6560-50-P

ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 63

[EPA-HQ-OAR-2012-0360; FRL-9923-26-OAR]

RIN 2060-AR47

National Emission Standards for Hazardous Air Pollutants: OffSite Waste and Recovery Operations

AGENCY: Environmental Protection Agency.

ACTION: Final rule.

SUMMARY: This action finalizes the residual risk and technology 

review (RTR) conducted for the Off-Site Waste and Recovery 

Operations (OSWRO) source category regulated under national 

emission standards for hazardous air pollutants (NESHAP). In 

addition, the Environmental Protection Agency (EPA) is 

finalizing amendments to correct and clarify regulatory 

provisions related to emissions during periods of startup, 

shutdown and malfunction (SSM); add requirements for reporting 

of performance testing through the Electronic Reporting Tool

(ERT); revise the routine maintenance provisions; clarify 

provisions pertaining to open-ended valves and lines (OELs); add 

monitoring requirements for pressure relief devices (PRDs); 

clarify provisions for some performance test methods and 

procedures; and make several minor clarifications and 

corrections. The revisions to the final rule increase the level 
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of emissions control and environmental protection provided by 

the OSWRO NESHAP.

DATES: This final action is effective on [insert date of 

publication in the Federal Register]

ADDRESSES: The EPA has established a docket for this action 

under Docket ID No. EPA–HQ–OAR–2012–0360. All documents in the 

docket are listed on the http://www.regulations.gov Web site.

Although listed in the index, some information is not publicly 

available, e.g., confidential business information (CBI) or 

other information whose disclosure is restricted by statute. 

Certain other material, such as copyrighted material, is not 

placed on the Internet, and will be publicly available only in 

hard copy form. Publicly available docket materials are 

available either electronically through

http://www.regulations.gov, or in hard copy at the EPA Docket 

Center, EPA WJC West Building, Room Number 3334, 1301 

Constitution Ave., NW, Washington, DC. The Public Reading Room 

hours of operation are 8:30 a.m. to 4:30 p.m. Eastern Standard 

Time (EST), Monday through Friday. The telephone number for the 

Public Reading Room is (202) 566–1744, and the telephone number 

for the Air and Radiation Docket and Information Center is (202) 

566–1742.

FOR FURTHER INFORMATION CONTACT: For questions about this final 

action, contact Ms. Paula Hirtz, Sector Policies and Programs 
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Division (E143-01), Office of Air Quality Planning and Standards

(OAQPS), U.S. Environmental Protection Agency, Research Triangle 

Park, North Carolina 27711; telephone number: (919) 541–2618; 

fax number: (919) 541–0246; and email address: 

hirtz.paula@epa.gov. For specific information regarding the risk 

modeling methodology, contact Ms. Darcie Smith, Health and 

Environmental Impacts Division (C504-06), Office of Air Quality 

Planning and Standards, U.S. Environmental Protection Agency, 

Research Triangle Park, North Carolina 27711; telephone number: 

(919) 541–2076; fax number: (919) 541–0840; and email address: 

smith.darcie@epa.gov. For information about the applicability of 

the NESHAP to a particular entity, contact Ms. Marcia Mia, EPA 

Office of Enforcement and Compliance Assurance; U.S. EPA, WJC 

West Building, 1200 Pennsylvania Ave., NW, Washington, DC 20460; 

telephone number: (202) 564-7042; and email address:

mia.marcia@epa.gov.

SUPPLEMENTARY INFORMATION:

Preamble Acronyms and Abbreviations. We use multiple 

acronyms and terms in this preamble. While this list may not be 

exhaustive, to ease the reading of this preamble and for 

reference purposes, the EPA defines the following terms and 

acronyms here:

ADAF age-dependent adjustment factors

BDT best demonstrated technology

CAA Clean Air Act
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CBI confidential business information

CDX Central Data Exchange

CEDRI Compliance and Emissions Data Reporting Interface

CFR Code of Federal Regulations

CRA Congressional Review Act

CWA Clean Water Act

EPA Environmental Protection Agency

EPCRA Emergency Planning and Community Right-To-Know Act 

ERT Electronic Reporting Tool

FR Federal Register

HAP hazardous air pollutants

HON Hazardous Organic NESHAP

HQ hazard quotient

ICR information collection request

IPT integrated project team

kPa kilopascals

LDAR leak detection and repair

MACT maximum achievable control technology

MIR maximum individual risk

MON Miscellaneous Organic NESHAP

NAICS North American Industry Classification System

NATA National Air Toxics Assessment

NEIC National Enforcement Investigations Center

NESHAP National Emissions Standards for Hazardous Air 

Pollutants

NRDC Natural Resources Defense Council

NTTAA National Technology Transfer and Advancement Act

OAQPS Office of Air Quality Planning and Standards

OECA Office of Enforcement and Compliance Assurance

OEL open-ended valve or line

OMB Office of Management and Budget

OSHA Occupational Safety and Health Administration 

OSWRO off-site waste and recovery operations

PB-HAP hazardous air pollutants known to be persistent and 

bio-accumulative in the environment

POM polycyclic organic matter

ppm parts per million

ppmv parts per million by volume

ppmw parts per million by weight
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PRA Paperwork Reduction Act

PRD pressure relief device

psi pounds per square inch

RCRA Resource Conservation and Recovery Act

RFA Regulatory Flexibility Act

RQ reportable quantity

RTR residual risk and technology review

SBA Small Business Administration

SCAQMD South Coast Air Quality Management District

SOCMI synthetic organic chemical manufacturing industry

SSM startup, shutdown and malfunction

TOSHI target organ-specific hazard index

tpy tons per year 

TSDF hazardous waste treatment, storage and disposal 

facilities

TTN Technology Transfer Network

UMRA Unfunded Mandates Reform Act

VCS voluntary consensus standards

VOC volatile organic compound

VOHAP volatile organic hazardous air pollutant

XML extensible markup language

Background Information. On July 2, 2014 (79 FR 37850), the 

EPA proposed revisions to the OSWRO NESHAP based on our RTR, and 

we also proposed to amend provisions related to emissions during 

periods of SSM, to add requirements for electronic reporting of 

performance testing and monitoring requirements for PRDs, to 

revise routine maintenance provisions, to clarify provisions for 

OELs and for some performance test methods and procedures and to 

make several minor clarifications and corrections. In this 

action, we are finalizing decisions and revisions for the rule.

We summarize key comments we timely received regarding the 

proposed rule and provide our responses in this preamble. A 
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summary of the public comments on the proposal not presented in 

the preamble and the EPA’s responses to those comments are 

available in Docket ID No. EPA-HQ-OAR-2012-0360. The background 

information also includes discussion and technical analyses of 

other issues addressed in this final rule. A “track changes” 

version of the regulatory language that incorporates the changes 

in this action is available in the docket.

Organization of this Document. The information in this preamble 

is organized as follows:

I. General Information

A. Does this action apply to me?

B. Where can I get a copy of this document and other 

related information?

C. Judicial Review and Administrative Reconsideration

II. Background

A. What is the statutory authority for this action?

B. What is the OSWRO source category and how does the 

NESHAP promulgated on July 1, 1996, regulate HAP 

emissions from the source category?

C. What changes have been made to the standards since 

promulgation of the NESHAP for the OSWRO source 

category?

D. What changes did we propose for the OSWRO source 

category in our July 2, 2014, proposal?

III. What is included in this final rule?

A. What are the final rule amendments based on the risk 

review for the OSWRO source category?

B. What are the final rule amendments based on the 

technology review for the OSWRO source category?

C. What are the final rule amendments addressing emissions 

during periods of startup, shutdown and malfunction?

D. What other changes have been made to the NESHAP?

E. What are the effective and compliance dates of the 

revisions to the OSWRO NESHAP?

IV. What is the rationale for our final decisions and amendments 

for the OSWRO source category?

A. Residual Risk Review for the OSWRO Source Category

B. Technology Review for the OSWRO Source Category
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C. Startup, Shutdown and Malfunction Provisions for the 

OSWRO Source Category

D. Other Changes Made to the OSWRO NESHAP

V. Summary of Cost, Environmental and Economic Impacts and 

Additional Analyses Conducted

A. What are the affected sources?

B. What are the air quality impacts?

C. What are the cost impacts?

D. What are the economic impacts?

E. What are the benefits?

F. What analysis of environmental justice did we conduct?

G. What analysis of children’s environmental health did we 

conduct?

VI. Statutory and Executive Order Reviews

A. Executive Order 12866: Regulatory Planning and Review 

and Executive Order 13563: Improving Regulation and 

Regulatory Review

B. Paperwork Reduction Act (PRA)

C. Regulatory Flexibility Act (RFA)

D. Unfunded Mandates Reform Act (UMRA)

E. Executive Order 13132: Federalism

F. Executive Order 13175: Consultation and Coordination 

with Indian Tribal Governments

G. Executive Order 13045: Protection of Children from 

Environmental Health Risks and Safety Risks

H. Executive Order 13211: Actions Concerning Regulations 

That Significantly Affect Energy Supply, Distribution or 

Use

I. National Technology Transfer and Advancement Act (NTTAA)

J. Executive Order 12898: Federal Actions to Address 

Environmental Justice in Minority Populations and LowIncome Populations

K. Congressional Review Act (CRA)

I. General Information

A. Does this action apply to me?

Regulated Entities. Categories and entities potentially 

regulated by this action are shown in Table 1 of this preamble.

Table 1. NESHAP and Industrial Source Category Affected By 

This Final Action

NESHAP and 

source 

category

Examples of regulated entities
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Off-Site 

Waste and 

Recovery 

Operations

Businesses or government agencies that operate 

any of the following: Hazardous waste treatment, 

storage and disposal facilities (TSDF); Resource 

Conservation and Recovery Act (RCRA) exempt 

hazardous wastewater treatment facilities; 

nonhazardous wastewater treatment facilities 

other than publicly-owned treatment works; used 

solvent recovery plants; RCRA exempt hazardous 

waste recycling operations; used oil rerefineries

Table 1 of this preamble is not intended to be exhaustive, 

but rather provides a guide for readers regarding entities 

likely to be affected by the final action for the source 

category listed. To determine whether your facility is affected, 

you should examine the applicability criteria in the appropriate 

NESHAP. If you have any questions regarding the applicability of 

any aspect of this NESHAP, please contact the appropriate person 

listed in the preceding FOR FURTHER INFORMATION CONTACT section 

of this preamble.

B. Where can I get a copy of this document and other related 

information?

In addition to being available in the docket, an electronic 

copy of this final action will be available on the Internet

through the Technology Transfer Network (TTN) Web site, a forum 

for information and technology exchange in various areas or air 

pollution control. Following signature by the EPA Administrator, 

the EPA will post a copy of this final action at 

http://www.epa.gov/ttn/atw/offwaste/oswropg.html. Following
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publication in the Federal Register, the EPA will post the 

Federal Register version and key technical documents at this 

same Web site. 

Additional information is available on the RTR Web site at 

http://www.epa.gov/ttn/atw/rrisk/rtrpg.html. This information 

includes an overview of the RTR program, links to project Web

sites for the RTR source categories and detailed emissions and 

other data we used as inputs to the risk assessments.

C. Judicial Review and Administrative Reconsideration

Under Clean Air Act (CAA) section 307(b)(1), judicial 

review of this final action is available only by filing a 

petition for review in the United States Court of Appeals for 

the District of Columbia Circuit by [insert date 60 days after 

date of publication in the Federal Register]. Under CAA section 

307(b)(2), the requirements established by this final rule may 

not be challenged separately in any civil or criminal 

proceedings brought by the EPA to enforce the requirements.

Section 307(d)(7)(B) of the CAA further provides that 

“[o]nly an objection to a rule or procedure which was raised 

with reasonable specificity during the period for public comment 

(including any public hearing) may be raised during judicial 

review.” This section also provides a mechanism for the EPA to 

reconsider the rule, “[i]f the person raising an objection can 

demonstrate to the EPA that it was impracticable to raise such 
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objection within [the period for public comment] or if the 

grounds for such objection arose after the period for public 

comment (but within the time specified for judicial review) and 

if such objection is of central relevance to the outcome of the 

rule.” Any person seeking to make such a demonstration should 

submit a Petition for Reconsideration to the Office of the 

Administrator, U.S. EPA, Room 3000, EPA WJC West Building, 1200 

Pennsylvania Ave., NW, Washington, DC 20460, with a copy to both 

the person(s) listed in the preceding FOR FURTHER INFORMATION 

CONTACT section, and the Associate General Counsel for the Air 

and Radiation Law Office, Office of General Counsel (Mail Code 

2344A), U.S. EPA, 1200 Pennsylvania Ave., NW, Washington, DC 

20460.

II. Background

A. What is the statutory authority for this action? 

Section 112 of the CAA establishes a two-stage regulatory 

process to address emissions of hazardous air pollutants (HAP)

from stationary sources. In the first stage, we must identify 

categories of sources emitting one or more of the HAP listed in 

CAA section 112(b) and then promulgate technology-based NESHAP 

for those sources. “Major sources” are those that emit, or have 

the potential to emit, any single HAP at a rate of 10 tons per 

year (tpy) or more, or any combination of HAP at a rate of 25 

tpy or more. For major sources, these standards are commonly 
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referred to as maximum achievable control technology (MACT) 

standards and must reflect the maximum degree of emission 

reductions of HAP achievable (after considering cost, energy 

requirements and non-air quality health and environmental 

impacts). In developing MACT standards, CAA section 112(d)(2) 

directs the EPA to consider the application of measures, 

processes, methods, systems or techniques, including but not 

limited to those that reduce the volume of or eliminate HAP 

emissions through process changes, substitution of materials or

other modifications; enclose systems or processes to eliminate 

emissions; collect, capture or treat HAP when released from a 

process, stack, storage or fugitive emissions point; are design, 

equipment, work practice or operational standards; or any 

combination of the above.

For these MACT standards, the statute specifies certain 

minimum stringency requirements, which are referred to as MACT 

floor requirements and may not be based on cost considerations. 

See CAA section 112(d)(3). For new sources, the MACT floor 

cannot be less stringent than the emission control achieved in 

practice by the best-controlled similar source. The MACT 

standards for existing sources can be less stringent than floors 

for new sources, but they cannot be less stringent than the 

average emission limitation achieved by the best-performing 12 

percent of existing sources in the category or subcategory (or 
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the best-performing five sources for categories or subcategories 

with fewer than 30 sources). In developing MACT standards, we 

must also consider control options that are more stringent than 

the floor, under CAA section 112(d)(2). We may establish 

standards more stringent than the floor, based on the 

consideration of the cost of achieving the emissions reductions, 

any non-air quality health and environmental impacts and energy 

requirements.

In the second stage of the regulatory process, the CAA 

requires the EPA to undertake two different analyses, which we 

refer to as the technology review and the residual risk review. 

Under the technology review, we must review the technology-based 

standards and revise them “as necessary (taking into account 

developments in practices, processes, and control technologies)” 

no less frequently than every 8 years, pursuant to CAA section 

112(d)(6). Under the residual risk review, we must evaluate the 

risk to public health remaining after application of the 

technology-based standards and revise the standards, if 

necessary, to provide an ample margin of safety to protect 

public health or to prevent, taking into consideration costs, 

energy, safety and other relevant factors, an adverse 

environmental effect. The residual risk review is required 

within 8 years after promulgation of the technology-based 

standards, pursuant to CAA section 112(f). In conducting the 
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residual risk review, if the EPA determines that the current 

standards provide an ample margin of safety to protect public 

health, it is not necessary to revise the MACT standards 

pursuant to CAA section 112(f).1 For more information on the 

statutory authority for this rule, see 79 FR 37850.

B. What is the OSWRO source category and how does the NESHAP 

promulgated on July 1, 1996, regulate HAP emissions from the 

source category?

The EPA promulgated the OSWRO NESHAP on July 1, 1996 (61 FR 

34139). The standards are codified at 40 CFR part 63, subpart 

DD. The OSWRO industry consists of facilities that conduct 

operations to manage, convey or handle wastes or recoverable 

materials that are received from other facilities. The source 

category covered by the OSWRO NESHAP currently includes 

approximately 56 facilities. However, based on available permit 

information, seven facilities are known to be exempt from most 

of the rule requirements due to the low HAP content of the offsite waste they receive or because they comply instead with 40 

CFR part 61, subpart FF, as allowed by the OSWRO NESHAP, and 

 

1 The U.S. Court of Appeals for the District of Columbia Circuit has affirmed this 

approach of implementing CAA section 112(f)(2)(A): NRDC v. EPA, 529 F.3d 1077, 1083 

(D.C. Cir. 2008) (“If EPA determines that the existing technology-based standards 

provide an ’ample margin of safety,’ then the Agency is free to readopt those 

standards during the residual risk rulemaking.”).
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they are not expected to be affected by the final rule 

amendments.

In general, the rule applies to waste management units and 

recovery operations that are located at major sources of HAP 

emissions, are used to manage, convey or handle used oil, used 

solvent or waste received from other facilities, and contain at 

least one of 97 organic HAP specified in the rule.2 The HAP 

emission sources at facilities subject to the OSWRO NESHAP are 

tanks, containers, surface impoundments, oil-water separators, 

organic-water separators, process vents and transfer systems 

used to manage offsite material and equipment leaks. The MACT 

standards regulate these emissions sources through emission 

limits, equipment standards and work practices.

C. What changes have been made to the standards since 

promulgation of the NESHAP for the OSWRO source category?

Rule changes have been made to the OSWRO NESHAP since the 

promulgation of the NESHAP on July 1, 1996, in several separate 

actions. On July 20, 1999 (64 FR 38950), the EPA issued a direct 

final rule that amended specific provisions in the rule to 

resolve issues and questions raised after promulgation of the 

final rule. In this action, the EPA also amended other rule 

 

2 The OSWRO MACT rule defines “waste,” “used oil” and “used solvent” in 40 CFR 

63.681 Definitions.
Page 15 of 180

language to correct technical omissions, to make requirements 

consistent with other related air rules, and to correct 

typographical, printing and grammatical errors. On January 8, 

2001 (66 FR 1263), the EPA published technical corrections and 

minor technical amendments for the OSWRO NESHAP. In addition, 

the EPA published proposed and final rules on January 16, 2002 

(67 FR 2286), and June 23, 2003 (68 FR 37334), respectively, to 

clarify which parts of several existing NESHAP, including the 

OSWRO NESHAP, can be delegated to state, local and tribal 

agencies. The EPA also published proposed and final rules on 

July 29, 2005 (70 FR 43992), and April 20, 2006 (71 FR 20446),

respectively, to revise certain aspects of SSM requirements in 

several existing NESHAP, including the OSWRO NESHAP. 

D. What changes did we propose for the OSWRO source category in 

our July 2, 2014, proposal?

On July 2, 2014 (79 FR 37850), the EPA published proposed 

amendments to the OSWRO NESHAP based on the RTR analyses and 

also proposed other revisions. The proposed revisions include 

the following:

 Revisions to the tank requirements to require increased 

control of emissions for tanks in a specific size range that 

also contain material above a specified vapor pressure; 

 Revisions to the equipment leak requirements to remove the 

option to comply with either 40 CFR part 63, subpart H or 40 
Page 16 of 180

CFR part 61, subpart V, and require compliance with only 40 

CFR part 63, subpart H;

 Revisions to requirements related to emissions during periods 

of SSM;

 The addition of requirements for reporting of performance 

testing through the ERT;

 Revisions to the routine maintenance provisions to limit the 

applicability of the provisions to tanks;

 Clarifications to the “sealed” requirement of the provisions 

for OELs; 

 Addition of monitoring requirements for PRDs; 

 Clarification of provisions for some performance test methods 

and procedures; and 

 Several minor clarifications and corrections.

III. What is included in this final rule?

Today’s action finalizes the EPA’s determinations pursuant 

to the RTR provisions of CAA section 112 for the OSWRO source 

category, and amends the OSWRO NESHAP, as proposed, based on 

those determinations. Today’s action also finalizes the proposed 

changes to the NESHAP described in section II.D. of this

preamble. We are also finalizing minor changes to the NESHAP in 

consideration of comments received during the public comment 

period for the proposed rulemaking, as described in section IV. 
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D.2 of this preamble. In the following subsections, we introduce 

and summarize the final amendments to the OSWRO NESHAP.

A. What are the final rule amendments based on the risk review 

for the OSWRO source category?

Pursuant to CAA section 112(f), we are revising the tank 

and equipment leak requirements of the OSWRO NESHAP. 

Specifically, as we proposed, we are finalizing our 

determination that risks from the OSWRO source category are 

acceptable, considering all of the health information and 

factors evaluated and also considering risk estimation 

uncertainty; we are finalizing revisions to the tank 

requirements to require increased control of emissions for tanks 

in a specific size range that also contain material above a

specified vapor pressure; and we are finalizing revisions to the 

equipment leak requirements to remove the option to comply with 

either 40 CFR part 63, subpart H or 40 CFR part 61, subpart V, 

and require compliance with only 40 CFR part 63, subpart H. We 

evaluated the costs, emissions reductions, energy implications 

and cost effectiveness of these revised standards and determined 

that these measures are cost effective and technically feasible 

and will provide an ample margin of safety to protect public 

health and prevent adverse environmental effects from exposure 

to emissions from the OSWRO source category.
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B. What are the final rule amendments based on the technology 

review for the OSWRO source category?

We determined that there are developments in practices, 

processes and control technologies that warrant revisions to the 

NESHAP for this source category. Therefore, to satisfy the 

requirements of CAA section 112(d)(6), we are revising the MACT 

standards to include those developments. Specifically, as we 

proposed, we are finalizing revisions to the tank requirements 

to require increased control of emissions for tanks in a 

specific size range that also contain material above a specified 

vapor pressure, and we are finalizing revisions, as proposed, to 

the equipment leak requirements to remove the option to comply 

with either 40 CFR part 63, subpart H or 40 CFR part 61, subpart 

V, and require compliance with only 40 CFR part 63, subpart H.

As noted in section III.A of the preamble, we are concurrently 

promulgating these tank and equipment leak revisions under 

section 112(f)(2) of the CAA to provide an ample margin of 

safety to protect public health.

C. What are the final rule amendments addressing emissions 

during periods of startup, shutdown and malfunction?

We are finalizing, as proposed, changes to the OSWRO NESHAP 

to eliminate the SSM exemption. Consistent with Sierra Club v. 

EPA 551 F. 3d 1019 (D.C. Cir. 2008), the EPA has established 

standards in this rule that apply at all times. Table 2 to 
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Subpart DD of Part 63 (General Provisions applicability table)

is being revised to change several references related to 

requirements that apply during periods of SSM. We also 

eliminated or revised certain recordkeeping and reporting 

requirements related to the eliminated SSM exemption. The EPA 

also made changes to the rule to remove or modify inappropriate,

unnecessary or redundant language in the absence of the SSM 

exemption. We determined that facilities in this source category 

can meet the applicable emission standards in the OSWRO NESHAP 

at all times, including periods of startup and shutdown; 

therefore, the EPA determined that no additional standards are 

needed to address emissions during these periods.

D. What other changes have been made to the NESHAP?

Today’s rule also finalizes, as proposed, revisions to 

several other OSWRO NESHAP requirements. We describe the 

revisions in the following paragraphs. 

To increase the ease and efficiency of data submittal and 

data accessibility, we are finalizing, as proposed, a 

requirement that owners and operators of OSWRO facilities submit 

electronic copies of certain required performance test reports

through an electronic performance test report tool called the 

ERT. This requirement to submit performance test data 

electronically to the EPA does not require any additional 
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performance testing and applies only to those performance tests 

conducted using test methods that are supported by the ERT. 

We are finalizing the proposed revisions to the routine 

maintenance provisions to limit their applicability to tanks

routing emissions to a control device rather than any equipment 

or process routing emissions to a control device. This revision 

restores the OSWRO NESHAP provisions to the original intent for 

them to be consistent with the routine maintenance provisions of 

the Hazardous Organic NESHAP (HON).

To reduce compliance uncertainty associated with “sealed” 

OELs, we are finalizing the proposed revisions to clarify that 

OELs are “sealed” by a cap, blind flange, plug or second valve 

when instrument monitoring of the OEL conducted according to 

Method 21 of 40 CFR part 60, appendix A indicates no readings of 

500 parts per million (ppm) or greater. For OELs that are exempt 

from the requirements to be equipped with a cap, blind flange, 

plug or second valve, we are requiring them to be equipped with 

a flow indicator, seal or locking device. 

To conform with the reasoning of the Court’s ruling in 

Sierra Club v. EPA, we are finalizing the proposed requirements 

regarding releases directly to the atmosphere from safety 

devices, pressure tanks, bypasses and PRDs. These requirements 

prohibit bypasses of control devices and prohibit emissions 

released directly to the atmosphere from PRDs and closure 
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devices on pressure tanks. In addition, we are finalizing the 

proposed recordkeeping and reporting requirements associated 

with releases to the atmosphere from bypasses and PRDs. We are 

also finalizing the proposed requirements that PRDs be monitored 

with a device or monitoring system that is capable of: (1) 

Identifying the pressure release; (2) recording the time and 

duration of each pressure release; and (3) notifying operators

immediately that a pressure release is occurring. 

We are finalizing, as proposed, several minor changes to 

the test methods and procedures required by the NESHAP to 

correct errors and to provide consistency, clarification and 

flexibility. 

In addition, we are finalizing, as proposed, several 

miscellaneous minor changes to improve the clarity of the rule 

requirements.

We are also finalizing minor changes to the NESHAP in 

consideration of comments received during the public comment 

period for the proposed rulemaking, as described in section IV. 

D.2 of this preamble.

E. What are the effective and compliance dates of the revisions 

to the OSWRO NESHAP?

The effective date and compliance dates for the revisions 

to the OSWRO NESHAP being promulgated in this action have not 

changed since proposal. 
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The revisions to the OSWRO NESHAP being promulgated in this 

action are effective on [insert date of publication in the 

Federal Register].

