent of its
revenue; therefore, no adverse economic impacts are expected for any
small entity. Thus, the costs associated with the proposal would not
result in any "significant" adverse economic impact for any small
entity.

Although the proposed rule will not have a significant economic impact
on a substantial number of small entities, we nonetheless tried to
reduce the impact of the proposed rule on small entities. We held
meetings with industry trade associations and company representatives to
discuss the proposed rule and have included provisions for small
facilities that address their concerns. We continue to be interested in
the potential impacts of the proposed action on small entities and
welcome comments on issues related to such impacts.

D. [Unfunded Mandates Reform Act]{.underline}

Title II of the Unfunded Mandates Reform Act of 1995 (UMRA), Public Law
104-4, establishes requirements for Federal agencies to assess the
effects of their regulatory actions on State, local, and tribal
governments and the private sector. Under section 202 of the UMRA, EPA
generally must prepare a written statement, including a cost-benefit
analysis, for proposed and final rules with "Federal mandates" that may
result in expenditures by State, local, and tribal governments, in the
aggregate, or to the private sector, of \$100 million or more in any 1
year. Before promulgating an EPA rule for which a written statement is
needed, section 205 of the UMRA generally requires EPA to identify and
consider a reasonable number of regulatory alternatives and adopt the
least costly, most cost-effective, or least burdensome alternative that
achieves the objectives of the rule. The provisions of section 205 do
not apply when they are inconsistent with applicable law. Moreover,
section 205 allows EPA to adopt an alternative other than the least
costly, most cost-effective, or least burdensome alternative if the
Administrator publishes with the final rule an explanation why that
alternative was not adopted. Before EPA establishes any regulatory
requirements that may significantly or uniquely affect small
governments, including tribal governments, it must have developed under
section 203 of the UMRA a small government agency plan. The plan must
provide for notifying potentially affected small governments, enabling
officials of affected small governments to have meaningful and timely
input in the development of EPA regulatory proposals with significant
Federal intergovernmental mandates, and informing, educating, and
advising small governments on compliance with the regulatory
requirements.

The EPA has determined that the proposed amendments do not contain a
Federal mandate that may result in expenditures of \$100 million or more
for State, local, and tribal governments, in the aggregate, or to the
private sector in any 1 year. As discussed earlier in this preamble,
these amendments result in nationwide net savings to the private sector.
Thus, the proposed rule is not subject to the requirements of sections
202 and 205 of the UMRA. In addition, the proposed amendments do not
significantly or uniquely affect small governments. The proposed
amendments contain no requirements that apply to such governments, and
impose no obligations upon them. The proposed rule is not subject to
section 203 of the UMRA.

E. [Executive Order 13132: Federalism]{.underline}

Executive Order 13132, entitled Federalism (64 FR 43255, August 10,
1999), requires EPA to develop an accountable process to ensure
"meaningful and timely input by State and local officials in the
development of regulatory policies that have federalism implications."
"Policies that have federalism implications" is defined in the Executive
Order to include regulations that have "substantial direct effects on
the States, on the relationship between the national government and the
States, or on the distribution of power and responsibilities among the
various levels of government."

The proposed amendments do not have federalism implications. They would
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. These proposed amendments add
control and performance demonstration requirements. They do not modify
existing responsibilities or create new responsibilities among EPA
Regional offices, States, or local enforcement agencies. Thus, Executive
Order 13132 does not apply to the proposed amendments.

In the spirit of Executive Order 13132, and consistent with EPA policy
to promote communications between EPA and State and local governments,
EPA specifically solicits comments on these proposed amendments from
State and local officials.

F. [Executive Order 13175: Consultation and Coordination with Indian
Tribal Governments]{.underline}

Executive Order 13175, entitled Consultation and Coordination with
Indian Tribal Governments (65 FR 67249, November 9, 2000), requires EPA
to develop an accountable process to ensure "meaningful and timely input
by tribal officials in the development of regulatory policies that have
tribal implications." The proposed amendments do not have tribal
implications, as specified in Executive Order 13175. They would not have
substantial direct effects on tribal governments, on the relationship
between the Federal government and Indian tribes, or on the distribution
of power and responsibilities between the Federal government and Indian
tribes, as specified in Executive Order 13175. The proposed amendments
impose no requirements on tribal governments. Thus, Executive Order
13175 does not apply to the proposed amendments.

EPA specifically solicits additional comment on these proposed
amendments from tribal officials.

G. [Executive Order 13045: Protection of Children from Environmental
Health Risks]{.underline} [and Safety Risks]{.underline}

Executive Order 13045, Protection of Children from Environmental Health
Risks and Safety Risks (62 FR 19885, April 23, 1997), applies to any
rule that: (1) is determined to be "economically significant," as
defined under Executive Order 12866, and (2) concerns an environmental
health or safety risk that EPA has reason to believe may have a
disproportionate effect on children. If the regulatory action meets both
criteria, EPA must evaluate the environmental health or safety effects
of the planned rule on children, and explain why the planned regulation
is preferable to other potentially effective and reasonably feasible
alternatives considered by the Agency.

The proposed rule is not subject to the Executive Order because they are
not economically significant as defined in Executive Order 12866, and
because the Agency does not have reason to believe the environmental
health or safety risks addressed by this action present a
disproportionate risk to children.

H. [Executive Order 13211: Actions That Significantly Affect Energy
Supply, Distribution, or Use]{.underline}

The proposed amendments are not a "significant energy action" as defined
in Executive Order 13211, Actions Concerning Regulations That
Significantly Affect Energy Supply, Distribution, or Use (66 FR 28355,
May 22, 2001) because they are not likely to have a significant adverse
effect on the supply, distribution, or use of energy. Further, we have
concluded that the proposed amendments are not likely to have any
adverse energy effects because they result in overall savings due to
product recovery.

I. [National Technology Transfer and]{.underline} [Advancement
Act]{.underline}

Section 12(d) of the National Technology Transfer and Advancement Act of
1995 (NTTAA) (Public Law No. 104-113, 12(d) (15 U.S.C. 272 note) directs
EPA to use voluntary consensus standards (VCS) in its regulatory
activities, unless to do so would be inconsistent with applicable law or
otherwise impractical. VCS are technical standards (e.g., materials
specifications, test methods, sampling procedures, and business
practices) that are developed or adopted by VCS bodies. The NTTAA
directs EPA to provide Congress, through OMB, explanations when the
Agency decides not use available and applicable VCS.

This proposed rule involves technical standards. EPA cites the following
methods in this rule: EPA Method 8260B, Volatile Organic Compounds by
Gas Chromatography/Mass Spectrometry (GC/MS), in Test Methods for
Evaluating Solid Waste, Physical/Chemical Methods (incorporated by
reference-see 40 CFR 63.14), for analysis of water samples taken from
cooling tower return lines; 40 CFR 61.355(c)(3) of the National Emission
Standards for Benzene Waste Operations for water sample collection; and
40 CFR part 63, appendix C, for the fraction biodegradation of benzene
in EBU. This proposed rule also cites the following VCS: Method 5210,
Biochemical Oxygen Demand (BOD), for measuring BOD~5~ (for 5-day BOD),
Method 5220, Chemical Oxygen Demand (COD), for measuring COD**,** and
Method 2540E, Fixed and Volatile Solids Ignited at 500 degrees C, for
measuring MLVSS concentration, all in Standard Methods for the
Examination of Water and Wastewater (incorporated by reference-see 40
CFR 63.14).

Consistent with the NTTAA, EPA conducted searches to identify VCS in
addition to the methods cited in this proposed rule. One VCS was found
that could potentially be applicable to this rule in lieu of Standard
Method 5220, Chemical Oxygen Demand (COD), for measuring COD. This
potential standard is ASTM D1252-06, Standard Test Methods for Chemical
Oxygen Demand (Dichromate Oxygen Demand) of Water. The EPA requests
comments on whether this standard should be reviewed for relevancy to
today's proposed rule. Based on the comments received, the EPA will
review this method for inclusion in the final rule. No VCS were found
for the other methods cited in this rule.

For the methods required or referenced by these proposed amendments, a
source may apply to EPA for permission to use alternative test methods
or alternative monitoring requirements in place of any required testing
methods, performance specifications, or procedures under 40 CFR 63.7(f)
and 40 CFR 63.8(f) of subpart A of the General Provisions. In general,
EPA welcomes comments on this aspect of the proposed amendments and,
specifically, invites the public to identify other
potentially-applicable VCS and to explain why such standards should be
used in this regulation.

J. [Executive Order 12898: Federal Actions to Address Environmental
Justice in Minority Populations and Low-Income Populations]{.underline}

Executive Order 12898 (59 FR 7629, February 16, 1994) establishes
Federal executive policy on environmental justice. Its main provision
directs Federal agencies, to the greatest extent practicable and
permitted by law, to make environmental justice part of their mission by
identifying and addressing, as appropriate, disproportionately high and
adverse human health or environmental effects of their programs,
policies, and activities on minority populations and low-income
populations in the United States.

