[Federal Register Volume 65, Number 13 (Thursday, January 20, 2000)]
[Proposed Rules]
[Pages 3169-3187]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: X00-10120]



[[Page 3169]]

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 63

[AD-FRL-6523-9]
RIN 2060-AH81


National Emission Standards for Hazardous Air Pollutants for 
Source Categories: Organic Hazardous Air Pollutants From the Synthetic 
Organic Chemical Manufacturing Industry and Other Processes Subject to 
the Negotiated Regulation for Equipment Leaks

AGENCY:  Environmental Protection Agency (EPA).

ACTION:  Proposed rule; amendments.

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SUMMARY:  On April 22, 1994 and June 6, 1994, the EPA issued the 
``National Emission Standards for Hazardous Air Pollutants for Source 
Categories: Organic Hazardous Air Pollutants from the Synthetic Organic 
Chemical Manufacturing Industry and Other Processes Subject to the 
Negotiated Regulation for Equipment Leaks.'' This rule is commonly 
known as the Hazardous Organic NESHAP or the HON. Today's action 
proposes amendments to the definition of the term ``process vent'' and 
proposes to add procedures for identifying ``process vents'' in order 
to ensure consistent interpretation of the term. The EPA is also 
proposing revisions to several provisions to the rule to reflect the 
terminology used in the revised definition of process vent. These 
changes are being proposed to reduce the burden associated with 
developing operating permits for facilities subject to the rule. 
Today's action also proposes to add provisions to allow off-site 
control of process vent emissions and to add provisions for 
establishing a new compliance date under certain circumstances. The EPA 
is also proposing to add to appendix C of part 63 another procedure for 
use in determining compliance with wastewater treatment requirements. 
The EPA is also proposing corrections and clarifications to other 
provisions of the rule to ensure that the rule is implemented as 
intended.
    These proposed amendments to the rule will not change the basic 
control requirements of the rule or the level of health protection it 
provides. The rule requires new and existing major sources to control 
emissions of hazardous air pollutants to the level reflecting 
application of the maximum achievable control technology.

DATES:  Comments must be received on or before February 22, 2000, 
unless a hearing is requested by January 31, 2000. If a hearing is 
requested, you must submit your comments on or before March 6, 2000.

ADDRESSES:  Address your comments to: Air and Radiation Docket and 
Information Center (6102), Attention Docket Number A-90-19 (see docket 
section below), Room M-1500, U.S. Environmental Protection Agency, 401 
M Street, SW, Washington, DC 20460. If possible, please submit two 
copies of your written comments. You may also submit comments 
electronically in WordPerfect<Register> version 5.1, 6.1, or Corel 8 
file format (or ASCII) by electronic mail (e-mail) to: a-and-r-
<a href="/cdn-cgi/l/email-protection" class="__cf_email__" data-cfemail="baded5d9d1dfcefadfcadbd7dbd3d694dfcadb94ddd5cc">[email protected]</a>.
    Public Hearing. If a public hearing is held, EPA will hold the 
hearing at the EPA's Office of Administration Auditorium, Research 
Triangle Park, North Carolina. Persons interested in attending the 
hearing or wishing to present oral testimony should notify Janet Eck, 
U.S. Environmental Protection Agency, Research Triangle Park, NC 27711, 
telephone (919) 541-7946.
    Docket. Docket No. A-90-19 contains the supporting information for 
the original NESHAP and this action. You may inspect this docket and 
copy materials between 8:00 a.m. and 5:30 p.m., Monday through Friday. 
The EPA's Air and Radiation Docket and Information Center is located at 
Waterside Mall, Room M-1500, first floor, 401 M Street, SW, Washington, 
DC 20460. The telephone number for the Air Docket and Information 
Center is (202) 260-7548 or 260-7549. You may have to pay a reasonable 
fee for copying materials.

FOR FURTHER INFORMATION CONTACT:  Dr. Janet S. Meyer, Coatings and 
Consumer Products Group, at (919) 541-5254 (<a href="/cdn-cgi/l/email-protection" class="__cf_email__" data-cfemail="48252d312d3a66222926082d382925292124662d3829662f273e">[email protected]</a>). 
The mailing address for the contact is Emission Standards Division (MD-
13), U.S. Environmental Protection Agency, Research Triangle Park, 
North Carolina 27711.

SUPPLEMENTARY INFORMATION:  Docket. The docket is an organized file of 
the information considered by the EPA in the development of this 
rulemaking. The docket is a dynamic file, because material is added 
throughout the rulemaking development. The docketing system is intended 
to allow members of the public and industries involved to readily 
identify and locate documents so that they can effectively participate 
in the rulemaking process. Along with the proposed and promulgated 
standards and their preambles, the contents of the docket, except for 
certain interagency documents, will serve as the record for judicial 
review. (See the Act section 307(d)(7)(A).)
    Electronic Comments. If you submit comments by e-mail, your 
comments must be submitted as an ASCII file avoiding the use of special 
characters and any form of encryption. You may also submit comments on 
a diskette in WordPerfect<Register> version 5.1, 6.1, or Corel 8 file 
format (or ASCII). You must identify the docket number A-90-19 at the 
beginning of your comments. You should not submit confidential business 
information (CBI) through e-mail. You may file electronic comments 
online at many Federal depository libraries.
    Regulated Entities. The regulated category and entities affected by 
this action include:

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           Category                  Examples of regulated entities
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Industry.....................  Synthetic organic chemical manufacturing
                                industry (SOCMI) units, e.g., producers
                                of benzene, toluene, or any other
                                chemical listed in table 1 of 40 CFR
                                part 63, subpart F.
------------------------------------------------------------------------

    This table is not intended to be exhaustive but, rather, provides a 
guide for readers regarding entities likely to be interested in the 
revisions to the regulation affected by this action. This action is 
expected to be of interest to owners and operators subject to this rule 
who have process vents that may be affected by these rule amendments 
and to those owners or operators who are sending vent streams (gas 
streams) to another facility for disposal. Entities potentially 
regulated by the HON are those which produce as primary intended 
products any of the chemicals listed in table 1 of 40 CFR part 63, 
subpart F and are located at facilities that are major sources as 
defined in section 112 of the Clean Air Act (Act). Potentially 
regulated entities generally are companies that manufacture industrial 
organic chemicals and cyclic organic crude and intermediates. To 
determine whether your facility is

[[Page 3170]]

regulated by this action, you should carefully examine all of the 
applicability criteria in 40 CFR 63.100. If you have questions 
regarding the applicability of this action to a particular entity, 
consult Janet Meyer (See FOR FURTHER INFORMATION CONTACT).
    Outline. The information presented in the preamble is organized as 
follows:

I. Background on the Rule
II. Proposed Process Vent Changes
A. Process Vent Definition and Identification of Gas Streams that 
Meet the Definition
B. Reporting Requirements Associated with Proposed Change to the 
Definition of Process Vent
C. Miscellaneous Conforming Edits
III. Off-Site Control or On-Site Third Party Control of Process Vent 
Emissions
IV. Compliance Schedules
V. Miscellaneous Corrections and Clarifications
A. Subpart F
B. Subpart G
C. Clarification of Compliance Demonstration Requirements for Flares
D. Appendix C to Part 63
VI. Administrative Requirements
A. Executive Order 12866: Regulatory Planning and Review
B. Executive Order 13084: Consultation and Coordination with Indian 
Tribal Governments
C. Executive Order 13045: Protection of Children from Environmental 
Health Risks and Safety Risks
D. Executive Order 13132 on Federalism
E. Unfunded Mandates Reform Act
F. Regulatory Flexibility/Small Business Regulatory Enforcement 
Fairness Act of 1996
G. Paperwork Reduction Act
H. National Technology Transfer and Advancement Act

I. Background on the Rule

    On April 22, 1994 (59 FR 19402), and June 6, 1994 (59 FR 29196), 
the EPA (we) published in the Federal Register the NESHAP for the 
synthetic organic chemical manufacturing industry (SOCMI), and for 
several other processes subject to the equipment leaks portion of the 
rule. These regulations were promulgated as subparts F, G, H, and I in 
40 CFR part 63, and are commonly referred to as the hazardous organic 
NESHAP, or the HON. We have published several amendments to clarify 
various aspects of the rule since the April 22, 1994 Federal Register 
publication of the rule. See the following Federal Register documents 
for more information: September 20, 1994 (59 FR 48175); October 24, 
1994 (59 FR 53359); October 28, 1994 (59 FR 54131); January 27, 1995 
(60 FR 5321); April 10, 1995 (60 FR 18020); April 10, 1995 (60 FR 
18026); December 12, 1995 (60 FR 63624); February 29, 1996 (61 FR 
7716); June 20, 1996 (61 FR 31435); August 26, 1996 (61 FR 43698); 
December 5, 1996 (61 FR 64571); January 17, 1997 (62 FR 2721); August 
22, 1997 (62 FR 44608); and December 9, 1998 (63 FR 67787).
    In June 1994, the Chemical Manufacturers Association (CMA) and Dow 
Chemical Company (Dow) filed petitions for review of the promulgated 
rule in the U.S. Court of Appeals for the District of Columbia Circuit, 
Chemical Manufacturers Association v. EPA, 94-1463 and 94-1464 (D.C. 
Cir.) and Dow Chemical Company v. EPA, 94-1465 (D.C. Cir). The 
petitioners raised over 75 technical issues on the rule's structure and 
applicability. The petitioners raised issues regarding details of the 
technical requirements, drafting clarity, and structural errors in the 
drafting of certain sections of the rule. On August 26, 1996, we 
proposed clarifying and correcting amendments to subparts F, G, H, and 
I of part 63 to address the issues raised by CMA and Dow on the April 
1994 rule. On December 5, 1996 and January 17, 1997, we took final 
action on the amendments proposed on August 26, 1996. On August 22, 
1997, we proposed corrections to the definition of ``enhanced 
biological treatment systems or enhanced biological treatment process'' 
and conforming edits to appendix C of part 63 to reflect these changes 
to the definition. On December 9, 1998, we took final action on the 
amendments proposed on August 22, 1997.

II. Proposed Process Vent Changes

A. Process Vent Definition and Identification of Gas Streams that Meet 
the Definition

    In today's amendments, we are proposing to: (1) revise the 
definition of the term ``process vent''; and (2) add a new section 
63.107 to subpart F to provide instructions for identifying gas streams 
that meet the definition of the term ``process vent.'' These proposed 
changes are intended to make it easier to implement the rule and to 
ensure consistent interpretation of the term ``process vent.'' We 
expect the proposed changes to reduce the burden associated with 
permitting facilities under the Operating Permit Program while 
maintaining the intended applicability of the rule.
    Currently, the rule defines a ``process vent'' as:

* * * a gas stream containing greater than 0.005 weight percent 
total organic hazardous air pollutants that is continuously 
discharged during operation of the unit from an air oxidation 
reactor, other reactor, or distillation unit (as defined in this 
section) within a chemical manufacturing process unit that meets all 
applicability criteria specified in Sec. 63.100(b)(1) through (b)(3) 
of this subpart. Process vents are gas streams that are discharged 
to the atmosphere (with or without passing through a control device) 
either directly or after passing through one or more recovery 
devices. Process vents exclude relief valve discharges, gaseous 
streams routed to a fuel gas system(s), and leaks from equipment 
regulated under subpart H of this part.

Our intent in this definition is to define a ``process vent'' from its 
point of origination within a chemical manufacturing process unit--
``from an air oxidation reactor, other reactor, or distillation 
unit''--to where it is ultimately discharged to the atmosphere. Once a 
process vent is identified under the HON, applicability of control 
requirements to the gas stream is determined after the last recovery 
device (if any recovery devices are present) but prior to the inlet of 
any control device that is present and prior to release to the 
atmosphere. The objective of this approach is to ensure that 
applicability of the rule remains with the operation creating the gas 
stream.
    In recent months, industry representatives have stated that they 
understand the definition to define a process vent as the discharge 
point to the atmosphere. These industry representatives have raised 
concerns that our interpretation of the definition would significantly 
alter the information that must be submitted as part of an operating 
permit application and included in an operating permit. Specifically, 
industry representatives have expressed concerns that because a process 
vent is an ``emission point,'' the operating permit rule would require 
submittal of information on all gas streams originating from HON 
process units and all processes receiving these gas streams. Because 
HON process units frequently send gas streams to numerous other process 
units throughout a plant site, they have argued that it would be very 
burdensome to provide information on every gas stream originating from 
a HON process unit. Industry representatives have also questioned 
whether this language could result in some people classifying process 
equipment (such as downstream distillation units and reactors) as 
control equipment.
    We considered the implementation issues associated with the 
existing definition of ``process vent'' and concluded that a new 
approach toward identification of gas streams subject to the control 
requirements would be appropriate. This approach consists of: (1) 
Defining a process vent as a discharge point instead of as a gas 
stream; (2) adding a section to subpart

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F to ennumerate characteristics of gas streams that when discharged 
would be subject to the process vent provisions; and (3) adding 
additional reporting requirements to Sec. 63.151 and Sec. 63.152 to 
ensure that the point of origination of a gas stream is identified as 
well as the point of discharge. This group of amendments is expected to 
achieve the outcome that was originally intended while addressing 
implementation problems.
1. New Definition of Process Vent
    We are proposing to revise the definition of ``process vent'' to 
read:

* * * the point of discharge to the atmosphere (or the point of 
entry into a control device, if any) of a gas stream if the gas 
stream has the characteristics specified in Sec. 63.107(b) through 
(h) of this subpart or meets the criteria specified in 
Sec. 63.107(i) of this subpart. For purposes of Secs. 63.113 through 
63.118, all references to the characteristics of a process vent 
(e.g., flow rate, total HAP concentration, or TRE index value) shall 
mean the characteristics of the gas stream.

