&EPA
United States
Environmental Protection
Agency
Office of Air Quality
Planning and Standards
Research Triangle Park, NO 27711
EPA-453/R-93-010
January 1993
Air
Benzene Waste Operations
NESHAP - Waiver Guidance
Document
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EPA-453/R-93-010
Benzene Waste
Operations NESHAP-
Waiver Guidance
Document
Emission Standards Division
U.S. Environmental Protection Agency
Region 5, Library (PL-12J)
77 West Jackson Boulevacd, 12th Floor
Chicago, IL 60604-3590
U.S. Environmental Protection Agency
Office of Air and Radiation
Office of Air Quality Planning and Standard*
R«March Triangle Park. North Carolina 27711
January 1993
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DISCLAIMER
This report has been reviewed by the Emission Standards Division of
the Office of Air Quality Planning and Standards, EPA. Mention of
trade names or commercial products is not intended to constitute
endorsement or recommendation for use. Copies of this report are
available through the Library Services Office (MD-35), U.S.
Environmental Protection Agency, Research Triangle Park NC 27711,
or from National Technical information Services, 5285 Port Royal
Road, Springfield VA 22161.
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CONTENTS
Chapter Page
List of Figures yi
List of Tables vii
1.0 Introduction 1-1
2.0 Overview of Waiver Policy 2-1
2.1 Authorization 2-1
2.2 Goals of Waiver Policy 2-1
2.3 Waiver Process Overview 2-4
2.4 Waiver Eligibility Criteria 2-5
2.5 Waiver Period vs. Length of Compliance
Schedule 2-6
3.0 Analysis and Evaluation of Compliance
Approaches 3-1
3.1 Introduction 3-1
3.2 Determining a Source's Waiver Mitigation
Goal 3-1
3.2.1 Use of TAB to Estimate Lost Benzene
Emissions 3-6
3.2.2 Estimates Based on Fraction Emitted . 3-8
3.3 Actions a Source May Take to Achieve
Mitigation Credit 3-10
3.3.1 Credits for Voluntary Actions Taken
as a Result of Other Programs .... 3-12
3.3.2 Categories of Mitigating Actions . . 3-14
3.3.3 Restrictions on Allowable
Mitigating Actions 3-14
3.3.4 Timing of Actions and Granting of
Credit 3-16
3.3.5 Valuation of Mitigation Actions . . . 3-19
3.3.6 Weighting of Emission Reductions
Other than Benzene 3-20
3.3.7 Calculation of Waiver Credit .... 3-21
3.3.8 Relationship of Waiver Actions to
Future Regulatory Requirements ... 3-21
4.0 Examples of Waiver Requests 4-1
4.1 What Are the Basic Compliance
Approaches? 4-1
4.1.1 Pipe the Wastes to a Unit for
Benzene Removal 4-1
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CONTENTS (continued)
Chapter
4.1.2 Control and Use the Existing
Wastewater Treatment System 4-2
4.1.3 Install a New, Hardpiped Segregated
Wastewater System 4-3
4.2 Examples of Mitigating Actions 4-3
4.3 Example Facilities 4-7
4.4 References 4-26
5.0 Waiver Review and Implementation 5-1
5.1 Waiver Application 5-1
5.2 Definition of Good Faith Efforts 5-2
5.3 Waiver Review 5-3
5.4 Title V Permits 5-4
5.5 Consent Decrees 5-5
5.6 Amending Waiver Agreements 5-6
5.7 Failure to Achieve Mitigating Benefits . . . 5-7
Appendices
A Procedures to Determine Benzene Emissions From
Waste Operations A-l
A.I Estimates Using Fraction Emitted A-l
A. 2 Alternative Procedures A-4
A. 3 References A-4
B Background Information for Reporting Wastes
Containing Benzene B-l
B.I What Types of Waste Streams Contain
Benzene B-l
B.I.I Process Wastewater and Other
.Process Wastes B-l
B.I.2 Tank Drawdown B-2
B.1.3 Wastes from Maintenance and
Cleaning B-2
B.I.4 Wastes from Waste Process
Turnaround B-3
B.1.5 Wastes from Waste Management
Activities B-3
B.2 What Are Common Mistakes in Reporting
Benzene Wastes? B-4
B.2.1 Determinations Are Made Prior to
Treatment B-4
B.2.2 Including Wastes That Have Less Than
10 Percent Water in the TAB . . . B-4
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CONTENTS (continued)
Appendices
B.2.3 Failure to Count Wastes Exempted
from Control as Part of TAB .... B-§
B.2.4 Failure to Include the Benzene in
All Phases of the Waste B-5
C List of Environmental Regulations Affecting
Those Facilities Under the Benzene Waste
Operations NESHAP C-l
D Policy for Granting Waivers of Compliance .... D-l
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LIST OF FIGURES
Number page
3-1 Lost Benzene Emission Reduction 3-3
4-1 Example - Facility 1: Compliance Schedule With
Benzene Reductions 4-9
4-2 Example - Facility 1: Mitigating Benzene
Reductions 4-12
4-3 Example - Facility 2: Compliance Schedule With
Benzene Reductions for 12/92 Rule 4-13
4-4 Example - Facility 2: Compliance Schedule With
Benzene Reductions for Alternative Standard . . . 4-15
4-5 Example - Facility 2: Mitigating Benzene
Reductions 4-17
4-6 Example - Facility 3: Compliance Schedule With
Benzene Reductions 4-19
4-7 Example - Facility 3: Mitigating Benzene
Reductions 4-21
4-8 Example - Facility 4: Compliance Schedule With
Benzene Reductions 4-23
4-9 Example - Facility 4: Mitigating Benzene
Reductions 4-25
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LIST OF TABLES
Number Page
3-1 Example Waste Data From 90-Day Report 3-7
4-1 Summary of Air Emission Points and Controls ... 4-5
A-l Estimates of Fraction of Benzene Emitted From
Waste Management Operations A-3
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1.0 INTRODUCTION
On March 7, 1990 (55 FR 8292), the EPA promulgated under
Section 112 of the Clean Air Act ("the Act"), national emission
standards for hazardous air pollutants (NESHAP) to control
emissions of benzene to ambient air from waste operations
(Subpart FF of 40 CFR Part 61). The NESHAP for benzene waste
operations applies to owners or operators of chemical
manufacturing plants, coke by-product plants, and petroleum
refineries. In addition, this subpart applies to owners and
operators of facilities at which waste management units are used
to treat, store, or dispose of waste generated by chemical
plants, coke by-product plants, or petroleum refineries.
The effective date for NESHAP promulgated under the Clean
Air Act (prior to the 1990 amendments) is the promulgation date,
and unless a waiver is granted by the Administrator, existing
facilities must be in compliance within 90 days of the effective
date. In the March 7, 1990, notice of final rulemaking for the
benzene waste operations NESHAP, the EPA noted that because of
the complexity of the controls required, and other reasons, most
facilities that must install controls would not be able to comply
with the standards within 90 days of the effective date.
Therefore, a compliance period of 2 years (to March 7, 1992) was
granted in the final standards to allow all sources to meet the
control requirements of Subpart FF. Two years is the maximum
waiver period that may be granted under 40 CFR 61.11 (a).
Relative to other NESHAP, Subpart FF is a complex rule that
contains complicated provisions for determining the rule's
applicability to facilities and individual waste streams within a
facility. Following promulgation of the rule, it became apparent
to the EPA that the rule was poorly understood by the affected
facilities. Questions and comments by the industry, consulting
firms, and local, State, and federal regulatory officials
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indicated widespread misunderstanding of many provisions of the .
rule. For example, a common point of confusion was how to
estimate total annual benzene quantity (TAB) for a facility, the
basic criterion that determines whether the control requirements
of the rule apply. Several facilities had incorrectly assumed
that controls were not required and as a result would not have
been in compliance by March 7, 1992. Based on these and other
considerations, the EPA concluded that action should be taken to
clarify the rule. Therefore, the EPA stayed the effectiveness of
Subpart FF (57 FR 8012, March 5, 1992) while clarifying
amendments to the rule were proposed (57 FR 8017, March 5, 1992)
and promulgated. The EPA agreed in a settlement resolving
litigation on the benzene waste operations NESHAP to take final
action on proposed amendments to Subpart FF by December 1, 1992
(See API v. EPA, No. 90-1238, Settlement Agreement, DC Circuit).
The amendments were signed by the Administrator on December 1,
1992, and were published in the Federal Register on January 7,
1993 (58 FR 3072).
Facilities will have until April 7, 1993, which is 90 days
from the effective date (i.e., the date of publication of the
final amendments to Subpart FF in the Federal Register), to
comply with all provisions of the amended rule (40 CFR 61.05(c)).
Any facility unable to comply with the amended rule in that
period would be eligible to apply for a waiver of compliance for
a maximum period of up to two years beyond the promulgation date
(January 7, 1995), following the procedures described in the
General Provisions to 40 CFR Part 61, Section 61.10.
As a result of comments received on the proposed
amendments, the EPA plans to propose an alternative compliance
option for Subpart FF. The alternative compliance option, if
promulgated, would allow facilities to perform a site-specific
risk assessment to determine if they meet the risk protection
goals of the benzene waste operations NESHAP. Owners or
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operators of affected facilities who are not meeting the
provisions of Subpart FF by April 1, 1993, and plan to use the
site-specific risk alternative compliance option, if it becomes
available, must obtain waivers of compliance. Facilities that
plan to use the alternative compliance option are not allowed
additional time beyond the waiver period. As prescribed in
Section 112 of the Act, once the maximum 2-year waiver period
expires on January 7, 1995, the source shall be in compliance
with Subpart FF regardless of whether the alternative compliance
option has been incorporated into Subpart FF.
This document outlines the goals and objectives of the
benzene waste operations NESHAP waiver policy and provides
guidance for preparing, reviewing, and evaluating waiver
requests. The guidance reflects the discussion of the waiver
policy in the preamble to the final amendments to Subpart FF (see
Appendix D).
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2.0 OVERVIEW OF WAIVER POLICY
2.1 Authorization
As stated in the final stay (57 FR 8012, March 5, 1992) and
final amendments to the benzene waste operations NESHAP that were
published on January 7, 1993, (40 CFR Part 61, Subpart FF,
pursuant to the authority of Section 112 of the Clean Air Act
prior to the Amendments of 1990), the EPA will consider granting
compliance waivers under Section 61.11 of the General Provisions
of 40 CFR Part 61 to facilities that are unable to comply with
the rule by the new compliance date (April 7, 1993). The EPA may
grant a waiver permitting a facility until January 7, 1995 (2
years after the effective date) to comply with the standards of
Subpart FF, if it is found that such a period is necessary for
the installation of controls and that steps will be taken during
the period of the waiver to protect public health (See Section
112(c)(1)(B)(ii) of the Clean Air Act as amended August 1977).
Under the revisions to the benzene waste operations NESHAP,
the waiver of compliance is not a general (or blanket) waiver
included specifically in the standards as was the case in the
original rule promulgated in March 1990. Under the amended rule,
each owner or operator is required to separately request a waiver
of compliance as directed in the general provisions of 40 CFR
Part 61. However, a two-year waiver of compliance is the maximum
that may be granted by the Administrator under Section 61.11.
The waiver period is intended to give a source adequate time tp
install necessary controls and thus comply with the rule. A
source seeking a waiver must provide the information required by
40 CFR Section 61.10(b).
2.2 Goals of Waiver Policy
The EPA is aware that some facilities will be unable to
comply with the amended Subpart FF rules by the new compliance
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date (April 7, 1993). This is in part a result of the long lead .
times needed to design and install the control systems necessary
to comply with the rule. There are also facilities that
mistakenly interpreted the rule in such a way as to conclude that
the control requirements did not apply to their facility; as a
result, development of an appropriate compliance plan was
delayed.
Another factor contributing to the inability of some
facilities to comply with the benzene waste operations NESHAP by
the new compliance date is the broad multimedia compliance
approach to environmental control being taken by some facilities.
These control strategies are designed to achieve integrated
compliance with multiple regulatory requirements. Many of the
integrated control approaches involve major design and
construction projects (such as the installation of new wastewater
collection and treatment systems) that require several years to
complete. The EPA recognizes that large facilities such as
petroleum refineries and chemical plants subject to Subpart FF
are also subject to a variety of other regulations addressing
releases to air, water, and land.
One goal of the waiver policy for Subpart FF is to
encourage facilities to develop comprehensive, integrated
strategies that 1) address the environmental control needs of all
production and waste management units at a plant, 2) stress the
most efficient and environmentally beneficial long-term
solutions, and 3) incorporate pollution prevention throughout the
facility's compliance scheme, in accordance with the national
policy expressed by the Pollution Prevention Act'of 1990.
As a matter of policy and practice, the EPA defines pollution
prevention consistent with the Pollution Prevention Act of 1990
as elaborated in the Agency's 1991 Pollution Prevention Strategy.
By granting compliance waivers, the EPA is in effect
allowing additional time for comprehensive multimedia compliance
programs to be completed. It should be emphasized that the
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intent of the waiver policy is not to provide an easy means for
facilities to delay compliance. Although facilities may
implement an integrated compliance approach that may require more
time than simply complying with the benzene waste operations
NESHAP alone, they must implement this approach as soon as
possible.
Another goal of the waiver policy is to obtain mitigating
environmental benefits to compensate for benzene emission
reductions lost as a result of delayed compliance. During the
period between the original compliance date of March 7, 1992, and
the end of the waiver period (i.e., the date the facility
actually comes into compliance with the NESHAP) the benzene
emitted from the facility's waste management operations will
exceed the quantity that would have been emitted had the facility
complied with the regulation on March 7, 1992. The EPA considers
it essential that facilities receiving waivers make up for the
excess emissions or "lost" benzene emissions reductions. Under
40 CFR Section 61.11(b), the Administrator may specify conditions
necessary to ensure protection of public health. Consistent with
this provision, Subpart FF (40 CFR 61.342(b)(2)) requires that
any waiver application include an enforceable plan for mitigating
the excess benzene air emissions resulting from extending the
compliance date. The excess benzene air emissions will be
mitigated by making additional emission reductions beyond those
required by the benzene waste operations NESHAP.