EPA has determined that these proposed amendments will not have
disproportionately high and adverse human health or environmental
effects on minority or low-income populations because they increase the
level of environmental protection for all affected populations without
having any disproportionately

high and adverse human health or environmental effects on any

population, including any minority or low-income population.

These proposed amendments add new control requirements to established
national standards for petroleum refineries.

**List of Subjects** **in** **40 CFR Part 63**

Environmental protection, Air pollution control, Hazardous substances,
Incorporation by reference, Reporting and recordkeeping requirements.

Dated:

Stephen L. Johnson,

Administrator.

For the reasons stated in the preamble, title 40, chapter I, part 63 of
the Code of Federal Regulations is proposed to be amended as follows:

**Part 63\--\[AMENDED\]**

1\. The authority citation for part 63 continues to read as follows:

**Authority:** 42 U.S.C. 7401, [et]{.underline} [seq]{.underline}.

**Subpart A\--\[AMENDED\]**

**[\[Option 1 for §63.14\]]{.underline}**

2\. Section 63.14 is amended by adding paragraph (k)(1)(iv) to read as
follows:

**§63.14 Incorporations by reference.**

\* \* \* \* \*

\(k\) \* \* \*

\(1\) \* \* \*

\(iv\) Method 8260B, Volatile Organic Compounds by Gas
Chromatography/Mass Spectrometry (GC/MS), Revision 2 (and subsequent
revisions), dated December 1996 and in Update III, IBR approved for
§63.654(a)(1) and (b) of Subpart CC of this part.

\* \* \* \* \*

**[\[Option 2 for §63.14\]]{.underline}**

3\. Section 63.14 is amended by adding paragraphs (k)(1)(iv) and (l) to
read as follows:

**§63.14 Incorporations by reference.**

\* \* \* \* \*

\(k\) \* \* \*

\(1\) \* \* \*

\(iv\) Method 8260B, Volatile Organic Compounds by Gas
Chromatography/Mass Spectrometry (GC/MS), Revision 2 (and subsequent
revisions), dated December 1996 and in Update III, IBR approved for
§63.654(a)(1) and (b) of Subpart CC of this part.

\* \* \* \* \*

\(l\) The following material is available from the\
American Public Health Association, 1015 15th Street, NW, Washington, DC
20005 or at
[http://www.standardmethods.org](http://www.standardmethods.org/):

\(1\) The following methods as published in Standard Methods for the
Examination of Water and Wastewater, A.D. Eaton (ed.), [et]{.underline}
[al]{.underline}, 21st Edition (and subsequent editions), dated 2005:

\(i\) Method 2540E, Solids, dated 1997, IBR approved for §63.647(d)(5)
of Subpart CC of this part.

\(ii\) Method 5210, Biochemical Oxygen Demand (BOD), dated 2001, IBR
approved for §63.647(d)(6) of Subpart CC of this part.

\(iii\) Method 5220, Chemical Oxygen Demand (COD), dated 1997, IBR
approved for §63.647(d)(6) of Subpart CC of this part.

\(2\) \[Reserved\]

**Subpart CC\--\[AMENDED\]**

**[\[Option 1 for §63.640\]]{.underline}**

4\. Section 63.640 is amended by:

a\. Revising paragraph (a), introductory text;

b\. Revising paragraph (c), introductory text;

c\. Revising paragraphs (c)(6) and (7);

d\. Adding paragraph (c)(8);

e\. Revising paragraph (h), introductory text;

f\. Adding paragraph (h)(6);

g\. Revising the first sentence in paragraph (l), introductory text and
the first sentence in paragraph (l)(3), introductory text; and

h\. Adding paragraph (s).

**§63.640 Applicability and designation of affected source.**

\(a\) This subpart applies to petroleum refining process units and to
related emissions points that are specified in paragraphs (c)(5) through
(8) of this section that are located at a plant site and that meet the
criteria in paragraphs (a)(1) and (2) of this section:

\* \* \* \* \*

\(c\) For the purposes of this subpart, the affected source shall
comprise all emissions points, in combination, listed in paragraphs
(c)(1) through (8) of this section that are located at a single refinery
plant site.

\* \* \* \* \*

\(6\) All marine vessel loading operations located at a refinery meeting
the criteria in paragraph (a) of this section and the applicability
criteria of subpart Y, §63.560;

\(7\) All storage vessels and equipment leaks associated with a bulk
gasoline terminal or pipeline classified under Standard Industrial
Classification code 2911 located within a contiguous area and under
common control with a refinery meeting the criteria in paragraph (a) of
this section; and

\(8\) All cooling tower systems associated with petroleum refining
process units meeting the criteria in paragraph (a) of this section and
which meets the criteria in either paragraph (a)(8)(i) or (a)(8)(ii) of
this section:

\(i\) The cooling tower system provides non-contact cooling water to any
heat exchanger in Table 1 HAP service.

\(ii\) The cooling tower system receives cooling water from multiple
heat exchangers which serve different petroleum refinery process units
and any of the heat exchangers are in Tab1e 1 HAP service.

\* \* \* \* \*

\(h\) Except as provided in paragraphs (k), (l), or (m) of this section,
sources subject to this subpart are required to achieve compliance on or
before the dates specified in paragraphs (h)(1) through (6) of this
section.

\* \* \* \* \*

\(6\) Cooling tower systems that are part of an existing source shall be
in compliance with §63.654 no later than 3 years and 90 days after the
date of publication of the final amendments in the **Federal Register.**

\* \* \* \* \*

\(l\) If an additional petroleum refining process unit is added to a
plant site or if a miscellaneous process vent, storage vessel, gasoline
loading rack, marine tank vessel loading operation, or cooling tower
system that meets the criteria in paragraphs (c)(1) through (8) of this
section is added to an existing petroleum refinery or if another
deliberate operational process change creating an additional Group 1
emissions point(s) (as defined in §63.641) is made to an existing
petroleum refining process unit, and if the addition or process change
is not subject to the new source requirements as determined according to
paragraphs (i) or (j) of this section, the requirements in paragraphs
(l)(1) through (3) of this section shall apply. \* \* \*

\* \* \* \* \*

\(3\) The owner or operator of a petroleum refining process unit or of a
storage vessel, miscellaneous process vent, wastewater stream, gasoline
loading rack, marine tank vessel loading operation, or cooling tower
system meeting the criteria in paragraphs (c)(1) through (8) of this
section that is added to a plant site and is subject to the requirements
for existing sources shall comply with the reporting and recordkeeping
requirements that are applicable to existing sources including, but not
limited to, the reports listed in paragraphs (l)(3)(i) through (vii) of
this section. \* \* \*

\* \* \* \* \*

\(s\) Overlap of subpart CC with other regulations for cooling tower
systems. After the compliance date specified in paragraph (h) of this
section, the owner or operator of a cooling tower system that is also
subject to another subpart in this part (e.g., subpart F, YY, FFFF) is
exempt from the monitoring requirements in §63.654(a) through (d).

**[\[Option 2 for §63.640\]]{.underline}**

5\. Section 63.640 is amended by:

a\. Revising paragraph (a), introductory text;

b\. Revising paragraph (c), introductory text;

c\. Revising paragraphs (c)(6) and (7);

d\. Adding paragraph (c)(8);

e\. Revising paragraph (h), introductory text;

f\. Adding paragraphs (h)(6) through (8);

g\. Revising the first sentence in paragraph (l), introductory text and
the first sentence in paragraph (l)(3), introductory text; and

h\. Adding paragraph (s).

**§63.640 Applicability and designation of affected source.**

\(a\) This subpart applies to petroleum refining process units and to
related emissions points that are specified in paragraphs (c)(5) through
(8) of this section that are located at a plant site and that meet the
criteria in paragraphs (a)(1) and (2) of this section:

\* \* \* \* \*

\(c\) For the purposes of this subpart, the affected source shall
comprise all emissions points, in combination, listed in paragraphs
(c)(1) through (8) of this section that are located at a single refinery
plant site.

\* \* \* \* \*

\(6\) All marine vessel loading operations located at a refinery meeting
the criteria in paragraph (a) of this section and the applicability
criteria of subpart Y, §63.560;

\(7\) All storage vessels and equipment leaks associated with a bulk
gasoline terminal or pipeline classified under Standard Industrial
Classification code 2911 located within a contiguous area and under
common control with a refinery meeting the criteria in paragraph (a) of
this section; and

\(8\) All cooling tower systems associated with petroleum refining
process units meeting the criteria in paragraph (a) of the section and
which meets the criteria in either paragraph (a)(8)(i) or paragraph
(a)(8)(ii) of this section:

\(i\) The cooling tower system provides non-contact cooling water to any
heat exchanger in Table 1 HAP service.

\(ii\) The cooling tower system receives cooling water from multiple
heat exchangers which serve different petroleum refinery process units
and any of the heat exchangers are in Table 1 HAP service.

\* \* \* \* \*

\(h\) Except as provided in paragraphs (k), (l), or (m) of this section,
sources subject to this subpart are required to achieve compliance on or
before the dates specified in paragraphs (h)(1) through (8) of this
section.