Under this definition, the emission points that would be identified as 
process vents in the permit application and the operating permit would 
be the points of discharge to the atmosphere of a gas stream (meeting 
certain criteria) created by a HON chemical manufacturing process unit.
2. Section 63.107--Identification of Process Vents
    We are proposing to add a new section, Sec. 63.107, to subpart F to 
specify the characteristics that distinquish those gas streams that 
were intended to be regulated as process vents from gas streams that 
were never intended to be regulated as process vents. In order to do 
this, we have identified: (1) Those characteristics that a gas stream 
must have in order for the discharge to be subject to the process vent 
provisions; (2) those characteristics that would exclude a gas stream 
from such applicability; and (3) criteria for prevention of 
circumvention. We do not intend for proposed Sec. 63.107 to impose any 
recordkeeping requirement for the determination of process vents 
associated with chemical manufacturing process units subject to the 
HON. Our intent is for this section to ennumerate the characteristics 
of gas streams that on ultimate discharge would be regulated as a 
process vent.
    Characteristics of Process Vents. Proposed Sec. 63.107 specifies 
that the gas stream must originate from an air oxidation reactor, 
distillation unit, or other reactor. This proposed section includes the 
same flow and concentration criteria used in the existing definition of 
process vent. Paragraphs (b) through (g) of this proposed section also 
provide a more complete description of the flow characteristics of the 
gas stream than is currently provided by the definition. These 
paragraphs address the flow characteristics of the gas stream, the 
manner of discharge of the gas stream, and the location of discharge of 
the gas stream.
    Exclusions from the process vent definition. The proposed 
Sec. 63.107 also specifies gas streams that on ultimate discharge would 
not be subject to the process vent provisions of the rule. These 
exclusions are listed in proposed paragraph (h). They include items 
previously excluded from the definition such as relief valve discharges 
and gas streams routed to fuel gas systems. We have also included in 
paragraph (h) an exclusion for productive uses of gas streams and an 
exclusion for gas streams that are regulated under other sections of 
the rule.
    In paragraph (h)(5), we have provided that if a gas stream is sent 
to another process for reaction or other productive use in another 
process, it is not considered to be a gas stream which would be subject 
to the HON control requirements. In such cases, the control 
requirements would be determined with respect to the process that 
ultimately discharges the gas stream to the atmosphere. For example, if 
a HON process unit sends a gas stream containing butadiene to a process 
unit producing polybutadiene rubber, the gas stream would be subject to 
requirements of 40 CFR part 63, subpart U (Group I Polymers and Resins) 
assuming that other applicability criteria for that rule are met.
    Paragraph (h)(6) provides that gas streams that are transferred for 
fuel value are also not considered to be process vents. In this case, 
the gas stream is being used as, or with, primary fuel for process 
heaters or other combustion devices and as such will be efficiently 
combusted.
    Also, to avoid potential misunderstandings, we are clarifying that 
the following gas streams are not considered process vents at the 
discharge point: (1) Gas streams discharged to the atmosphere from 
control devices subject to Sec. 63.113, (2) gas streams from storage 
vessels, (3) gas streams from transfer operations, (4) gas streams from 
waste management units, and (5) gas streams from process analyzers. 
These gas streams were not intended to be addressed by the process vent 
requirements of the rule. These gas streams are being explicitly 
excluded in this proposed approach to remove any potential ambiguity 
concerning applicability of the process vent requirements.
    Activities of concern. We are also proposing to add a new paragraph 
Sec. 63.107(i), which lists certain activities of concern to the EPA. 
The listed activities are similar to (and if not listed in paragraph 
(i), might have been mistaken for) certain productive uses that are 
excluded from the definition of ``process vent.'' To avoid possible 
misunderstandings, paragraph (i) provides that the listed activities do 
not avoid the ``process vent'' requirements of subpart G. In other 
words, if there would have been a process vent in the absence of these 
activities, there is still a process vent.
    For example, streams that change from the gas phase to the liquid 
phase are normally not subject to ``process vent'' requirements. 
However, it may be possible for an owner or operator to temporarily 
liquefy a gas stream without a valid process purpose simply to avoid 
classifying the emission point as a process vent. The proposed 
paragraph (i) specifies that, in such a case, the emission point is 
still a process vent.
    As a second example, gas streams are often routed, for a valid 
process purpose, through other process equipment before discharge. In 
such cases, although some standards under part 63 may classify the 
emissions from other process equipment as ``process vent'' emissions, 
the HON does not. However, we are concerned that an owner or operator 
might route a gas stream to a piece of equipment, such as a storage 
vessel, without a valid process purpose simply to avoid having the 
process vent requirements apply. Paragraph (i) provides that any 
routing of a gas stream through equipment without a process purpose 
does not avoid the ``process vent'' requirements. In this regard, we 
also wish to clarify that for purposes of paragraph (i), providing 
inert ``padding'' for a storage vessel is not considered to be a 
process purpose.
    As a third example, gas streams that are used as fuels are normally 
not subject to the ``process vent'' requirements of the HON. However, 
we are concerned that an owner or operator might interpret this to 
allow routing a gas stream to a substandard flare or incinerator (one 
that was not designed to achieve the destruction efficiency required by 
subpart G) and saying the stream is not a process vent. Regardless of 
whether combustion of the gas stream in a substandard flare or 
incinerator is a fuel use, it is also a form of emission control that 
does not comply with the

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standards of subpart G. Consequently, paragraph (i) specifies that 
streams used in this manner are not exempt from any ``process vent'' 
requirements that would otherwise apply. We wish also to clarify that 
the wording ``a flare that does not meet the criteria in section 
63.11(b) or an incinerator that does not reduce emissions of organic 
hazardous air pollutants by 98 percent or to a concentration of 20 ppm 
by volume'' in paragraph (i) is intended to describe the design 
characteristics of the flare or incinerator, not the actual performance 
at any given moment. An excursion, in which a flare or incinerator 
temporarily fails to achieve those requirements, would not cause the 
gas stream to trigger the process vent requirements.

B. Reporting Requirements Associated with Proposed Change to the 
Definition of Process Vent

    We are also proposing to amend Sec. 63.151(e) and to add a new 
paragraph, Sec. 63.152(d)(4). These two paragraphs would require owners 
or operators to identify, for each process vent at the source, the 
chemical manufacturing process unit that creates the process vent, the 
type of unit operation that creates the vent stream, and either the 
last recovery device, if Group 2 process vent, or the control device 
and other equipment used for compliance. We consider submittal of this 
information to be an important part of the proposed change to define a 
process vent as a point of discharge to the atmosphere. This 
information is necessary to allow effective enforcement of the revised 
definition.

C. Miscellaneous Conforming Edits

    Today's proposed amendments also include proposed amendments to 
several provisions and definitions in the rule to reflect today's 
proposed definition of process vent. The proposed amendments include:
    <bullet> Revisions to the definition of ``Group 1 process vent,'' 
``Group 2 process vent,'' and ``vent stream'' to reflect the new 
definition of process vent as a point of discharge to the atmosphere.
    <bullet> Revisions to paragraphs (a)(3) and (c) of Sec. 63.113 to 
use the defined terms ``process vent'' and ``halogenated vent streams'' 
instead of the undefined terms ``vent'' and ``halogenated Group 1 
process vents.''
    <bullet> Revisions to the second sentence in Sec. 63.114(a)(3) to 
use the defined term ``process vent'' instead of the term ``vent,'' 
which is not defined in the rule.
    <bullet> Revisions to Sec. 63.114(d) to reflect the proposed 
revisions to the definition of process vent. The proposed changes are: 
(1) To monitor any bypass line for potential by-passes that could 
divert the gas stream to the atmosphere instead of monitoring for 
diversions from a control device; and (2) to specify that this 
obligation applies between the origin of the gas stream and the point 
where the gas stream reaches the process vent. These changes are a 
necessary part of the revised approach toward definition of a process 
vent.
    <bullet> Revisions to several paragraphs in Sec. 63.115 and 
Sec. 63.116 and to Sec. 63.117(a)(6), Sec. 63.117(a)(8), and 
Sec. 63.118(e)(1) to use the term ``vent stream'' instead of ``process 
vent stream.'' This change is being proposed because the gas stream is 
not a process vent and to use a defined term.
    <bullet> Revisions to Sec. 63.117, paragraph (a) introductory text 
to refer to the defined term ``Group 1 process vents'' instead of 
``Group 1 process vent streams.''
    <bullet> Revision of paragraph (a)(4)(iv) of Sec. 63.117 to refer 
to ``vent streams introduced with combustion air * * * '' This revision 
is being proposed to reflect the proposed change in terminology.

III. Off-Site Control or On-Site Third Party Control of Process 
Vent Emissions

    Today's proposed amendments include provisions to address the 
transfer off-site or to a third party on-site for disposal gas streams 
that have the characteristics of a process vent (specified in proposed 
Sec. 63.107(b) through (h)) or meet the criteria in proposed 
Sec. 63.107(i) and that have the characteristics of Group 1 process 
vents. We would add these proposed amendments to 40 CFR 63.113 as a new 
paragraph (i). Presently, the rule does not address situations where a 
gas stream is sent to another facility or a third party for disposal. 
Consequently, there is some ambiguity concerning who is responsible for 
compliance activities. We are proposing to add these provisions to 
address this oversight in the original drafting of the rule.
    The proposed provisions to allow off-site or on-site third party 
control would require the owner/operator transferring the gas stream to 
comply with the provisions specified in 40 CFR 63.114(d) prior to 
transfer. The owner or operator may not transfer the gas stream unless 
the transferee has submitted to EPA a written certification that the 
transferee will manage and control, in accordance with subpart G, any 
gas streams that meet the characteristics of a Group 1 process vent at 
the point of transfer that were received from a source subject to the 
requirements of subparts F and G. The proposed provisions require the 
owner or operator to notify the third party that the gas stream has to 
be handled and controlled in accordance with the requirements of the 
rule.
    The proposed provisions would require that statements of compliance 
with the rule by a third party need only be submitted to EPA; the 
provisions do not contain or envision any requirement that EPA approve 
the written statements before transfers of such gas streams to off-site 
facilities are permitted. The proposed provisions provide, however, 
that EPA may take enforcement action against the transferee in the 
event that the transferee violates the pertinent HON process vent 
provisions.
    We are proposing to clarify this compliance approach in recognition 
that in some instances gas streams subject to the HON process vent 
provisions are now being sent to another facility or a third party for 
disposal. We are doing this to provide a means to allow transfers of 
control responsibility without imposing liability for actions of 
another party on the owner or operator of the HON source.
    Definition of point of transfer. We are also proposing to add a 
definition of ``point of transfer'' to subpart G. This proposed 
definition is used to specify the location where the applicability of 
control requirements is determined (i.e., where the total resource 
effectiveness (TRE) index value is determined) in situations where a 
gas stream is sent to a third party for disposal. This term is used in 
the proposed provisions for off-site control or on-site control not 
owned or operated by the source (Sec. 63.113(i)).
    Reporting requirements associated with off-site or third party 
treatment option. Today's proposed action also includes proposed 
amendments to Sec. 63.152 (b)(6) and (c)(4)(iv), and adds a paragraph 
(d)(4) to require reporting of the name and location of the transferee, 
the identification of the Group 1 process vent, and changes in the 
identity of the transferee. These reports are necessary to permit 
effective enforcement of the proposed provisions in Sec. 63.113(i) for 
third party disposal of gas streams.

IV. Compliance Schedules

    We are proposing to amend Sec. 63.100 by adding a paragraph (q) to 
allow establishment of site-specific compliance dates under three 
circumstances. The first circumstance concerns situations where the 
transferee does not elect to submit a certification and ceases to 
accept the gas stream for disposal. The second circumstance concerns 
situations where the transferee had previously submitted a written 
certification and later revokes the written certification. The third

[[Page 3173]]

circumstance applies to cases where the inability to meet the 
applicable compliance date arises due to today's proposed amendments 
and is not one of the previously described situations.
    For all three of these requests, the owner or operator must submit 
a proposed compliance schedule and a justification for the time 
requested. For cases where the need for additional time to comply with 
the rule arose solely due to today's proposed amendments, the owner or 
operator must also submit an explanation of why they need a new 
compliance date in addition to the previously mentioned proposed 
compliance schedule and justification. In addition, for cases when the 
transferee revokes the certification, the owner or operator must also 
submit an explanation of why they need a new compliance date and a 
description of the measures that will be taken to minimize excess 
emissions until the new compliance date. In your description of 
measures to minimize emissions, you must include a schedule when each 
measure will be first implemented and how and to what extent the 
measure will reduce emissions. For the last two cases, we would review 
the request for the compliance extension for the right to have 
additional time as well as the actual length of the compliance 
extension. In the first case, we would review only the length of 
compliance extension requested.
    We are proposing these amendments in recognition that the 
provisions concerning third party control of gas streams sent for 
disposal are potentially imposing new requirements. We are proposing to 
address these compliance timing issues through review of individual 
requests since the time required for sources to comply with these new 
provisions will depend on site-specific factors. The proposed 
requirement for mitigating measures to reduce emissions for situations 
where the transferee revokes certification is intended to ensure that 
all reasonable measures are taken to ensure that emissions are not 
increased.
    We further recognize that the proposed amendments to the definition 
of process vent and the proposed Sec. 63.107 may also affect the 
compliance status of some facilities. The intent of the proposed 
provisions allowing owners or operators to request a compliance 
schedule for these cases is intended to efficiently manage the effect 
of these proposed rule changes.