The final objective of the waiver policy is to provide
industry and reviewers some certainty about what entitles an
applicant to a waiver. Facilities that meet the requirements of
the waiver application as set forth in this document are assured
of receiving a waiver. The EPA, however, is aware that some
facilities unable to comply with the benzene waste NESHAP by
April 7, 1993 may not be able to fulfill all the stated
requirements (e.g., they may be unable to provide some of the
mitigating actions deemed acceptable in this document). In such
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cases, owners and operators are free to suggest other actions and
conditions not listed in this document as part of their waiver
application. Acceptance of such actions or conditions is subject
to the discretion of the reviewing authority (Regional office,
State, or other delegated agency).
2.3 Waiver Process Overview
Facilities have until April 7, 1993, to comply with the
amended rule. Any facility unable to comply with the rule as
amended within that period is eligible to apply for a waiver of
compliance for a maximum period of up to 2 years beyond the
effective date of the final amendments (i.e., January 7, 1995).
The requirements for applying for a waiver of compliance are
described in Section 6l.lO(b) of 40 CFR Part 61. For the benzene
waste operations NESHAP, these requirements will be implemented
as follows. The owner/operator of an affected facility must meet
the requirements of the Subpart on April 7, 1993, or have a
waiver application approved by the appropriate EPA Regional
Office (i.e., the EPA Region or State or other delegated
authority). As part of the waiver application, the
owner/operator must:
a) demonstrate the need for the waiver and explain why
compliance will be delayed,
b) submit a benzene waste operations NESHAP compliance
strategy and implementation schedule,
c) calculate a mitigation goal based on the benzene air
emissions reductions not achieved because of the
delayed compliance,
d) submit the information called for in the "90-day
report" required by Section 6l.357(a) of Subpart FF
that summarizes the regulatory status of the facility's
benzene waste streams,
e) specify and commit to a series of scheduled
environmental actions, not required under the benzene
waste operations NESHAP or other Federal, State, or
local regulations, that are designed to meet the
mitigation goal.
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Facility owner/operators awaiting the development of an
alternative compliance option can apply for a waiver; however,
they must submit a compliance strategy/schedule based on
compliance with the benzene waste NESHAP as amended on January 7,
1993. Owners or operators must calculate mitigation goals and
credits under the waiver policy based on a plan to comply with
Subpart FF, as amended on January 7, 1993, and not based on using
the alternative compliance option. If an additional compliance
option is promulgated, facility owners/operators may modify the
waiver and thereby reduce the mitigation goal, based from that
date forward on lost benzene emission reductions under the
alternative compliance option. However, the goal for mitigation
of lost benzene emission reductions, based on the amended rule,
that occurred prior to the effective date of the alternative
compliance option shall not be changed.
The plan for mitigating lost emissions will be evaluated
and assessed by the EPA Regional Office (including delegated
State and local agencies) in accordance with this guidance
document to determine their value as mitigation credit for
comparison to the mitigation goal. Based on their evaluation,
the EPA will decide whether a waiver is warranted, and if so,
will determine the period and conditions for the waiver.
Owners/operators that do not meet the conditions of the waiver or
that fail to achieve compliance by the end of the waiver period
will be subject to a consent decree or other enforcement action.
2-4 Waiver Eligibility Criteria
To be eligible for a waiver, an owner/operator of a source
must be able to demonstrate that it could not reasonably achieve
compliance by the compliance date (April 7, 1993).
The source owner/operator must also plan to achieve full
compliance with Subpart FF as expeditiously as possible,
considering their chosen compliance path and the uncertainty
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concerning development of the site-specific risk alternative
compliance option.
Lastly, the owner/operator of an affected facility must
sign an enforceable waiver agreement to achieve emission
reductions to compensate for the lost benzene emission reductions
resulting from delayed compliance with Subpart FF. Emission
reductions should be achieved from sources located at the
affected facility. To be counted or credited as mitigating
reductions, these mitigating environmental benefits must be
obtained during the time period between the old compliance date
(i.e., no earlier than March 7, 1992) and four years after the
new effective date (January 7, 1997).
2.5 Waiver Period vs. Length of Compliance Schedule
The EPA is aware that there will be occasions in which a
facility will require a compliance schedule that exceeds the
maximum waiver period allowed. For example, it may take an
owner/operator more than two years to implement a fully
integrated compliance approach and provide the required
mitigating environmental benefits.
The Administrator will not deny a waiver application solely
because an applicant does not project full compliance by
January 7, 1995, i.e., the maximum allowable waiver period. This
is a departure from past EPA policy where the Administrator would
not approve a waiver with a compliance schedule extending beyond
the waiver period. For this NESHAP, the Administrator may allow
compliance schedules to exceed two years (January 7, 1995) if the
owner/operator has committed to a compliance strategy that
demonstrates compliance is being achieved expeditiously and
includes achieving the required mitigating environmental
benefits. At the end of the two year waiver period, the facility
owner/operator could enter into a consent decree if compliance is
not achieved; this point is discussed further in Chapter 5.
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In no event will a waiver of compliance with Subpart FF
extend beyond January 7, 1995 (two years beyond the effective
date of the final rule); nor will a waiver be granted for a
period longer than the time reasonably needed to install the
control ecniipment or pollution prevention process changes that
the source intends to construct or implement. However/ the
waiver agreement may specify a time period to achieve mitigating
environmental benefits that lasts longer than the period needed
to comply with the benzene waste operations rule. The
administrative aspects related to this situation are discussed in
Chapter 5.
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3.0 ANALYSIS AND EVALUATION OF COMPLIANCE APPROACHES
3.1 Introduction
As discussed in Section 2.2 (Goals of Waiver Policy), the
EPA believes it is important to mitigate the environmental
effects of delayed compliance with the benzene waste operations
NESHAP. A source owner/operator requesting a waiver must propose
to achieve their mitigation goal (as discussed in Section 3.2 of
this guidance) by implementing mitigating actions. Section 3.3
of the guidance document defines acceptable mitigating actions
and discusses how the mitigating environmental actions will be
evaluated by the EPA for comparison to the mitigation goal.
3.2 Determining a Source*s Waiver Mitigation Goal
If a facility receives a waiver of compliance from
Subpart FF, there would be some quantity of "lost" benzene
emission reduction from waste operations during the period
between the original compliance date (March 7, 1992) and the end
of the waiver period. This section of the guidance document
describes how to estimate the quantity of benzene that will be
emitted during this period, i.e., the lost benzene emission
reduction.
As a surrogate to include the lost emission reduction
between the old and new compliance dates (March 1992 to April
1993), the lost benzene emission reduction during the waiver
period will be multiplied by 1.5 to yield the facility's waiver
mitigation goal. The factor of 1.5 is used only as an
approximation of the benzene emission reduction lost between the
compliance dates. Mitigation of the actual lost reduction
between the old and new compliance dates was also considered;
however, this approach would have introduced an inherent inequity
for facilities that request short-term waivers. (For example,
each facility that requested a waiver would have had to mitigate,
based on the April 1993 compliance date, the full 13 months of
emissions, whether the waiver request was for 2 months or for 2
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years.) Consequently/ the estimated benzene emission reduction
that is lost during the waiver period times 1.5 will serve as the
facility's waiver mitigation goal. In the waiver application,
the facility must propose sufficient mitigating actions to equal
the mitigation goal.
Figure 3-1 is a graphical representation of the lost
benzene emission reduction for an example facility, which is
represented by the dark shaded area. The graph represents a
worst case because it shows no benzene emission reduction during
the stay of the rule. Many facilities are expected to have
achieved some of the emission reduction required by the NESHAF
during this period.
The "lost" reduction in the figure is based on compliance
with the rule as amended on January 7, 1993. As previously
noted, an alternative compliance option based on site-specific
risk assessments may be proposed in early 1993. Facilities that
apply for waivers but anticipate meeting an alternative
compliance option based on site-specific risk should submit
waiver applications that reflect a two-phase compliance path.
The first phase would outline how compliance will be achieved
with a site-specific risk assessment-based compliance option. In
the waiver application, the applicant must demonstrate how, and
on what schedule, compliance under this option would be
expeditiously achieved. This phase of the compliance path would
not have to show installation of control equipment necessary for
compliance with §§61.343 through 61.349 of Subpart FF, if that
control equipment would not be required under a compliance option
based on a site-specific risk assessment alternative compliance
option.
The second phase of the waiver application's compliance
plan must document how the applicant will comply with §§61.343
through 61.349 of Subpart FF, as amended on January 7, 1993.
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This compliance path would then be implemented by the applicant
if an alternative compliance option based on site-specific risk
assessment is not promulgated. For planning purposes, facilities
should assume that the EPA will take final action on the
alternative compliance option by August 1993. An example of how
the lost benzene emission reduction would be calculated for the
alternative compliance option is given for Facility 2 in Section
4.3.
The basic information needed to assess the baseline of
benzene emissions from waste operations includes identification
of the individual waste streams that contain benzene, how much
benzene they contain/ and how these waste streams are managed.
An upper bound on benzene emissions is provided by the benzene
quantity in the waste (Qb)/ calculated from the quantity of waste
and the benzene concentration. The information on the individual
waste management units is used to estimate the fraction of the
benzene in the waste that is likely to be emitted (fe)- Benzene
emissions are then estimated as the product of Qb x fe for each
waste stream. More details on the estimates using the fraction
of benzene emitted are provided in Appendix A. Background
information on the waste streams that each source should report
and common mistakes that have been made in reporting wastes
streams with benzene are given in Appendix B..
Two approaches are provided for estimating the benzene
emission reductions lost during the waiver period. One approach
is simplified and is based on the determination of total annual
benzene-in-waste (TAB - the.quantity of benzene in wastes that
either contain more than 10 percent water or that subsequently
become part of a mixture that contains more than 10 percent
water). In this approach, the benzene emission reduction lost
(i.e., mass per unit time) during the waiver period is assumed to
equal the facility TAB plus any benzene quantities that are
excluded from the TAB calculation, such as averaging of process
turnaround wastes and ground water remediation wastes. This
approach is environmentally conservative and would tend to
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overestimate the actual emissions. The second approach is based
on estimates of benzene emissions from the various waste streams
for the different waste management units used at the facility.
Both approaches rely primarily on information that is gathered by
each facility for the 90-day report required under the rule.
The 90-day report identifies the waste streams that contain
benzene, waste quantity, benzene concentration, and the quantity
of benzene in the waste. This information should be used for
either approach.
The objective in presenting these two approaches to
estimating benzene emissions is to provide simple yet acceptable
means to calculate emissions (and lost emission reductions) from
sources regulated under the benzene waste operations NESHAP, and
the EPA urges applicants to use the methods specified in this
document. Applicants may estimate emissions using other means;
however, they do so at the risk that the alternative method
selected may not be approved by the EPA. Source testing is
generally discouraged as an emission estimating method for the
types of sources regulated under the benzene waste operations
NESHAP; this is because results of source tests generally reflect
emissions at a single point in time rather than over the long
term (i.e., annual average basis). Adequate rationale for using
alternative methods for estimating emissions must be provided in
the application for a waiver.
Mitigation goals and credits under the waiver policy must
be calculated based on a plan to achieve the emission levels
required by Subpart FF as amended on January 7, 1993. This basis
remains the same for facility owner/operators choosing to wait
for the development of a site-specific risk alternative
compliance option. If the alternative compliance option is
promulgated, owner/operators may modify their waiver
application/agreement to reduce the mitigation goal, based from
that date forward on lost benzene emission reductions under the
new compliance option.
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3.2.1. Use of TAB to Estimate Lost Benzene Emissions
The approach based on TAB is described using Table 3-1 to
illustrate the procedure. The example in the table is for a
facility with a TAB of 27 Mg/yr. Assume that the facility is
requesting a waiver of less than 2 years and expects the emission
controls needed for compliance with the rule to be in operation
at the end of the waiver period. The lost benzene emission
reduction during the waiver period (1.75 years from April 1993 to
January 1995) can be calculated using the facility's TAB. A
first approximation of the lost benzene emission reduction is 47
Mg (27 Mg/yr x 1.75 years). Using the 1.5 multiplier mentioned
earlier (to account for emissions during the stay of the rule)
yields a mitigation goal of 71 Mg (47 x 1.5).
This estimate assumes that all of the benzene in the TAB
potentially will be emitted and that the standard would control
100 percent of these emissions. In addition/ this example
assumes no substantive emission reduction is obtained until all
of the controls are in place, which occurs at the end of the
waiver period. (Some facilities are expected to achieve
significant emission reductions before the end of the waiver
period).
Emissions from wastes that at all times contain 10 percent
or less water (primary organic or "non-aqueous" wastes) should
also be included in the estimate of lost benzene emission
reductions. If a facility manages non-aqueous wastes containing
10 percent or less water in covered units (e.g., fixed roof
storage tanks), the emission factor in Appendix A can be used.
The resultant benzene emissions from these covered units would
generally be insignificant compared to the facility's emissions
from aqueous wastes. If the non-aqueous wastes are managed in
some other fashion, the emissions should be estimated using
methods applicable to that type of waste management operation.
A similar approach can be applied to a phased compliance
schedule. In the example in Table 3-1, the desalter water will
3-6
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3-7
-------
be controlled in 1.5 years, the product tank drawdown will be
controlled in 1.75 years, process wastewater will be controlled
in 1 year, and the slop oil tanks and sludges will be controlled
6 months into the waiver period. Based on the TAB and the
compliance schedule, the lost benzene emission reduction during
the waiver period can be approximated as 38 Mg (16 x 1.5 +5 x
1.75 + 4.8 x 1), which yields a mitigation goal of 57 Mg (38 x
1.5). The benzene in the slop oil and sludges has already been
included in the TAB shown in the table for the various water
streams; to include it in this calculation would be double
counting. The wastewater streams may contain multiple phases,
including an oil phase that eventually ends up as slop
oil and a sludge phase that may be removed in waste treatment
processes. However, the TAB is determined at the point of
generation before the waste treatment processes are used to
separate these phases.