\* \* \* \* \*

\(6\) Group 1 storage vessels that are part of an existing source shall
be in compliance with §63.646(c) and (e) no later than 3 years and 90
days after the date of publication of the final amendments in the
**Federal Register.**

\(7\) Group 1 wastewater streams that are part of an existing source
shall be in compliance with §63.647(d) no later than 3 years and 90 days
after the date of publication of the final amendments in the **Federal
Register.**

\(8\) Cooling tower systems that are part of an existing source shall be
in compliance with §63.654 no later than 3 years and 90 days after the
date of publication of the final amendments in the **Federal Register.**

\* \* \* \* \*

\(l\) If an additional petroleum refining process unit is added to a
plant site or if a miscellaneous process vent, storage vessel, gasoline
loading rack, marine tank vessel loading operation, or cooling tower
system that meets the criteria in paragraphs (c)(1) through (8) of this
section is added to an existing petroleum refinery or if another
deliberate operational process change creating an additional Group 1
emissions point(s) (as defined in §63.641) is made to an existing
petroleum refining process unit, and if the addition or process change
is not subject to the new source requirements as determined according to
paragraph (i) or paragraph (j) of this section, the requirements in
paragraphs (l)(1) through (3) of this section shall apply. \* \* \*

\* \* \* \* \*

\(3\) The owner or operator of a petroleum refining process unit or of a
storage vessel, miscellaneous process vent, wastewater stream, gasoline
loading rack, marine tank vessel loading operation, or cooling tower
system meeting the criteria in paragraphs (c)(1) through (8) of this
section that is added to a plant site and is subject to the requirements
for existing sources shall comply with the reporting and recordkeeping
requirements that are applicable to existing sources, including, but not
limited to, the reports listed in paragraphs (l)(3)(i) through (vii) of
this section. \* \* \*

\* \* \* \* \*

\(s\) Overlap of subpart CC with other regulations for cooling tower
systems. After the compliance date specified in paragraph (h) of this
section, the owner or operator of a cooling tower system that is also
subject to another subpart in this part (e.g., subpart F, YY, FFFF) is
exempt from the monitoring requirements in §63.654(a) through (d).

6\. Section 63.641 is amended by adding, in alphabetical order,
definitions for "Cooling tower system," "Cooling water return lines,"
and "Point of measurement for leak determination," to read as follows:

**§63.641 Definitions**

\* \* \* \* \*

[Cooling tower system]{.underline} means a closed loop recirculation
system or a once through system.

[Cooling water return lines]{.underline} means the main water trunk
lines at the inlet to the cooling tower before exposure to the
atmosphere.

\* \* \* \* \*

[Point of measurement for leak determination]{.underline} means any
location in the cooling water return line or lines prior to exposure of
the cooling water to the atmosphere.

\* \* \* \* \*

**[\[Option 2 for §63.646; Option 1 would not revise
§63.646\]]{.underline}**

7\. Section 63.646 is amended by revising paragraphs (c) and (e) to read
as follows:

**§63.646 Storage vessel provisions**.

\* \* \* \* \*

\(c\) On and after the compliance date specified in §63.640(h)(6), the
owner or operator of a storage vessel that is equipped with an external
floating roof and that is part of an existing source shall comply with
the requirements for slotted guide poles in §63.119(c)(2)(ix) and (x).
The following requirements do not apply to storage vessels at existing
sources subject to this subpart: §§63.119(b)(5); (b)(6); (c)(2)(i)
through (viii), (xi), and (xii); and (d)(2).

\* \* \* \* \*

\(e\) On and after the compliance date in §63.640(h)(6), when complying
with the inspection requirements of §63.120(b) of subpart G, owners and
operators of a storage vessel that is equipped with an external floating
roof and that is part of an existing source shall comply with the
provisions of §63.120(b)(10) and (b)(10)(i) for slotted guide poles as
described in paragraph (e)(1) and (2) of this section. The owner or
operator is not required to comply with the requirements for slotted
membranes.

\(1\) As part of the inspection required in §63.120(b)(10), the owner or
operator shall visually check the gasketed cover or flexible fabric
sleeve seal and gasketed float or other device for each slotted guide
pole.

\(2\) If the external floating roof has defects; the primary seal has
holes, tear, or other openings in the seal or the seal fabric; or the
secondary seal has holes, tears, or other openings in the seal or seal
fabric; or the gaskets (including a gasketed cover or gasketed float for
a slotted guide pole) no longer close off the liquid surface from the
atmosphere; or the flexible fabric sleeve seal for a slotted guide pole
has holes, tears, or other openings in the seal or seal fabric; or the
slotted membrane has more than 10 percent open area, the owner or
operator shall repair the items as necessary so that none of the
conditions specified in this paragraph exist before filling or refilling
the storage vessel with organic HAP.

\* \* \* \* \*

**[\[Option 2 for §63.647; Option 1 would not revise
§63.647\]]{.underline}**

8\. Section 63.647 is amended by adding paragraph (d) to read as
follows:

**§63.647 Wastewater provisions.**

\* \* \* \* \*

\(d\) On and after the compliance date specified in §63.640(h)(7), the
owner or operator of an enhanced biodegradation unit (EBU) that receives
a Group 1 wastewater stream from a petroleum refinery shall comply with
the requirements in paragraphs (d)(1) through (6) of this section. The
provisions in §61.348(b)(2)(ii)(B) for the recommended range for the
food-to-microorganism ratio, the mixed liquor suspended solids
concentration, and residence time do not apply, and the requirements in
§§61.348(b)(2)(i), 61.354(b)(2), and 61.355(k)(4)(i) for monitoring the
benzene concentration at the inlet to the EBU and maintaining it below
10 parts per million by weight (ppmw) do not apply.

\(1\) The fraction biodegraded of benzene in each EBU shall be 90
percent or greater.

\(2\) The mixed liquor volatile suspended solids (MLVSS) concentration
shall not fall below the operating limit established during the initial
performance test.

\(3\) The food-to-microorganism ratio shall not exceed the operating
limit established during the initial performance test.

\(i\) Food can be measured as either grams per liter (g/l) of 5-day
biological oxygen demand (BOD~5~) or g/l of chemical oxygen demand
(COD), but you must use the same measure used to develop your operating
limit.\
(ii) Determine the food-to-microorganism ratio operating limit using
Equation 1 of this section:

$\text{Food} - \text{to} - \text{microorganism}\ \text{ratio} = \ \frac{\text{BOD}_{5}\ x\ Q_{\text{in}}}{\left\lbrack \text{MLVSS} \right\rbrack\ x\ V_{\text{EBU}}}$
(Eq. 1)

Where:

BOD~5~ = 5-day biological oxygen demand or chemical oxygen

demand of EBU influent wastewater (g/l = kg/m^3^);

Q~in~ = Influent wastewater volumetric flow rate to the EBU

(m^3^/day);

\[MLVSS\] = Concentration of mixed liquor volatile suspended

solids (g/l = kg/m^3^); and

V~EBU~ = Average volume of wastewater in the EBU during normal

process operations (m^3^).

\(4\) The owner or operator shall conduct an initial performance test to
demonstrate compliance with the treatment efficiency standard of each
EBU using the following procedures:

\(i\) Determine the fraction biodegraded of benzene as determined
according to the procedures in appendix C to part 63 (Determination of
the Fraction Biodegraded (F~bio~) in a Biological Treatment Unit).

\(ii\) Use the multiple zone concentration method with separate "inlet"
zones for each inlet location containing an applicable benzene waste
stream. The inlet zone is defined as the depth of the EBU times the 100
square foot area surrounding each benzene wastewater inlet.

\(iii\) The remainder of the EBU may be modeled as a single zone or
multiple zones depending on the mixing zones present in the EBU as
described in appendix C to part 63.

\(iv\) The volume-weighted average MLVSS concentration used in the
multiple zone F~bio~ test must be used as the operating limit for MLVSS.
The volume-weighted average food-to-microorganism ratio used in the
multiple zone F~bio~ test must be used as the operating limit for the
food-to-microorganism ratio.

\(5\) Measure the MLVSS in the EBU no less frequently than once per week
using Method 2540 (incorporated by reference-see §63.14); and

\(6\) Measure the EBU influent biological oxygen demand (BOD) using
Method 5210 (incorporated by reference-see §63.14) or the COD MLVSS
using Method 5220 (incorporated by reference-see §63.14) in the EBU no
less frequently than once per week. Calculate the food-to-microorganism
ratio once a week using Equation 1 of this section and record the
results.

9\. Section 63.650 is amended by revising paragraph (a) to read as
follows.

**§63.650 Gasoline loading rack provisions.**

\(a\) Except as provided in paragraphs (b) through (c) of this section,
each owner or operator of a Group 1 gasoline loading rack classified
under Standard Industrial Classification code 2911 located within a
contiguous area and under common control with a petroleum refinery shall
comply with subpart R, §§63.421, 63.422(a) through (c), 63.425(a)
through (c), 63.425(e) through (h), 63.427(a) and (b), and 63.428(b),
(c), (g)(1), and (h)(1) through (3).

