Document ID: PHMSA-2021-0039-0020
Agency: phmsa
Document Type: Proposed Rule
Title: Pipeline Safety: Gas Pipeline Leak Detection and Repair
Posted Date: 2023-05-18T04:00Z

[Federal Register Volume 88, Number 96 (Thursday, May 18, 2023)]
[Proposed Rules]
[Pages 31890-31979]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2023-09918]

[[Page 31889]]

Vol. 88

Thursday,

No. 96

May 18, 2023

Part III

Department of Transportation

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Pipeline and Hazardous Materials Safety Administration

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49 CFR Parts 191, 192, and 193

Pipeline Safety: Gas Pipeline Leak Detection and Repair; Proposed Rule

  Federal Register / Vol. 88, No. 96 / Thursday, May 18, 2023 / 
Proposed Rules  

[[Page 31890]]

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DEPARTMENT OF TRANSPORTATION

Pipeline and Hazardous Materials Safety Administration

49 CFR Parts 191, 192, and 193

[Docket No. PHMSA-2021-0039]
RIN 2137-AF51

Pipeline Safety: Gas Pipeline Leak Detection and Repair

AGENCY: Pipeline and Hazardous Materials Safety Administration (PHMSA), 
Department of Transportation (DOT).

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: PHMSA proposes regulatory amendments that implement 
congressional mandates in the Protecting our Infrastructure of 
Pipelines and Enhancing Safety Act of 2020 to reduce methane emissions 
from new and existing gas transmission pipelines, distribution 
pipelines, regulated (Types A, B, C and offshore) gas gathering 
pipelines, underground natural gas storage facilities, and liquefied 
natural gas facilities. Among the proposed amendments for part 192-
regulated gas pipelines are strengthened leakage survey and patrolling 
requirements; performance standards for advanced leak detection 
programs; leak grading and repair criteria with mandatory repair 
timelines; requirements for mitigation of emissions from blowdowns; 
pressure relief device design, configuration, and maintenance 
requirements; and clarified requirements for investigating failures. 
Finally, PHMSA proposes expanded reporting requirements for operators 
of all gas pipeline facilities within DOT's jurisdiction, including 
underground natural gas storage facilities and liquefied natural gas 
facilities.

DATES: Written comments on this NPRM must be submitted by July 17, 
2023. The agency will, consistent with 49 CFR 190.323, consider late-
filed comments to the extent practicable.

ADDRESSES: You may submit comments identified by the docket number 
PHMSA-2021-0039 by any of the following methods:
    E-Gov Web: https://www.regulations.gov. This site allows the public 
to enter comments on any Federal Register notice issued by any agency. 
Follow the online instructions for submitting comments.
    Mail: Docket Management System: U.S. Department of Transportation, 
1200 New Jersey Avenue SE, West Building Ground Floor, Room W12-140, 
Washington, DC 20590-0001.
    Hand Delivery: U.S. DOT Docket Management System, West Building 
Ground Floor, Room W12-140, 1200 New Jersey Avenue SE, Washington, DC 
20590-0001 between 9 a.m. and 5 p.m., Monday through Friday, except 
Federal holidays.
    Fax: 1-202-493-2251.
    Instructions: Please include the docket number PHMSA-2021-0039 at 
the beginning of your comments. If you submit your comments by mail, 
submit two copies. If you wish to receive confirmation that PHMSA has 
received your comments, include a self-addressed stamped postcard. 
Internet users may submit comments at https://www.regulations.gov/.
    Note: Comments are posted without changes or edits to https://www.regulations.gov, including any personal information provided. There 
is a privacy statement published on https://www.regulations.gov.
    Privacy Act: In accordance with 5 U.S.C. 553(c), DOT solicits 
comments from the public to better inform its rulemaking process. DOT 
posts these comments, without edit, including any personal information 
the commenter provides, to www.regulations.gov, as described in the 
system of records notice (DOT/ALL-14 FDMS), that can be reviewed at 
www.dot.gov/privacy.
    Confidential Business Information: Confidential Business 
Information (CBI) is commercial or financial information that is both 
customarily and actually treated as private by its owner. Under the 
Freedom of Information Act (FOIA, 5 U.S.C. 552), CBI is exempt from 
public disclosure. If your comments responsive to this document contain 
commercial or financial information that is customarily treated as 
private, that you actually treat as private, and that is relevant or 
responsive to this notice, it is important that you clearly designate 
the submitted comments as CBI. Pursuant to 49 CFR 190.343, you may ask 
PHMSA to give confidential treatment to information you give to the 
agency by taking the following steps: (1) mark each page of the 
original document submission containing CBI as ``Confidential''; (2) 
send PHMSA, along with the original document, a second copy of the 
original document with the CBI deleted; and (3) explain why the 
information you are submitting is CBI. Submissions containing CBI 
should be sent to Sayler Palabrica, Office of Pipeline Safety (PHP-30), 
Pipeline and Hazardous Materials Safety Administration (PHMSA), 2nd 
Floor, 1200 New Jersey Avenue SE, Washington, DC 20590-0001, or by 
email at [email protected]. Any commentary PHMSA receives that 
is not specifically designated as CBI will be placed in the public 
docket.
    Docket: For access to the docket to read background documents or 
comments received, go to http://www.regulations.gov. Follow the online 
instructions for accessing the docket. Alternatively, you may review 
the documents in person at the street address listed above.

FOR FURTHER INFORMATION CONTACT: Sayler Palabrica, Transportation 
Specialist, by telephone at 202-744-0825 or by email at 
[email protected].

SUPPLEMENTARY INFORMATION:
I. Executive Summary
    A. Purpose of Regulatory Action
    B. Summary of the Major Regulatory Provisions
    C. Costs and Benefits
II. Background
    A. The Urgency of Methane Emissions Reductions in Confronting 
the Climate Crisis
    B. Dimensions of the Climate Crisis
    C. Methane Emissions From Gas Pipeline Facilities
    D. The Need for Updating PHMSA Regulations To Incorporate 
Advanced Leak Detection Programs To Reduce Unintentional Releases 
From Gas Pipelines
    E. The Limits of PHMSA Regulation and State and Operator 
Initiatives in Reducing Intentional Methane Releases From Gas 
Pipeline Facilities
III. Federal Efforts To Address Climate Change by Reducing Methane 
Emissions
    A. The PIPES Act of 2020
    B. Administration Efforts Confronting the Climate Crisis
    C. PHMSA Implementation of the PIPES Act of 2020
IV. Summary of Proposals
    A. Leakage Survey and Patrol Frequencies and Methodologies
    B. Advanced Leak Detection Programs
    C. Leak Grading and Repair
    D. Qualification of Leakage Survey, Investigation, and Repair 
Personnel
    E. Reporting and National Pipeline Mapping System
    F. Mitigating Vented and Emissions From Gas Pipeline Facilities
    G. Design, Configuration, and Maintenance of Pressure Relief 
Devices
    H. Investigation of Failures
    I. Type B and Type C Gathering Pipelines
    J. Miscellaneous Changes in Parts 191 and 192 to Reflect 
Codification in Federal Regulation of the Congressional Mandate To 
Address Environmental Hazards of Leaks From Gas Pipelines
V. Section-by-Section Analysis
VI. Regulatory Analyses and Notices

I. Executive Summary

A. Purpose of Regulatory Action

    This notice of proposed rulemaking (NPRM) proposes a series of 
regulatory

[[Page 31891]]

amendments to the Federal pipeline safety regulations (49 CFR parts 190 
through 199) in response to a bipartisan congressional mandate in the 
Protecting our Infrastructure of Pipelines and Enhancing Safety Act of 
2020 (PIPES Act of 2020, Pub. L. 116-260) and in support of the Biden-
Harris Administration's U.S. Methane Emissions Reduction Action Plan. 
The amendments would reduce both ``fugitive emissions'' (meaning 
unintentional emissions resulting from leaks and equipment failures) 
and ``vented emissions'' (meaning those emissions resulting from 
blowdowns, equipment design features, and other intentional releases, 
also called ``intentional emissions'') from over 2.7 million miles of 
gas transmission, distribution, and gathering pipelines and other gas 
pipeline facilities as well as 403 underground natural gas storage 
facilities (UNGSFs) and 165 liquefied natural gas (LNG) facilities, 
thereby improving public safety, promoting environmental justice, and 
addressing the climate crisis.
    The Federal pipeline safety regulations currently covering leak 
detection and repair reflect a regulatory approach focused on public 
safety risks posed by incidents on gas pipeline facilities. The 
regulations do not sufficiently capture environmental costs, align with 
the importance attached to environmental protection in PHMSA's enabling 
statutes,\1\ or reflect the scientific consensus that prompt reductions 
in methane emissions from natural gas infrastructure are critical to 
limiting the impacts of climate change. This current approach also 
foregoes opportunities to ensure timely identification and repair of 
leaks that can degrade into catastrophic failures and incidents 
threatening to public safety. The Federal leak detection and repair 
standards for gas pipelines have remained largely unchanged since the 
1970s despite significant improvements in leak detection technology and 
operator practices and the increasingly urgent and tangible threats 
from climate change. The current pipeline safety regulations do not 
include any meaningful performance standards for leak detection 
equipment, nor requirements that leverage the significant advancements 
in the sensitivity, efficiency, and variety of leak detection 
technologies in the last five decades. Further, the current pipeline 
safety regulations do not explicitly require repair of all--or even 
most--leaks on gas pipeline facilities. Leaks that an operator 
determines do not to present an existing or probable public safety 
hazard do not need to be repaired at all regardless of the resulting 
environmental harms posed by that release. Current regulations also do 
not prescribe specific timeframes for the timely repair of hazardous or 
any other leaks, other than leaks associated with certain metal loss, 
cracking, and denting defects that are discovered on gas transmission 
piping during an integrity assessment in accordance with gas 
transmission integrity management in subpart O of 49 CFR part 192 or 
Sec.  192.714. Additionally, despite a new self-executing section of 
the PIPES Act of 2020, described below, current regulations tolerate 
significant intentional emissions of methane and other gases, even in 
non-emergency situations, by allowing venting, blowdowns, and other 
large-volume releases of gas from all PHMSA-jurisdictional pipeline 
facilities without restriction. Consistent with the pipeline safety 
regulations' historical lack of emphasis on the environmental 
consequences of gas releases, PHMSA's minimum incident reporting 
threshold was established principally to better reflect the economic 
consequence of lost gas \2\ and was set at 3 million standard cubic 
feet (MMCF), which leaves many large-volume gas releases unreported. 
And PHMSA has no reporting requirements for intentional releases of gas 
at all.
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    \1\ 49 U.S.C. 60102(b)(1)(B)(ii), 60102(b)(2)(A)(iii), 
60102(b)(5), 60102(q)(1)(B), 60102(q)(2)(B)(i).
    \2\ Prior to the adoption of the volumetric incident criterion, 
the cost of lost gas was included in the property damage 
calculation. In the NPRM that proposed the adoption of a volumetric 
threshold, PHMSA described both a petition from the Interstate 
Natural Gas Association of America noting that more incidents were 
reportable due to changes in the cost of gas, as well as a GAO 
recommendation (GAO-06-946) to adjust the incident reporting 
criteria to account for the cost of lost gas. That NPRM did not 
identify environmental considerations among the motivations for that 
change in incident reporting requirements. See 74 FR 31675, 31677 
(July 2, 2009).
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    Congress targeted these regulatory shortcomings in the bipartisan 
PIPES Act of 2020. Section 113 mandated that PHMSA establish 
performance standards for leak detection and repair programs for 
certain part 192-regulated \3\ gas gathering, transmission, and 
distribution operators reflecting commercially available advanced 
technology and practices for the identification, location, 
categorization, and repair of all leaks that are hazardous to public 
safety or the environment. Section 114 of the PIPES Act of 2020, 
moreover, requires operators of all pipeline facilities with 
maintenance and inspection procedures to update pertinent manuals to 
address the elimination of hazardous leaks and minimize releases of 
natural gas--whether fugitive emissions from leaks or intentional 
releases due to venting from maintenance and other activities--and 
repair or remediate pipelines known to leak. And section 118 of the 
PIPES Act of 2020 clarified that PHMSA must consider environmental 
benefits equally with public safety benefits. The mandates in the PIPES 
Act of 2020 align with the importance of addressing climate change by 
reducing methane emissions.
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    \3\ Throughout this NPRM, PHMSA uses the phrase ``part 192-
regulated gas gathering pipelines'' to refer to offshore gas 
gathering pipelines, as well as Types A, B, and C ``regulated 
onshore gas gathering'' pipelines--all of which are subject to 
certain part 192 requirements under Sec. Sec.  192.8 and 192.9. Such 
``part 192-regulated gas gathering pipelines'' does not include 
``reporting-regulated'' or ``Type R'' gas gathering pipelines as 
defined in Sec. Sec.  191.3 and 192.8(c)(3), which are not subject 
to part 192 safety requirements. Similarly, PHMSA also refers to 
``part 192-regulated gas pipelines'' to collectively refer to gas 
transmission, distribution, offshore gathering, and Types A, B, and 
C onshore gathering pipelines subject to part 192 requirements. 
``Gas pipeline facilities'' is defined as ``a pipeline, a right of 
way, a facility, a building, or equipment used in transporting gas 
or treating gas during its transportation''--this broader definition 
applies to all part 192-regulated gas pipelines, UNGSFs, and part 
193-regulated LNG facilities. See 49 U.S.C. 60101(a)(3).
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    PHMSA proposes a number of regulatory revisions to minimize 
emissions of methane and other (flammable, toxic, or corrosive) gases 
from, and improve public safety of, new and existing offshore gas 
gathering, regulated onshore gas gathering, transmission and 
distribution pipelines, UNGSFs and LNG facilities. PHMSA expects that 
the proposed regulatory amendments would yield prompt and meaningful 
reduction of methane emissions, a key contributor to climate change; 
improve public safety; and mitigate the disproportionate burden of 
those environmental and safety risks historically placed on minority, 
low-income, or other underserved and disadvantaged populations and 
communities.

B. Summary of the Regulatory Provisions

    This NPRM contains the following proposed changes to the 
regulations: (1) strengthen leakage survey and patrolling requirements 
at Sec. Sec.  192.9, 192.705, 192.706, 192.723 for all part 192-
regulated gas pipelines, as well as introduce periodic methane leakage 
survey requirements for part 193-regulated LNG facilities; (2) 
introduce for all part 192-regulated gas pipelines an Advanced Leak 
Detection Program (ALDP) performance standard at a new Sec.  192.763 
reflecting the capabilities of

[[Page 31892]]

commercially available advanced technologies and practices; (3) amend 
Sec.  192.703 to require operators of all part 192-regulated gas 
pipelines to grade and repair all leaks, and not merely those that pose 
public safety risks; (4) establish for all part 192-regulated gas 
pipelines minimum criteria for leak grades and associated repair 
schedules prioritized by safety and environmental hazard at a new Sec.  
192.760; (5) require reductions in intentional sources of methane 
emissions by minimizing releases associated with blowdowns and other 
vented emissions from gas transmission, offshore gas gathering, and 
Type A gas gathering pipelines (at Sec.  192.770) and LNG facilities 
(at Sec.  193.2523); (6) require operators of certain part 192-
regulated gas pipelines to reduce emissions associated with the design, 
configuration, and maintenance of pressure relief devices (Sec. Sec.  
192.199 and 192.773); (7) codify in Federal regulations a congressional 
requirement for operators of gas pipeline facilities to implement 
written procedures to eliminate hazardous leaks, minimize releases of 
natural gas, and remediate or replace pipelines known to leak 
(Sec. Sec.  192.9, 192.12, 192.605, 193.2503, and 193.2605); (8) expand 
reporting requirements (at Sec. Sec.  191.3 and 191.19) and 
recordkeeping requirements (at Sec. Sec.  192.760 and 192.773) to 
provide higher-quality information on unintentional and intentional gas 
releases from gas pipeline facilities; (9) require that Types A, B, and 
C gathering pipeline operators submit geospatial pipeline location data 
to the National Pipeline Mapping System (NPMS) pursuant to Sec.  
191.29; (10) incorporate explicit reference to environmental harm among 
the ``hazards'' addressed in certain parts 191 and 192 requirements; 
and (11) introduce, for certain components and equipment within part 
193-regulated LNG facilities, at a new Sec.  193.2624, requirements for 
periodic methane leakage surveys using leak detection equipment and 
repair of identified leaks pursuant to operators' written maintenance 
or abnormal operations procedures. PHMSA proposes an effective date for 
this rulemaking of 6 months following publication of a final rule in 
the Federal Register. The eleven proposed requirements are described in 
the paragraphs immediately below, and further detail is provided in 
sections IV and V.
    First, PHMSA proposes increased leakage survey frequencies for 
distribution pipelines outside of business districts,\4\ annual leakage 
surveys for distribution pipelines that lack cathodic protection or 
which are known to leak based on their material (cast-iron, 
cathodically unprotected steel, wrought-iron, and certain plastic 
pipelines), design, or operational and maintenance history; and for gas 
transmission, offshore gathering, and Types A, B, and C gathering 
pipelines in high consequence areas (HCAs), with the most frequent 
leakage surveys to be performed on gas transmission and Types A and B 
gathering pipelines located in HCAs within Class 4 locations. PHMSA 
also proposes to increase minimum patrolling frequencies for gas 
transmission, offshore gathering, and Type A gathering pipelines and to 
introduce requirements for annual patrolling of Type B and Type C 
gathering pipelines. Finally, PHMSA proposes to establish methane 
leakage survey requirements for LNG facilities other than tanks.
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    \4\ The term ``business district'' is not defined in part 192. 
However, in a letter of interpretation PHMSA stated that the term 
normally refers to an area ``associated with the assembly of people 
in shops, offices and the like,'' marked by the conduct of ``buying 
and selling commodities and services, and related transactions.'' 
See PHMSA, Interpretation Response Letter No. PI-72-038 (Aug. 16, 
1972).
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    Second, PHMSA proposes to introduce an ALDP performance standard 
that would require operators of part 192-regulated gas pipelines to 
demonstrate, by conducting engineering tests and analyses, that their 
suite of leak detection equipment, procedures, and analytics are 
capable of detecting all leaks above a minimum concentration threshold 
when measured in close proximity to the pipeline. PHMSA proposes to 
require that leakage surveys be performed using commercially available 
advanced technology and practices consistent with the proposed ALDP 
performance standard. PHMSA also proposes to require a minimum 
sensitivity for leak detection equipment used in leakage surveys and 
leak investigations. PHMSA proposes to limit the use of human or animal 
senses for leakage surveys to offshore, submerged gas transmission and 
gathering pipelines. Human senses may also be used for gas transmission 
and regulated gas gathering lines in Class 1 and Class 2 locations 
outside of HCAs, but only with prior notification to and no objection 
from PHMSA in accordance with Sec.  192.18.
    Third, PHMSA proposes to require operators of gas transmission, 
distribution, and part 192-regulated gathering pipelines to identify, 
locate, classify, and repair in a timely manner all leaks. Part 192 
provisions governing the repair of leaks are narrowly focused on public 
safety risks associated with ignition of large-volume, instantaneous 
releases and accumulated gas; they are unclear regarding when, if at 
all, most leaks must be repaired. Although some--not all--part 192-
regulated pipelines are subject to a general maintenance requirement in 
Sec.  192.703(c) to ``promptly repair hazardous leaks,'' part 192 
maintenance requirements neither define ``hazardous leak'' in terms of 
risks to the environment nor establish meaningful timelines for repair 
of hazardous or any other leaks. These proposed amendments would 
address the section 113 mandate of the PIPES Act of 2020 requiring 
identification, location, classification, and repair of leaks hazardous 
to either public safety or the environment.
    Fourth, this NPRM proposes that operators of gas transmission, 
distribution, and part 192-regulated gathering pipelines must classify 
and repair all identified leaks on a schedule that depends on the 
severity of public safety and environmental risks. PHMSA's proposed 
requirements build on the tiered framework of the Gas Piping Technology 
Committee (GPTC) ``Guide for Gas Transmission and Distribution Piping 
Systems'' \5\ leak grading and repair criteria. PHMSA's proposed 
framework would require the classification of every leak (as either 
grade 1, grade 2, or grade 3) and to prioritize remediation of leaks 
posing the most significant risks to public safety or the environment.
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    \5\ Gas Piping Technology Committee Z380, ANSI GPTC Z380.1-2022, 
``The Guide for Gas Transmission, Distribution, and Gathering Piping 
Systems'' Including Addenda 1 and 2 (2022).
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    Fifth, PHMSA proposes requirements for the mitigation of 
intentional emissions such as blowdowns on gas transmission, offshore 
gas gathering, and Type A gas gathering pipelines and LNG facilities. 
This proposal requires an operator to choose from among prescribed, 
proven, cost-effective mitigation measures when performing blowdowns 
related to operations, maintenance, or construction.
    Sixth, PHMSA proposes requirements for operators of gas 
transmission, distribution, offshore gathering, and Types A, B, and C 
gathering pipelines to design and configure all new and modified 
pressure relief and limiting devices to minimize unnecessary releases 
and to assess and remediate any relief devices that operate outside of 
the tolerances established in the operator's procedures. These proposed

[[Page 31893]]

requirements would minimize unintended and unnecessary releases of gas 
to the atmosphere, better protecting against environmental and public 
safety hazards posed by malfunctioning or poorly designed and 
configured pressure relief devices.
    Seventh, PHMSA proposes to codify in regulation self-executing 
requirements from section 114 of the PIPES Act of 2020, which obliges 
operators of gas pipeline facilities to have written procedures that 
address the elimination of hazardous leaks, minimize releases of 
natural gas, and provide for repair or replacement of pipelines known 
to leak based on material, design, or past operating and maintenance 
histories. These changes would support PHMSA's cooperation with states 
undertaking inspection and enforcement activity in connection with 
those requirements.
    Eighth, this NPRM proposes a series of changes to part 191 
reporting requirements. PHMSA proposes to introduce requirements for 
reporting large-volume releases of gas from all gas pipeline 
facilities, including intentional releases, that are not currently 
captured by the definition of an incident in part 191. Specifically, 
this NPRM proposes to create a report for both unintentional releases 
and, for the first time, intentional releases of 1 MMCF or more of gas 
from any gas pipeline facility. PHMSA also proposes revisions to annual 
reporting requirements for gas transmission, distribution, offshore 
gathering, and Types A, B, and C gathering pipelines to convey 
information regarding the number and grade of all leaks detected and 
repaired each calendar year as well as estimated emissions from those 
leaks.
    Ninth, this NPRM further proposes to extend NPMS reporting 
requirements at Sec.  191.29 to offshore gas gathering pipelines as 
well as Types A, B, and C onshore gas gathering pipelines.
    Tenth, this NPRM proposes incorporation of explicit reference to 
environmental harm among the ``hazards'' addressed in certain part 191 
and 192 requirements, consistent with section 118 of the PIPES Act of 
2020. PHMSA's proposed expansion of the concept of ``hazards'' to 
encompass environmental harms would not extend to integrity management 
(IM) regulations in part 192, subparts O (gas distribution pipelines) 
and P (gas transmission pipelines), which would remain focused on 
safety, and certain other existing requirements directed at hazards to 
public safety in particular (described in detail in section IV.J).
    Finally, this NPRM proposes a new Sec.  193.2624 that would oblige 
operators of part 193-regulated LNG facilities to perform quarterly 
methane leakage surveys of non-tank equipment and components within an 
LNG facility using leak detection equipment satisfying the minimum 5 
parts per million (ppm) sensitivity proposed elsewhere within this 
NPRM. Operators would also need to repair any leaks identified in a 
manner and on a schedule consistent with their maintenance or abnormal 
operations procedures. PHMSA also proposes conforming changes to annual 
report forms for LNG facilities to ensure meaningful reporting of 
methane leaks discovered and repaired pursuant to the proposed Sec.  
193.2624.