V. Miscellaneous Corrections and Clarifications

    We are also proposing to amend several additional paragraphs in 
subparts F and G to correct drafting errors and address oversights. 
These problems were identified during the review of the rule to address 
the implementation issues associated with the rule's definition of 
process vent. In addition, we are proposing amendments to some of the 
wastewater provisions to correct drafting errors and oversights in 
those sections of the rule.

A. Subpart F

    Section 63.100(e). We are proposing to revise Sec. 63.100(e) by 
adding a new first sentence to the paragraph that states that the 
source is the collection of all chemical manufacturing process units at 
a major source that meet the applicability criteria in 
Sec. 63.100(b)(1) through (b)(3). We are also proposing several minor 
edits to Sec. 63.100(e) to reflect this additional sentence. We are 
doing this to make it clearer that the source is comprised of all the 
equipment and operations associated with the process units subject to 
the rule. We expect that this proposed revision should reduce questions 
concerning which equipment is considered to be in the source and 
thereby simplify reconstruction determinations.
    Batch process vent changes. We are proposing to amend 
Sec. 63.100(j)(4) and to add a definition of ``batch process vent'' to 
Sec. 63.101 to correct a drafting error. We are revising 
Sec. 63.100(j)(4) to refer to ``batch process vents'' instead of the 
term ``process vent.'' This change is necessary because, in the rule, 
the term ``process vent'' only applies to continuous discharges from 
specific types of equipment. As such, it was improperly applied to the 
case being addressed in Sec. 63.100(j)(4). To describe the type of 
operation that we intended to exclude by the provision in 
Sec. 63.100(j)(4), we are proposing to define ``batch process vent'' 
as:

    Batch process vent means gaseous venting to the atmosphere from a 
batch operation.
    Our intent with the process vent provisions of the rule was to 
address operations that created continuous gaseous discharges during 
the operation of the process unit.

B. Subpart G

    Section 63.110(a). We are proposing to amend Sec. 63.110(a) to 
include in-process equipment subject to Sec. 63.149 of subpart G. We 
overlooked the need to amend this paragraph in preparation of the 
January 17, 1997 amendments to the rule. Today's action would correct 
that error.
    Miscellaneous conforming edits to process vent provisions 
(Secs. 63.113 to 63.118). We are also proposing to amend several 
paragraphs in subpart G to improve consistency in terminology. These 
changes are:
    <bullet> Revision of Sec. 63.113(e) to refer to the defined term 
``TRE index value'' instead of ``TRE index.''
    <bullet> Revision of Sec. 63.113(g) to refer to ``total organic HAP 
concentration'' instead of ``concentration.'' This proposed change 
would correct unclear language in this paragraph.
    <bullet> Revision of the term ``gas stream flow'' in the 
introductory language to Sec. 63.114(a)(4)(ii) and in 
Sec. 63.114(a)(4)(ii)(C) to read ``gas flow rate.''
    We are also proposing to revise Sec. 63.118(a)(3) and (f)(3) to 
require records for periods when the gas stream is diverted to the 
atmosphere instead of records for periods when the gas stream is 
diverted from the control device. These revisions will make the 
recordkeeping requirement consistent with the monitoring requirement. 
We overlooked the need for these changes when we made the January 17, 
1997 amendments to the rule that revised the wording of the monitoring 
requirement.
    Miscellaneous amendments to wastewater provisions in Secs. 63.132 
through 63.147 and tables to subpart G. We are proposing changes to 
these sections of subpart G to address a number of minor drafting 
errors and oversights in the January 17, 1997 amendments to the rule. 
The sections and the associated proposed revisions are:
    <bullet> Sec. 63.132(a)(3) and (b)(4)--these paragraphs currently 
send the reader to the recordkeeping and reporting provisions in 
Secs. 63.146 and 63.147. However, at this time there is no explicit 
statement that Group 2 wastewater streams are also subject to the 
recordkeeping and reporting requirements despite table 15 of subpart G 
requiring such information. Today's proposal would explicitly specify 
these requirements for Group 2 wastewater streams and would add cross 
references for them to Sec. 63.132(a)(3) and (b)(4).
    <bullet> Sec. 63.138(i)--Today's proposed amendments are to clarify 
that in some cases, process wastewater streams included in the 1 
megagram (Mg) exemption from treatment requirements in Sec. 63.138(b) 
and (c) are also exempt from the suppression requirements in 
Secs. 63.133 through 63.137. In cases where the mass flow rate is 
determined at the point of determination, it was never our intent to 
require suppression

[[Page 3174]]

of these wastewater streams. We intended to require suppression of the 
partially treated streams that are part of the 1 Mg exemption option 
provided in Sec. 63.138(i)(2). The proposed amendments would also 
clarify that process wastewater streams included in the 1 Mg exemption 
must be identified in the Notification of Compliance Status for both 
options presented in Sec. 63.138(i). The current text inadvertently 
omitted stating this requirement explicitly for the option that 
requires all Group 1 wastewater streams at the source to have a mass 
flow rate less than 1 Mg per year (Sec. 63.138(i)(1)). (Identification 
of all Group 1 and Group 2 wastewater streams is currently required to 
be included in the Notification of Compliance in Table 15.)
    <bullet> Sec. 63.146(b)(1)--The proposal would add a statement of 
the reporting requirements for Group 2 wastewater streams. The proposed 
text is consistent with the information presently required by Table 15 
to subpart G. Paragraph (b)(1) is presently a reserved paragraph in 
subpart G.
    <bullet> Sec. 63.147(b)(8)--The proposed amendment would clarify 
the recordkeeping requirements for Group 2 wastewater streams. The 
proposed addition to this section is consistent with the information 
presently required by Table 15 to subpart G.
    <bullet> Sec. 63.147(d) introductory text, paragraphs (d)(2) and 
(d)(3)--The proposed amendments would clarify requirements for non-
regenerative carbon adsorbers. Section 63.147(d) only specifies the 
records to keep in lieu of daily averages for regenerative carbon 
adsorbers. Due to an oversight, the present rule text does not specify 
the required records for non-regenerative carbon adsorbers. Presumably, 
without today's correction, facilities operating non-regenerative 
carbon adsorbers would have to keep daily averages, which is not EPA's 
intent. Today's amendments would provide an alternative to daily 
averages for non-regenerative carbon adsorbers. The proposed amendments 
would also make this section of the rule consistent with Table 13 to 
subpart G.
    <bullet> Table 12 to subpart G--The proposed amendments would 
remove ``design'' and the reference to Sec. 63.138(d) from item 2 of 
the table. We intended that the continuous monitoring requirements 
specified in item 2 apply to all steam strippers used to comply with 
the wastewater provisions in subpart G, not just design steam 
strippers. Without this change, owners or operators of sources using 
steam strippers to comply with the wastewater treatment requirements 
are required to request approval of the monitoring parameters. It was 
not EPA's intent to require approval for these parameters.
    <bullet> Table 20 to subpart G--The proposed amendments would add 
requirements for non-regenerative carbon absorbers. These amendments 
are necessary because we omitted non-regenerative carbon adsorbers from 
this table. See discussion accompanying Sec. 63.147(d) for further 
explanation of the need for this amendment.
    Section 63.151(b)(1)(iii). We are proposing to correct a drafting 
error in Sec. 63.151(b)(1)(iii). This paragraph in the rule requires 
identification of the kinds of emission points within the chemical 
manufacturing process units that are subject to subpart G. The proposed 
amendment to Sec. 63.151(b)(1)(iii) would replace the phrase ``within 
the chemical manufacturing process unit'' with the phrase ``within the 
source.'' This change is necessary because wastewater streams are not 
included in the definition of the chemical manufacturing process unit, 
but they are part of the source regulated by the HON. Consequently, 
this reporting requirement does not accomplish its intended purpose. 
Therefore, we are proposing to revise Sec. 63.151(b)(1)(iii) to require 
identification of the kinds of emission points within the source that 
are subject to subpart G.

C. Clarification of Compliance Demonstration Requirements for Flares

    We are proposing amendments to Sec. 63.116(a), Sec. 63.128(b), 
Sec. 63.14(j), and Sec. 63.180(e) to clarify that a compliance 
demonstration for flares must be conducted using the provisions found 
in Sec. 63.11(b). Specifically, we are now specifying that the owner or 
operator must (1) conduct a visible emission test, (2) determine the 
net heating value of the gas being combusted, and (3) determine the 
actual exit velocity. In each case, we are specifying specific 
procedures required in 63.11(b) for the determination. We are adding 
this more explicit language to the rule to address questions concerning 
the obligation to do these compliance determinations. We intend this 
change to remove any doubt concerning the applicability of these 
requirements.

D. Appendix C to Part 63

    We are proposing to amend appendix C to part 63 to add a 
concentration measurement procedure for determining the fraction 
biodegraded (f<INF>bio</INF>) in biological treatment units that are 
not thoroughly mixed, and thus, have multiple zones of mixing. As part 
of these proposed revisions, we are proposing to add a Form XIII to 
appendix C to part 63, and we are proposing conforming edits to section 
I to refer to the new procedure in section III.E.
    The purpose of adding this new procedure, called Multiple Zone 
Concentration Measurements, to appendix C is to provide an alternative 
concentration measurement test that can be used for units with multiple 
zones of mixing. The present concentration measurement procedure in 
appendix C, called the Inlet and Outlet Concentration Measurement 
Procedure, can only be used for thoroughly mixed treatment units. To 
use this new multiple zone procedure, you would identify zones with 
substantially uniform characteristics and would measure representative 
organic compound concentrations within the biological treatment unit as 
well as the inlet and outlet of the biological treatment unit. The 
estimated mass transfer coefficient for each compound is determined 
using the characteristics of each zone. You calculate f<INF>bio</INF> 
for each compound and each zone using Form XIII.
    In addition to adding the Multiple Zone Concentration Measurements 
Procedure to appendix C, we are also proposing corrections to a term in 
Equation App. C-6 and to clarify that Equation App. C-4 is the solution 
to Equation App. C-3.

VI. Administrative Requirements

A. Executive Order 12866: Regulatory Planning and Review

    Under Executive Order 12866 (58 FR 51735, October 4, 1993), the EPA 
must determine whether a regulatory action is ``significant'' and, 
therefore, subject to Office of Management and Budget (OMB) review and 
the requirements of the Executive Order. The Executive Order defines 
``significant'' regulatory action as one that is likely to lead to a 
rule that may:
    (1) Have an annual effect on the economy of $100 million or more, 
or adversely affect in a material way the economy, a sector of the 
economy, productivity, competition, jobs, the environment, public 
health or safety in State, local, or tribal governments or communities;
    (2) Create a serious inconsistency or otherwise interfere with an 
action taken or planned by another agency;
    (3) Materially alter the budgetary impact of entitlements, grants, 
user fees, or loan programs, or the rights and obligations of 
recipients thereof; or
    (4) Raise novel legal or policy issues arising out of legal 
mandates, the

[[Page 3175]]

President's priorities, or the principles set forth in the Executive 
Order.
    It has been determined that this proposed rule is not a 
``significant regulatory action'' within the meaning of the Executive 
Order and is therefore not subject to OMB review. These proposed 
changes to the HON are primarily technical and administrative and do 
not raise any novel legal or policy issues. These proposed changes are 
not expected to impose significant new costs. This proposed action will 
not have an annual effect on the economy of $100 million or other 
adverse economic impacts, not create any inconsistencies with other 
actions by other agencies, not alter any budgetary impacts, or raise 
any novel legal or policy issues.

B. Executive Order 13084: Consultation and Coordination with Indian 
Tribal Governments

    Under Executive Order 13084, the EPA may not issue a regulation 
that is not required by statute, that significantly or uniquely affects 
the communities of Indian tribal governments, and that imposes 
substantial direct compliance costs on those communities, unless the 
Federal government provides the funds necessary to pay the direct 
compliance costs incurred by the tribal governments, or EPA consults 
with those governments. If EPA complies by consulting, Executive Order 
13084 requires EPA to provide to the OMB, in a separately identified 
section of the preamble to the rule, a description of the extent of 
EPA's prior consultation with representatives of affected tribal 
governments, a summary of the nature of their concerns, and a statement 
supporting the need to issue the regulation. In addition, Executive 
Order 13084 requires EPA to develop an effective process permitting 
elected officials and other representatives of Indian tribal 
governments ``to provide meaningful and timely input in the development 
of regulatory policies on matters that significantly or uniquely affect 
their communities.''
    Today's proposed amendments to the rule would not significantly or 
uniquely affect the communities of Indian tribal governments. The 
proposal would amend the definition of ``process vent'' and would make 
other technical and administrative changes to the rule. Accordingly, 
the requirements of section 3(b) of Executive Order 13084 do not apply 
to this proposed rule.