The compliance date for the revised SSM requirements,

electronic reporting requirements, the revised routine 

maintenance provisions, the operating and pressure release 

management requirements for PRDs, and the revised requirements 

regarding bypasses and closure devices on pressure tanks for 

existing OSWRO facilities is the effective date of the standards

[insert date of publication in the Federal Register]. The 

compliance date for existing OSWRO facilities to comply with the 

PRD monitoring requirements is 3 years from the effective date 

of the standards, [insert date 3 years after date of publication 

in the Federal Register]. The compliance date for existing OSWRO 

facilities to comply with the revised tank requirements is 2 

years from the effective date of the standards, [insert date 2 

years after date of publication in the Federal Register]. For 

equipment leaks, the compliance date for existing sources is 1 

year from the effective date of the standards, [insert date 1 

year after date of publication in the Federal Register].

New sources must comply with all of the standards 

immediately upon the effective date of the standard, [insert 

date of publication in the Federal Register], or upon startup, 

whichever is later.
Page 23 of 180

IV. What is the rationale for our final decisions and amendments 

for the OSWRO source category?

For each issue, this section provides a description of what 

we proposed and what we are finalizing for the issue, the EPA’s 

rationale for the final decisions and amendments and a summary 

of key comments and responses. For all comments not discussed in 

this preamble, comment summaries and the EPA’s responses can be 

found in the comment summary and response document available in 

the docket.

A. Residual Risk Review for the OSWRO Source Category

1. What did we propose pursuant to CAA section 112(f) for the 

OSWRO source category?

Pursuant to CAA section 112(f), we conducted a residual 

risk review and presented the results of this review, along with 

our proposed decisions regarding risk acceptability and ample 

margin of safety, in the July 2, 2014, proposed rule for the 

OSWRO NESHAP (79 FR 37850). The results of the risk assessment 

are presented briefly below in Table 2, and in more detail in 

the residual risk document, Residual Risk Assessment for the 

Off-Site Waste and Recovery Operations Source Category in 

Support of the February 2015 Risk and Technology Review Final 

Rule, which is available in the docket for this rulemaking.

Based on actual emissions for the OSWRO source category, the 

maximum individual risk (MIR) was estimated to be up to 9-in-1 
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million, the maximum chronic non-cancer target organ-specific 

hazard index (TOSHI) value was estimated to be up to 0.6, and 

the maximum off-site acute hazard quotient (HQ) value was 

estimated to be up to 1. The total estimated national cancer 

incidence from this source category, based on actual emission 

levels, was 0.02 excess cancer cases per year, or one case in 

every 50 years. Based on MACT-allowable emissions for the OSWRO

source category, the MIR was estimated to be up to 20-in-1 

million, and the maximum chronic non-cancer TOSHI value was 

estimated to be up to 1. We also found there were emissions of 

one persistent and bio-accumulative HAP (PB-HAP) with an 

available RTR multipathway screening value, and the reported 

emissions of this HAP, 2-acetylaminofluorene (which is a 

polycyclic organic matter (POM) compound), were below the 

multipathway screening value for this compound. Emissions of 

three environmental HAP, POM, hydrogen chloride and hydrogen 

fluoride, were reported by OSWRO facilities. For each of these 

three HAP, the modeled concentrations were below the respective 

ecological benchmark values. The maximum facility-wide MIR was 

200-in-1 million and the maximum facility-wide TOSHI was 4. 

These risks were found to be due to emissions from non-OSWRO 

processes at the facility site and were based on actual 

emissions. We weighed all health risk factors in our risk 
Page 25 of 180

acceptability determination, and we proposed that the residual 

risks from the OSWRO source category are acceptable.

Table 2. Off-Site Waste and Recovery Operations Inhalation Risk 

Assessment Results

Maximum

individual

cancer risk

(in 1 million)a

Estimated 

population

at 

increased 

risk 

levels of 

cancer

Estimated 

annual

cancer

incidence 

(cases 

per year)

Maximum

chronic non-cancer

TOSHIb Maximum 

screening 

acute 

noncancer HQd

Actual 

emissions 

level

MACTallowable 

emissions 

levelc

Actual 

emissions 

level

MACTallowable 

emissions 

level

9 20

≥ 1-in-1 

million: 

210,000

≥ 10-in-1 

million: 0

0.02 0.6 1

HQREL = 1 

(glycol 

ethers) 

a Estimated maximum individual excess lifetime cancer risk due to HAP 

emissions from the source category.

b Maximum TOSHI. The target organ with the highest TOSHI for the OSWRO source 

category for both actual and MACT-allowable emissions is the respiratory 

system. 

c The development of allowable emission estimates can be found in the memo 

MACT-Allowable Emissions for the Off-Site Waste and Recovery Operations 

Source Category, which is available in the docket for this action.

d The maximum off-site acute value of 1 for actual emissions is driven by 

emissions of glycol ethers. Acute assessments are not performed with MACTallowable emissions.

We then considered whether the OSWRO NESHAP provides an 

ample margin of safety to protect public health and whether more 

stringent standards are necessary to prevent, taking into 

consideration costs, energy, safety and other relevant factors, 

an adverse environmental effect. In considering whether the 

standards should be tightened to provide an ample margin of 

safety to protect public health, we considered the same risk 

factors that we considered for our acceptability determination 

and also considered the costs, technological feasibility and 

other relevant factors related to emissions control options that 
Page 26 of 180

might reduce risk associated with emissions from the source 

category. The control options identified to reduce risk were the 

same as those identified under the technology review for the 

OSWRO source category. Based on that analysis, we proposed to 

require more stringent controls for tanks of certain sizes and 

containing materials above a certain vapor pressure. We also 

proposed to require facilities to comply with the more stringent 

leak detection and repair (LDAR) program of 40 CFR part 63, 

subpart H rather than to allow facilities to comply with either 

40 CFR part 63, subpart H or 40 CFR part 61, subpart V. 

Furthermore, we proposed that additional HAP emissions controls 

for OSWRO process vents are not necessary to provide an ample 

margin of safety. Based on the results of our screening analysis 

for risks to the environment, we also proposed that more 

stringent standards are not necessary to prevent an adverse 

environmental effect.

2. How did the risk review change for the OSWRO source category

since the proposed rule?

Information received by the EPA during the proposal comment 

period indicates that four additional facilities, not included 

in the risk review for the OSWRO source category, are subject to 

the OSWRO NESHAP. These facilities include Eastman Chemical 

Company in Kingsport, Tennessee; Eastman Chemical Company in 
Page 27 of 180

Longview, Texas; E. I. DuPont de Nemours and Company in Orange, 

Texas; and E. I. DuPont de Nemours and Company in Axis, Alabama.

To determine whether to conduct additional risk modeling 

for these facilities, we reviewed the title V permits and the 

results of previously performed risk modeling for these 

facilities. The review of the facility title V permits, as well 

as conversations with facility representatives, indicated that 

these facilities are primarily chemical manufacturing plants

with processes subject to other NESHAPs that also process some 

amount of waste received from other facilities within their

companies. A review of previously modeled facility-wide risks 

for these four facilities as part of the risk reviews for the 

other NESHAP indicate that the maximum facility-wide cancer 

risks due to emissions of HAP range from 6-in-1 million to 40-

in-1 million. These risks are relatively low when compared to 

the upper end of the range of acceptability of 100-in-1 million. 

The maximum facility-wide non-cancer risks due to HAP emissions 

range from 0.08 to 1. In addition, the results show that the 

facility-wide cancer and non-cancer risks are attributed to HAP 

emissions from non-OSWRO processes. As the OSWRO processes are 

minor operations at these facilities, the risk due to OSWRO 

operations is expected to be a small fraction of the facilitywide risk. 
Page 28 of 180

Adding these facilities to the dataset and performing 

additional modeling would not be expected to result in increased 

maximum risks from the source category, for the reasons 

discussed above. Thus, we determined that additional modeling to 

include these facilities is not necessary, and, based on 

available information, the risks from these four facilities do 

not change our decisions regarding risk acceptability or ample 

margin of safety for the OSWRO source category. We have not 

otherwise changed any aspects of our risk review since the 

proposal.

3. What key comments did we receive on the risk review, and what 

are our responses?

The comments received on the proposed risk review were 

generally supportive of our determination of risk acceptability 

and ample margin of safety analysis and requirement for 

additional control. A summary of these comments and our 

responses can be found in the comment summary and response 

document available in the docket for this action (EPA-HQ-OAR2012-0360).

4. What is the rationale for our final decisions for the risk 

review?

For the reasons explained in the proposed rule, we 

determined that the risks from the OSWRO source category are 

acceptable, and the revised requirements for tanks and equipment 
Page 29 of 180

leaks described above will provide an ample margin of safety to 

protect public. In addition, for the reasons explained in the 

proposal, we determined that more stringent standards are not 

necessary to prevent an adverse environmental effect. Since 

proposal, neither the risk assessment nor our determinations 

regarding risk acceptability, ample margin of safety or adverse 

environmental effects have changed. Therefore, pursuant to CAA 

section 112(f)(2), we are revising the OSWRO NESHAP to require 

the 40 CFR part 63, subpart H LDAR program and more stringent 

emissions controls for certain tanks to provide an ample margin 

of safety to protect public.

B. Technology Review for the OSWRO Source Category

1. What did we propose pursuant to CAA section 112(d)(6) for the 

OSWRO source category?

Pursuant to CAA section 112(d)(6), we conducted a 

technology review, which focused on identifying and evaluating 

developments in practices, processes and control technologies 

for the emission sources in the OSWRO source category. At 

proposal, we identified developments in practices, processes or 

control technologies for process vents, tanks and equipment 

leaks.

For process vents, one potential control technology was

identified at proposal, use of a regenerative thermal oxidizer, 

which could increase the emissions capture and control 
Page 30 of 180

efficiency from 95 percent to 98 percent for those process vents

that are currently controlled with a carbon adsorption system or 

other device achieving 95-percent control. We estimated an 

additional emission reduction of 10 tpy of HAP would be 

associated with this increase in emissions control efficiency, 

and the estimated costs would be $350,000 per ton of HAP 

emission reduction.

For tanks, we identified two potential developments in 

practices and control techniques at proposal. Option 1 would 

lower the vapor pressure threshold above which “Level 2” control 

would be required for some tanks. “Level 2” control essentially 

requires one of five options: (1) A fixed roof tank equipped 

with an internal floating roof; (2) a fixed roof tank equipped 

with an external floating roof; (3) a tank with a vapor-tight 

cover and vented through a closed-vent system to a control 

device that has an efficiency of 95 percent or more; (4) a

pressure tank; or (5) a tank inside a permanent total enclosure 

that is vented through a closed-vent system to an enclosed 

combustion control device. Option 1 would require Level 2 

emissions control for tanks with capacities greater than or

equal to 75 cubic meters (m

3), but less than 151 m3, if the vapor 

pressure of the stored material is 13 kilopascals (kPa) or 

greater, instead of 27.6 kPa or greater as required by the 

current MACT standard. Option 2 would revise the vapor pressure 
Page 31 of 180

threshold as in Option 1 and increase the required control

efficiency from the current 95-percent to a 98-percent emissions 

reduction for all tanks required to use Level 2 controls. For 

tank Option 1, we estimated an additional emission reduction of 

up to 73 tpy and estimated the costs would be $300 per ton of 

HAP emission reduction. For tank Option 2, we estimated the HAP 

emissions reduction incremental to Option 1 would be

approximately 22 tpy and the incremental cost effectiveness 

between Option 1 and Option 2 would be $56,000 per ton of HAP 

emission reduction.

For equipment leaks, we identified the more stringent leak 

definitions of 40 CFR part 63, subpart H over those of 40 CFR 

part 61, subpart V as a development in practices, processes or 

control technologies at proposal. To implement the subpart H 

LDAR program, two options were identified: Option 1 - switching 

from the subpart V LDAR program to the subpart H LDAR program, 

without the connector monitoring requirements; Option 2 -

switching from the subpart V LDAR program to the subpart H LDAR 

program, with the connector monitoring requirements. For Option 

1, we estimated an additional emission reduction of up to 69 tpy

and estimated the costs would be $1,000 per ton of HAP emission 

reduction. For Option 2, we estimated the HAP emissions 

reduction incremental to Option 1 would be approximately 70 tpy 
Page 32 of 180

and the incremental cost effectiveness between Option 1 and 

Option 2 would be $7,000 per ton of HAP emission reduction.

Based on the costs and the emission reductions that would 

be achieved with the identified developments, we proposed to 

revise the MACT standard pursuant to CAA section 112(d)(6) to 

require Level 2 controls for tanks with capacities greater than 

or equal to 75 m3, but less than 151 m3, if the vapor pressure of 

the stored material is 13 kPa or greater and to require 

facilities to comply with the subpart H LDAR program, including 

the subpart H requirements for connectors in gas/vapor service 

and in light liquid service. We proposed that it was not 

necessary to revise the MACT standards pursuant to CAA section 

112(d)(6) to require 98-percent control, based on the use of a 

regenerative thermal oxidizer, for process vents. More 

information concerning our technology review can be found in the 

memorandum titled, Technology Review and Cost Impacts for the 

Proposed Amendments to the Off-Site Waste and Recovery 

Operations Source Category, which is available in the docket,

and in the preamble to the proposed rule, 79 FR at 37870 to 

37873.

2. How did the technology review change for the OSWRO source 

category?

a. Tanks
Page 33 of 180

The analysis of the proposed control requirements for tanks 

at existing OSWRO facilities has been revised to reflect new 

data submitted by industry during the comment period. As part of 

its comments, the Cement Kiln Recycling Coalition provided 

information to demonstrate that alternative values or 

assumptions should be used in the analysis of tank emission 

reductions and costs of control. These comments were associated 

with the proposed requirement that Level 2 controls be used for 

tanks with capacities greater than or equal to 75 m3, but less 

than 151 m3, if the vapor pressure of the stored material is 13 

kPa or greater (i.e., Option 1). We reviewed this information, 

determined that several suggested changes were appropriate 

because they more accurately reflect the conditions of tanks in 

the OSWRO source category, and revised our analysis of tank 

emissions reductions and control costs to incorporate the data 

submitted by the commenter, where such incorporation was deemed 

appropriate. The major revisions to the analysis included the 

use of different parameters in estimating HAP emissions per tank 

and the inclusion of additional emissions control equipment and 

ancillary equipment. In addition, through further review of our 

previous analysis, we determined that the number of tanks 

nationwide that would require control under Option 1 was 

overestimated, and we revised the estimated number of tanks that 

would be affected by Option 1 in this analysis.
Page 34 of 180

As shown in Table 3, our revised estimate of the capital 

costs for the tanks Option 1 requirement is approximately

$139,000, and the total annualized costs are estimated to be 

approximately $192,000. The estimated HAP emissions reduction is 

approximately 26 tpy, and the cost effectiveness is 

approximately $7,000/ton. 

Table 3. Revised Estimated Nationwide Emissions Reduction and 

Costs of Control Option 1 for Tanks at OSWRO Facilities

Regulatory 

alternative

HAP 

emissions

reduction 

(tpy)

Capital 

cost ($)

Annual 

costs 

($/yr)

Cost 

effectiveness 

($/ton HAP)

Option 1 26.4 139,000 192,000 7,000

At proposal, we also evaluated the impacts of requiring an 

increased HAP emissions control efficiency of 98 percent based 

on the use of a regenerative thermal oxidizer (i.e., Option 2) 

and found that the costs of Option 2 were not reasonable given 

the level of HAP emissions reductions that it would achieve. No 

comments were received regarding Option 2, and we have not 

revised the analysis for Option 2. 

For further details on the revised tanks analysis, see the 

technical memorandum titled, Revised Technology Review for the 

Off-Site Waste and Recovery Operations Tanks, available in the 

docket for this action.
Page 35 of 180

b. Equipment Leaks

As part of its comments on the proposed rule, one commenter

noted that the EPA did not account for monitoring of agitator 

seals on tanks in its analysis of the costs of implementing the 

more stringent leak definitions for equipment in 40 CFR part 63 

subpart H. We have revised our analysis of the costs and 

emissions reductions associated with switching from the 40 CFR 

part 61, subpart V LDAR program to the 40 CFR part 63, subpart H 

LDAR program to include the expected emissions reductions and 

costs associated with monitoring agitator seals for leaks. Also, 

based on information received after proposal that there are four 

additional facilities in the source category that would be 

subject to the LDAR requirements of the rule, we have revised 

the analysis to include those facilities. We included this 

information in the evaluation of both regulatory options: Option 

1 – switching from a subpart V LDAR program to a subpart H LDAR 

program, without the subpart H connector monitoring requirements 

and Option 2 – switching from a subpart V LDAR program, with the 

subpart H connector monitoring requirements.

The revised estimated costs and emissions reductions 

associated with these two options are shown in Table 4. For 

Option 1 (subpart H without connector monitoring), we estimate 

the capital costs to be approximately $414,000, and the total 

annualized costs are estimated to be approximately $155,000. The 
Page 36 of 180

estimated HAP emissions reduction is approximately 109 tpy, and 

the cost effectiveness is approximately $1,000/ton. For Option 2 

(subpart H with connector monitoring), we estimate the capital 

costs to be approximately $2,089,000, and the total annualized 

costs are estimated to be approximately $664,000. The estimated 

HAP emissions reduction is approximately 185 tpy, and the cost 

effectiveness is approximately $4,000/ton. The incremental cost

effectiveness between Option 1 and Option 2 is approximately 

$7,000.

Table 4. Revised Estimated Nationwide Emissions Reduction and 

Costs of Equipment Leak Control Options at OSWRO Facilities

Regulatory 

alternative

HAP 

emissions 

reduction 

(tpy)

Capital 

cost ($)

Annual 

costs 

($/yr)

Cost 

effectiveness 

($/ton HAP)

Incremental 

cost 

effectiveness 

($/ton HAP 

removed)

Option 1: 

Subpart H, 

no connector 

monitoring

108.7 414,000 155,000 1,000 -----

Option 2: 

Subpart H 

with

connector 

monitoring

184.5 2,089,000 664,000 4,000 7,000

In addition to these revisions to the equipment leak 

analysis, we also considered comments regarding the costs of 

connector monitoring. In its comments on the proposed rule, one 

commenter claimed that the costs the EPA included in its 

analysis for ongoing connector monitoring and administrative 
Page 37 of 180

activities were too low. Although we do not agree with the 

commenter and we continue to believe the costs we used in the 

analysis for these activities are reasonable, we conducted an 

additional analysis to assess the potential effect of using the

values provided by the commenter on the cost effectiveness of 

Option 2. This additional analysis showed there would be a

slight increase in the Option 2 total annualized cost to 

$672,000. The cost effectiveness would remain approximately

$4,000, and the incremental cost effectiveness between Option 1 

and Option 2 would still be approximately $7,000.

For further details on the revised equipment leaks

analysis, see the technical memorandum titled, Revised 

Technology Review for the Off-Site Waste and Recovery Operations 

Equipment Leaks, available in the docket for this action.

c. Process Vents and Other OSWRO Equipment and Processes

For process vents and other equipment and processes at 

OSWRO facilities, the technology review has not changed since 

proposal.

3. What key comments did we receive on the technology review, 

and what are our responses?

The following is a summary of the key comments received 

regarding the OSWRO source category technology review and our 

responses to these comments. Additional comments on the 

technology review and our responses can be found in the comment 
Page 38 of 180

summary and response document available in the docket for this 

action (EPA-HQ-OAR-2012-0360).

Comment: One commenter states that the EPA did not account 

for monitoring of agitator seals on tanks in its analysis of the 

costs of implementing the more stringent leak definitions for 

equipment in 40 CFR part 63, subpart H, and asserts that many 

tanks at OSWRO facilities are equipped with agitators. 

Response: We acknowledge that we did not, prior to 

proposal, analyze the impacts of including monthly monitoring of 

agitators with Method 21 for the proposed rule. We performed 

this analysis in response to comments and have determined that 

the capital costs per facility for agitator monitoring are

approximately $1,000, and the total annualized costs are 

estimated to be approximately $2,000. The estimated HAP 

emissions reduction is approximately 0.7 tpy, and the cost 

effectiveness is approximately $2,000/ton. Agitator monitoring 

would be included in both LDAR Options 1 and 2. To determine the 

effect of including agitator monitoring in the LDAR program

options, we compared the costs and emissions reductions on a per

facility basis rather than for the whole source category to 

avoid issues with differences in the number of facilities 

included in the source category. The effect of including 

agitator monitoring in Option 1 is an increase in the per 

facility capital costs from approximately $7,000 to 
Page 39 of 180

approximately $8,000, an increase in the total annualized costs 

from approximately $1,500 to approximately $3,000, an increase 

in the estimated HAP emissions reduction from approximately 1.5 

to approximately 2.2 tpy, and the cost effectiveness value 

remaining at approximately $1,000/ton. The effect of including 

agitator monitoring in Option 2 is an increase in the per 

facility capital costs from approximately $41,000 to 

approximately $43,000, an increase in the total annualized costs 

from approximately $12,000 to approximately $14,000, and an 

increase in the estimated HAP emissions reduction from 

approximately 3.1 to approximately 3.8 tpy. The cost 

effectiveness remains at approximately $4,000/ton, and the 

incremental cost effectiveness compared with Option 1 remains 

the same at $7,000/ton. Further details on the revised equipment 

leaks analysis are documented in the technical memorandum 

titled, Revised Technology Review for the Off-Site Waste and 

Recovery Operations Equipment Leaks, available in the docket for 

this action.

Based on our analysis of the costs of a 40 CFR part 63, 

subpart H LDAR program with monthly agitator monitoring using 

Method 21, we are finalizing, as proposed, the requirement that 

OSWRO facilities comply with subpart H, including the subpart H 

requirements for connectors in gas/vapor service and in light 

liquid service.
Page 40 of 180

Comment: Several commenters dispute the EPA’s emission 

reduction estimates related to connector monitoring. One of 

these commenters notes that the EPA based its cost-effectiveness 

calculations on the approach from the December 21, 2011,

memorandum, Analysis of Emissions Reduction Techniques for 

Equipment Leaks, developed for the Uniform Standards, and 

provides comments on the approach used in this memorandum. This

commenter and another commenter state that the leak rate factor 

of 1.7 for connectors was determined for the refining industry, 

and the EPA provides no basis that it applies to the synthetic 

organic chemical manufacturing industry (SOCMI) or the OSWRO 

source category. One commenter states that if the EPA believes 

the 1.7 factor is warranted, it should use petroleum refinery 

leak rates as a starting point instead of SOCMI rates. The 

commenter asserts that based on the experience of member 

companies with process units subject to HON connector 

monitoring, commencement of Method 21 monitoring with a leak 

definition of 500 ppm will not reduce emissions by 50 percent, 

as the EPA estimates. This commenter submitted a report that 

concluded there is no statistical difference in average leak 

rates between the initial Method 21 inspections and subsequent 

inspections and that volatile organic compound (VOC) emissions 

from connectors at plants subject to the HON or Miscellaneous 

Organic NESHAP (MON) are far below SOCMI average factor 
Page 41 of 180

estimates. The commenter suggests that sensory methods of 

detecting leaks are adequate and the imposition of Method 21 in 

addition to current practices will not further reduce the number 

of leaks. The commenter asserts that operators are trained to 

recognize hazards associated with leaks using sensory methods

and are expected to take prompt action when leaks occur.

Another commenter asserts that the revised monitoring 

requirements for connectors will not result in substantial, or 

any, HAP emission reductions. The commenter’s assertion is based 

on data obtained from LDAR records of its member facilities, 

where only five connectors were found to have a leak above 500 

ppm out of 10,542 connectors analyzed over the past year. The 

commenter also asserts that the EPA’s assumption of 82-percent 

HAP composition is incorrect, and was taken from an OSWRO NESHAP 

background information document from 1994 which is based on an 

outdated HAP list (i.e., methyl ethyl ketone has since been 

removed). 

Response: The EPA stands by our analysis of emission 

reduction estimates related to connector monitoring for the 

OSWRO source category. 

Regarding the factor used in estimating the leak frequency, 

we increased the connector leak frequency by a factor of 1.7. As 

explained below, we believe it is appropriate to apply this 

factor to the OSWRO source category to account for differences 
Page 42 of 180

in industry-reported and National Enforcement Investigations 

Center (NEIC) measured leak frequencies. In 1999, the NEIC 

published the results of a comparative monitoring study at 17 

petroleum refineries, which showed the percentage of valves 

identified as leaking by NEIC was always higher than the results 

of monitoring conducted by the petroleum refiners.3 This NEIC 

report states that the disparity between the NEIC and company 

results may be attributable to refineries not monitoring in the 

manner prescribed in Method 21 of 40 CFR part 60, Appendix A-7. 

In a subsequent analysis of these results, the NEIC results were 

shown to be higher than the industry results by a factor of at 

least 2.6 at the 99-percent confidence level.4 As the initial 

connector leak frequency used in the analysis of OSWRO connector 

leak emissions was the same as that used in the Uniform 

Standards analysis,

5 which was based on industry–supplied data

for facilities regulated by the MON, we applied a factor to 

account for the differences noted between industry-supplied data 

and NEIC-measured leak frequency data. For the OSWRO analysis,

 

3 U.S. EPA, Office of Enforcement and Compliance Assurance. October 1999. 

Enforcement Alert: Proper Monitoring Essential to Reducing 'Fugitive 

Emissions' Under Leak Detection and Repair Programs.

4 Memorandum from D. Randall, RTI International, to K. Rackley, USEPA. October 

30, 2007. Statistical Analysis of Valve Leak Frequencies Obtained by Industry 

and EPA for Petroleum Refining Process Units.

5 Memorandum from C. Hancy, RTI International, to J. Howard, USEPA. December 

21, 2011. Analysis of Emissions Reduction Techniques for Equipment Leaks. 

This memorandum is available in the docket for this action.
Page 43 of 180

the factor of 1.7 was used rather than 2.6. This 1.7 factor 

represents the 10th percentile of the data set (i.e., 90 percent 

of the NEIC leak frequencies were at least 1.7 times higher than 

the leak frequencies reported by the refineries). This 

conservative factor was chosen, in part, to account for the 

possibility that refineries and OSWRO facilities could leak at 

different rates.