C. Costs and Benefits

    Consistent with Executive Order (E.O.) 12866 and the requirements 
of the Federal Pipeline Safety Laws,\6\ PHMSA has prepared an 
assessment of the benefits and costs (to include pertinent commercial 
benefits, public safety benefits, environmental benefits, equity 
benefits, compliance costs, and other risks) of this proposed rule, as 
well as reasonable alternatives. PHMSA estimates that emission 
reductions under the proposed rule correspond to approximately 72 
percent of unintentional emissions from regulated gathering pipelines, 
17 percent of unintentional emissions from transmission pipelines, and 
44 to 62 percent of unintentional emissions from distribution 
pipelines. These shares are relative to modeled baseline emissions 
projected over the period of analysis based on the pipeline mileage, 
empirical emission factors, and existing survey and repair practices. 
Further, PHMSA estimates that the total avoided blowdown emissions 
under the proposed rule correspond to approximately 43 percent of 
baseline blowdown emissions. PHMSA estimates that the proposed rule 
would result in monetized net benefits between $341 to $1,440 million 
per year using a 3 percent discount rate. PHMSA also anticipates 
additional unquantified benefits to public safety and the environment, 
each discussed throughout this NPRM and its supporting documents 
(including the Preliminary Regulatory Impact Analysis (RIA) and draft 
Environmental Assessment (EA), each available in the docket for this 
NPRM).
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    \6\ 49 U.S.C. 60101 et seq. (Federal Pipeline Safety Laws). The 
specific provision referenced in the above discussion is 49 U.S.C. 
60102(b)(5).
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    The regulatory amendments proposed in this NPRM are expected to 
improve public safety, reduce threats to the environment (including, 
but not limited to, reduction of methane emissions contributing to the 
climate crisis), and promote environmental justice for minority 
populations, low-income populations, and other underserved and 
disadvantaged communities. Additionally, reducing product losses 
results in cost savings for natural gas shippers and consumers and 
improves the efficiency and reliability of U.S. energy infrastructure. 
PHMSA expects that each of the elements of this rulemaking as proposed 
in this NPRM would be technically feasible, reasonable, cost-effective, 
and practicable because of the public safety, environmental, and equity 
benefits of the proposed regulatory amendments described in this NPRM 
and its supporting documents (including the Preliminary RIA and draft 
EA) which justify any associated costs. PHMSA has preliminarily 
determined that the proposed rule is superior to alternatives 
considered in the Preliminary RIA.

II. Background

A. The Urgency of Methane Emissions Reductions in Confronting the 
Climate Crisis

    The primary component of natural gas is methane (CH4). 
Methane is a greenhouse gas, or GHG, which means that its concentration 
in the atmosphere affects the climate and temperature of the Earth by 
trapping heat in the atmosphere. Methane is released from both natural 
and anthropogenic sources, the latter of which includes leaks and other 
releases from natural gas pipeline systems. Methane is the second most 
abundant anthropogenic GHG in the Earth's atmosphere, after carbon 
dioxide (CO2), by concentration and accounts for the second-
greatest contribution to total radiative forcing (warming effect).\7\ 
The Environmental Protection Agency (EPA) calculated that methane made 
up approximately 11 percent (by mass of CO2 equivalents) of 
the annual GHG emissions in 2019 within the United States, whereas 
carbon dioxide made up 79 percent of the total GHG emissions over the 
same period.\8\ According to the 2021 installment of the Sixth 
Assessment Report (2021 IPCC Report) from Working Group I of the 
Intergovernmental Panel on Climate Change (IPCC), the atmospheric 
concentration of methane gas was

[[Page 31894]]

measured at 1,866 parts per billion (ppb), compared with 410 ppm of 
carbon dioxide.\9\
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    \7\ National Oceanic and Atmospheric Administration (NOAA), 
``Annual Greenhouse Gas Index'' at Figure 3 & Table 2 (Spring 2022), 
https://gml.noaa.gov/aggi/aggi.html.
    \8\ EPA, ``Overview of Greenhouse Gases,'' https://www.epa.gov/ghgemissions/overview-greenhouse-gases#methane (last accessed 
December 5, 2022).
    \9\ IPCC, Climate Change 2021: The Physical Science Basis. 
Contribution of Working Group I to the Sixth Assessment Report of 
the Intergovernmental Panel on Climate Change, Summary for 
Policymakers (SPM)-5 (2021). In the 2021 IPCC Report, atmospheric 
concentration of CH4 since 1984 (1980 for CO2) 
is based on merging observed gas concentration in the lower 
troposphere from the NOAA Global Monitoring Laboratory and the 
Advanced Global Atmospheric Gases Experiment monitoring networks. 
Emissions in 1850 and earlier are estimated based on assessments of 
multiple ice cores. 2021 IPCC Report, Table 2.2 and Table AIII.1a.
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    However, this comparatively small concentration of methane in the 
atmosphere makes an outsized contribution to climate change. The 2021 
IPCC Report notes that anthropogenic methane emissions account for 
approximately one-third of warming of global average surface 
temperatures attributed to well-mixed GHG \10\ emissions since 
1850.\11\ The IPCC also noted that in 2019, atmospheric CH4 
concentrations were higher than at any time in 800,000 years, and that 
``strong, rapid and sustained reductions in CH4 emissions'' 
would be needed to offset short-term warming effects.\12\
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    \10\ According to the IPCC, well-mixed GHGs include 
CO2, N2O, and CH4. 2021 IPCC 
Report, 2.2. These gases ``generally have lifetimes of more than 
several years'' and therefore are relatively uniformly distributed 
within the troposphere (lower-atmosphere). 2021 IPCC Report, 2.2.3.
    \11\ 2021 IPCC Report, SPM-8.
    \12\ 2021 IPCC Report, SPM-9, SPM-36.
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    Once emitted into the atmosphere, some GHGs can persist in the 
atmosphere for a long time. Carbon dioxide, for instance, remains in 
the atmosphere for 300 to 1000 years.\13\ Methane, on the other hand, 
is more short-lived than CO2 but is much more potent in 
trapping heat in the atmosphere. Methane only lasts in the atmosphere 
for approximately 12 years once released; however, it traps 
approximately 25 times more energy than an equal mass of carbon dioxide 
over a 100-year period.\14\ Because methane is a more potent, but more 
short-lived, GHG compared to carbon dioxide, reducing methane emissions 
would have a more rapid and significant effect on reducing heat-
trapping potential of the atmosphere than an equivalent reduction in 
carbon dioxide and would therefore result in a greater effect on 
climate change mitigation in the short term.\15\
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    \13\ Buis, ``The Atmosphere: Getting a Handle on Carbon 
Dioxide'' (Oct. 9, 2019).
    \14\ EPA, ``Overview of Greenhouse Gases,'' https://www.epa.gov/ghgemissions/overview-greenhouse-gases (last accessed July 20, 
2022).
    \15\ EPA, ``Importance of Methane,'' https://www.epa.gov/gmi/importance-methane (last accessed July 20, 2022).
---------------------------------------------------------------------------

    Authoritative scientific projections underscore the need for 
achieving a prompt reduction in methane emissions. The 2021 IPCC Report 
concluded that urgent action to reduce emissions across all GHG 
categories is necessary to minimize global warming and avoid the most 
destructive effects of climate change.\16\ The report details five 
possible future emissions and warming scenarios: two high emissions 
scenarios (SSP3-7.0 and SSP5-8.5), an intermediate scenario with 
emissions similar to the status quo through mid-century (SSP2-4.5), and 
two relatively low-emissions scenarios (SSP1-1.9 and SSP1-2.6). Of 
these, only the two low-emissions scenarios are likely to hold 
temperature increases below the Paris Agreement's target of limiting 
the increase in global average surface temperature to 2.0 [deg]C above 
1850 levels by the end of the century,\17\ and only the very low-
emissions scenario (SSP1-1.9) is likely to limit warming to 1.5 [deg]C 
by the end of the century (specifically, between 1.0 [deg] to 1.8 
[deg]C above 1850 levels, consistent with the Paris Agreement). Both of 
those low-emissions scenarios require cutting methane emissions by 
approximately half of 2015 levels before 2050.\18\ Rapid and full-scale 
efforts to reduce methane and other GHG emissions are needed to achieve 
the very low-emissions scenario (SSP1-1.9).\19\ In contrast, the 
intermediate scenario (SSP2-4.5) results in potentially dangerous 
warming of 2.0 [deg]C by midcentury, rising to between 2.1 [deg] to 3.5 
[deg]C by 2100.
---------------------------------------------------------------------------

    \16\ PHMSA acknowledges much of the discussion in section II and 
elsewhere in this NPRM is focused on methane emissions from natural 
gas pipeline facilities, as those facilities constitute the great 
majority of gas pipeline facilities subject to parts 191 and 192. 
However, PHMSA parts 191 and 192 requirements are not limited to 
natural gas pipelines; rather, they also apply to pipeline 
facilities transporting other gases which are flammable, toxic, or 
corrosive--releases of which may entail significant public safety or 
environmental consequences (including potential contributions to 
climate change) in their own right. See Sec. Sec.  191.3 and 192.3 
(definitions of ``gas'' for the purposes of parts 191 and 192, 
respectively).
    \17\ 2021 IPCC Report, 1.2.
    \18\ 2021 IPCC Report, SPM-16, Table SPM.1.
    \19\ 2021 IPCC Report, Table SPM.1.
---------------------------------------------------------------------------

B. Dimensions of the Climate Crisis

    Near-term methane emissions reductions are especially compelling 
because global climate change is already causing observable, damaging 
effects on the environment. The 2021 IPCC Report shows that the 
environmental and social consequences of climate change are no longer 
abstract, distant problems: scientists note increased surface 
temperature, extreme weather events, rising sea levels, and other 
consequences are being felt today and predict those effects will 
intensify in the coming decades without immediate action to control GHG 
emissions to avoid or stave off the worst effects of climate change. 
Higher average surface temperatures will result in sea level rise, 
severe heat waves, and more intense extreme weather events (hurricanes, 
storms, droughts, and floods), in turn altering water supplies, 
damaging habitats, and promoting wildfires. According to the findings 
from the 3rd and 4th National Climate Assessment Reports released by 
the U.S. Global Change Research Program,\20\ these dimensions of 
climate change will have severe consequences for the human population 
throughout the United States including alteration of population 
distributions; widespread property damage; compromised local economies; 
disrupted agriculture, fisheries, and other ecosystems; and degraded 
public health.
---------------------------------------------------------------------------

    \20\ See U.S. Global Change Research Program, Climate Science 
Special Report: Fourth National Climate Assessment, Volume I (2017); 
U.S. Global Change Research Program, Climate Change Impacts in the 
United States: The Third National Climate Assessment (2014).
---------------------------------------------------------------------------

    The most immediate impact of climate change worldwide has been, and 
will continue to be, an increase in average surface temperatures. The 
average global surface temperature during 2021 was 1.51 degrees 
Fahrenheit (0.84 degrees Celsius) warmer than the average temperature 
in the 20th century (57.0 degrees Fahrenheit) and was 1.87 degrees 
Fahrenheit (1.04 degrees Celsius) warmer than the average temperature 
between 1880-1900, which NOAA describes as a ``reasonable surrogate for 
pre-industrial conditions.'' \21\ That observed surface temperature 
increase has resulted in cascading consequences for the natural world 
already; as more GHGs are added to the atmosphere, the rate of warming 
is expected to continue to accelerate.
---------------------------------------------------------------------------

    \21\ See NOAA National Centers for Environmental Information, 
Monthly Global Climate Report for Annual 2021 (Jan. 2022), https://www.ncei.noaa.gov/news/global-climate-202112.
---------------------------------------------------------------------------

    Increasing the average surface temperature of the Earth changes the 
frequency and intensity of extreme temperature events. Higher average 
surface temperatures means that heat waves everywhere will become more 
frequent and more intense.\22\ The IPCC estimates that current levels 
of warming

[[Page 31895]]

have made 10-year extreme heat events \23\ approximately 1.2 degrees 
Fahrenheit more intense and 2.8 times more frequent. Likewise, the IPCC 
estimates that 50-year extreme heat events have become 4.8 times more 
frequent. The estimated frequency and intensity of extreme heat events 
will increase further with additional warming, especially in warmer 
summer months.\24\
---------------------------------------------------------------------------

    \22\ 2021 IPCC Report, SPM-8, SPM-18.
    \23\ Defined by the IPCC as ``daily maximum temperatures over 
land that were exceeded on average once in a decade (10-year event) 
or once every 50 years (50-year event) during the 1850-1900 
reference period.'' See 2021 IPCC Report, SPM-24.
    \24\ 2021 IPCC Report, SPM-23.
---------------------------------------------------------------------------

    A well-known consequence of elevated (average and instantaneous) 
surface temperatures is rising sea levels. The global sea level has 
risen by about 5.9-9.8 inches (0.15-0.25 meters) between 1901 and 2018 
and the rate of increase and degree to which sea level rise can be 
attributed with confidence to anthropogenic climate change have both 
increased since 1971.\25\ The IPCC has determined that it is 
``virtually certain'' that the global sea level will rise further by 
2100, as land ice continues to melt and seawater expands as it warms, 
with greater sea level rise resulting from higher GHG emissions 
scenarios.\26\ An expected contributor to global sea level rise is the 
loss of virtually all summer ice from the Arctic Ocean before 2050.\27\ 
Global average sea levels are projected to rise an additional 1.0-4.3 
feet by 2100 under intermediate emissions scenarios, with a global sea 
level rise in excess of 8 feet possible by 2100 under higher emissions 
scenarios.\28\
---------------------------------------------------------------------------

    \25\ 2021 IPCC Report, SPM-6.
    \26\ 2021 IPCC Report, SPM-28.
    \27\ European Space Agency (ESA), ``Simulations Suggest Ice-Free 
Arctic Summers by 2050'' (May 13, 2020), https://climate.esa.int/en/projects/sea-ice/news-and-events/news/simulations-suggest-ice-free-arctic-summers-2050/.
    \28\ U.S. Global Change Research Program, Impacts, Risks, and 
Adaptation in the United States: Fourth National Climate Assessment, 
Volume II--Southeast at 758. (2018).
---------------------------------------------------------------------------

    Rising average surface temperatures also alter water cycles and 
weather patterns such as precipitation and hurricanes. As noted above, 
higher average and instantaneous surface temperatures will result in 
loss of soil moisture in most regions. Meanwhile, some areas are 
increasingly likely to experience heavy downpours, while other areas 
will likely receive far less precipitation than in years past.\29\ 
Areas that are projected to have less total precipitation and higher 
temperatures will likely become more susceptible to drought and 
wildfires as a result; as described below, the United States has 
already seen the acreage affected by wildfires trend upwards in recent 
decades. Scientists also project that the recent trend toward more 
frequent heavy precipitation events will continue, even in areas where 
the total precipitation is expected to decrease, which could lead to 
increased flooding risks, erosion, and land subsidence. As further 
noted below, earth and water movement are also threats to pipeline 
integrity that can lead to pipeline incidents and accidents that 
threaten public safety and the environment.\30\ Similarly, scientists 
have observed that it is likely that hurricanes have become stronger 
and more intense and determined that it is likely that anthropogenic 
climate change has increased rainfall rates associated with hurricanes 
and other tropical cyclones.\31\
---------------------------------------------------------------------------

    \29\ 2021 IPCC Report, SPM-15.
    \30\ PHMSA, ``Pipeline Safety: Potential for Damage to Pipeline 
Facilities Caused by Earth Movement and Other Geological Hazards,'' 
87 FR 33576 (June 2, 2019) (Advisory Bulletin ADB-2022-01).
    \31\ 2021 IPCC Report, SPM-9.
---------------------------------------------------------------------------

    The United States has a front-row seat to the effects of climate 
change. Already, many areas of the United States are seeing increases 
in the duration and frequency of heat waves and altered precipitation 
patterns. The 2021 IPCC Report describes observed increases in extreme 
heat and drought events occurring around the world, including western 
North America.\32\ The Colorado River in the Southwest United States is 
facing its first-ever water shortage, a phenomenon that is directly 
linked to warming temperatures. Due to this historic shortage, in 2022, 
the U.S. Department of the Interior`s Bureau of Reclamation proposed 
significant cuts to water allocations from the Colorado River to 
Arizona, Nevada, and Mexico in order to ensure continued operation of 
hydroelectric generation facilities.\33\ In late June and early July of 
2021, the Western part of the United States and Canada suffered a heat 
wave that was likely exacerbated by climate change, with consequences 
ranging as far north as the Yukon territory in Canada, and as far 
inland as the State of Montana. Much of the Pacific Northwest reached 
temperatures that were 20 to 35 degrees Fahrenheit above normal during 
this heat wave, with several daily high temperature records being 
broken. Temperatures grew so hot that nighttime low temperatures in 
many areas were higher than historical average daytime high 
temperatures.
---------------------------------------------------------------------------

    \32\ 2021 IPCC Report, SPM-12.
    \33\ Yanchin, ``Interior Threatens Colorado River Cuts,'' E&E 
News (Oct. 28, 2022), https://www.eenews.net/articles/interior-threatens-colorado-river-cuts/.
---------------------------------------------------------------------------

    Higher average surface temperatures and extreme instantaneous 
temperatures have also exacerbated wildfires in the United States. 
Prolonged heat has led to dry vegetation, and the heat and dry 
vegetation have contributed to the severity of several wildfires. 
According to the research compiled in the 4th National Climate 
Assessment, drought in California and the Colorado River Basin have 
made forests ``more susceptible to burning'' and caused ``spring-like 
temperatures to occur earlier in the year,'' extending the western fire 
season \34\ and doubling the cumulative forest area burned by wildfires 
between 1984 and 2015.\35\ Wildfires pose serious health risks, 
including illnesses from smoke inhalation and contaminated drinking 
water, and cause significant property damage ($3.1 billion in the Los 
Angeles area alone from 1990 to 2009, or approximately $4 billion in 
2021 dollars).\36\ The 4th National Climate Assessment cautions that 
the frequency and intensity of wildfires in the Western United States 
will increase with further warming, with higher emissions scenarios 
estimating a 25% increase in wildfires in the Southwest region and 
three times as many wildfires that exceed 5,000 hectares in size.\37\ 
Researchers at the University of California, Los Angeles and Columbia 
University have determined that the 22-year period from 2000-2021 was 
the driest such period in the Southwestern United States since the year 
800, due in large part to climate change.\38\ Climate change poses a 
significant threat of extending the drought even further. In fact, the 
Southwestern drought is expected to persist through at least the end of 
2022 and become the longest megadrought on record in the Southwestern 
United States, further endangering sources of water, and the

[[Page 31896]]

communities that rely on them, throughout the region.\39\
---------------------------------------------------------------------------

    \34\ U.S. Global Change Research Program, Impacts, Risks, and 
Adaptation in the United States: Fourth National Climate Assessment, 
Volume II--Southwest at 1115, 1116 (2018).
    \35\ U.S. Global Change Research Program, Impacts, Risks, and 
Adaptation in the United States: Fourth National Climate Assessment, 
Volume II--Southwest at 1115, 1135 & Figure 25.4 (2018).
    \36\ U.S. Global Change Research Program, Impacts, Risks, and 
Adaptation in the United States: Fourth National Climate Assessment, 
Volume II--Southwest at 1116 (2018); Inflation adjustment via 
Consumer Price Index inflation from December 2009 to December 2021.
    \37\ U.S. Global Change Research Program, Impacts, Risks, and 
Adaptation in the United States: Fourth National Climate Assessment, 
Volume II--Southwest at 1116 (2018).
    \38\ Williams et al., ``Rapid Intensification of the Emerging 
Southwestern North American Megadrought in 2020-2021,'' 12 Nature 
Climate Change (Mar. 1, 2022).
    \39\ Williams et al., ``Rapid Intensification of the Emerging 
Southwestern North American Megadrought in 2020-2021,'' 12 Nature 
Climate Change (Mar. 1, 2022).
---------------------------------------------------------------------------

    The United States will also experience dramatically altered 
precipitation and weather patterns from climate change. Increases in 
GHG concentrations in the atmosphere have already led to increased 
Atlantic hurricane activity, and a warming climate is projected to 
cause extreme rainfall and significant regional flooding from 
hurricanes, nor'easters, and other severe storms, in addition to 
exacerbating the intensity of hurricanes in the Atlantic and eastern 
North Pacific.\40\ While projections are difficult to make for 
infrequent, smaller weather events like tornadoes and severe 
thunderstorms, these events have also been recently exhibiting changes 
that may be caused by climate change.\41\ Moreover, tornadoes can be 
generated by hurricanes (such as the 25 tornadoes produced by Hurricane 
Irma in 2017, mostly along the east coast of Florida), and more intense 
hurricanes could generate more tornadoes.
---------------------------------------------------------------------------