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

    Executive Order 13045, ``Protection of Children from Environmental 
Health Risks and Safety Risks'' (62 FR 19885, April 23, 1997), applies 
to any rule that: (1) is determined to be ``economically significant'' 
as defined under Executive Order 12866, and (2) concerns an 
environmental health or safety risk that the EPA has reason to believe 
may have a disproportionate effect on children. If the regulatory 
action meets both criteria, the EPA must evaluate the environmental 
health or safety effects of the planned rule on children, and explain 
why the planned regulation is preferable to other potentially effective 
and reasonably feasible alternatives considered by the Agency.
    The EPA interprets Executive Order 13045 as applying only to those 
regulatory actions that are based on health or safety risks, such that 
the analysis required under section 5-501 of the Executive Order has 
the potential to influence the regulation. This action is not subject 
to Executive Order 13045 because it is based on technology performance 
and not on health or safety risks.

D. Executive Order 13132 on Federalism

    Executive Order 13132, entitled ``Federalism'' (64 FR 43255, August 
10, 1999), requires EPA to develop an accountable process to ensure 
``meaningful and timely input by State and local officials in the 
development of regulatory policies that have federalism implications.'' 
``Policies that have federalism implications'' is defined in the 
Executive Order to include regulations that have ``substantial direct 
effects on the States, on the relationship between the national 
government and the States, or on the distribution of power and 
responsibilities among the various levels of government.'' Under 
Executive Order 13132, EPA may not issue a regulation that has 
federalism implications, that imposes substantial direct compliance 
costs, and that is not required by statute, unless the Federal 
government provides the funds necessary to pay the direct compliance 
costs incurred by State and local governments, or EPA consults with 
State and local officials early in the process of developing the 
proposed regulation. The EPA also may not issue a regulation that has 
federalism implications and that preempts State law unless the Agency 
consults with State and local officials early in the process of 
developing the proposed regulation.
    If EPA complies by consulting, Executive Order 13132 requires EPA 
to provide to OMB, in a separately identified section of the preamble 
to the rule, a federalism summary impact statement (FSIS). The FSIS 
must include a description of the extent of EPA's prior consultation 
with State and local officials, a summary of the nature of their 
concerns, and the Agency's position supporting the need to issue the 
regulation, and a statement of the extent to which the concerns of 
State and local officials have been met. Also, when EPA transmits a 
draft final rule with federalism implications to OMB for review 
pursuant to Executive Order 12866, EPA must include a certification 
from the Agency's Federalism Official stating that EPA has met the 
requirements of Executive Order 13132 in a meaningful and timely 
manner.
    These proposed amendments to the final rule will not have 
substantial direct effects on the States, on the relationship between 
the national government and the States, or on the distribution of power 
and responsibilities among the various levels of government, as 
specified in Executive Order 13132. Today's proposed amendments would 
not impose any enforceable duties on these entities. The proposal would 
amend the definition of ``process vent'' and would make other technical 
and administrative changes to the rule. Thus, the requirements of 
section 6 of the Executive Order do not apply to these proposed 
amendments to the final rule.

E. Unfunded Mandates Reform Act

    Title II of the Unfunded Mandates Reform Act of 1995 (UMRA), Public 
Law 104-4, establishes requirements for Federal agencies to assess the 
effects of their regulatory actions on State, local, and tribal 
governments and the private sector. Under section 202 of UMRA, the EPA 
generally must prepare a written statement, including a cost-benefit 
analysis, for proposed or final rules with ``Federal mandates'' that 
may result in estimated costs to State, local, or tribal governments in 
the aggregate, or to the private sector, of $100 million or more in any 
1 year. Before promulgating an EPA rule for which a written statement 
is needed, section 205 of the UMRA generally requires the EPA to 
identify and consider a reasonable number of regulatory alternatives 
and adopt the least costly, most cost-effective, or least burdensome 
alternative that achieves the objectives of the rule. The provisions of 
section 205 do not apply when they are inconsistent with applicable 
law. Moreover, section 205 allows the EPA to adopt an alternative

[[Page 3176]]

other than the least costly, most cost-effective, or least burdensome 
alternative if the Administrator publishes with the final rule an 
explanation why that alternative was not adopted. Before the EPA 
establishes any regulatory requirements that may significantly or 
uniquely affect small governments, including tribal governments, it 
must have developed under section 203 of the UMRA a small government 
agency plan. The plan must provide for notifying potentially affected 
small governments, enabling officials of affected small governments to 
have meaningful and timely input in the development of EPA regulatory 
proposals with significant Federal intergovernmental mandates, and 
informing, educating, and advising small governments on compliance with 
the regulatory requirements.
    The EPA has determined that today's proposed action does not 
contain a Federal mandate that may result in estimated costs of $100 
million or more to either State, local, or tribal governments in the 
aggregate or to the private sector in any 1 year. Therefore, the 
requirements of sections 202 and 205 of the UMRA do not apply to this 
action. The EPA has likewise determined that the action proposed today 
does not include any regulatory requirements that might significantly 
or uniquely affect small governments. Thus, today's action is not 
subject to the requirements of section 203 of the UMRA.

F. Regulatory Flexibility/Small Business Regulatory Enforcement 
Fairness Act of 1996

    The Regulatory Flexibility Act of 1980 (RFA) (5 U.S.C. 601, et 
seq.), as amended by the Small Business Regulatory Enforcement Fairness 
Act of 1996 (SBREFA), requires the EPA to give special consideration to 
the effect of Federal regulations on small entities and to consider 
regulatory options that might mitigate any such impacts. The EPA is 
required to prepare a regulatory flexibility analysis and coordinate 
with small entity stakeholders if the Agency determines that a rule 
will have a significant economic impact on a substantial number of 
small entities.
    The EPA has determined that it is not necessary to prepare a 
regulatory flexibility analysis in connection with these proposed 
amendments to the rule. The EPA has also determined that these 
amendments will not have a significant economic impact on a substantial 
number of small entities. Small entities include small businesses, 
small not-for-profit enterprises, and small government jurisdictions. 
See the April 22, 1994 Federal Register (59 FR 19449) for the basis for 
this determination. The proposed changes are primarily technical and 
administrative, and are not expected to impose significant new costs. 
The EPA does not anticipate that the proposed changes will create any 
significant additional burden for any of the regulated entities.

G. Paperwork Reduction Act

    The OMB has approved the information collection requirements 
contained in the rule under the provisions of the Paperwork Reduction 
Act, 44 U.S.C. 3501, et seq., and has assigned OMB control number 2060-
0282. An Information Collection Request (ICR) document was prepared by 
the EPA (ICR No. 1414.03) and a copy may be obtained from Sandy Farmer, 
OP Regulatory Information Division, U.S. Environmental Protection 
Agency (2137), 401 M St. SW, Washington, DC 20460 or by calling (202) 
260-2740.
    An agency may not conduct or sponsor, and a person is not required 
to respond to an information collection request unless it displays a 
currently valid OMB control number. The OMB control numbers for the 
EPA's regulations are listed in 40 CFR part 9 and 48 CFR chapter 15.
    Today's proposed amendments to the rule should have a very minor 
effect on the information collection burden estimates made previously. 
Based on discussions with industry representatives, EPA believes that 
this action would result in less than a 2 percent increase in the 
estimated information collection burden. This potential increase would 
include the burden associated with identification of and submittal of 
compliance documentation for previously unreported process vents 
subject to this rule. The potential increase would also include the 
burden associated with preparation of a supplemental report to identify 
the point of origination of the reported process vents as well as the 
discharge point. The EPA also estimates that a small (less than 2 
percent) number of facilities may be required to install controls as a 
result of today's proposed changes. The EPA considers these changes to 
the rule to represent a clarification of the definition of process vent 
and the reporting requirements for process vents. Thus, EPA considers 
these potential increases in the burden estimate to be well within the 
uncertainty of the analysis. Consequently, the ICR has not been revised 
for these proposed amendments to the rule.

H. National Technology Transfer and Advancement Act

    Section 12(d) of the National Technology Transfer and Advancement 
Act of 1995 (NTTAA), Pub. L. No. 104- 113, Sec. 12(d) (15 U.S.C. 272 
note), directs the EPA to use voluntary consensus standards in its 
regulatory activities unless to do so would be inconsistent with 
applicable law or otherwise impractical. Voluntary consensus standards 
are technical standards (e.g., materials specifications, test methods, 
sampling procedures, business practices, etc.) that are developed or 
adopted by voluntary consensus standard bodies. The NTTAA directs the 
EPA to provide Congress, through OMB, explanations when the Agency 
decides not to use available and applicable voluntary consensus 
standards.
    This proposed action includes amendments to appendix C to add 
another procedure for determining fraction biodegraded. Therefore, we 
conducted a search to identify potentially applicable voluntary 
consensus standards for this case. However, we identified no such 
standards. Therefore, EPA proposes to add this additional procedure to 
appendix C. The EPA welcomes comments on this aspect of the proposed 
rulemaking and, specifically, invites the public to identify 
potentially-applicable voluntary consensus standards and to explain why 
such standards should be used in this regulation.
    In the event commenters identify potentially-applicable voluntary 
consensus standards, EPA will carefully evaluate whether these 
procedures are viable alternatives to the proposed procedure. However, 
EPA does not anticipate that there will be any standards identified 
that are equivalent in terms of stringency and other criteria.

List of Subjects in 40 CFR Part 63

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

    Dated: January 10, 2000.
Carol M. Browner,
Administrator.
    For the reasons set out in the preamble, title 40 chapter I, part 
63 of the Code of Federal Regulations is proposed to be amended as 
follows:

PART 63--[AMENDED]

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

    Authority:  42 U.S.C. 7401, et seq.

[[Page 3177]]

Subpart F--National Emission Standards for Organic Hazardous Air 
Pollutants From the Synthetic Organic Chemical Manufacturing 
Industry

    2. Section 63.100 is amended by revising paragraph (e) introductory 
text, by revising paragraph (j)(4), and by adding paragraph (q) to read 
as follows:


Sec. 63.100  Applicability and designation of source.