\* \* \* \* \*

10\. Sections 63.654 and 63.655 are redesignated as §§63.655 and 63.656.

11\. Revise existing references to §63.654 to §63.655. These references
to §63.654 appear in §63.640(b)(2), (e)(2)(iii), (f)(5), (k)(2)(ii),
(k)(2)(iii), (l) introductory text, (l)(3)(i), (l)(3)(ii); the
definition of "continuous record" in §63.641; §63.642(k)(1) and (l)(2);
§63.644(b) introductory text, (c)(1), (d), and (e); §63.645(h)(2);
§63.646(j) and (k); §63.652(e)(5), (f)(3), and (l)(1); §63.653(a)(7),
(b), (c), (d) introductory text, (d)(2)(vii), and (d)(2)(viii)(G);
§63.654(i)(1)(ii); entries for §§63.6(b)(5), 63.7(a)(2), 63.7(g),
63.7(h)(3), 63.8(c)(1)(ii), 63.8(c)(4), 63.8(f)(4)(i), 63.8(g),
63.9(b)(1)(i), 63.9(b)(4), 63.9(b)(5), , 63.10(d)(2), and 63.10(d)(5) of
Table 6 to subpart CC; and Footnotes d, f, and (g) of Table 10 to
subpart CC.

**[\[Option 1 for §63.654\]]{.underline}**

13\. Section 63.654 is added to read as follows:

**§63.654 Cooling tower systems.**

\(a\) On and after the compliance date specified in §63.650(h)(8), the
owner or operator of an existing source shall monitor each cooling tower
system subject to this subpart to detect and repair leaks of organic HAP
into the cooling water. The owner or operator may elect to monitor the
total organic HAP listed in Table 1 of this subpart on a quarterly basis
according to the requirements in paragraphs (a)(1) of this section or
monitor chemical usage or other surrogates according to the requirements
in paragraph (a)(2) of this section.

\(1\) The owner or operator shall conduct quarterly monitoring of total
organic HAP listed in Table 1 of this subpart according to the methods
and procedures in paragraphs (a)(1)(i) through (iii) of this section.

\(i\) Collect a water sample from each cooler water return line(s) prior
to air stripping or exposure to air. You must collect each sample using
the sampling procedures in §61.355(c)(3) of the National Emission
Standard for Benzene Waste Operations.

\(ii\) Analyze each sample using EPA Method 8260B (incorporated by
reference---see §63.14). Determine the total organic HAP concentration
as the sum of the individual HAP concentrations of the HAP listed in
Table 1 of this subpart.

\(iii\) If the total organic HAP concentration exceeds 1 part per
million by weight (ppmw), a leak is detected.

\(2\) The owner or operator shall monitor chlorine or bromine usage at
least once each day, free chlorine at least twice each day, oxidation
reduction potential (ORP) at least six times per day, hydrocarbons
(using an online analyzer) at least twice each day, or volatile organic
compounds (VOC) El Paso at least once each month according to the
procedures in paragraphs (a)(2)(i) through (iii).

\(i\) Conduct an initial analysis of the cooling water using EPA Method
8260B (incorporated by reference---see §63.14) to demonstrate that the
total organic HAP concentration is less than 1 ppmw.

\(ii\) Establish operating limits for the parameters to be monitored.
You must identify the parameters to be monitored and the established
operating limits in your Notification of Compliance Status and written
monitoring plan.

\(iii\) If the monitored operating parameter exceeds the operating
limit, you must sample the cooling water to determine the total organic
HAP concentration. If the total organic HAP concentration exceeds 1
ppmw, a leak is detected.

\(b\) On and after the compliance date specified in §63.650(h)(8), the
owner or operator of a new source shall monitor the concentration of HAP
from each cooling tower system subject to this subpart on a quarterly
basis to identify and repair any leak with a potential mass leak rate of
10 pounds per day (lb/day) or greater of any single HAP listed in Table
1 of this subpart or 100 lb/day or greater of total HAP listed in Table
1 of this subpart. A heat exchange system may consist of an entire heat
exchange system or a combination of heat exchangers such that, based on
the rate of cooling water and the sensitivity of the test method, a leak
of 10 lb/day or greater of any single HAP listed in Table 1 of this
subpart or 100 lb/day or greater of total HAP would be detected. The
owner or operator shall conduct the quarterly monitoring according to
the methods and procedures in paragraphs (a)(1) through (4) of this
section.

\(1\) Collect a water sample from each cooler water return line(s) prior
to air stripping or exposure to air. You must collect each sample using
the sampling procedures in §61.355(c)(3) of the National Emission
Standard for Benzene Waste Operations.

\(2\) Analyze each sample using EPA Method 8260B (incorporated by
reference---see §63.14). Determine the total HAP concentration as the
sum of the individual HAP concentrations of the HAP listed in Table 1 of
this subpart.

\(3\) Calculate and record the potential mass leak rate using Equation 1
of this section:

![](media/image1.wmf){width="1.3611111111111112in" height="0.25in"} (Eq.
1)

Where:

L = Potential mass leak rate of HAP (lb/day);

0.012 = Constant for unit conversion (lb/gallon ×

minutes/day × part per million parts);

C~HAP~ = Concentration of individual or total organic HAP in

the cooling tower water prior to exposure to the air

(ppmw); and

Q~CT~ = Volumetric flow rate of cooling water to the cooling

tower (gallons per minute).

\(4\) If the results of Equation 1 of this section indicate a leak with
a mass leak rate of 10 lb/day of any single HAP or 100 lb/day of total
HAP per day or greater, a leak is detected.

\(c\) If a leak is detected, the owner or operator must identify the
source of the leak as soon as practicable, but no later than 30 days
after receiving the sampling results that indicate the presence of a
leak.

\(d\) Except for a delay allowed under paragraph (e) of this section,
the owner or operator must repair any leak as soon as practicable, but
no later 30 days after identifying the source of leak. Repairs may
include:

\(1\) Physical repairs to the leaking heat exchanger;

\(2\) Blocking the leaking tube within the heat exchanger;

\(3\) Changing the pressure so that water flows into the process fluid;
or

\(4\) Replacing the heat exchanger.

\(e\) The owner or operator may delay the repair of a leak if the
conditions in paragraph (e)(1) or paragraph (e)(2) of this section are
met.

\(1\) Repairing the leak would require the process unit served by the
leaking heat exchanger to be shut down, and a shutdown for repair would
cause greater emissions than the potential emissions from the cooling
tower from the time the leaking exchanger was first identified and the
next planned shutdown.

\(i\) The facility must use the startup and shutdown emissions estimates
in the cooling tower monitoring plan required by paragraph (f) of this
section for the estimate of total organic HAP emissions for the process
unit serviced by the leaking heat exchanger.

\(ii\) The owner or operator must conduct monthly monitoring of the
total organic HAP concentration using EPA Method 8260B (incorporated by
reference---see §63.14).

\(iii\) The owner or operator shall recalculate the potential air
emissions from the cooling tower using the new sampling results and the
time period between the most recent sampling results and the next
planned shutdown. If the potential air emissions from the cooling tower
exceed the startup and shutdown emission estimates for any month, the
owner or operator must repair the heat exchanger within 30 days of
receiving the sampling results that voided the delay of repair; or

\(2\) The necessary parts are not reasonably available, in which case
the owner or operator must complete the repair as soon as practicable
upon receiving the necessary parts, but no later than 120 days after
identifying the leaking exchanger. The owner or operator can not further
delay the repair when a sampling result voids the delay of repair under
paragraph (e)(1)(iii) of this section.

\(f\) The owner or operator shall prepare, implement, and maintain
onsite at all times a cooling tower monitoring plan that includes the
information specified in paragraphs (f)(1) through (11) of this section.

\(1\) Identification of all cooling tower systems at the facility;

\(2\) Identification of the cooling tower systems subject to this
subpart;

\(3\) Identification of the cooling tower systems receiving cooling
water from a heat exchanger that are exempt from this subpart according
to §63.640(s);

\(4\) Identification of the heat exchanger(s) and process unit(s)
serviced by each cooling tower system that is subject to this subpart;

\(5\) The HAP concentration of the process fluids in each heat exchanger
serviced by a cooling tower system subject to this subpart;

\(6\) The surrogate parameters to be monitored, the monitoring
frequency, and parameter operating limits for each cooling tower system
subject to this subpart;

\(7\) The methods used to identify the leaking heat exchanger once a
leak is detected;

\(8\) Standard repair procedures that reduce emissions from leaks;

\(9\) Procedures for reporting leaks into the cooling water system;

\(10\) List of critical spare parts that must be maintained in
inventory;

\(11\) Engineering estimates of startup and shutdown organic HAP
emissions for each process unit serviced by a cooling tower subject to
this subpart.