    \40\ U.S. Global Change Research Program, Impacts, Risks, and 
Adaptation in the United States: Fourth National Climate Assessment, 
Volume II--Our Changing Climate at 74, 95 (2018) (noting the 
heaviest rainfall amounts from recent storms have been estimated to 
be 6-7% greater than the most intense storms of the early 1900s).
    \41\ U.S. Global Change Research Program, Impacts, Risks, and 
Adaptation in the United States: Fourth National Climate Assessment, 
Volume II--Our Changing Climate at 97 (2018).
---------------------------------------------------------------------------

    Climate change-induced sea level rise is and will continue to be 
experienced in the United States. Sea level rise has already led to 
more frequent high tide flooding. One study of flooding in 27 
communities cited in the Fourth National Climate Assessment found that 
the frequency of high tide flooding in several communities has 
increased by a factor of 5 or more, and that such flooding increased by 
a factor of 10 or more in Atlantic City (NJ), Baltimore (MD), Annapolis 
(MD), Wilmington (DE), Port Isabel (TX), and Honolulu (HI).\42\ In the 
Southeast, tidal data from the National Oceanic and Atmospheric 
Administration shows sea level rise of 1-3 feet has already occurred 
over the past 100 years. The effects of sea level rise are not 
distributed equally across the world, nor along the U.S. coastline; 
instead, the Northeast United States, eastern coast of Florida, and 
western Gulf Coast regions will likely experience the worst impacts 
from rising sea levels and coastal flooding due to ocean circulation, 
land subsidence, and uneven ice melt. The 4th National Climate 
Assessment identifies an average of 2 to 4.5 feet as the most probable 
sea level rise in the Northeast United States before 2100 with worst-
case estimates projecting sea level rise of more than 11 feet over the 
same period.\43\ Under higher emission projections, the 4th National 
Climate Assessment found it likely that all U.S. coastlines, other than 
Alaska, will experience sea level rise greater than the global averages 
due to Antarctic ice loss. By 2100, sea level rise is likely to 
submerge real estate worth between $238-507 billion across the United 
States and force the migration of substantial elements of the U.S. 
population.\44\ Average sea level rise of 6 feet by 2100 could displace 
an estimated 13.1 million people along the U.S. coasts.\45\
---------------------------------------------------------------------------

    \42\ Sweet & Park, ``From the Extreme to the Mean: Acceleration 
and Tipping Points of Coastal Inundation from Sea Level Rise, 
Earth's Future 2 at 579-600 (2014).
    \43\ U.S. Global Change Research Program, Impacts, Risks, and 
Adaptation in the United States: Fourth National Climate Assessment, 
Volume II--Northeast at 692 (2018).
    \44\ U.S. Global Change Research Program, Impacts, Risks, and 
Adaptation in the United States: Fourth National Climate Assessment, 
Volume II--Coastal Effects at 330, 335 (2018).
    \45\ U.S. Global Change Research Program, Impacts, Risks, and 
Adaptation in the United States: Fourth National Climate Assessment, 
Volume II--Coastal Effects at 335 (2018).
---------------------------------------------------------------------------

    These and other dimensions of the climate crisis also have 
disastrous near and long-term consequences for human health. The EPA 
Administrator, as early as 2009 \46\ (and again in 2016),\47\ 
determined that methane along with 5 other ``well-mixed greenhouse 
gases'' together constituted a harmful air pollutant that endangered 
public health and welfare of persons. According to the 2016 assessment 
of human health impacts of climate change from the U.S. Global Change 
Research Program (2016 Assessment), climate change will likely 
contribute to ``thousands to tens of thousands of premature heat-
related deaths in the summer'' in the United States in the years 
ahead.\48\ Indeed, the heat wave in summer 2021 discussed above 
resulted in excess heat-related deaths of 143 in Washington, 119 in 
Oregon, 13 in California, and 619 in British Columbia according to 
public health authorities.\49\ The 2016 Assessment also notes climate 
change is likely to result in ``meteorological conditions increasingly 
conducive to forming ozone over most of the United States,'' which is 
likely to result in ``premature deaths, hospital visits, lost school 
days, and acute respiratory symptoms.'' \50\ The 4th National Climate 
Assessment also notes that, in addition to the immediate hazard to life 
and property, climate change-induced wildfires will result in direct 
hazards to human health in the form of burns, smoke inhalation, 
exacerbation of particulate and ozone pollution, and negative impacts 
on water quality.\51\
---------------------------------------------------------------------------

    \46\ 74 FR 66495 (Dec. 15, 2009).
    \47\ 81 FR 54422 (Aug. 15, 2016).
    \48\ U.S. Global Change Research Program, The Impacts of Climate 
Change on Human Health in the United States: A Scientific 
Assessment--Executive Summary at 6 (2016).
    \49\ U.S. Department of Health and Human Services, Office of 
Climate Change and Health Equity, Climate and Health Outlook: 
Extreme Heat (June 2022), https://www.hhs.gov/sites/default/files/climate-health-outlook-june-2022.pdf; British Columbia, ``Minister's 
Statement on 619 Lives Lost During 2021 Heat Dome'' (June 7, 2022). 
https://news.gov.bc.ca/26965.
    \50\ Methane also directly contributes to adverse air quality 
because it is a chemical precursor to ozone.
    \51\ U.S. Global Change Research Program, Impacts, Risks, and 
Adaptation in the United States: Fourth National Climate Assessment, 
Volume II--Water at 154 (2018); U.S. Global Change Research Program, 
Impacts, Risks, and Adaptation in the United States: Fourth National 
Climate Assessment, Volume II--Air Quality at 514, 519 (2018); U.S. 
Global Change Research Program, Impacts, Risks, and Adaptation in 
the United States: Fourth National Climate Assessment, Volume I--
Southeast at 755 (2018).
---------------------------------------------------------------------------

    Increased intensity and frequency of extreme weather events (such 
as hurricanes and floods) from climate change also threaten human life 
and property. In the Northeast, high-tide flooding will impact low-
lying areas with increased frequencies and could result in an 
additional $6--9 billion in damages per year by 2100 in high emissions 
scenarios.\52\ In 2017, Hurricane Irma caused, in the United States, 
the deaths of 84 people and costs of approximately $50 billion (with 
Florida suffering most of these costs). In the Midwest, the Fourth 
National Climate Assessment found precipitation has increased by 
between 5% to 15% since the 1901-1960 period; the Fourth National 
Climate Assessment projects that seasonal precipitation during winter 
and spring associated with flood risk could increase by ``by up to 33% 
by the end of the century.'' \53\ Extreme precipitation events and 
river flooding could damage private property and transportation 
infrastructure and overwhelm stormwater treatment facilities, resulting 
in water quality impacts, especially in communities with combined sewer 
overflows. In the Southern Great Plains States, increased frequency and 
severity of severe floods was also projected for the southern

[[Page 31897]]

Great Plains states, potentially resulting in significant costs from 
flood damage and adaptation costs.\54\ The Fourth National Climate 
Assessment also found climate change-induced degradation of natural 
habitats, agricultural resources, water resources, and other ecological 
resources threaten the viability of subsistence and commercial 
activities that Federally recognized Indian Tribes depend on, such as 
``agriculture, hunting and gathering, fisheries, forestry, energy, 
recreation, and tourism,'' and threaten Tribal water allocations in the 
Western United States.\55\
---------------------------------------------------------------------------

    \52\ U.S. Global Change Research Program, Impacts, Risks, and 
Adaptation in the United States: Fourth National Climate Assessment, 
Volume II--Northeast at 695 (2018).
    \53\ U.S. Global Change Research Program, Impacts, Risks, and 
Adaptation in the United States: Fourth National Climate Assessment, 
Volume II--Midwest at 914-16 (2018).
    \54\ U.S. Global Change Research Program, Impacts, Risks, and 
Adaptation in the United States: Fourth National Climate Assessment, 
Volume II--Southern Great Plains at 1003-06 (2018).
    \55\ U.S. Global Change Research Program, Impacts, Risks, and 
Adaptation in the United States: Fourth National Climate Assessment, 
Volume II--Tribes and Indigenous Peoples at 579 (2018).
---------------------------------------------------------------------------

    Increased severe whether phenomena caused by climate change further 
threaten human health by wreaking havoc on public services and 
infrastructure. Hurricane Nicholas in the Gulf of Mexico in September 
2021 caused widespread flooding and weeks of blackouts on the U.S. Gulf 
Coast, much as the increasingly long wildfire season in California is 
now routinely accompanied by threats of rolling blackouts. The summer 
2021 heat wave that blanketed the Western United States damaged 
transportation infrastructure, closing multiple lanes on Interstate 5 
and causing trains to operate at reduced speeds as a precaution against 
the potential deformation of rail tracks. Earlier, the 2017 Atlantic 
hurricane season produced the second and third costliest hurricanes in 
U.S. history, hurricane Harvey and Hurricane Maria. Hurricane Harvey 
caused more than 60 inches of rainfall over the Texas Gulf Coast, 
including the Houston metro area, and resulted in at least 68 direct 
casualties and approximately $125 billion in storm-related damage.\56\ 
Hurricane Maria caused widespread devastation in Puerto Rico, resulting 
in approximately $90 billion dollars in damage and the near total loss 
of electric, water, and telecommunication infrastructure across the 
island, and electrical outages persisted for months across much of the 
island.\57\
---------------------------------------------------------------------------

    \56\ Eric S. Blake and David A. Zelinsky. NOAA National 
Hurricane Center. `National Hurricane Center Tropical Cyclone 
Report.'' May 9, 2018. https://www.nhc.noaa.gov/data/tcr/AL092017_Harvey.pdf.
    \57\ Richard J. Pasch, Andrew B. Penny, and Robbie Berg. NOAA 
National Hurricane Center. ``National Hurricane Center Tropical 
Cyclone Report: Hurricane Maria.'' February 14, 2019. At page 7. 
https://www.nhc.noaa.gov/data/tcr/AL152017_Maria.pdf.
---------------------------------------------------------------------------

    Pipeline infrastructure is similarly vulnerable to the impacts of 
climate change. For example, well-documented threats to pipeline 
infrastructure from natural force damage (which includes incidents 
caused by acts of nature such as flooding, land movement, and 
lightning) are likely to be exacerbated by climate change. On April 11, 
2019, PHMSA published an advisory bulletin on the threat that severe 
flooding can have on pipeline integrity, especially at water 
crossings.\58\ As described in further detail in the advisory bulletin, 
flooding and related earth movements can cause damage to pipelines in 
and around water crossings from direct water force, impacts from 
debris, added strain on pipeline structures through changes in loading 
conditions, and other means. Flooding can also threaten pipeline 
integrity by causing damage to aboveground, safety-critical components 
such as valves, pressure regulators, relief devices, and pressure 
sensors. A weather-induced failure of a gas pipeline can result in 
releases that threaten public safety and further contribute to climate 
change. On May 2, 2019, PHMSA issued another advisory bulletin to 
remind operators of the risks to pipeline facilities from large earth 
movement, including subsidence and erosion events that can be 
intensified due to climate change.\59\ PHMSA issued an update to this 
advisory bulletin on June 2, 2022, noting recent incidents and 
accidents underscoring the risks described in Advisory Bulletin ADB-
2019-02.\60\ This most recent bulletin notes that changing weather 
patterns due to climate change can weaken soil stability, increasing 
the likelihood of earth movement damage to pipeline facilities.
---------------------------------------------------------------------------

    \58\ PHMSA, ``Pipeline Safety: Potential for Damage to Pipeline 
Facilities Caused by Flooding, River Scour, and River Channel 
Migration,'' 84 FR 14715 (Apr. 11, 2019) (Advisory Bulletin ADB-
2019-01).
    \59\ PHMSA, ``Pipeline Safety: Potential for Damage to Pipeline 
Facilities Caused by Earth Movement and Other Geological Hazards,'' 
84 FR 18919 (May 2, 2019) (Advisory Bulletin ADB-2019-02).
    \60\ PHMSA, ``Pipeline Safety: Potential for Damage to Pipeline 
Facilities Caused by Earth Movement and Other Geological Hazards,'' 
87 FR 22576 (June 2, 2022) (Advisory Bulletin ADB-2022-01).
---------------------------------------------------------------------------

    PHMSA has also documented serious pipeline integrity threats from 
hurricanes in an advisory bulletin published on September 1, 2011, 
titled ``Pipeline Safety: Potential for Damage to Pipeline Facilities 
Caused by the Passage of Hurricanes.'' \61\ This advisory bulletin 
notes that hurricanes can directly damage pipelines, cause submerged 
pipelines to become exposed, or otherwise cause pipeline facilities to 
become a hazard to navigation. The advisory bulletin also noted that in 
2005, Hurricane Katrina and Hurricane Rita caused extensive damage to 
onshore and offshore oil and gas production and transportation 
infrastructure in the Gulf of Mexico, which took substantial time and 
resources to contain and remediate. PHMSA expects more severe and 
frequent hurricanes will amplify the risk of damage to pipeline 
facilities, to the detriment of coastal communities, environments, and 
the reliability of the U.S. oil and gas industry.
---------------------------------------------------------------------------

    \61\ PHMSA, ``Pipeline Safety: Potential for Damage to Pipeline 
Facilities Caused by the Passage of Hurricanes,'' 76 FR 54531 (Sept. 
1, 2011) (Advisory Bulletin ADB-11-050).
---------------------------------------------------------------------------

    Finally, these and other consequences of climate change have been, 
and are expected to continue to be, disproportionately borne by 
vulnerable populations in the United States--in particular by minority 
and low-income populations, outdoor laborers, children, and the 
elderly.\62\ Some communities of color may be uniquely vulnerable to 
climate change health impacts in the United States because they live in 
areas where the impacts of climate change (e.g., extreme temperatures 
and flooding) are likely to be the most significant, and because these 
communities tend to have limited adaptive opportunities due to a 
greater dependence on climate-sensitive resources (such as local water 
and food supplies), economic opportunities (e.g., seasonal labor), and 
limited access to social and information resources. The 2016 scientific 
assessment on the Impacts of Climate Change on Human Health similarly 
found that social determinants of health (e.g., access to healthcare, 
economic stability) are highly likely to contribute to climate change-
related health impacts.\63\ And insofar as gas transmission and gas 
gathering pipeline infrastructure is often located in the vicinity of 
socially vulnerable populations,\64\ those populations would face the 
greatest risks in the event of a release from a gas pipeline damaged by 
climate change-induced extreme weather events.
---------------------------------------------------------------------------

    \62\ U.S. Global Change Research Program, The Impacts of Climate 
Change on Human Health in the United States: A Scientific 
Assessment--Executive Summary at 6 (2016).
    \63\ U.S. Global Change Research Program, The Impacts of Climate 
Change on Human Health in the United States: A Scientific Assessment 
at 21 (2016).
    \64\ See Emanuel et al., ``Natural Gas Gathering and 
Transmission Pipelines and Social Vulnerability in the United 
States,'' 5 GeoHealth (June 2021).
---------------------------------------------------------------------------

C. Methane Emissions From Gas Pipeline Facilities

    Most gas produced or consumed in the United States is transported 
by a gas

[[Page 31898]]

pipeline at some stage of its lifecycle. PHMSA is, by statute (49 
U.S.C. 60101 et seq.), responsible for regulating the interstate 
transportation of gas by pipeline facilities, which can include the 
gathering, transmission, and distribution of natural gas as well as 
other gases regulated under parts 191 and 192.\65\ Federal law, 
however, provides that the certified State agencies have jurisdiction 
to regulate purely intrastate gas pipeline facilities. Certain 
certified State programs may also inspect interstate pipelines, such as 
interstate distribution systems. Both Federal and State regulation of 
gas pipeline facilities has historically been directed toward the 
immediate, direct risks to public safety (and indirect risks to the 
environment) associated with the ignition of natural gas releases--less 
so on the direct threat to environmental risks, including those risks 
posed by un-ignited, released methane, that invariably contribute to 
climate change.\66\
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    \65\ Parts 191 and 192 govern not only natural gas, but also any 
``flammable gas, or gas which is toxic or corrosive.'' See 
Sec. Sec.  191.3 and 192.3 (definitions of ``gas''). Consequently, 
the proposed revisions to parts 191 and 192 within this NPRM would 
apply not only to natural gas pipelines but also to other gas 
pipeline governed by parts 191 and 192.
    \66\ PHMSA acknowledges that in revising its Pipeline Safety 
Regulations over the years, it has identified environmental benefits 
of those efforts in much the same way that it has identified other 
benefits (e.g., reduced compliance cost for operators, equity, etc.) 
of those rulemakings. However, PHMSA submits those non-safety 
benefits were generally presented as secondary benefits of safety-
focused regulatory amendments.
---------------------------------------------------------------------------

1. Gas Pipeline Facilities
    PHMSA regulations cover several types of gas pipeline facilities, 
including gas gathering pipelines, gas transmission pipelines, gas 
distribution pipelines, LNG facilities, and UNGSFs.
Gathering Pipelines
    A gas gathering pipeline is defined in Federal regulations at Sec.  
192.3 as a pipeline that transports gas from a production facility to a 
transmission pipeline or main. More generally, these pipelines 
``gather'' gas from production facilities for transport to a gas 
processing plant for further transportation across transmission 
pipelines. The precise points where a gathering pipeline begins and 
ends are defined in Sec. Sec.  192.8 and 192.9 and the first edition of 
American Petroleum Institute (API) Recommended Practice 80, 
``Guidelines for the Definition of Onshore Gas Gathering Lines.'' \67\
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    \67\ API, Recommended Practice 80: Guidelines for the Definition 
of Onshore Gas Gathering Lines (Apr. 2000) (API RP 80).
---------------------------------------------------------------------------

    Section 192.9(b) provides that offshore gas gathering pipelines are 
generally subject to the same part 192 requirements as gas transmission 
pipelines. Section 192.8 also defines three types of regulated onshore 
gas gathering pipelines subject to part 192 requirements: Type A, Type 
B, and Type C gathering pipelines. Operators reported 8,290 miles of 
Type A pipelines, 3,078 miles of Type B pipelines, and 5,706 miles of 
offshore gathering lines in their 2021 annual reports. Type C gathering 
line operators will be required to submit their first annual report for 
calendar year 2022 in 2023; PHMSA estimates that there are 
approximately 90,000 miles of Type C gathering lines.\68\ Type A and 
Type B gathering pipelines are located in Class 2, Class 3, or Class 4 
locations. Type A gathering pipelines are higher-pressure pipelines and 
subject to most part 192 safety requirements applicable to gas 
transmission pipelines, while Type B gathering pipelines are lower 
pressure pipelines subject to a smaller subset of specific part 192 
safety requirements listed in Sec.  192.9(d). The Type C gathering 
pipeline designation was established in a final rule titled ``Pipeline 
Safety: Safety of Gas Gathering Pipelines: Extension of Reporting 
Requirements, Regulation or Large, High-Pressure Lines, and Other 
Related Amendments'' published on Nov. 15, 2021.\69\ Type C gathering 
pipelines are located in Class 1 locations, have an outside diameter 
greater than or equal to 8.625 inches, and operate at high 
pressure.\70\ These pipelines are subject to scaled safety requirements 
in Sec.  192.9(e), with more part 192 safety requirements applicable as 
a function of the risk posed to public safety based on the diameter of 
the Type C segment (which affects the potential energy of a pipeline 
rupture and explosion) and its proximity to nearby populated 
structures. For example, Sec.  192.9(e) provides that while all Type C 
lines are required to carry out a damage prevention program, leakage 
survey requirements only attach to either the largest (outside diameter 
greater than 16 inches) Type C lines, or those Type C lines with 
smaller diameters (8.625 inches through 16 inches) near buildings 
intended for human occupancy.
---------------------------------------------------------------------------

    \68\ See PHMSA, Doc. No. PHMSA-2011-0023, ``Regulatory Impact 
Analysis: Pipeline Safety: Expansion of Gas Gathering Regulation 
Final Rule'' at 11, 15 (Nov. 2021) (Gas Gathering RIA).
    \69\ 86 FR 63266 (Gas Gathering Final Rule). Certain smaller-
diameter Type C gas gathering pipelines are the subject of a 
temporary enforcement discretion whereby PHMSA has committed not to 
pursue enforcement action against those pipelines for alleged 
violations of certain part 192 safety requirements before May 17, 
2024. See PHMSA, ``Notice of Limited Enforcement Discretion for 
Particular Type C Gas Gathering Pipelines'' (July 8, 2022), https://www.phmsa.dot.gov/news/notice-limited-enforcement-discretion-particular-type-c-gas-gathering-pipelines.
    \70\ See the pressure criteria in the second column of table 1 
in Sec.  192.8(c)(2).
---------------------------------------------------------------------------

    Type A, Type B, and certain Type C gathering pipelines (namely, 
those Type C gathering pipelines that are installed, replaced, 
relocated, or otherwise changed after May 16, 2023) must comply with 
the design, construction, initial inspection, and initial testing 
requirements applicable to gas transmission lines, and must therefore 
be constructed from similar materials. According to annual reports 
submitted to PHMSA, gas transmission pipelines and Type A and Type B 
regulated onshore gathering lines are generally made from steel and, to 
a lesser extent, polyethylene plastic. An operator may also use two 
polyamide compounds, PA-11 and PA-12. Composite materials \71\ may be 
used with notification to PHMSA on a Type C gathering pipeline. PHMSA 
expects that most Type C gathering pipelines, which have operational 
characteristics similar to gas transmission and Type A regulated gas 
gathering pipelines, are made of steel, but Type C pipelines existing 
prior to May 16, 2023, may have been constructed with non-standard 
materials.
---------------------------------------------------------------------------

    \71\ ``Composite materials'' are defined in Sec.  192.3 as 
materials used to make pipe or components manufactured with a 
combination of either steel and/or plastic and with a reinforcing 
material to maintain its circumferential or longitudinal strength.
---------------------------------------------------------------------------