* * * * *
    (e) The source to which this subpart applies is the collection of 
all chemical manufacturing process units and the associated equipment 
at a major source that meet the criteria specified in paragraphs (b)(1) 
through (b)(3) of this section. The source includes the process vents; 
storage vessels; transfer racks; waste management units; maintenance 
wastewater; heat exchange systems; equipment identified in Sec. 63.149; 
and pumps, compressors, agitators, pressure relief devices, sampling 
connection systems, open-ended valves or lines, valves, connectors, 
instrumentation systems, surge control vessels, and bottoms receivers 
that are associated with that collection of chemical manufacturing 
process units. The source also includes equipment required by, or 
utilized as a method of compliance with, subparts F, G, or H of this 
part which may include control devices and recovery devices.
* * * * *
    (j) * * *
    (4) Batch process vents within a chemical manufacturing process 
unit.
* * * * *
    (q) If the owner or operator of a process vent, or of a gas stream 
transferred subject to Sec. 63.113(i), is unable to comply with the 
provisions of Secs. 63.113 through 63.118 by the applicable compliance 
date specified in paragraph (k),(l), or (m) of this section for the 
reasons stated in paragraph (q)(1),(q)(3), or (q)(5) of this section, 
the owner or operator shall comply with the applicable provisions in 
Secs. 63.113 through 63.118 as expeditiously as practicable, but in no 
event later than the date approved by the Administrator pursuant to 
paragraph (q)(2), (q)(4), or (q)(6) of this section, respectively. For 
requests under paragraph (q)(1) or (q)(3) of this section, the date 
approved by the Administrator may be earlier than, and shall not be 
later than, the later of [DATE 3 YEARS AFTER DATE OF PUBLICATION OF 
FINAL RULE IN THE Federal Register] or 3 years after the transferee's 
refusal to accept the stream for disposal. For requests submitted under 
paragraph (q)(5) of this section, the date approved by the 
Administrator may be earlier than, and shall not be later than, 3 years 
after the date of promulgation of the amendments to this subpart or to 
subpart G of part 63 which created the need for an extension of the 
compliance.
    (1) If the owner or operator has been sending a gas stream for 
disposal as described in Sec. 63.113(i) prior to [DATE OF PUBLICATION 
OF FINAL RULE IN THE Federal Register], and the transferee does not 
submit a written certification as described in Sec. 63.113(i)(2) and 
ceases to accept the gas stream for disposal, the owner or operator 
shall comply with paragraph (q)(2) of this section.
    (2)(i) An owner or operator directed to comply with paragraph 
(q)(2) of this section shall submit to the Administrator for approval a 
compliance schedule, along with a justification for the schedule.
    (ii) The compliance schedule and justification shall be submitted 
no later than 90 days after the transferee ceases to accept the gas 
stream for disposal.
    (iii) The Administrator shall approve the compliance schedule or 
request changes within 120 days of receipt of the compliance schedule 
and justification.
    (3) If the owner or operator has been sending the gas stream for 
disposal as described in Sec. 63.113(i) to a transferee who had 
submitted a written certification as described in Sec. 63.113(i)(2), 
and the transferee revokes its written certification, the owner or 
operator shall comply with paragraph (q)(4) of this section. During the 
period between the date when the owner or operator receives notice of 
revocation of the transferee's written certification and the compliance 
date established under paragraph (q)(4) of this section, the owner or 
operator shall implement, to the extent reasonably available, measures 
to prevent or minimize excess emissions to the extent practical. For 
purposes of this paragraph (q)(3) of this section, the term ``excess 
emissions'' means emissions in excess of those that would have occurred 
if the transferee had continued managing the gas stream in compliance 
with the requirements in Secs. 63.113 through 63.118. The measures to 
be taken shall be identified in the applicable start-up, shutdown, and 
malfunction plan. If the measures that can be reasonably taken will 
change over time, so that a more effective measure which could not 
reasonably be taken initially would be reasonable at a later date, the 
Administrator may require the more effective measure by a specified 
date (in addition to or instead of any other measures taken sooner or 
later than that date) as a condition of approval of the compliance 
schedule.
    (4)(i) An owner or operator directed to comply with paragraph 
(q)(4) of this section shall submit to the Administrator for approval 
the documents specified in paragraphs (q)(4)(i)(A) through (E) of this 
section no later than 90 days after the owner or operator receives 
notice of revocation of the transferee's written certification.
    (A) A request for determination of a compliance date.
    (B) A justification for the request for determination of a 
compliance date.
    (C) A compliance schedule.
    (D) A justification for the compliance schedule.
    (E) A description of the measures that will be taken to minimize 
excess emissions until the new compliance date, and the date when each 
measure will first be implemented. The owner or operator shall describe 
how, and to what extent, each measure will minimize excess emissions, 
and shall justify any period of time when measures are not in place.
    (ii) The Administrator shall approve or disapprove the request for 
determination of a compliance date and the compliance schedule, or 
request changes, within 120 days after receipt of the documents 
specified in paragraphs (q)(4)(i)(A) through (E) of this section. Upon 
approving the request for determination and compliance schedule, the 
Administrator shall specify a reasonable compliance date consistent 
with the introductory text in paragraph (q) of this section.
    (5) If the owner's or operator's inability to meet otherwise 
applicable compliance deadlines is due to amendments of this subpart or 
of subpart G of part 63 promulgated on or after [DATE OF PUBLICATION OF 
FINAL RULE IN THE Federal Register] and neither condition specified in 
paragraph (q)(1) or (q)(3) of this section is applicable, the owner or 
operator shall comply with paragraph (q)(6) of this section.
    (6)(i) An owner or operator directed to comply with this paragraph 
shall submit to the Administrator for approval a request for 
determination of a compliance date, a compliance schedule, a 
justification for the determination of a compliance date, and a 
justification for the compliance schedule.
    (ii) The documents required to be submitted under paragraph 
(q)(6)(i) of this section shall be submitted no later than 120 days 
after publication of the amendments of this subpart or of subpart G of 
part 63 which necessitate the request for an extension.

[[Page 3178]]

    (iii) The Administrator shall approve or disapprove the request for 
a determination of a compliance date, or request changes, within 120 
days after receipt of the request for determination of a compliance 
date, the compliance schedule, and the two justifications. If the 
request for determination of a compliance date is disapproved, the 
compliance schedule is disapproved and the owner or operator shall 
comply by the applicable date specified in paragraph (k),(l), or (m) of 
this section. If the request for the determination of a compliance date 
is approved, the Administrator shall specify, at the time of approval, 
a reasonable compliance date consistent with the introductory text in 
paragraph (q) of this section.
    3. Section 63.101 is amended by adding in alphabetical order the 
definition of ``Batch process vent'' and by revising the definition of 
``Process vent'' to read as follows:


Sec. 63.101  Definitions.

* * * * *
    Batch process vent means gaseous venting to the atmosphere from a 
batch operation.
* * * * *
    Process vent means the point of discharge to the atmosphere (or the 
point of entry into a control device, if any) of a gas stream if the 
gas stream has the characteristics specified in Sec. 63.107(b) through 
(h) or meets the criteria specified in Sec. 63.107(i). For purposes of 
Secs. 63.113 through 63.118, all references to the characteristics of a 
process vent (e.g., flow rate, total HAP concentration, or TRE index 
value) shall mean the characteristics of the gas stream.
* * * * *
    4. Subpart F is amended by adding a new Sec. 63.107 to read as 
follows:


Sec. 63.107  Identification of Process Vents Subject to this Subpart.

    (a) The owner or operator shall use the criteria specified in this 
section to determine whether there are any process vents associated 
with an air oxidation reactor, distillation unit, or reactor that is in 
a source subject to this subpart. A process vent is the point of 
discharge to the atmosphere (or the point of entry into a control 
device, if any) of a gas stream if the gas stream has the 
characteristics specified in paragraphs (b) through (h) of this section 
or meets the criteria specified in paragraph (i) of this section.
    (b) Some, or all, of the gas stream originates as a continuous flow 
from an air oxidation reactor, distillation unit, or reactor during 
operation of the chemical manufacturing process unit.
    (c) The discharge to the atmosphere (with or without passing 
through a control device) meets at least one of the conditions 
specified in paragraphs (c)(1) through (c)(3) of this section.
    (1) Is directly from an air oxidation reactor, distillation unit, 
or reactor; or
    (2) Is from an air oxidation reactor, distillation unit, or reactor 
after passing solely (i.e., without passing through any other unit 
operation for a process purpose) through one or more recovery devices 
within the chemical manufacturing process unit; or
    (3) Is from a device recovering only mechanical energy from a gas 
stream that comes either directly from an air oxidation reactor, 
distillation unit, or reactor, or from an air oxidation reactor, 
distillation unit, or reactor after passing solely (i.e., without 
passing through any other unit operation for a process purpose) through 
one or more recovery devices within the chemical manufacturing process 
unit.
    (d) The gas stream contains greater than 0.005 weight percent total 
organic hazardous air pollutants at the point of discharge to the 
atmosphere (or at the point of entry into a control device, if any).
    (e) The air oxidation reactor, distillation unit, or reactor is 
part of a chemical manufacturing process unit that meets the criteria 
of Sec. 63.100(b).
    (f) The gas stream is in the gas phase from the point of origin at 
the air oxidation reactor, distillation unit, or reactor to the point 
of discharge to the atmosphere (or to the point of entry into a control 
device, if any).
    (g) The gas stream is discharged to the atmosphere either on-site, 
off-site, or both.
    (h) The gas stream is not any of the items identified in paragraphs 
(h)(1) through (h)(9) of this section.
    (1) A relief valve discharge.
    (2) A leak from equipment subject to subpart H of this part.
    (3) A gas stream going to a fuel gas system as defined in 
Sec. 63.101.
    (4) A gas stream exiting a control device used to comply with 
Sec. 63.113.
    (5) A gas stream transferred to other processes (on-site or off-
site) for reaction or other use in another process (i.e., for chemical 
value as a product, isolated intermediate, byproduct, or coproduct or 
for heat value).
    (6) A gas stream transferred for fuel value (i.e., net positive 
heating value), use, reuse, or for sale for fuel value, use, or reuse.
    (7) A storage vessel vent or transfer operation vent subject to 
Sec. 63.119 or Sec. 63.126.
    (8) A vent from a waste management unit subject to Secs. 63.132 
through 63.137.
    (9) A gas stream exiting a process analyzer.
    (i) The gas stream would meet the characteristics specified in 
paragraphs (b) through (g) of this section, but, for purposes of 
avoiding applicability, has been deliberately interrupted, temporarily 
liquefied, routed through any item of equipment for no process purpose, 
or disposed of in a flare that does not meet the criteria in 
Sec. 63.11(b), or an incinerator that does not reduce emissions of 
organic hazardous air pollutants by 98 percent or to a concentration of 
20 ppm by volume, whichever is less stringent.

Subpart G--National Emission Standards for Organic Hazardous Air 
Pollutants from Synthetic Organic Chemical Manufacturing Industry 
for Process Vents, Storage Vessels, Transfer Operations, and 
Wastewater

    5. Section 63.110 is amended by revising paragraph (a) to read as 
follows:


Sec. 63.110  Applicability.

    (a) This subpart applies to all process vents, storage vessels, 
transfer racks, wastewater streams, and/or in-process equipment subject 
to Sec. 63.149 within a source subject to subpart F of this part.
* * * * *
    6. Section 63.111 is amended by adding in alphabetical order the 
definition of ``Point of transfer'' and by revising the definitions of 
``Group 1 process vent,'' ``Group 2 process vent,'' and ``Vent stream'' 
to read as follows:


Sec. 63.111  Definitions.

* * * * *
    Group 1 process vent means a process vent for which the vent stream 
flow rate is greater than or equal to 0.005 standard cubic meter per 
minute, the total organic HAP concentration is greater than or equal to 
50 ppm by volume, and the total resource effectiveness index value, 
calculated according to Sec. 63.115, is less than or equal to 1.0.
    Group 2 process vent means a process vent for which the vent stream 
flow rate is less than 0.005 standard cubic meter per minute, the total 
organic HAP concentration is less than 50 ppm by volume or the total 
resource effectiveness index value, calculated according to 
Sec. 63.115, is greater than 1.0.
* * * * *
    Point of transfer means:
    (1) If the transfer is to an off-site location for control, the 
point where the conveyance crosses the property line; or
    (2) If the transfer is to an on-site location not owned or operated 
by the

[[Page 3179]]

owner or operator of the source, the point where the conveyance enters 
the operation or equipment of the transferee.
* * * * *
    Vent stream, as used in the process vent provisions, means the gas 
stream flowing through the process vent.
* * * * *
    7. Section 63.113 is amended by:
    a. Revising paragraph (a) introductory text.
    b. Revising the second sentence in paragraph (a)(3).
    c. Revising paragraph (c) introductory text and paragraph (c)(1) 
introductory text.
    d. Revising paragraphs (e) and (g).
    e. Adding a new paragraph (i).
    The revisions and addition read as follows:


Sec. 63.113  Process vent provisions--reference control technology.

    (a) The owner or operator of a Group 1 process vent as defined in 
this subpart shall comply with the requirements of paragraph (a)(1), 
(a)(2), or (a)(3) of this section. The owner or operator who transfers 
a gas stream that has the characteristics specified in Sec. 63.107 (b) 
through (h) or meets the criteria specified in Sec. 63.107(i) to an 
off-site location or an on-site location not owned or operated by the 
owner or operator of the source for disposal shall comply with the 
requirements of paragraph (i) of this section.
* * * * *
    (3) * * * If the TRE index value is greater than 1.0, the process 
vent shall comply with the provisions for a Group 2 process vent 
specified in either paragraph (d) or (e) of this section, whichever is 
applicable.
* * * * *
    (c) Halogenated vent streams from Group 1 process vents that are 
combusted shall be controlled according to paragraph (c)(1) or (c)(2) 
of this section.
    (1) If a combustion device is used to comply with paragraph (a)(2) 
of this section for a halogenated vent stream, then the gas stream 
exiting the combustion device shall be conveyed to a halogen reduction 
device, such as a scrubber, before it is discharged to the atmosphere.
* * * * *
    (e) The owner or operator of a Group 2 process vent with a TRE 
index value greater than 4.0 shall maintain a TRE index value greater 
than 4.0, comply with the provisions for calculation of TRE index in 
Sec. 63.115 and the reporting and recordkeeping provisions in 
Sec. 63.117(b), Sec. 63.118(c), and Sec. 63.118(h), and is not subject 
to monitoring or any other provisions of Secs. 63.114 through 63.118.
* * * * *
    (g) The owner or operator of a Group 2 process vent with a total 
organic HAP concentration less than 50 ppm by volume shall maintain a 
total organic HAP concentration less than 50 ppm by volume; comply with 
the Group determination procedures in Sec. 63.115(a), (c), and (e); the 
reporting and recordkeeping requirements in Sec. 63.117(d), 
Sec. 63.118(e), and Sec. 63.118(j); and is not subject to monitoring or 
any other provisions of Secs. 63.114 through 63.118.
* * * * *
    (i) Off-site control or on-site control not owned or operated by 
the source. This paragraph applies to gas streams that have the 
characteristics specified in Secs. 63.107(b) through (h) of subpart F 
of this part or meet the criteria specified in Sec. 63.107(i) of 
subpart F of this part; that are transferred for disposal to an on-site 
control device (or other compliance equipment) not owned or operated by 
the owner or operator of the source generating the gas stream, or to an 
off-site control device or other compliance equipment; and that have 
the characteristics (e.g., flow rate, total organic HAP concentration, 
or TRE index value) of a Group 1 process vent, determined at the point 
of transfer.
    (1) The owner or operator transferring the gas stream shall:
    (i) Comply with the provisions specified in Sec. 63.114(d) for each 
gas stream prior to transfer.
    (ii) Notify the transferee that the gas stream contains organic 
hazardous air pollutants that are to be treated in accordance with the 
provisions of this subpart. The notice shall be submitted to the 
transferee initially and whenever there is a change in the required 
control.
    (2) The owner or operator may not transfer the gas stream unless 
the transferee has submitted to the EPA a written certification that 
the transferee will manage and treat any gas stream transferred under 
this paragraph (i) of this section and received from a source subject 
to the requirements of this subpart in accordance with the requirements 
of either Secs. 63.113 through 63.118, or Sec. 63.102(b), or subpart D 
of this part if alternative emission limitations have been granted the 
transferor in accordance with those provisions. The certifying entity 
may revoke the written certification by sending a written statement to 
the EPA and the owner or operator giving at least 90 days notice that 
the certifying entity is rescinding acceptance of responsibility for 
compliance with the regulatory provisions listed in this paragraph. 
Upon expiration of the notice period, the owner or operator may not 
transfer the gas stream to the transferee. Records retained by the 
transferee shall be retained in accordance with Sec. 63.10(b).
    (3) By providing this written certification to the EPA, the 
certifying entity accepts responsibility for compliance with the 
regulatory provisions listed in paragraph (i)(2) of this section with 
respect to any transfer covered by the written certification. Failure 
to abide by any of those provisions with respect to such transfers may 
result in enforcement action by the EPA against the certifying entity 
in accordance with the enforcement provisions applicable to violations 
of these provisions by owners or operators of sources.
    (4) Written certifications and revocation statements to the EPA 
from the transferees of such gas streams shall be signed by a 
responsible official of the certifying entity, provide the name and 
address of the certifying entity, and be sent to the appropriate EPA 
Regional Office at the addresses listed in 40 CFR 63.13. Such written 
certifications are not transferable by the transferee.
    8. Section 63.114 is amended by revising paragraphs (a)(3), 
(a)(4)(ii), and (d) to read as follows:


Sec. 63.114  Process vent provisions--monitoring requirements.