**[\[Option 2 for §63.654\]]{.underline}**

14\. Section 63.654 is added to read as follows:

**§63.654 Cooling tower systems.**

\(a\) On and after the compliance date specified in §63.650(h)(8), the
owner or operator of a new or existing source shall monitor the
concentration of HAP from each cooling tower system subject to this
subpart on a monthly basis to identify and repair any leak with a
potential mass leak rate of 10 pounds per day (lb/day) or greater of any
single HAP listed in Table 1 of this subpart or 100 lb/day or greater of
total HAP listed in Table 1 of this subpart. A heat exchange system may
consist of an entire heat exchange system or a combination of heat
exchangers such that, based on the rate of cooling water and the
sensitivity of the test method, a leak of 10 lb/day or greater of any
single HAP listed in Table 1 of this subpart or 100 lb/day or greater of
total HAP would be detected. The owner or operator shall conduct the
monthly monitoring according to the methods and procedures in paragraphs
(a)(1) through (3) of this section.

\(1\) Collect a water sample from each cooler water return line(s) prior
to air stripping or exposure to air. You must collect each sample using
the sampling procedures in §61.355(c)(3) of the National Emission
Standard for Benzene Waste Operations.

\(2\) Analyze each sample using EPA Method 8260B (incorporated by
reference---see §63.14). Determine the total organic HAP concentration
as the sum of the individual HAP concentrations of the HAP listed in
Table 1 of this subpart.

\(3\) Calculate and record the potential mass leak rate using Equation 1
of this section:

![](media/image2.wmf){width="1.3611111111111112in" height="0.25in"} (Eq.
1)

Where:

L = Potential mass leak rate of HAP (lb/day);

0.012 = Constant for unit conversion (lb/gallon × minutes/day × part per
million parts);

C~HAP~ = Concentration of individual or total organic HAP in the cooling
tower water prior to exposure to the air (ppmw); and

Q~CT~ = Volumetric flow rate of cooling water to the cooling tower
(gallons per minute).

\(b\) If the results of Equation 1 of this section indicate a leak with
a mass leak rate of 10 lb/day of any single HAP or 100 lb/day of total
HAP per day or greater, the owner or operator must identify the source
of the leak as soon as practicable, but no later than 30 days after
receiving the sampling results that indicate the presence of a leak.

\(c\) Except for a delay allowed under paragraph (d) of this section,
the owner or operator must repair any leak with a mass leak rate of 10
pounds of any single Table 1 HAP or 100 pounds of total Table 1 HAP per
day or greater as soon as practicable, but no later 30 days after
identifying the source of leak. Repairs may include:

\(1\) Physical repairs to the leaking heat exchanger;

\(2\) Blocking the leaking tube within the heat exchanger;

\(3\) Changing the pressure so that water flows into the process fluid;
or

\(4\) Replacing the heat exchanger.

\(d\) The owner or operator may delay the repair of a leak if the
conditions in paragraph (d)(1) or paragraph (d)(2) of this section are
met.

\(1\) Repairing the leak would require the process unit served by the
leaking heat exchanger to be shut down, and a shutdown for repair would
cause greater emissions than the potential emissions from the cooling
tower from the time the leaking exchanger was first identified and the
next planned shutdown.

\(i\) The facility must use the startup and shutdown emissions estimates
in the cooling tower monitoring plan required by paragraph (e) of this
section for the estimate of HAP emissions for the process unit serviced
by the leaking heat exchanger.

\(ii\) The owner or operator must continue monthly monitoring of HAP as
required by paragraph (a) of this section.

\(iii\) The owner or operator shall recalculate the potential air
emissions from the cooling tower using the new sampling results and the
time period between the most recent sampling results and the next
planned shutdown. If the potential air emissions from the cooling tower
exceed the startup and shutdown emission estimates for any month, the
owner or operator must repair the heat exchanger within 30 days of
receiving the sampling results that voided the delay of repair; or

\(2\) The necessary parts are not reasonably available, in which case
the owner or operator must complete the repair as soon as practicable
upon receiving the necessary parts, but no later than 120 days after
identifying the leaking exchanger. The owner or operator can not further
delay the repair when a sampling result voids the delay of repair under
paragraph (d)(1)(iii) of this section.

\(e\) The owner or operator shall prepare, implement, and maintain
onsite at all times a cooling tower monitoring plan that includes the
information specified in paragraphs (e)(1) through (10) of this section.

\(1\) Identification of all cooling tower systems at the facility;

\(2\) Identification of the cooling tower systems subject to this
subpart;

\(3\) Identification of the cooling tower systems receiving cooling
water from a heat exchanger that are exempt from this subpart according
to §63.640(s);

\(4\) Identification of the heat exchanger(s) and process unit(s)
serviced by each cooling tower system that is subject to this subpart;

\(5\) The HAP concentration of the process fluids in each heat exchanger
serviced by a cooling tower system subject to this subpart;

\(6\) The methods used to identify the leaking heat exchanger once a
leak is detected;

\(7\) Standard repair procedures that reduce emissions from leaks;

\(8\) Procedures for reporting leaks into the cooling water system;

\(9\) List of critical spare parts that must be maintained in inventory;

\(10\) Engineering estimates of startup and shutdown HAP emissions for
each process unit serviced by a cooling tower subject to this subpart.

**[\[Option 1 for §63.655\]]{.underline}**

15\. Newly redesignated §63.655 is amended by:

a\. Revising paragraph (f)(1), introductory text, and adding paragraph
(f)(1)(vi);

b\. Revising paragraph (g), introductory text and adding paragraph
(g)(9);

> c\. Redesignating existing paragraph (i)(4) as (i)(5); and

d\. Adding paragraph (i)(4).

**§63.655 Reporting and recordkeeping requirements.**

\* \* \* \* \*

\(f\) \* \* \*

\(1\) The Notification of Compliance Status report shall include the
information specified in paragraphs (f)(1)(i) through (vi) of this
section.

\* \* \* \* \*

\(vi\) For each cooling tower system, identification of the cooling
tower systems that are subject to the requirements of this subpart and
cooling tower systems that are exempt from the requirements of this
subpart.

\* \* \* \* \*

\(g\) The owner or operator of a source subject to this subpart shall
submit Periodic Reports no later than 60 days after the end of each
6-month period when any of the compliance exceptions specified in
paragraphs (g)(1) through (6) of this section or paragraph (g)(9) of
this section occur. The first 6-month period shall begin on the date the
Notification of Compliance Status report is required to be submitted. A
Periodic Report is not required if none of the compliance exceptions
identified in paragraph (g)(1) through (6) of this section or paragraph
(g)(9) of this section occurred during the 6-month period unless
emissions averaging is utilized. Quarterly reports must be submitted for
emission points included in emission averages, as provided in paragraph
(g)(8) of this section. An owner or operator may submit reports required
by other regulations in place of or as part of the Periodic Report
required by this paragraph if the reports contain the information
required by paragraphs (g)(1) through (9) of this section.

\* \* \* \* \*

\(9\) For cooling tower systems, Periodic Reports must include the
following information:

\(i\) A summary of the leak monitoring data, including the number of
leaks determined to be equal to or greater than 10 lbs/day of any one
HAP or 100 lb/day of total HAP;

\(ii\) If applicable, the date a leak was identified, the date the
source of the leak was identified, and the date of repair.

\(iii\) If applicable, a summary of the reason for delayed repair of any
leak and the date of repair.

\* \* \* \* \*

\(i\) \* \* \*

\(4\) The owner or operator of a cooling tower system subject to the
monitoring requirements in §63.654 shall comply with the recordkeeping
requirements in paragraphs (i)(4)(i) through (iii) of this section.

\(i\) HAP analytical results.

\(ii\) The date when a leak was identified by sampling results, the date
when the heat exchanger leak source was identified, and the date when
the leak source was repaired or taken out of service.

\(iii\) If a repair is delayed, the reason for the delay. If the daily
is based on startup and shutdown emissions, the initial and monthly
calculations of the potential cooling tower emissions and the date of
the next planned shutdown.

\* \* \* \* \*

**[\[Option 2 for §63.655\]]{.underline}**

16\. Newly redesignated §63.655 is amended by:

a\. Revising paragraph (f)(1) introductory text, revising paragraph
(f)(1)(i)(A)*(*[1]{.underline}*)*, and adding paragraphs (f)(1)(vi) and
(vii);

b\. Revising paragraphs (g) introductory text, (g)(1), and
(g)(3)(iii)(A) and adding paragraphs (g)(9) and (g)(10);

> c\. Redesignating existing paragraph (i)(4) as (i)(5); and

d\. Adding paragraph (i)(4).

**§63.655 Reporting and recordkeeping requirements.**

\* \* \* \* \*

\(f\) \* \* \*

\(1\) The Notification of Compliance Status report shall include the
information specified in paragraphs (f)(1)(i) through (f)(1)(vi) of this
section.

\(i\) \* \* \*

\(A\) \* \* \*

*([1]{.underline})* For each Group 1 storage vessel complying with
§63.646 that is not included in an emissions average, the method of
compliance (i.e., internal floating roof, external floating roof, or
closed vent system and control device) and for each Group 1 storage
vessel that is equipped with an external floating roof and that is part
of an existing source, the method of compliance with the requirements
for slotted guidepoles (i.e., gasketed cover or sleeveless seal and
gasketed float or other device).