3.2.2 Estimates Based on Fraction Emitted
This approach also uses the waste characterization data
provided in the 90-day report; however, emissions are estimated
based on the types of units that are used to manage the waste and
the emission control technologies serving these units. First,
each facility must determine the quantity and benzene
concentration of all of their waste streams. The facility must
also identify the types of waste management units that are used
for the treatment, storage, or disposal of the waste. The types
of waste management units are then matched with the units listed
in Appendix A to obtain an estimate of the fraction of the
benzene in the waste that is emitted. This procedure estimates
emissions by multiplying the waste quantity times the benzene
concentration times the fraction emitted. If multiple units are
used in series, the emission estimate for a subsequent unit must
account for the benzene emitted in previous units. This analysis
must also include emissions from wastes that contain 10 percent
or less water (e.g., organic wastes).
3-8
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For the example in Table 3-1, assume that the wastes are
currently managed in the wastewater collection and treatment
system that includes the collection system (i.e., process drainsf
lift stations, and junction boxes) and treatment tanks (i.e., an
open oil-water separator, equalization basin, and clarifier).
From Appendix A, the fraction emitted for the wastewater
treatment system (with an open oil-water separator) is 0.72. In
addition, assume that, in order to comply with the rule, a steam
stripper will be used to treat the wastes from the desalter, tank
drawdown, and process wastewater with an overall emission control
efficiency of 99 percent. Efficiencies for emission control
technologies range from 95 percent for simple add-on control
devices to 99 percent control by steam stripping. The annual
benzene emission reduction is estimated from the control
efficiency, fraction emitted, and benzene quantity for the wastes
streams that are controlled:
(benzene quantity) x (fraction emitted) x (efficiency/100)
(16 + 5 + 4.8) Mg/yr x (0.72) x (0.99) = 18 Mg/yr.
If the waiver period is 1.75 years and compliance is achieved
primarily at the end of the waiver period, the lost benzene
emission reduction would be 31.5 Mg and the mitigation goal would
be 47 Mg:
Waiver period: 1.75 years x 18 Mg/yr = 31.5 Mg
Mitigation goal: 31.5 Mg x 1.5 = 47 Mg
It is assumed that the organic wastes at this facility do not
make a significant contribution to this total and, therefore,
were not included in the overall estimate of lost benzene
emission reduction.
For the phased compliance approach, assume that the
controls will be installed on the same example schedule described
earlier. The lost benzene emission reduction is calculated for
each stream below:
3--9
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Desalter water: (16 x 0.72 x 0.99) Mg/yr x 1.5 yr - 17 Mg
Tank drawdown; (5.0 x 0.72 x 0.99) Mg/yr x 1.75 yr - 6.2 Mg
Other wastewater; (4.8 x 0.72 x 0.99) Mg/yr x 1.0 yr » 3.4 Mg
Total lost benzene emission reduction * 27 Mg
Mitigation goal; 27 Mg x 1.5 • 41 Mg.
This method of estimating the mitigation goal is more rigorous
than the previous method in which all the benzene in the facility
TAB is assumed to volatilize and no substantive emission
reduction is obtained (i.e, the entire TAB is emitted to the
atmosphere). In this example, emissions are estimated based on
the types of units used to manage the waste and the efficiencies
of the emission control technologies serving these units.
Additional details on the fractions emitted for specific waste
management units are given in Appendix A. Control efficiencies
are also given for different emission control approaches. In
some cases, exact control efficiencies may not be known and may
be too burdensome to estimate. For simplicity in estimating the
lost benzene emission reductions, an assumption of 100 percent
control (for only those waste streams that will be controlled)
will introduce very little error in the estimated benzene
emission reduction. The small error introduced by this
assumption would require the facility to mitigate a slightly
higher quantity of benzene emissions.
3.3 Actions a Source May Take to Achieve Mitigation Credit
Sources may implement any of a wide variety of actions for
the purpose of generating mitigation credits. In general,
mitigation actions must be either:
a. not required by Federal, State or local regulations at
the time agreement on the waiver conditions is reached,
or
3-10
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b. beyond control levels required by Federal, State or
local regulations at the time agreement on the waiver
conditions is reached/ or
c. in advance of future regulatory or legislative
requirements, but not after the compliance date of the
new requirements.
Permanent actions are preferred but temporary actions are
allowed; mitigating actions can cease when credits are equal to
debits (i.e., the mitigation goal).
Some facilities, in order to resolve or forestall
enforcement action, may have committed to a consent order or
decree entered by the court. As a condition of the decree, these
facilities may have agreed to install emission controls, or
otherwise reduce emissions. If such emission reductions are
beyond what is required by Federal, State, or local regulations
at the time agreement on the waiver conditions is reached, credit
will be given for emission reductions resulting from installation
of controls in advance of the schedule in the consent decree.
To illustrate the types and variety of rules affecting
benzene waste facilities, Appendix C lists the Federal air
environmental, regulations that affect petroleum refineries,
chemical plants, coke by-product plants, and waste treatment,
storage, and disposal facilities. This list is not all
inclusive; it is provided solely to assist reviewers and
applicants. The applicant remains responsible for certifying
that mitigating actions will be taken in advance of
Federal/State/local regulations, or exceed the requirements of
these regulations.
Credit towards a facility's mitigation goal must be
generated by actions taken at the source. Pooling and trading of
mitigating credits between facilities is not allowed, even if the
3-11
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facilities involved belong to the same owner/operator. If
sufficient on-site mitigation opportunities are lacking, the
reviewing authority may, at their discretion, consider off-site
actions. The applicant must demonstrate that the proposed off-
site emission reductions are real, quantifiable, enforceable, and
of direct benefit to the community surrounding/adjacent to the
facility.
3.3.1 Credits for Voluntary Actions Taken as a Result of
Other Programs
In general, reductions resulting from voluntary actions by
the facility and that are not required by a Federal, State, or
local regulation can be considered as mitigating actions; credit
for these actions will be granted beginning with the original
benzene waste operations NESHAP compliance date of March 1992.
Voluntary actions taken as a result of EPA or State initiatives
are allowable, but the actions must be documented and allowable
according to the specifics of this waiver guidance.
a) EPA's 33/50 Program: Sources can obtain mitigating
credit for actions taken under the EPA's 33/50 Toxics
Reduction Program as long as the reductions meet other
waiver criteria and can be documented according to the
requirements established under this waiver guidance.
The decision by sources to use their 33/50 actions as
mitigating credit will remain a voluntary one, but the
source owner/operator must make an enforceable
commitment to achieve these reductions to qualify for
mitigation under a Subpart FF compliance waiver. The
EPA will exert no pressure to require any 33/50 action
to become an enforceable commitment.
b) CAA Early Reductions Program; To the extent a source
makes reductions in accordance with the Air Toxics
Early Reduction's program authorized under subsection
(i)(5) of Section 112 of the 1990 Clean Air Act
3-12
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Amendments (CAAA), and to the extent those reductions
meet the other requirements of the waiver guidance,
credit will be given for the early reductions that are
initiated after March 7, 1992, up to the date of
proposal of the pertinent maximum achievable control
technology (MACT) standard authorized under Section
112(d) of the CAAA. No credit will be given for early
reductions after the pertinent MACT standard is
proposed.
c) Pollution Prevention Program; Mitigating credit can
also be generated through use of a pollution prevention
measure. For the purposes of this rule, the EPA is
referring to those activities defined as source
reduction measures in the Pollution Prevention Act.
The types of activities that would be considered
pollution prevention measures include technology
modifications, process and procedure modifications,
reformulation or redesign of products, and substitution
of raw materials. In each instance what defines them
as source reductions is that a lesser quantity of
pollution is produced prior to recycling, treatment, or
control of emissions for a given quantity of product.
A decrease in production alone does not qualify as
pollution prevention; therefore, emission reductions
resulting from shutdowns or downsizing of production or
waste management units will not be allowed as credit
for mitigating actions.
Pollution prevention measures will be allowed to
generate mitigation credit equal to the difference
between the emissions allowed by the standard as
applied to the previous process (after controls) and
the emissions from the modified process. This credit
will be allowed over the period the modified process is
in place and within the time frame specified for
accumulation of waiver credits in this document.
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Pollution prevention actions are the preferred means
within the environmental management hierarchy for
achieving mitigating benefits from the categories of
actions listed below. This is consistent with the
national policy established by Congress under the
Pollution Prevention Act of 1990. The hierarchy
established by the Act includes: 1) prevention or~
reduction, 2) out-of-process recycling, 3) treatment,
and 4) disposal or release.
3.3.2 Categories of Mitigating Actions
There are several categories of actions that will be
considered in evaluating waiver applications. Listed in order of
preference they are:
1) reductions in benzene air emissions from waste
operations not controlled by the NESHAP,
2) reductions in benzene air emissions from other sources,
3) control of emissions of hazardous air pollutant (HAP),
listed under §112 of CAA as amended in 1990, other than
benzene,
4) control of non-HAP volatile organic compound (VOC)
emissions, and
5) control of emissions of sulfur oxides (SOX) (maximum of
3 projects).
Further explanation and examples of these types of
mitigating actions are provided in Section 4.2 below ("Examples
of Mitigating Actions"). In addition, Section 4.3 discusses
examples of actions some sources could take to reduce air
pollutant emissions and the weighting factors applied to the
emission reductions achieved.
3.3.3 Restrictions on Allowable Mitigating Actions
Benzene emission reductions from waste operations can be
considered as mitigating actions if the reductions would not
otherwise be obtained under Subpart FF. For example, certain
wastes are exempt from the control requirements of the rule
3-14
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(e.g., wastes with a benzene concentration less than 10 ppmw).
If these wastes are treated for benzene removal or the units in
which they are managed are controlled for benzene emissions, the
resulting benzene emission reduction is an acceptable mitigating
action for the waiver application. However, no credit will be
given for additional treatment for benzene removal for those
waste streams that are required by the NESHAP to be controlled.
For example, if a facility chooses to steam strip a wastewater
stream to some level below 10 ppmw, credit will not be given for
the incremental control below 10 ppmw. The rationale for this
restriction is based on the fact that, in developing the rule and
its associated impacts, control or treatment of a large portion
of waste streams was assumed to result typically in benzene
concentrations in the waste well below 10 ppm (i.e., down to as
low as 0.5 ppm to meet the "toxicity characteristic" under the
Resource Conservation and Recovery Act (RCRA)). A 99.9-percent
benzene removal was assumed for steam stripping in the original
determination of the impacts of .the rule; this was in large part
a result of the high volatility of benzene in wastewater. The
EPA has concluded that, although current technology may allow
control of steam stripping effluent concentrations to just below
10 ppm, the incremental costs associated with this concomitant
control have not been shown to be significant. Therefore, these
benefits are attributed to implementation of the rule itself. In
addition, the incidental removal of pollutants other than benzene
(such as toluene, xylene, other volatiles) from an affected waste
stream that also occurs as a consequence of treating the waste
stream to remove benzene is not considered a mitigating action.
The control of these pollutants would be a direct consequence of
controls required by the benzene waste NESHAP, and as such, would
not represent additional emission reduction beyond that achieved
by the benzene waste operations NESHAP.
Another example involves the use of 95- or 98-percent
control devices on vented vapors that are required to be
controlled under the rule. The rule requires that these devices
achieve at least 95-percent control efficiency. However, a
3-15
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facility cannot credit the incremental control achieved by using
a 98-percent control device instead of using a device designed to
achieve 95-percent control. This restriction is based on the
fact that in many situations control devices designed and
operated to meet the requirements of the benzene waste rule would
in practice achieve greater than 95 percent benzene control;
therefore, this incremental emission control is directly
attributable to the benzene waste operations NESHAP. An example
of control device requirements in the NESHAP that, when met,
assure that the device achieves greater than 95 percent reduction
are the flare requirements in Section 61.349(a)(2)(iii). Flares
designed and operated to meet these conditions were found to
achieve at least a 98 percent destruction efficiency. Enclosed
combustion devices are also expected to achieve greater than 98
percent control and were considered in the basis for the
standards.
Mitigating actions affecting both benzene waste NESHAP-
subject waste streams and other waste streams would generate
mitigating credits only for emissions reductions from the non-
benzene waste NESHAP streams. Emission reductions from wastes
subject to the NESHAP would have occurred through compliance with
the NESHAP. With this approach, wastes not required to be
controlled under the NESHAP may be managed within the NESHAP
control system to obtain mitigation credit, which encourages
clustering (i.e., integrated approaches to treatment and
compliance).
3.3.4 Timing of Actions and Granting of Credit
A. When can actions start generating credit toward mitigation
goal?
Sources may credit any allowable mitigating action
implemented on March 7, 1992, or thereafter. Mitigating
credits begin to accumulate when the controls are in place
-------
and are operational or the actions have been carried out and
are thus in-effect. In addition, for voluntary reductions
of emissions that occur from participation in the EPA's
33/50 program, sources may credit the resulting emission
reductions that occur after March 7, 1992.
B. When do actions stop generating credit toward mitigation
goal?
The waiver policy encourages owner/operators to generate
credits toward the mitigation goal within the period of the
waiver requested. The EPA recognizes, however, that some
comprehensive compliance programs may not generate
sufficient mitigating credits within the proposed waiver
period. The EPA therefore will consider mitigating actions
occurring up to January 7, 1997 (a maximum of two years
following the end of the maximum allowed waiver period) for
the purpose of generating mitigating credits only.
C. Can credit be given for mitigating actions taken before a
Federal/State/local requirement is established?
There are two possible situations. One occurs when there is
an upcoming deadline for a regulatory or legislative
requirement that will occur sometime after the compliance
date for Subpart FF. In this case, credit can be given, but
only up until the compliance date of the regulatory or
legislative requirement.
The second situation occurs after the applicant and the EPA
agree on the waiver conditions. If a regulation is imposed
after the agreement that would affect a specific mitigating
action cited in the waiver agreement, the compliance date
for the new regulation will not cancel any credit agreed
upon between the EPA and the applicant, if the
owner/operator had no prior knowledge of the rulemaking.
3-17
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For facilities not participating in the Early Reductions
Program, mitigation credit for early compliance with MACT
standards will be allowed until the compliance date of the
rule. As noted earlier in 3.3.1(b), facilities
participating in the Early Reductions Program would receive
credit for early MACT compliance until the proposal of the
MACT standard.