    (a) * * *
    (3) Where a boiler or process heater of less than 44 megawatts 
design heat input capacity is used, the following monitoring equipment 
is required: a temperature monitoring device in the firebox equipped 
with a continuous recorder. This requirement does not apply to gas 
streams that are introduced with primary fuel or are used as the 
primary fuel.
    (4) * * *
    (ii) A flow meter equipped with a continuous recorder shall be 
located at the scrubber influent for liquid flow. Gas flow rate shall 
be determined using one of the procedures specified in paragraphs 
(a)(4)(ii)(A) through (C) of this section.
    (A) The owner or operator may determine gas flow rate using the 
design blower capacity, with appropriate adjustments for pressure drop.
    (B) If the scrubber is subject to regulations in 40 CFR parts 264 
through 266 that have required a determination of the liquid to gas (L/
G) ratio prior to the applicable compliance date for this subpart 
specified in Sec. 63.100(k), the owner or operator may determine gas

[[Page 3180]]

flow rate by the method that had been utilized to comply with those 
regulations. A determination that was conducted prior to the compliance 
date for this subpart may be utilized to comply with this subpart if it 
is still representative.
    (C) The owner or operator may prepare and implement a gas flow rate 
determination plan that documents an appropriate method which will be 
used to determine the gas flow rate. The plan shall require 
determination of gas flow rate by a method which will at least provide 
a value for either a representative or the highest gas flow rate 
anticipated in the scrubber during representative operating conditions 
other than start-ups, shutdowns, or malfunctions. The plan shall 
include a description of the methodology to be followed and an 
explanation of how the selected methodology will reliably determine the 
gas flow rate, and a description of the records that will be maintained 
to document the determination of gas flow rate. The owner or operator 
shall maintain the plan as specified in Sec. 63.103(c).
* * * * *
    (d) The owner or operator of a process vent shall comply with 
paragraph (d)(1) or (d)(2) of this section for any bypass line, between 
the origin of the gas stream (i.e., at an air oxidation reactor, 
distillation unit, or reactor as identified in Sec. 63.107(b)) and the 
point where the gas stream reaches the process vent as described in 
Sec. 63.107, that could divert the gas stream directly to the 
atmosphere. Equipment such as low leg drains, high point bleeds, 
analyzer vents, open-ended valves or lines, and pressure relief valves 
needed for safety purposes are not subject to this paragraph.
    (1) Properly install, maintain, and operate a flow indicator that 
takes a reading at least once every 15 minutes. Records shall be 
generated as specified in Sec. 63.118(a)(3). The flow indicator shall 
be installed at the entrance to any bypass line that could divert the 
gas stream to the atmosphere; or
    (2) Secure the bypass line valve in the non-diverting position with 
a car-seal or a lock-and-key type configuration. A visual inspection of 
the seal or closure mechanism shall be performed at least once every 
month to ensure that the valve is maintained in the non-diverting 
position and the gas stream is not diverted through the bypass line.
* * * * *
    9. Section 63.115 is amended by:
    a. Revising paragraph (a) introductory text.
    b. Revising paragraph (b) introductory text.
    c. Revising paragraph (c) introductory text,
    (c)(4)(i), and (c)(4)(ii).
    d. Revising paragraph (d)(1) introductory text and
    (d)(1)(iii)(D)(4).
    e. Revising paragraph (d)(2) introductory text, (d)(2)(i) and 
(d)(2)(ii) introductory text, and (d)(2)(ii)(C).
    f. Adding paragraph (f).
    The revisions and addition read as follows:


Sec. 63.115  Process vent provisions--methods and procedures for 
process vent group determination.

    (a) For purposes of determining vent stream flow rate, total 
organic HAP or TOC concentration or TRE index value, as specified under 
paragraph (b), (c), or (d) of this section, the sampling site shall be 
after the last recovery device (if any recovery devices are present) 
but prior to the inlet of any control device that is present and prior 
to release to the atmosphere.
* * * * *
    (b) To demonstrate that a vent stream flow rate is less than 0.005 
standard cubic meter per minute in accordance with the Group 2 process 
vent definition of this subpart, the owner or operator shall measure 
flow rate by the following procedures:
* * * * *
    (c) Each owner or operator seeking to demonstrate that a vent 
stream has an organic HAP concentration below 50 ppm by volume in 
accordance with the Group 2 process vent definition of this subpart 
shall measure either total organic HAP or TOC concentration using the 
following procedures:
* * * * *
    (4) * * *
    (i) Method 25A of 40 CFR part 60, appendix A shall be used only if 
a single organic HAP compound is greater than 50 percent of total 
organic HAP, by volume, in the vent stream.
    (ii) The vent stream composition may be determined by either 
process knowledge, test data collected using an appropriate EPA method, 
or a method or data validated according to the protocol in Method 301 
of appendix A of this part. Examples of information that could 
constitute process knowledge include calculations based on material 
balances, process stoichiometry, or previous test results provided the 
results are still relevant to the current vent stream conditions.
* * * * *
    (d) * * *
    (1) Engineering assessment may be used to determine vent stream 
flow rate, net heating value, TOC emission rate, and total organic HAP 
emission rate for the representative operating condition expected to 
yield the lowest TRE index value.
* * * * *
    (iii) * * *
    (D) * * *
    (4) Estimation of maximum expected net heating value based on the 
vent stream concentration of each organic compound or, alternatively, 
as if all TOC in the vent stream were the compound with the highest 
heating value.
* * * * *
    (2) Except as provided in paragraph (d)(1) of this section, vent 
stream flow rate, net heating value, TOC emission rate, and total 
organic HAP emission rate shall be measured and calculated according to 
the procedures in paragraphs (d)(2)(i) through (v) of this section and 
used as input to the TRE index value calculation in paragraph (d)(3) of 
this section.
    (i) The vent stream volumetric flow rate (Qs), in standard cubic 
meters per minute at 20  deg.C, shall be determined using Method 2, 2A, 
2C, or 2D of 40 CFR part 60, appendix A, as appropriate. If the vent 
stream tested passes through a final steam jet ejector and is not 
condensed, the vent stream volumetric flow shall be corrected to 2.3 
percent moisture.
    (ii) The molar composition of the vent stream, which is used to 
calculate net heating value, shall be determined using the following 
methods:
* * * * *
    (C) Method 4 of 40 CFR part 60, appendix A to measure the moisture 
content of the vent stream.
* * * * *
    (f) Notwithstanding any other provisions of this subpart, in any 
case where a process vent includes one or more gas streams that are not 
from a source subject to this subpart (hereafter called ``non-HON 
streams'' for purposes of this paragraph), and one or more gas streams 
that meet the criteria in Sec. 63.107(b) through (h) or the criteria in 
Sec. 63.107(i) (hereafter called ``HON streams'' for purposes of this 
paragraph), the owner or operator may elect to comply with paragraphs 
(f)(1) through (f)(3) of this section.
    (1) The owner or operator may determine the characteristics (flow 
rate, total organic HAP concentration, and TRE index value) for each 
HON stream, or combination of HON streams, at a representative point as 
near as practical to, but before, the point at which it is combined 
with non-HON streams.

[[Page 3181]]

    (2) If one or more of the HON streams, or combinations of HON 
streams, has the characteristics (determined at the location specified 
in paragraph (f)(1) of this section) associated with a Group 1 process 
vent, the combined vent stream is a Group 1 process vent. Except as 
specified in paragraph (f)(3) of this section, if none of the HON 
streams, or combinations of HON streams, when determined at the 
location specified in paragraph (f)(1) of this section has the 
characteristics associated with a Group 1 process vent, the combined 
vent stream is a Group 2 process vent regardless of the TRE index value 
determined at the location specified in Sec. 63.115(a). If the combined 
vent stream is a Group 2 process vent as determined by the previous 
sentence, but one or more of the HON streams, or combinations of HON 
streams, has a TRE index value greater than 1 but less than or equal to 
4, the combined vent stream is a process vent with a TRE index value 
greater than 1 but less than or equal to 4. In this case, the owner or 
operator shall monitor the combined vent stream as required by 
Sec. 63.114(b).
    (3) Paragraphs (f)(1) and (f)(2) of this section are not intended 
to apply instead of any other subpart of part 63. If another subpart of 
part 63 applies to one or more of the non-HON streams contributing to 
the combined vent stream, that subpart may impose emission control 
requirements such as, but not limited to, requiring the combined vent 
stream to be classified and controlled as a Group 1 process vent.
    10. Section 63.116 is amended by:
    a. Revising paragraph (a).
    b. Revising paragraph (b)(2).
    c. Revising paragraphs (c)(1)(i)(B) and (c)(4)(iv).
    d. Revising paragraph (d) introductory text.
    The revisions read as follows:


Sec. 63.116  Process vent provisions--performance test methods and 
procedures to determine compliance.

    (a) When a flare is used to comply with Sec. 63.113(a)(1), the 
owner or operator shall comply with paragraphs (a)(1) through (3) of 
this section. The owner or operator is not required to conduct a 
performance test to determine percent emission reduction or outlet 
organic HAP or TOC concentration.
    (1) Conduct a visible emission test using the techniques specified 
in Sec. 63.11(b)(4).
    (2) Determine the net heating value of the gas being combusted 
using the techniques specified in Sec. 63.11(b)(6).
    (3) Determine the exit velocity using the techniques specified in 
either Sec. 63.11(b)(7)(i) (and Sec. 63.11(b)(7)(iii), where 
applicable) or Sec. 63.11(b)(8), as appropriate.
    (b) * * *
    (2) A boiler or process heater into which the gas stream is 
introduced with the primary fuel or is used as the primary fuel.
* * * * *
    (c) * * *
    (1) * * *
    (i) * * *
    (B) If a vent stream is introduced with the combustion air or as a 
secondary fuel into a boiler or process heater with a design capacity 
less than 44 megawatts, selection of the location of the inlet sampling 
sites shall ensure the measurement of total organic HAP or TOC (minus 
methane and ethane) concentrations in all vent streams and primary and 
secondary fuels introduced into the boiler or process heater.
* * * * *
    (4) * * *
    (iv) If the vent stream entering a boiler or process heater with a 
design capacity less than 44 megawatts is introduced with the 
combustion air or as a secondary fuel, the weight-percent reduction of 
total organic HAP or TOC (minus methane and ethane) across the device 
shall be determined by comparing the TOC (minus methane and ethane) or 
total organic HAP in all combusted vent streams and primary and 
secondary fuels with the TOC (minus methane and ethane) or total 
organic HAP exiting the combustion device, respectively.
    (d) An owner or operator using a combustion device followed by a 
scrubber or other halogen reduction device to control halogenated vent 
streams in compliance with Sec. 63.113(c)(1) shall conduct a 
performance test to determine compliance with the control efficiency or 
emission limits for hydrogen halides and halogens.
* * * * *
    11. Section 63.117 is amended by revising paragraphs (a) 
introductory text, (a)(4)(iv), (a)(6) introductory text, and (a)(8) to 
read as follows:


Sec. 63.117  Process vents provisions--reporting and recordkeeping 
requirements for group and TRE determinations and performance tests.