We disagree with the commenter that applying the connector 

leak frequency factor of 1.7 necessitates the use of petroleum 

refinery leak frequency rates. Since the process equipment and 

chemicals used at OSWRO facilities are more similar to those of 

the SOCMI than those at petroleum refineries, we believe it is

appropriate to use SOCMI leak frequencies. Further, the factor 

we applied to the connector leak frequency to account for 

differences noted between industry-supplied and NEIC-measured 

data already accounted for potential differences in leak 

frequencies between petroleum refineries and OSWRO facilities by 

using the more conservative factor of 1.7 than the factor of 2.6 

that would be applied to refinery data. We note that the initial 

leak frequency of 0.36 percent used in the OSWRO analysis is the 

same as that reported by the commenter’s member companies for 

the HON initial monitoring, and we made the conservative 

assumption that the subsequent leak frequency after 

implementation of Method 21 monitoring of connectors would be 
Page 44 of 180

the same as the initial leak frequency. However, we also 

assumed, as we have in other rulemakings, that these leaking 

connectors would be fixed so that the average leak frequency 

over each monitoring cycle would be equal to one-half of the 

subsequent leak frequency (i.e., 0.18 percent). 6

We disagree with the commenter’s claim that the estimated 

emissions per connector used in the EPA’s analysis are too high. 

The leak rates used were based on those reported in the Protocol 

for Equipment Leak Emissions Estimates (EPA-453/R-95-017,

November 1995), which determined these leak rates based on 

screening data from 33 chemical production units and bagging 

data from 22 chemical production units. We consider this to be 

relevant and robust data, and the resulting average leak 

emissions rates are appropriate to use in our analyses. 

We agree with the commenter that the HAP composition used 

in our analyses of 82 percent was taken from the 1994 OSWRO 

NESHAP background information document. The commenter did not 

provide any information to show that another estimate of HAP 

composition would be appropriate, and, without any basis for a 

different value, we have not changed our analyses to include a 

different HAP composition.

 

6

Memorandum from K. Parrish and D. Randall, RTI International, to K. Rackley, 

USEPA. October 30, 2007. Final Impacts Analysis for Regulatory Options for 

Equipment Leaks of VOC in the SOCMI.
Page 45 of 180

Comment: Two commenters dispute the EPA’s assessment of the 

costs to monitor connectors. Specifically, one commenter 

disputes the EPA’s assumed cost of $2.50 per monitored connector 

and outlines the various challenges in monitoring connectors in 

comparison with other types of equipment components. The other 

commenter states that the EPA underestimated the annual 

administrative costs of monitoring connectors and provides their

own estimate of $27,000. Both commenters provide a revised 

analysis of the cost of connector monitoring based on a recent 

study conducted by one company at one facility, and conclude 

that monitoring connectors would cost $6.50 per component and 

$18,139/ton. Another commenter states that the requirement to 

conduct connector monitoring could result in OSWRO facilities 

being forced to hire outside consultants to perform the 

monitoring due to the large number of connectors at each site 

and that the annual monitoring costs for connectors could be the 

same as that for all other monitored components. 

Response: We have considered the commenters’ concerns that 

the estimated connector monitoring costs used in our analysis of 

the costs of an LDAR program, including periodic connector 

monitoring using Method 21, are too low. The two areas in which 

the commenters dispute the estimated connector monitoring costs 

are in the ongoing monitoring costs per connector and the 

estimated annual administrative and reporting costs. Regarding 
Page 46 of 180

ongoing monitoring costs, we do not believe the $2.50 used in 

the EPA’s analysis is an unreasonable estimate of the monitoring 

costs per connector. This estimate is based on an average 

monitoring cost per component of $1.00 to $1.50, and then 

increased to $2.50 to account for industry claims that 

connectors are more difficult than other components to monitor.7

However, to determine how a fee of $6.50 per connector, as 

suggested by the commenters, would affect the cost effectiveness 

of the provisions, we conducted an additional analysis of costs 

of an LDAR program using this value. We note that all monitoring 

costs already assume an outside contractor would be used. 

Regarding the administrative and reporting costs, the submitted 

study includes $27,000 per year for these activities for 

connectors alone. At the labor rates used in the study, this 

equates to 781 hours per year. We do not find this amount of 

time to be reasonable for connector administrative and reporting 

costs, especially considering that connector monitoring may only 

be required once every four years. However, it may be possible 

that our estimate of 50 hours per year at a labor rate of $92.92 

per hour overestimates the labor rate and underestimates the 

amount of time required to complete the necessary administrative 

 

7

Memorandum from K. Parrish and D. Randall, RTI International, to K. 

Rackley, USEPA. October 30, 2007. Final Impacts Analysis for Regulatory 

Options for Equipment Leaks of VOC in the SOCMI.
Page 47 of 180

requirements. Therefore, we conducted an additional analysis of 

the costs of the LDAR program assuming twice as many hours as we 

previously estimated and the labor rates provided by the 

commenter for these administrative actions. Using these more 

conservative values, the incremental cost effectiveness for 

connectors would be $6,825/ton. This incremental cost 

effectiveness is still $7,000/ton of HAP reduced, as was

calculated without the alternate connector monitoring costs. 

Therefore, using these alternative values would not change our 

determination that the costs of the subpart H LDAR program 

(including connector monitoring) are reasonable, given the level 

of HAP emissions reduction that would be achieved, and we are 

finalizing the equipment leak amendments to require subpart H 

LDAR (including connector monitoring) as proposed.

Comment: One commenter states the EPA used several 

assumptions the commenter does not agree with in its estimate of 

emissions from tanks. One is that the EPA overestimated the tank 

throughput. The commenter asserts that, based on data from its

members, the average waste throughput is typically less than 

20,000,000 gallons for each facility, which is much lower than 

the EPA’s estimate of 35,000,000 gallons per facility. The 

commenter also disagrees with the EPA’s assumption that OSWRO 

tanks contain 100-percent HAP, as hazardous wastes processed by 

OSWRO facilities contain a large portion of organic and 
Page 48 of 180

inorganic non-HAP constituents. The commenter estimates that as 

little as 50 percent of the tank constituents are HAP and 

provided a suggested mix of HAP constituents. The commenter also 

states that the EPA’s selection of Houston as the location of 

the model facility is inappropriate because of its average subtropical temperatures, and a location more representative of the 

national average should be selected. The commenter also states 

that the EPA’s use of the default conservation vent pressure 

settings of 0.03 pounds per square inch (psi) and -0.03 psi in 

the calculation of uncontrolled emissions is too low, and actual 

pressure settings for tanks currently subject to the OSWRO Level 

1 control requirements are typically set at 0.5 psi.

This commenter also disputes the EPA’s estimate of the 

costs that would be incurred by facilities to comply with the 

proposed amendments to the vapor pressure thresholds for tank 

control level. The commenter states that contrary to the EPA’s 

assumptions, there are a significant number of sources that 

would require the installation of a new control device or would 

have to upgrade and/or expand their existing control device 

systems to comply with the Control Level 2 standards. The 

commenter asserts that the EPA provided no assessment of whether 

existing control devices are sized to accommodate additional 

vented sources, and control devices are typically not sized with 

significant excess capacity due to economic and space 
Page 49 of 180

considerations. The commenter states that the EPA also did not 

consider flame arrestors to prevent back-flash to tanks, which 

would cost $10,000 per unit. In addition, the commenter asserts 

that the EPA did not consider capital costs related to 

engineering installation, or regulatory and safety costs, such 

as additional process hazard reviews and analyses under either 

the Occupational Safety and Health Administration (OSHA) Process 

Safety Management or CAA Risk Management Plan regulations that 

would likely be required if tanks are connected to a control 

device.

The commenter also disputes EPA’s estimate of annual costs, 

and states that the EPA did not consider the additional cost 

associated with operation of the control device itself, such as 

costs associated with replacement and disposal or regeneration 

of carbon (for a carbon adsorption system). The commenter 

asserts that the annual cost should still be applied even if 

there is an existing control device because annual carbon costs 

are a function of the throughput of the newly affected units. 

The commenter further asserts that additional annual and capital 

costs would be incurred from the operation of a nitrogen 

blanketing system that may be required if carbon adsorption 

units is used as the HAP control device. 

The commenter estimates that the cost effectiveness of the 

proposed amendments to the tank vapor pressure thresholds is 
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actually $48,000 per ton of HAP controlled, which the commenter 

claims is an unnecessary cost to achieve minor emission 

reductions.

Response: Our analysis presented the best quantification of 

the emission reductions and costs of the proposed amendments to 

the tank provisions based on the information available at the 

time. We have revised some of the assumptions used in the 

analysis to address concerns raised by the commenter and to 

include additional information that the commenter has provided. 

Details of this analysis are presented in the memo, Revised 

Technology Review for the Off-Site Waste and Recovery Operations 

Tanks, which is available in the docket for this action.

We agree with the commenter that OSWRO tanks likely do not 

contain 100-percent HAP, and have revised the analysis to 

include a mix of tank constituents that comprises 60-percent 

HAP, as suggested by the commenter. We have moved the location 

of the model facility from Houston to a location near the center 

of the continental United States, which has temperatures more 

representative of the national average. We have also increased 

the conservation vent pressure setting from the default value of 

0.03 psi to 0.5 psi, as suggested by the commenter. We did not 

revise the average waste throughput used in the analysis. The 

commenter did not provide data to support the claim that the 

average waste throughput is actually 20,000,000 gallons per 
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facility, and the EPA’s estimate of 35,000,000 gallons per 

facility is supported by data obtained through the 2013 CAA 

section 114 questionnaire for the one OSWRO facility with tanks 

in the size and vapor pressure range affected by the proposed 

standards.

In addition, while some facilities may have control devices 

with adequate capacity to control emissions from the additional 

tanks that would become subject to Level 2 control requirements 

as a result of the proposed amendments, it may be possible that

some facilities do not have the required excess capacity. 

Therefore, we have revised the analysis to add the conservative 

assumption that each facility would need to install a carbon 

adsorber to comply with the proposed amendments. The revised 

analysis includes the cost of a carbon adsorber canister system, 

including installation and other associated capital costs, as 

well as annual costs for the operation of the device (e.g., cost 

of carbon). We have also revised the analysis to include costs 

for flame arrestors, as suggested by the commenter. We have 

revised the number of tanks in the analysis from 21 to 14 to 

account for seven tanks that are known to already be controlled 

based on information collected through the CAA section 114 

questionnaire. 

We disagree with the commenter that the cost of nitrogen 

blanketing systems should be included in the analysis. Nitrogen 
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blankets are not required by the OSWRO NESHAP for use with a 

control device, and we do not believe that nitrogen blankets are 

necessary for the operation of control devices, including a 

carbon adsorption system, as suggested by the commenter. 

Further, nitrogen blanketing systems can be used on tanks that 

are not controlled by a control device, and may already be in 

place for the tanks that would be affected by the revised 

standard. We also disagree with the commenter that we have not 

considered capital costs related to engineering installation and 

regulatory and safety costs. We explicitly include installation 

costs of equipment, and we follow the procedure of the EPA 

Control Cost Manual for including indirect costs.

Considering the revisions to emission controls and costs 

identified above, we have determined that the capital costs for 

the proposed amendments to the tank provisions are approximately 

$139,000, and the total annualized costs are estimated to be 

approximately $192,000. The estimated HAP emissions reduction is 

approximately 26 tpy, and the cost effectiveness is 

approximately $7,000 per ton of HAP reduced. While the revised 

analysis resulted in lower emission reductions at a higher cost 

than the estimates developed prior to proposal, we still find 

the amendments to the tank control provisions to be cost 

effective, and are, therefore, finalizing the amendments as 

proposed.
Page 53 of 180

4. What is the rationale for our final decisions for the 

technology review?

Based on our revised analysis for tanks, the costs of 

Option 1 are reasonable, given the level of HAP emissions 

reduction that would be achieved with this control option. 

Therefore, as a result of this revised technology review 

pursuant to CAA section 112(d)(6), we have determined, as we did 

at proposal, that it is appropriate to revise the OSWRO NESHAP

to require Level 2 controls for tanks with capacities greater 

than or equal to 75 m3, but less than 151 m3, if the vapor 

pressure of the stored material is 13 kPa or greater.

Considering our revised analysis for equipment leaks, we 

have determined the costs of Option 2, which includes all of the 

requirements of Option 1, are reasonable, given the level of HAP 

emissions reduction that would be achieved with this control 

option. We note that, while we did not include the higher 

connector monitoring costs analyzed in response to commenter 

suggestions in this determination, the inclusion of these costs 

would not change our conclusion that the costs of Option 2 are 

reasonable, given the level of HAP emissions reduction that 

would be achieved with this control option. Therefore, as a 

result of this revised technology review pursuant to CAA section 

112(d)(6), we have determined, as we did at proposal, that it is 

appropriate to revise the OSWRO NESHAP to require existing and 
Page 54 of 180

new affected sources to comply with 40 CFR part 63, subpart H 

rather than 40 CFR part 61, subpart V, including the subpart H 

requirements for connectors in gas/vapor service and in light 

liquid service.

As noted in section IV.A.4 of the preamble, we are 

promulgating these revisions concurrently under section 

112(f)(2) of the CAA to provide an ample margin of safety to 

protect public health. Furthermore, for the reasons discussed 

above and in the preamble to the proposed rule, we have 

determined that it is not necessary pursuant to CAA section 

112(d)(6) to revise the OSWRO NESHAP to require additional HAP 

emission controls for process vents or any other equipment or 

processes at OSWRO facilities. 

C. Startup, Shutdown and Malfunction Provisions for the OSWRO

Source Category

1. What SSM provisions did we propose for the OSWRO source 

category?

In its 2008 decision in Sierra Club v. EPA, 551 F.3d 1019 

(D.C. Cir. 2008), the United States Court of Appeals for the 

District of Columbia Circuit vacated portions of two provisions 

in the EPA’s CAA section 112 regulations governing the emissions 

of HAP during periods of SSM. Specifically, the Court vacated 

the SSM exemption contained in 40 CFR 63.6(f)(1) and 40 CFR 

63.6(h)(1), holding that under section 302(k) of the CAA, 
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emissions standards or limitations must be continuous in nature 

and that the SSM exemption violates the CAA's requirement that 

some CAA section 112 standards apply continuously. 

We have eliminated the SSM exemption in this rule. 

Consistent with Sierra Club v. EPA, the EPA proposed standards 

in this rule that apply at all times. We have also revised Table 

2 (the General Provisions applicability table) in several 

respects as is explained in more detail below. For example, we 

have eliminated the incorporation of the General Provisions’ 

requirement that the source develop an SSM plan. We have also 

eliminated and revised certain recordkeeping and reporting that 

is related to the SSM exemption as described in detail in the 

proposed rule and summarized again here.

In proposing the standards in this rule, the EPA took into 

account startup and shutdown periods and, for the reasons 

explained below, did not propose alternate standards for those 

periods. Information on periods of startup and shutdown received 

from the facilities through CAA section 114 questionnaire 

responses indicated that emissions during these periods are the 

same as during normal operations. The facilities do not process 

waste unless and until their control devices are operating to 

fully control emissions. Therefore, we determined that separate 

standards for periods of startup and shutdown are not necessary.
Page 56 of 180

Periods of startup, normal operations and shutdown are all 

predictable and routine aspects of a source’s operations. 

Malfunctions, in contrast, are neither predictable nor routine. 

Instead they are, by definition, sudden, infrequent and not 

reasonably preventable failures of emissions control, process or 

monitoring equipment. (40 CFR 63.2) (Definition of malfunction).

The EPA interprets CAA section 112 as not requiring emissions 

that occur during periods of malfunction to be factored into 

development of CAA section 112 standards. Under CAA section 112, 

emission standards for new sources must be no less stringent 

than the level “achieved” by the best controlled similar source 

and for existing sources generally must be no less stringent 

than the average emission limitation “achieved” by the best 

performing 12 percent of sources in the category. There is 

nothing in CAA section 112 that directs the EPA to consider 

malfunctions in determining the level “achieved” by the best 

performing sources when setting emission standards. As the 

United States Court of Appeals for the District of Columbia 

Circuit has recognized, the phrase “average emissions limitation 

achieved by the best performing 12 percent of” sources “says 

nothing about how the performance of the best units is to be 

calculated.” Nat'l Ass'n of Clean Water Agencies v. EPA, 734 

F.3d 1115, 1141 (D.C. Cir. 2013). While the EPA accounts for 

variability in setting emission standards, nothing in CAA 
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section 112 requires the EPA to consider malfunctions as part of 

that analysis. A malfunction should not be treated in the same 

manner as the type of variation in performance that occurs 

during routine operations of a source. A malfunction is a 

failure of the source to perform in a “normal or usual manner” 

and no statutory language compels the EPA to consider such 

events in setting CAA section 112 standards.

Further, accounting for malfunctions in setting emission 

standards would be difficult, if not impossible, given the 

myriad different types of malfunctions that can occur across all 

sources in the category and given the difficulties associated 

with predicting or accounting for the frequency, degree and 

duration of various malfunctions that might occur. As such, the 

performance of units that are malfunctioning is not “reasonably” 

foreseeable. See, e.g., Sierra Club v. EPA, 167 F.3d 658, 662 

(D.C. Cir. 1999) (“The EPA typically has wide latitude in 

determining the extent of data-gathering necessary to solve a 

problem. We generally defer to an agency's decision to proceed 

on the basis of imperfect scientific information, rather than to 

‘invest the resources to conduct the perfect study.’”). See also

Weyerhaeuser v. Costle, 590 F.2d 1011, 1058 (D.C. Cir. 1978) 

(“In the nature of things, no general limit, individual permit, 

or even any upset provision can anticipate all upset situations. 

After a certain point, the transgression of regulatory limits 
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caused by ‘uncontrollable acts of third parties,’ such as 

strikes, sabotage, operator intoxication or insanity, and a 

variety of other eventualities, must be a matter for the 

administrative exercise of case-by-case enforcement discretion, 

not for specification in advance by regulation.”). In addition, 

emissions during a malfunction event can be significantly higher 

than emissions at any other time of source operation. For 

example, if an air pollution control device with 99-percent 

removal goes off-line as a result of a malfunction (as might 

happen if, for example, the bags in a baghouse catch fire) and 

the emission unit is a steady state type unit that would take 

days to shut down, the source would go from 99-percent control 

to zero control until the control device was repaired. The 

source’s emissions during the malfunction would be 100 times 

higher than during normal operations. As such, the emissions 

over a 4-day malfunction period would exceed the annual 

emissions of the source during normal operations. As this 

example illustrates, accounting for malfunctions could lead to 

standards that are not reflective of (and significantly less 

stringent than) levels that are achieved by a well-performing 

non-malfunctioning source. It is reasonable to interpret CAA 

section 112 to avoid such a result. The EPA’s approach to 

malfunctions is consistent with CAA section 112 and is a 

reasonable interpretation of the statute.
Page 59 of 180

In the event that a source fails to comply with the 

applicable CAA section 112(d) standards as a result of a 

malfunction event, the EPA would determine an appropriate 

response based on, among other things, the good faith efforts of 

the source to minimize emissions during malfunction periods, 

including preventative and corrective actions, as well as root 

cause analyses to ascertain and rectify excess emissions. The 

EPA would also consider whether the source's failure to comply 

with the CAA section 112(d) standard was, in fact, sudden, 

infrequent, not reasonably preventable and was not instead 

caused in part by poor maintenance or careless operation. 40 CFR 

63.2 (definition of malfunction). 

If the EPA determines in a particular case that an 

enforcement action against a source for violation of an emission 

standard is warranted, the source can raise any and all defenses 

in that enforcement action, and the federal district court will 

determine what, if any, relief is appropriate. The same is true 

for citizen enforcement actions. Similarly, the presiding 

officer in an administrative proceeding can consider any defense 

raised and determine whether administrative penalties are 

appropriate.

In summary, the EPA interpretation of the CAA and, in 

particular, section 112 is reasonable and encourages practices 

that will avoid malfunctions. Administrative and judicial 
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procedures for addressing exceedances of the standards fully 

recognize that violations may occur despite good faith efforts 

to comply and can accommodate those situations.

To address the United States Court of Appeals for the 

District of Columbia Circuit vacatur of portions of the EPA’s 

CAA section 112 regulations governing the emissions of HAP 

during periods of SSM, Sierra Club v. EPA, 551 F.3d 1019 (D.C. 

Cir. 2008), we proposed to revise and add certain provisions to 

the OSWRO rule. As described in detail below, we proposed to 

revise the General Provisions Applicability Table (Table 2) to 

change several references related to requirements that apply 

during periods of SSM. We also proposed to add the following 

provisions to the OSWRO rule: (1) The general duty to minimize 

emissions at all times; (2) the requirement for sources to 

comply with the emission limits in the rule at all times, with 

clarification for what constitutes a deviation; (3) performance 

testing conditions requirements; (4) excused monitoring 

excursions provisions; and (5) malfunction recordkeeping and 

reporting requirements.

i. General Duty

We proposed to revise the General Provisions applicability 

table (Table 2) entry for 40 CFR 63.6(e) by adding rows 

specifically for 40 CFR 63.6(e)(1)(i), 63.6(e)(1)(ii), 

63.6(e)(1)(iii), and 63.6(e)(3) and to include a “no” in the 
Page 61 of 180

column 2 for the 40 CFR 63.6(e)(1)(i) entry. Section 

63.6(e)(1)(i) describes the general duty to minimize emissions. 

Some of the language in that section is no longer necessary or 

appropriate in light of the elimination of the SSM exemption. We 

proposed instead to add general duty regulatory text at 40 CFR 

63.683(e) that reflects the general duty to minimize emissions 

while eliminating the reference to periods covered by an SSM 

exemption. The current language in 40 CFR 63.6(e)(1)(i) 

characterizes what the general duty entails during periods of 

SSM. With the elimination of the SSM exemption, there is no need 

to differentiate between normal operations, startup and 

shutdown, and malfunction events in describing the general duty. 

Therefore, the language the EPA proposed for 40 CFR 63.683(e) 

does not include that language from 40 CFR 63.6(e)(1).

We also proposed to include a “no” in column 2 for the 

newly added entry for 40 CFR 63.6(e)(1)(ii). Section 

63.6(e)(1)(ii) imposes requirements that are not necessary with 

the elimination of the SSM exemption or are redundant with the 

general duty requirement being added at 63.683(e). 

The provisions of 40 CFR 63.6(e)(1)(iii) still apply, and 

we proposed to keep the “yes” in column 2 for that section. For 

40 CFR 63.6(e)(2), we proposed to include a “no” in the second 

column for that section because it is a reserved section in the 

General Provisions.
Page 62 of 180

We also proposed to clarify in the applicability section of 

40 CFR 63.680(g)(1) and (2) that the emission limits of subpart 

DD apply at all times except when the affected source is not 

operating and that the owner or operator must not shut down 

items of equipment required or used for compliance with the 

requirements of subpart DD.

ii. SSM Plan 

We proposed to include a “no” in column 2 for the newly 

added 40 CFR 63.6(e)(3) entry. Generally, this paragraph 

requires development of an SSM plan and specifies SSM 

recordkeeping and reporting requirements related to the SSM 

plan. As noted, the EPA proposed to remove the SSM exemptions. 

Therefore, affected units will be subject to an emission 

standard during such events. The applicability of a standard 

during such events will ensure that sources have ample incentive 

to plan for and achieve compliance and thus the SSM plan 

requirements are no longer necessary.

iii. Compliance With Standards 

We proposed to revise the General Provisions applicability 

table (Table 2) entry for 40 CFR 63.6(f)(1) by changing the 

“yes” in column 2 to a “no.” The current language of 40 CFR 

63.6(f)(1) exempts sources from non-opacity standards during 

periods of SSM. As discussed above, the Court in Sierra Club

vacated the exemptions contained in this provision and held that 
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the CAA requires that some section 112 standards apply 

continuously. Consistent with Sierra Club, the EPA proposed to 

revise the standards in this rule to apply at all times.

iv. Performance Testing

We proposed to revise the General Provisions applicability 

table (Table 2) entry for 40 CFR 63.7(e)(1) by changing the 

“yes” in column 2 to a “no.” Section 63.7(e)(1) describes 

performance testing requirements. The EPA instead proposed to 

add a performance testing requirement at 40 CFR 63.694(l). The

performance testing requirements we proposed to add differ from 

the General Provisions performance testing provisions in several 

respects. The regulatory text does not include the language in 

40 CFR 63.7(e)(1) that restated the SSM exemption and language 

that precluded startup and shutdown periods from being 

considered “representative” for purposes of performance testing. 

The proposed performance testing provisions specified that

performance tests conducted under this subpart should be based 

on representative performance (i.e., performance based on normal 

operating conditions) of the affected source. As in 40 CFR 

63.7(e)(1), performance tests conducted under this subpart 

should not be conducted during malfunctions because conditions 

during malfunctions often are not representative of normal 

operating conditions. The EPA proposed to add language that

requires the owner or operator to record the process information 
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that is necessary to document operating conditions during the 

test and include in such record an explanation to support that 

such conditions represent normal operation. Section 63.7(e)

requires that the owner or operator make available to the 

Administrator such records “as may be necessary to determine the 

condition of the performance test” upon request, but does not 

specifically require the information to be recorded. The

regulatory text the EPA proposed to add to this provision builds 

on that requirement and makes explicit the requirement to record 

the information.

v. Monitoring

We proposed to revise the General Provisions applicability 

table (Table 2) entries for 40 CFR 63.8(c)(1)(i) and (iii) by 

changing the “yes” in column 2 to a “no.” The cross-references 

to the general duty and SSM plan requirements in those 

subparagraphs are not necessary in light of other requirements 

of 40 CFR 63.8 that require good air pollution control practices 

(40 CFR 63.8(c)(1)) and that set out the requirements of a 

quality control program for monitoring equipment (40 CFR 

63.8(d)).

vi. Recordkeeping

We proposed to revise the General Provisions applicability 

table (Table 2) entry for 40 CFR 63.10(b)(2)(i) by changing the

“yes” in column 2 to a “no.” Section 63.10(b)(2)(i) describes 
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the recordkeeping requirements during startup and shutdown. 

These recording provisions are no longer necessary because the 

EPA proposed that recordkeeping and reporting applicable to 

normal operations will apply to startup and shutdown. In the 

absence of special provisions applicable to startup and 

shutdown, such as a startup and shutdown plan, there is no 

reason to retain additional recordkeeping for startup and 

shutdown periods.