D. If a facility is counting on promulgation of the alternative
compliance option, how will this affect the mitigation
credits required?
Facilities must plan on achieving compliance with Subpart
FF, even if they are waiting for the alternative compliance
option. Consequently, if a waiver is needed for compliance
with Subpart FF, facilities must compensate for the benzene
emissions lost due to delayed compliance with Subpart FF.
Mitigation goals and credits under the waiver policy must be
calculated based on a plan to comply with Subpart FF as
amended on January 7, 1993, and not based on the alternative
compliance option.
If the alternative compliance option is promulgated, and a
facility chooses this option as a route to compliance, the
facility must compensate for lost benzene emission
reductions until compliance with the alternative compliance
option is achieved. A facility may modify their waiver
application/agreement to reduce the mitigation goal based on
calculation of lost benzene emission reductions under a plan
to comply with the alternative compliance option. Lost
benzene emission reductions that occur prior to the
effective date of the alternative compliance option cannot
be changed.
3-18
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3.3.5 Valuation of Mitigation Actions
As discussed in Section 2.2 (Goals of Waiver Policy) of this
document, the EPA expects sources to achieve quantifiable
emissions reductions that mitigate the benzene emissions
reductions "lost" because of delayed compliance with the benzene
waste operations NESHAP. Sources must demonstrate that the
mitigating value calculated in accordance with the criteria
provided below, meets or exceeds the mitigation goal calculated
in Section 3.2.
a) The value of mitigating actions is calculated on the
basis of actual emissions reductions adjusted by a
weighting factor, discussed in Section 3.3.6 below.
b) Actual emissions reductions are to be expressed as the
mass of specific chemical constituents or group of
constituents. Emission reductions expressed as
reductions in total waste stream quantity will not be
accepted as part of the waiver application.
c) Mitigation credit will be given only for actual
reductions of air pollutants. Actual emission
reductions must account not only for the emission
reduction that occurs as a result of control actions
taken at a specific process or waste management unit,
but must also account for any increase in air emissions
resulting from these actions at subsequent units as the
pollutant is transferred from one unit to the next.
For example, suppression type controls such as
enclosures and covers can reduce emissions at the
enclosed/covered unit and thereby increase emissions at
the next downstream unit. Moving emissions from one
point to another will not be credited as an emission
reduction. In another example, a one (1) ton air
pollutant mitigation credit is earned for reduction of
benzene vapor in a gas stream through use of an
3-19
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absorption device such as a wet scrubber. This
technology transfers the benzene from one media, i.e.,
the gas stream/ to another media, i.e., the wastewater
stream. If the wastewater containing the benzene from
the gas stream is subsequently treated to destroy all
the benzene, then credit as a reduction in emissions
can be given for the entire one (1) ton. However, if
the benzene containing wastewater was subsequently
stored in an open surface impoundment or air stripped
following absorption then the mitigation credit should
account for the benzene emissions from this downstream
processing.
d) Source owner/operators should seek mitigating air
emission reductions in the order of priority cited in
Section 3.3.2.
In structuring the priority system of mitigating actions, it
is not the EPA's intent to require treatment of benzene waste
streams in a highly (i.e., unreasonably) costly manner or to
require that all benzene containing streams be treated before
credit is allowed for actions involving non-benzene emissions.
For example, conventional control technologies and work practices
applicable to waste management operation such as equipment leak
monitoring (leak detection and repair) programs for benzene
containing streams have been shown to be both technically
feasible and economically reasonable; however, the more stringent
control alternative applicable to the same waste streams, use of
leakless valves, has not been determined to be either technically
feasible (in all cases) or economically reasonable.
3.3.6 Weighting of Emission Reductions Other than Benzene
The weighting scheme used to calculate the value of
mitigating actions should not be considered a definitive risk
comparison between benzene NESHAP emission reductions and
reductions of other sources of air pollution. Nor is the
3-20
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mechanism outlined meant to produce a definitive statement that
the environmental risk resulting from delayed compliance is
absolutely mitigated.
The following weighting scheme has been selected for use in
evaluating mitigating environmental benefits. Any HAP, other
than benzene, listed pursuant to Section 112(b), Title III of the
Clean Air Act Amendments of 1990, will have a weighting factor of
1.1 (i.e., 1.1 Mg of other HAPs can be used to mitigate 1 Mg of
benzene). For VOCs that are non-HAPs and sulfur oxides, the
weighting factor is 2.2 (i.e., 2.2 Mg of VOCs or sulfur oxides
can be used to mitigate 1 Mg of benzene).
3.3.7 Calculation of Waiver Credit
An action's mitigating value is calculated as: (actual mass
of pollutant reduced) + (weighting factor for pollutant or group
of pollutants).
More detailed examples are explained in Section 4.
3.3.8 Relationship of Waiver Actions to Future Regulatory
Requirements
The EPA approval of a waiver application and/or successful
implementation of mitigating actions does not necessarily
constitute compliance with other current or future regulation
requirements, and should not be construed as indicating EPA
recognition of such compliance. The enforcement division will
ascertain compliance with respect to regulatory requirements.
3-21
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4.0 EXAMPLES OF WAIVER REQUESTS
The purpose of this section of the guidance document is to
present hypothetical scenarios of some of the waiver pathways
that are available. The examples illustrate the major approaches
that can be used to comply with the benzene waste NESHAP. In
addition, a variety of mitigating actions are incorporated into
the examples.
4.1 What Are the Basic Compliance Approaches?
The NESHAP provides a facility with several different
options to achieve compliance. This flexibility permits the
owner or operator to select a compliance approach that is best
suited to a particular facility, considering the number and
quantity of waste streams to be controlled, the plant layout,
cost of control, and other current or future environmental
regulations. A survey of the petroleum refining industry by the
American Petroleum Institute (API) indicated that different
plants planned to comply with the rule in different ways.
Although there are many possible combinations that can be used to
achieve compliance for any given source, the survey results
suggested that the compliance approaches could be divided into
three broad categories. Note that a specific plant, especially
one of the larger facilities, could choose to implement a
combination of the three general approaches described below.
4.1.1 Pipe the Wastes to a Unit for Benzene Removal
This approach involves collecting those waste streams that
must be controlled (e.g., wastewater with 10 ppm or more benzene)
and sending them to a steam, air, or fuel gas stripper to remove
the benzene from the water. The wastewaters would generally be
sent to a central location for stripping through hardpiping to
avoid the loss of benzene in the wastewater collection system.
The benzene removed from the waste is condensed and recovered,
collected by carbon adsorption, or added to the fuel gas system
and eventually destroyed by combustion.
4-1
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The advantage of this approach for some facilities is that
the existing wastewater collection and treatment system would not
have the controls that might otherwise be required if the streams
with 10 ppm or more benzene remained in the wastewater treatment
system. Steam stripping is an attractive option for facilities
that can isolate the streams that must be controlled and can pipe
them to a central location (or multiple locations for a large
plant) for treatment. This approach is less attractive for very
large plants, facilities with many different waste streams in
different locations that require treatment, and facilities that
plan to upgrade their wastewater collection and treatment system
for other reasons.
4.1.2 Control and Use the Existing Wastewater Treatment System
This approach would require air emission controls for
individual drain systems, junction boxes, and wastewater
treatment tanks in the existing system. Wastewater from the
various process units would be transported to wastewater
treatment as before; however, these units would be controlled for
air emissions. In a system that collects oily wastewater, most
of the benzene would be recovered at the oil-water separator with
the organic layer that is removed. Benzene that remains with the
water from the separator would likely be removed in controlled
units, such as a dissolved air flotation unit, or destroyed in an
enhanced biodegradation unit.
Controlling the existing wastewater treatment system may be
an attractive option for plants that have relatively modern
facilities, segregated storm water sewers, or collection systems
or tanks that are already controlled. For some of the older or
larger plants, the approach may not be attractive because
extensive repairs (or replacement) of parts of the system may be
required and extensive excavation or construction may be needed.
In addition, some plants may be planning to replace the existing
4-2
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system in the near future to avoid or to stop the contamination
of soil or groundwater by hazardous waste (e.g., water with over
0.5 ppm benzene).
4.1.3 Install a New, Hardpiped Segregated Wastewater System
Several facilities are considering the installation of new
wastewater collection and treatment systems. These systems would
have enclosed piping to transport the waste, which decreases the
potential for air emissions and leakage that may contaminate
groundwater. As further protection, the piping may be
constructed above ground which provides for timely leak detection
and repair. At some facilities, stormwater may be collected in a
separate system and managed in a manner different from that used
for the plant's wastewater. The control of benzene emissions
could be accomplished as described above for existing systems,
with most of the benzene recovered at the oil-water separator,
some benzene removed and captured from subsequent treatment
tanks, and some destroyed by biodegradation. With the enclosed
piping system, waste streams with high concentrations of benzene
could also be isolated for treatment in a steam stripper to
remove and recover the benzene.
This approach is both time consuming and expensive for some
of the larger facilities because of the extensive construction
work that must be performed at an operating plant. However, a
new wastewater collection system, perhaps with steam stripping
incorporated for certain wastes, may avoid the need for
corrective actions in the future under RCRA regulations. This
represents an integrated compliance approach (also known as
clustering) that offers benefits to the environment other than
the control of benzene air emissions alone.
4.2 Examples of Mitigating Actions
There are several different categories of actions that a
facility could perform to mitigate the lost benzene emission
reduction that results from extending the compliance date. These
classes, in order of their priority as mitigating actions for
: 4-3
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lost benzene emission reductions/ include 1) reductions in
benzene emissions from waste operations not obtained by the
NESHAP, 2) reductions in benzene emissions from other sources/ 3)
control of HAP emissions other than benzene/ 4) control of non-
HAP VOC emissions/ and 5) control of SOX emissions (limited
situations only). Additional details on the ground rules
associated with these mitigating actions are given in Section 3.
All of the categories of mitigating actions are associated
with the control of air emissions. Table 4-1 provides a summary
of typical air emission points and control techniques/
including sources associated with waste operations. These types
of sources are candidates for mitigating actions for control of
air emissions/ including benzene emissions as well as emissions
of other pollutants.
The first priority is to obtain additional benzene emission
reductions from waste operations/ if available. Benzene emission
reductions from waste operations can be considered as mitigating
actions if the reductions would not otherwise be obtained by the
NESHAP. For example/ certain wastes maybe exempt from the
control requirements of the rule (e.g./ wastes with a benzene
concentration less than 10 ppmw). If these wastes are treated
for benzene removal or the units in which they are managed are
controlled for benzene emissions/ the resulting benzene emission
reduction is an acceptable mitigating action. The removal of
other pollutants (such as toluene/ xylene/ other volatiles) from
the wastes that are not required to be controlled also can be
considered a mitigating action and could be credited as a result
of this same mitigating action.
However, few mitigating opportunities are expected to be
available in this category because most benzene waste streams are
addressed by Subpart FF. The types of waste streams that may be
available for additional emission control include 1) streams with
a low benzene concentration, and perhaps a small waste quantity,
4-4
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TABLE 4-1. SUMMRY OF AIR EMISSION POINTS AND CONTROLS
Baission point
Pn
res to determine emissions
Emission control*
• Tanks - fixed roof
• Tanks - floating roof
(1nternaI/externaI)
• Tanks - op«n top
(*.g., wastewater)
• Wastewater collection
(process drains,
junction boxes, sewer
lines)
• Equipment leaks
(pumps, valves, etc.)
• Transfer operations
(loading barges, tank
trucks, drums)
• Surface impoundments
• Land treatment
• Landfills
Process vents
(condensers, reactors,
separation columns)
Sludge dewatering
• Fixation
* Maintenance
(equipment cleanout,
draining)
• Spills
API storage tank equations; need concentration,
throughput; tank design factorsif2
API storage tank equations; need tank design
parameters; concentration and throughput^ 2,3
Documented emission models; naad site-
specific information on contents, operation*
Guidance, emission factors available^
EPA emission factors; knowledge of process
fluid; equipment count and leak survey2,6
EPA emission equations!^
Documented emission models; need site-
specific information on contents, operation*
Documented emission models; need site-
specific information on contents, operation*
Documented emission models; naad site-
specific information on contents, operation*
Measure concentration and flow rate?
Emission tests conducted8>9
EPA emission factors available:
refinements under development^
Adapt emission models; need quantity,
concentrat i on*
Bnission models available; need quantity,
concentration, frequency*
Vent to control device;
retrofit internal floating
roof
Secondary seals; gaskets;
enclose and vent to control
Cover and vent to contra I;
pretreat to remove benzene
Enclose; vent to control;
water seals; treat at point
of generation (steam strip)
Leak less equipment; leak
detection and repair
Submerged fill; vapor
balance; vent to control
Cover; vent to control;
pretreat (steam strip)
Pretreat to remove benzene
Pretreat to remove benzene;
enclose, vent to control
Vent to control device
Enclose, vent to control;
pretreat to remove benzene
Enclose, vent to control;
pretreat to remove benzene
Containment; enclosure;
Pretreat to remove volatil«s
Containment and cleanup;
improved housekeeping
4-5
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for which control is not cost effective, and 2) streams with
recoverable organics, large waste quantities, or other features
that make control cost effective (such as a waste stream from a
desalter with a concentration of less than 10 ppmw) .
Benzene emission reductions obtained from sources other than
waste operations at a facility represent the second priority and
can be used as mitigating actions. The mitigating action can
include controlling an emission source that would otherwise be
uncontrolled, or the action may obtain additional control of a
source that is already controlled. Many facilities may find that
few opportunities are available in this mitigation category
because emissions from these sources are addressed by other
NESHAP, New Source Performance Standards (NSPS), and Control
Technology Guidelines (CTG). Some possibilities are listed
below:
1. Control storage tanks not covered by a NESHAP, NSPS, or CTG,
or control beyond the requirements of the applicable rule.