    (a) Each owner or operator subject to the control provisions for 
Group 1 process vents in Sec. 63.113(a) or the provisions for Group 2 
process vents with a TRE index value greater than 1.0 but less than or 
equal to 4.0 in Sec. 63.113(d) shall:
* * * * *
    (4) * * *
    (iv) For a boiler or process heater with a design heat input 
capacity of less than 44 megawatts and where the vent stream is 
introduced with combustion air or used as a secondary fuel and is not 
mixed with the primary fuel, the percent reduction of organic HAP or 
TOC, or the concentration of organic HAP or TOC (ppm by volume, by 
compound) determined as specified in Sec. 63.116(c) at the outlet of 
the combustion device on a dry basis corrected to 3 percent oxygen.
* * * * *
    (6) Record and report the following when using a scrubber following 
a combustion device to control a halogenated vent stream:
* * * * *
    (8) Record and report the halogen concentration in the vent stream 
determined according to the procedures specified in 
Sec. 63.115(d)(2)(v).
* * * * *
    12. Section 63.118 is amended by revising paragraphs (a)(3), 
(e)(1), and (f)(3) to read as follows:


Sec. 63.118  Process vents provisions--Periodic reporting and 
recordkeeping requirements.

    (a) * * *
    (3) Hourly records of whether the flow indicator specified under 
Sec. 63.114(d)(1) was operating and whether a diversion was detected at 
any time during the hour, as well as records of the times and durations 
of all periods when the gas stream is diverted to the atmosphere or the 
monitor is not operating.
* * * * *
    (e) * * *
    (1) Any process changes as defined in Sec. 63.115(e) that increase 
the organic HAP concentration of the vent stream,
* * * * *
    (f) * * *
    (3) Reports of the times and durations of all periods recorded 
under paragraph (a)(3) of this section when the gas stream is diverted 
to the atmosphere through a bypass line.
* * * * *
    13. Section 63.128 is amended by revising paragraph (b) to read as 
follows:


Sec. 63.128  Transfer operations provisions--test methods and 
procedures.

* * * * *
    (b) When a flare is used to comply with Sec. 63.126(b)(2), the 
owner or operator shall comply with paragraphs (b)(1) through (3) of 
this section. The owner or operator is not required to conduct a 
performance test to determine percent emission reduction or outlet 
organic HAP or TOC concentration.

[[Page 3182]]

    (1) Conduct a visible emission test using the techniques specified 
in Sec. 63.11(b)(4). The observation period shall be as specified in 
paragraph (b)(1)(i) or (ii) of this section instead of the 2-hour 
period specified in Sec. 63.11(b)(4).
    (i) If the loading cycle is less than 2 hours, then the observation 
period for that run shall be for the entire loading cycle.
    (ii) If additional loading cycles are initiated within the 2-hour 
period, then visible emission observations shall be conducted for the 
additional cycles.
    (2) Determine the net heating value of the gas being combusted, 
using the techniques specified in Sec. 63.11(b)(6).
    (3) Determine the exit velocity using the techniques specified in 
either Sec. 63.11(b)(7)(i) (and Sec. 63.11(b)(7)(iii), where 
applicable) or Sec. 63.11(b)(8), as appropriate.
* * * * *
    14. Section 63.132 is amended by revising paragraphs (a)(3) and 
(b)(4) to read as follows:


Sec. 63.132  Process wastewater provisions--general.

    (a) * * *
    (3) Requirements for Group 2 wastewater streams. For wastewater 
streams that are Group 2 for table 9 compounds, comply with the 
applicable recordkeeping and reporting requirements specified in 
Secs. 63.146(b)(1) and 63.147(b)(8).
    (b) * * *
    (4) Requirements for Group 2 wastewater streams. For wastewater 
streams that are Group 2 for both table 8 and table 9 compounds, comply 
with the applicable recordkeeping and reporting requirements specified 
in Secs. 63.146(b)(1) and 63.147(b)(8).
* * * * *
    15. Section 63.138 is amended by:
    a. Revising paragraphs (i) introductory text and (i)(2)(iii);
    b. Adding a sentence to the end of paragraph (i)(1) introductory 
text and adding a sentence to the end of paragraph (i)(2)(i) 
introductory text;
    c. Amending paragraph (i)(2) introductory text by revising the 
reference ``(i)(2)(iv)'' to read ``(i)(3)''; and
    d. Redesignating paragraph (i)(2)(iv) as paragraph (i)(3).
    The revision additions read as follows:


Sec. 63.138  Process wastewater provisions--performance standards for 
treatment processes managing Group 1 wastewater streams and/or 
residuals removed from Group 1 wastewater streams.

* * * * *
    (i) One megagram total source mass flow rate option. A wastewater 
stream is exempt from the requirements of paragraphs (b) and (c) of 
this section if the owner or operator elects to comply with either 
paragraph (i)(1) or (i)(2) of this section, and complies with paragraph 
(i)(3) of this section.
    (1) * * * The owner or operator who meets the requirements of this 
paragraph (i)(1) of this section is exempt from the requirements of 
Secs. 63.133 through 63.137.
* * * * *
    (2) * * *
    (i) * * * When determining the total source mass flowrate for the 
purposes of paragraph (i)(2)(i)(B) of this section, the concentration 
and flow rate shall be determined at the location specified in 
paragraph (i)(2)(i)(B) of this section and not at the location 
specified in Sec. 63.144(b) and (c).
* * * * *
    (iii) The owner or operator of each waste management unit that 
receives, manages, or treats a partially treated wastewater stream 
prior to or during treatment shall comply with the requirements of 
Secs. 63.133 through 63.137, as applicable. For a partially treated 
wastewater stream that is stored, conveyed, treated, or managed in 
waste management unit meeting the requirements of Secs. 63.133 through 
63.137, the owner or operator shall follow the procedures in paragraph 
(i)(2)(i)(B) of this section to calculate mass flow rate. A wastewater 
stream, either untreated or partially treated, where the mass flow rate 
has been calculated following the procedures in paragraph (i)(2)(i)(A) 
of this section are exempt from the requirements of Secs. 63.133 
through 63.137.
* * * * *
    16. Section 63.145 is amended by revising paragraph (j) to read as 
follows:


Sec. 63.145  Process wastewater provisions--test methods and procedures 
to determine compliance.

* * * * *
    (j) When a flare is used to comply with Sec. 63.139(c), the owner 
or operator shall comply with paragraphs (j)(1) through (3) of this 
section. The owner or operator is not required to conduct a performance 
test to determine percent emission reduction or outlet organic HAP or 
TOC concentration.
    (1) Conduct a visible emission test using the techniques specified 
in Sec. 63.11(b)(4).
    (2) Determine the net heating value of the gas being combusted, 
using the techniques specified in Sec. 63.11(b)(6).
    (3) Determine the exit velocity using the techniques specified in 
either Sec. 63.11(b)(7)(i) (and Sec. 63.11(b)(7)(iii), where 
applicable) or Sec. 63.11(b)(8), as appropriate.
* * * * *
    17. Section 63.146 is amended by adding paragraph (b)(1) to read as 
follows:


Sec. 63.146  Process wastewater provisions--reporting.

* * * * *
    (b) * * *
    (1) Requirements for Group 2 wastewater streams. This paragraph 
does not apply to Group 2 wastewater streams that are used to comply 
with Sec. 63.138(g). For Group 2 wastewater streams, the owner or 
operator shall include the information specified in paragraphs 
(b)(1)(i) through (iv) of this section in the Notification of 
Compliance Status Report. This information may be submitted in any 
form. Table 15 of this subpart is an example.
    (i) Process unit identification and description of the process 
unit.
    (ii) Stream identification code.
    (iii) For existing sources, concentration of table 9 compound(s) in 
ppm, by weight. For new sources, concentration of table 8 and/or table 
9 compound(s) in ppm, by weight. Include documentation of the 
methodology used to determine concentration.
    (iv) Flow rate in liter per minute.
* * * * *
    18. Section 63.147 is amended by revising paragraphs (b) 
introductory text, (d) introductory text, and (d)(2), and by adding 
paragraphs (b)(8) and (d)(3) to read as follows:


Sec. 63.147  Process wastewater provisions--recordkeeping.

* * * * *
    (b) The owner or operator shall keep in a readily accessible 
location the records specified in paragraphs (b)(1) through (8) of the 
section.
* * * * *
    (8) Requirements for Group 2 wastewater streams. This paragraph 
(b)(8) of this section does not apply to Group 2 wastewater streams 
that are used to comply with Sec. 63.138(g). For all other Group 2 
wastewater streams, the owner or operator shall keep in a readily 
accessible location the records specified in paragraphs (b)(8)(i) 
through (iv) of this section in the Notification of Compliance Status 
Report.
    (i) Process unit identification and description of the process 
unit.
    (ii) Stream identification code.
    (iii) For existing sources, concentration of table 9 compound(s) in 
ppm, by weight. For new sources,

[[Page 3183]]

concentration of table 8 and/or table 9 compound(s) in ppm, by weight. 
Include documentation of the methodology used to determine 
concentration.
    (iv) Flow rate in liter per minute.
* * * * *
    (d) The owner or operator shall keep records of the daily average 
value of each continuously monitored parameter for each operating day 
as specified in Sec. 63.152(f), except as provided in paragraphs (d)(1) 
through (3) of this section.
* * * * *
    (2) Regenerative carbon adsorbers. For regenerative carbon 
adsorbers, the owner or operator shall keep the records specified in 
paragraphs (d)(2)(i) and (ii) of this section instead of daily 
averages.
    (i) Records of the total regeneration stream mass flow for each 
carbon bed regeneration cycle.
    (ii) Records of the temperature of the carbon bed after each 
regeneration cycle.
    (3) Non-regenerative carbon adsorbers. For non-regenerative carbon 
adsorbers using organic monitoring equipment, the owner or operator 
shall keep the records specified in paragraph (d)(3)(i) of this section 
instead of daily averages. For non-regenerative carbon adsorbers 
replacing the carbon adsorption system with fresh carbon at a regular 
predetermined time interval that is less than the carbon replacement 
interval that is determined by the maximum design flow rate and organic 
concentration in the gas stream vented to the carbon adsorption system, 
the owner or operator shall keep the records specified in paragraph 
(d)(3)(ii) of this section instead of daily averages.
    (i)(A) Record of how the monitoring frequency, as specified in 
table 13 of this subpart, was determined.
    (B) Records of when organic compound concentration of adsorber 
exhaust was monitored.
    (C) Records of when the carbon was replaced.
    (ii)(A) Record of how the carbon replacement interval, as specified 
in table 13 of this subpart, was determined.
    (B) Records of when the carbon was replaced.
* * * * *
    19. Section 63.151 is amended by revising paragraphs (b)(1)(iii) 
and (e)(1) to read as follows:


Sec. 63.151  Initial notification.

* * * * *
    (b) * * *
    (1) * * *
    (iii) An identification of the kinds of emission points within the 
source that are subject to this subpart;
* * * * *
    (e) * * *
    (1) A list designating each emission point complying with 
Secs. 63.113 through 63.149 and whether each emission point is Group 1 
or Group 2, as defined in Sec. 63.111. For each process vent within the 
source, provide the information listed in paragraphs (e)(1)(i) through 
(iv) of this section.
    (i) The chemical manufacturing process unit(s) that is the origin 
of all or part of the vent stream that exits the process vent.
    (ii) The type(s) of unit operations (i.e., an air oxidation 
reactor, distillation unit, or reactor) that creates the vent stream 
that exits the process vent.
    (iii) For a Group 2 process vent, the last recovery device, if any.
    (iv) For a Group 1 process vent, the control device, or other 
equipment used for compliance.
* * * * *
    20. Section 63.152 is amended by adding a new paragraph (b)(6), 
revising paragraph (c)(4)(iv), and adding a new paragraph (d)(4) to 
read as follows:


Sec. 63.152  General reporting and continuous records.

* * * * *
    (b) * * *
    (6) An owner or operator complying with Sec. 63.113(i) shall 
include in the Notification of Compliance Status, or where applicable, 
a supplement to the Notification of Compliance Status, the name and 
location of the transferee, and the identification of the Group 1 
process vent.
* * * * *
    (c) * * *
    (4) * * *
    (iv) For gas streams sent for disposal pursuant to Sec. 63.113(i) 
or for process wastewater streams sent for treatment pursuant to 
Sec. 63.132(g), reports of changes in the identity of the transferee.
* * * * *
    (d) * * *
    (4) If an owner or operator transfers for disposal a gas stream 
that has the characteristics specified in Sec. 63.107(b) through (h) or 
meets the criteria specified in Sec. 63.107(i) to an off-site location 
or an on-site location not owned or operated by the owner or operator 
of the source and the vent stream was not included in the information 
submitted with the Notification of Compliance Status or a previous 
periodic report, the owner or operator shall submit a supplemental 
report. The supplemental report shall be submitted no later than [180 
DAYS AFTER THE DATE OF PUBLICATION OF FINAL RULE IN THE Federal 
Register] or with the next periodic report, whichever is later. The 
report shall provide the information listed in paragraphs (d)(4)(i) 
through (iv) of this section.
    (i) The chemical manufacturing process unit(s) that is the origin 
of all or part of the vent stream that exits the process vent.
    (ii) The type(s) of unit operations (i.e., an air oxidation 
reactor, distillation unit, or reactor) that creates the vent stream 
that exits the process vent.
    (iii) For a Group 2 process vent, the last recovery device, if any.
    (iv) For a Group 1 process vent, the identity of the transferee.
* * * * *
    21. The appendix to subpart G is amended by revising tables 12 and 
20 to read as follows:

Appendix to Subpart G--Tables and Figures

* * * * *

                           Table 12.--Monitoring Requirements for Treatment Processes
----------------------------------------------------------------------------------------------------------------
                                        Parameters to be
          To comply with                   monitored                  Frequency                  Methods
----------------------------------------------------------------------------------------------------------------
1. Required mass removal of Table  Appropriate parameters as  Appropriate frequency as  Appropriate methods as
 8/and or Table 9 compound(s)       specified in Sec.          specified in Sec.         specified in Sec.
 from wastewater treated in a       63.143(c) and approved     63.143 and as approved    63.143 and as approved
 properly operated biological       by permitting authority.   by permitting authority.  by permitting
 treatment unit Sec.  63.138(f)                                                          authority.
 Sec.  63.138(g).
2. Steam stripper................  Steam flow rate..........  Continuously............  Integrating steam flow
                                                                                         monitoring device
                                                                                         equipped with a
                                                                                         continuous recorder.