We proposed to revise the General Provisions applicability 

table (Table 2) entry for 40 CFR 63.10(b)(2)(ii) by changing the 

“yes” in column 2 to a “no.” Section 63.10(b)(2)(ii) describes 

the recordkeeping requirements during a malfunction. The EPA

proposed to add such requirements to 40 CFR 63.696(h). The 

regulatory text we proposed to add differs from the General 

Provisions it is replacing in that the General Provisions 

require the creation and retention of a record of the occurrence 

and duration of each malfunction of process, air pollution

control and monitoring equipment. The EPA proposed that this 

requirement apply to any failure to meet an applicable standard 

and is requiring that the source record the date, time and

duration of the failure rather than the “occurrence.” The EPA 

also proposed to add to 40 CFR 63.696(h) a requirement that 

sources keep records that include a list of the affected source

or equipment and actions taken to minimize emissions, an 
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estimate of the quantity of each regulated pollutant emitted 

over the standard for which the source failed to meet the 

standard, and a description of the method used to estimate the 

emissions. Examples of such methods would include product-loss

calculations, mass balance calculations, measurements when

available, or engineering judgment based on known process 

parameters. The EPA proposed to require that sources keep 

records of this information to ensure that there is adequate

information to allow the EPA to determine the severity of any 

failure to meet a standard, and to provide data that may 

document how the source met the general duty to minimize 

emissions when the source has failed to meet an applicable 

standard.

We proposed to revise the General Provisions applicability 

table (Table 2) entry for 40 CFR 63.10(b)(2)(iv) by changing the 

“yes” in column 2 to a “no.” When applicable, the provision 

requires sources to record actions taken during SSM events when 

actions were inconsistent with their SSM plan. The requirement 

is no longer appropriate because SSM plans will no longer be 

required. The requirement previously applicable under 40 CFR 

63.10(b)(2)(iv)(B) to record actions to minimize emissions and 

record corrective actions is now applicable by reference to 40 

CFR 63.696(h).
Page 67 of 180

We proposed to revise the General Provisions applicability 

table (Table 2) entry for 40 CFR 63.10(b)(2)(v) by changing the 

“yes” in column 2 to a “no.” When applicable, the provision 

requires sources to record actions taken during SSM events to 

show that actions taken were consistent with their SSM plan. The 

requirement is no longer appropriate because SSM plans will no 

longer be required.

vii. Reporting

We proposed to revise the General Provisions applicability 

table (Table 2) entry for 40 CFR 63.10(d)(5)(i) by consolidating 

it with the entry for 63.10(d)(5)(ii) and changing the “yes” in 

column 2 to “no.” Section 63.10(d)(5)(i) describes the reporting 

requirements for SSM. To replace the General Provisions 

reporting requirements, the EPA proposed to add reporting 

requirements to 40 CFR 63.697(b)(3). The replacement language 

differs from the General Provisions requirement in that it 

eliminates periodic SSM reports as a stand-alone report. We 

proposed language that requires sources that fail to meet an 

applicable standard at any time to report the information 

concerning such events in the semiannual summary report already 

required under this rule. We proposed that the report must 

contain the number, date, time, duration and the cause of such 

events (including unknown cause, if applicable), a list of the 

affected source or equipment, an estimate of the quantity of 
Page 68 of 180

each regulated pollutant emitted over any emission limit and a 

description of the method used to estimate the emissions.

Examples of such methods would include product-loss 

calculations, mass balance calculations, measurements when 

available or engineering judgment based on known process 

parameters. The EPA proposed this requirement to ensure that 

there is adequate information to determine compliance, to allow 

the EPA to determine the severity of the failure to meet an 

applicable standard, and to provide data that may document how 

the source met the general duty to minimize emissions during a 

failure to meet an applicable standard. 

We will no longer require owners or operators to determine 

whether actions taken to correct a malfunction are consistent 

with an SSM plan, because plans would no longer be required. The

proposed amendments, therefore, eliminated the cross reference 

to 40 CFR 63.10(d)(5)(i) that contains the description of the 

previously required SSM report format and submittal schedule 

from this section. These specifications are no longer necessary 

because the events will be reported in otherwise required 

reports with similar format and submittal requirements.

We proposed to revise the General Provisions applicability 

table (Table 2) entry for 40 CFR 63.10(d)(5)(ii) by 

consolidating it with the entry for 63.10(d)(5)(i) and changing 

the “yes” in column 2 to a “no.” Section 63.10(d)(5)(ii) 
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describes an immediate report for startups, shutdown and 

malfunctions when a source failed to meet an applicable standard 

but did not follow the SSM plan. We will no longer require 

owners and operators to report when actions taken during a 

startup, shutdown or malfunction were not consistent with an SSM 

plan, because plans would no longer be required.

2. How did the SSM provisions change for the OSWRO source 

category?

We have not changed any aspect of the SSM provisions since 

the proposal.

3. What key comments did we receive on the SSM provisions, and 

what are our responses?

Comments were received regarding the proposed revisions to 

remove the SSM exemptions for the OSWRO source category. Some 

commenters suggested that the rule should provide a six-month 

compliance period for the SSM provisions, that the rule 

requirements, which were based on steady-state conditions,

should not apply during periods of malfunction, and that the EPA 

should establish work practice standards for malfunctions. One 

commenter generally supported the revised provisions for the 

emission standards in the OSWRO NESHAP to apply at all times but 

suggested that more stringent monitoring, recordkeeping, 

reporting and notification requirements are needed for 

malfunctions. The commenters did not provide new information or 
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a basis for EPA to change the proposed provisions and did not 

provide sufficient information to show that facilities cannot 

comply with the MACT standards at all times, including periods 

of startup, shutdown and malfunction. The comments and our 

specific responses to those comments can be found in the Comment 

Summary and Response document available in the docket for this 

action (EPA–HQ–OAR–2012–0360).

4. What is the rationale for our final decisions for the SSM 

provisions?

For the reasons provided above, provided in the preamble 

for the proposed rule and provided in the comment summary and 

response document available in the docket, we have removed the 

SSM exemption from the OSWRO NESHAP; eliminated or revised 

certain recordkeeping and reporting requirements related to the 

eliminated SSM exemption; and removed or modified inappropriate, 

unnecessary or redundant language in the absence of the SSM 

exemption. We are, therefore, finalizing our proposed 

determination that facilities comply with the standards at all 

times and no additional standards are needed to address 

emissions during startup or shutdown periods.

D. Other Changes Made to the OSWRO NESHAP 

1. What other changes did we propose for the OSWRO NESHAP?

i. Electronic Reporting
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As stated in the preamble to the proposed rule, to increase 

the ease and efficiency of data submittal and data 

accessibility, the EPA proposed to require owners and operators 

of OSWRO facilities to submit electronic copies of certain 

required performance test reports. 

Data will be collected by direct computer-to-computer 

electronic transfer using EPA-provided software. This EPAprovided software is an electronic performance test report tool 

called the ERT. The ERT will generate an electronic report 

package which will be submitted to the Compliance and Emissions 

Data Reporting Interface (CEDRI) and then archived to the EPA’s 

Central Data Exchange (CDX). A description and instructions for 

use of the ERT can be found at 

http://www.epa.gov/ttn/chief/ert/index.html and CEDRI can be 

accessed through the CDX Web site (http://www.epa.gov/cdx).

The requirement to submit performance test data 

electronically to the EPA will not create any additional 

performance testing and will apply only to those performance 

tests conducted using test methods that are supported by the 

ERT. A listing of the pollutants and test methods supported by 

the ERT is available at the ERT Web site. The EPA believes, 

through this approach, industry will save time in the 

performance test submittal process. Additionally, this 

rulemaking benefits industry by reducing recordkeeping costs as 
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the performance test reports that are submitted to the EPA using 

CEDRI will no longer be required to be kept in hard copy.

State, local and tribal agencies may benefit from more 

streamlined and accurate review of performance test data that 

will become available to the public through WebFIRE. Having such 

data publicly available enhances transparency and 

accountability. For a more thorough discussion of electronic 

reporting of performance tests using direct computer-to-computer 

electronic transfer and using EPA-provided software, see the 

discussion in the preamble to the proposal.

In summary, in addition to supporting regulation 

development, control strategy development and other air 

pollution control activities, having an electronic database 

populated with performance test data will save industry, state, 

local, tribal agencies and the EPA significant time, money and 

effort while improving the quality of emission inventories and 

air quality regulations and providing greater transparency to 

the public.

ii. Routine Maintenance

The OSWRO NESHAP at 40 CFR 63.693(b)(3)(i) allows a 

facility to bypass control devices for up to 240 hours per year 

to perform planned routine maintenance of the closed-vent system 

or control device in situations when the routine maintenance 
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cannot be performed during periods that the control device is 

shut down. 

The routine maintenance provision was originally 

established in the HON (see 40 CFR 63.119(e)(3)–(4); 57 FR 

62710, December 31, 1992 (proposed); 59 FR 19402, April 22, 1994 

(final)) for facilities that elected to use a closed vent system 

and control device to comply with the emission limitation 

requirements for tanks. We included the routine maintenance 

provision in the HON for tanks routing emissions to control 

devices because the estimated HAP emissions to degas the tank 

would be greater than the emissions that would result if the 

tank emitted directly to the atmosphere for a short period of 

time during routine maintenance of the control device.

We intended for the OSWRO NESHAP to track the HON 

maintenance provisions, and, therefore, those provisions should 

have been limited to tanks. We did not identify a basis for 

applying the routine maintenance provisions in the OSWRO NESHAP 

to emission points other than tanks, and, therefore, proposed to 

limit the provision to tanks routing emissions to a control 

device, consistent with the rationale provided in the HON.

iii. Open-Ended Valves and Lines

The OSWRO NESHAP at 40 CFR 63.691(b) requires an owner or 

operator to control emissions from equipment leaks according to 

the requirements of either 40 CFR part 61, subpart V or 40 CFR 
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part 63, subpart H.8 For OELs, both subpart V in 40 CFR 61.242-

6(a) and subpart H in 40 CFR 63.167(a) require that the open end 

be equipped with a cap, blind flange, plug or second valve that 

shall “seal the open end.” However, “seal” is not defined in

either subpart, leading to uncertainty for the owner or operator 

as to whether compliance is being achieved. Inspections under 

the EPA’s Air Toxics LDAR initiative have provided evidence that 

while certain OELs may be equipped with a cap, blind flange, 

plug or second valve, they are not operating in a “sealed” 

manner as the EPA interprets that term.

In response to this uncertainty, we proposed to amend 40 

CFR 63.691(b) to clarify what “seal the open end” means for 

OELs. The proposed clarification explains that, for the purpose 

of complying with the requirements of 40 CFR 61.242-6(a)(2) of 

subpart V or 40 CFR 63.167(a)(2) of subpart H, as applicable, 

OELs are “sealed” by the cap, blind flange, plug or second valve 

when instrument monitoring of the OELs conducted according to 

Method 21 of 40 CFR part 60, appendix A indicates no readings of

500 ppm or greater.

 

8 As discussed in sections III.A, III.B, IV.A and IV.B of this preamble, we 

are removing the option from subpart DD to comply with 40 CFR part 61, 

subpart V for equipment leaks and are requiring compliance with 40 CFR part 

63, subpart H. The compliance date for existing sources is 1 year from the 

effective date of the final amendments, and new sources must comply 

immediately upon the effective date of the final amendments, or upon startup, 

whichever is later.
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In addition, 40 CFR 63.167(d) of subpart H and 40 CFR 

61.242–6(d) of subpart V exempt OELs that are in an emergency 

shutdown system, and which are designed to open automatically, 

from the requirements to be equipped with a cap, blind flange, 

plug or second valve that seals the open end. We proposed that 

these OELs be equipped with either a flow indicator or a seal or 

locking device. We also proposed recordkeeping and reporting 

requirements for these OELs.

iv. Safety Devices, Pressure Tanks, Bypasses and PRDs

To ensure the OSWRO MACT standards are consistent with the 

Sierra Club decision, we proposed to remove the SSM exemption 

from the rule. In addition, in order for our treatment of 

malfunction-caused releases to the atmosphere to conform with 

the reasoning of the Court’s ruling, we proposed to add a 

provision that releases of HAP listed in Table 1 of 40 CFR part 

63, subpart DD directly to the atmosphere from PRDs and closure 

devices on pressure tanks in off-site material service are 

prohibited. We also proposed to prohibit bypasses that divert a 

process vent or closed vent system stream to the atmosphere such 

that it does not first pass through an emission control device, 

except to perform planned routine maintenance of the closed-vent 

system or emission control device for tanks, as discussed in 

section IV.D.3 of this preamble. We further proposed to require 

owners or operators to keep records and report any bypass and 
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the amount of HAP released to the atmosphere with the next 

periodic report. In addition, to add clarity to these 

provisions, we proposed to add definitions for “bypass,” 

“pressure release,” “pressure relief device or valve,” “in 

gas/vapor service,” “in light liquid service,” “in heavy liquid 

service” and “in liquid service” to 40 CFR part 63, subpart DD. 

We also proposed to remove the definition of “safety device” and 

the provisions related to safety devices from 40 CFR part 63, 

subpart DD, which would overlap with and be redundant of parts 

of the proposed definition of “pressure relief device or valve” 

and the provisions related to these devices. 

To ensure compliance with these provisions, we also 

proposed that facilities subject to the OSWRO NESHAP monitor 

PRDs in off-site material service that release to the atmosphere 

by using a device or system that is capable of identifying and 

recording the time and duration of each pressure release and 

notifying operators immediately that a pressure release is 

occurring. Owners or operators would be required to keep records 

and report any pressure release and the amount of organic HAP 

released to the atmosphere with the next periodic report. As 

with the prohibition, this proposed monitoring requirement would

not apply to PRDs for which HAP releases are captured and routed 

to a drain system, process or control device.
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For purposes of estimating the costs of the proposed 

requirement to monitor HAP releases to the atmosphere from PRDs, 

we assumed that operators would install electronic indicators on 

each PRD in off-site material service that vents to the 

atmosphere (rather than to a control device, process or drain 

system) to identify and record the time and duration of each 

pressure release. However, the proposed requirements allowed

owners or operators to use a range of methods to satisfy these 

requirements, including the use of a parametric monitoring 

system (that may already be in use at facilities) on the process 

system or piping that is sufficient to notify operators 

immediately that a release is occurring, as well as recording 

the time and duration of the pressure release. Based on our 

conservative cost assumptions that the most expensive approach 

would be used, the nationwide capital cost of installing these 

monitors was estimated to be $1.75 million, and the total 

annualized cost of installing and operating these monitors is 

$250,000 per year for the OSWRO source category.

v. Performance Test Method Clarifications and Alternative 

Methods

The OSWRO NESHAP at 40 CFR 63.694 specifies test methods 

and procedures to be used in determining compliance with the 

requirements of subpart DD. We proposed several minor changes to 
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these provisions to correct errors and to provide consistency, 

clarification and flexibility. These proposed changes included:

 Requiring that test runs last “at least 1 hour,”

rather than stating that tests last “1 hour” in § 63.694(f)(1) 

and (i)(1);

 Specifying that a minimum of three test runs are

required in § 63.694(l)(3)(i) and (l)(4)(i), consistent with the 

Part 63 General Provisions and standard testing practices;

 Specifying in § 63.694(m)(2) that in the determination 

of process vent stream flow rate and total HAP concentration, 

the sample site selected must be at the center of the vent for 

vents smaller than 0.10 meter in diameter, which is the point 

most likely to provide a representative sample of the gas 

stream;

 Clarifying in § 63.694(j)(3) that results from direct 

measurement must be used as the maximum HAP vapor pressure for 

off-site material in a tank if the Administrator and the owner 

or operator disagree on a determination of the maximum HAP vapor 

pressure for an off-site material stream using knowledge;

 Correcting a citation in § 63.694(k)(3) to the 

appropriate section of EPA Method 21 for instrument response 

factors;
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 Allowing the use of either EPA Method 25A or Method 18

in § 63.694(l)(3) for determining compliance with the control 

device percent reduction requirement and in § 63.694(l)(4) for 

determining compliance with the enclosed combustion device 

concentration limit and clarifying that Method 25A must be used 

when measuring total organic compounds, while Method 18 must be

used for measuring the total HAP compounds included in Table 1 

to the OSWRO NESHAP; 

 Including the use of EPA Method 3A as an alternative 

to EPA Method 3B in § 63.694(l)(4)(iii)(A) for determining the 

oxygen concentration to use in oxygen correction equations; and

 Including the use of EPA Methods 2F and 2G as options 

for flow rate measurement in § 63.694(l)(2) and (m)(3), which 

are newer velocity measurement methods that were published after 

the original OSWRO rule. 

vi. Other Clarifications and Corrections

We proposed several miscellaneous minor changes to improve 

the clarity of the OSWRO NESHAP requirements. These proposed 

changes included:

 Updating the list of combustion devices in 

§ 63.684(b)(5) that may be used to destroy the HAP contained in 

an off-site material stream. This revision would include 

incinerators, boilers or industrial furnaces for which the owner 

or operator complies with the requirements of 40 CFR part 63, 
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subpart EEE, which had not been promulgated when the OSWRO MACT 

standards were developed. We also proposed conforming changes to 

the boiler and process heater control device requirements to 

clarify that combustion units complying with the requirements of 

subpart EEE may be used for the purposes of compliance with the 

OSWRO NESHAP.

 To clarify the requirements for tanks of all sizes and 

tank content vapor pressures, we proposed to revise the tank 

control level tables to include tanks less than 75 m3 in capacity

with a vapor pressure less than 76.6 kPa along with the 

requirements for tanks of other sizes and vapor pressures, and 

we proposed to remove the requirements for these tanks from the 

text of § 63.685(b)(4). 

 Clarifying that where § 63.691 requires the owner or 

operator to control the HAP emitted from equipment leaks in 

accordance with either 40 CFR part 61, subpart V or 40 CFR part 

63, subpart H, the definitions in 40 CFR 61.241 and 40 CFR 

63.161 apply, with the differences listed, for the purposes of

the OSWRO NESHAP.

 Revising the clerical errors to insert ppm values in 

the requirements where they were omitted. These revisions 

included clarifying in § 63.683(c)(1)(ii) that the average

volatile organic HAP (VOHAP) concentration of the off-site

material must be less than 500 parts per million by weight 
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(ppmw) at the point-of-delivery and clarifying the requirements 

of § 63.693(f)(1)(i)(B) and § 63.693(f)(1)(ii)(B) are to achieve 

a total incinerator outlet concentration of less than or equal 

to 20 500 parts per million by volume (ppmv) on a dry basis

corrected to 3-percent oxygen. 

 Clarifying in §§ 63.684(h), 63.693(b)(8) and 

63.694(b)(3)(iv) that the Administrator may require a

performance test, revisions to a control device design analysis, 

or that direct measurement be used in the determination of a 

VOHAP concentration, rather than that the Administrator may only 

request such actions.

 Revising several references to the Part 63 General 

Provisions in Table 2 to correct errors, including errors where

the entries in Table 2 conflict with the regulatory text in 

subpart DD and where references to specific sections of the 

General Provisions do not exist or are reserved.

2. How did the provisions regarding these other proposed changes 

to the OSWRO NESHAP change since proposal?

We have not made any changes to the proposed provisions for 

electronic reporting, routine maintenance, OELs, the proposed 

performance test method clarifications and alternative methods 

or the other proposed clarifications and corrections. 

For PRDs, in the PRD monitoring requirements at 40 CFR 

63.691(c)(3)(i), we are including examples of parametric
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monitoring systems, in addition to the direct monitoring device 

examples listed at proposal. We are also clarifying that tank 

conservation vents are not PRDs in 40 CFR 63.685(c)(2)(iii)(B), 

and we are adding fuel gas systems to the list of equipment a 

PRD may be routed to in 40 CFR 63.691(c)(4) to be exempt from 

the PRD monitoring requirements and pressure release 

prohibition. In addition to these revisions, we are making the 

following revisions, clarifications and corrections in the final 

rule:

 Revisions

o We are revising the language in 40 CFR 63.680(b)(2)(v) 

to indicate that facilities complying with the 

wastewater provisions under any other CAA part 63

regulation, not just the HON, are not required to also 

comply with the OSWRO NESHAP provisions for that 

waste.

o We are revising the requirements for boilers and 

process heaters and also for incinerators in 40 CFR 

63.693(f)(2)(iii) and 63.693(g)(2)(i)(C) to exclude 

such equipment that has been issued a final or interim 

status RCRA permit from the OSWRO NESHAP performance 

test requirements, since the performance tests 

required under RCRA to obtain a permit satisfy the 

performance test requirements of the OSWRO NESHAP.
Page 83 of 180

o We are revising three additional references to the 

Part 63 General Provisions in Table 2 to correct 

errors where the entries in Table 2 conflict with the

regulatory text in subpart DD regarding notification 

of performance tests. The specific changes were to 

revise the entries for 63.7(b), 63.7(c) and 63.9(e) 

from a "no" to a "yes" in column 2 of Table 2.

 Clarifications

o We are revising the definitions of “in gas/vapor 

service” and “in light liquid service” in 40 CFR 

63.681 to clarify our intent that equipment in offsite material service that "contains or contacts” a

gas or vapor is “in gas/vapor service.” For 

consistency, we are also revising the definition of 

“in light liquid service” to include equipment that 

“contains or contacts” liquid.

o To improve clarity we are revising the wording of the 

proposed tank provisions in 40 CFR 63.685(g)(2) to 

remove a repeated phrase.

o We have rephrased the proposed requirements in 40 CFR 

63.694(l) to more simply state that performance tests 

must be conducted under representative performance 

(i.e., performance based on normal operating 

conditions).
Page 84 of 180

o We have added language in 40 CFR 63.691(b)(2)(v) to 

clarify which requirements apply to PRDs in liquid 

service and to clarify when the PRD provisions of 40 

CFR 63.691(c) apply rather than the PRD provisions of 

40 CFR part 63, subpart H or 40 CFR part 61, subpart 

V.

 Corrections

o We are revising 40 CFR 63.680(e)(1)(i) through (iii) 

and 63.680(e)(2) to reference 63.691(b)(2) rather than 

63.691(b) to indicate that compliance with 40 CFR part 

63, subpart H is required after a specified date. 

Consistent with our intention discussed in the 

preamble to the proposed rule, this correction will 

allow compliance with 40 CFR part 61, subpart V only 

until the date at which compliance with 40 CFR part 

63, subpart H is required. 

o We are including the correct VOHAP concentration of 

500 ppmw in 40 CFR 63.683(c)(1)(ii).

o We are correcting an erroneous reference to 40 CFR 

part 67 in 40 CFR 63.685(c)(2)(iii)(B) to properly 

reference 40 CFR part 63. 

o We are adding a reference in the semiannual reporting 

requirements of 40 CFR 63.697(b)(4) to 40 CFR 
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63.683(f), which includes additional deviations that 

must be reported.

o We are correcting three entries in the General 

Provisions Applicability table

3. What key comments did we receive on the other changes to the 

OSWRO NESHAP, and what are our responses?

Several comments were received regarding the proposed 

revisions to the ERT, OELs, PRDs and other provisions for the 

OSWRO source category. The following is a summary of several of 

these comments and our response to those comments. Other 

comments received and our responses to those comments can be

found in the Comment Summary and Response document available in 

the docket for this action (EPA–HQ–OAR–2012–0360).

i. Electronic Reporting

Comment: One commenter notes that requiring electronic 

reporting to the EPA does not increase the ease and efficiency 

of data submittal for the regulated community because state 

agencies also want the reports submitted to them in their own 

standard format. The commenter requests that the EPA work with 

air agencies to provide a one-stop location for submittal of air 

emissions testing results. 

Response: The EPA continues to work with air agencies as 

well as stack testing companies (who typically prepare test 

reports) to develop the ERT. E-Enterprise is an EPA-state 
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initiative to improve environmental performance and enhance 

services to the regulated community, environmental agencies and 

the public. We currently have active E-Enterprise projects 

related to electronic reporting that involve several states, and 

we are actively seeking input from all states willing to 

participate in such projects with EPA. The current ERT was 

designed to accept data and information that is typically 

collected during a performance test. Some air agencies have 

begun accepting the ERT as their reporting mechanism, and with 

experience, we believe acceptance by other air agencies will 

increase. CEDRI, the portal through which this data is submitted 

to CDX, includes the ability for states to interact with 

submitted ERT files directly, immediately after electronic 

submission. During the first phase in the development of CEDRI, 

we initiated a multi-disciplinary, cross-functional Integrated 

Project Team (IPT) consisting of EPA personnel from various 

offices and representatives from air agencies. The objectives of 

the CEDRI IPT were to gain insight and ideas regarding the data 

flow process within the CEDRI. States have the ability to 

access files in CEDRI as soon as they are submitted and can 

review these documents from anywhere that has internet access. 

While in some instances air agencies may still want a hard copy 

of a test report, the ERT can generate a printed test report or 

export the report to a word processor for reformatting. This 
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report can be generated by an air agency with an ERT they have

opened, or generated by a regulated entity and submitted to the 

air agency as an emissions test report. 

The EPA believes that electronic reporting is a more 

efficient way to collect test data and has set up a retrieval 

system such that air agencies can access files that have been 

submitted using the ERT. As more air agencies adopt electronic 

reporting, we believe that the need for paper reports will 

diminish. The EPA is also developing a web-based ERT and has 

plans to release an extensible markup language (XML) schema that 

could be used by third parties to develop customized reporting 

software that meets the EPA’s reporting requirements. The EPA 

expects these additional reporting options will provide a more 

robust and user friendly reporting process in the future.

ii. Open-Ended Valves and Lines

Comment: One commenter states that the OEL provisions are 

“equipment standards,” and compliance is determined by whether a 

cap, blind flange, plug or second valve is physically installed, 

and the term “sealed” historically has meant one of these 

devices is present. 

Response: The EPA disagrees with the commenter. The EPA’s 

intent has always been that caps, blind flanges, plugs or second 

valves that are installed on OELs provide a seal, i.e., no 

detectable emissions. This is further supported by examples of 
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compliance audits conducted by the EPA’s Office of Enforcement 

and Compliance Assurance (OECA) and EPA Regional enforcement 

personnel in which companies were cited for OELs not being 

sealed. We have placed these audits in the docket for this 

action.