• Vent a fixed roof tank to a control device or install
an internal floating roof,
• Vent tanks that have a floating roof to a control
device (not likely to be cost effective),
• Control tanks that contain less than pure benzene that
are not affected by Subpart Y, and
• Control tanks that fall below the tank size and vapor
pressure cutoffs of the NSPS for volatile organic
liquids.
2. Control emissions from equipment leaks not covered by a
NESHAP, NSPS, or CTG, or control beyond the requirements of
the applicable rule (for example, control to the level that
resulted from the regulatory negotiations for the hazardous
organic NESHAP).
3. Control process vents, which are generally not covered by
current rules (because the rules were developed under the
assumption that most vents are already controlled).
4. Control emissions from transfer operations, such as ships,
barges, and trucks that are not controlled, or control
beyond current requirements.
4-6
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The next priority for emission reductions is the control of
emission sources that do not emit benzene, or the application of
additional control for these sources can be considered as
mitigating actions. The hierarchy for control of air pollutants
other than benzene is to control other HAPs, followed by the
control of non-HAP VOCs. For example, the control of product
storage tanks or barge loading may result in the reduction of
emissions of other HAPs or VOCs even if benzene is not present.
Another example is a source, not covered by the Benzene Waste
Operations NESHAP/ that is controlled by a condenser or carbon
adsorber with an efficiency of 95 percent. If the source
installs a vapor incinerator to replace the existing control, the
incremental reduction from 95- to 98-percent control can be
considered a mitigating action. Additional emission reductions
in benzene, HAPs, and VOCs achieved by the vapor incinerator
would be considered as mitigation credits. All benefits accrue
for each mitigation action taken.
4.3 Example Facilities
This section presents several examples of baseline emissions
and proposed mitigating actions for facilities that may request a
waiver. An attempt has been made to illustrate some of the
different approaches that can be used for compliance and the
types of mitigating actions that could be considered in the
waiver application process. The examples indicate the new
compliance date of April 7, 1993. Actual compliance schedules
would have considerably more detail, e.g., more interim milestone
dates, than shown in the following examples. These examples are
abbreviated for illustrative purposes and are refinery oriented,
but the same basic concepts would apply to chemical plants and
coke by-product plants.
In these illustrations, the following weighting scheme has
been used. Any HAP other than benzene listed pursuant to
subsection (b) of Section 112, Title III of the Clean Air Act
Amendments of 1990, will have a weighting factor of 1.1 (i.e.,
1.1 Mg of other HAP can be used to mitigate 1 Mg of benzene).
4-7
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For non-HAP VOCs and SOx/ the weighting factor is 2.2 (i.e., 2,2
Mg of VOC or SOx are used to mitigate 1 Mg of benzene). Although
not explicitly stated in each example, the facility has followed
the mitigation hierarchies shown in Sections 3.2.2 and 4.2.
Facility 1
Compliance Approach; This facility is a petroleum refinery that
plans to comply with the NESHAP by steam stripping the major
wastewater streams that contain 10 ppm benzene, using carbon
adsorbers on slop oil tanks, and pretreating sludges for benzene
removal. Oil-water separators will be installed at the desalter
and product tanks to recover hydrocarbons from the water before
it is stripped. Wastes from maintenance activities and process
unit turnarounds sum to less than 2.0 Mg/yr benzene and will be
exempted under the small benzene quantity exemption.
Compliance Schedule:
• Oil-water separators controlled by carbon adsorbers will
be installed in the process units to separate and recover
any separate hydrocarbon phase from the desalter water
and drawdown from various product storage tanks.
Controlled conveyances will be used to transport the
wastes to the oil-water separator. The oil or product
will be returned directly to the process and the water
layer will be piped to a steam stripper. The controlled
separators will be installed by the old compliance date
(3/92) and will reduce benzene emissions from the
wastewater'system by 10 Mg/yr.
• Process wastewater that contains over 10 ppmw benzene,
primarily desalter water and tank drawdown from the oil-
water separators described above, will be piped to a
steam stripper for treatment. The steam stripper will
become operational by 10/93 and will reduce benzene
emissions by 10 Mg/yr.
• Controls will be installed on slop oil tanks by 4/93 and
will achieve a benzene emission reduction of 1 Mg/yr.
• Solvent extraction will be used to remove benzene from '
sludges generated by the oil-water separators by 4/93.
This will result in an actual benzene emission reduction
of 1 Mg/yr (after consideration of extractor emissions).
• "Overall, these controls will reduce benzene emissions
from waste operations from 26 Mg/yr to 4 Mg/yr.
Figure 4-1 presents a graphical illustration of the lost
benzene emission reductions in relation to Facility 1's
compliance schedule.
4-8
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Estimate "lost" benzene emission reduction and mitigation goal;
A description of the procedure used to estimate the
mitigation goal is given in Section 3.2.
• Lost emission reduction is 5 Mg:
- 10 Mg/yr x 0.5 yr = 5.0 Mg
This estimate is based on emissions from the steam stripper
(4/93 to 10/93); other activities to comply with the NESHAP, such
as the oil-water separator and slop oil tank controls, occur
before the new compliance date and thus do not enter into the
lost emission reduction calculation.
• Mitigation goal is 7.5 Mg:
- 5 Mg x 1.5 » 7.5 Mg.
Proposed mitigating actions;
1. This facility is located in a State that has established
regulations to control benzene and other volatile organic
compound emissions; consequently, there are limited opportunities
for other emission reductions (tanks, leaks, and process units
are generally controlled). As a mitigating action, the facility
proposes to steam strip additional process wastewaters with
benzene concentrations that range from 0.5 to less than 10 ppmw
(i.e., these streams do not have to be controlled under the
benzene waste NESHAP). This proposal would result in an
additional benzene air emission reduction of 2 Mg/yr; however,
the reductions would not be obtained until the steam stripper is
operational in 10/93. This mitigating action will be continued
past the end of the waiver period.
2. The action proposed in Item 1 will also result in air
emission reductions of toluene (0.62 Mg/yr), xylene (0.46 Mg/yr)
and miscellaneous VOCs (0.37 Mg/yr).
3. The additional benzene emission reduction through the
waiver period and continued for 2 years past the maximum waiver
period is 6.5 Mg:
2 Mg/yr x 1.25 yr + 2 Mg/yr x 2
(10/93 - 1/95) (1/95 - 1/97)
yr = 6.5 Mg
Reductions of other pollutants for the same period would be 2 Mg
for toluene, 1.5 Mg for xylene, and 1.2 Mg for miscellaneous
VOCs.
Evaluation;
The mitigating activities include a reduction of 6.5 Mg for
benzene emissions, 2.0 Mg of toluene, 1.5 Mg of xylene, and
1.2 Mg of miscellaneous VOCs. The equivalent reduction for HAPs
(toluene and xylene at 1.1 to 1) is 3.2 Mg, and the equivalent
4-10
-------
reduction for other VOCs is 0.5 Mg (at 2.2 to 1). The proposed
mitigation results in an equivalent reduction of 10 Mg (6.5 + 3.2
+ 0.5), which exceeds the mitigation goal of 7.5 Mg.
Figure 4-2 shows the actual mitigating reductions achieved
by Facility 1 based on the schedule of proposed actions.
Facility 2
Compliance Approach; This facility is a petroleum refinery that
plans to modernize their process sewer system. Process liquids
previously discharged to below grade will be managed in enclosed
systems above grade or in a double-contained system below grade.
The facility has submitted a compliance plan with two phases.
The first phase is based on compliance with an alternative
compliance option for site-specific risk. If the alternative
compliance option for site-specific risk is promulgated in August
1993, the facility plans to comply with the alternative
compliance option in October 1993. If the alternative compliance
option is not promulgated, the facility will implement the second
phase of the compliance plan and comply with the approach they
have outlined based on the requirements in the rule as amended on
January 1, 1993 by April 1994.
Compliance Schedule /rule as amended on January 7, 1993):
• Controls will be installed on slop oil tanks by 4/93 and
will achieve a benzene air emission reduction of 2 Mg/yr.
• Modifications to the wastewater collection and treatment
system will be completed by 10/93. This will achieve a
benzene air emission reduction of 29 Mg/yr.
• Tank drawdown will be piped to the enclosed wastewater
treatment system by 4/94 and will achieve a benzene air
emission reduction of 4 Mg/yr.
• After controls are implemented, benzene air emissions
from waste operations will be reduced from 37 Mg/yr to 2
Mg/yr.
Figure 4-3 presents a graphical representation of the lost
benzene emission reductions in relation to Facility 2's
compliance schedule for the rule as amended January 7, 1993.
Estimate "lost" benzene emission reduction and mitigation goal;
• Lost emission reduction is 18.5 Mg:
- 29 Mg/yr x 0.5 yr = 14.5 Mg (wastewater system)
- 4 Mg/yr x 1 yr = 4 Mg (tank drawdown)
• Mitigation goal is 28 Mg:
- 18.5 Mg x 1.5 = 28 Mg.
4-11
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Compliance Schedule falternative compliance option):
• For planning purposes, the alternative compliance option
is assumed to be promulgated in August 1993.
• A preliminary analysis by the company indicated that the
site-specific risk target in the alternative compliance
option could be met by reducing benzene emissions from
waste operations to 6 Mg/yr or less.
• The company proposes to implement controls on slop oil
tanks by 4/93 and to complete modifications to the
wastewater collection and treatment system by 10/93 (as
previously described). The alternative standard would be
met in 10/93 by reducing benzene emissions from 37 Mg/yr
to 6 Mg/yr.
• Tank drawdown would continue to be managed in the
existing uncontrolled wastewater collection system and
would not be controlled as described in the compliance
approach for the amended rule. However/ the combined
wastes from tank drawdown would be piped from the
existing collection system to the new enclosed treatment
system.
Figure 4-4 presents a graphical representation of the lost
benzene emission reductions for the alternative compliance
approach projected by Facility 2.
Estimate "lost* benzene emission reduction and mitigation goal:
• If the alternative compliance option is promulgated and
the facility achieves compliance as projected, the
mitigation goal is different from that given above for
compliance with the original rule. The lost benzene
emission reduction in this case is based on a shorter
waiver period from the new compliance date (April 1993)
to the time that compliance with the alternative
compliance option is achieved (October 1993).
• During the waiver period (4/93 to 10/93), the lost
reduction is 16.5 Mg:
- 29 Mg/yr x 0.5 = 14.5 Mg (wastewater system)
- 4 Mg/yr x 0.5 = 2 Mg (tank drawdown)
• The mitigation goal under the alternative compliance
option is 25 Mg:
- 16.5 Mg x 1.5 = 25 Mg.
Proposed mitigating actions;
1. Condensate from the flare system will be controlled to
obtain a benzene air emission reduction of 1 Mg/yr by 7/93. This
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waste has a benzene concentration of less than 10 ppm and is not
required to be controlled.
2. Secondary seals will be installed on floating roof tanks
by 1/94 to reduce benzene air emissions by 3 Mg/yr. The
frequency of leak detection and repair (LDAR) for equipment leaks
will be increased by 4/93 to obtain an annual benzene emission
reduction of 1.0 Mg/yr. Controls will be installed on marine
loading/unloading operations by 7/93 to obtain a benzene air
emission reduction 2 Mg/yr.
3. The quantity of benzene emissions voluntarily reduced in
Items 1 and 2 is 23 Mg up to January 1997:
Condensate: 1 Mg/yr x 3.5 yr - 3.5 Mg
Secondary seals: 3 Mg/yr x 3 yr = 9 Mg
LDAR: 1 Mg/yr x 3.75 yr = 3.8 Mg
Marine loading: 2 Mg/yr x 3.5 yr = 7 Mg
4. The controls described in Item 2 will also reduce air
emissions of other air pollutants, listed below in terms of the
emission reduction obtained during the period ending on
January 1, 1997:
Reductions of other pollutants (Mq)
Source TolueneXylene VOCs*
Secondary seals 2.0 1.0 1.6
LDAR 0.5 0.5 0.2
Marine loading 1.0 0.5 1.0
Total 3.5 2.0 2.8
* The individual organics were not identified; these compounds
include primarily C2 to Cg hydrocarbons.
Evaluation?
The mitigation proposed for this facility includes air
emission reductions of 23 Mg of benzene, 3.5 Mg of toluene, 2.0
Mg of xylene, and 2.8 Mg of VOCs. The value of these reductions
in terms of benzene is 29 Mg (the HAPs, toluene, xylene at 1.1 to
1, other VOCs at 2.2 to 1). The mitigation goal was 28 Mg based
on compliance with the rule as amended January 7, 1993, and 25 Mg
based on compliance with the alternative compliance option;
consequently, the mitigation credits exceed the mitigation goals.
Figure 4-5 shows the actual mitigating reductions achieved by
Facility 2 based on the schedule of proposed actions.
Facility 3
Compliance Approach: This facility is a petroleum refinery that
plans to control their existing wastewater collection and
treatment system. Traps will be installed on process drains,
4-16
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junction boxes will be covered (and vented to a control device if
necessary), oil-water separators will be controlled, and other
tanks will be covered and controlled up to the enhanced
biodegradation unit. In addition, slop oil tanks and sludge
handling processes will be controlled for benzene air emissions.
The facility also plans to implement a pollution prevention
technique by changing their desalting process. A light oil that
contains benzene is currently added to the desalter water to
improve the separation of oil and water; however, this light oil
contains benzene that increases the benzene concentration in the
water. This light oil will be replaced by a fuel oil that
contains no significant quantity of benzene, which will reduce
the amount of benzene removed with the desalter water. The
facility will be in compliance with the NESHAP by 4/94.
Compliance Schedule;
• Oil-water separators will be installed at the tank farm by
7/93 to recover oil and other product from the water
before it is discharged to the sewer. These separators
will be controlled by carbon adsorbers and will reduce
benzene emissions from the wastewater system by 8 Mg/yr.
• The pollution prevention process change from light oil to
a benzene-free oil will be completed by 4/94 and will
reduce benzene emissions from the wastewater by 15 Mg/yr.
• Modifications to the wastewater collection and treatment
system will be completed by 4/94. This will achieve a
benzene emission reduction of 20 Mg/yr.
• Controls will be installed on slop oil tanks and sludge
management units by 4/93 and will achieve a benzene
emission reduction of 2 Mg/yr.