Transmission Pipelines
    A gas transmission pipeline is defined in Sec.  192.3 to include 
any pipeline, other than a gathering pipeline, that transports gas from 
a gathering pipeline or storage facility to a distribution center, 
storage facility, or large-volume customer such as a gas power station 
or an LNG facility. In 2021, operators reported 301,524 miles of gas 
transmission pipelines on their annual reports. Additionally, a 
pipeline other than a gathering pipeline that operates at a hoop stress 
of 20% or more of the specified minimum yield strength (SMYS),\72\ or 
that transports gas within a storage field, is also classified as a gas 
transmission pipeline. An operator may also voluntarily designate a 
pipeline as a gas transmission pipeline that would otherwise meet the 
definition of a gas gathering pipeline or gas distribution

[[Page 31899]]

pipeline. Gas transmission pipelines are typically steel, larger 
diameter (6 to 48 inches), high-pressure lines (operating pressures 
generally between 200 and 1500 pounds per square inch) transporting 
large volumes of gas long distances.
---------------------------------------------------------------------------

    \72\ SMYS is defined in 49 CFR 192.3 to mean specified minimum 
yield strength, which is a measure of tensile strength. As an 
example, Trade B pipe made to API 5L specification has a specified 
minimum yield strength (SMYS) of 35,000 pounds per square inch (psi) 
40 percent of SMYS (35,000 x 0.40) is 14,000 psi.
---------------------------------------------------------------------------

Distribution Pipelines
    A gas distribution pipeline is defined at Sec.  192.3 as a pipeline 
other than a gas transmission pipeline or gathering pipeline. 
Distribution pipelines are typically a part of a distribution system 
that transports gas received from a transmission pipeline by a 
distribution center (often located at the so-called ``city gate''), and 
then to homes and businesses through a network of gas mains and service 
pipelines.\73\ A gas distribution service pipeline feeds gas to one or 
two customers, while a distribution main is the common source of supply 
for two or more service pipelines. In 2021, distribution operators 
reported 2,300,793 miles of gas distribution mains and service lines on 
their annual reports. While virtually all gas transmission piping is 
fabricated from steel, gas distribution pipeline materials vary 
depending on the vintage and usage. Modern systems are predominately 
polyethylene plastic and protected steel (i.e., coated with corrosion-
resistant materials and/or equipped with cathodic protection); older 
systems may contain cast-iron or bare (not protected) steel piping. 
Distribution pipelines made of copper, wrought iron, and non-
polyethylene plastic also exist but are less common.
---------------------------------------------------------------------------

    \73\ Under 49 U.S.C. 60105 and 60106, States may assume safety 
authority over intrastate gas pipelines through certifications and 
agreements with PHMSA. Currently, the District of Columbia, Puerto 
Rico, and all States except Alaska and Hawaii exercise safety 
oversight authority over all intrastate gas distribution pipelines 
within State lines. These State programs conduct regular inspections 
and enforce State safety regulations over intrastate distribution 
pipelines. See PHMSA's State Programs website for more information: 
https://www.phmsa.dot.gov/working-phmsa/state-programs/state-programs-overview (last accessed Dec. 20, 2022).
---------------------------------------------------------------------------

LNG Facilities
    An LNG facility is defined in Federal regulations at 49 CFR part 
193 \74\ as a gas pipeline facility that is used for liquefying natural 
gas or synthetic gas or transferring, storing, or vaporizing LNG. LNG 
means natural gas or synthetic gas having methane as its principal 
constituent, and which has been changed to a liquid, thereby reducing 
the volume of the gas to facilitate storage and long-distance 
transportation. LNG facilities are subject to the safety requirements 
in part 193. LNG facilities include gas pipeline facilities that either 
change gas into LNG (liquefaction) or that change LNG back into a vapor 
or gaseous state (vaporization). LNG facilities also include transfer 
piping systems that transfer LNG between any of the following: 
liquefaction process facilities, storage tanks, vaporizers, 
compressors, cargo transfer systems, and facilities other than gas 
pipeline facilities. In 2021, operators reported 168 in-service LNG 
facilities on their annual reports.
---------------------------------------------------------------------------

    \74\ Part 193 requirements may change as a result of regulatory 
amendments proposed in a forthcoming notice of proposed rulemaking 
issued under RIN 2137-AF45. PHMSA's references to part 193 within 
this NPRM--including the proposed amended regulatory text at its 
conclusion--reflect current regulatory text and organization.
---------------------------------------------------------------------------

Underground Natural Gas Storage Facilities
    Finally, an UNGSF is defined at Sec.  192.3 as a gas pipeline 
facility that stores natural gas underground incidental to the 
transportation of natural gas, including: (1) a depleted hydrocarbon 
reservoir; (2) an aquifer reservoir; or (3) a solution-mined salt 
cavern. In addition to the storage reservoir or cavern itself, an UNGSF 
includes: injection, withdrawal, monitoring, and observation wells; 
wellbores and downhole components; wellheads and associated wellhead 
piping; wing-valve assemblies that isolate the wellhead from connected 
piping beyond the wing-valve assemblies; and any other equipment, 
facility, right-of-way, or building used in the underground storage of 
natural gas. Most underground natural gas storage occurs in depleted 
natural gas reservoirs. UNGSFs are subject to specific safety 
requirements set forth in Sec.  192.12.
2. Sources of Emissions From Gas Pipeline Facilities
    Emissions of methane and other gases subject to PHMSA's regulations 
under part 192 occur in all sectors of the natural gas industry--from 
production/extraction facilities, gathering pipelines, processing 
facilities (where the gas is made suitable for transportation and use), 
transmission pipelines, distribution pipelines, and end user 
facilities.\75\ Emissions occur during normal operation, routine 
maintenance, and abnormal conditions (such as incidents). Gas pipeline 
facilities emit methane and other gases from ``fugitive emissions'' 
from system upsets (incidents and abnormal operations that result in 
the release of gas); unintentional leaks from line pipe, flanges, 
valves, meter sets, and other equipment; and intentional releases (such 
as when a gas pipeline facility is blown down for repairs or 
maintenance or through pressure relief device operation as designed or 
configured). Older pipelines and pipelines known to leak based on their 
material (e.g., legacy materials such as cast iron, wrought iron, 
unprotected steel, and certain historic plastics), design, or past 
operating and maintenance history are generally more susceptible to 
leaks.
---------------------------------------------------------------------------

    \75\ Although the evaluation of release data discussed in this 
section II.C.2 and subsequent sections is focused on the location, 
frequency, and severity of leaks on natural gas pipeline facilities, 
that analysis is largely applicable to leaks on other part 192-
regulated gas pipeline facilities. Indeed, certain part 192-
regulated gas pipeline facilities (e.g., gas pipeline facilities 
transporting hydrogen gas) may be particularly susceptible to leaks 
because of (inter alia) the smaller size of hydrogen gas molecules 
compared to methane molecules of which natural gas is mostly 
composed.
---------------------------------------------------------------------------

    The EPA compiles and publishes data on the magnitude and sources of 
methane emissions from gas gathering, transmission, and distribution 
pipelines and other gas pipeline facilities. The EPA has two 
complementary programs for characterizing GHG emissions such as 
methane: the Inventory of Greenhouse Gas Emissions and Sinks 
(Greenhouse Gas Inventory, or GHGI), and the Greenhouse Gas Reporting 
Program (GHGRP).
     The 2022 GHGI estimates a time series of total annual 
national-level GHG emissions across sectors of the economy using a 
large number of data inputs including GHGRP, research studies, and 
national and subnational activity data sets. The most recent final GHGI 
(2022 GHGI) includes estimates from 1990 through 2020.\76\ The GHGI 
includes estimates of GHG emissions from sources including fossil fuel 
combustion, industrial processes, agriculture, and transportation. The 
GHGI is updated annually.
---------------------------------------------------------------------------

    \76\ EPA, Inventory of U.S. Greenhouse Gas Emissions and Sinks: 
1990-2020 (Apr. 15, 2022) (2022 GHGI).
---------------------------------------------------------------------------

     The Greenhouse Gas Reporting Program (GHGRP) has, since 
2010, collected facility-level emissions data from certain large GHG 
emission sources, fuel and industrial gas suppliers, and CO2 
injection sites in the United States including large suppliers or 
facilities that emit more than 25,000 metric tons of CO2 
equivalent per year.\77\
---------------------------------------------------------------------------

    \77\ In the GHGI, the EPA estimates that the global warming 
potential of 1 metric ton of CH4 is equivalent to 25 
metric tons of CO2 over a 100-year time horizon. (40 CFR 
98, Table A-1 to Subpart A of Part 98).
---------------------------------------------------------------------------

    For the 2020 reporting year, subpart W facilities in the GHGRP 
included 164 reports from distribution operators and 45 reports from 
gas transmission pipeline operators. However, GHGRP

[[Page 31900]]

data is not congruent with the pipelines subject to PHMSA regulations. 
For example, the 45 gas transmission pipeline operators submitting 
reports under GHGRP for the 2020 reporting year correspond only to 
approximately \2/3\ of gas transmission pipeline mileage 
nationwide.\78\ Additionally, certain entire sectors, such as the 
agricultural sector, are not required to report to the GHGRP. The 
creation of the GHGRP was provided for by Congress in the fiscal year 
2008 Consolidated Appropriations Act (Pub. L. 110-161) and promulgated 
under section 114 of the Clean Air Act.\79\ Data must be reported to 
EPA by March 31 of each year. Petroleum and natural gas industries, 
including natural gas distribution facilities, onshore natural gas 
gathering and boosting, onshore natural gas transmission pipelines 
(including compression), and LNG storage/terminal facilities are 
covered under 40 CFR part 98, subpart W.
---------------------------------------------------------------------------

    \78\ One operator may submit multiple GHGRP reports if they 
operate multiple systems or in multiple states.
    \79\ 42 U.S.C. 7414.
---------------------------------------------------------------------------

    The GHGI estimates for methane emissions are generally developed by 
multiplying an emissions factor by an activity factor. For example, for 
distribution main leaks, an emission factor in kg CH4 per 
mile by material type is multiplied by mileage data by material type 
(an activity factor) from PHMSA annual reports. Each itemized emissions 
segment or source in the GHGI has its own emissions factor, in many 
cases derived from GHGRP data. EPA annually updates the methodology in 
the GHGI to improve accuracy and completeness.\80\ The current GHGI 
quantifies emissions from leaks in pipelines using the following 
approaches and data:
---------------------------------------------------------------------------

    \80\ Refer to tables 3.6-2, 3.6-6, and 3.6-17 of Annex 36 of the 
2022 GHGI for more information on the methodologies or data sources 
used by EPA to develop each emissions factor.
---------------------------------------------------------------------------

     Gathering pipeline leaks. Emission factors are developed 
using year specific GHGRP data. GHGRP data are used as the activity 
factor as well. GHGRP data are reported by material type.
     Transmission pipeline leaks. Data from EPA/GRI 1996 were 
used to develop the emission factor. PHMSA mileage data are used as the 
national activity factor.
     Distribution pipeline leaks. Data from Lamb et al. 2015 
were combined with EPA/GRI 1996 to develop the material-specific 
emission factors. PHMSA main mileage and service line count data are 
used as the national activity factor, by material type.
    Recent research using modern leak detection equipment indicates 
that overall fugitive methane emissions from gas pipeline facilities 
may be significantly underestimated in current methane emissions 
estimates. The methodology of multiplying an activity factor (such as 
pipeline mileage) by an emissions factor to extrapolate an estimate of 
overall emissions for a given source is considered a ``bottom-up'' 
approach that can be contrasted with a ``top-down'' approach taking 
total emissions measured at larger (e.g., national) scales and 
attributing emissions to specific sources through modeling. Top-down 
approaches regularly estimate higher total emissions in the atmosphere 
than have been estimated by bottom-up approaches (sometimes referred to 
as the ``top-down/bottom-up gap''). For example, recent analysis using 
top-down methods from the International Energy Agency (IEA) released in 
early 2022 found that global methane emissions from the energy sector 
are about 70% greater than the official statistics reported by national 
governments.\81\ IEA used satellite-based sensor technologies, 
atmospheric methane measurements, and data processing techniques to 
capture total emissions over large areas and attribute those emissions 
to facility-level sources, rather than by simply multiplying activity 
factors by bottom-up emissions factors. Other studies comparing the two 
approaches have consistently shown that bottom-up approaches may 
underestimate total U.S. methane emissions by 50% or more.\82\ One 
explanation suggested for the significant discrepancy in estimated 
emissions is that bottom-up methods under-sample large but infrequent 
emissions events such as malfunctions and venting, possibly due to the 
difficulty and risks associated with taking samples during such 
events.\83\ Furthermore, as discussed below, recent research also 
indicates that potential under-estimation of pipeline facility 
emissions could be particularly pronounced in connection with 
distribution and gathering pipelines. EPA has recently proposed 
adjustments to its GHGRP data collection for reporting equipment leaks 
from natural gas distribution sources (including pipeline mains and 
services, below grade transmission-distribution transfer stations, and 
below grade metering-regulating stations) and for reporting emissions 
from equipment at onshore petroleum and natural gas production and 
onshore petroleum and natural gas gathering and boosting 
facilities.\84\ Additional discussion of emissions factors for gas 
pipelines is available in the Preliminary RIA for this NPRM available 
in the rulemaking docket.
---------------------------------------------------------------------------

    \81\ IEA, Press Release, ``Methane emissions from the energy 
sector are 70% higher than official figures'' (Feb. 23, 2022), 
https://www.iea.org/news/methane-emissions-from-the-energy-sector-are-70-higher-than-official-figures. IEA's analysis may 
underestimate the full extent of methane emissions as satellite data 
used by the organization do not provide complete coverage of all 
global oil and gas operations.
    \82\ Zavala-Araiza et al., ``Reconciling Divergent Estimates of 
Oil and Gas Methane Emissions,'' 112 Proceedings of the National 
Academy of Sciences of the United States of America 11597-98 (Dec. 
22, 2015); Lyon et al., ``Constructing a Spatially Resolved Methane 
Emission Inventory for the Barnett Shale Region,'' 49 Environmental 
Science & Technology at 8147, 8154 (July 7, 2015); Alvarez et al., 
``Assessment of Methane Emissions from the U.S. Oil and Gas Supply 
Chain,'' Science 186 (June 21, 2018).
    \83\ Brandt et al., ``Methane Leakage from North American 
Natural Gas Systems,'' Science 343, 345 (Feb. 13, 2014); Zavala-
Araiza et al., 2015, at 15598; Lyon, at al., 2015, at 8147, 8155; 
Alvarez et al., 2018, at 183. The authors of the Brandt, Zavala-
Araiza, and Lyon studies also suggest that this underestimation of 
emissions could be due to (or exacerbated by) incomplete activity 
factors that omit certain emissions source activities (such as 
inaccurate component counts or even the omission of entire 
facilities). Further, the authors of the Brandt study point to 
limited sample sizes and changing technologies as other potential 
sources of error in bottom-up emissions estimates.
    \84\ EPA, ``Revisions and Confidentiality Determinations for 
Data Elements under the Greenhouse Gas Reporting Rule--Notice of 
Proposed Rulemaking'' 87 FR 36920, 36927 (June 21, 2022).
---------------------------------------------------------------------------

Methane Emissions Data--All Natural Gas Pipeline Facilities
    The 2022 GHGI estimated annual net methane emissions from U.S. 
natural gas systems in 2020 to be 6,6,137 thousand metric tons 
(kt).\85\ Gas transmission, gas distribution, transportation-related 
gas and LNG storage, and regulated gas gathering lines as determined in 
Sec.  192.8 are regulated by PHMSA. On the other hand, exploration, 
production, gas processing plants, and Type R unregulated gas gathering 
lines are not regulated by PHMSA.). Assuming approximately one third of 
gathering and boosting emissions are attributable to regulated gas 
gathering lines, approximately half of net methane emissions from 
natural gas systems are from PHMSA-regulated pipeline facilities. The 
sector classifications used in the GHGI may not correspond precisely 
with the regulatory definitions of different types of pipeline 
facilities in the Federal Pipeline Safety Regulations. In EPA's GHGI, 
the gathering and

[[Page 31901]]

boosting sources include gathering and boosting stations (with multiple 
sources on site) and gathering pipelines. Those sources include PHMSA-
regulated gas gathering lines, Type R gathering lines, and some 
pipelines and activities that are better described as production and 
not transportation.\86\ The GHGI data cited in this section is for 
natural gas systems, and therefore would be covered under the 
regulatory classifications in part 192. The EPA definition is similar 
in principle to the definition of a gas ``gathering line'' in part 192, 
although it references some gas treatment processes that could be 
classified as a ``production operation'' rather than as a gathering 
pipeline under Sec.  192.9 and the first edition of API RP 80, and 
therefore not under PHMSA's jurisdiction. However, for the purposes of 
estimating emissions from leaks and incidents on PHMSA-regulated gas 
gathering pipelines, PHMSA believes that the emissions rate associated 
with ``pipeline leaks'' from ``gathering and boosting'' piping as 
defined by EPA would not be significantly different than the emissions 
rate for gas gathering pipelines as defined by PHMSA.
---------------------------------------------------------------------------

    \85\ Natural gas systems include exploration, production, 
gathering, processing, transmission, storage, and distribution of 
gas. The 2022 GHGI inventory introduced estimates of post-meter 
emissions. Emissions from power generation are estimated elsewhere 
in the GHGI.
    \86\ 2022 GHGI. Pg. 3-90.
---------------------------------------------------------------------------

    While natural gas exploration and production (i.e., the upstream 
sector) is the single largest source category, approximately one-third 
of total methane emissions are attributed to transmission, storage, and 
distribution systems, and an additional one-fourth of total methane 
emissions is attributed to natural gas gathering and boosting systems. 
A summary of these high-level emissions estimates is shown in the table 
below and represent the net methane emissions \87\ for 2020 from 
section 3.7 and annex 3.6 of the 2022 GHGI. These figures represent 
only methane emissions and do not include, for example, CO2 
emissions from compressor station engines.
---------------------------------------------------------------------------

    \87\ Net emissions estimates include estimated emissions 
reductions from reported implementation of EPA Methane Challenge and 
Gas STAR best practices by operators in the production, transmission 
and storage and distribution sectors and estimated reductions from 
EPA regulatory requirements.

        2022 GHGI: 2020 Natural Gas Systems Net Methane Emissions
------------------------------------------------------------------------
                 Source                       Kt CH4          Percent
------------------------------------------------------------------------
Exploration and Production (excluding              1,964              32
 gathering).............................
Gathering and Boosting..................           1,500              24
Processing Plants.......................             494               8
Transmission, Storage, and LNG..........           1,625              26
Distribution............................             554               9
                                         -------------------------------
    Total...............................           6,137             100
------------------------------------------------------------------------

Methane Emissions Data--Natural Gas Distribution Pipelines
    The GHGI estimates that in 2020, approximately half of methane 
emissions from natural gas distribution systems was caused by leaks 
from and incidents on gas distribution line pipe. Leaks from customer 
meters, meter stations, and regulator stations comprise most of the 
remaining emissions. Recent studies indicate, however, that current 
methane emissions data likely significantly under-estimates methane 
emissions from gas distribution pipelines. For example, a national 
study focusing on the natural gas distribution sector estimated 
emissions from mains that were five times larger than those in the GHGI 
estimate for 2017 estimates (0.69 million metric tons of methane vs. 
0.14 million metric tons) \88\ and by extension the GHGI estimate for 
2020 as well (0.69 million metric tons of methane vs. 0.13 million 
metric tons).\89\ The current methodology for calculating the emissions 
factors from natural gas distribution main and service pipelines in the 
GHGI was most recently updated in 2016 \90\ and relies on a 1996 report 
by the U.S. EPA and the Gas Research Institute (GRI) \91\ and a 2015 
study by Lamb et. al.\92\ The 2020 study by Weller et.al. attributed 
the differences to a larger number of leaks than previously estimated 
and better quantification of the largest leaks from the distribution 
sector (so-called ``super-emitter'' leaks), which contribute 
significantly to overall emissions.\93\
---------------------------------------------------------------------------

    \88\ Weller et al., ``A National Estimate of Methane Leakage 
from Pipeline Mains in Natural Gas Local Distribution Systems,'' 54 
Environmental Science & Technology 8958, 8966 (June 10, 2020).
    \89\ EPA, Inventory of U.S. Greenhouse Gas Emissions and Sinks: 
1990-2020, Annex 3.6-1 (Apr. 15, 2022).
    \90\ U.S. EPA. ``Inventory of U.S. Greenhouse Gas Emissions and 
Sinks 1990-2014: Revisions to Natural Gas Distribution Emissions''. 
Pgs. 10-13. (April 2016). https://www.epa.gov/sites/default/files/2016-08/documents/final_revision_ng_distribution_emissions_2016-04-14.pdf.
    \91\ EPA & Gas Research Institute, Methane Emissions from the 
Natural Gas Industry (June 1996) (the 1996 GRI/EPA Report).
    \92\ Lamb et al., ``Direct Measurements Show Decreasing Methane 
Emissions from Natural Gas Local Distribution Systems in the United 
States,'' 49 Environmental Science & Technology 5161 (Mar. 31, 
2015).
    \93\ Weller et al., 2020, at 8958-59.

 2022 GHGI: 2020 Natural Gas Distribution Systems Emissions by Category
------------------------------------------------------------------------
                 Source                       Kt CH4          Percent
------------------------------------------------------------------------
Main Pipeline Leaks.....................           132.0            23.8
Service Pipeline Leaks..................            70.8            12.8
Mishaps (e.g., Incidents)...............            68.6            12.4
Meter/Regulator Stations................            44.4             8.0
Customer Meters.........................           235.4            42.5
Pipeline Blowdown.......................             2.1             0.4
Relief Device Venting...................             1.2             0.2
                                         -------------------------------
    Total...............................           554.5             100
------------------------------------------------------------------------
Note the PHMSA definition of a service pipeline in Sec.   192.3 includes
  the customer meter in most configurations.