Comment: Two commenters believe the EPA must show that 

imposing a new emissions limit for OELs is justified according 

to the criteria of CAA section 112(d)(6), including the 

technical feasibility, potential emission reductions and cost 

effectiveness. The commenters state that the EPA failed to 

provide new data or rationale showing that the definition of 

“seal” is needed for compliance assurance or to relieve 

regulatory uncertainty, relying only on enforcement inspections 

referenced in the 2007 40 CFR part 61, subpart VV rulemaking in 

which monitoring OELs was determined to not be cost effective 

and was not the best demonstrated technology (BDT). Another 

commenter states that the EPA did not provide any data specific 

to the OSWRO source category for OELs, and the data that were

provided did not include the concentration detected, whether the 

measurements were for HAP or VOCs, or what standardization 

chemicals were used. One commenter states that the existence of 

leaks from OELs is low and notes that while the EPA did not 

request information to support monitoring of OELs, the commenter 

referred to a monitoring study its member performed for OELs 
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showing that less than 1 percent of OELs were leaking at rates 

of 500 ppm or greater. Another commenter states that the EPA’s 

proposed definition for a “seal” is actually a new loophole that 

would exempt leaks from OELs below 500 ppm from the standards. 

The commenter contends this definition is another type of 

exemption similar to the SSM exemption the United States Court 

of Appeals for the District of Columbia Circuit found unlawful, 

and the EPA should not finalize the definition as proposed.

Response: The EPA disagrees with the commenters that we are 

imposing a new emissions limit for OELs. As discussed in the 

preamble for the proposed rule and summarized above, the 

existing OSWRO NESHAP already requires the open end of OELs to 

be equipped with a cap, blind flange, plug or second valve that 

shall “seal the open end.” In response to compliance uncertainty 

for owners and operators, we are amending 40 CFR 63.691(b) to 

clarify that, for the purpose of complying with the requirements 

of subpart H or subpart V, as applicable9, OELs are “sealed” by 

the cap, blind flange, plug or second valve when instrument 

monitoring of the OEL conducted according to Method 21 of 40 CFR 

 

9 As discussed in sections III.A, III.B, IV.A and IV.B of this preamble, we 

are removing the option from subpart DD to comply with 40 CFR part 61, 

subpart V for equipment leaks and are requiring compliance with 40 CFR part 

63, subpart H. The compliance date for existing sources is 1 year from the 

effective date of the final amendments, and new sources must comply 

immediately upon the effective date of the final amendments, or upon startup, 

whichever is later.
Page 90 of 180

part 60, appendix A indicates no readings of 500 ppm or greater.

This is consistent with how we have interpreted the term “seal” 

during inspections and, contrary to the commenters’ assertions, 

is not a new requirement. As demonstrated by the data provided 

in the docket and the commenter’s data showing that about 1

percent of all OELs are leaking, OELs are not uniformly 

operating in a “sealed” manner by keeping emissions below the 

500 ppm threshold. The commenters have not identified a reason

to conclude that the OEL data provided in the docket are not 

representative of the OSWRO source category. With this 

clarification, the EPA is removing any ambiguity regarding what 

constitutes a “sealed” OEL.

The EPA also disagrees with the commenter that clarifying 

the meaning of “seal” creates a new loophole for OELs. As 

discussed in the preamble to the proposed rule and elsewhere in 

this document, we are clarifying an existing requirement that 

OELs be sealed.

iii. PRDs

Comment: Several commenters state or suggest that PRDs are 

safety devices, and these requirements will ask plant operators 

to choose between safety and committing a violation. Two of 

these commenters claim that this position is in direct contrast 

to the General Duty provisions, which state that, “at all times, 

the owner or operator must operate and maintain any affected 
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source, including associated air pollution control equipment and 

monitoring equipment, in a manner consistent with safety and 

good air pollution control practices for minimizing 

emissions...” Two other commenters state that the proposed rule 

would require that PRD emissions be vented to a control device, 

which could reduce the effectiveness of PRD by not allowing 

over-pressure from the tank or process unit to vent quickly 

enough to prevent damage. One commenter asserts that an OSHA 

Process Safety Management Review would indicate that venting a 

PRD to a control device would create an unacceptable risk. 

Further, one commenter argues that the requirements will assign 

the same level of importance to minor releases as to significant 

releases that require immediate attention, which will divert 

resources from critical safety tasks. 

One commenter states that the proposed PRD monitoring 

requirements will predetermine the imposition of systems that 

safety experts may deem unnecessary, and the placement of such 

systems, including monitoring, should rather be determined 

during a process hazards analysis, which is specific to each 

situation and is implemented for the explicit purpose of 

protecting life and property. Another commenter also argues that 

process safety professionals should make risk-based decisions, 

and asserts that the proposed requirements do not recognize the 

variations that exist between different types of systems and 
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that choices must be made for each individual system considering 

site conditions. The commenter asserts that the management 

requirements for PRDs should have a wide variety of options 

depending on the character of the discharge. The commenter 

states that the industry’s success in preventing accidents has 

lead the EPA to wrongly assume that it is easy to anticipate and 

prevent all circumstances that may cause an over-pressurization 

event.

Response: The EPA disagrees with the commenters that we are 

forcing plant operators to choose between safety and committing 

a violation. We recognize that industry has stated that they 

believe releases from PRDs sometimes occur in order to protect 

systems from failures that could endanger worker safety and the 

systems that the PRDs are designed to protect. The PRD 

requirements were established with the recognition that emission 

releases to the atmosphere from these devices occur only in the 

event of unplanned and unpredictable events. When PRD releases 

are due to malfunctions, the EPA would determine an appropriate 

response based on, among other things, the good faith efforts of 

the source to minimize emissions, including preventative and 

corrective actions, as well as root cause analyses to ascertain 

and rectify excess emissions. This approach is consistent with 

the General Duty provisions and is designed to minimize 
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emissions while recognizing that these events may be unavoidable 

even in a well-designed and maintained system. 

We disagree with the comment that minor releases will 

divert attention and resources away from critical safety tasks.

These releases are associated with malfunction events that would 

require immediate corrective action and have the potential to 

emit large quantities of HAP. In addition, while the owner or 

operator must follow the PRD recordkeeping and reporting 

requirements for each release to the atmosphere, these tasks can 

be completed after the release has occurred and should not 

interfere with any actions needed to ensure process and system 

safety. Further, we note that the rule does not require PRDs to 

be vented to control devices, as suggested by a commenter; 

however, a facility owner or operator may choose to vent PRDs to 

control devices. We also note that the commenters did not 

provide data or information in support of their speculation that 

venting a PRD to a control device would reduce the effectiveness 

of the PRD or that a safety hazard would be created. 

Regarding the comments that the PRD monitoring requirements 

will dictate the types of systems used at facilities, we note 

that, as discussed elsewhere in this preamble, the requirements 

for PRD monitoring provide a wide latitude in the type of 

monitoring system used, which may be chosen by the facility 
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owner or operator, providing that the basic requirements for the 

system are met. 

Comment: Several commenters state that the EPA added the 

PRD requirements without regard to the CAA section 112 MACT 

development process and without providing the legal 

justification, adequate record basis or technical justification. 

Two of these commenters add that they do not believe that the 

EPA has a legal obligation nor the discretion to promulgate the 

proposed PRD provisions because the PRD monitoring and reporting 

requirements were not derived from the technology reviews, in 

response to any residual risks detected, or the United States 

Court of Appeals for the District of Columbia Circuit’s 

invalidation of the SSM provisions in the 40 CFR part 63 General 

Provisions. Two commenters suggest that these revisions should 

be evaluated as part of the technology review, and the EPA 

should analyze the technical feasibility, potential emissions 

reductions and cost effectiveness of the revisions. 

Several commenters argue that the EPA provided no data to 

support the claim that a large number of releases occur and may 

emit large quantities of HAP, or to support the contention that 

releases are not being identified. One commenter asserts that 

PRD releases are rare, and that the EPA’s data from PRD episodes 

at California South Coast refineries, which resulted in large 

emissions, does not apply to chemical operations. Another 
Page 95 of 180

commenter notes that at its facility, PRD releases are 

infrequent events that last for 1 or 2 seconds and states that 

the proposed PRD provisions are not warranted. One commenter 

states that the industry already quantifies and reports releases 

through the use of pressure monitoring and other types of 

process controls that are also implemented to maintain stable 

operation. The commenter asserts that the EPA is establishing a 

numeric standard of zero that is based on the premise that most 

relief devices do not release, which fails to acknowledge the 

differences between systems.

Response: Under CAA section 112(d)(2), the EPA must 

promulgate technology-based standards that reflect the maximum 

degree of emission reductions of HAP achievable (after 

considering cost, energy requirements, and non-air quality 

health and environmental impacts), and such standards must 

contain compliance assurance provisions to make sure that they 

are practicably enforceable. Nothing in the CAA or its 

legislative history suggests that the EPA is prohibited from 

reviewing and revising MACT standards and their compliance 

assurance provisions, except as part of the CAA section 

112(d)(6) or CAA section 112(f) reviews or an action taken in 

response to a ruling by a Court. The amendments being finalized 

for PRD releases do not impose new emission standards for which 

a MACT analysis is required by the CAA. Instead, they prohibit 
Page 96 of 180

releases to the atmosphere from PRDs in off-site material 

service that are not appropriate for exemption from emission 

standards following the 2008 Sierra Club v. EPA ruling, and 

impose additional monitoring requirements to address potential 

releases.

In light of, and consistent with, the Sierra Club v. EPA

ruling, the EPA is eliminating the SSM exemption in the OSWRO 

MACT standards and requiring that the standards apply at all 

times, including during periods of SSM. In addition, in order 

for our treatment of malfunction-caused pressure releases to the 

atmosphere to conform with the reasoning of the Court’s ruling, 

the final rule adds a provision stating that releases of HAP 

listed in Table 1 of subpart DD directly to the atmosphere from 

PRDs in off-site material service are prohibited. To prohibit 

these malfunction-caused releases, it is not necessary for us to 

set an emission standard that is based on a MACT floor or 

beyond-the-floor analysis; indeed, the EPA has consistently 

explained that we are not required to take malfunctions into 

account in setting standards or to devise standards that apply 

specifically to malfunction-caused emissions, such as PRD 

releases that cause HAP emissions only during malfunctions. The 

final rule requires that sources monitor PRDs using a system 

that is capable of detecting and recording the time and duration 

of each pressure release, and the final rule provides owners and 
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operators flexibility to either install a monitor on the PRD or 

to use equipment and operations they already have in place if 

they are sufficient to detect and indicate pressure releases to 

the atmosphere. The rule also establishes requirements that 

these release indicators be capable of immediately notifying 

operators that a release is occurring, so that HAP emissions 

from these releases can be mitigated as soon as possible.

Additionally, the final rule requires reporting of PRD releases 

to the atmosphere to ensure that these releases will be reported 

nationally.

Contrary to some commenters’ assertions that the EPA did 

not provide data to support the claim that a large number of PRD 

releases occur and may emit large quantities of HAP, a report by 

the South Coast Air Quality Management District (SCAQMD) 

containing such data was referenced and made available with the 

proposed rule in the memorandum, Cost Impacts of Pressure Relief 

Device Monitoring for the Off-site Waste and Recovery Operations 

Source Category, available in the docket for this action. The 

referenced report shows that releases from PRDs occur randomly 

and the emissions can only be approximated, but that large 

quantities of emissions may be released. Based on the SCAQMD 

analysis of refinery PRD reports of PRD releases from nine

facilities in its district, there were eight PRD releases from 

2003 to 2006 that were estimated to release greater than 2,000 
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lbs of emissions to the atmosphere, and eight PRD releases from 

2003 to 2006 that were estimated to release between 500 and 

2,000 lbs of emissions to the atmosphere. The SCAQMD analysis 

focuses on VOC emissions (which would include organic HAP 

emissions) from refineries and marine terminals, and information 

provided by the commenter also suggests the SCAQMD analysis 

results are similar to results from another analysis for PRDs at 

chemical production facilities.10 Additionally, the Texas 

Commission on Environmental Quality Emission Event Reporting 

Database is populated with Emission Event Reports from both the 

refinery and chemical sectors where the reason for the report 

was due to a PRD release. This database also shows that PRD 

releases do occur and that the quantity of emissions varies and

can be large. While there may be differences in PRD systems and 

emissions, we continue to believe the requirements proposed and 

being finalized for the OSWRO NESHAP in this action are 

necessary to address the otherwise unregulated HAP emissions 

releases from PRDs.

 

10 The commenter stated that "DuPont experience is that PRD releases are

rare; DuPont has provided data through ACC to EPA." ACC's comments referred 

to a study submitted with its comments for another rulemaking. We located and 

reviewed this study, available at Docket ID No. EPA-HQ-OAR-2011-0435-0041, in 

which the data provided by DuPont is summarized with other data supplied by 

ACC member companies. Both the data provided by ACC and the SCAQMD showed

just over 1 percent of the PRDs had a release. The data provided by ACC 

showed over 20 percent of PRD releases were over 500 pounds and the SCAQMD 

data showed that approximately 38 percent of the PRD releases were over 500 

pounds.
Page 99 of 180

Comment: Several commenters suggest certain types of PRDs 

should be excluded from the PRD requirements because they have a 

low potential to emit large quantities of HAP. These commenters 

specifically state that PRDs in liquid service should be 

excluded from these requirements. For PRDs with little potential 

for loss to the atmosphere, the commenters suggest that the EPA 

set a reporting threshold value equal to the reportable quantity 

(RQ) values in Emergency Planning and Community Right-To-Know 

Act (EPCRA) and/or Comprehensive Environmental Response, 

Compensation, and Liability Act (CERCLA). One commenter asserts 

that the PRD provisions should exclude PRDs in less than 5-

percent VOHAP service. The commenter also suggests that the 

OSWRO MACT should refer to Table 9 of subpart G (VOHAPs) instead 

of Table 1 of subpart DD, should exclude ethylene glycol from 

Table 1 of subpart DD, or should exclude heavy liquids from the 

definition of a PRD. 

This commenter states that the exclusion for PRDs 

discharged to a drain system that meets the requirements of 40 

CFR 63.689 is not useful, and states that the EPA provides no 

cost justification or assessment of potential emission 

reductions of this alternative requirement. The commenter 

asserts that hard-piping discharge to a closed sewer system is 

neither feasible nor safe in many situations, and suggests that 

the EPA require only that liquids be sent for on-site or off-
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site treatment, which would be consistent with the Chemical 

Manufacturing Area Source standard (40 CFR part 63 subpart 

VVVVVV). This commenter and another commenter state that, to be 

consistent with the HON, PRDs that are routed to a fuel gas 

system should be exempted in 40 CFR 63.691(c)(4).

Response: We generally do not agree with the commenters’ 

suggestions to add an exclusion from the PRD requirements for

PRDs that emit smaller amounts of HAP. Regarding PRDs in liquid 

service, equipment is in liquid service when it contains or 

contacts off-site material that is liquid at operating 

conditions, and for processes that are under pressure, the 

liquid may escape as a gas or vapor when released to the 

atmosphere. For these reasons, we continue to believe PRDs in 

liquid service, as well as those in gas/vapor service, should be 

subject to the PRD requirements. We note that the OSWRO NESHAP 

provides that only PRDs that contain or contact off-site 

material having a total HAP concentration equal to or greater 

than 10 percent by weight and that are intended to operate for 

300 hours or more during a calendar year in off-site material 

service are subject to these requirements (see 40 CFR 

63.680(c)(3)). We also disagree with the suggestion that the 

OSWRO MACT refer to Table 9 of subpart G rather than Table 1 of 

subpart DD for HAPs regulated by the PRD provisions. All of the 

provisions of the OSWRO NESHAP apply to the chemicals listed in 
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Table 1 of subpart DD, and we do not find that an exception 

should be made for PRDs to exclude any chemicals with relatively 

lower volatility from these requirements. 

We disagree with the commenter that the provisions that 

exclude PRDs that are routed to a drain system meeting the 

requirements of 40 CFR 63.689 from the PRD release and 

monitoring requirements is an alternate requirement. This 

provision acknowledges that such equipment would not have 

uncontrolled HAP emission releases directly to the atmosphere, 

and therefore the PRD release management and monitoring 

provisions should not apply, but it does not require that any 

equipment be routed to such a drain system. We also note that 

the chemical manufacturing area source standard does not have 

pressure release management or monitoring requirements, and the 

standards in that rule are not applicable to the OSWRO NESHAP. 

The EPA agrees with commenters’ suggestion to exclude PRDs that 

release to a fuel gas system from the PRD monitoring provisions, 

and we have revised the final rule to reflect this change.

Comment: One commenter requests that the EPA clarify the 

meaning of PRDs in light liquid versus gas/vapor service. The 

commenter notes that most facilities subject to the OSWRO MACT 

operate fixed roof storage tanks that must be operated with a 

void space at the top that consists of vapors from the tank and 

may also include a nitrogen blanket. The commenter asserts that 
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the determination of the service type should be based on the 

contents of the tank (i.e., liquid) and not the location where 

the PRD is installed, which will always be at the top of the 

tank in contact with vapors in the void space. The commenter 

asserts that if these types of tanks are considered to be in 

gas/vapor service, then there can be no PRDs on fixed roof tanks 

that operate in liquid service. 

Response: The OSWRO NESHAP directs facility 

owners/operators to comply with the equipment leak requirements 

of the HON, which contains different requirements for various 

components depending upon the type of fluid (whether gas or 

liquid) that flows through (e.g., contains or contacts) the 

components. The basis for these different requirements is data 

collected from petroleum refineries, which indicate that 

emission rates of equipment leak sources decrease as the vapor 

pressure (volatility) of the process fluid decreases. For the 

HON, three classes of volatility were established based on the 

petroleum refinery data and the potential for emissions through 

equipment leaks; these include gas/vapor service, light-liquid 

service and heavy-liquid service. The proposed OSWRO definition 

stated that “In gas/vapor service means that a piece of 

equipment in off-site material service contains a gas or vapor 

at operating conditions.” To clarify our intent and avoid any 

confusion as to whether PRDs with a flow of gas or vapor through 
Page 103 of 180

the device are “in gas/vapor service,” we are revising the 

definition to state, “In gas/vapor service means that a piece of 

equipment in off-site material service contains or contacts a 

gas or vapor at operating conditions.” With this revision, it 

should be clear that a PRD in off-site material service on the 

roof of a tank containing liquid, but which only contacts 

gas/vapor itself and does not contact liquid, would be in 

gas/vapor service. For consistency, we also are revising the 

definition of “in light liquid service” to include equipment 

that contains or contacts liquid.

Comment: One commenter states that the EPA revised the Tank 

Level 1 control requirements in 40 CFR 63.685(c)(2)(i) and 

(iii)(B) to preclude routine venting of PRD by excluding 40 CFR 

63.902(c)(2) and (3); however, the commenter notes that this 

revision would also preclude the operation of conservation vents 

on Level 1 tanks. The commenter suggests that the EPA remove the 

exclusion or amend the provision to allow for the operation of 

conservation vents. 

Response: We agree that conservation vents should be 

allowed to operate on Level 1 tanks, and, while we do not 

believe these would meet the definition of a PRD, we have 

revised the text of the final rule at 40 CFR 

63.684(c)(2)(iii)(B)(1) to clarify that the use of these devices 

is permitted.
Page 104 of 180

iv. Other Comments

Comment: One commenter states that the EPA should provide 

an exemption in 40 CFR 63.693(b)(9) to the performance testing 

or design evaluation requirements for combustion devices if a 

unit has been issued a final or interim status RCRA permit, 

since performance tests are required to obtain such a permit. 

Response: The EPA agrees with the commenter that the 

combustion units required to obtain a RCRA permit would have 

conducted performance tests under those provisions which satisfy 

the performance test requirements of the OSWRO NESHAP and that 

separate or additional performance testing would not be 

necessary. We have therefore added a provision to the final rule 

that excludes combustion devices that have been issued a RCRA 

permit from the OSWRO NESHAP performance test requirements.

Comment: One commenter states that the OSWRO provisions 

should more clearly indicate that facilities subject to onsite 

wastewater provisions under other CAA MACT regulations should 

not also be required to comply with the OSWRO NESHAP. The 

commenter references the applicability provisions that exclude 

certain types of waste subject to other MACT rules in 40 CFR 

63.680(b)(2)(v), and states that the exclusion is limited to 

SOCMI. The commenter suggests removing paragraphs 40 CFR 

63.680(b)(2)(v)(A) and (B) to broaden the exclusion to 
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wastewater sources subject to any other subpart in 40 CFR part 

63. 

Response: The EPA agrees with the commenter that the 

exclusion of certain types of waste in 40 CFR 63.680(b)(2)(v) 

should not be limited to SOCMI and has revised the regulatory 

text to exempt waste that is transferred from a facility at 

which management of the waste has complied with the air emission 

control standards for process wastewater specified by another 

subpart in 40 CFR part 63.

4. What is the rationale for our final decisions regarding these 

other changes to the OSWRO NESHAP?

For the reasons provided above and in the preamble for the 

proposed rule, we are finalizing the proposed provisions 

regarding electronic reporting; routine maintenance; OELs; 

safety devices, pressure tanks, bypasses and PRDs; performance 

test method clarifications and alternative methods; and other 

clarifications and corrections.

For the reasons provided above, we are making the 

revisions, clarifications and corrections noted in section 

IV.D.2 in the final rule.

V. Summary of Cost, Environmental and Economic Impacts and 

Additional Analyses Conducted

A. What are the affected sources?
Page 106 of 180

We estimate that there are 56 major source OSWRO 

facilities. Based on available permit information, seven 

facilities are known to be exempt from most of the rule 

requirements due to the low HAP content of the off-site waste 

they receive or because they comply instead with 40 CFR part 61, 

subpart FF, as allowed by the OSWRO NESHAP, and they are not 

expected to be affected by the final rule revisions. These 

facilities are only required to document that the total annual 

quantity of the HAP contained in the off-site material received 

at the plant site is less than 1 megagram per year, and they are 

not subject to any other emissions limits or monitoring, 

reporting or recordkeeping requirements. We are not aware of any 

new OSWRO facilities that are expected to be constructed in the 

foreseeable future.

B. What are the air quality impacts?

For equipment leaks, we are eliminating the option of

complying with 40 CFR part 61, subpart V, and requiring 

facilities in the OSWRO source category to comply with 40 CFR 

part 63, subpart H, including connector monitoring. Our revised

estimate of the HAP emission reduction for this change is

approximately 185 tpy. 

For tanks, we are finalizing requirements for tanks of

certain sizes and containing materials above certain vapor 
Page 107 of 180

pressures to use Level 2 controls. Our revised estimate of the 

HAP emission reduction for this change is approximately 26 tpy. 

We do not anticipate any HAP emission reduction from our 

clarification of the rule provision “seal the open end” (in the 

context of OELs), clarification of the scope of the routine 

maintenance provisions, or requirement to electronically report 

the results of emissions testing.

For the revisions to the MACT standards regarding SSM,

including monitoring of PRDs in off-site material service, we 

were not able to quantify the possible emission reductions, so 

none are included in our assessment of air quality impacts.

Therefore, the estimated total HAP emission reductions for 

the final standards for the OSWRO source category are estimated 

to be 211 tpy.

C. What are the cost impacts?

For equipment leaks, we are eliminating the option of

complying with 40 CFR part 61, subpart V, and requiring 

facilities in the OSWRO source category to comply with 40 CFR 

part 63, subpart H (including connector monitoring). We estimate 

the nationwide capital costs to be $2.1 million and the 

annualized costs to be $664,000.

For tanks, we are requiring tanks of certain sizes and

containing materials above certain vapor pressures to use Level 
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2 controls. We estimate the nationwide capital costs to be 

$139,000 and the annualized costs to be $192,000.

We do not anticipate any quantifiable capital or annualized 

costs for our definition of “seal” (in the context of OELs), 

clarification of the scope of the routine maintenance provisions 

and requirement to electronically report the results of 

emissions testing.

For the requirement to install and operate monitors on 

PRDs, we estimate the nationwide capital costs to be $1.9

million and the annualized costs to be $270,000. Therefore, the 

total capital costs for the final amendments for the OSWRO 

source category are approximately $4.1 million and the total 

annualized costs are approximately $1.1 million.

D. What are the economic impacts?

Both the magnitude of control costs needed to comply with a 

regulation and the distribution of these costs among affected 

facilities can have a role in determining how the market will 

change in response to that regulation. Total annualized costs 

for the final amendments are estimated to be about $1.1 million. 

The average annualized cost per facility is estimated to be 

about $23,000. Without detailed industry data, it is not 

possible to conduct a complete quantitative analysis of economic

impacts. However, prior analyses suggest the impacts of these 

final amendments will be minimal. The Economic Impact Analysis 
Page 109 of 180

for the final OSWRO NESHAP11 found that demand for off-site waste 

services was highly inelastic. This means that suppliers are

predominantly able to pass along cost increases to consumers 

through higher prices with little, if any, decrease in the

quantity of service demanded. While we do not have specific 

information on prices charged or the quantity of services

provided, company revenues are a function of both these factors. 

The cost-to-sales ratio is less than 1 quarter of 1 percent for 

all of the 27 firms included in this analysis, suggesting any

increase in price will be minimal.

E. What are the benefits?

We have estimated that this action will achieve HAP 

emissions reduction of 211 tpy. The final standards will result 

in significant reductions in the actual and MACT-allowable 

emissions of HAP and will reduce the actual and potential cancer 

risks and non-cancer health effects due to emissions of HAP from 

this source category, as discussed in the proposal preamble (79 

FR 37869-37870). We have not quantified the monetary benefits 

associated with these reductions; however, these avoided

emissions will result in improvements in air quality and reduced 

 

11 EPA. June 1996.
Page 110 of 180

negative health effects associate with exposure to air pollution 

of these emissions.

F. What analysis of environmental justice did we conduct?

The EPA is making environmental justice part of its mission 

by identifying and addressing, as appropriate, 

disproportionately high and adverse human health or 

environmental effects of its programs, policies and activities 

on minority populations and low-income populations in the United 

States. The EPA has established policies regarding the 

integration of environmental justice into the agency’s 

rulemaking efforts, including recommendations for the 

consideration and conduct of analyses to evaluate potential 

environmental justice concerns during the development of a rule. 