\* \* \* \* \*

\(vi\) For each cooling tower system, identification of the cooling
tower systems that are subject to the requirements of this subpart and
cooling tower systems that are exempt from the requirements of this
subpart.

\(vii\) For each EBU, identification of the operating limits for the
mixed liquor volatile suspended solids concentration and
food-to-microorganism ratio established during the performance test and
a full copy of the performance test report.

\(g\) The owner or operator of a source subject to this subpart shall
submit Periodic Reports no later than 60 days after the end of each
6-month period when any of the compliance exceptions specified in
paragraphs (g)(1) through (6) of this section or paragraph (g)(9) of
this section occur. The first 6-month period shall begin on the date the
Notification of Compliance Status report is required to be submitted. A
Periodic Report is not required if none of the compliance exceptions
identified in paragraph (g)(1) through (6) of this section or paragraph
(g)(9) of this section occurred during the 6-month period unless
emissions averaging is utilized. Quarterly reports must be submitted for
emission points included in emission averages, as provided in paragraph
(g)(8) of this section. An owner or operator may submit reports required
by other regulations in place of or as part of the Periodic Report
required by this paragraph if the reports contain the information
required by paragraphs (g)(1) through (9) of this section.

\(1\) For storage vessels, Periodic Reports shall include the
information specified for Periodic Reports in paragraphs (g)(2) through
(5) of this section except that information related to gaskets, slotted
membranes, and sleeve seals is not required for a storage vessel that is
part of an existing source and that is equipped with a fixed roof and an
internal floating roof or an external floating roof converted to an
internal floating roof. Information related to gaskets and sleeve seals
for slotted guide poles is required for a storage vessel that is part of
an existing source and that is equipped with an external floating roof.

\* \* \* \* \*

\(3\) \* \* \*

\(iii\) \* \* \*

\(A\) A failure is defined as any time in which the external floating
roof has defects; or the primary seal has holes or other openings in the
seal or the seal fabric; or the secondary seal has holes, tears, or
other openings in the seal or the seal fabric, or the gaskets (including
a gasketed cover or gasketed float for a slotted guide pole) no longer
closes off the liquid surface from the atmosphere; or a flexible fabric
sleeve seal for a slotted guide pole has holes or other openings or, for
a new source, the gaskets no longer close off the liquid surface from
the atmosphere; or, for a storage vessel that is part of a new source,
the slotted membrane has more than 10 percent open area.

\* \* \* \* \*

\(9\) For cooling tower systems, Periodic Reports must include the
following information:

\(i\) A summary of the leak monitoring data, including the number of
leaks determined to be equal to or greater than 10 lbs/day of any one
HAP or 100 lbs/day of total HAP;

\(ii\) If applicable, the date a leak was identified, the date the
source of the leak was identified, and the date of repair.

\(iii\) If applicable, a summary of the reason for delayed repair of any
leak and the date of repair.

\(10\) For EBU, the periodic report must clearly identify any excursion
from the operating limit for the concentration of mixed liquor volatile
suspended solids or the food-to-microorganism ratio established in the
initial performance test.

\* \* \* \* \*

\(i\) \* \* \*

\(4\) The owner or operator of a cooling tower system subject to the
monitoring requirements in §63.654 shall comply with the recordkeeping
requirements in paragraphs (i)(4)(i) through (iii) of this section.

\(i\) HAP analytical results.

\(ii\) The date when a leak was identified by sampling results, the date
when the heat exchanger leak source was identified, and the date when
the leak source was repaired or taken out of service.

\(iii\) If a repair is delayed, the reason for the delay. If the delay
is based on startup and shutdown emissions, the initial and monthly
calculations of the potential cooling tower emissions and the date of
the next planned shutdown.

\* \* \* \* \*

17\. Table 11 of the appendix to subpart CC of part 63 is added as
follows:

[Table 11\--Applicability of NESHAP General Provisions (40 CFR Part 63,
Subpart A) to Subpart CC]{.underline}