[[Page 31902]]

    Unlike natural gas transmission systems, the GHGI separately 
estimates emissions from natural gas distribution mains and service 
pipelines by construction material.\94\ PHMSA has monitored trends in 
legacy pipe materials for years, as these materials pose safety 
risks.\95\ The GHGI data demonstrates that replacing leak-prone pipe, 
such as aging cast iron, can have a significant effect in reducing 
methane emissions from gas distribution systems. Despite dramatically 
increased natural gas production and consumption between 1990 and 2019, 
methane emissions from natural gas distribution systems have fallen 
steadily from 1,819 kt CH4 in 1990 to 554.5 kt 
CH4 in 2020 (as quantified by GHGI). This reduction in 
methane emissions corresponds to a decline in cast-iron and 
cathodically unprotected steel pipe mileage over the same period. And 
while cast iron mains currently represent less than 1 percent of total 
distribution main miles--approximately 18,000 miles of cast iron or 
wrought iron distribution main remain in place as of 2021--leaks on 
such facilities account for approximately one-fifth of GHGI's estimated 
total fugitive emissions from all natural gas distribution mains in 
2020. Additionally, PHMSA incident report data shows that cast iron 
mains are vulnerable to integrity failures resulting in incidents; 
around 8 percent of the incidents that occurred on gas distribution 
mains between 2010 and 2021 occurred on cast iron mains. GHGI and PHMSA 
data, therefore, demonstrates that replacing leak-prone materials on 
gas distribution pipelines can reduce fugitive emissions and incidents 
and suggest that similar environmental and public safety benefits could 
be achieved by upgrading gas transmission and gas gathering pipelines 
made from materials known to leak. PHMSA and its predecessor agency, 
the Research and Special Programs Administration (RSPA), have 
identified replacement of cast iron and bare steel pipe as a policy 
priority for reducing gas distribution leaks and incidents for over two 
decades. Further, on November 15, 2021, the Bipartisan Infrastructure 
Law (Pub. L. 117-57) appropriated $200 million per year for PHMSA's 
Natural Gas Distribution Infrastructure Safety and Modernization Grants 
program, which provides grant funding to municipally or community-owned 
gas distribution pipeline facilities for the purposes of replacing 
legacy pipeline facilities.\96\
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    \94\ 2022 GHGI, Annex 3.6.
    \95\ PHMSA, ``Pipe Replacement Background'' (Apr. 26, 2021), 
https://www.phmsa.dot.gov/data-and-statistics/pipeline-replacement/pipeline-replacement-background (last accessed Dec. 20, 2022).
    \96\ See PHMSA. ``Natural Gas Distribution Infrastructure Safety 
and Modernization Grants'' (Aug. 2, 2022), https://www.phmsa.dot.gov/grants/pipeline/natural-gas-distribution-infrastructure-safety-and-modernization-grants (last accessed Dec. 
20, 2022).
---------------------------------------------------------------------------

Methane Emissions Data--Natural Gas Transmission and Storage
    The GHGI estimates natural gas transmission pipelines in 2020 
emitted 1,300 kt of methane emissions, excluding storage; however, the 
causes are very different than distribution. Leaks from natural gas 
transmission line pipe represent a small share of emissions estimated 
in the GHGI: only 3.3 kt of a total 1,504 kt of net methane emissions 
from the transmission and storage sector. As shown in the table below, 
vented and fugitive emissions (i.e., leaks) from natural gas 
transmission compressor stations, compressors, and regulating and 
metering stations comprise a significant portion of total methane 
emissions from pipeline facilities. GHGI data on the natural gas 
transmission and storage segment reflects both onshore and offshore 
sources.

   2022 GHG Inventory: 2020 Natural Gas Transmission Methane Emissions
------------------------------------------------------------------------
                 Source                       Kt CH4          Percent
------------------------------------------------------------------------
Pipeline Leaks..........................             3.3             0.3
Pipeline Venting (including blowdowns              221.3            17.0
 and upset venting).....................
Station Venting (including blowdowns)...           168.9            13.0
Dehydrator Venting......................             2.6             0.2
Flaring.................................             0.6             0.0
Pneumatic Devices.......................            36.3             2.8
Compressor Station Fugitive Emissions...           702.8            54.1
Compressor Exhaust......................           164.1            12.6
                                         -------------------------------
    Total...............................         1,300.0           100.0
------------------------------------------------------------------------
Note: Pipeline venting includes releases from ruptures and other
  incidents.

    The table below shows emissions from compressor stations on natural 
gas transmission pipelines in additional detail. Emissions from 
generators includes emissions from natural gas storage facilities 
dedicated to a compressor station.

  2022 GHG Inventory: 2020 Natural Gas Transmission Compressor Station
                            Methane Emissions
------------------------------------------------------------------------
                 Source                       Kt CH4          Percent
------------------------------------------------------------------------
Fugitive Emissions......................           145.1            14.0
Reciprocating Compressor................           419.5            40.5
Centrifugal Compressor (Wet Seals)......            57.0             5.5
Centrifugal Compressor (Dry Seals)......            81.3             7.8
Engine Exhaust..........................           148.8            14.4
Turbine Exhaust.........................             1.6             0.2
Generator Engines (inc. Storage)........            13.8             1.3
Generator Turbine (inc. Storage)........           0.004             0.0
Station Venting.........................           168.9            16.3
                                         -------------------------------

[[Page 31903]]

 
    Total...............................         1,035.8           100.0
------------------------------------------------------------------------

    Additionally, the table below shows emissions from natural gas 
storage facilities.\97\
---------------------------------------------------------------------------

    \97\ The nature and use of tankage as storage incidental to the 
movement of gas by pipeline dictates whether storage facilities are 
pipeline facilities subject to the jurisdiction of 49 U.S.C. 60101, 
et seq.

     2022 GHG Inventory: 2020 Natural Gas Storage Methane Emissions
------------------------------------------------------------------------
                 Source                       Kt CH4          Percent
------------------------------------------------------------------------
Station and Compressor Fugitive                     24.5             7.6
 Emissions..............................
Reciprocating Compressors...............           102.9            32.2
Storage Wells...........................            11.3             3.5
Metering and Regulating (Transmission               75.3            23.5
 Interconnect)..........................
Metering and Regulating (Farm Taps &                17.5             5.5
 Direct Sales)..........................
Dehydrator Venting......................             4.5             1.4
Flaring.................................             1.1             0.4
Engine Exhaust..........................            22.7             7.1
Turbine Exhaust.........................             0.2             0.1
Generators (inc. Transmission)..........            13.8             4.3
Pneumatic Devices.......................            17.3             5.4
Station Venting.........................            28.9             9.0
                                         -------------------------------
    Total...............................           319.9           100.0
------------------------------------------------------------------------

    Though the 2022 GHGI does not track relief and control device 
releases as a separate emissions source for natural gas transmission 
and storage facilities, PHMSA incident report data indicates that such 
releases are a significant contributor to methane emissions. A pressure 
relief device is designed to allow gas to escape from a pressurized 
system to protect the system from overpressurization. Relief devices 
and other pressure control devices are critical to the safe operation 
of a pipeline system when they function as intended. However, a poorly 
designed or poorly configured pressure relief device can result in 
releases of gas to the atmosphere larger than strictly necessary to 
protect pipeline integrity. Conversely, a relief device or control 
device that fails to release gas as designed or configured will not 
provide adequate protection from overpressurization and may rupture, 
presenting a hazard to public safety and the environment. Between 2010 
and 2021, PHMSA incident report data yields that ``malfunction of 
control/relief equipment,'' including control valves, relief valves, 
pressure regulators, and emergency shutdown device system failures,\98\ 
was listed as the cause for 30% of incidents and 21% of unintentional 
gas emissions from reportable incidents on gas transmission pipelines. 
Approximately 95% of these incidents are reportable due to reported 
unintentional emissions exceeding 3 MMCF, although these incidents are 
occasionally reportable because repair costs or other monetary damages 
exceed the property damage criterion in Sec.  191.3. Out of these 480 
incidents, 114 involved the failure of a relief valve. The next most 
commonly involved component in these failures were emergency shutdown 
devices, which resulted in 54 incidents over this time period.
---------------------------------------------------------------------------

    \98\ See PHMSA, Form F 7100.2, ``Incident Report -Gas 
Transmission and Gathering System'' at section G6 (May 2022).
---------------------------------------------------------------------------

    Recent studies also suggest that current methane emissions data 
likely underestimates emissions from natural gas transmission and 
storage facilities. The emission factor for transmission pipeline leaks 
in the GHGI is based on volume 9 of the 1996 GRI/EPA Report. The 
emissions factor is derived from the frequency of leak repairs reported 
on operators' annual reports to RSPA and self-reported leak 
measurements from distribution mains, both collected in 1991.\99\ The 
authors of one study noted that the difficulty in accurately measuring 
abnormal ``super-emitter'' events from natural gas transmission and 
storage facilities using on-site measurements suggests that bottom-up 
methodologies underestimate emissions from ``super-emitter'' events, 
and consequently total emissions.\100\ For example, the 1996 GRI/EPA 
Report relied on limited RSPA incident report data which did not even 
include a volumetric incident definition criterion as used under 
current PHMSA reporting requirements.\101\ The RSPA incident report 
form in 1991 similarly did not require operators to provide an estimate 
of release volume. While current methane emissions data attempts to 
address this concern by factoring in ``super-emitter'' estimates, this 
remains a source of uncertainty for any type of point-in-time 
measurement.\102\ Further, certain infrequent but significant incidents 
at UNGSFs such as the release of 86 billion cubic feet (BCF) of natural 
gas from the Aliso Canyon facility

[[Page 31904]]

failure in 2015, the release of 6 BCF of natural gas from the Moss 
Bluff facility in 2004, and the release of 143 BCF of natural gas from 
the Yaggy storage field in 2001 demonstrate both the uncertainty in 
estimating methane emissions from UNGSFs and the potential for 
substantial methane emissions (which in turn result in public safety 
harms) from such facilities.\103\
---------------------------------------------------------------------------

    \99\ EPA & Gas Research Institute, Methane Emissions from the 
Natural Gas Industry, Volume 9: Underground Pipelines. (June 1996). 
Pgs. 38 and 46.
    \100\ Zimmerle et al., ``Methane Emissions from the Natural Gas 
Transmission and Storage System in the United States,'' 49 
Environmental Science & Technology 9374 (July 21, 2015).
    \101\ See, e.g., RSPA Form F7100.2 (Rev. 3--1984), ``PHMSA Gas 
Transmission & Gathering Incident Data--mid 1984 to 2001'', 
available at https://www.phmsa.dot.gov/data-and-statistics/pipeline/distribution-transmission-gathering-lng-and-liquid-accident-and-incident-data (last accessed Jan. 4, 2023).
    \102\ See Alvarez et al., ``Assessment of Methane Emissions from 
the U.S. Oil and Gas Supply Chain,'' Science 186, Table 1 (June 21, 
2018) (finding that bottom-up quantifications of methane emissions 
may underestimate natural gas transmission and storage emissions by 
nearly 30% when compared with top-down quantifications).
    \103\ PHMSA, ``Pipeline Safety: Safe Operations of Underground 
Storage Facilities for Natural Gas,'' 81 FR 6334 (Feb. 5, 2016) 
(Advisory Bulletin ADB-2016-02).
---------------------------------------------------------------------------

Methane Emissions Data--Gathering Pipelines
    The GHGI estimates for ``natural gas gathering and boosting'' 
systems have estimated fugitive emissions from line pipe leaks that are 
much higher than for natural gas transmission systems. As shown in the 
table below, the GHGI estimates 126.7 kt of methane emissions from 
pipeline leaks in natural gas gathering and boosting systems (estimated 
at 381,909 miles in the GHGI) \104\ compared with 3.3 kt for natural 
gas transmission systems (302,252 miles). In the RIA for the 2021 Gas 
Gathering Final Rule, PHMSA estimated that there were approximately 
426,000 miles of unregulated rural gas gathering pipelines,\105\ in 
addition to the 17,064 miles of regulated offshore and onshore Type A 
and Type B regulated gas gathering pipelines reported by operators in 
2021. Additionally, the EPA mileage estimate may include mileage that 
could be considered under Sec.  192.8 to be production pipelines rather 
than gathering pipelines. The EPA mileage therefore provides an 
estimate of gathering pipeline mileage and resulting total emissions 
estimates from such facilities that may not accurately represent 
emissions from the subset of PHMSA-regulated gathering pipeline 
sources.
---------------------------------------------------------------------------

    \104\ 2022 GHGI, Annex 36 Table 3.6-7.
    \105\ Gas Gathering RIA at 15; PHMSA, ``Annual Report Mileage 
for Natural Gas Transmission and Gathering Systems.'' (Aug. 1, 
2022), https://www.phmsa.dot.gov/data-and-statistics/pipeline/annual-report-mileage-natural-gas-transmission-gathering-systems 
(last accessed Aug. 19, 2022).

2022 GHG Inventory: Natural Gas Gathering and Boosting Methane Emissions
------------------------------------------------------------------------
                 Source                       Kt CH4          Percent
------------------------------------------------------------------------
Station Combustion Slip.................           407.1              27
Station Compressors.....................           306.9              20
Station Tanks...........................           244.3              16
Station Pneumatic Devices...............           202.0              13
Pipeline Leaks..........................           126.7               8
Station Yard Piping.....................            93.3               6
Station Blowdowns.......................            44.9               3
Station Dehydrator Vents and Leaks......            25.7               2
Station Pneumatic Pumps.................            27.2               2
Pipeline Blowdowns......................             9.4               1
Station Flare Stacks....................            11.1               1
Station Separators......................             1.4               0
Station Acid Gas Removal Units..........             0.1               0
                                         -------------------------------
    Total...............................          1500.0             100
------------------------------------------------------------------------
Note: Total includes Type R gas gathering pipelines and production
  operations not regulated under part 192.

    Recent research also suggests that, as in the case of other gas 
pipeline facilities, current methane emissions data likely understates 
emissions from natural gas gathering pipelines. One study conducted in 
the New Mexico Permian Basin in 2022 estimated emissions from natural 
gas production and gathering facilities in that region that were 6.5 
times larger than GHGI estimates.\106\ In the study, methane emissions 
were estimated using a comprehensive aerial survey spanning 35,923 
square kilometers (including over 15,000 kilometers of natural gas 
pipelines) over 115 flight days. This large sample size was intended to 
better capture infrequent ``super-emitter'' events, and the study found 
that 50% of observed emissions were attributable to large emissions 
sources with average methane emissions rates greater than 308 kilograms 
per hour. Even as studies in the past few years have increasingly 
sounded the alarm that leaks from gathering pipelines and boosting 
stations are significant contributors to climate change, GHGI emissions 
factors for those facilities have decreased over the same time period 
due to changes in GHGRP inputs.\107\ Moreover, studies aiming to 
improve gas gathering pipeline emissions factors with more accurate 
data (like one conducted on the Utica Shale in 2020) \108\ suggest that 
self-reported emissions information from GHGRP reporting on which GHGI 
emissions data for gathering pipelines is based may underestimate 
actual emissions rates. Any point-in-time measurement of methane 
emissions can miss large but infrequent events (particularly 
methodologies that use smaller sample areas such as ground-based 
approaches), thus underestimating total emissions when used to 
extrapolate beyond the sample area to an entire region.\109\
---------------------------------------------------------------------------

    \106\ Chen et al., ``Quantifying Regional Methane Emissions in 
the New Mexico Permian Basin with a Comprehensive Aerial Survey,'' 
56 Environmental Science & Technology 4317 (Mar. 23, 2022) (finding 
that ``[m]idstream assets were also a significant source [of 
emissions], with 29  20 t/h [(metric tonnes per hour)] 
emitted from pipelines (including underground gas gathering 
pipelines) and 26  16 t/h emitted from compressor 
stations without a well on site'').
    \107\ GHGI emissions factors for gathering pipeline leaks were 
identified as 354.7 CH4/mile in 2017 but decreased to 
288.5 in the 2022 GHGI. See 2022 GHGI, Annex 36 Table 3.6-2. See 
also Li et al., ``Gathering Pipeline Methane Emissions in Utica 
Shale Using an Unmanned Aerial Vehicle and Ground-Based Mobile 
Sampling,'' Atmosphere (July 5, 2020) (calling for improved gas 
gathering pipeline methane emissions factors for the Utica Shale 
region based on data from both aerial surveys and ground-based 
vehicle sampling); Chen et al., 2022, at 4317-18 (observing that, 
while ``uncertainty remains about the emissions rates in the Permian 
Basin'', recent studies conducted in that region ``consistently find 
emissions significantly in excess of government estimates'').
    \108\ Li et al., ``Gathering Pipeline Methane Emissions in Utica 
Shale Using an Unmanned Aerial Vehicle and Ground-Based Mobile 
Sampling,'' Atmosphere (July 5, 2020).
    \109\ Chen et al., 2022, at 4321-22 (``[T]he clear impact of 
large emissions found by this study suggests that estimates from 
ground-based methane surveys may be underestimating total emissions 
by missing low-frequency, high-impact large emissions.'').

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

[[Page 31905]]

Methane Emissions Data--LNG Facilities
    As shown in the tables below, the GHGI estimates that blowdowns 
account for 80 percent of estimated methane emissions from LNG storage 
facilities, and nearly half of methane emissions from all LNG 
facilities.

     2022 GHG Inventory: LNG Storage Facility 2020 Methane Emissions
------------------------------------------------------------------------
                 Source                       Kt CH4          Percent
------------------------------------------------------------------------
Equipment Leaks, Compressors, Flares,                1.4              13
 etc....................................
Blowdowns...............................             8.4              80
Engine Exhaust..........................             0.6               5
Turbine Exhaust.........................             0.1               1
------------------------------------------------------------------------

     2022 GHG Inventory: LNG Import Terminal 2020 Methane Emissions
------------------------------------------------------------------------
                 Source                       Kt CH4          Percent
------------------------------------------------------------------------
Equipment Leaks, Compressors, Flares,                0.1              22
 etc....................................
Blowdowns...............................             0.2              33
Engine Exhaust..........................             0.2              45
Turbine Exhaust.........................             0.0              <1
------------------------------------------------------------------------

     2022 GHG Inventory: LNG Export Terminal 2020 Methane Emissions
------------------------------------------------------------------------
                 Source                       Kt CH4          Percent
------------------------------------------------------------------------
Equipment Leaks, Compressors, Flares,                4.0              53
 etc....................................
Blowdowns...............................             0.3               4
Engine Exhaust..........................             1.4              18
Turbine Exhaust.........................             2.0              26
------------------------------------------------------------------------

    Fugitive emissions represent the majority of estimated methane 
emissions from LNG import and export terminals. While LNG facilities 
are often designed with boil-off gas recovery systems to avoid routine 
continuous venting of natural gas during operations, methane regularly 
escapes from LNG facilities through compressor rod packing and valve 
leakage, incomplete combustion during flaring, and other various 
process venting sources.\110\ Similar to gas transmission facilities, 
additional emissions are attributable to releases from relief devices 
and O&M related venting. Likewise, fugitive emissions from gas 
treatment equipment at liquefaction plants are likely similar to those 
from comparable equipment on other pipeline or gas processing 
facilities.\111\ Methane may also be lost to the atmosphere during pipe 
transfers of LNG to or from an LNG facility, whether through loading 
for transport or off-loading for storage or vaporization. Even if 
initially captured, boil-off gas and other fugitive emissions from LNG 
facilities may still be vented directly to the atmosphere without 
combustion during normal operation.\112\ And, as with any pipe 
transporting natural gas, the pressurized piping that runs throughout 
LNG facilities is susceptible to integrity failures and other 
incidents,\113\ including pipeline leaks that can precipitate 
explosions.\114\ For example, Cheniere reported that the Sabine Pass 
LNG terminal constituted approximately 40 miles of plant piping for its 
import facilities and an additional 285 miles of plant piping for its 
first four of six liquefaction trains,\115\ and the operator of the 
Cameron LNG terminal reported approximately 255 miles of piping in 
their liquefaction project consisting of three liquefaction 
trains.\116\ In addition, Freeport LNG similarly reported its 
liquefaction project's pretreatment and three liquefaction trains 
included approximately 192 miles of plant piping, providing ample 
opportunities for methane to escape during normal and emergency 
operations.
---------------------------------------------------------------------------

    \110\ API, Compendium of Greenhouse Gas Emissions Methodologies 
for the Natural Gas and Oil Industry at 6-121 through 6-126 (Nov. 
2021).
    \111\ API, Compendium of Greenhouse Gas Emissions Methodologies 
for the Natural Gas and Oil Industry at 6-121 through 6-122 (Nov. 
2021).
    \112\ API, Compendium of Greenhouse Gas Emissions Methodologies 
for the Natural Gas and Oil Industry at 6-123 (Nov. 2021). For 
example, boil-off gas may be vented if the vapor generation rate 
exceeds the capacity of the boil-off gas compressors or the re-
liquefaction unit. API's compendium estimates typical losses at 
0.05% of total tank volume per day when boil-off gas is vented from 
an LNG storage vessel. See also Soraghan & Lee, ``LNG explosion 
shines light on 42-year-old gas rules'' EnergyWire. (June 28, 2022), 
https://www.eenews.net/articles/lng-explosion-shines-light-on-42-year-old-gas-rules/ (noting that an LNG terminal had reported 
several natural gas releases to the state Department of 
Environmental Quality, including one release of 180,000 pounds of 
methane in January 2022).
    \113\ See, e.g., PHMSA, CPF No. 4-2022-051-NOPSO, ``In the 
Matter of Freeport LNG Development LP: Notice of Proposed Safety 
Order'' at 3 (June 30, 2022), (describing the LNG release and 
natural gas vapor cloud that resulted from the June 8, 2022 incident 
at the Quintana Island LNG facility, which may have been caused by 
the overpressure and rupture of a segment of LNG transfer line 
between the facility's LNG storage tank area and its dock 
facilities).
    \114\ See, e.g., ``Algerian LNG Complex Explosion Caused by Gas 
Pipeline Leak,'' Oil & Gas Journal (Feb. 18, 2004). A gas pipeline 
leak was ultimately determined to be the cause of the Skikda, 
Algeria LNG terminal explosion on January 20, 2004, that killed 27 
people, injured 74 others, and resulted in an estimated $800 
million-$1 billion in damages to the Skikda port facilities, 
including the destruction of three of the LNG terminal's six 
liquefaction trains. See also Romero, ``Algerian Explosion Stirs 
Foes of U.S. Gas Projects,'' New York Times (Feb. 14, 2004).
    \115\ Cheniere. ``Cheniere Energy Analyst/Investor Day.'' (Apr. 
2014). Pgs. 12-13.
    \116\ Cameron LNG. https://cameronlng.com/lng-facility/economic-impact/.
---------------------------------------------------------------------------