Following these recommendations, to gain a better 

understanding of the source category and near source 

populations, the EPA conducted a proximity analysis for OSWRO 

facilities prior to proposal to identify any overrepresentation 

of minority, low income or indigenous populations. This analysis 

gives an indication of the prevalence of sub-populations that 

may be exposed to air pollution from the sources. We have 

revised this analysis to include four additional OSWRO 

facilities that the EPA learned about after proposal.

The EPA has determined that this final rule will not have 

disproportionately high and adverse human health or 
Page 111 of 180

environmental effects on minority, low income or indigenous 

populations. Additionally, the final changes to the NESHAP 

increase the level of environmental protection for all affected 

populations by reducing emissions from equipment leaks and tanks

and do not cause any disproportionately high and adverse human 

health or environmental effects on any population, including any 

minority, low income or indigenous populations.

Further details concerning this analysis are presented in the 

memorandum titled, Updated Environmental Justice Review: OffSite Waste and Recovery Operations RTR, a copy of which is 

available in the docket for this action.

G. What analysis of children’s environmental health did we

conduct?

As part of the health and risk assessments, as well as the 

proximity analysis conducted for this action, risks to infants 

and children were assessed. These analyses are documented in the 

Residual Risk Assessment for the Off-Site Waste and Recovery 

Operations Source Category in Support of the February 2015 Risk 

and Technology Review Final Rule and the Updated Environmental 

Justice Review: Off-Site Waste and Recovery Operations RTR

documents and are available in the docket for this action.

The results of the proximity analysis show that the average 

percentage of children 17 years and younger in close proximity 

to OSWRO is similar to the percentage of the national population 
Page 112 of 180

in this age group. The difference in the absolute number of 

percentage points of the population 17 years old and younger 

from the national average indicates a 7-percent overrepresentation near OSWRO facilities. Consistent with the EPA’s 

Policy on Evaluating Health Risks to Children, we conducted 

inhalation and multipathway risk assessments for the OSWRO 

source category considering risk to infants and 

children.

12 Children are exposed to chemicals emitted to the 

atmosphere via two primary routes: either directly via 

inhalation, or indirectly via ingestion or dermal contact with 

various media that have been contaminated with the emitted 

chemicals. The EPA considers the possibility that children might 

be more sensitive than adults to toxic chemicals, including 

chemical carcinogens. 

For our inhalation risk assessment, several carcinogens 

emitted by facilities in this source category have a mutagenic 

mode of action. For these compounds, we applied the agedependent adjustment factors (ADAF) described in the EPA’s 

Supplemental Guidance for Assessing Susceptibility from Early-

 

12 Policy on Evaluating Health Risks to Children, U.S. Environmental 

Protection Agency, Washington, DC. May 2014. Available at 

http://www2.epa.gov/sites/production/files/2014-

05/documents/1995_childrens_health_policy_statement.pdf.
Page 113 of 180

Life Exposure to Carcinogens.13 This adjustment has the effect of 

increasing the estimated lifetime risks for these pollutants by 

a factor of 1.6. For one group of these chemicals with a 

mutagenic mode of action, POM, only a small fraction of the 

total emissions were reported as individual compounds. The EPA 

expresses carcinogenic potency of POM relative to the 

carcinogenic potency of benzo[a]pyrene, based on evidence that 

carcinogenic POM have the same mutagenic mode of action as does 

benzo[a]pyrene. The EPA’s Science Policy Council recommends 

applying the ADAF to all carcinogenic compounds for which risk 

estimates are based on potency relative to benzo[a]pyrene. 

Accordingly, we have applied the ADAF to the benzo[a]pyreneequivalent mass portion of all POM mixtures. 

For our multipathway screening assessment (i.e., 

ingestion), we assessed risks for adults and various age groups 

of children. Childrens’ exposures are expected to differ from 

exposures of adults due to differences in body weights, 

ingestion rates, dietary preferences and other factors. It is 

important, therefore, to evaluate the contribution of exposures 

during childhood to total lifetime risk using appropriate 

 

13 Supplemental Guidance for Assessing Susceptibility from Early-Life Exposure 

to Carcinogens. Risk Assessment Forum, U.S. Environmental Protection Agency, 

Washington, DC. EPA/630/R–03/003F. March 2005. Available at 

http://www.epa.gov/raf/publications/pdfs/childrens_supplement_final.pdf.
Page 114 of 180

exposure factor values, applying ADAF as appropriate. The EPA 

developed a health protective exposure scenario whereby the 

receptor, at various lifestages, receives ingestion exposure via 

both the farm food chain and the fish ingestion pathways. The 

analysis revealed that fish ingestion is the dominant exposure 

pathway across all age groups for several pollutants, including 

POM. For POM, the farm-food-chain also is a major route of 

exposure, with beef and dairy contributing significantly to the 

lifetime average daily dose. Preliminary calculations of 

estimated dermal exposure and risk from these pollutants showed 

that the dermal exposure route is not a significant risk pathway 

relative to ingestion exposures.

Based on the analyses described above, the EPA has 

determined that the changes to this rule, which will reduce 

emissions of HAP by over 200 tpy, will lead to reduced risk to 

children and infants.

VI. Statutory and Executive Order Reviews

Additional information about these statutes and Executive 

Orders can be found at http://www2.epa.gov/lawsregulations/laws-and-executive-orders.

A. Executive Order 12866: Regulatory Planning and Review and 

Executive Order 13563: Improving Regulation and Regulatory 

Review
Page 115 of 180

This action is not a significant regulatory action and was,

therefore, not submitted to the Office of Management and Budget 

(OMB) for review.

B. Paperwork Reduction Act (PRA)

The information collection activities in this rule have 

been submitted for approval to the OMB under the PRA. The 

Information Collection Request (ICR) document that the EPA 

prepared has been assigned EPA ICR number 1717.11. You can find 

a copy of the ICR in the docket for this rule, and it is briefly 

summarized here. The information collection requirements are not 

enforceable until OMB approves them.

The information requirements in this rulemaking are based 

on the notification, recordkeeping and reporting requirements in 

the NESHAP General Provisions (40 CFR part 63, subpart A), which 

are mandatory for all operators subject to national emission 

standards. These notifications, reports and records are 

essential in determining compliance, and are specifically 

authorized by CAA section 114 (42 U.S.C. 7414). All information 

submitted to the EPA pursuant to the recordkeeping and reporting 

requirements for which a claim of confidentiality is made is 

safeguarded according to agency policies set forth in 40 CFR 

part 2, subpart B.
Page 116 of 180

Respondents/affected entities: OSWRO facilities that store, 

treat, recycle, reprocess, or dispose of wastes containing 

organic chemical compounds. 

Respondent’s obligation to respond: mandatory (42 U.S.C. 7414)

Estimated number of respondents: 49

Frequency of response: semiannual

Total estimated burden: 49,118 hours (per year). Burden is 

defined at 5 CFR 1320.3(b).

Total estimated cost: $4.1 million (per year), includes $1.2 

million annualized capital or operation & maintenance costs. 

An agency may not conduct or sponsor, and a person is not 

required to respond to, a collection of information unless it 

displays a currently valid OMB control number. The OMB control 

numbers for the EPA’s regulations in 40 CFR are listed in 40 CFR 

part 9. When OMB approves this ICR, the agency will announce 

that approval in the Federal Register and publish a technical 

amendment to 40 CFR part 9 to display the OMB control number for 

the approved information collection activities contained in this 

final rule.

C. Regulatory Flexibility Act (RFA)

I certify that this action will not have a significant 

economic impact on a substantial number of small entities under 

the RFA. The small entities subject to the requirements of this 

action are businesses that can be classified as small firms 
Page 117 of 180

using the SBA size standards for their respective industries.

The agency has determined that of the 27 firms that own the 49

facilities in the OSWRO source category, four firms, or 15 

percent, can be classified as small firms. Based on the sales 

test screening methodology, all four firms will experience 

minimal impact, or a cost-to-sales ratio of 1 percent or less. 

Details of this analysis are presented in the memo, Economic 

Impact Analysis for Risk and Technology Review: Off-site Waste 

and Recovery Operations Source Category, which is available in 

the docket for this action.

D. Unfunded Mandates Reform Act (UMRA)

This action does not contain an unfunded mandate of $100 

million or more as described in UMRA, 2 U.S.C. 1531–1538, and 

does not significantly or uniquely affect small governments. The 

action imposes no enforceable duty on any state, local or tribal 

governments, or on the private sector.

E. Executive Order 13132: Federalism

This action does not have federalism implications. It will 

not have substantial direct effects on the states, on the 

relationship between the national government and the states, or 

on the distribution of power and responsibilities among the 

various levels of government.

F. Executive Order 13175: Consultation and Coordination with 

Indian Tribal Governments
Page 118 of 180

This action does not have tribal implications as specified 

in Executive Order 13175. There are no OSWRO facilities that are 

owned or operated by tribal governments. Thus, Executive Order 

13175 does not apply to this action. 

G. Executive Order 13045: Protection of Children from 

Environmental Health Risks and Safety Risks

This action is not subject to Executive Order 13045 because 

it is not economically significant as defined in Executive Order 

12866, and because the EPA does not believe the environmental 

health or safety risks addressed by this action present a 

disproportionate risk to children. This action’s health and risk 

assessments are contained in the: Residual Risk Assessment for 

the Off-Site Waste and Recovery Operations Source Category in 

Support of the February 2015 Risk and Technology Review Final 

Rule document, which is available in the docket for this action, 

and are discussed in section V.G of this preamble.

H. Executive Order 13211: Actions Concerning Regulations That 

Significantly Affect Energy Supply, Distribution or Use

This action is not subject to Executive Order 13211 because 

it is not a significant regulatory action under Executive Order 

12866.

I. National Technology Transfer and Advancement Act (NTTAA)

This action involves technical standards. The EPA has 

decided to add EPA Methods 2F and 2G to the list of methods 
Page 119 of 180

allowed to determine process vent stream gas volumetric flow 

rate. No applicable voluntary consensus standards (VCS) were 

identified for these methods. In addition, the EPA is finalizing 

provisions to allow EPA Method 3A as an alternative to EPA 

Method 3B for determining the oxygen concentration to use in 

oxygen correction equations. While the EPA identified several 

candidate VCS for this method (ANSI/ASME PTC 19-10-1981 Part 10, 

ASME B133.9-1994 (2001), ISO 10396:1993 (2007), ISO 12039:2001, 

ASTM D5835-95 (2013), ASTM D6522-00 (2011), and CAN/CSA Z223.2-

M86 (1999)) as being potentially applicable, the agency decided 

not to use them. The use of these VCS would not be practical due 

to lack of equivalency, documentation, validation data and other 

important technical and policy considerations. The EPA also is 

finalizing requirements to use EPA Method 25A to determine 

compliance with the control device percent reduction 

requirement, if the owner or operator chooses to measure total 

organic content. While the EPA identified two candidate VCS (ISO 

14965:2000(E), EN 12619 (1999)) as being potentially applicable, 

we are not including either standard in this final rule. The use 

of these VCS would not be practical due to the limited 

measurement ranges of these methods. (For more detail, see the 

document titled, Voluntary Consensus Standard Results for 

NESHAP: Off-Site Waste and Recovery Operations 40 CFR Part 63, 

Subpart DD in the docket for this final rule.) The EPA solicited 
Page 120 of 180

comments on VCS and invited the public to identify potentiallyapplicable VCS, but no comments were received regarding this 

aspect of the rule.

J. Executive Order 12898: Federal Actions to Address 

Environmental Justice in Minority Populations and Low-Income 

Populations

The EPA believes the human health or environmental risk 

addressed by this action will not have potential 

disproportionately high and adverse human health or 

environmental effects on minority, low-income or indigenous 

populations because it increases the level of protection 

provided to human health or the environment. The results of this 

evaluation are contained in the memorandum titled, Updated 

Environmental Justice Review: Off-Site Waste and Recovery 

Operations RTR, which is available in the docket for this 

action, and are discussed in section V.F of this preamble.

K. Congressional Review Act (CRA)

This action is subject to the CRA, and the EPA will submit 

a rule report to each House of the Congress and to the 

Comptroller General of the United States. This action is not a 

“major rule” as defined by 5 U.S.C. 804(2).
Page 121 of 180

List of Subjects in 40 CFR Part 63 

Environmental protection, Administrative practice and 

procedures, Air pollution control, Hazardous substances, 

Intergovernmental relations, Reporting and recordkeeping 

requirements.

Dated:

____________________________.

____________________________

Gina McCarthy,

Administrator.
Page 122 of 180

For the reasons stated in the preamble, the Environmental 

Protection Agency (EPA) is amending title 40, chapter I, of the 

Code of Federal Regulations (CFR) as follows:

PART 63— NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR 

POLLUTANTS FOR SOURCE CATEGORIES

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

follows:

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

Subpart DD— NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR 

POLLUTANTS FROM OFF-SITE WASTE AND RECOVERY OPERATIONS

2. Section 63.680 is amended by:

a. Revising paragraphs (b)(2)(v) introductory text, (e)(1) 

and (2); and

b. Adding paragraph (g) to read as follows:

§ 63.680 Applicability and designation of affected sources.

* * * * *

(b) * * *

(2) * * *

(v) Waste that is transferred from a chemical manufacturing 

plant or other facility for which the owner or operator of the 

facility from which the waste is transferred has complied with 

the provisions of the air emission control standards for process 

wastewater specified by another 40 CFR part 63 subpart. This 

exemption does not apply to a source which complies with another 
Page 123 of 180

40 CFR part 63 subpart by transferring its wastewater off-site 

for control.

* * * * *

(e) * * *

(1) Existing sources. The owner or operator of an affected 

source that commenced construction or reconstruction before 

October 13, 1994, must achieve compliance with the provisions of 

this subpart on or before the date specified in paragraph 

(e)(1)(i), (ii), or (iii) of this section as applicable to the 

affected source.

(i) For an affected source that commenced construction or 

reconstruction before October 13, 1994 and receives off-site 

material for the first time before February 1, 2000, the owner 

or operator of this affected source must achieve compliance with 

the provisions of the subpart (except §§ 63.685(b)(1)(ii), 

63.691(b)(2), and 63.691(c)(3)(i) and (ii) of this subpart) on

or before February 1, 2000 unless an extension has been granted 

by the Administrator as provided in 40 CFR 63.6(i). These 

existing affected sources shall be in compliance with the tank 

requirements of § 63.685(b)(1)(ii) of this subpart 2 years after 

the publication date of the final amendments on [insert date of 

publication in the Federal Register], the equipment leak 

requirements of § 63.691(b)(2) of this subpart 1 year after the 

publication date of the final amendments on [insert date of 
Page 124 of 180

publication in the Federal Register], and the pressure relief 

device monitoring requirements of § 63.691(c)(3)(i) and (ii) of 

this subpart 3 years after the publication date of the final 

amendments on [insert date of publication in the Federal 

Register].

(ii) For an affected source that commenced construction or 

reconstruction before October 13, 1994, but receives off-site 

material for the first time on or after February 1, 2000, but 

before [insert date of publication in the Federal Register], the 

owner or operator of the affected source must achieve compliance 

with the provisions of this subpart (except §§ 63.685(b)(1)(ii), 

63.691(b)(2), and 63.691(c)(3)(i) and (ii) of this subpart) upon 

the first date that the affected source begins to manage offsite material. These existing affected sources shall be in 

compliance with the tank requirements of § 63.685(b)(1)(ii) of 

this subpart 2 years after the publication date of the final 

amendments on [insert date of publication in the Federal 

Register], the equipment leak requirements of § 63.691(b)(2) of 

this subpart 1 year after the publication date of the final 

amendments on [insert date of publication in the Federal 

Register], and the pressure relief device monitoring 

requirements of § 63.691(c)(3)(i) and (ii) of this subpart 3

years after the publication date of the final amendments on 

[insert date of publication in the Federal Register].
Page 125 of 180

(iii) For an affected source that commenced construction or 

reconstruction before October 13, 1994, but receives off-site 

material for the first time on or after [insert date of 

publication in the Federal Register], the owner or operator of 

the affected source must achieve compliance with the provisions 

of this subpart (except §§ 63.685 (b)(1)(ii), 63.691(b)(2), and 

63.691(c)(3)(i) and (ii) of this subpart) upon the first date 

that the affected source begins to manage off-site material. 

These existing affected sources shall be in compliance with the 

tank requirements of § 63.685(b)(1)(ii) of this subpart 2 years 

after the publication date of the final amendments on [insert 

date of publication in the Federal Register], the equipment leak 

requirements of § 63.691(b)(2) of this subpart 1 year after the 

publication date of the final amendments on [insert date of 

publication in the Federal Register], and the pressure relief 

device monitoring requirements of § 63.691(c)(3)(i) and (ii) of 

this subpart 3 years after the publication date of the final 

amendments on [insert date of publication in the Federal 

Register].

(2) New sources. The owner or operator of an affected 

source for which construction or reconstruction commences on or 

after October 13, 1994, must achieve compliance with the 

provisions of this subpart (except §§ 63.685(b)(2), 

63.691(b)(2), and 63.691(c)(3)(i) and (ii) of this subpart) on 
Page 126 of 180

or before July 1, 1996, or upon initial startup of operations, 

whichever date is later as provided in 40 CFR 63.6(b). New 

affected sources that commenced construction or reconstruction 

after October 13, 1994, but on or before July 2, 2014, shall be 

in compliance with the tank requirements of § 63.685(b)(2) of 

this subpart 2 years after the publication date of the final 

amendments, the equipment leak requirements of § 63.691(b)(2) of 

this subpart 1 year after the publication date of the final 

amendments, and the pressure relief device monitoring 

requirements of § 63.691(c)(3)(i) and (ii) of this subpart 3

years after the effective date of the final amendments. New 

affected sources that commence construction or reconstruction 

after July 2, 2014, shall be in compliance with the tank 

requirements of § 63.685(b)(2) of this subpart, the equipment 

leak requirements of § 63.691(b)(2) of this subpart, and the 

pressure relief device monitoring requirements of 

§ 63.691(c)(3)(i) and (ii) of this subpart upon initial startup

or by the effective date of the final amendments, whichever is 

later.

* * * * *

(g) Applicability of this subpart. (1) The emission 

limitations set forth in this subpart and the emission 

limitations referred to in this subpart shall apply at all times 

except during periods of non-operation of the affected source 
Page 127 of 180

(or specific portion thereof) resulting in cessation of the 

emissions to which this subpart applies.

(2) The owner or operator shall not shut down items of 

equipment that are required or utilized for compliance with this 

subpart during times when emissions are being routed to such 

items of equipment, if the shutdown would contravene 

requirements of this subpart applicable to such items of 

equipment.

3. Section 63.681 is amended by:

a. Adding, in alphabetical order, definitions for “Bypass”, 

“In gas/vapor service”, “In heavy liquid service”, “In light 

liquid service”, “In liquid service”, “Pressure release”, and 

“Pressure relief device or valve”; 

b. Revising the definitions of “Point-of-treatment” and 

“Process vent”; and

c. Removing the definition of “Safety device” to read as 

follows:

§ 63.681 Definitions.

* * * * *

Bypass means diverting a process vent or closed vent system 

stream to the atmosphere such that it does not first pass 

through an emission control device.

* * * * *
Page 128 of 180

In gas/vapor service means that a piece of equipment in off-site 

material service contains or contacts a gas or vapor at 

operating conditions.

In heavy liquid service means that a piece of equipment in offsite material service is not in gas/vapor service or in light 

liquid service.

In light liquid service means that a piece of equipment in offsite material service contains or contacts a liquid that meets 

the following conditions:

(1) The vapor pressure of one or more of the organic 

compounds is greater than 0.3 kilopascals at 20°C,

(2) The total concentration of the pure organic compounds 

constituents having a vapor pressure greater than 0.3 

kilopascals at 20°C is equal to or greater than 20 percent by 

weight of the total process stream, and

(3) The fluid is a liquid at operating conditions.

Note: Vapor pressures may be determined by the methods described 

in 40 CFR 60.485(e)(1).

In liquid service means that a piece of equipment in off-site 

material service is not in gas/vapor service.

* * * * *

Point-of-treatment means a point after the treated material 

exits the treatment process but before the first point 

downstream of the treatment process exit where the organic 
Page 129 of 180

constituents in the treated material have the potential to 

volatilize and be released to the atmosphere. For the purpose of 

applying this definition to this subpart, the first point

downstream of the treatment process exit is not a fugitive 

emission point due to an equipment leak from any of the 

following equipment components: Pumps, compressors, valves, 

connectors, instrumentation systems, or pressure relief devices.

Pressure release means the emission of materials resulting from 

the system pressure being greater than the set pressure of the 

pressure relief device. This release can be one release or a 

series of releases over a short time period.

Pressure relief device or valve means a safety device used to 

prevent operating pressures from exceeding the maximum allowable 

working pressure of the process equipment. A common pressure 

relief device is a spring-loaded pressure relief valve. Devices 

that are actuated either by a pressure of less than or equal to 

2.5 pounds per square inch gauge or by a vacuum are not pressure 

relief devices.

* * * * *

Process vent means an open-ended pipe, stack, or duct through 

which a gas stream containing HAP is continuously or 

intermittently discharged to the atmosphere from any of the 

processes listed in § 63.680(c)(2)(i) through (vi) of this 

subpart. For the purpose of this subpart, a process vent is none 
Page 130 of 180

of the following: a pressure relief device; an open-ended line 

or other vent that is subject to the equipment leak control 

requirements under § 63.691 of this subpart; or a stack or other 

vent that is used to exhaust combustion products from a boiler, 

furnace, process heater, incinerator, or other combustion 

device.

* * * * *

4. Section 63.683 is amended by:

a. Revising the first sentence of paragraph (c)(1)(ii); and 

b. Adding paragraphs (e) and (f) to read as follows:

§ 63.683 Standards: General.

* * * * *

(c) * * *

(1) * * *

(ii) The owner or operator determines before placing offsite material in the process equipment associated with the 

process vent that the average VOHAP concentration of the offsite material is less than 500 ppmw at the point-of-delivery. * 

* *

* * * * *

(e) General Duty. At all times, the owner or operator must 

operate and maintain any affected source, including associated 

air pollution control equipment and monitoring equipment, in a 

manner consistent with safety and good air pollution control 
Page 131 of 180

practices for minimizing emissions. The general duty to minimize 

emissions does not require the owner operator to make any 

further efforts to reduce emissions if levels required by the 

applicable standard have been achieved. Determination of whether 

a source is operating in compliance with operation and 

maintenance requirements will be based on information available 

to the Administrator, which may include, but is not limited to, 

monitoring results, review of operation and maintenance 

procedures, review of operation and maintenance records, and 

inspection of the source.

(f) In addition to the cases listed in § 63.695(e)(4) of 

this subpart, deviation means any of the cases listed in 

paragraphs (f)(1) through (6) of this section. 

(1) Any instance in which an affected source subject to 

this subpart, or an owner or operator of such a source, fails to 

meet any requirement or obligation established by this subpart, 

including, but not limited to, any emission limit, operating 

limit or work practice standard.

(2) When a performance test indicates that emissions of a 

pollutant in Table 1 to this subpart are exceeding the emission 

standard for the pollutant specified in Table 1 to this subpart.

(3) When the average value of a monitored operating 

parameter, based on the data averaging period for compliance 
Page 132 of 180

specified in § 63.695 of this subpart, does not meet the 

operating limit specified in § 63.693 of this subpart.

(4) When an affected source discharges directly into the 

atmosphere from any of the sources specified in paragraphs 

(f)(4)(i) and (ii) of this section.

(i) A pressure relief device, as defined in § 63.681 of 

this subpart.

(ii) A bypass, as defined in § 63.681 of this subpart.

(5) Any instance in which the affected source subject to 

this subpart, or an owner or operator of such a source, fails to 

meet any term or condition specified in paragraph (f)(5)(i) or 

(ii) of this section.

(i) Any term or condition that is adopted to implement an 

applicable requirement in this subpart.

(ii) Any term or condition relating to compliance with this 

subpart that is included in the operating permit for an affected 

source to obtain such a permit.

(6) Any failure to collect required data, except for 

periods of monitoring system malfunctions, repairs associated 

with monitoring system malfunctions, and required monitoring 

system quality assurance or quality control activities 

(including, as applicable, calibration checks and required zero 

and span adjustments).

5. Section 63.684 is amended by:
Page 133 of 180

a. Revising paragraph (b)(5) introductory text; 

b. Adding paragraph (b)(5)(v); and 

c. Revising paragraph (h) to read as follows:

§ 63.684 Standards: Off-site Material Treatment.

* * * * *

(b) * * *

(5) Incineration. The treatment process must destroy the 

HAP contained in the off-site material stream using one of the 

combustion devices specified in paragraphs (b)(5)(i) through (v) 

of this section.

* * * * *

(v) An incinerator, boiler, or industrial furnace for which 

the owner or operator has submitted a Notification of Compliance 

under 40 CFR 63.1207(j) and 63.1210(d) and complies with the

requirements of 40 CFR part 63, subpart EEE at all times 

(including times when non-hazardous waste is being burned).

* * * * *

(h) The Administrator may at any time conduct or require 

that the owner or operator conduct testing necessary to 

demonstrate that a treatment process is achieving the applicable 

performance requirements of this section. The testing shall be 

conducted in accordance with the applicable requirements of this 

section. The Administrator may elect to have an authorized 
Page 134 of 180

representative observe testing conducted by the owner or 

operator. 

6. Section 63.685 is amended by:

a. Revising paragraphs (b) introductory text, (b)(1), and 

(2);

b. Removing paragraph (b)(4);

c. Revising paragraphs (c)(1), (c)(2)(i) and (iii)(B), 

(g)(2), (h)(3), (i) introductory text; and

d. Removing paragraph (i)(3) and redesignating paragraph 

(i)(4) as paragraph (i)(3) to read as follows:

§ 63.685 Standards: Tanks.

* * * * *

(b) According to the date an affected source commenced 

construction or reconstruction and the date an affected source 

receives off-site material for the first time as established in 

§ 63.680(e)(i) through (iii) of this subpart, the owner or 

operator shall control air emissions from each tank subject to 

this section in accordance with either paragraph (b)(1)(i) or 

(ii) of this section.