+--------------------------+-----------+-------------------------------+
| Citation                 | Applies   | Comment                       |
|                          |           |                               |
|                          | to        |                               |
|                          | Subpart   |                               |
|                          |           |                               |
|                          | CC        |                               |
+--------------------------+-----------+-------------------------------+
| 63.1(a)(1)-              | Yes       | General Applicability         |
|                          |           |                               |
| 63.1(a)(3)               |           |                               |
+--------------------------+-----------+-------------------------------+
| 63.1(a)(4)               | No        | This table specifies          |
|                          |           | applicability of General      |
|                          |           | Provisions to Subpart CC      |
+--------------------------+-----------+-------------------------------+
| 63.1(a)(5)               | No        | \[Reserved\]                  |
+--------------------------+-----------+-------------------------------+
| 63.1(a)(6)               | No        |                               |
+--------------------------+-----------+-------------------------------+
| 63.1(a)(7)-(9)           | No        | \[Reserved\]                  |
+--------------------------+-----------+-------------------------------+
| 63.1(a)(10)              | No        | Subpart CC specifies calendar |
|                          |           | or operating day              |
+--------------------------+-----------+-------------------------------+
| 63.1(a)(11)-             | Yes       |                               |
|                          |           |                               |
| 63.1(a)(12)              |           |                               |
+--------------------------+-----------+-------------------------------+
| 63.1(b)(1)               | No        | Initial Applicability         |
|                          |           | Determination                 |
|                          |           |                               |
|                          |           | Subpart CC specifies          |
|                          |           | applicability                 |
+--------------------------+-----------+-------------------------------+
| 63.1(b)(2)               | No        | \[Reserved\]                  |
+--------------------------+-----------+-------------------------------+
| 63.1(b)(3)               | No        |                               |
+--------------------------+-----------+-------------------------------+
| 63.1(c)(1)               | No        | Subpart CC specifies          |
|                          |           | requirements                  |
+--------------------------+-----------+-------------------------------+
| 63.1(c)(2)               | No        | Area sources are not subject  |
|                          |           | to subpart CC                 |
+--------------------------+-----------+-------------------------------+
| 63.1(c)(3)-(4)           | No        | \[Reserved\]                  |
+--------------------------+-----------+-------------------------------+
| 63.1(c)(5)               | Yes       | Except that notification      |
|                          |           | requirements in subpart CC    |
|                          |           | apply                         |
+--------------------------+-----------+-------------------------------+
| 63.1(d)                  | No        | \[Reserved\]                  |
+--------------------------+-----------+-------------------------------+
| 63.1(e)                  | Yes       | Applicability of Permit       |
|                          |           | Program                       |
+--------------------------+-----------+-------------------------------+
| 63.2                     | Yes       | Definitions                   |
|                          |           |                               |
|                          |           | \'63.641 specifies that if    |
|                          |           | the same term is defined in   |
|                          |           | subparts A and CC, it shall   |
|                          |           | have the meaning given in     |
|                          |           | subpart CC                    |
+--------------------------+-----------+-------------------------------+
| 63.3                     | Yes       | Units and Abbreviations       |
+--------------------------+-----------+-------------------------------+
| 63.4(a)(1)-(2)           | Yes       |                               |
+--------------------------+-----------+-------------------------------+
| 63.4(a)(4)-(5)           | Yes       | \[Reserved\]                  |
+--------------------------+-----------+-------------------------------+
| 63.4(b)-                 | Yes       | Circumvention/                |
|                          |           |                               |
| 63.4(c)                  |           | Fragmentation                 |
+--------------------------+-----------+-------------------------------+
| 63.5(a)(1)               | Yes       | Construction and              |
|                          |           | Reconstruction-Applicability  |
|                          |           |                               |
|                          |           | Replace term \"source\" and   |
|                          |           | \"stationary source\" in      |
|                          |           |                               |
|                          |           | \'63.5(a)(1) with \"affected  |
|                          |           | source\"                      |
+--------------------------+-----------+-------------------------------+
| 63.5(a)(2)               | Yes       |                               |
+--------------------------+-----------+-------------------------------+
| 63.5(b)(1)               | Yes       | Existing, New, Reconstructed  |
|                          |           | Sources -Requirements         |
+--------------------------+-----------+-------------------------------+
| 63.5(b)(2)               | No        | \[Reserved\]                  |
+--------------------------+-----------+-------------------------------+
| 63.5(b)(3)               | Yes       |                               |
+--------------------------+-----------+-------------------------------+
| 63.5(b)(4)               | Yes       |                               |
+--------------------------+-----------+-------------------------------+
| 63.5(b)(5)               | No        | \[Reserved\]                  |
+--------------------------+-----------+-------------------------------+
| 63.5(b)(6)               | Yes       |                               |
+--------------------------+-----------+-------------------------------+
| 63.5(c)                  | No        | \[Reserved\]                  |
+--------------------------+-----------+-------------------------------+
| 63.5(d)(1)(i)            | Yes       | Application for Approval of   |
|                          |           | Construction or               |
|                          |           | Reconstruction                |
|                          |           |                               |
|                          |           | Except subpart CC specifies   |
|                          |           | the application is submitted  |
|                          |           | as soon as practicable before |
|                          |           | startup but no later than 90  |
|                          |           | days (rather than 60) after   |
|                          |           | the promulgation date where   |
|                          |           | construction or               |
|                          |           | reconstruction had commenced  |
|                          |           | and initial startup had not   |
|                          |           | occurred before promulgation  |
+--------------------------+-----------+-------------------------------+
| 63.5(d)(1)(ii)           | Yes       | Except that emission          |
|                          |           | estimates specified in        |
|                          |           | \'63.5(d)(1)(ii)(H) are not   |
|                          |           | required                      |
+--------------------------+-----------+-------------------------------+
| 63.5(d)(1)(iii)          | Yes       |                               |
+--------------------------+-----------+-------------------------------+
| 63.5(d)(2)               | Yes       |                               |
+--------------------------+-----------+-------------------------------+
| 63.5(d)(3)               | Yes       |                               |
+--------------------------+-----------+-------------------------------+
| 63.5(d)(4)               | Yes       |                               |
+--------------------------+-----------+-------------------------------+
| 63.5(e)                  | Yes       | Approval of Construction or   |
|                          |           | Reconstruction                |
+--------------------------+-----------+-------------------------------+
| 63.5(f)(1)               | Yes       | Approval of Construction or   |
|                          |           | Reconstruction Based on State |
|                          |           | Review                        |
+--------------------------+-----------+-------------------------------+
| 63.5(f)(2)               | Yes       | Except that 60 days is        |
|                          |           | changed to 90 days and        |
|                          |           | cross-reference to (b)(2)     |
|                          |           | does not apply                |
+--------------------------+-----------+-------------------------------+
| 63.6(a)                  | Yes       | Compliance with Standards and |
|                          |           | Maintenance - Applicability   |
+--------------------------+-----------+-------------------------------+
| 63.6(b)(1)               | No        |                               |
+--------------------------+-----------+-------------------------------+
| 63.6(b)(2)               | Yes       |                               |
+--------------------------+-----------+-------------------------------+
| 63.6(b)(3)               | Yes       |                               |
+--------------------------+-----------+-------------------------------+
| 63.6(b)(4)               | No        |                               |
+--------------------------+-----------+-------------------------------+
| 63.6(b)(5)               | Yes       | Notification Requirements     |
+--------------------------+-----------+-------------------------------+
| 63.6(b)(6)               | No        | \[Reserved\]                  |
+--------------------------+-----------+-------------------------------+
| 63.6(b)(7)               | Yes       |                               |
+--------------------------+-----------+-------------------------------+
| 63.6(c)(1)               | Yes       |                               |
+--------------------------+-----------+-------------------------------+
| 63.6(c)(2)               | No        | Subpart CC specifies          |
|                          |           | compliance dates              |
+--------------------------+-----------+-------------------------------+
| 63.6(c)(3)-(4)           | No        | \[Reserved\]                  |
+--------------------------+-----------+-------------------------------+
| 63.6(c)(5)               | Yes       |                               |
+--------------------------+-----------+-------------------------------+
| 63.6(d)                  | No        | \[Reserved\]                  |
+--------------------------+-----------+-------------------------------+
| 63.6(e)(1)               | Yes       | Operation and Maintenance     |
|                          |           | Requirements                  |
+--------------------------+-----------+-------------------------------+
| 63.6(e)(2)               | No        | \[Reserved\]                  |
+--------------------------+-----------+-------------------------------+
| 63.6(e)(3)(i)            | Yes       | Startup, Shutdown, and        |
|                          |           | Malfunction Plan (SSM)        |
+--------------------------+-----------+-------------------------------+
| 63.6(e)(3)(ii)           | No        | \[Reserved\]                  |
+--------------------------+-----------+-------------------------------+
| 63.6(e)(3)(iii)          | Yes       |                               |
+--------------------------+-----------+-------------------------------+
| 63.6(e)(3)(iv)           | Yes       | Except that reports of        |
|                          |           | actions not consistent with   |
|                          |           | plan are not required within  |
|                          |           | 2 and 7 days of action but    |
|                          |           | rather must be included in    |
|                          |           | next periodic report          |
+--------------------------+-----------+-------------------------------+
| 63.6(e)(3)(v)-(ix)       | Yes       |                               |
+--------------------------+-----------+-------------------------------+
| 63.6(f)(1)               | Yes       | Compliance with Emission      |
|                          |           | Standards                     |
+--------------------------+-----------+-------------------------------+
| 63.6(f)(2)(i)            | Yes       |                               |
+--------------------------+-----------+-------------------------------+
| 63.6(f)(2)(ii)           | Yes       | Subpart CC specifies use of   |
|                          |           | monitoring data in            |
|                          |           | determining compliance        |
+--------------------------+-----------+-------------------------------+
| 63.6(f)(2)(iii)(A)-      | Yes       |                               |
|                          |           |                               |
| 63.6(f)(2)(iii)(C)       |           |                               |
+--------------------------+-----------+-------------------------------+
| 63.6(f)(2)(iii)(D)       | No        |                               |
+--------------------------+-----------+-------------------------------+
| 63.6(f)(2)(iv)-(v)       | Yes       |                               |
+--------------------------+-----------+-------------------------------+
| 63.6(f)(3)               | Yes       |                               |
+--------------------------+-----------+-------------------------------+
| 63.6(g)                  | Yes       | Alternative Standard          |
+--------------------------+-----------+-------------------------------+
| 63.6(h)                  | No        | Compliance with Opacity/VE    |
|                          |           | Standards Subpart CC does not |
|                          |           | include opacity/VE standards  |
+--------------------------+-----------+-------------------------------+
| 63.6(i)(1)-              | Yes       | Extension of Compliance       |
|                          |           |                               |
| 63.6(i)(14)              |           |                               |
+--------------------------+-----------+-------------------------------+
| 63.6(i)(15)              | No        | \[Reserved\]                  |
+--------------------------+-----------+-------------------------------+
| 63.6(i)(16)              | Yes       |                               |
+--------------------------+-----------+-------------------------------+
| 63.6(j)                  | Yes       | Exemption from Compliance     |
+--------------------------+-----------+-------------------------------+
| 63.7(a)(1)               | No        | Performance Test              |
|                          |           | Requirements - Applicability  |
|                          |           | and Dates                     |
|                          |           |                               |
|                          |           | Subpart CC specifies the      |
|                          |           | applicable test and           |
|                          |           | demonstration procedures      |
+--------------------------+-----------+-------------------------------+
| 63.7(a)(2)               | No        | Test results must be          |
|                          |           | submitted in the              |
|                          |           | notifi-cation of compliance   |