    However, emissions for LNG facilities have proven difficult to 
estimate due to the limited availability of accurate, complete 
emissions data, with insufficient differentiation between intentional 
and fugitive emissions.\117\

[[Page 31906]]

Bottom-up methodologies for estimating LNG emissions typically use 
generalized emissions factors averaged across the entire sector despite 
significant differences between suppliers and each step of the supply 
chain.\118\ Emissions estimates using this approach may apply a single 
emissions factor to all types of LNG facilities, even though the wave 
of recently built LNG export terminals could have little in common with 
an LNG peak shaver or storage facility. Developing accurate emissions 
estimates is also hampered by selection bias. Specifically, EPA 
currently uses data reported in accordance with 40 CFR part 98, subpart 
W (i.e., GHGRP) to develop GHGI emissions factors for LNG facilities 
(with the exception of LNG storage facility blowdowns). However, 
operators of LNG facilities need only report emissions under subpart W 
if total emissions reach the reporting threshold of 25,000 metric tons 
of CO2 equivalent per year. Many LNG storage facilities fall 
under that threshold, introducing uncertainty into aggregate emissions 
calculated using only a subset of LNG storage facilities.\119\
---------------------------------------------------------------------------

    \117\ Oxford Institute for Energy Studies, Measurement, 
Reporting, and Verification of Methane Emissions from Natural Gas 
and LNG Trade: Creating Transparent and Credible Frameworks at 51 
(Jan. 2022).
    \118\ See Roman-White et al., ``LNG Supply Chains: A Supplier-
Specific Life-Cycle Assessment for Improved Emission Accounting,'' 
ACS Sustainable Chemistry & Engineering at 10857, 10861 (2021).
    \119\ EPA, Memorandum, ``Inventory of U.S. Greenhouse Gas 
Emissions and Sinks 1990-2017: Updates to Liquefied Natural Gas 
Segment'' at 2-3 (Apr. 2019). While EPA identified between 94-98 LNG 
storage facilities as active each year from 2011-2017, only 8 such 
facilities reported emissions under Subpart W during that timeframe.
---------------------------------------------------------------------------

    Further, even among those LNG facilities that report their 
emissions to EPA, there is a potential for great variation in emissions 
reported within and across reporting years due to small sample sizes: 
the small number of LNG facilities reporting emissions to EPA (only 5 
storage facilities and 11 import and export facilities as of August 
2022 \120\) make resulting methane emissions estimates susceptible to 
substantial year-to-year fluctuation and limit the predictive value of 
such estimates for subsequent years.\121\ Lastly, operators of LNG 
storage facilities are not required to report LNG storage blowdown 
emissions under GHGRP--instead, GHGI estimates for LNG storage blowdown 
emissions consist of generalized data based on a 1996 study of blowdown 
emissions on gas transmission compressor stations and UNGSFs.\122\
---------------------------------------------------------------------------

    \120\ See EPA, ``GHGRP Petroleum and Natural Gas Systems,'' 
https://www.epa.gov/ghgreporting/ghgrp-petroleum-and-natural-gas-systems#emissions-table (last accessed March 16, 2023).
    \121\ For example, in 2016, one LNG storage facility was 
responsible for more than 82% of all LNG storage facility methane 
emissions and one LNG import terminal was responsible for more than 
95% of all LNG terminal methane emissions reported to EPA under 
Subpart W. EPA, Memorandum, ``Inventory of U.S. Greenhouse Gas 
Emissions and Sinks 1990-2017: Updates to Liquefied Natural Gas 
Segment'' at 3-8 & Tables 5, 8 (April 2019).
    \122\ EPA, Memorandum, ``Inventory of U.S. Greenhouse Gas 
Emissions and Sinks 1990-2017: Updates to Liquefied Natural Gas 
Segment'' at 1 (April 2019).
---------------------------------------------------------------------------

D. The Need for Updating PHMSA Regulations To Incorporate Advanced Leak 
Detection Programs To Reduce Unintentional Releases From Gas Pipelines

    PHMSA's regulations have historically prioritized addressing public 
safety risks posed by ignition of instantaneous, large-volume releases 
or accumulated gas. This focus on public safety is vital and can 
support PHMSA's renewed and expanded commitment to addressing 
environmental risks as well. However, current regulations can allow 
leaks of methane and other gases from gas gathering, transmission, and 
distribution pipeline facilities to continue undetected and unrepaired 
for extended periods of time.\123\ This approach therefore foregoes the 
emissions reduction potential of commercially available, advanced leak 
detection technologies and practices within integrated ALDPs. This 
historical approach also forgoes opportunities for timely 
identification and remediation of leaks from gas pipelines that can 
develop into catastrophic incidents. State and voluntary industry 
efforts to improve leak detection and repair on gas pipelines are 
emerging, but are insufficient to reduce unintentional emissions of 
methane and other gases without PHMSA regulations that support and 
backstop those efforts.
---------------------------------------------------------------------------

    \123\ PHMSA notes that the limitations of current part 191 and 
192 regulations for meaningful and timely identification, repair, 
and reporting of leaks discussed in this section II.D. may be 
particularly acute in connection with the pipeline transportation of 
gaseous hydrogen, which is a much smaller molecule (with potentially 
greater leakage potential) than methane.
---------------------------------------------------------------------------

1. PHMSA Regulations Pertinent to Unintentional Releases of Methane and 
Other Gases
    PHMSA's current regulatory requirements pertaining to gas pipeline 
leak detection, repair, maintenance, and reporting reflect a focus on 
public safety risks from ignition of instantaneous, large-volume 
releases or accumulated gas while treating risks to the environment as 
less important. PHMSA maintenance requirements at part 192, subpart M 
explicitly require only a subset of unintentional releases from gas 
pipelines--namely those unintentional releases thought to create an 
actual or probable harm to public safety--need be identified, repaired, 
or reported. Nor do those maintenance requirements in the subpart M 
regulations include explicit requirements for the replacement or 
remediation of pipes known to leak based on material, design, or past 
operating and maintenance history.\124\ And PHMSA IM regulations at 
part 192 subparts O (gas transmission pipelines) and P (gas 
distribution pipelines) allow considerable operator discretion in 
determining which leaks merit repairs and the timing of those repairs. 
PHMSA reporting requirements at part 191 similarly are calibrated to 
provide information regarding instantaneous, large-volume releases 
rather than granular data on operator leak detection and repair 
efforts, or the releases of gas from those leaks.
---------------------------------------------------------------------------

    \124\ An exception is that part 192, subpart M acknowledges 
cast-iron piping's susceptibility to leakage and contains provisions 
focused on a single mechanism (graphitization-derived corrosion) for 
development of leaks, and then only after indicia of that mechanism 
have emerged. Specifically, Sec.  192.489(a) requires replacement of 
each segment of cast iron or ductile iron pipe with general 
graphitization (a type of corrosion) that could cause a fracture or 
leak. Section 192.489(b) similarly requires replacement, repair, or 
internal sealing for localized graphitization on cast and ductile 
iron pipeline segments that could result in leakage.
---------------------------------------------------------------------------

Gas Pipelines Generally
    Part 192, subpart M contains minimum maintenance requirements for 
gas gathering, transmission, and distribution pipelines.\125\ Gas 
transmission (Sec.  192.706), distribution (Sec.  192.723), offshore 
gas gathering, and Type A, Type B, and certain Type C gathering 
(Sec. Sec.  192.9 and 192.706) pipeline operators must perform periodic 
leakage surveys. When leaks are discovered, both their severity and the 
operating conditions of the pipeline are used to determine whether and 
when a repair is performed. PHMSA's subpart M requirements contain 
broad language at Sec.  192.703(c) mandating repair of all ``hazardous 
leaks . . . promptly.'' However, subpart M neither

[[Page 31907]]

defines a ``hazardous'' leak nor provides guidance on what exactly 
constitutes a ``prompt'' repair of such leaks. Although Sec.  192.1001 
describes a ``hazardous leak'' only in terms of an existing or probable 
hazard to persons or property (and not the environment), that 
regulatory definition applies only to the gas distribution system IM 
requirements in part 192, subpart P. The Sec.  192.703(c) repair 
mandate is also inapplicable to most Type C gas gathering 
pipelines.\126\
---------------------------------------------------------------------------

    \125\ Certain part 192 regulations will be revised on 
codification of a recent PHMSA rulemaking that will become effective 
on May 24, 2023. See PHMSA, ``Safety of Gas Transmission Pipelines: 
Repair Criteria, Integrity Management Improvements, Cathodic 
Protection, Management of Change, and Other Related Amendments--
Final Rule,'' 87 FR 52224 (Aug. 24, 2022) (RIN2 Final Rule). PHMSA's 
references to part 192 within this NPRM--including the proposed 
amended regulatory text at its conclusion--reflect the regulatory 
text and organization as amended by the RIN2 Final Rule unless 
otherwise noted. The RIN2 Final Rule contains enhanced repair 
criteria that can affect leak repairs, but the requirements are 
generally directed toward phenomena (cracking, corrosion-induced 
metal loss, dents) distinct from the detection, grading, and repair 
of all leaks as proposed in this NPRM.
    \126\ Only ca. 20,000 miles of the ca. 91,000 miles of Type C 
gas gathering pipelines are subject to Sec.  192.703(c). PHMSA, Doc. 
No. PHMSA-2011-0023-0488, ``Regulatory Impact Analysis for Gas 
Gathering Final Rule'' at 11, 15 (Nov. 2021).
---------------------------------------------------------------------------

    Part 191 reporting requirements similarly reflect PHMSA's 
historical focus on public safety risks from ignition of instantaneous, 
large-volume releases or accumulated gas.\127\ Incident reports for gas 
distribution (Form F7100.1), transmission and part-192 regulated 
gathering (Form F7100.2), and Type R gathering pipelines (Form 
F7100.2.2) provide limited information regarding unintentional 
releases, as only unintentional releases of at least 3 MMCF need be 
reported. And while annual reports for gas distribution (Form F7100.1-
1), transmission and part-192 regulated gathering (Form F7100.2-1), and 
Type R gathering pipelines (Form F7100.2-3) include information on the 
number of leaks repaired in the preceding calendar year, the 
instructions for those annual report forms expressly exclude reporting 
of repairs on a broad category of leaks: releases that can be corrected 
by ``lubrication, adjustment, or tightening'' are not considered 
``leaks'' for annual reporting of repairs.\128\ The instructions for 
annual reports other than for gas distribution pipelines also do not 
require reporting of repairs of any leaks other than leaks that are 
hazardous; and the instructions for all annual report forms 
characterize leaks as ``hazardous'' with respect to public safety, 
omitting mention of hazards to the environment. Further, none of 
PHMSA's annual reports require operators to submit information on 
either the total number of leaks detected in the reporting period, the 
rolling tally of all unrepaired leaks, or estimated emissions 
associated with leaks during the reporting period.
---------------------------------------------------------------------------

    \127\ PHMSA annual and incident forms and instructions discussed 
in this paragraph can be found on PHMSA's website at https://www.phmsa.dot.gov/forms/operator-reports-submitted-phmsa-forms-and-instructions. https://www.phmsa.dot.gov/forms/operator-reports-submitted-phmsa-forms-and-instructions.
    \128\ PHMSA annual reporting requirements for part 193-regulated 
LNG facilities contain a similar exception from leak reporting 
requirements. See PHMSA, Form 7300.1-3, ``Annual Report Form for 
Liquefied Natural Gas Facilities (Oct. 2014); PHMSA, Instructions 
for Form 7300.1-3 at 4 (Oct. 2014) (stating that ``a non-hazardous 
release that can be eliminated by lubrication, adjustment, or 
tightening is not a leak'').
---------------------------------------------------------------------------

    Lastly, only gas transmission pipelines are required to provide 
geospatial data on their pipeline systems in accordance with the NPMS 
requirements at 49 U.S.C. 60132 and 49 CFR 191.29. Gas distribution and 
gathering pipelines have no requirement to provide geospatial data for 
NPMS.
Part 192--Regulated Gas Gathering Pipelines
    Operators of offshore gas gathering, Type A, Type B, and certain 
Type C gathering pipelines must comply with the leakage survey 
requirements (at Sec.  192.706) applicable to gas transmission 
pipelines and repair any hazardous leaks detected (per Sec.  192.703). 
However, most Type C gathering pipelines--specifically, those with an 
outer diameter between 8.625'' and 16'' not near an occupied building--
are, pursuant to Sec.  192.9(f)(1), not subject to any part 192 leakage 
survey and repair requirements, whether for ``hazardous'' leaks or any 
other leaks. Additionally, only offshore gas gathering and Type A 
gathering pipelines are subject to other subpart M maintenance 
requirements, including right-of-way patrols (Sec.  192.705), general 
transmission pipeline requirements for making permanent or temporary 
repairs (Sec.  192.711), and recordkeeping (Sec.  192.709). Type B and 
Type C gathering pipelines need only comply with the specific 
requirements listed in Sec.  192.9(d) and (e), which do not include 
patrol, repair, and recordkeeping requirements.
Gas Transmission Pipelines
    All gas transmission pipelines are subject to maintenance 
requirements at part 192, subpart M. Section 192.706 requires gas 
transmission operators to perform leakage surveys on most gas 
transmission pipelines at least once every calendar year. However, that 
provision does not require the use of leak detection equipment for 
those leakage surveys. Leak detection equipment is only required if a 
gas transmission pipeline is not odorized in accordance with Sec.  
192.625 and the pipeline is located in a Class 3 or Class 4 location; 
otherwise, leak detection can be by human senses only, such as visual 
observation of dead vegetation or blowing debris. Operators required to 
conduct a leakage survey with leak detection equipment must do so at 
least twice each year in Class 3 locations, and at least four times 
each calendar year in Class 4 locations.
    In addition to leakage surveys, Sec.  192.705 requires operators of 
gas transmission pipelines to have a patrolling program to monitor 
conditions on and adjacent to pipeline rights-of-way. These patrols are 
visual surveys, commonly performed using aircraft, and are intended to 
find leaks and other conditions affecting the safety and operation of 
the pipeline. Patrols commonly identify potential or current pipeline 
integrity threats caused by external changes, including construction, 
excavation, blasting, earth movements, and flooding. Information 
gathered from these patrols can prevent further damage to the pipeline 
or target leakage surveys or integrity assessments to locations that 
may have been damaged. This can prevent leaks, potentially fatal 
incidents, or damage that could result in shutdowns and maintenance-
related releases of methane and other gases to the atmosphere. For 
example, if an operator spots construction activity along the line, 
they can dispatch personnel to observe construction to minimize the 
risk of excavation-related damage to the pipeline. According to 
incidents reports submitted to PHMSA, such excavation damage is a 
leading cause of incidents that result in injuries and fatalities and 
pipeline breaks with very high emissions rates. The patrol frequency 
depends on the class location of the pipeline, the pipeline's diameter, 
operating pressure, terrain, weather, and other relevant factors. Gas 
transmission pipeline operators must perform patrols at least four 
times each calendar year in Class 4 locations, at least twice each 
calendar year in Class 3 locations, and at least once each calendar 
year in Class 1 and Class 2 locations. If the pipeline is located at a 
highway or railroad crossing in a Class 1 or Class 2 location, the 
minimum patrol frequency is increased to at least twice each calendar 
year. In Class 3 locations, the minimum patrol frequency at highway and 
railroad crossings is four times each calendar year.
    As explained above, Sec.  192.703(c) requires all transmission 
operators to repair leaks that are ``hazardous'' to public safety 
``promptly''--but PHMSA regulations contain few guardrails as to what 
``promptly'' means. Repair requirements at Sec.  192.711 require that 
operators take immediate temporary measures for leaks that impair the 
serviceability of a steel transmission pipeline operating above 40 
percent of SMYS if a permanent repair is not feasible.
    Section 192.711(b) requires that permanent repair be made as soon 
as feasible or as specified under the

[[Page 31908]]

operators' IM program under subpart O but does not specify when 
permanent repairs are necessary.\129\ Like the general repair 
requirement in Sec.  192.703, these requirements frame leak repair 
obligations in terms of public safety risks and use ambiguous language 
(``as soon as feasible'') to describe the timing of any repair 
obligations. In recognition of this regulatory gap, PHMSA has 
referenced the GPTC Guide in guidance and letters of interpretation on 
how operators should comply with these provisions of part 192.\130\
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    \129\ The RIN2 Final Rule will amend Sec.  192.711(b) by 
replacing the existing requirement that permanent repairs of safety-
adverse conditions on certain onshore gas transmission pipelines 
must be made ``as soon as feasible'' with a cross-reference to a new 
Sec.  192.714 prescribing repair schedules set forth in an industry 
standard. See 87 FR at 52271 (introducing a new Sec.  192.714 
referencing ASME/ANSI B31.8S-2004, Supplement to B31.8 on Managing 
System Integrity of Gas Pipelines at section 7, Figure 4 (Jan. 14, 
2005)). However, those repair schedules--which are intended for 
``anomalies and defects'' consisting of dents, corrosion metal loss, 
and cracking rather than leaks--contemplate that some repairs may 
not be required for years. The RIN2 Final Rule does not disturb the 
existing requirement to effectuate permanent repairs ``as soon as 
feasible'' for other part 192-regulated gas pipelines not subject to 
subpart O IM requirements.
    \130\ See, e.g., PHMSA, ``Distribution Integrity Management: 
Guidance for Master Meter and Small Liquefied Petroleum Gas Pipeline 
Operators'' (2013) at 2 (directing larger distribution pipeline 
operators to refer to GPTC guidelines); PHMSA, Interpretation 
Response Letter No. PI-93-009 (February 11, 1993) (recommending 
public stakeholder consult the GPTC Guide for further determination 
of instruments and techniques to be used in certain leak detection 
activities); see also PHMSA, Interpretation Response Letter No. PI-
99-0105 (December 1, 1999) (stating that the GPTC Guide ``is a 
document endorsed by us which contains information and some methods 
to assist the gas pipeline operator in complying with the 
regulations contained in 49 CFR part 192'').
---------------------------------------------------------------------------

    Subpart O requirements similarly provide little direction on how 
gas transmission pipelines that are located in HCAs \131\ must manage 
leak detection and repair, instead giving operators considerable 
discretion to determine when and how they address leaks on their 
pipelines. Subpart O requires operators to identify, prioritize, 
assess, evaluate, repair, and validate the integrity of their pipelines 
that have the potential to cause injury or death in the event of a 
failure. In addition, operators must measure IM plan performance to 
support continual improvement of their programs. Operators of gas 
transmission pipelines subject to the IM regulations may develop IM 
plans reflecting idiosyncratic choices regarding identification of 
specific integrity risks to their pipelines, selection of proper 
assessment tools; periodic assessment of the pipe for anomalies, and 
procedures for taking prompt action to address and repair anomalous 
conditions discovered through pipeline integrity assessments. 
Additionally, the subpart O regulations do not explicitly require 
operators to repair all leaks; operators can determine the precise 
timing of ``prompt'' repairs based on the operator's evaluation of risk 
to public safety. Further, Sec.  192.93 provides operators up to 6 
months from the date that an integrity assessment was performed to 
confirm discovery of an anomalous condition. Repair criteria at Sec.  
192.933 require that anomalous conditions posing the greatest risks to 
public safety be repaired immediately, but other anomalies that an 
operator determines pose less significant public safety risks need to 
be repaired within a year of discovery, or only monitored during 
subsequent risk assessments and integrity assessments for any change 
that may require remediation. Section 192.935 directs operators to take 
additional measures beyond those required elsewhere in part 192 to 
prevent, and mitigate the consequences of, pipeline failures in HCAs, 
but that provision identifies enhanced leak detection and monitoring 
programs as merely one potential item on a menu from which operators 
may choose in order to meet this requirement.\132\
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    \131\ Subpart O contains IM requirements for transmission 
pipelines in HCAs. Annual reports submitted by operators in 2020 
yields that only 7% (ca. 21,000 miles) of the 301,000 miles of gas 
transmission pipelines are subject to IM requirements at subpart O.
    \132\ Amendments to subpart O requirements pursuant to the RIN2 
Final Rule will not disturb the pertinent requirements of that 
subpart described above.
---------------------------------------------------------------------------

Gas Distribution Pipelines
    Distribution pipelines are subject to select part 192, subpart M 
maintenance requirements. Section 192.721 requires operators to patrol 
distribution mains at frequencies that consider the severity of the 
conditions that would cause failure or leakage, and the consequent 
hazard to public safety. Distribution mains subject to physical 
movement or external loading that could fail or leak must be patrolled 
at least twice each calendar year if located outside of business 
districts, and at least four times every calendar year if located 
within business districts. Distribution leakage survey requirements are 
defined in Sec.  192.723. In business districts, operators must conduct 
leakage surveys of distribution pipelines with leak detection equipment 
at least once every calendar year. These surveys must include testing 
the atmosphere in utility manholes, at cracks in the pavement and 
sidewalks, and at other locations, providing opportunities to find 
leaks. Outside of business districts, operators must perform leakage 
surveys using leak detection equipment as frequently as necessary, but 
not less than once every 5 calendar years. Gas distribution operators 
are subject to repair requirements for hazardous leaks at Sec.  
192.703, but that requirement provides no specific guidance on repair 
timelines and fails to mention environmental risks.
    The distribution IM program (DIMP) regulations in subpart P require 
distribution pipeline operators to identify, prioritize, assess, 
evaluate, repair, and validate the integrity of gas distribution 
pipelines that have the potential to cause injury or death in the event 
of a leak or failure. Section 192.1007 requires operators to 
demonstrate an understanding of their gas distribution systems based on 
reasonably available information. Operators then must apply the 
knowledge acquired through reasonably available information to identify 
threats to the integrity of their gas distribution systems. Threats can 
include a variety of phenomena: corrosion, excavation damage, vehicular 
strikes, poorly fitting connections, and other threats. Operators must 
evaluate and rank the risk to their systems from those threats, and 
then identify and implement measures to address those risks. DIMP 
regulations require operators to periodically (at least once every 5 
years) evaluate the threats, risks, and results of the performance 
measures to gauge the effectiveness of their DIMPs in controlling each 
threat. And Sec.  192.1007(d) explicitly requires distribution pipeline 
operators to either repair all leaks when found or have an ``effective 
leak management program.'' However, subpart P prescribes few specific 
requirements for those leak management programs or criteria for 
determining their effectiveness, requiring a distribution pipeline 
operator only to monitor (as a performance measure for evaluating a 
DIMP), the number of leaks it eliminates or repairs; to categorize such 
leaks by cause, material; to determine whether they are ``hazardous''; 
and to report such measures annually to PHMSA. Indeed, the preamble to 
the 2009 final rule codifying subpart P merely suggested that each 
operator ``should develop a program based on their knowledge of their 
pipeline system'' with the GPTC Guide identified as an aid in 
developing such a program.\133\
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    \133\ PHMSA, ``Pipeline Safety: Integrity Management for Gas 
Distribution Pipelines--Final Rule,'' 74 FR 63905, 63917 (Dec 4, 
2009). PHMSA is undertaking a complementary rulemaking under RIN 
2137-AF53 (``Pipeline Safety: Safety of Gas Distribution Pipelines 
and Other Pipeline Safety Initiatives'') responding to congressional 
mandates in title II of The PIPES Act of 2020 directing PHMSA to, 
among other things, amend its subpart P distribution IM program 
requirements. PHMSA expects that the leak detection, grading, and 
repair requirements for gas distribution pipelines proposed herein 
would reinforce any changes to subpart P proposed in that 
rulemaking.