(1)(i) For a tank that is part of an existing affected 

source but the tank is not used for a waste stabilization 

process as defined in § 63.681 of this subpart, the owner or 

operator shall determine whether the tank is required to use 

either Tank Level 1 controls or Tank Level 2 controls as 
Page 135 of 180

specified for the tank by Table 3 of this subpart based on the 

off-site material maximum HAP vapor pressure and the tank's 

design capacity. The owner or operator shall control air 

emissions from a tank required by Table 3 to use Tank Level 1 

controls in accordance with the requirements of paragraph (c) of 

this section. The owner or operator shall control air emissions 

from a tank required by Table 3 to use Tank Level 2 controls in 

accordance with the requirements of paragraph (d) of this 

section.

(ii) For a tank that is part of an existing affected source 

but the tank is not used for a waste stabilization process as

defined in § 63.681 of this subpart, the owner or operator shall 

determine whether the tank is required to use either Tank Level 

1 controls or Tank Level 2 controls as specified for the tank by 

Table 4 of this subpart based on the off-site material maximum 

HAP vapor pressure and the tank's design capacity. The owner or 

operator shall control air emissions from a tank required by 

Table 4 to use Tank Level 1 controls in accordance with the 

requirements of paragraph (c) of this section. The owner or 

operator shall control air emissions from a tank required by 

Table 4 to use Tank Level 2 controls in accordance with the 

requirements of paragraph (d) of this section.

(2) For a tank that is part of a new affected source but 

the tank is not used for a waste stabilization process as 
Page 136 of 180

defined in § 63.681 of this subpart, the owner or operator shall 

determine whether the tank is required to use either Tank Level 

1 controls or Tank Level 2 controls as specified for the tank by 

Table 5 of this subpart based on the off-site material maximum 

HAP vapor pressure and the tank's design capacity. The owner or 

operator shall control air emissions from a tank required by 

Table 5 to use Tank Level 1 controls in accordance with the 

requirements of paragraph (c) of this section. The owner or 

operator shall control air emissions from a tank required by 

Table 5 to use Tank Level 2 controls in accordance with the 

requirements of paragraph (d) of this section.

* * * * *

(c) * * *

(1) The owner or operator shall determine the maximum HAP 

vapor pressure for an off-site material to be managed in the 

tank using Tank Level 1 controls before the first time the offsite material is placed in the tank. The maximum HAP vapor 

pressure shall be determined using the procedures specified in 

§ 63.694(j) of this subpart. Thereafter, the owner or operator 

shall perform a new determination whenever changes to the offsite material managed in the tank could potentially cause the 

maximum HAP vapor pressure to increase to a level that is equal 

to or greater than the maximum HAP vapor pressure limit for the 
Page 137 of 180

tank design capacity category specified in Table 3, Table 4, or 

Table 5 of this subpart, as applicable to the tank. 

(2) * * *

(i) The owner or operator controls air emissions from the 

tank in accordance with the provisions specified in subpart OO 

of 40 CFR part 63—National Emission Standards for Tanks—Level 1, 

except that 40 CFR 63.902(c)(2) and (3) shall not apply for the 

purposes of this subpart.

* * * * *

(iii) * * * 

(B) At all other times, air emissions from the tank must be 

controlled in accordance with the provisions specified in 40 CFR 

part 63, subpart OO—National Emission Standards for Tanks—Level 

1, with the exceptions specified in paragraphs (c)(2)(iii)(B)(1) 

and (2) of this section.

(1) Where 40 CFR 63.902(c)(2) provides an exception for a 

spring-loaded pressure-vacuum relief valve, conservation vent, 

or similar type of pressure relief device which vents to the 

atmosphere, only a conservation vent shall be eligible for the 

exception for the purposes of this subpart. 

(2) 40 CFR 63.902(c)(3) shall not apply for the purposes of 

this subpart.

* * * * *

(g) * * *
Page 138 of 180

(2) Whenever an off-site material is in the tank, the fixed 

roof shall be installed with each closure device secured in the 

closed position and the vapor headspace underneath the fixed 

roof vented to the control device except that venting to the 

control device is not required, and opening of closure devices 

or removal of the fixed roof is allowed at the following times: 

(i) To provide access to the tank for performing routine 

inspection, maintenance, or other activities needed for normal 

operations. Examples of such activities include those times when 

a worker needs to open a port to sample liquid in the tank, or 

when a worker needs to open a hatch to maintain or repair 

equipment. Following completion of the activity, the owner or 

operator shall promptly secure the closure device in the closed 

position or reinstall the cover, as applicable, to the tank. 

(ii) To remove accumulated sludge or other residues from 

the bottom of the tank.

* * * * *

(h) * * *

(3) Whenever an off-site material is in the tank, the tank 

shall be operated as a closed system that does not vent to the 

atmosphere except at those times when purging of inerts from the 

tank is required and the purge stream is routed to a closed-vent 

system and control device designed and operated in accordance 

with the requirements of § 63.693 of this subpart. 
Page 139 of 180

(i) The owner or operator who elects to control air 

emissions by using an enclosure vented through a closed-vent 

system to an enclosed combustion control device shall meet the 

requirements specified in paragraphs (i)(1) through (3) of this 

section.

* * * * *

(3) The owner or operator shall inspect and monitor the 

closed-vent system and control device as specified in § 63.693.

7. Section 63.686 is amended by revising paragraphs (b)(1) 

through (3) to read as follows:

§ 63.686 Standards: Oil-water and organic water separators.

* * * * *

(b) * * *

(1) A floating roof in accordance with all applicable 

provisions specified in 40 CFR part 63, subpart VV—National 

Emission Standards for Oil-Water Separators and Organic-Water 

Separators, except that §§ 63.1043(c)(2), 63.1044(c)(2), and 

63.1045(b)(3)(i) shall not apply for the purposes of this 

subpart. For portions of the separator where it is infeasible to 

install and operate a floating roof, such as over a weir 

mechanism, the owner or operator shall comply with the 

requirements specified in paragraph (b)(2) of this section. 

(2) A fixed-roof that is vented through a closed-vent 

system to a control device in accordance with all applicable 
Page 140 of 180

provisions specified in 40 CFR part 63, subpart VV—National 

Emission Standards for Oil-Water Separators and Organic-Water 

Separators, except that §§ 63.1043(c)(2), 63.1044(c)(2), and 

63.1045(b)(3)(i) shall not apply for the purposes of this 

subpart. 

(3) A pressurized separator that operates as a closed 

system in accordance with all applicable provisions specified in 

40 CFR part 63, subpart VV—National Emission Standards for OilWater Separators and Organic-Water Separators, except that 

§§ 63.1043(c)(2), 63.1044(c)(2), and 63.1045(b)(3)(i) shall not 

apply for the purposes of this subpart.

8. Section 63.687 is amended by revising paragraphs (b)(1) 

and (2) to read as follows:

§ 63.687 Standards: Surface impoundments.

* * * * *

(b) * * *

(1) A floating membrane cover in accordance with the 

applicable provisions specified in 40 CFR part 63, subpart QQ—

National Emission Standards for Surface Impoundments, except 

that §§ 63.942(c)(2) and (3) and 63.943(c)(2) shall not apply 

for the purposes of this subpart; or 

(2) A cover that is vented through a closed-vent system to 

a control device in accordance with all applicable provisions 

specified in 40 CFR part 63, subpart QQ—National Emission 
Page 141 of 180

Standards for Surface Impoundments, except that §§ 63.942(c)(2) 

and (3) and 63.943(c)(2) shall not apply for the purposes of 

this subpart. 

9. Section 63.688 is amended by revising paragraphs 

(b)(1)(i), (ii), and (3)(i) to read as follows:

§ 63.688 Standards: Containers.

* * * * *

(b) * * *

(1) * * *

(i) The owner or operator controls air emissions from the 

container in accordance with the standards for Container Level 1 

controls as specified in 40 CFR part 63, subpart PP—National 

Emission Standards for Containers, except that §§ 63.922(d)(4) 

and (5) and 63.923(d)(4) and (5) shall not apply for the 

purposes of this subpart.

(ii) As an alternative to meeting the requirements in 

paragraph (b)(1)(i) of this section, an owner or operator may 

choose to control air emissions from the container in accordance 

with the standards for either Container Level 2 controls or 

Container Level 3 controls as specified in 40 CFR part 63, 

subpart PP—National Emission Standards for Containers, except 

that §§ 63.922(d)(4) and (5) and 63.923(d)(4) and (5) shall not 

apply for the purposes of this subpart.

* * * * *
Page 142 of 180

(3) * * *

(i) The owner or operator controls air emissions from the 

container in accordance with the standards for Container Level 2 

controls as specified in 40 CFR part 63, subpart PP—National 

Emission Standards for Containers, except that §§ 63.922(d)(4) 

and (5) and 63.923(d)(4) and (5) shall not apply for the 

purposes of this subpart.

* * * * *

10. Section 63.689 is amended by revising paragraph (d)(5) 

to read as follows:

§ 63.689 Standards: Transfer systems.

* * * * *

(d) * * *

(5) Whenever an off-site material is in the transfer 

system, the cover shall be installed with each closure device 

secured in the closed position, except the opening of closure 

devices or removal of the cover is allowed to provide access to 

the transfer system for performing routine inspection, 

maintenance, repair, or other activities needed for normal 

operations. Examples of such activities include those times when 

a worker needs to open a hatch or remove the cover to repair 

conveyance equipment mounted under the cover or to clear a 

blockage of material inside the system. Following completion of 

the activity, the owner or operator shall promptly secure the 
Page 143 of 180

closure device in the closed position or reinstall the cover, as 

applicable. 

* * * * *

11. Section 63.691 is amended by:

a. Revising paragraph (b); and

b. Adding paragraph (c) to read as follows:

§ 63.691 Standards: Equipment leaks.

* * * * * 

(b) According to the date an affected source commenced 

construction or reconstruction and the date an affected source 

receives off-site material for the first time, as established in 

§ 63.680(e)(i) through (iii) of this subpart, the owner or 

operator shall control the HAP emitted from equipment leaks in 

accordance with the applicable provisions specified in either 

paragraph (b)(1) or (2) of this section.

(1)(i) The owner or operator controls the HAP emitted from 

equipment leaks in accordance with §§ 61.241 through 61.247 in 

40 CFR part 61, subpart V—National Emission Standards for 

Equipment Leaks, with the difference noted in paragraphs 

(b)(1)(iii) and (iv) of this section for the purposes of this 

subpart; or 

(ii) The owner or operator controls the HAP emitted from 

equipment leaks in accordance with §§ 63.161 through 63.182 in 

40 CFR part 63, subpart H—National Emission Standards for 
Page 144 of 180

Organic Hazardous Air Pollutants from Equipment Leaks, with the 

differences noted in paragraphs (b)(2)(i) through (iv) of this 

section for the purposes of this subpart.

(iii) On or after [insert date of publication in the 

Federal Register], for the purpose of complying with the 

requirements of 40 CFR 61.242-6(a)(2) or the requirements of 40 

CFR 63.167(a)(2), the open end is sealed when instrument 

monitoring of the open-ended valve or line conducted according 

to Method 21 of 40 CFR part 60, appendix A indicates no readings 

of 500 ppm or greater.

(iv) On or after [insert date of publication in the Federal 

Register], for the purpose of complying with the requirements of 

40 CFR 61.242-6(d) or the requirements of 40 CFR 63.167(d), 

open-ended valves or lines in an emergency shutdown system which 

are designed to open automatically in the event of a process 

upset and that are exempt from the requirements in 40 CFR 

61.242-6(a), (b), and (c) or 40 CFR 63.167(a), (b), and (c) must 

comply with the requirements in § 63.693(c)(2) of this subpart.

(2) The owner or operator controls the HAP emitted from 

equipment leaks in accordance with §§ 63.161 through 63.183 in 

40 CFR part 63, subpart H – National Emission Standards for 

Organic Hazardous Air Pollutants for Equipment Leaks, with the 

differences noted in paragraphs (b)(2)(i) through (v) of this 

section for the purposes of this subpart. 
Page 145 of 180

(i) For each valve in gas/vapor or in light liquid service, 

as defined in § 63.681 of this subpart, that is part of an 

affected source under this subpart, an instrument reading that 

defines a leak is 500 ppm or greater as detected by Method 21 of 

40 CFR part 60, appendix A.

(ii) For each pump in light liquid service, as defined in 

§ 63.681 of this subpart, that is part of an affected source 

under this subpart, an instrument reading that defines a leak is 

1,000 ppm or greater as detected by Method 21 of 40 CFR part 60, 

appendix A. Repair is not required unless an instrument reading 

of 2,000 ppm or greater is detected.

(iii) On or after [insert date of publication in the 

Federal Register], for the purpose of complying with the 

requirements of 40 CFR 63.167(a)(2), the open end is sealed when 

instrument monitoring of the open-ended valve or line conducted 

according to Method 21 of 40 CFR part 60, appendix A indicates 

no readings of 500 ppm or greater.

(iv) On or after [insert date of publication in the Federal 

Register], for the purpose of complying with the requirements of 

40 CFR 63.167(d), open-ended valves or lines in an emergency 

shutdown system which are designed to open automatically in the 

event of a process upset and that are exempt from the 

requirements in 40 CFR 63.167(a), (b), and (c) must comply with 

the requirements in § 63.693(c)(2) of this subpart.
Page 146 of 180

(v) For the purposes of this subpart, the pressure relief 

device requirements of § 63.691(c) of this subpart rather than 

those of 40 CFR 63.165 or of 40 CFR 61.242-4, as applicable, 

shall apply. The pressure relief device requirements of 

§ 63.691(c)(3) and (4) of this subpart apply in addition to the 

requirements of 40 CFR 63.169 or of 40 CFR 61.242-8, as 

applicable, for pressure relief devices in liquid service. 

(c) Requirements for pressure relief devices. Except as 

provided in paragraph (c)(4) of this section, the owner or 

operator must comply with the requirements specified in 

paragraphs (c)(1) through (3) of this section for pressure 

relief devices in off-site material service.

(1) Operating requirements. Except during a pressure 

release event, operate each pressure relief device in gas/vapor 

service with an instrument reading of less than 500 ppm above 

background as detected by Method 21 of 40 CFR part 60, appendix 

A.

(2) Pressure release requirements. For pressure relief 

devices in gas/vapor service, the owner or operator must comply 

with either paragraph (c)(2)(i) or (ii) of this section 

following a pressure release, as applicable.

(i) If the pressure relief device does not consist of or 

include a rupture disk, the pressure relief device shall be 

returned to a condition indicated by an instrument reading of 
Page 147 of 180

less than 500 ppm above background, as detected by Method 21 of 

40 CFR part 60, appendix A, no later than 5 calendar days after 

the pressure release device returns to off-site material service 

following a pressure release, except as provided in 40 CFR 

63.171. 

(ii) If the pressure relief device consists of or includes 

a rupture disk, except as provided in 40 CFR 63.171, install a 

replacement disk as soon as practicable but no later than 5 

calendar days after the pressure release.

(3) Pressure release management. Except as provided in 

paragraph (c)(4) of this section, emissions of HAP listed in 

Table 1 of this subpart may not be discharged directly to the 

atmosphere from pressure relief devices in off-site material 

service, and according to the date an affected source commenced 

construction or reconstruction and the date an affected source 

receives off-site material for the first time, as established in 

§ 63.680(e)(1)(i) through (iii) of this subpart, the owner or 

operator must comply with the requirements specified in 

paragraphs (c)(3)(i) and (ii) of this section for all pressure 

relief devices in off-site material service.

(i) The owner or operator must equip each pressure relief 

device in off-site material service with a device(s) or use a 

monitoring system. The device or monitoring system may be either 

specific to the pressure release device itself or may be 
Page 148 of 180

associated with the process system or piping, sufficient to 

indicate a pressure release to the atmosphere. Examples of these 

types of devices or monitoring systems include, but are not 

limited to, a rupture disk indicator, magnetic sensor, motion 

detector on the pressure relief valve stem, flow monitor, 

pressure monitor, or parametric monitoring system. The devices 

or monitoring systems must be capable of meeting the 

requirements specified in paragraphs (c)(3)(i)(A) through (C) of 

this section.

(A) Identifying the pressure release; 

(B) Recording the time and duration of each pressure 

release; and 

(C) Notifying operators immediately that a pressure release 

is occurring.

(ii) If any pressure relief device in off-site material 

service releases directly to the atmosphere as a result of a 

pressure release event, the owner or operator must calculate the 

quantity of HAP listed in Table 1 of this subpart released 

during each pressure release event and report this quantity as 

required in § 63.697(b)(5) of this subpart. Calculations may be 

based on data from the pressure relief device monitoring alone 

or in combination with process parameter monitoring data and 

process knowledge. 
Page 149 of 180

(4) Pressure relief devices routed to a drain system, fuel 

gas system, process or control device. If a pressure relief 

device in off-site material service is designed and operated to 

route all pressure releases through a closed vent system to a 

drain system, fuel gas system, process or control device, 

paragraphs (c)(1), (2), and (3) of this section do not apply. 

The fuel gas system or closed vent system and the process or 

control device (if applicable) must meet the requirements of 

§ 63.693 of this subpart. The drain system (if applicable) must 

meet the requirements of § 63.689 of this subpart.

12. Section 63.693 is amended by:

a. Revising paragraphs (b)(3) and (8), (c)(1)(ii), and 

(c)(2) introductory text;

b. Adding paragraph (c)(2)(iii); and

c. Revising paragraphs (f)(1)(i)(B), (f)(1)(ii)(B), and 

(f)(2) introductory text;

d. Adding paragraph (f)(2)(iii);

e. Revising paragraphs (g)(1)(v) and (g)(2)(i); and

f. Adding paragraph (g)(2)(i)(C) to read as follows:

§ 63.693 Standards: Closed-vent systems and control devices.

* * * * *

(b) * * *

(3) Whenever gases or vapors containing HAP are routed from 

a tank through a closed-vent system connected to a control 
Page 150 of 180

device used to comply with the requirements of § 63.685(b)(1), 

(2), or (3) of this subpart, the control device must be 

operating except as provided for in paragraphs (b)(3)(i) and 

(ii) of this section.

(i) The control device may only be bypassed for the purpose 

of performing planned routine maintenance of the closed-vent 

system or control device in situations when the routine 

maintenance cannot be performed during periods that tank 

emissions are vented to the control device.

(ii) On an annual basis, the total time that the closedvent system or control device is bypassed to perform routine 

maintenance shall not exceed 240 hours per each calendar year. 

* * * * *

(8) In the case when an owner or operator chooses to use a 

design analysis to demonstrate compliance of a control device 

with the applicable performance requirements specified in this 

section as provided for in paragraphs (d) through (g) of this 

section, the Administrator may require that the design analysis 

be revised or amended by the owner or operator to correct any 

deficiencies identified by the Administrator. If the owner or 

operator and the Administrator do not agree on the acceptability 

of using the design analysis (including any changes required by 

the Administrator) to demonstrate that the control device 

achieves the applicable performance requirements, then the 
Page 151 of 180

disagreement must be resolved using the results of a performance 

test conducted by the owner or operator in accordance with the 

requirements of § 63.694(l) of this subpart. The Administrator 

may choose to have an authorized representative observe the 

performance test conducted by the owner or operator. Should the 

results of this performance test not agree with the 

determination of control device performance based on the design 

analysis, then the results of the performance test will be used 

to establish compliance with this subpart.

* * * * *

(c) * * *

(1) * * *

(ii) A closed-vent system that is designed to operate at a 

pressure below atmospheric pressure. The system shall be 

equipped with at least one pressure gauge or other pressure 

measurement device that can be read from a readily accessible 

location to verify that negative pressure is being maintained in 

the closed-vent system when the control device is operating.

(2) In situations when the closed-vent system includes 

bypass devices that could be used to divert a vent stream from 

the closed-vent system to the atmosphere at a point upstream of 

the control device inlet, each bypass device must be equipped 

with either a flow indicator as specified in paragraph (c)(2)(i) 

of this section or a seal or locking device as specified in 
Page 152 of 180

paragraph (c)(2)(ii) of this section, except as provided for in 

paragraph (c)(2)(iii) of this section:

* * * * *

(iii) Equipment needed for safety reasons, including low 

leg drains, open-ended valves and lines not in emergency 

shutdown systems, and pressure relief devices subject to the 

requirements of § 63.691(c) of this subpart are not subject to 

the requirements of paragraphs (c)(2)(i) and (ii) of this 

section.

* * * * *

(f) * * *

(1) * * *

(i) * * *

(B) To achieve a total incinerator outlet concentration for 

the TOC, less methane and ethane, of less than or equal to 20 

ppmv on a dry basis corrected to 3 percent oxygen.

(ii) * * *

(B) To achieve a total incinerator outlet concentration for 

the HAP, listed in Table 1 of this subpart, of less than or 

equal to 20 ppmv on a dry basis corrected to 3 percent oxygen.

* * * * *

(2) The owner or operator must demonstrate that the vapor 

incinerator achieves the performance requirements in paragraph 

(f)(1) of this section by conducting either a performance test 
Page 153 of 180

as specified in paragraph (f)(2)(i) of this section or a design 

analysis as specified in paragraph (f)(2)(ii) of this section, 

except as provided for in paragraph (f)(2)(iii) of this section.

* * * * *

(iii) An owner or operator is not required to conduct a 

performance test or design analysis if the incinerator has been 

issued a final permit under 40 CFR part 270 and complies with 

the requirements of 40 CFR part 264, subpart O, or has certified 

compliance with the interim status requirements of 40 CFR part 

265, subpart O.

(g) * * *

(1) * * *

(v) Introduce the vent stream to a boiler or process heater 

for which the owner or operator either has been issued a final 

permit under 40 CFR part 270 and complies with the requirements 

of 40 CFR part 266, subpart H; or has certified compliance with 

the interim status requirements of 40 CFR part 266, subpart H; 

or has submitted a Notification of Compliance under 40 CFR 

63.1207(j) and 63.1210(d) and complies with the requirements of 

40 CFR part 63, subpart EEE at all times (including times when 

non-hazardous waste is being burned).

(2) * * *

(i) If an owner or operator chooses to comply with the 

performance specifications in either paragraph (g)(1)(i), (ii), 
Page 154 of 180

or (iii) of this section, the owner or operator must demonstrate 

compliance with the applicable performance specifications by 

conducting either a performance test as specified in paragraph 

(g)(2)(i)(A) of this section or a design analysis as specified 

in paragraph (g)(2)(i)(B) of this section, except as provided 

for in paragraph (g)(2)(i)(C) of this section.

* * * * *

(C) An owner or operator is not required to conduct a 

performance test or design analysis if the boiler or process 

heater has been issued a final permit under 40 CFR part 270 and 

complies with the requirements of 40 CFR part 266, subpart H; or 

has certified compliance with the interim status requirements of 

40 CFR part 266, subpart H.

* * * * *

13. Section 63.694 is amended by revising paragraphs 

(b)(3)(iv), (f)(1), (i)(1), (j)(3), (k)(3), (l) introductory 

text, (l)(2), (l)(3) introductory text, (l)(3)(i), 

(l)(3)(ii)(B), (l)(4) introductory text, (l)(4)(i), 

(l)(4)(ii)(A) and (B), (l)(4)(iii)(A), and (m)(2) and (3) to 

read as follows:

§ 63.694 Testing methods and procedures.

* * * * *

(b) * * *

(3) * * *
Page 155 of 180

(iv) In the event that the Administrator and the owner or 

operator disagree on a determination of the average VOHAP 

concentration for an off-site material stream using knowledge, 

then the results from a determination of VOHAP concentration 

using direct measurement as specified in paragraph (b)(2) of 

this section shall be used to establish compliance with the 

applicable requirements of this subpart. The Administrator may 

perform or require that the owner or operator perform this 

determination using direct measurement. 

(f) * * *

(1) The actual HAP mass removal rate (MR) shall be 

determined based on results for a minimum of three consecutive 

runs. The sampling time for each run shall be at least 1 hour.

* * * * *

(i) * * *

(1) The actual HAP mass removal rate (MRbio) shall be 

determined based on results for a minimum of three consecutive 

runs. The sampling time for each run shall be at least 1 hour.

* * * * *

(j) * * *

(3) Use of knowledge to determine the maximum HAP vapor 

pressure of the off-site material. Documentation shall be 

prepared and recorded that presents the information used as the 

basis for the owner's or operator's knowledge that the maximum 
Page 156 of 180

HAP vapor pressure of the off-site material is less than the 

maximum vapor pressure limit listed in Table 3, Table 4, or 

Table 5 of this subpart for the applicable tank design capacity 

category. Examples of information that may be used include: the 

off-site material is generated by a process for which at other 

locations it previously has been determined by direct 

measurement that the off-site material maximum HAP vapor 

pressure is less than the maximum vapor pressure limit for the 

appropriate tank design capacity category. In the event that the 

Administrator and the owner or operator disagree on a 

determination of the maximum HAP vapor pressure for an off-site 

material stream using knowledge, then the results from a 

determination of HAP vapor pressure using direct measurement as 

specified in paragraph (j)(2) of this section shall be used to 

establish compliance with the applicable requirements of this 

subpart. The Administrator may perform or require that the owner 

or operator perform this determination using direct measurement.

(k) * * *

(3) The detection instrument shall meet the performance 

criteria of Method 21 of 40 CFR part 60, appendix A, except the 

instrument response factor criteria in section 8.1.1 of Method 

21 shall be for the weighted average composition of the organic 

constituents in the material placed in the unit at the time of 

monitoring, not for each individual organic constituent.
Page 157 of 180

* * * * *

(l) Control device performance test procedures. Performance 

tests shall be based on representative performance (i.e., 

performance based on normal operating conditions)and shall 

exclude periods of startup and shutdown unless specified by the 

Administrator. The owner or operator may not conduct performance 

tests during periods of malfunction. The owner or operator must 

record the process information that is necessary to document 

operating conditions during the test and include in such record 

an explanation to support that such conditions represent normal 

operation. Upon request, the owner or operator shall make 

available to the Administrator such records as may be necessary 

to determine the conditions of performance tests.

* * * * *

(2) The gas volumetric flow rate shall be determined using 

Method 2, 2A, 2C, or 2D, 2F, or 2G of 40 CFR part 60, appendix 

A, as appropriate.