Figure 4-6 illustrates the lost benzene emission reductions
in relation to Facility 3's compliance schedule.
Estimate "lost" benzene emission reduction and mitigation goal:
• Lost emission reduction is 37 Mg:
- 8 Mg/yr x 0.25 yr * 2 Mg (tank drawdown)
- 15 Mg/yr x 1 yr = 15 Mg (desalter water)
- 20 Mg/yr x 1 yr = 20 Mg (wastewater system)
(Since slop oil tank and sludge unit emissions are
controlled before 4/93, these emissions are not included
in the lost benzene calculation.)
• Mitigation goal is 56 Mg:
- 37 Mg x 1.5 • 56 Mg.
4-18
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Proposed mitigating actions;
1. Secondary seals will be installed on floating roof tanks
and fixed-roof tanks will be vented to a control device by 4/93
to reduce benzene emissions by 5 Mg/yr. The frequency of leak
detection and repair will be increased by 4/93 to obtain an
annual benzene emission reduction of 3 Mg/yr. Controls will be
installed on marine loading/unloading operations by 7/93 to
obtain a benzene emission reduction 4 Mg/yr. The additional
benzene air emission reduction up to January 1997 is 44 Mg (19 Mg
for secondary seals, 11 Mg for leak detection, and 14 Mg for
marine loading).
2. The controls described in Item 1 will also reduce air
emissions of other air pollutants, listed below in terms of the
emission reduction obtained up to January 1997:
Reductions of other pollutants (Ma)
Source Toluene Xvlene Other orqanics*
Secondary seals 4.0 1.0 2.0
Leaks 0.5 0.5 0.6
Marine loading 3.0 1.0 2.8
Total 7.5 2.5 5.4
* The individual organics were not identified; these compounds
include primarily C2 to Cg hydrocarbons.
Evaluation;
The proposed mitigation includes 44 Mg of benzene, 10 Mg of
other HAPs valued at 9.1 Mg, and 5.4 Mg of other VOCs valued
at 2.5 Mg. The mitigation credits of 56 Mg equals the goal
of 56 Mg.
Figure 4-7 shows the accumulation of mitigating reductions
for Facility 3 based on the schedule of proposed actions.
Facility 4
Compliance Approach; This facility is a large, old petroleum
refinery that plans to modernize their process sewer system;
• Process liquids previously discharged to below grade will be
managed in enclosed systems above grade or in a double-
contained system below grade.
• Wastewater treatment tanks, such as the oil-water separator
and dissolved air flotation unit, will be equipped with
emission control devices. Tanks that manage the recovered
slop oil will also be controlled.
4-20
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• Tank water draws will be controlled by hardpip:_r.g to the
wastewater treatment system.
Compliance Schedule;
• Controls will be installed on slop oil tanks by 4/93 and wiJ
achieve a benzene emission reduction of 2 Mg/yr.
• The new wastewater treatment system will be installed by 1/9
and will reduce benzene emissions by 44 Mg/yr (compliance
will be achieved one year after the end of the maximum waive
period).
Figure 4-8 illustrates the lost benzene emission reductions
based on Facility 4's compliance schedule.
Estimate "lost" benzene emission reduction and mitigation goal;
• Lost emission reduction is 121 Mg:
- 44 Mg/yr x 2.75 yr » 121 Mg (wastewater system)
• Mitigation goal is 182 Mg:
- 121 Mg x 1.5 - 182 Mg.
Proposed mitigating actions;
1. Secondary seals will be installed on floating roof tanks
and fixed-roof tanks will be vented to a control device by 1/94
to reduce benzene emissions by 10 Mg/yr. The frequency of leak*
detection and repair will be increased by 4/93 to obtain an
annual benzene emission reduction of 12 Mg/yr. Controls will be
installed on marine loading/unloading operations by 7/93 to
obtain a benzene emission reduction 8 Mg/yr. [Note: A standard
is under development for this source category; emission
reductions are credited towards the mitigation goal up to the
compliance date of the standard.] The additional benzene air
emission reduction up to January 1997 is 103 Mg (30 Mg for seals,
45 Mg for leak detection, and 28 Mg for marine loading).
2. The controls described in Item 1 will also reduce
emissions of other air pollutants, listed below in terms of the
emission reduction obtained up to January 1997.
Reductions of other pollutants (McM
Source TolueneXvleneOther VOCs*
Secondary seals 6 5 2.8
Leaks 9 6 2.2
Marine loading 5 4 3.2
Total 20 15 8.2
* The individual organics were not identified; these compounds
include primarily C2 to Cs hydrocarbons.
4-22
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3. In April 1993 the facility will switch from direct
contact steam and direct contact cooling water to indirect
heating and cooling for a specific process unit. These wastes
are not required to be controlled by the benzene waste NESHAF or
other rules. This pollution prevention action will result in a
decrease in waste quantity and the quantity of pollutants
discharged to the environment. Emissions of benzene from
condenser vents and from the cooling water tower will be reduced
by 6 Mg/yr for benzene, 2 Mg/yr for toluene, and 1 Mg/yr for
xylene. The emission reductions expected up to January 1997 will
be 23 Mg for benzene, 7.5 Mg for toluene, and 3.8 Mg for xylene.
Evaluation;
The mitigating activities in Items 1 and 3 result in a
reduction credit of 126 Mg of benzene. The reductions of other
HAPs (toluene and xylene) total 46 Mg, which provides an
equivalent of 42 Mg of reduction credit (at 1.1 to 1). Other
VOCs are reduced by 8.2 Mg, which yields an equivalent of 3.7 Mg
of reduction credit (at 2.2 to 1). The total equivalent
reduction shown in Figure 4-9 is 172 Mg (126 + 42 + 3.7), which
is 95 percent of the mitigation goal of 182 Mg.
Consequently, a waiver is not automatically granted.
However, owners or operators are free to suggest other actions
and conditions not listed in this document as part of their
waiver application. Acceptance of such actions or conditions is
subject to the discretion of the reviewing authority (Regional
office, State, or other delegated agency).
4-24
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4.4 References
1. USEPA. Compilation of Air Pollutant Emission Factors.
EPA-AP-42. Research Triangle Park, N.C.
2. USEPA. Procedures for Establishing Emissions for Early
Reduction Compliance Extensions Volume 1. EPA-450/3-91-
012a. February 1992.
3. USEPA. Estimating Air Toxics Emissions From Organic Liquid
Storage Tanks. EPA-450/4-88-004. October 1988.
4. USEPA. Hazardous Waste Treatment/ Storage/ and Disposal
Facilities (TSDF)—Air Emission Models. EPA-450/3-87-026.
November 1989.
5. Industrial Wastewater Volatile Organic Compound Emissions -
Background Information for BACT/LAER Determinations. EPA:
CTC, EPA-450/3-90-004. January 1990.
6. USEPA. Protocols for Generating Unit-Specific Emission
Estimates for Equipment Leaks of VOC and VHAP. EPA-450/3-
88-010. Research Triangle Park, NC. October 1988.
7. 40 CFR Part 60, Appendix A, Test Method 2, Determination of
Stack Gas Velocity and Volumetric Flow Rate (Type S pitot
tube) and Test Method 18, Measurement of Gaseous Organic
Compound Emissions by Gas Chromatography.
8. Field Evaluation of a Sludge Dewatering Unit at British
Petroleum Oil Refinery, Lima, Ohio, Vol. I, PEI Associates,
prepared for EPA: ORD, EPA Contract No. 68-02-4284, May,
1990. (See Docket F-90-CESP, Item S00474).
9. Field Evaluation of a Sludge Dewatering Unit at a Midwestern
Refinery, Vol. I, International Technology Corporation,
prepared for EPA:ORD, EPA Contract No. 68-02-4284, February
1991. (See Docket F-91-CESP, Item S00490).
10. Summary of Organic Air Emission Test Results for a Hazardous
Waste Fixation Process at Chem-Met Services, Inc.,
Wyandotte, Michigan, October 28, 1991. (See Docket F-92-
CESA, Item S00013).
4-26
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5.0 WAIVER REVIEW AND IMPLEMENTATION
5.1 Waiver Application
As previously noted, the basic procedure for applying for a
waiver is established in Section 61.10 of the General Provisions
to 40 CFR Part 61; in addition, the criteria specified therein
will also be used in the EPA review process. A request for a
waiver must be in writing and, in addition to the requirements of
61.10, include:
a) A demonstration that the owner/operator has made a good
faith effort to comply with the NESHAP on time, and an
explanation of why compliance will be delayed.
b) A description of the planned approach for bringing the
facility into compliance with the benzene waste operations
NESHAP. If an integrated or cluster approach to compliance is
selected, the owner/operator should describe how the approach
satisfies the NESHAP requirements, as well as other environmental
regulatory and statutory requirements. Facilities that apply for
waivers but anticipate meeting an alternative compliance option
based on site-specific risk should submit waiver applications
that reflect a two-phased compliance path.
c) A schedule for design, construction, and implementation
of the compliance approach.
d) Calculation of the benzene emission mitigation goal, as
explained in Section 3 of this document.
e) Description of the proposed mitigating actions to
compensate for lost benzene emission reductions. The source
owner/operator should discuss the availability of each of the
categories of mitigating actions identified in Section 3 of this
document. The description should include the types and
5-1
-------
quantities of pollutants that will no longer be released into the
environment. The owner/operator or waiver applicant should also
include a description of what monitoring devices will be
installed, maintained, and operated to ensure that any control
devices (e.g., a carbon adsorber or vapor incinerator) used for
mitigating actions are achieving the required emission reduction
quantities. Control device monitoring requirements also should
be included as conditions in the waiver agreement.
f) A demonstration that the actions proposed above in (d)
are either not required by existing regulations or statutes, are
provided in advance of upcoming regulations or statutes, or
exceed the requirements of current regulations or statutes.
The deadline for having an approved waiver is the new
compliance date (April 7, 1993). Any source that fails to comply
with Subpart FF, the benzene waste operations NESHAP as amended,
by April 7, 1993 and has not obtained an approved waiver by the
above deadline will be in violation of the NESHAP and, therefore,
may be subject to enforcement action.
5.2 Definition of Good Faith Efforts
Prior to final' action on the rule, owners and operators of
affected facilities were to some extent unsure of what control
requirements and alternative compliance options ultimately would
be contained in the Benzene Waste Operations NESHAP. As a result
of this uncertainty, some owner/operators may have delayed the
selection of a compliance strategy until an informed decision
could be made (i.e., until final action on the rule amendments).
The selected compliance strategy will vary depending on the
requirements and structure of the NESHAP, the costs and equipment
requirements, and timing/scheduling requirements based on the
particular facility's site-specific circumstances. Furthermore,
some applicants are awaiting development of a site-specific risk
option and cannot be certain of what compliance path to take.
5-2
-------
Due to this uncertainty, the demonstration of good faith
efforts to comply with the NESHAP on time should not be limited
solely to the purchase and installation of relevant control
equipment. Actions such as following and participating in the
rulemaking, conducting cost-benefit analyses of compliance
strategies applicable to the facility, performing engineering
design of related equipment necessary for compliance at the
facility/ monitoring development of the site-specific risk
option, and conducting preliminary or preparatory risk
assessments, as well as purchasing and installing control
equipment should be considered good faith efforts to comply with
the rule in a timely manner. In demonstrating good faith efforts
each applicant should explain why what they did or did not do in
relation to the standard was reasonable under their specific
circumstances.
5.3 Waiver Review
The owner/operator of the facility is fully responsible for
providing the necessary information to the EPA and demonstrating
the need for the waiver. If a facility owner/operator provides
insufficient or ambiguous information, the EPA should ask the
facility owner/operator to provide the needed information and
allow the owner/operator a reasonable amount of time to provide
additional information substantiating their waiver request. The
EPA will review the application in accordance with this guidance
document to confirm the calculations, the appropriateness of the
proposed mitigating actions, and adequacy of the benzene waste
operations emissions control compliance strategy. An owner or
operator will be notified prior to the denial of a waiver request
and given an opportunity to present additional information or
arguments before a final determination is made.
The EPA Regional (or delegated State or local agency) staff
reviewing waiver applications should make every effort to inform
the applicant of the completeness of their application as early
as possible. It should also be noted that if the application for
5-3
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a waiver is completed following the guidance presented in this
document, then (assuming the application is completed correctly)
there is certainty of waiver application approval. If other
approaches or procedures are used in applying for a waiver, then
the applicant should be aware that by further complicating the
waiver application review process, an element of uncertainty
regarding application approval has been introduced. Facility
owners and/or operators therefore are encouraged to follow this
guidance document in completing waiver applications. However, in
no case will a waiver application be rejected solely because the
applicant used procedures or methodologies outside those
contained in this guidance document or in some manner did not
fulfill all the conditions specified in this guidance in
completing their waiver application.
Any waiver issued by the Administrator will be in writing
and will identify the sources covered, specify a date the waiver
expires, specify dates by which steps toward compliance are to be
taken, and specify any additional conditions which the
Administrator determines necessary to assure protection of public
health during the waiver period. It is important to note that
applicable reporting requirements for the NESHAP will not be
waived. The waiver conditions should include a requirement for
reporting and owner/operator certification on a regular basis to
ensure that the facility is complying with the conditions of the
waiver agreement in a timely manner. The EPA is recommending
quarterly reporting (i.e., 4 times per year) during the waiver
and mitigating period; however, State and local agencies may
require other periods. Any violation of the waiver conditions
may result in the immediate revocation of the waiver, subjecting
the source to enforcement action for operation in violation of
Subpart FF without a waiver.
5.4 Title V Permits
The waiver agreement that the source owner/operator must
sign will be incorporated in the Title V operating permit issued
5-4
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to the source at the beginning of the waiver period or as soon as
possible thereafter. If the source's compliance program extends
beyond January 7, 1995, the maximum waiver period of two years,
the compliance requirements specified in the waiver agreement
that extend beyond two years will be incorporated into a judicial
consent decree as well as the Title V permit. The permit will
merely reflect the underlying requirements imposed by the waiver
and the consent decree. The waiver and consent decree will
remain as the primary basis for enforcement action should a
conflict arise. Any modification of the compliance schedule
first must be made as an amendment to the waiver or consent
decree; this is then followed by a modification to the operating
permit.