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[[Page 31909]]

2. Shortcomings of Current PHMSA Regulations in Addressing 
Unintentional Releases From Gas Pipelines
    PHMSA regulations pertinent to leaks from gas pipelines focus on 
risks to public safety posed by ignition of instantaneous, large-volume 
releases or accumulated gas from gas pipeline facilities--an approach 
that is vital for protecting public safety but that foregoes 
opportunities to address environmental harms, including methane 
emissions' contribution to climate change. This approach has proven 
unsuccessful in timely identification and remediation of leaks that can 
have a substantial impact on the environment or even evolve into 
incidents posing catastrophic risks to public safety.
    As explained above, part 192 subpart M maintenance requirements 
contain only a single repair requirement specific to leaks, which is 
applicable only to some part 192-regulated gas gathering, transmission, 
and distribution pipelines: Sec.  192.703(c)'s requirement that 
``hazardous leaks'' be repaired ``promptly.'' However, the term 
``hazardous leak'' is nowhere defined in subpart M. Rather, what other 
limited evidence there is in PHMSA regulations elaborating on the 
meaning of ``hazardous leak'' pertains either to entirely different 
elements of part 192 (specifically, the Sec.  192.1001 definition of 
``hazardous leak'' within DIMP requirements in subpart P) or part 191 
reporting requirements.\134\ These regulatory provisions both describe 
``hazardous leak'' with respect to potential or present risks to public 
safety; they are silent regarding risks to the environment.
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    \134\ See, e.g., PHMSA, Form F7100.1-1 Instructions (May 2021) 
(defining hazardous leaks as those representing an ``existing or 
probable hazard to persons or property and requires immediate repair 
or continuous action until the conditions are no longer 
hazardous''). The instructions for annual report forms for other gas 
pipeline facilities contain similar language.
---------------------------------------------------------------------------

    Similarly, subpart M does not elaborate on the requirement that all 
hazardous leaks be repaired ``promptly.'' Section 192.711 allows 
operators to repair hazardous leaks and other conditions as soon as 
feasible for non-IM repairs, and as prescribed by Sec.  192.933(d) for 
IM repairs. If a permanent repair is infeasible, Sec.  192.711 merely 
requires that any temporary measure addresses public safety, again 
excluding the environment from explicit consideration.
    Part 192 nowhere specifies remote or continuous monitoring for 
pipeline leaks apart from a recent limited requirement pertaining to 
detection of ruptures (rather than leaks) on certain new gas 
transmission pipelines with rupture mitigation valves.\135\ Frequencies 
of leakage survey (Sec.  192.706) and patrol (Sec.  192.705) 
requirements are generally keyed to location and the likelihood of 
nearby people--proxies for risks to public safety but not the 
environment. Consequently, the majority of part 192-regulated gas 
transmission and some part 192-regulated, onshore gathering mileage in 
the United States (in particular, Types A and B gathering pipelines in 
more populated areas, and a minority of Type C lines \136\) need only 
have annual leakage surveys, with as long as 15 months between surveys. 
The default leak detection survey periodicity for gas distribution 
pipelines outside of business districts is only once every 5 years. 
Similarly, PHMSA regulations at subpart M allow gas transmission and 
select part 192-regulated gathering pipeline mileage to have right-of-
way patrols only once a year, if at all. Finally, patrols on gas 
distribution pipelines inside business districts are required twice a 
year.
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    \135\ PHMSA, ``Pipeline Safety: Requirement of Valve 
Installation and Minimum Rupture Detection Standards--Final Rule,'' 
87 FR 20940, 20985 (Apr. 8, 2022) (introducing a new Sec.  192.636).
    \136\ Only ca. 20,000 miles of the ca. 91,000 miles of Type C 
gas gathering pipelines are subject to Sec.  192.706 leakage survey 
requirements. PHMSA, Doc. No. PHMSA-2011-0023-0488, ``Regulatory 
Impact Analysis for Gas Gathering Final Rule'' at 11, 15 (Nov. 
2021).
---------------------------------------------------------------------------

    Subpart M maintenance requirements governing the use of leak 
detection equipment also reflect the same historical focus on acute 
public safety risks. Subpart M regulations are silent on specific 
technologies or equipment operators should employ in their leak 
detection surveys. For example, leakage surveys on gas distribution 
lines, certain regulated gathering lines, and un-odorized transmission 
pipelines in Class 3 and Class 4 locations must be performed with leak 
detection equipment--but part 192 neither requires particular 
technologies, nor establishes performance standards for leak detection 
equipment. Leakage surveys on other gas transmission pipelines (e.g., 
odorized lines and all pipelines in Class 1 and Class 2 locations) and 
patrols of pipeline rights-of-way can rely entirely on human senses 
such as smell or sight, which are imprecise and substantially limited 
in their effectiveness. Evidence of a leak detectible by human senses 
includes dead vegetation caused by natural gas displacing oxygen in the 
soil, blowing soil, bubbling water, or noise. However, it may take a 
long time for evidence of a gas leak on vegetation to appear visibly 
from the air. Further, the reliability of vegetation surveys is 
inconsistent and depends heavily on soil and climate conditions, the 
characteristics of the vegetation, the time of year, and other factors. 
For example, the impacts of gas leaks on vegetation may not be visible 
during seasonal or climate conditions that produce dead vegetation, and 
in some soil conditions gas can temporarily increase vegetation growth. 
Finally, vegetation surveys are ineffective in areas with no or sparse 
vegetation, such as paved areas, particularly rocky areas, or deserts. 
PHMSA is not aware of research on the effectiveness of vegetation 
surveys versus instrumented surveys in general, however operators who 
begin performing instrumented surveys (such as the aerial survey 
examples described in section II.D.4) generally report more leaks 
discovered using instrumented surveys.
    Additionally, PHMSA's IM regulations do not require identification 
and remediation of all leaks. PHMSA's IM regulations apply to about 7 
percent of gas transmission pipelines.\137\ And no part 192-regulated 
gathering pipelines (even Types A and C pipelines with operating 
characteristics and threats to public safety and the environment 
comparable to transmission lines) \138\ are subject to any IM 
requirements. IM requirements also reflect a historical focus on 
identifying, preventing, and remediating risks to public safety from 
large-volume, instantaneous releases or accumulated gas rather than 
environmental harms. While the gas transmission IM regulations at 
subpart O oblige some transmission operators to find and eliminate 
pipeline anomalies posing risks to public safety, those regulations do 
not require repair of all leaks discovered and allow for substantial 
delay in the evaluation and subsequent repair of leaks that operators

[[Page 31910]]

(largely at their discretion) consider not to pose acute public safety 
risks. DIMP regulations require gas distribution pipeline operators to 
have an ``effective leak management program,'' but those regulations 
provide few standards regarding what constitutes an ``effective'' 
program and can instead give considerable deference to an operator's 
discretion regarding which leaks are repaired and when. Further, 
neither subparts O nor P require operator IM plans to consider 
replacement or remediation as a preventative or mitigative measure for 
pipe materials known to leak, despite data demonstrating that cast 
iron, wrought iron, unprotected steel, and certain plastic pipelines 
are more susceptible to leaks and other losses of pipeline integrity. 
PHMSA's IM regulations are also not designed to address leaks with low 
release rates that persist for a long period of time, which can make 
significant contributions to climate change.
---------------------------------------------------------------------------

    \137\ The effectiveness of its IM regulations for gas 
transmission pipelines at subpart O relies on operators' 
identification that those requirements apply--which is not a given. 
See NTSB, Pipeline Accident Brief 13-01, ``Rupture of Florida Gas 
Transmission Pipeline and Release of Natural Gas'' (Aug. 13, 2013) 
(finding that a gas transmission pipeline operator's exclusion of a 
segment from its IM plan due to mischaracterization of a Class 1 
location contributed to a subsequent rupture).
    \138\ See Gas Gathering Final Rule, 87 FR at 6367-68, 63278-79 
and 63282-84.
---------------------------------------------------------------------------

    PHMSA part 191 reporting requirements also reflect a narrow focus 
on public safety risks rather than environmental harms such as the 
contribution of methane leaks to climate change, or environmental 
degradation from the release of other flammable, toxic or corrosive 
gases. Incident reporting requirements are expressed in terms of 
personal injury, commercial harm, property damage, or minimum release 
volumes that are far too high (3 MMCF) to capture any but the largest 
unintentional leaks from pipeline facilities--corresponding to a 
volumetric release rate of 340 cubic feet per hour (CFH) or more over a 
one-year period. Although annual reports submitted to PHMSA contain 
information on all leaks repaired each year, the instructions for those 
annual reports explicitly discourage reporting of leaks that can be 
eliminated by ``lubrication, adjustment or tightening'' on the narrow 
presumption that such releases were not necessarily hazardous from a 
public safety perspective. Operators are also not required to submit in 
their annual reports the total number of leaks--of any type--detected 
in the reporting period; the number of outstanding unrepaired leaks 
from year-to-year; or estimated emission volumes from any category of 
detected leaks.
    Finally, the exclusion of all gas gathering pipelines from NPMS 
reporting requirements inhibits PHMSA, State regulators, operators, and 
members of the public from knowing the location and operating 
characteristics of pipelines. Such knowledge would help identify and 
remediate leaks and avoid excavation damage. Although all part 192-
regulated gathering pipelines are subject to damage prevention 
requirements of Sec.  192.614, those requirements are not reinforced by 
the NPMS requirements identifying the precise location of pipeline 
infrastructure.
3. Real-World Consequences of Delayed Repair and Prolonged Releases 
From Leaks on Gas Pipelines
    The shortcomings of existing regulations pertaining to leak 
detection and repair described above are not abstract risks; operators 
currently allow leaks from gas pipelines to continue emitting methane 
and other gases for extended periods of time, thereby threatening the 
environment as well as public safety and human health.
    Infrequent leak detection and patrol periodicities provide extended 
time intervals within which leaks can develop and worsen, thereby 
resulting in prolonged methane and other emissions to the atmosphere. 
Infrequent leak detection and patrol periodicities also entail 
increased public safety risks. Specifically, PHMSA's regulations have 
long recognized the safety risk associated with potential ignition of 
leaks, as evidenced by heightened leak surveying and maintenance 
requirements throughout part 192 for pipelines located in areas where 
buildings intended for human occupancy are more prevalent (Class 3 or 4 
locations) as well as requirements to prevent the accumulation of gas 
in confined spaces (see, e.g., Sec. Sec.  192.167(c)(2), 192.353(c), 
192.355(b)(2), and 192.361(e)(3)). But leaks on gas pipelines that are 
not associated with potential ignition of leaks also entail public 
safety risks. Leaks of toxic or corrosive gases from part 192-regulated 
pipeline facilities can have serious public safety consequences. And 
leaks of any type can degrade into catastrophic failures--sometimes 
referred to as the ``leak-before-break'' concept.\139\ Additionally, 
the absence of baseline leak detection equipment technology 
requirements for conducting leakage surveys can also inhibit timely 
opportunities to identify, evaluate, and remediate leaks. The absence 
(in subparts M, O, and P) of repair criteria and mandatory repair 
schedules for all leaks compounds the delays and methodological 
shortcomings in identifying leaks. And PHMSA's limited reporting 
requirements for leaks from all types of gas pipeline facilities can 
complicate its ability to identify systemic pipeline integrity issues 
or support enforcement actions against specific operators. Lastly, the 
exemption of all gas gathering pipeline facilities from NPMS reporting 
requirements inhibits timely leak detection and introduces heightened 
vulnerability to a principal mechanism (excavation damage) for loss of 
pipeline integrity.
---------------------------------------------------------------------------

    \139\ See, e.g., Wilkowski, ``Leak-Before-Break, What Does It 
Really Mean?'' 122 Journal of Pressure Vessel Technology 267 (Aug. 
2000); Zhang, et al., ``Paper: Preventive Leak Detection for High 
Pressure Gas Transmission Networks,'' AAAI 2017 (2017); see also 
GPTC Guide appendix G-192-11 table 3c, recommending that grade 3 
leaks be re-evaluated within 15 months or during the next required 
leakage survey.
---------------------------------------------------------------------------

    PHMSA further estimates that, due to those limitations in its 
regulatory regime, thousands of leaks persist across part 192-regulated 
gas pipelines. With respect to gas distribution pipelines, PHMSA annual 
report data between 2010 and 2021 yields roughly the same per-mile, 
nationwide averages of repairs of all leaks (0.225 leaks repaired/mile 
in 2010 and 0.230 in 2021) and repairs of hazardous leaks (0.089 in 
2010 and 0.086 in 2021). PHMSA assumes that the average per-mile rate 
at which new leaks are created (controlled for material type) remains 
constant, suggesting either that operators may not be reporting to 
PHMSA a significant number of leak repairs on their gas distribution 
pipelines; operators are not discovering or repairing a significant 
number of leaks on their gas distribution pipelines; or existing 
regulatory requirements and operator repair practices have not yielded 
improvements in reducing the frequency of leak repairs (and perhaps 
have failed to yield improvements in leak identification) on gas 
distribution pipelines for nearly a decade. PHMSA incident report data 
for gas distribution pipelines shows that distribution system operators 
reported only 377 incident reports identified as leaks (rather than 
ruptures or mechanical punctures) during the entire period from 2010 
through 2020. This represents a miniscule percentage of the 510,224 
leak repairs reported on operators' annual reports in 2020 alone, a 
figure which does not include leaks that are not scheduled for repair 
at all. Forty-five percent of these reported leaks were attributable to 
causes that progressed over time (e.g., corrosion failure, equipment 
failure, and material failure), which may have been discovered earlier 
through more frequent leakage surveys, patrols, and repair practices. 
As described later in this section, evidence that leaks that are large 
in release volume or hazardous to public safety are not reliably 
detected or repaired is further supported by available state-

[[Page 31911]]

level information shows persistent backlogs of grade 3 leaks and 
research with advanced leak detection methods, which suggests that 
operators may not reliably detect releases with large volumes or that 
are hazardous to public safety.
    Data from States employing the three-tiered GPTC Guide leak grading 
framework (discussed in section II.E.) for gas distribution pipeline 
facilities demonstrates that most leaks on distribution main and 
service pipelines that are identified by operators are not subject to 
PHMSA repair requirements as hazardous leaks, and can persist for 
extended periods before repair. By way of example, the 2020 Pipeline 
Safety Performance Measures Report from New York State reports that out 
of 19,683 leaks on main and service pipelines discovered by 11 natural 
gas local distribution companies in 2019, 7,403 (37.6%) were grade 1 
leaks that approximate to ``hazardous leaks'' under PHMSA repair 
requirements in Sec.  192.703(c), while an additional 5,468 (27.8%) 
were grade 2 leaks, and 5,768 (29.3%) were grade 3 leaks using New York 
State requirements similar to the GPTC Guide criteria.\140\ New York 
State has adopted repair deadlines mirroring those in the GPTC Guide 
for grade 2 leaks (12 months or 6 months, depending on potential 
hazard, see 16 NYCRR 255.813-255.815). However, neither the GPTC Guide 
nor New York regulations (as of October 2022) require repair of grade 3 
leaks, resulting in a backlog of almost 10,000 outstanding unrepaired 
leaks in 2020.\141\ Each of these unrepaired leaks will continue to 
release methane (or other gases) to atmosphere until remediated, and 
each could increase in size between patrols or leakage surveys. 
Minority populations and other disadvantaged communities often bear the 
brunt of unrepaired leaks on those gas distribution systems.\142\ The 
IM regulations at subpart P have proven insufficient to prevent leaks, 
as all the gas distribution pipelines, including those in the New York 
data described above, had been subject to DIMP regulations.
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    \140\ State of New York Department of Public Service, Case 21-G-
0165, ``2020 Pipeline Safety Performance Measures Report'' (June 17, 
2021), https://www3.dps.ny.gov/W/PSCWeb.nsf/All/9DBA66C148A1310985257B2600750639?OpenDocument. Note that New York 
leak classification requirements use the term ``types'' rather than 
``grades,'' however they are conceptually identical.
    \141\ State of New York Department of Public Service, Case 21-G-
0165, ``2020 Pipeline Safety Performance Measures Report'' at 
Appendix K (June 17, 2021), https://www3.dps.ny.gov/W/PSCWeb.nsf/All/9DBA66C148A1310985257B2600750639?OpenDocument.
    \142\ Luna et al., ``An Environmental Justice Analysis of 
Distribution-Level Natural Gas Leaks in Massachusetts, USA,'' 162 
Energy Policy 112778 (2022). This study of the distribution of gas 
leaks reported to the Massachusetts Department of Public Utilities 
found consistently higher densities of unrepaired leaks in the homes 
of people of color, lower income persons, renters, adults with lower 
levels of education, and limited English-speaking households. These 
same groups were more likely to experience slower repair times and 
significantly older unrepaired leaks.
---------------------------------------------------------------------------

    The number of leaks from gas transmission pipelines are also 
significant. A review of PHMSA incident data yields that over 500 
(roughly 40%) of the 1,300 incidents reported by gas transmission 
operators between 2010 and 2020 involved hazardous leaks.\143\ PHMSA's 
IM regulations at subpart O do not ensure that pipeline operators 
prevent such leaks. Of the over 500 leaks reported as incidents on gas 
transmission pipelines between 2010-2020, nearly a quarter of those 
incidents occurred on gas transmission pipelines subject to subpart O 
requirements. Further, incident reports on gas transmission pipelines 
show that many were either identified during leakage surveys or patrols 
or were attributed to causes that could have degraded over time. PHMSA 
therefore expects that more frequent patrols and leakage surveys and 
prompt remediation would result in earlier detection and potential 
avoidance of leak degradation that would lead to incidents.
---------------------------------------------------------------------------

    \143\ This calculation is based on a review of gas transmission 
pipeline incident reports, excluding incidents attributed to other 
causes such as ``mechanical puncture,'' ``rupture'' or ``other.''
---------------------------------------------------------------------------

    Annual report data similarly suggests a large number of leaks on 
gas transmission pipelines and the potential value of enhanced leak 
detection and repair requirements for promptly identifying and 
remediating those leaks. In annual reports submitted between 2012-2021, 
operators of gas transmission pipelines reported repairing an average 
of 13,600 leaks repaired per year across the 302,000 miles of gas 
transmission pipelines nationwide. But part 191 requires annual 
reporting of only the number of leaks repaired--not all detected leaks 
(even hazardous leaks detected but not repaired). In addition, part 192 
does not provide clear timelines for ``prompt'' repair of hazardous 
leaks, much less any timeline for other leaks. Even if unreported, non-
hazardous leaks occurred on gas transmission pipelines at just a 
fraction of the average, per-mile rate of hazardous leak repairs noted 
in annual reports over the last decade, there would be a significant 
number of additional, unreported leaks on gas transmission pipelines 
each year. Those unreported leaks would generally not be subject to 
prescribed repair timelines under existing PHMSA regulations. Although 
some of those leaks could be identified and corrected in a timely 
manner pursuant to PHMSA's IM regulations at subpart O, the limited 
application of those requirements (only transmission pipelines in HCAs) 
and the significant discretion given to operators in designing and 
executing IM plans do not guarantee any such leaks would be identified 
and remediated promptly.
    PHMSA similarly understands that its existing regulations tolerate 
the persistence of numerous leaks on part 192-regulated gas gathering 
pipelines. Data from incidents on Types A and B gas gathering pipelines 
across 2010-2020 yields an average, per-mile rate of incidents--83 
incidents on 11,542 miles of pipeline (0.0072 incidents/mile)--nearly 
double that of gas transmission pipelines (0.00435 incidents/mile) over 
the same period. Further, leaks are a more frequent cause of incidents 
on Types A and B gas gathering pipelines than for gas transmission 
pipelines--operators attributed nearly 80% of the incidents reported on 
Types A and B gathering pipelines to leaks. And PHMSA understands from 
reviewing incident reports for Types A and B gathering pipelines that 
many of those incidents could have been avoided or mitigated by more 
timely detection and repair. Annual report data for Types A and B 
gathering pipelines tells a similar story. In 2020 annual reports, 
Types A and B gathering operators reported 1,574 hazardous leak repairs 
on 298,795 miles of onshore gas transmission pipelines (5.3 leaks per 
1,000 miles) and 153 hazardous leak repairs on 11,542 miles of Type A 
and Type B regulated onshore gas gathering pipelines (13.3 leaks per 
1,000 miles). If the number of hazardous leak repairs corresponds to 
the total number of hazardous leaks identified, Types A and B gathering 
pipelines would have an average, per-mile rate of hazardous leaks more 
than twice that of gas transmission pipelines. Similar to the 
discussion above regarding distribution and transmission lines, the 
annual report-derived values understate the total number of leaks on 
Types A and B gathering lines. Therefore, the total number of leaks on 
Types A and B gathering lines not subject to any meaningful Federal 
repair requirements is likely even higher. Furthermore, the number and 
persistence of leaks on Type C pipelines are likely to be higher than 
on Types A and B gas gathering pipelines because Type C gathering 
pipelines have historically avoided any meaningful