|                          |           | status report due 150 days    |
|                          |           | after the compliance date     |
+--------------------------+-----------+-------------------------------+
| 63.7(a)(3)               | Yes       |                               |
+--------------------------+-----------+-------------------------------+
| 63.7(b)                  | Yes       | Notifications                 |
|                          |           |                               |
|                          |           | Except Subpart CC specifies   |
|                          |           | notification at least 30 days |
|                          |           | prior to the scheduled test   |
|                          |           | date rather than 60 days      |
+--------------------------+-----------+-------------------------------+
| 63.7(c)                  | Yes       | Quality Assurance/Test Plan   |
+--------------------------+-----------+-------------------------------+
| 63.7(d)                  | Yes       | Testing Facilities            |
+--------------------------+-----------+-------------------------------+
| 63.7(e)(1)-              | Yes       | Conduct of Tests              |
|                          |           |                               |
| 63.7(e)(2)               |           |                               |
+--------------------------+-----------+-------------------------------+
| 63.7(e)(3)               | No        | Subpart CC specifies the      |
|                          |           | applicable methods and        |
|                          |           | procedures                    |
+--------------------------+-----------+-------------------------------+
| 63.7(e)(4)               | Yes       |                               |
+--------------------------+-----------+-------------------------------+
| 63.7(f)                  | Yes       | Alternative Test Method       |
|                          |           |                               |
|                          |           | Subpart CC specifies the      |
|                          |           | applicable methods and        |
|                          |           | provides alternatives         |
+--------------------------+-----------+-------------------------------+
| 63.7(g)                  | No        | Data Analysis, Recordkeeping, |
|                          |           | Reporting Subpart CC          |
|                          |           | specifies performance test    |
|                          |           | reports and requires          |
|                          |           | additional records for        |
|                          |           | continuous emission           |
|                          |           | monitoring systems            |
+--------------------------+-----------+-------------------------------+
| 63.7(h)(1)-              | Yes       | Waiver of Tests               |
|                          |           |                               |
| 63.7(h)(3)               |           |                               |
+--------------------------+-----------+-------------------------------+
| 63.7(h)(4)               | No        |                               |
+--------------------------+-----------+-------------------------------+
| 63.7(h)(5)               | Yes       |                               |
+--------------------------+-----------+-------------------------------+
| 63.8(a)                  | No        | Monitoring Requirements -     |
|                          |           |                               |
|                          |           | Applicability                 |
+--------------------------+-----------+-------------------------------+
| 63.8(b)(1)               | Yes       | Conduct of Monitoring         |
+--------------------------+-----------+-------------------------------+
| 63.8(b)(2)               | Yes       |                               |
+--------------------------+-----------+-------------------------------+
| 63.8(b)(3)               | Yes       |                               |
+--------------------------+-----------+-------------------------------+
| 63.8(c)(1)(i)            | Yes       | CMS Operation and Maintenance |
+--------------------------+-----------+-------------------------------+
| 63.8(c)(1)(ii)           | Yes       |                               |
+--------------------------+-----------+-------------------------------+
| 63.8(c)(1)(iii)          | Yes       |                               |
+--------------------------+-----------+-------------------------------+
| 63.8(c)(2)               | Yes       |                               |
+--------------------------+-----------+-------------------------------+
| 63.8(c)(3)               | Yes       | Except that operational       |
|                          |           | status verification includes  |
|                          |           | completion of manufacturer    |
|                          |           | written specifications or     |
|                          |           | installation operation, and   |
|                          |           | calibration of the system or  |
|                          |           | other written procedures that |
|                          |           | provide adequate assurance    |
|                          |           | that the equipment will       |
|                          |           | monitor accurately            |
+--------------------------+-----------+-------------------------------+
| 63.8(c)(4)               | No        | Monitoring frequency is       |
|                          |           | specified in subpart CC       |
+--------------------------+-----------+-------------------------------+
| 63.8(c)(5)-              | No        |                               |
|                          |           |                               |
| 63.8(c)(8)               |           |                               |
+--------------------------+-----------+-------------------------------+
| 63.8(d)                  | Yes       | Quality Control               |
+--------------------------+-----------+-------------------------------+
| 63.8(e)                  | Yes       | CMS Performance Evaluation    |
|                          |           |                               |
|                          |           | May be required by            |
|                          |           | Administrator                 |
+--------------------------+-----------+-------------------------------+
| 63.8(f)(1)               | Yes       | Alternative Monitoring Method |
+--------------------------+-----------+-------------------------------+
| 63.8(f)(2)               | Yes       |                               |
+--------------------------+-----------+-------------------------------+
| 63.8(f)(3)               | Yes       |                               |
+--------------------------+-----------+-------------------------------+
| 63.8(f)(4)(i)-(iv)       | Yes       |                               |
+--------------------------+-----------+-------------------------------+
| 63.8(f)(5)(i)-(iii)      | Yes       |                               |
+--------------------------+-----------+-------------------------------+
| 63.8(f)(6)               | No        |                               |
+--------------------------+-----------+-------------------------------+
| 63.8(g)                  | No        | Subpart CC specifies data     |
|                          |           | reduction for CMS             |
+--------------------------+-----------+-------------------------------+
| 63.9(a)                  | Yes       | Notification Requirements -   |
|                          |           | Applicability                 |
|                          |           |                               |
|                          |           | Duplicate notification of     |
|                          |           | compliance status report to   |
|                          |           | RA may be required            |
+--------------------------+-----------+-------------------------------+
| 63.9(b)(1)(i)            | Yes       | Initial Notifications         |
+--------------------------+-----------+-------------------------------+
| 63.9(b)(1)(ii)           | Yes       |                               |
+--------------------------+-----------+-------------------------------+
| 63.9(b)(1)(iii)          | Yes       |                               |
+--------------------------+-----------+-------------------------------+
| 63.9(b)(2)               | Yes       |                               |
+--------------------------+-----------+-------------------------------+
| 63.9(b)(3)               | No        | \[Reserved\]                  |
+--------------------------+-----------+-------------------------------+
| 63.9(b)(4)               | Yes       |                               |
+--------------------------+-----------+-------------------------------+
| 63.9(b)(5)               | Yes       |                               |
+--------------------------+-----------+-------------------------------+
| 63.9(c)                  | Yes       | Request for Compliance        |
|                          |           | Extension                     |
+--------------------------+-----------+-------------------------------+
| 63.9(d)                  | Yes       | New Source Notification for   |
|                          |           | Special Compliance            |
|                          |           | Requirements                  |
+--------------------------+-----------+-------------------------------+
| 63.9(e)                  | Yes       | Except notification is        |
|                          |           | required at least 30 days     |
|                          |           | before test                   |
+--------------------------+-----------+-------------------------------+
| 63.9(f)                  | Yes       | Notification of VE/Opacity    |
|                          |           | Test                          |
+--------------------------+-----------+-------------------------------+
| 63.9(g)                  | No        |                               |
+--------------------------+-----------+-------------------------------+
| 63.9(h)                  | Yes       |                               |
+--------------------------+-----------+-------------------------------+
| 63.9(i)                  | Yes       | Adjustment of Deadlines       |
+--------------------------+-----------+-------------------------------+
| 63.9(j)                  | No        | Change in Previous            |
|                          |           | Information                   |
+--------------------------+-----------+-------------------------------+
| 63.10(a)                 | Yes       | Recordkeeping/Reporting-      |
|                          |           |                               |
|                          |           | Applicability                 |
+--------------------------+-----------+-------------------------------+
| 63.10(b)(1)              | Yes       |                               |
+--------------------------+-----------+-------------------------------+
| 63.10(b)(2)(i)-(xiv)     | Yes       |                               |
+--------------------------+-----------+-------------------------------+
| 63.10(b)(3)              | Yes       |                               |
+--------------------------+-----------+-------------------------------+
| 63.10(c)                 | Yes       | Additional CMS Recordkeeping  |
+--------------------------+-----------+-------------------------------+
| 63.10(d)(1)              | No        | General Reporting             |
|                          |           | Requirements                  |
+--------------------------+-----------+-------------------------------+
| 63.10(d)(2)              | Yes       | Performance Test Results      |
+--------------------------+-----------+-------------------------------+
| 63.10(d)(3)              | Yes       |                               |
+--------------------------+-----------+-------------------------------+
| 63.10(d)(4)              | Yes       | Progress Reports              |
+--------------------------+-----------+-------------------------------+
| 63.10(d)(5)(i)           | Yes       | Startup, Shutdown, and        |
|                          |           | Malfunction Reports           |
|                          |           |                               |
|                          |           | Except that reports are not   |
|                          |           | required if actions are       |
|                          |           | consistent with SSM plan,     |
|                          |           | unless requested by           |
|                          |           | permitting authority          |
+--------------------------+-----------+-------------------------------+
| 63.10(d)(5)(ii)          | Yes       | Except that actions taken     |
|                          |           | during a startup, shut- down, |
|                          |           | or malfunction that are not   |
|                          |           | consistent with the plan do   |
|                          |           | not need to be reported       |
|                          |           | within 2 and 7 days of        |
|                          |           | commencing and completing the |
|                          |           | action, respectively, but     |
|                          |           | must be included in next      |
|                          |           | periodic report               |
+--------------------------+-----------+-------------------------------+
| 63.10(e)(1)              | Yes       | Additional CMS Reports        |
+--------------------------+-----------+-------------------------------+
| 63.10(e)(2)              | No        |                               |
+--------------------------+-----------+-------------------------------+
| 63.10(e)(3)              | Yes       | Excess Emissions/CMS          |
|                          |           | Performance Reports           |
+--------------------------+-----------+-------------------------------+
| 63.10(e)(4)              | No        |                               |
+--------------------------+-----------+-------------------------------+
| 63.10(f)                 | Yes       | Recordkeeping/Reporting       |
|                          |           | Waiver                        |
+--------------------------+-----------+-------------------------------+
| 63.11                    | Yes       | Control Device Requirements   |
|                          |           |                               |
|                          |           | Applicable to flares          |
+--------------------------+-----------+-------------------------------+
| 63.12                    | Yes       | State Authority and           |
|                          |           | Delegations                   |
+--------------------------+-----------+-------------------------------+
| 63.13                    | Yes       | Addresses                     |
+--------------------------+-----------+-------------------------------+
| 63.14                    | Yes       | Incorporation by Reference    |
+--------------------------+-----------+-------------------------------+
| 63.15                    | Yes       | Availability of Information/  |
|                          |           |                               |
|                          |           | Confidentiality               |
+--------------------------+-----------+-------------------------------+

[^1]: In the Benzene NESHAP decision, the Agency considered the same
    risk measures in the "acceptability" analysis as in the "margin of
    safety" analysis, stating: "In the ample margin decision, the Agency
    again considers all of the health risk and other health information
    considered in the first step. Beyond that information, additional
    factors relating to the appropriate level of control will also be
    considered, including costs and economic impacts of controls,
    technological feasibility, uncertainties, and any other relevant
    factors. Considering all of these factors, the Agency will establish
    the standard at a level that provides an ample margin of safety to
    protect the public health, as required by section 112."

[^2]: For an explanation of the corrections we accepted and the
    corrections we did not accept, see docket.

[^3]: Capacity includes owned or leased facilities as well as facilities
    under a processing agreement or an agreement such as an exchange
    agreement or a throughput. The total product to be delivered under
    the contract must be at least 90 percent refined by the successful
    bidder from either crude oil or bona fide feedstocks.