If the operating permit program is not yet available in the
applicable State, then affected sources will not need permits;
.however, compliance with the subpart, waiver, and consent decree
conditions will still be required.
5.5 Consent Decrees
If the source owner/operator has signed a waiver agreement
committing to a compliance program extending beyond January 7,
1995, the maximum two year waiver period, then at the end of the
two year waiver, the source will be considered in violation of
Subpart FF. To avoid5 being penalized for noncompliance, the
waiver agreement (and permit) must further require that at the
end of such a waiver period the source owner/operator sign a
consent decree to be lodged and entered by the court. If full
compliance with the Subpart including mitigating credits can be
obtained within one year after the expiration of the waiver,
then, at the discretion of the EPA, a Section 113(a)
administrative order may be used instead of a judicial consent
decree. To reduce the likelihood of adverse enforcement action,
a source owner/operator should approach the EPA before the end of
the two year waiver to negotiate a judicial consent decree or
5-5
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administrative order. Such a decree or order must embody a
compliance schedule to complete the installation of all equipment
necessary to achieve full compliance, and to achieve the required
mitigation credits.
During the waiver period, if the source owner/operator meets
the schedule originally committed to in the waiver agreement, the
EPA will be prepared to agree to a compliance schedule in the
judicial consent decree (or administrative order) that reflects
the originally agreed upon time-table for compliance. A consent
decree is required to resolve noncompliance beyond the two year
waiver period because of the EPA's policy against no action
assurances (i.e., the EPA cannot guarantee that an enforcement
action will not be taken if a facility or source is out of
compliance.) It is not anticipated that the EPA will penalize
source owner/operators that are maintaining the schedule
committed to in the waiver agreement. It is also the intention
of the EPA to negotiate such consent decrees before the end of
the waiver period, so that these decrees can be lodged with the
court and subsequently entered as soon as the waiver expires.
The consent decrees cannot be filed with the court before the
waiver expires because there is no violation before that time and
the court would be without jurisdiction to enter a decree when
there is no case or controversy. If a source fails to meet the
conditions of the waiver, enforcement action could be taken which
could lead either to penalties or resolution by a consent decree.
5.6 Amending Waiver Agreements
Owners and operators of affected facilities that need to
change their compliance and/or mitigation strategy during the
waiver period will be allowed to amend the waiver agreement if
the conditions listed below are met. Amendments must be
negotiated with the appropriate Regional, State, or local
authority and not implemented unilaterally. The applicant must
demonstrate that the facility was in compliance with the
conditions of the waiver up to the date that the request for
5-6
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amendment is made. The applicant must also demonstrate that any
change to the benzene mitigation goal or the mitigation
quantities resulting from the proposed amendment to the
compliance or mitigation strategy will be accounted for in the
conditions to the amended waiver agreement.
5.7 Failure to Achieve Mitigating Benefits
If a source comes into compliance with Subpart FF by the end
of a waiver, and the waiver agreement requires additional
emission reductions that go beyond the waiver period, the source
is not relieved of the obligation to achieve the mitigating
emission reductions merely because compliance with Subpart FF
control requirements has been achieved. If the source
subsequently fails to achieve the mitigating emission reductions
that were committed to, this failure shall be considered a
violation of the Title V permit and the waiver agreement,
enforceable pursuant to the authority of Section 113.
5-7
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APPENDIX A
PROCEDURES TO DETERMINE BENZENE EMISSIONS
FROM WASTE OPERATIONS
A.I Estimates Using Fraction Emitted
The basic procedure used to estimate benzene emissions from
waste operations relies on determinations made by each facility
as to the quantity and benzene concentration of all of their
waste streams. The facility must also identify the types of
waste management units that are used for the treatment, storage,
or disposal of the waste. The types of waste management units
are then matched with the units listed in this appendix to
determine an estimate of the fraction emitted. This procedure
estimates emissions from the waste quantity times the benzene
concentration times the fraction emitted, all in consistent
units. If multiple units are used in series, the emission
estimate for a subsequent unit must account for the benzene
emitted in previous units.
For example, assume that the waste is processed in 3 units
with fractions emitted of 0.2, 0.5, and 0.3. In this case, 20
percent is emitted in the first unit, 40 percent of the original
benzene quantity is emitted in the second unit (0.5 x (100 -
20)), and 12 percent is emitted in the third unit (0.3 x (100 -
20 - 40)) for a total fraction emitted of 0.72. In general, the
overall fraction emitted (fe) can be calculated from the
individual fractions emitted (fj. to fn) :
Estimates of fraction emitted for various types of waste
management units are summarized in Table A-l. These estimates
were used in the analysis of impacts associated with the NESHAP
and were derived from typical (or model) unit parameters for each
A-l
-------
type of source. Table A-l provides a simple means to obtain
rough estimates of benzene emissions from different types of
waste operations. This simplified approach is provided to avoid
the tedious calculations that would otherwise be required for
each waste management unit at each site. In addition,
approximation of emissions using the factor(s) in Table A-l is
adequate for the purpose of this waiver guidance.
Alternative approaches are available for those facilities
that wish to perform more rigorous site-specific emission
modeling. The operating characteristics of each unit (surface
area, depth, retention time, etc.) can be used in the emission
models provided in References 2 and 3 to generate an estimate of
the fraction of benzene emitted for that unit. For facilities
with complex waste management systems, the modeling approach can
be labor-intensive (time consuming) and may provide only a
marginal improvement in accuracy.
The emission control efficiencies associated with the
controls expected to be used in response to the benzene waste
NESHAP generally range from 95 to 99 percent. Consequently, an
estimate of 100 percent reduction is reasonably close for
estimating the lost benzene emission reduction. For those
facilities that want to adjust their estimate to account for
emissions after control, the following control efficiencies are
recommended:
Cover and vent to a control device 95 percent
Thin-film evaporation (waste treatment) 98 percent
Steam strip (waste treatment) 99 percent
Submerged filling of containers 65 percent
Waste incineration 99.99 percent
Additional details on the estimated control efficiencies can
be found in analysis of impacts for the rule — Docket Item
IV-B-4 in Docket A-89-06.
A-2
-------
TABLE A-l. ESTIMATES OF FRACTION OF BENZENE EMITTED
FROM WASTE MANAGEMENT OPERATIONS1'2
Waste management unit
Fraction emitted
Container loading and storage 0.0014
Filtration/dewatering 0.63
Fixation (solidification) 0.68
Surface impoundment 0.76
Landfill (includes fixation) 0.72
Land treatment 0.93
Tanks - aqueous wastes 0.11
Tanks - covered, non-aqueous wastes 0.00065
Tank truck loading 0.0014
Wastewater treatment system (covered separator)3 0.47
Wastewater treatment system (open separator)3 0.72
A wastewater treatment system includes the collection system
(i.e., drains, junction boxes, lift stations, etc), an oil-
water separator, a DAF unit, an equalization basin, a
clarifier, and a biobasin.
(Revised February 25, 1993)
A-3
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TABLE A-l. ESTIMATES OF FRACTION OF BENZENE EMITTED
FROM WASTE MANAGEMENT OPERATIONS1f2
Waste management unit Fraction emitted
Container loading and storage 0.14
Filtration/dewatering 0.63
Fixation (solidification) 0.68
Surface impoundment 0.76
Landfill (includes fixation) 0.72
Land treatment 0.93
Tanks - aqueous wastes 0.11
Tanks - covered/ non-aqueous wastes 0.00065
Tank truck loading 0.14
Wastewater treatment system (covered separator)3 0.47
Wastewater treatment system (open separator)a 0.72
a A wastewater treatment system includes the collection system
(i.e., drains, junction boxes, lift stations, etc), an oil-
water separator, a DAF unit, an equalization basin, a
clarifier, and a biobasin.
A-3
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A.2 Alternative Procedures
For certain types of sources, alternative procedures are
available to determine benzene emissions. If the source is a
process vent that is enclosed and easily sampled, emission
measurements by approved EPA methods are acceptable. For cyclic
processes, the measurement must be representative of the typical
or worst case emission rate over the cycle. For floating or
fixed roof tanks, estimating procedures have been developed by
API and EPA to estimate emissions. Emission equations are
available in AP-424 and also in guidance documents developed for
EPA for early emission reduction programs (e.g., EPA-450/3-91-
012a, July 1991).5
. In general, direct emission measurements of open area
sources are not acceptable because emissions from these source
types are highly variable and direct measurement techniques,
conducted over a short-term period, are considered inaccurate
characterizations of long-term emissions. Consequently,
representative results are difficult to obtain. For these cases,
waste quantity and benzene concentration in the waste provide an
upper bound on the emission potential.
A.3 References
1. Final NESHAP for waste operations: Basis for impact
calculations. Docket Item IV-B-4 in Docket A-89-06.
February 16, 1990.
2. Industrial wastewater volatile organic compound
emissions - background information for BACT/LAER
determinations. EPA:CTC, EPA 450/3-90-004. January
1990.
3. USEPA. Hazardous Waste Treatment, Storage, and
Disposal Facilities (TSDF)—Air Emission Models.
EP-450/3-87-026. November 1989.
A-4
-------
4. USEPA. Compilation of Air Pollutant Emission Factors.
EPA-AP-42. Research Triangle Park, NC.
5. USEPA. Procedures for Establishing Emissions for Early
Reduction Compliance Extensions Volume 1. EPA-450/3-
91-012a. February 1992.
A-5
-------
APPENDIX B
BACKGROUND INFORMATION FOR REPORTING WASTES CONTAINING BENZENE
B.I What Types of Waste Streams Contain Benzene?
The waste streams of interest will be identified in the
initial 90-day report required by the rule, which provides
information on the waste quantity and benzene concentration of
each waste stream. An important step in estimating the baseline
benzene emissions is the proper identification of these streams
and the determination of benzene concentration and waste quantity
as specified by the rule. Examples of the types of wastes that
should be included in the analysis are summarized below; this
list is not all inclusive.
B.I.I Process Wastewater and Other Process Wastes
Many processes at petroleum refineries, chemical plants, and
coke by-product recovery plants use or generate water, and when
this water contacts organic materials that contain benzene, a
waste containing benzene is generated. Process wastewater that
contains benzene usually is generated from direct contact between
water or steam and an organic material that contains benzene.
The benzene may be dissolved in the water phase (up to about
1,800 ppm at 25°C), and in addition, the benzene may be carried
in an organic phase that is mixed in or emulsified with the
water.
For example, water washes are used to remove water soluble
contaminants from feedstock, intermediate, or product. In the
petroleum refining industry, crude oil is desalted by mixing with
water and then separating off the water layer. The water removes
salts from the crude oil; however, benzene is also extracted from
the crude oil by the water, and incomplete separations introduce
a layer of hydrocarbon into the desalter wastewater.
B-l
-------
When direct contact steam is used for heating or direct
contact water is used for cooling a material that contains
benzene, an aqueous waste containing benzene is generated.
For example/ when direct contact steam is used in a distillation
unit, water condenses in the overhead system along with lighter
organics. The water, contaminated with the organics it has
contacted, is usually separated from the organic layer in a
decanter.
Wastes from production processes can also include sludges,
organic (i.e., less than 10% water content) wastes, and wastes
with multiple phases. Sludges can be generated from spent
catalyst or the settling of suspended solids. Organic wastes,
such as spent solvents or recovered product, are also generated
in some production processes. Each of these wastes should be
identified by the facility if it contains benzene. Although
process wastewater with benzene is a primary source of benzene
emissions, organic wastes and sludges can contain significant
quantities of benzene that will be emitted if these wastes are
not managed in a manner that controls air emissions.
B.I.2 Tank Drawdown
Wastes from tank drawdown are generated when water is
separated from feed stock, intermediate, or product in a storage
tank. The water may be present from prior processing or from
rainfall that enters the tank. Tank drawdown is usually mostly
water; however, depending on the completeness of the separation
and degree of emulsification, the waste may also contain a
hydrocarbon phase.
B.I.3 Wastes from Maintenance and Cleaning
Maintenance wastes that contain benzene are generated from
routine activities such as draining a pump for repairs, draining
low points in a pipe, and cleaning or repair of equipment such as
B-2
-------
filters, sight glasses, and analyzers. The wastes that are
generated may be organic materials that contain benzene (or even
pure benzene), wastewater, or wastes with multiple phases.
Maintenance and cleaning wastes are often drained to or
washed down into the wastewater collection system. They are
generated on an irregular basis and may be highly variable in
quantity and benzene concentration. The quantities associated
with these wastes are generally much smaller than the quantities
associated with process wastewater.
B.I.4 Wastes from Process Unit Turnaround
Wastes containing benzene can be generated as a result of
"turnarounds" of process units such as a reactor, catalytic
cracking unit, or distillation column. Process unit turnarounds
generally involve the scheduled shutdown or temporary cessation
of operations of a process unit and its associated tanks and
equipment, after a period of operation, in order to perform
maintenance and repair work or to change production operations.
As part of the turnaround operations, water or steam typically is
used to remove residual organic materials from the unit. As are
maintenance wastes, process unit turnaround wastes may be highly
variable in quantity and benzene concentration. Wastes are also
generated from "turnarounds" when production in certain units is
stopped to perform maintenance or to change production
operations. Water or steam is used to remove residual organic
material from the unit, thereby generating a benzene containing
waste. s •
B.I.5 Wastes from Waste Management Activities
Wastes may be generated during activities associated with
the treatment, storage, or disposal of wastes. For example,
landfill leachate may contain benzene if it is generated from the
disposal of benzene wastes. Remediation activities may also
generate wastes such as contaminated soil or water that contains
B-3
-------
benzene. The treatment of oily wastewater in decanters or other
units may generate new wastes in the form of sludges, wastewater,
or recovered hydrocarbons. Condensate that contains benzene may
be generated from a flare system for waste gases and vapors.
B.2 What Are Common Mistakes in Reporting Benzene Wastes?