[[Page 3184]]

 
                                   Wastewater feed mass flow  Continuously............  Liquid flow meter
                                    rate.                                                installed at stripper
                                                                                         influent and equipped
                                                                                         with a continuous
                                                                                         recorder.
                                   Wastewater feed            Continuously............  Liquid temperature
                                    temperature.                                         monitoring device
                                                                                         installed at stripper
                                                                                         influent and equipped
                                                                                         with a continuous
                                                                                         recorder.
3. Alternative monitoring          Other parameters may be
 parameters.                        monitored upon approval
                                    from the Administrator
                                    in accordance with the
                                    requirements specified
                                    in Sec.  63.151(f).
 
*                  *                  *                  *                  *                  *
                                                        *
----------------------------------------------------------------------------------------------------------------


   Table 20.--Wastewater--Periodic Reporting Requirements for Control
                Devices Used To Comply With  63.13-63.139
------------------------------------------------------------------------
        Control device                   Reporting requirements
------------------------------------------------------------------------
Thermal incinerator..........  1. Report all daily average <SUP>a</SUP>
                                temperatures that are outside the range
                                established in the NCS <SUP>b</SUP> or operating
                                permit and all operating days when
                                insufficient monitoring data are
                                collected.<SUP>c</SUP>
Catalytic incinerator........  1. Report all daily average <SUP>a</SUP>
                                temperatures that are outside the range
                                established in the NCS <SUP>b</SUP> or operating
                                permit.
                               2. Report all daily average <SUP>a</SUP> temperature
                                differences across the catalyst bed that
                                are outside the range established in the
                                NCS <SUP>b</SUP> or operating permit.
                               3. Report all operating days when
                                insufficient monitoring data are
                                collected.<SUP>c</SUP>
Boiler or process heater with  1. Report all daily average <SUP>a</SUP> firebox
 a design heat input capacity   temperatures that are outside the range
 less than 44 megawatts and     established in the NCS <SUP>b</SUP> or operating
 vent stream is not mixed       permit and all operating days when
 with the primary fuel.         insufficient monitoring data are
                                collected.<SUP>c</SUP>
Flare........................  1. Report the duration of all periods
                                when all pilot flames are absent.
Condenser....................  1. Report all daily average <SUP>a</SUP> exit
                                temperatures that are outside the range
                                established in the NCS <SUP>b</SUP> or operating
                                permit and all operating days when
                                insufficient monitoring data are
                                collected.<SUP>c</SUP>
Carbon adsorber                1. Report all carbon bed regeneration
 (regenerative).                cycles when the total regeneration
                                stream mass or volumetric flow is
                                outside the range established in the NCS
                                <SUP>b</SUP> or operating permit.
                               2. Report all carbon bed regeneration
                                cycles during which the temperature of
                                the carbon bed after regeneration is
                                outside the range established in the NCS
                                <SUP>b</SUP> or operating permit.
                               3. Report all operating days when
                                insufficient monitoring data are
                                collected.<SUP>c</SUP>
Carbon adsorber (non-          1. Report all operating days when
 regenerative).                 inspections not done according to the
                                schedule developed as specified in table
                                13 of this subpart.
                               2. Report all operating days when carbon
                                has not been replaced at the frequency
                                specified in table 13 of this subpart.
All control devices..........  1. Report the times and durations of all
                                periods when the vent stream is diverted
                                through a bypass line or the monitor is
                                not operating, or
                               2. Report all monthly inspections that
                                show the valves are moved to the
                                diverting position or the seal has been
                                changed.
------------------------------------------------------------------------
<SUP>a</SUP> The daily average is the average of all values recorded during the
  operating day, as specified in Sec.  63.147(d).
<SUP>b</SUP> NCS = Notification of Compliance Status described in Sec.  63.152.
<SUP>c</SUP> The periodic reports shall include the duration of periods when
  monitoring data are not collected for each excursion as defined in
  Sec.  63.152(c)(2)(ii)(A).

* * * * *

Subpart H--National Emission Standards for Organic Hazardous Air 
Pollutants for Equipment Leaks

    22. Section 63.180 is amended by revising paragraph (e) to read as 
follows:


Sec. 63.180  Test methods and procedures.

* * * * *
    (e) When a flare is used to comply with Sec. 63.172(d), the owner 
or operator shall comply with paragraphs (e)(1) through (3) of this 
section. The owner or operator is not required to conduct a performance 
test to determine percent emission reduction or outlet organic HAP or 
TOC concentration.
    (1) Conduct a visible emission test using the techniques specified 
in Sec. 63.11(b)(4).
    (2) Determine the net heating value of the gas being combusted, 
using the techniques specified in Sec. 63.11(b)(6).
    (3) Determine the exit velocity using the techniques specified in 
either Sec. 63.11(b)(7)(i) (and Sec. 63.11(b)(7)(iii), where 
applicable) or Sec. 63.11(b)(8), as appropriate.
* * * * *

Appendix C--[Amended]

    23. Appendix C to part 63 is amended by:
    a. Revising the third paragraph in section I;
    b. Revising the introductory text to section III;
    c. In section III.D.1, revising Eqn App.C-4 and the paragraph 
preceding it;
    d. In section III.D.2, revising Eqn App.C-6 and the paragraph 
preceding it;
    e. Adding section III.E;
    f. Adding references 7 and 8 to the References section;
    g. Revising Figure 1;
    h. Adding Form XIII.

[[Page 3185]]

    The additions and revisions read as follows:

Appendix C to Part 63--Determination of the Fraction Biodegraded 
(F<INF>bio</INF>) in a Biological Treatment Unit

I. Purpose

* * * * *
    Unless otherwise specified, the procedures presented in this 
appendix are designed to be applied to thoroughly mixed treatment 
units. A thoroughly mixed treatment unit is a unit that is designed 
and operated to approach or achieve uniform biomass distribution and 
organic compound concentration throughout the aeration unit by 
quickly dispersing the recycled biomass and the wastewater entering 
the unit. Detailed discussion on how to determine if a biological 
treatment unit is thoroughly mixed can be found in reference 7. 
Systems that are not thoroughly mixed treatment units should be 
subdivided into a series of zones that have uniform characteristics 
within each zone. The number of zones required to characterize a 
biological treatment system will depend on the design and operation 
of the treatment system. Detailed discussion on how to determine the 
number of zones in a biological treatment unit and examples of 
determination of f<INF>bio</INF> can be found in reference 8. Each 
zone should then be modeled as a separate unit. The amount of air 
emissions and biodegradation from the modeling of these separate 
zones can then be added to reflect the entire system.
* * * * *

III. Procedures for Determination of f<INF>bio</INF>

    The first step in the analysis to determine if a biological 
treatment unit may be used without being covered and vented through 
a closed-vent system to an air pollution control device, is to 
determine the compound-specific f<INF>bio</INF>. The following 
procedures may be used to determine f<INF>bio</INF>:
    (1) EPA Test Method 304A or 304B (appendix A, part 63)--Method 
for the Determination of Biodegradation Rates of Organic Compounds,
    (2) Performance data with and without biodegradation,
    (3) Inlet and outlet concentration measurements,
    (4) Batch tests,
    (5) Multiple zone concentration measurements.
    All procedures must be executed so that the resulting 
f<INF>bio</INF> is based on the collection system and waste 
management units being in compliance with the regulation. If the 
collection system and waste management units meet the suppression 
requirements at the time of the test, any of the procedures may be 
chosen. If the collection system and waste management units are not 
in compliance at the time of the performance test, then only Method 
304A, 304B, or the batch test shall be chosen. If Method 304A, 304B, 
or the batch test is used, any anticipated changes to the influent 
of the full-scale biological treatment unit that will occur after 
the facility has enclosed the collection system must be represented 
in the influent feed to the benchtop bioreactor unit, or test unit.
    Select one or more appropriate procedures from the five listed 
above based on the availability of site specific data and the type 
of mixing that occurs in the unit (thoroughly mixed or multiple 
mixing zone). If the facility does not have site-specific data on 
the removal efficiency of its biological treatment unit, then 
Procedure 1 or Procedure 4 may be used. Procedure 1 allows the use 
of a benchtop bioreactor to determine the first-order biodegradation 
rate constant. An owner or operator may elect to assume the first 
order biodegradation rate constant is zero for any regulated 
compound(s) present in the wastewater. Procedure 4 explains two 
types of batch tests which may be used to estimate the first order 
biodegradation rate constant. An owner or operator may elect to 
assume the first order biodegradation rate constant is zero for any 
regulated compound(s) present in the wastewater. Procedure 3 would 
be used if the facility has, or measures to determine, data on the 
inlet and outlet individual organic compound concentration for the 
biological treatment unit. Procedure 3 may only be used on a 
thoroughly mixed treatment unit. Procedure 5 is the concentration 
measurement test that can be used for units with multiple mixing 
zones. Procedure 2 is used if a facility has or obtains performance 
data on a biotreatment unit prior to and after addition of the 
microbial mass. An example where Procedure 2 could be used is an 
activated sludge unit where measurements have been taken on inlet 
and exit concentration of organic compounds in the wastewater prior 
to seeding with the microbial mass and start-up of the unit. The 
flow chart in figure 1 outlines the steps to use for each of the 
procedures.
* * * * *

D. Batch Tests (Procedure 4)

* * * * *
    1. * * *
    Equation App. C-3 can be integrated to obtain the following 
equation:

[GRAPHIC] [TIFF OMITTED] TP20JA00.023

    Where:

A=GK<INF>eq</INF>K<INF>s</INF>+Q<INF>m</INF>VX
B=GK<INF>eq</INF>
S<INF>o</INF>=test compound concentration at t=0
* * * * *
    2. * * *
    Equation App. C-5 can be solved analytically to give:
    [GRAPHIC] [TIFF OMITTED] TP20JA00.024
    
E. Multiple Zone Concentration Measurements (Procedure 5)

    Procedure 5 is the concentration measurement method that can be 
used to determine the f<INF>bio</INF> for units that are not thoroughly 
mixed and thus have multiple zones of mixing. As with the other 
procedures, proper determination of f<INF>bio</INF> must be made on a 
system as it would exist under the rule. For purposes of this 
calculation, the biological unit must be divided \1\ into zones with 
uniform characteristics within each zone. The number of zones that is 
used depends on the complexity of the unit. Reference 8, ``Technical 
Support Document for the Evaluation of Aerobic Biological Treatment 
Units with Multiple Mixing Zones,'' is a source for further information 
concerning how to determine the number of zones that should be used for 
evaluating your unit. The following information on the biological unit 
must be available to use this procedure: basic unit variables such as 
inlet and recycle wastewater flow rates, type of agitation, and 
operating conditions; measured representative organic compound 
concentrations in each zone and the inlet and outlet; and estimated 
mass transfer coefficients for each zone. The estimated mass transfer 
coefficient for each compound in each zone is obtained from Form II 
using the characteristics of each zone. A computer model may be used. 
If the Water7 model

[[Page 3186]]

or the most recent update to this model is used, then use Form II-A to 
calculate KL. The TOXCHEM or BASTE model may also be used to calculate 
KL for the biological treatment unit, with the stipulations listed in 
Procedure 304B. Compound concentration measurements for each zone are 
used in Form XIII to calculate the f<INF>bio</INF>. A copy of Form XIII 
is completed for each of the compounds of concern treated in the 
biological unit.
---------------------------------------------------------------------------

    \1\ This is a mathematical division of the actual unit; not 
addition of physical barriers.
---------------------------------------------------------------------------

* * * * *

References

* * * * *
    7. Technical Support Document for Evaluation of Thoroughly Mixed 
Biological Treatment Units. November 1998.
    8. Technical Support Document for the Evaluation of Aerobic 
Biological Treatment Units with Multiple Mixing Zones.
* * * * *

BILLING CODE 6560-50-U
[GRAPHIC] [TIFF OMITTED] TP20JA00.025


[[Page 3187]]


[GRAPHIC] [TIFF OMITTED] TP20JA00.026


[FR Doc. 1070 Filed 1-19-00; 8:45am]
BILLING CODE 6560-50-C


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