(3) To determine compliance with the control device 

percent reduction requirement, the owner or operator shall use 

Method 18 of 40 CFR part 60, appendix A to measure the HAP in 

Table 1 of this subpart or Method 25A of 40 CFR part 60, 

appendix A to measure TOC. Method 18 may be used to measure 

methane and ethane, and the measured concentration may be 

subtracted from the Method 25A measurement. Alternatively, any 
Page 158 of 180

other method or data that has been validated according to the 

applicable procedures in Method 301 in 40 CFR part 63, appendix 

A may be used. The following procedures shall be used to 

calculate percent reduction efficiency: 

(i) A minimum of three sample runs must be performed. The 

minimum sampling time for each run shall be 1 hour. For Method 

18, either an integrated sample or a minimum of four grab 

samples shall be taken. If grab sampling is used, then the 

samples shall be taken at approximately equal intervals in time 

such as 15 minute intervals during the run. 

(ii) * * *

(B) When the TOC mass rate is calculated, the average 

concentration reading (minus methane and ethane) measured by 

Method 25A of 40 CFR part 60, appendix A shall be used in the 

equation in paragraph (l)(3)(ii)(A) of this section. 

* * * * *

(4) To determine compliance with the enclosed combustion 

device total HAP concentration limit of this subpart, the owner 

or operator shall use Method 18 of 40 CFR part 60, appendix A to 

measure the total HAP in Table 1 of this subpart or Method 25A 

of 40 CFR part 60, appendix A to measure TOC. Method 18 may be 

used to measure methane and ethane and the measured 

concentration may be subtracted from the Method 25A measurement. 

Alternatively, any other method or data that has been validated 
Page 159 of 180

according to Method 301 in appendix A of this part, may be used. 

The following procedures shall be used to calculate parts per 

million by volume concentration, corrected to 3 percent oxygen:

(i) A minimum of three sample runs must be performed. The 

minimum sampling time for each run shall be 1 hour. For Method 

18, either an integrated sample or a minimum of four grab 

samples shall be taken. If grab sampling is used, then the 

samples shall be taken at approximately equal intervals in time, 

such as 15 minute intervals during the run. 

(ii) * * *

(A) The TOC concentration (CTOC) is the average 

concentration readings provided by Method 25 A of 40 CFR part 

60, appendix A, minus the concentration of methane and ethane.

(B) The total HAP concentration (CHAP) shall be computed 

according to the following equation:

 = 

∑ 











where:

CHAP = Total concentration of HAP compounds listed in Table 1 of 

this subpart, dry basis, parts per million by volume.

Cij = Concentration of sample components j of sample i, dry 

basis, parts per million by volume.
Page 160 of 180

n = Number of components in the sample.

x = Number of samples in the sample run.

(iii) * * *

(A) The emission rate correction factor or excess air, 

integrated sampling and analysis procedures of Method 3B of 40 

CFR part 60, appendix A shall be used to determine the oxygen 

concentration (%O2dry). Alternatively, the owner or operator may 

use Method 3A of 40 CFR part 60, appendix A to determine the 

oxygen concentration. The samples shall be collected during the 

same time that the samples are collected for determining TOC 

concentration or total HAP concentration. 

* * * * *

(m) * * *

(2) No traverse site selection method is needed for vents 

smaller than 0.10 meter in diameter. For vents smaller than 0.10 

meter in diameter, sample at the center of the vent.

(3) Process vent stream gas volumetric flow rate must be 

determined using Method 2, 2A, 2C, 2D, 2F, or 2G of 40 CFR part 

60, appendix A, as appropriate.

* * * * *

14. Section 63.695 is amended by:

a. Revising paragraph (a) introductory text;

b. Adding paragraph (a)(5);
Page 161 of 180

c. Revising paragraph (e) introductory text, (e)(4) and 

(5); and

d. Removing paragraphs (e)(6) and (7) to read as follows:

§ 63.695 Inspection and monitoring requirements.

(a) The owner or operator must install, calibrate, 

maintain, and operate all monitoring system components according 

to §§ 63.8 of this part, 63.684(e), 63.693(d)(3), (e)(3), 

(f)(3), (g)(3), and (h)(3) of this subpart, and paragraph (5) of 

this section and perform the inspection and monitoring 

procedures specified in paragraphs (a)(1) through (4) of this 

section.

* * * * *

(5)(i) Except for periods of monitoring system 

malfunctions, repairs associated with monitoring system 

malfunctions and required monitoring system quality assurance or 

quality control activities (including, as applicable, 

calibration checks and required zero and span adjustments), the 

owner or operator must operate the continuous monitoring system 

at all times the affected source is operating. A monitoring 

system malfunction is any sudden, infrequent, not reasonably 

preventable failure of the monitoring system to provide data. 

Monitoring system failures that are caused in part by poor 

maintenance or careless operation are not malfunctions. The 

owner or operator is required to complete monitoring system 
Page 162 of 180

repairs in response to monitoring system malfunctions and to 

return the monitoring system to operation as expeditiously as 

practicable.

(ii) The owner or operator may not use data recorded during 

monitoring system malfunctions, repairs associated with 

monitoring system malfunctions, or required monitoring system 

quality assurance or control activities in calculations used to 

report emissions or operating levels. The owner or operator must 

use all the data collected during all other required data 

collection periods in assessing the operation of the control 

device and associated control system. The owner or operator must 

report any periods for which the monitoring system failed to 

collect required data.

* * * * *

(e) Control device monitoring requirements. For each 

control device required under § 63.693 of this subpart to be 

monitored in accordance with the provisions of this paragraph 

(e), the owner or operator must ensure that each control device 

operates properly by monitoring the control device in accordance 

with the requirements specified in paragraphs (e)(1) through (5) 

of this section.

* * * * *

(4) A deviation for a given control device is determined to 

have occurred when the monitoring data or lack of monitoring 
Page 163 of 180

data result in any one of the criteria specified in paragraphs 

(e)(4)(i) through (iii) of this section being met. When multiple 

operating parameters are monitored for the same control device 

and during the same operating day more than one of these 

operating parameters meets a deviation criterion specified in 

paragraphs (e)(4)(i) through (iii) of this section, then a 

single deviation is determined to have occurred for the control 

device for that operating day.

(i) A deviation occurs when the daily average value of a 

monitored operating parameter is less than the minimum operating 

parameter limit (or, if applicable, greater than the maximum 

operating parameter limit) established for the operating 

parameter in accordance with the requirements of paragraph 

(e)(3) of this section.

(ii) A deviation occurs when the period of control device 

operation is 4 hours or greater in an operating day and the 

monitoring data are insufficient to constitute a valid hour of 

data for at least 75 percent of the operating hours. Monitoring 

data are insufficient to constitute a valid hour of data if 

measured values are unavailable for any of the 15-minute periods 

within the hour.

(iii) A deviation occurs when the period of control device 

operation is less than 4 hours in an operating day and more than 

1 of the hours during the period does not constitute a valid 
Page 164 of 180

hour of data due to insufficient monitoring data. Monitoring 

data are insufficient to constitute a valid hour of data if 

measured values are unavailable for any of the 15-minute periods 

within the hour.

(5) For each deviation, except when the deviation occurs 

during periods of non-operation of the unit or the process that 

is vented to the control device (resulting in cessation of HAP 

emissions to which the monitoring applies), the owner or 

operator shall be deemed to have failed to have applied control 

in a manner that achieves the required operating parameter 

limits. Failure to achieve the required operating parameter 

limits is a violation of this standard.

* * * * *

15. Section 63.696 is amended by revising paragraph (h) and 

adding paragraphs (i) and (j) to read as follows:

63.696 Recordkeeping requirements.

* * * * *

(h) An owner or operator shall record the malfunction 

information specified in paragraphs (h)(1) through (3) of this 

section.

(1) In the event that an affected unit fails to meet an 

applicable standard, record the number of failures. For each 

failure, record the date, time and duration of the failure.
Page 165 of 180

(2) For each failure to meet an applicable standard, record 

and retain a list of the affected sources or equipment, an 

estimate of the volume of each regulated pollutant emitted over 

any emission limit and a description of the method used to 

estimate the emissions. 

(3) Record actions taken to minimize emissions in 

accordance with § 63.683(e) of this subpart and any corrective 

actions taken to return the affected unit to its normal or usual 

manner of operation.

(i) For pressure relief devices in off-site material 

service, keep records of the information specified in paragraphs 

(i)(1) through (5) of this section, as applicable.

(1) A list of identification numbers for pressure relief 

devices that the owner or operator elects to route emissions 

through a closed-vent system to a control device, process or 

drain system under the provisions in § 63.691(c)(4) of this 

subpart.

(2) A list of identification numbers for pressure relief 

devices that do not consist of or include a rupture disk, 

subject to the provisions in § 63.691(c)(2)(i) of this subpart.

(3) A list of identification numbers for pressure relief 

devices equipped with rupture disks, subject to the provisions 

in § 63.691(c)(2)(ii) of this subpart.
Page 166 of 180

(4) The dates and results of the Method 21 of 40 CFR part 

60, appendix A, monitoring following a pressure release for each 

pressure relief device subject to the provisions in 

§ 63.691(c)(2)(i) of this subpart. The results of each 

monitoring event shall include:

(i) The measured background level.

(ii) The maximum instrument reading measured at each 

pressure relief device.

(5) For pressure relief devices in off-site material 

service subject to § 63.691(c)(3) of this subpart, keep records 

of each pressure release to the atmosphere, including the 

following information:

(i) The source, nature, and cause of the pressure release.

(ii) The date, time, and duration of the pressure release.

(iii) An estimate of the quantity of HAP listed in Table 1 

of this subpart emitted during the pressure release and the 

calculations used for determining this quantity.

(iv) The actions taken to prevent this pressure release.

(v) The measures adopted to prevent future such pressure 

releases.

(j) (1) For pressure tank closure devices, as specified in 

§ 63.685(h)(2) of this subpart, keep records of each release to 

the atmosphere, including the information specified in 

paragraphs (j)(3) though (7) of this section.
Page 167 of 180

(2) For each closed vent system that includes bypass 

devices that could divert a stream away from the control device 

and into the atmosphere, as specified in § 63.693(c)(2) of this 

subpart, and each open-ended valve or line in an emergency 

shutdown system which is designed to open automatically in the 

event of a process upset, as specified in 40 CFR 63.167(d) or 40 

CFR 61.242-6(d), keep records of each release to the atmosphere, 

including the information specified in paragraphs (j)(3) though 

(9) of this section.

(3) The source, nature, and cause of the release.

(4) The date, time, and duration of the release.

(5) An estimate of the quantity of HAP listed in Table 1 of 

this subpart emitted during the release and the calculations 

used for determining this quantity.

(6) The actions taken to prevent this release.

(7) The measures adopted to prevent future such release.

(8) Hourly records of whether the bypass flow indicator 

specified under § 63.693(c)(2) of this subpart was operating and 

whether a diversion was detected at any time during the hour, as 

well as records of the times of all periods when the vent stream 

is diverted from the control device or the flow indicator is not 

operating.

(9) Where a seal mechanism is used to comply with 

§ 63.693(c)(2) of this subpart, hourly records of flow are not 
Page 168 of 180

required. In such cases, the owner or operator shall record that 

the monthly visual inspection of the seals or closure mechanism 

has been done, and shall record the duration of all periods when 

the seal mechanism is broken, the bypass line valve position has 

changed, or the key for a lock-and-key type lock has been 

checked out, and records of any car-seal that has broken.

16. Section 63.697 is amended by:

a. Revising paragraph (a) introductory text, adding 

paragraphs (a)(1)(i) and (ii) and (a)(3); 

b. Revising paragraph (b)(3) and (4); and

c. Adding paragraphs (b)(5) and (6) to read as follows:

§ 63.697 Reporting requirements.

(a) Each owner or operator of an affected source subject to 

this subpart must comply with the notification requirements 

specified in paragraph (a)(1) of this section and the reporting 

requirements specified in paragraphs (a)(2) and (3) of this 

section.

(1) * * *

(i) For pressure relief devices in off-site material

service subject to the requirements of § 63.691(c) of this 

subpart, the owner or operator must submit the information 

listed in paragraph (a)(1)(ii) of this section in the 

notification of compliance status required under § 63.9(h) of 
Page 169 of 180

this part within 150 days after the first applicable compliance 

date for pressure relief device monitoring.

(ii) For pressure relief devices in off-site material

service, a description of the device or monitoring system to be 

implemented, including the pressure relief devices and process 

parameters to be monitored (if applicable), a description of the 

alarms or other methods by which operators will be notified of a 

pressure release, and a description of how the owner or operator 

will determine the information to be recorded under 

§ 63.696(i)(5)(ii) through (iii) of this subpart (i.e., the 

duration of the pressure release and the methodology and 

calculations for determining the quantity of HAP listed in Table 

1 of this subpart emitted during the pressure release).

* * * * *

(3) Electronic reporting. Within 60 days after the date of 

completing each performance test (as defined in § 63.2 of this 

part) required by this subpart, the owner or operator must 

submit the results of the performance test according to the 

manner specified by either paragraph (a)(3)(i) or (ii) of this 

section.

(i) For data collected using test methods supported by the 

EPA’s Electronic Reporting Tool (ERT) as listed on the EPA’s ERT 

Web site (http://www.epa.gov/ttn/chief/ert/index.html), the 

owner or operator must submit the results of the performance 
Page 170 of 180

test to the EPA via the Compliance and Emissions Data Reporting 

Interface (CEDRI) accessed through the EPA’s Central Data 

Exchange (CDX) (http://cdx.epa.gov/epa_home.asp). Performance 

test data must be submitted in a file format generated through 

the use of the EPA’s ERT. Owners or operators who claim that 

some of the performance test information being submitted is 

confidential business information (CBI) must submit a complete 

file generated through the use of the EPA’s ERT, including 

information claimed to be CBI, on a compact disc, flash drive, 

or other commonly used electronic storage media to the EPA. The 

electronic media must be clearly marked as CBI and mailed to 

U.S. EPA/OAPQS/CORE CBI Office, Attention: Group Leader, 

Measurement Policy Group, MD C404-02, 4930 Old Page Road, 

Durham, NC 27703. The same ERT file with the CBI omitted must be 

submitted to the EPA via the EPA’s CDX as described earlier in 

this paragraph (a)(3)(i).

(ii) For data collected using test methods that are not 

supported by the EPA’s ERT as listed on the EPA’s ERT Web site, 

the owner or operator must submit the results of the performance 

test to the Administrator at the appropriate address listed in 

40 CFR 60.4. 

(b) * * * 

(3) Reports of malfunctions. If a source fails to meet an 

applicable standard, report such events in the Periodic Report. 
Page 171 of 180

Report the number of failures to meet an applicable standard. 

For each instance, report the date, time and duration of each 

failure. For each failure the report must include a list of the 

affected sources or equipment, an estimate of the volume of each 

regulated pollutant emitted over any emission limit, and a 

description of the method used to estimate the emissions. 

(4) A summary report specified in § 63.10(e)(3) of this 

part shall be submitted on a semiannual basis (i.e., once every 

6-month period). The summary report must include a description 

of all deviations as defined in § 63.683(f) and § 63.695(e) of 

this subpart that have occurred during the 6-month reporting 

period. For each deviation caused when the daily average value 

of a monitored operating parameter is less than the minimum 

operating parameter limit (or, if applicable, greater than the 

maximum operating parameter limit), the report must include the 

daily average values of the monitored parameter, the applicable 

operating parameter limit, and the date and duration of the 

period that the deviation occurred. For each deviation caused by 

lack of monitoring data, the report must include the date and 

duration of period when the monitoring data were not collected 

and the reason why the data were not collected.

(5) For pressure relief devices in off-site material 

service subject to § 63.691(c) of this subpart, Periodic Reports 
Page 172 of 180

must include the information specified in paragraphs (b)(5)(i) 

through (iii) of this section.

(i) For pressure relief devices in off-site material 

service subject to § 63.691(c) of this subpart, report the 

results of all monitoring conducted within the reporting period.

(ii) For pressure relief devices in gas/vapor service 

subject to § 63.691(c)(2)(i) of this subpart, report any 

instrument reading of 500 ppm above background or greater, if 

detected more than 5 days after the pressure release.

(iii) For pressure relief devices in off-site material 

service subject to § 63.691(c)(3) of this subpart, report each 

pressure release to the atmosphere, including the following 

information:

(A) The source, nature, and cause of the pressure release.

(B) The date, time, and duration of the pressure release.

(C) An estimate of the quantity of HAP listed in Table 1 of 

this subpart emitted during the pressure release and the method 

used for determining this quantity.

(D) The actions taken to prevent this pressure release.

(E) The measures adopted to prevent future such pressure 

releases.

(6) Pressure tank closure device or bypass deviation 

report. The owner or operator must submit to the Administrator 

the information specified in paragraph (b)(6)(iv) of this 
Page 173 of 180

section when any of the conditions in paragraphs (b)(6)(i) 

through (iii) of this section are met. 

(i) Any pressure tank closure device, as specified in 

§ 63.685(h)(2) of this subpart, has released to the atmosphere.

(ii) Any closed vent system that includes bypass devices 

that could divert a vent a stream away from the control device 

and into the atmosphere, as specified in § 63.693(c)(2) of this 

subpart, has released directly to the atmosphere.

(iii) Any open-ended valve or line in an emergency shutdown 

system which is designed to open automatically in the event of a 

process upset, as specified in 40 CFR 63.167(d) or 40 CFR 

61.242-6(d), has released directly to the atmosphere.

(iv) The pressure tank closure device or bypass deviation 

report must include the information specified in paragraphs 

(b)(6)(iv)(A) through (E) of this section.

(A) The source, nature and cause of the release.

(B) The date, time and duration of the discharge.

(C) An estimate of the quantity of HAP listed in Table 1 of 

this subpart emitted during the release and the method used for 

determining this quantity.

(D) The actions taken to prevent this release.

(E) The measures adopted to prevent future such releases.

* * * * *
Page 174 of 180

17. Section 63.698 is amended by revising paragraph (c) 

introductory text and adding paragraph (c)(5) to read as 

follows: 

§ 63.698 Implementation and enforcement.

* * * * *

(c) The authorities that cannot be delegated to State, 

local, or Tribal agencies are as specified in paragraphs (c)(1) 

through (5) of this section.

* * * * *

(5) Approval of alternatives to the electronic reporting 

requirements in § 63.697(a)(3).

18. Table 2 to subpart DD of part 63 is amended by:

a. Removing entries 63.1(a)(13) and 63.1(a)(14);

b. Revising entries 63.1(b)(2), 63.1(c)(3), and 63.1(c)(4);

c. Removing entry 63.4(a)(1) through 63.4(a)(3) and adding 

entries 63.4(a)(1)–63.4(a)(2) and 63.4(a)(3);

d. Revising entries 63.4(a)(5) and 63.5(a)(1);

e. Revising entries 63.5(b)(5), 63.6(b)(3), 63.6(b)(4);

f. Removing entry 63.6(e) and adding entries 63.6(e)(1)(i) 

through 63.6(e)(1)(iii), 63.6(e)(2), and 63.6(e)(3);

g. Revising entry 63.6(f)(1);

h. Adding entry 63.7(a)(4);

i. Revising entries 63.7(b), 63.7(c), 63.7(e)(1) and 

63.7(f);
Page 175 of 180

j. Revising entry 63.8(c)(1)(iii);

k. Revising entries 63.9(e) and 63.9(g);

l. Revising entries 63.10(b)(2)(i) through (v);

m. Removing entry 63.10(c) and adding entries 63.10(c)(1)-

(6), 63.10(c)(7)-(8), and 63.10(c)(9)-(15);

n. Removing entries 63.10(d)(5)(i) and 63.10(d)(5)(ii), and 

adding entry 63.10(d)(5); 

o. Removing entry 63.10(e) and adding entries 63.10(e)(1)-

63.10(e)(2), 63.10(e)(3), and 63.10(e)(4); and

p. Adding entry 63.16 to read as follows:

Table 2 to Subpart DD of Part 63—Applicability of Paragraphs in 

Subpart A of This Part 63—General Provisions to Subpart DD

Subpart A 

reference

Applies 

to 

Subpart 

DD

Explanation

* * * * * * *

63.1(b)(2) No Reserved.

* * * * * * *

63.1(c)(3) No Reserved.

63.1(c)(4) No Reserved.

* * * * * * *

63.4(a)(1)–

63.4(a)(2) Yes

63.4(a)(3) No Reserved.

* * * * * * *

63.4(a)(5) No Reserved.

* * * * * * *

63.5(a)(1) Yes

* * * * * * *

63.5(b)(5) No Reserved.

* * * * * * *
Page 176 of 180

63.6(b)(3) No

63.6(b)(4) No

* * * * * * *

63.6(e)(1)(i) No See § 63.683(e) of this subpart for 

general duty requirement.

63.6(e)(1)(ii) No

63.6(e)(1)(iii) Yes

63.6(e)(2) No Reserved.

63.6(e)(3) No

63.6(f)(1) No

* * * * * * *

63.7(a)(4) Yes

63.7(b) Yes

63.7(c) Yes

* * * * * * *

63.7(e)(1) No See § 63.694(l) of this subpart.

* * * * * * *

63.7(f) Yes

* * * * * * *

63.8(c)(1)(iii) No

* * * * * * *

63.9(e) Yes

* * * * * * *

63.9(g) Yes

* * * * * * *

63.10(b)(2)(i) No

63.10(b)(2)(ii) No

See § 63.696(h) of this subpart for 

recordkeeping of (1) date, time and 

duration; (2) listing of affected 

source or equipment, and an estimate 

of the volume of each regulated 

pollutant emitted over the standard; 

and (3) actions to minimize emissions 

and correct the failure.

63.10(b)(2)(iii) Yes

63.10(b)(2)(iv) No

63.10(b)(2)(v) No

* * * * * * *
Page 177 of 180

63.10(c)(1)-(6) No

63.10(c)(7)-(8) Yes

63.10(9)-(15) No

* * * * * * *

63.10(d)(5) No See § 63.697(b)(3) of this subpart for 

reporting of malfunctions.

63.10(e)(1) –

63.10(e)(2) No

63.10(e)(3) Yes

63.10(e)(4) No

* * * * * * *

63.16 No

* * * * *

19. Table 3 to subpart DD of part 63 is revised to read as 

follows:

Table 3 to Subpart DD of Part 63—Tank Control Levels for Tanks 

at Existing Affected Sources as Required by 40 CFR 

63.685(b)(1)(i)

Tank design 

capacity 

(cubic 

meters)

Maximum HAP vapor 

pressure of offsite material 

managed in tank 

(kilopascals) 

Tank control level 

Design 

capacity less 

than 75 m3

Maximum HAP vapor 

pressure less than 

76.6 kPa

Level 1. 

Design 

capacity less 

than 75 m3

Maximum HAP vapor 

pressure equal to 

or greater than 

76.6 kPa

Level 2, except that fixed 

roof tanks equipped with an 

internal floating roof and 

tanks equipped with an 

external floating roof as 

provided for in § 63.685(d)(1) 

and (2) of this subpart shall 

not be used.

Design 

capacity 

equal to or 

greater than 

75 m3 and less 

than 151 m3

Maximum HAP vapor 

pressure less than 

27.6 kPa

Level 1. 

 Maximum HAP vapor Level 2. 
Page 178 of 180

pressure equal to 

or greater than 

27.6 kPa

Design 

capacity 

equal to or 

greater than 

151 m3

Maximum HAP vapor 

pressure less than 

5.2 kPa

Level 1. 

 

Maximum HAP vapor 

pressure equal to 

or greater than 5.2 

kPa

Level 2.

20. Table 4 to subpart DD of part 63 is revised to read as 

follows:

Table 4 to Subpart DD of Part 63—Tank Control Levels for Tanks 

at Existing Affected Sources as Required by 40 CFR 

63.685(b)(1)(ii)

Tank design 

capacity 

(cubic 

meters)

Maximum HAP vapor 

pressure of offsite material 

managed in tank 

(kilopascals) 

Tank control level 

Design 

capacity less 

than 75 m3

Maximum HAP vapor 

pressure less than 

76.6 kPa

Level 1. 

Design 

capacity less 

than 75 m3

Maximum HAP vapor 

pressure equal to 

or greater than 

76.6 kPa

Level 2, except that fixed 

roof tanks equipped with an 

internal floating roof and 

tanks equipped with an 

external floating roof as 

provided for in § 63.685(d)(1) 

and (2) of this subpart shall 

not be used.

Design 

capacity 

equal to or 

greater than 

75 m3 and less 

than 151 m3

Maximum HAP vapor 

pressure less than 

13.1 kPa

Level 1. 

 

Maximum HAP vapor 

pressure equal to Level 2. 
Page 179 of 180

or greater than 

13.1 kPa

Design 

capacity 

equal to or 

greater than 

151 m3

Maximum HAP vapor 

pressure less than 

5.2 kPa

Level 1. 

 

Maximum HAP vapor 

pressure equal to 

or greater than 5.2 

kPa

Level 2.

21. Table 5 is added to subpart DD of part 63 to read as 

follows:

Table 5 to Subpart DD of Part 63—Tank Control Levels for Tanks 

at New Affected Sources as Required by 40 CFR 63.685(b)(2)

Tank design 

capacity 

(cubic 

meters)

Maximum HAP vapor 

pressure of offsite material 

managed in tank 

(kilopascals) 

Tank control level 

Design 

capacity less 

than 38 m3

Maximum HAP vapor 

pressure less than 

76.6 kPa

Level 1. 

Design 

capacity less 

than 38 m3

Maximum HAP vapor 

pressure equal to

or greater than 

76.6 kPa

Level 2, except that fixed 

roof tanks equipped with an 

internal floating roof and 

tanks equipped with an 

external floating roof as 

provided for in § 63.685(d)(1) 

and (2) of this subpart shall 

not be used.

Design 

capacity 

equal to or 

greater than 

38 m3 and less 

than 151 m3

Maximum HAP vapor 

pressure less than 

13.1 kPa

Level 1.

 

Maximum HAP vapor 

pressure equal to 

or greater than 

13.1 kPa

Level 2.

Design 

capacity 

Maximum HAP vapor 

pressure less than Level 1.
Page 180 of 180

equal to or 

greater than 

151 m3

0.7 kPa

 

Maximum HAP vapor 

pressure equal to 

or greater than 0.7 

kPa

Level 2.