The rule amendments (published on January 1, 1993) are
designed to clarify several issues associated with what wastes
are covered by the rule and where waste quantity and benzene
concentration determinations are made. Some of the most common
mistakes that were made in determining the applicability of the
rule are summarized here. Many of these errors relate to the
determination of the total annual benzene-in-waste quantity
(TAB).
B.2.1 Determinations are Made Prior to Treatment
The benzene concentration and waste quantity are determined
prior to any waste treatment, including decanting in an oil-water
separator or treatment in a steam stripper. The rule states that
these determinations are made at the point of generation. In
general, the point of generation is where the waste leaves the
process unit, before treatment or loss of benzene to the
atmosphere. Exceptions specifically noted in the rule include
sour water strippers at petroleum refineries and ammonia
strippers at coke by-product recovery plants.
B.2.2 Including Wastes That Have Less Than 10 Percent Water
in the TAB
A waste is not excluded from the reporting requirements if
the organic portion of the waste is recovered and returned to the
process. All wastes that contain over 10 percent water or that
mix with water at any time so that the resulting mixture contains
over 10 percent water, are included in the determination of TAB.
B-4
-------
For example, wastes that initially contain less than 10 percent
water are included in the TAB if they are discharged to the
wastewater collection system.
B.2.3 Failure to Count Wastes Exempted From Control as Part of
TAB
Wastes that may be exempted from control (e.g.,
concentration less than 10 ppm benzene, low waste quantity, low
benzene quantity) are included in the reporting and determination
of TAB unless otherwise noted in the rule. Wastes that will not
be controlled even when the facility is in compliance with
Subpart FF do not contribute to the baseline of lost benzene
emission reduction, and should not be included in the lost
benzene emission reduction calculation. However, the control of
these exempted streams can be considered a mitigating action.
B.2.4 Failure to Include the Benzene in All Phases of the Waste
When wastes contain multiple phases, the benzene in all
phases is included in the determination of benzene concentration
and TAB. (Some facilities analyzed only the water phase of two
phase wastes. The organic phase could have benzene
concentrations that are 50 to 100 times the benzene concentration
in the water.)
B-5
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APPENDIX C
LIST OF ENVIRONMENTAL REGULATIONS AFFECTING THOSE FACILITIES
UNDER THE BENZENE WASTE OPERATIONS NESHAP
There are four types of facilities that are affected by the
Benzene Waste Operations NESHAP: petroleum refineries; chemical
plants; coke by-product plants; and waste treatment, storage, and
disposal facilities. Below is a list of environmental air
regulations that might possibly affect these types of facilities.
This list is not all inclusive; it is provided solely to
assist reviewers and applicants. The applicant remains
responsible for certifying that mitigating actions will be taken
in advance of Federal/State/local regulations, or exceed the
requirements of these regulations.
CLEAN AIR ACT (CAA)
[42 U.S.C. §§7401 - 7642]
• National Emission Standards for Hazardous Air
Pollutants
[40 CFR Part 61]
Subpart F- Vinyl Chloride
Subpart J - Equipment Leaks (Fugitive Emission
Sources) of Benzene
Subpart L - Benzene Emissions from Coke By-
product Recovery Plants
Subpart V - Equipment Leaks (Fugitive Emission
Sources)
Subpart Y - Benzene Emissions from Benzene
Storage Vessels
Subpart BB - Benzene Emissions from Benzene
Transfer Operations
• Standards of Performance for New Stationary Sources
[40 CFR Part 60]
Subpart E - Incinerators
Subpart G - Nitric Acid Plants
Subpart H - Sulfuric Acid Plants
Subpart J - Petroleum Refineries
Subpart O - Sewage Treatment Plants
Subparts T through X - Phosphate Fertilizer
Industry
Subpart PP - Ammonium Sulfate Manufacture
C-l
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Subpart W - Equipment Leaks of VOC in the
Synthetic Organic
Manufacturing Industry
Subpart XX - Bulk Gasoline Terminals
Subpart ODD - VOC Emissions from the Polymer
Manufacturing Industry
Subpart G6G - Equipment Leaks of VOC in Petroleum
Refineries
Subparts K, - Storage Vessels for Petroleum
Ka, and Kb Liquids
Subpart NNN - SOCMI Distillation Operations
Subpart QQQ - VOC Emissions from Petroleum
Refinery Wastewater Systems
Hazardous Organic NESHAP [under development]
MACT Standards for Petroleum Refineries [under
development]
Diesel Fuel Quality Standards [40 CFR §80.29]
VOC Emissions from Tank Vessel Loading Operations
[under development]
Accidental Release Risk Management Plans [11/93]
Oxygenated Fuel Requirements [8/91]
Volatility Regulations for Gasoline and Alcohol Blends
sold in 1992 and Beyond [40. CFR §80.27]
Reformulated Gasoline and Anti-Dumping Rules [11/91]
Fuel and Fuel Additives Diesel Fuel Quality and Sulfur
Content et al. [40 CFR Part 80 + 86]
Lead Ban in Gasoline [11/91]
Steady Progress Requirements in Nonattainment Areas
[notice 7/91]
C-2
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APPENDIX D
POLICY FOR GRANTING WAIVERS OF COMPLIANCE
[The following excerpt from the preamble of the final amendments
to the Benzene Waste Operations NESHAP, promulgated on January 7,
1993, addresses the EPA policy for granting waivers under the
benzene waste operations NESHAP.]
Owners and operators of existing sources subject to a NESHAP
promulgated under the Clean Air Act prior to the 1990 Clean Air
Act Amendments must be in compliance with the rule within 90 days
of the rule's effective date, unless a waiver of compliance is
granted by the Administrator. The period for a waiver may not
exceed 2 years beyond the effective date of the rule. For a
NESHAP, the effective date is the date of promulgation in the
FEDERAL REGISTER.
To resolve confusion about Subpart FF, the EPA chose to stay
the effectiveness of the rule while clarifying amendments were
developed. The effective date for the amended rule is today's
date (January 7, 1993), and existing sources must be in
compliance within 90 days of today's date (by April 7, 1993)
unless a waiver of compliance is granted by the Administrator.
The owner or operator of an existing source unable to come
into complete compliance with the NESHAP for existing waste
operations within 90 days of the effective date of this rule may
apply for a waiver of compliance in accordance with the
procedures described in 40 CFR §§61.10 and 61.11. One
requirement of those provisions is to demonstrate that the
additional time is necessary for the installation of controls.
In addition, as the EPA stated in the March 5, 1992 proposal, the
EPA believes that it is essential that the risk to human health
from benzene emissions be mitigated. The EPA believes that the
best way to mitigate the benzene emission reductions that will be
lost due to delayed compliance during the waiver period is to
reduce benzene emissions elsewhere at the facility. However, in
some instances it may not be technically or economically feasible
to achieve such benzene emissions reductions. Accordingly, in
the preamble to the proposed rule the EPA indicated that it would
consider various other types of environmentally beneficial
activities that could be credited (on a discounted basis) towards
the mitigation goal. In the preamble to the proposed rule
amendments, the EPA set forth a hierarchy of activities (see 57
FR at 8026) .
One commenter objected to the broad degree of available
mitigation options. The commenter expressed concern over the
ability of the EPA to determine whether the mitigation made up
for the lost benzene emission reductions where the mitigation
included emission reduction or nonhazardous air pollutants,
D-l
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nonair emission reductions and nonquantifiable pollution
reduction projects. The commenter requested that only benzene
emissions be credited for mitigation or at least that mitigation
be limited to reductions of other hazardous air pollutants with a
weighting factor included.
The EPA understands the concern about the uncertainty in
equating one type of emissions reduction with a reduction of
another pollutant or in another media, and, as a result, the
final mitigation policy is somewhat narrower than outlined in ,the
proposed rule.
It remains the EPA's policy that a source should seek to
reduce other benzene emissions first, where such reductions are
technically and economically feasible. However, because of (1)
the unique nature of this rule; (2) the efforts made thus far by
sources seeking to comply with the benzene waste NESHAP; (3) the
relatively short period of time that remains for submitting
waiver applications; (4) the conditions for granting a waiver are
more restrictive than announced in the proposal notice; and (5)
the departure set forth herein is consistent with efforts to
resolve litigation brought by both environmental and industry
parties, the EPA is providing opportunities to achieve the
mitigation goal through projects involving the reduction of
pollutants other than benzene when projects to reduce benzene
emissions are not technically and economically feasible.
Thus, the EPA has determined that a source seeking a waiver
must determine and achieve its mitigation objective as follows.
First, the source must determine the additional amount of benzene
emissions that will be emitted to the air from emission points
subject to Subpart FF as compared with the emissions expected if
the source complied with that standard without a waiver. Second,
the source must multiply that amount by 1.5. This quantity,
expressed in kilograms, becomes the source's mitigation goal.
Then a source must identify how it will achieve that goal.
The EPA will continue to give the highest priority to
obtaining reductions of other benzene air emissions to meet this
mitigation goal. Thus, a source must include in its waiver
application all emission reduction projects for benzene, where it
is technically and economically feasible to achieve such benzene
reductions. If a source undertakes a benzene project (having
determined it to be technically and economically feasible based
on the benzene reductions to be achieved) that also achieves
coincidental reductions of other hazardous air pollutants (HAP's)
or volatile organic compounds (VOC's), the source may include as
a mitigation credit those coincidental reductions on a discounted
basis as described below.
If a source demonstrates that there are no other technically
and economically feasible projects to reduce benzene emissions
D-2
-------
and that as a result of those projects it still cannot achieve
its mitigation goal, the EPA will accept additional projects
supplying reductions of other HAP's listed under Section 112 of
the Clean Air Act as amended in 1990 at a ratio of 1.1 kilograms
of other such pollutants per kilogram of the source's unmet
mitigation goal.
If a source demonstrates that emission reduction projects
supplying sufficient reductions of other HAP's are not available,
the EPA will accept additional projects resulting in reductions
of VOC's, at a ratio of 2.2 kilograms of such pollutant per
kilogram of the source's unmet goal.
Mitigation may not be credited if the reduction is to meet
any other regulatory requirement. However, if a source achieves
early compliance with some future regulatory requirement, it can
be credited with the reductions which occur up to the time the
requirement goes into effect.
Finally, the EPA will consider waiver applications for up to
three projects involving reductions of sulfur oxides (SOX) , if
the sources seeking these reductions demonstrate that adequate
reductions of benzene, other HAP's, and VOC's are not available
at their facilities. These sources must provide at least 2.2
kilograms of SOX for each kilogram of credit towards the
mitigation goal. The EPA believes it is appropriate to consider
these projects in this case only because the planning for these
projects may already be far advanced and it may not be feasible
for such sources to develop other mitigation projects in time to
apply for a waiver.
The EPA is adopting the mitigation principles set forth
above for this rule because of the reasons outlined above. The
interpollutant provisions of this action do not establish any
precedent for future actions.
For Subpart FF, the EPA believes the waiver policy described
in the March 5, 1992 notice of proposed rulemaking is a
legitimate exercise of the Administrator's discretionary
authority to grant waivers of compliance under Section 112 of the
Clean Air Act. This policy was discussed in the preamble to
provide information to potential waiver applicants and not to
indicate that the policy was part of the proposed rule amendments
proposed for comment. The only requirement related to waiver
applications in the proposed rule amendments was that waiver
applicants include, with their application under §61.10, a plan
that is an enforceable commitment to obtain environmental
benefits to mitigate the benzene emissions that result from
delayed compliance. This requirement is retained in the final
rule. The criteria for judging whether an application for
waiver of compliance for Subpart FF is acceptable have been
D-3
-------
established by the Administrator under his discretionary
authority for granting waivers.
D-4
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TECHNICAL REPORT DATA
(ftettt raWAuovcfKMU on On smrw ktfon tomfkHnti
1. RtPORT NO. 3.
EPA 453/R-93-010
4. TITLE ANO SU0TITU
Benzene Haste Operations NESHAP -
Waiver Guidance Document
». AUTHQHISI
1. PERFORMING ORGANIZATION NAME ANO AOORESS
Office of Air Quality Planning and Standards
US Environmental Protection Agency
Research Triangle Park, HC 27711
12. SPONSORING AOCMCY NAMC ANO ADORES*
Office of Air Quality Planning and Standards
US Environmental Protection Agency
Research Triangle Park, NC 27711
k. RECIPIENT'S ACCESSION NO.
t REPORT OATI _
January 199:
L PERFORMING ORGANIZATION COO<
1. PERFORMING ORGANIZATION REPQf
10. PROGRAM CLEMENT NO.
II. CONTRACT/QUANT NO.
68-D1-0118, WA 55
is. TYPE of REPORT ANO PCRIOO eovi
Final
M. sroNSoniNo AOCNCY coot
EPA/200/04
It. SUF* LEMENTARY MOTE*
I*. ABSTRACT
Subpart FF of 40 CFR Part 61 addresses benzene emissions
from waste operations at petroleum refineries, chemical
manufacturing plants, coke by-product plants, and waste
management units that manage wastes from these facilities.
Subpart FF, also known as the benzene waste operations national
emission standards for hazardous air pollutants (NESHAP), was
amended and published in the Federal Register on January 7, 1993.
Facilities unable to comply with the NESHAP by April 7, 1993, may
apply for a waiver of compliance for a period that shall not
extend beyond January 7, 1995. As a condition of the waiver,
facilities will be required to mitigate benzene air emissions
that result from the delay in compliance with the NESHAP. This
document outlines the goals and objectives of the benzene waste
NESHAP waiver policy, and provides guidance for preparing,
reviewing and evaluating waiver requests.
IT.
KCY WORDS ANO DOCUMENT ANALYSIS
i. ocscftirrofts
benzene waste
emissions NESHAP
refinery coke by-products
mitigation waiver
chemical manufacturing
1*. DISTRIBUTION STATEMENT
Release Unlimited
b.lOCNTIFIERS/OrtN ENOEO TERMS
air pollution
control
1C. SECURITY CLASS iTTta Kepvrti
Unclassified
2O. SECURITY CLASS (Thuptfei
Unclassified
c. COSATI Field/Clou
21. NO. OF PACES
103
22. PRICE
?•*<• 2230-1 («•*. 4-77) PNCVIOW* COITION i* O«»OLKTC
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