[[Page 31912]]

State or Federal reporting or design requirements.\144\
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    \144\ See, e.g., PHMSA, Doc. No. PHMSA-2011-0023-0504, 
``Response to Petition for Reconsideration of the Gas Gathering 
Final Rule'' at 3 (Apr. 1, 2022).
---------------------------------------------------------------------------

    The number and persistence of leaks on gas distribution, 
transmission, and gathering pipelines tolerated by PHMSA regulations 
entail considerable risks to public safety.\145\ Each of those leaks 
discussed above that were or became incidents reported pursuant to part 
191 involved significant public safety consequences: specifically, one 
or more of death, personal injury necessitating in-patient 
hospitalization, property damage of $122,000 or more (excluding the 
value of the gas itself), or 3 MMCF or more gas lost. Similarly, each 
of the hazardous leaks observed on gas pipelines under existing PHMSA 
regulations are a hazard with respect to public safety. Since leaks in 
pressurized systems can over time degrade into catastrophic failures, 
even those leaks that have not yet been reported as incidents or 
otherwise designated as hazardous in that they do not involve an 
existing or imminent risk of ignition can nevertheless give rise to 
such risk if not repaired.
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    \145\ PHMSA discusses in this section only direct public safety 
consequences of leaks; however (as explained in section II.D.3), 
leaks and other releases from gas pipelines can also have second-
order public safety impacts resulting from climate change-induced 
natural force damage and equipment malfunction.
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    Lastly, any leak from gas gathering pipelines entails unique public 
safety risks. Natural gas gathering pipelines are often located in the 
vicinity of socially vulnerable populations.\146\ Additionally, 
unprocessed natural gas within gathering pipelines typically contains 
significant quantities of volatile organic compounds (VOCs) and 
hazardous air pollutants (HAPs) such as benzene (a known carcinogen). 
As discussed in further detail in the Preliminary RIA, VOCs and HAPs 
pose risks from long-term adverse health effects. VOC emissions are 
precursors to ozone, and to a lesser extent fine particulate matter 
(PM2.5). Both ambient ozone and PM2.5 are 
associated with adverse health effects, including respiratory 
morbidity, such as asthma attacks, hospital and emergency department 
visits, lost school days, and premature respiratory mortality. HAPs 
contained in unprocessed natural gas includes several substances that 
are known or suspected carcinogens, including but not limited to 
benzene, formaldehyde, toluene, xylenes, and ethylbenzene. Benzene and 
formaldehyde are known human carcinogens, and ethylbenzene has been 
identified as possibly carcinogenic in humans. Chronic (long-term) 
inhalation of benzene can result in several adverse noncancer health 
effects including arrested development of blood cells, anemia, 
leukopenia, thrombocytopenia, and aplastic anemia, and acute (short-
term) exposure to benzene vapors has been reported to cause negative 
respiratory effects. Formaldehyde inhalation exposure also causes a 
range of noncancer health effects including irritation of the nose, 
eyes, and throat, and repeated exposures cause respiratory tract 
irritation, chronic bronchitis, and nasal epithelial lesions. There is 
evidence that formaldehyde may also increase the risk of asthma and 
chronic bronchitis in children. Inhalation of toluene, mixed xylenes, 
and ethylbenzene can have neurological, respiratory, and 
gastrointestinal effects, among others, with chronic exposure to 
toluene potentially leading to developmental effects such as central 
nervous system dysfunction, attention deficits, and other anomalies. 
Further, corrosives entrained in the unprocessed natural gas can 
accelerate corrosion in the vicinity of leaks, thereby increasing the 
risk of a catastrophic failure. Recent incident data on Types A and B 
gas gathering pipelines similarly underscores the unique risks to 
public safety posed by the exemption of any part 192-regulated gas 
gathering pipelines from PHMSA's NPMS reporting requirements. The 
average, per-mile rate of incidents due to excavation damage reported 
to PHMSA between 2010 and 2020 on Types A and B gathering pipelines was 
comparable to that on distribution pipelines (0.023 and 0.027 annual 
incidents per 1,000 miles, respectively); further, insufficient 
locating practices have been reported to PHMSA as a contributing factor 
in those incidents.
---------------------------------------------------------------------------

    \146\ Emanuel et al., ``Natural Gas Gathering and Transmission 
Pipelines and Social Vulnerability in the United States,'' 5 
GeoHealth (June 2021) (concluding that natural gas gathering and 
transmission infrastructure is disproportionately sited in socially-
vulnerable communities).
---------------------------------------------------------------------------

    Aside from the public safety risks discussed above, leaks from gas 
distribution, transmission, and gathering pipelines are also a 
significant contributor to climate change. As discussed in section 
II.C.2 of this NPRM, current methane emissions data identifies leaks 
across line pipe alone on U.S. natural gas distribution, transmission, 
and gathering as a significant contributor (the GHGI estimates nearly 
328.9 kt CH4 in 2019) to U.S. methane emissions. But current 
methane emissions estimates could materially understate actual methane 
emissions. GHGRP reporting requirements do not capture all gas pipeline 
mileage subject to PHMSA's regulations at parts 191 and 192, 
introducing uncertainty into whether national average methane emissions 
estimates derived from such reports may accurately be extrapolated to 
all PHMSA-regulated gas pipelines. Additionally, recent evidence from 
aerial surveys of a small (7,500 square kilometer) swath of the Permian 
basin \147\ found leaks from natural gas gathering pipelines in the 
Permian basin to be a larger source of methane emissions than would be 
calculated using the national average in the GHGI.\148\ A series of 
two-week aerial surveys conducted in the fall of 2019, summer of 2021, 
and fall of 2021 conducted for the Environmental Defense Fund (EDF)'s 
Permian Methane Analysis Project observed between 50 and 350 leaks 
attributed to gas gathering line pipe, of which roughly half are likely 
attributable to part 192-regulated gathering line pipe. PHMSA made this 
assessment by comparing the leak coordinates for gathering line pipe 
within the raw data of EDF's Permian Methane Analysis Project \149\ to 
geospatial data for specific gathering pipelines downloaded from the 
Texas Railroad Commission (TRRC) website.\150\ PHMSA then reviewed the 
TRRC's database of attributes of those gathering pipelines to determine 
diameter, using that metric to determine whether an observed leak was 
on a part-192 regulated gathering pipeline. The leaks identified in 
these aerial surveys, moreover, were not de minimis: the average leak 
rate observed by EDF was 273 kg CH4/hour, correlating to 
roughly a metric ton of methane emitted to atmosphere every five days. 
Even this limited Permian Basin data could under-report the number and 
scale of leaks from methane emissions from gas gathering pipelines if 
projected

[[Page 31913]]

nationwide.\151\ Many of the gathering pipelines in the Permian basin 
are relatively new pipelines, while older gas gathering infrastructure 
in other production regions may leak at higher rates.
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    \147\ The entire Permian basin covers approximately 86,000 
square miles--more than 220,000 square kilometers.
    \148\ See Yu et al., ``Methane Emissions from Natural Gas 
Gathering Pipelines in the Permian Basin,'' Environ. Sci. Technol. 
Lett. (Nov. 8, 2022) (Yu Study) (``The EF [(emissions factor)] 
derived from each of the four aerial surveys is more than an order 
of magnitude higher than the EPA's published values [for national 
average emissions].''). The emissions factors calculated from this 
study were also ``4-13 times higher than the highest estimate 
derived from a published ground-based survey of gathering lines.''
    \149\ See EDF, Permian Methane Analysis Project, https://permianmap.org/ (last accessed July 20, 2022).
    \150\ https://rrc.texas.gov/oil-and-gas/publications-and-notices/maps/ (last accessed July 25, 2022).
    \151\ The Yu Study acknowledged that its data may also be 
underestimating emissions from gathering pipelines. The authors 
conservatively excluded any emissions sources in areas of co-located 
gathering and transmission pipelines where the source could not be 
definitively attributed, although the authors noted that it would be 
reasonable to assume at least some of those sources were from 
gathering pipelines. See Yu et al.
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4. Regulatory Requirements Lag Commercially Available, Advanced Leak 
Detection Technologies
    As explained above in section D.1, PHMSA regulations prescribe 
requirements for identifying leaks--leakage surveys and rights of way 
patrols--directed principally toward risks to public safety (from 
ignition of instantaneous, large-volume releases or accumulated gas) 
and not toward environmental harm that even small leaks can cause. 
Consistent with that historical approach, PHMSA regulations permit 
reliance on non-instrumented leak detection methods such as smell or 
visual surveys of gas transmission pipeline infrastructure and rights 
of way that are more appropriate for discovering ruptures or 
accumulated gas than smaller leaks. When leak detection equipment is 
required, PHMSA regulations specify neither particular leak detection 
technologies nor minimum performance standards for detection of gas 
concentration by leak detection equipment.
    These shortcomings in PHMSA's regulatory regime allow operators to 
rely on inadequate or ineffective leak detection equipment and 
practices, rather than encouraging use of commercially available, 
advanced leak detection technologies and practices appropriate to 
different gases transported by gas pipeline facility subject to part 
192. Many of these technologies and practices were discussed by PHMSA, 
industry and academic research organizations, and vendors within a 
virtual public meeting on advanced methane leak detection technology 
and practices hosted by PHMSA on May 5-6, 2021 (2021 Public 
Meeting).\152\ PHMSA staff also attended the Methane Detection 
Technology Workshop hosted by EPA on August 23-24, 2021 (2021 EPA 
Methane Detection Technology Workshop).153 154 155 156 
Presenters at these meetings described how innovations in equipment 
sensitivity, analytics, automation, and survey speed of leak detection 
services could increase the effectiveness and decrease the cost of 
detecting gas releases from oil and gas facilities.
---------------------------------------------------------------------------

    \152\ Recordings, transcripts, and slides from the 2021 Public 
Meeting are available at the meeting web page at https://primis.phmsa.dot.gov/meetings/MtgHome.mtg?mtg=152. A number of 
entities submitted written comments before and after the meeting 
that are available in the rulemaking docket at Doc. No. PHMSA-2021-
0039.
    \153\ Recordings are available at the EPA meeting web page at: 
https://www.epa.gov/controlling-air-pollution-oil-and-natural-gas-
industry/epa-methane-detection-technology-
workshop#:~:text=Natural%20Gas%20Industry-
,EPA%20Methane%20Detection%20Technology%20Workshop%20%2D%2D%20August%
2023%20and%2024,oil%20and%20natural%20gas%20industry (last accessed 
July 20, 2022).
    \154\ See ``Attachment 1: Summary Report Methane Detection 
Technology Workshop'' of ``Background Technical Support Document for 
the Proposed New Source Performance Standards (NSPS) and Emissions 
Guidelines (EG)'' at https://www.regulations.gov/ Docket ID No. EPA-
HQ-OAR-2021-0317-0166.
    \155\ See ``EPA's Methane Detection Technology Virtual Workshop. 
August 23-24, 2021. Audio'', ``Transcripts'', and ``Presentations'' 
at https://www.regulations.gov/ Docket ID No. EPA-HQ-OAR-2021-0317-
0183, EPA-HQ-OAR-2021-0317-0181, and EPA-HQ-OAR-2021-0317-0182 
respectively.
    \156\ See ``Controlling Air Pollution from the Oil and Natural 
Gas industry. EPA Methane Detection Technology Workshop. August 23 
and 24, 2021'' https://www.regulations.gov/ Docket ID No. EPA-HQ-
OAR-2021-0317-0183.
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    At the 2021 Public Meeting, EDF presented a set of recommended 
elements for an advanced methane leak detection system, including (1) 
leak detection equipment with a parts-per-billion level of sensitivity 
\157\ and the ability to capture other data for use in an algorithm to 
understand the size and location of leaks; (2) a defined deployment 
strategy or work practice to ensure that accurate data is being 
collected; and (3) comprehensive data collection on topics such as leak 
location, estimated leak flow rate or gas emission rate, a coverage map 
showing which areas were successfully surveyed and which areas were 
not, and a summary or cumulative loss estimate for the total area 
surveyed. AGA observed in their remarks at the 2021 Public Meeting and 
AGA et al.\158\ in their written comments that most currently available 
leak detection technologies are focused on identifying indications of 
methane leaks in the air (i.e., gas concentration) rather than 
measuring the rate of leakage from a component. AGA et al. 
characterized methane concentration as a more appropriate metric for 
evaluating the public safety risks from explosion than for estimating 
the amount of methane going to atmosphere.
---------------------------------------------------------------------------

    \157\ EDF commented that parts-per-billion detection is 
important in this effort in light of the potential for hidden 
underground leaks, where only a small volume of gas may migrate 
through the pavement despite a significant leak buried under the 
street.
    \158\ The American Gas Association (AGA), API, American Public 
Gas Association, GPA Midstream Association (GPA), and Interstate 
Natural Gas Association of America submitted joint comments (Doc. 
No. PHMSA-2021-0039-0008) to the rulemaking docket after the 2021 
Public Meeting. Throughout this NPRM, references to ``AGA et al.'' 
refer to those joint comments.
---------------------------------------------------------------------------

    Several stakeholders at the 2021 Public Meeting emphasized the 
importance of flexibility in PHMSA's consideration of advanced leak 
detection standards, recommending that PHMSA assess the suite of leak 
detection technologies that are currently commercially available and 
introduce requirements that promote continued development of advanced 
technologies. EDF noted that it was essential that PHMSA set advanced 
methane leak detection standards that ensure an ongoing process for 
continuous technology improvement, recommending that PHMSA set a floor, 
not a ceiling, to create a space in Federal standards to push for the 
development of new ideas and improvements to technology over time for 
future incorporation. AGA et al. also suggested that applying 
prescriptive regulations could potentially limit the development of 
different technologies and innovations, stating that providing 
operators with flexibility can create opportunities and incentives for 
developing new technologies and innovations in leak detection and 
measurement. Similarly, the Pipeline Safety Trust (PST) stated that 
performance-based regulations for advanced leak detection (ALD) and 
methane reduction should use the capabilities of commercially available 
ALD technologies as a starting point, but that the ALD performance 
standards should change as commercially available technologies develop.
    AGA et al. emphasized the value of leak data analysis in lieu of 
requirements that operators use specific advanced leak detection 
technologies. AGA et al. observed that studies across the gas industry 
supply chain show that a majority of emissions come from a small number 
of high-emitting leaks, and thus leak data analysis enables operators 
to make substantial inroads on reducing methane emission by identifying 
and prioritizing repair of the highest-emitting leaks. AGA et al. also 
urged PHMSA to consider the affordability of any new regulatory 
requirements and suggested that in some situations, a simpler, less 
costly technology or practice may achieve safety and environmental 
goals more successfully than a newer technology.
    Notable commercially available, advanced leak detection 
technologies

[[Page 31914]]

and practices \159\ are described briefly below.
---------------------------------------------------------------------------

    \159\ PHMSA acknowledges that much of the discussion of advanced 
leak detection technologies and practices in this section is 
presented in terms of advanced methane leak detection technologies 
for use in connection with natural gas pipeline facilities, rather 
than leak detection technologies and practices for other gases whose 
transportation within pipeline facilities is subject to part 192. 
However, many of the advanced leak detection technologies and 
practices for methane are comparable to the technologies and 
practices employed in connection with other gases.
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Hand-Held Leak Detection Equipment
    The most common method for instrumented leakage surveys (meaning a 
leakage survey performed using leak detection equipment) on natural gas 
pipelines consists of surveys along the pipeline right-of-way with 
handheld leak detection equipment. A surveyor typically uses a flame 
ionization detector (FID), infrared gas detector, optical gas imaging 
(OGI) device,) or other gas detector to sample gas above a buried 
pipeline, inside underground structures, and possibly in the soil. 
Handheld equipment is used to perform most leakage surveys, and any 
advanced leak detection solution that does not operate directly on or 
over the pipeline would still require confirmation of leak indications 
on the ground by operator personnel with handheld equipment. For 
aboveground or excavated leaks, gas detection instruments are often 
supplemented with a ``soap test'' that involves applying a soapy 
solution to the probable leak location. The location and size of the 
bubbles produced by escaping gas provides an indication of the exact 
location of the leak source and the relative size of the leak.
    Handheld devices have been a focus of research and development 
(R&D) by PHMSA, equipment manufacturers, and operators. Recent 
innovations available on the market, including highly sensitive 
handheld equipment and laser-based detectors capable of detecting gas 
at a distance, have improved the effectiveness, efficiency, and safety 
of traditional walking surveys. A walking survey can be effective at 
detecting pipeline leaks, assuming that the location of the pipeline is 
known, adequate equipment is used, and survey personnel follow 
procedures that ensure the pipeline and potential migration paths are 
properly surveyed, and there may not be an alternative to walking 
surveys in some environments with poor equipment access. The 
performance of leak detection equipment and procedures may vary 
depending on weather and soil conditions or other environmental 
factors. The GPTC Guide includes guidelines for performing leakage 
surveys.
    Walking surveys, however, tend to be expensive and time-consuming 
because they require significant personnel resources to execute. 
Effectiveness of even advanced handheld leak detection technologies can 
be reduced by poor operator training, inadequate survey procedures, or 
use of poorly maintained or uncalibrated equipment.
Automobile-Based Leak Detection Equipment
    Similar equipment used in walking surveys can be mounted on cars 
and trucks to allow efficient surveying of pipelines with adequate road 
access. The effectiveness of a mobile survey depends on weather 
conditions, the survey procedure, and whether the equipment has 
acceptable access to the location of the pipeline and possible gas 
migration paths. Some vendors have taken this concept a step further 
and combined highly sensitive gas detectors, some capable of detecting 
gas in the single ppb range, anemometers, GPS sensors, other sensors, 
and advanced analytics to enhance the capabilities of vehicle-based 
leakage surveys. Some advanced vehicle-based leak detection systems 
typically function by combining gas readings and wind indications to 
estimate the size and point of origin of a plume of gas as the vehicle 
drives through it. These leak indications (and gaps in the survey 
coverage) are then assessed by personnel with handheld equipment. For 
example, two studies measured gas concentrations in Boston, MA, and 
Washington, DC using Picarro mobile methane analyzer technology. In the 
2004 survey of Washington, DC, the researchers surveyed 1500 miles of 
streets using a Picarro G2301 spectrometer device and the Picarro A0491 
Mobile Plume Mapping Kit (A combination of the gas analyzer, a GPS 
device, and an anemometer). According to the equipment manufacturer, 
the G2301 device has sub 0.5 ppb precision over 5 seconds and an 
operating range of 0-20ppm when measuring methane,\160\ though testing 
of the device during the Boston study found analyzer output to be 
within 2.7 ppb of known gas concentration during testing.\161\ In 
Washington, DC, out of 5,893 methane readings detected from the vehicle 
with a concentration greater than 2.5 ppm, the minimum concentration 
defined as a leak indication in the study, 1,112 were measured at 5 ppm 
or greater.\162\ Additionally, the researchers inspected 19 of the 
larger emissions sources with a handheld combustible gas indicator and 
found gas concentration in nearby manholes exceeding 80% LEL (i.e., a 
grade 1 hazardous leak) at 12 locations. Upon notifying the 
distribution operator, a subsequent reinspection found that hazardous 
conditions remained at nine leak locations. In Boston, 435 out of 3,356 
methane indications were measured at 5 ppm or greater.\163\ However, 
these measurements are based on ``in-plume'' measurements consistent 
with the operation of the Picarro mobile methane analyzer and similar 
vehicle-based systems rather than direct measurements within 5 inches 
of the leak location. The concentration of each potential leak 
indication measured in-plume is likely to be lower than the 
concentration measured in the immediate vicinity of the emissions 
source during a leak investigation.
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    \160\ Picarro. G2301 Gas Concentration Analyzer Datasheet, 
https://www.picarro.com/g2301_gas_concentration_analyzer (last 
accessed Dec. 20, 2022).
    \161\ Phillips et al., ``Mapping Urban Pipeline Leaks: Methane 
Leaks Across Boston,'' 173 Environmental Pollution at 1-4 (2013).
    \162\ Jackson et al., ``Natural Gas Pipeline Leaks Across 
Washington, DC,'' 48 Environmental Science & Technology at 2051-2058 
(2014).
    \163\ Phillips et al., ``Mapping Urban Pipeline Leaks: Methane 
Leaks Across Boston,'' 173 Environmental Pollution at 1-4 (2013).
---------------------------------------------------------------------------

    Advanced vehicle-based leak detection systems were discussed 
extensively during the 2021 Public Meeting. A number of technology 
providers market automobile-based leak detection systems. EDF discussed 
their experience with advanced vehicle-based leak detection systems in 
partnership with Google and Pacific Gas and Electric (PG&E). According 
to EDF, research indicates that advanced mobile leak detection systems, 
vehicle-based platforms that rely on sensitive gas detectors, 
anemometers, GPS devices, other sensors, and analytics to locate the 
approximate source of gas plumes indicating possible leaks, can find 
more leaks in distribution systems compared to traditional survey 
methods. Also, according to EDF, one study found that surveys conducted 
by ``traditional'' methods in two cities failed to find 65 percent of 
the leaks that were discovered by advanced leak detection technologies, 
including some grade 1 leaks. EDF further commented that quantifying 
emissions can allow operators to prioritize replacement programs more 
effectively to the largest individual leaks.
    On the other hand, AGA noted issues with excessive ``false 
positives'' from mobile survey technologies, where there are 
indications of leaks where none exist. AGA also noted that mobile 
survey technologies can fail to detect

[[Page 31915]]

indications of a leak when a leak does exist. False positives require 
confirmation by operator personnel, and therefore cut into the cost-
effectiveness of such surveys. PHMSA, during the 2021 Public Meeting, 
noted that there are challenges with certain leak detection 
technologies depending on the area where the survey is being 
performed.\164\ For instance, driving surveys might best be conducted 
in densely populated areas where pipelines follow roadways. However, in 
rural areas with gas transmission and gathering pipelines, it can be 
more effective to use aerial surveys or continuous monitoring 
technology because pipeline rights-of-ways may be difficult to traverse 
on the ground. There might also be issues for operators using laser-
based and other line-of-sight equipment in some areas.
---------------------------------------------------------------------------

    \164\ Similarly, GPA and API submitted joint comments (Doc. No. 
PHMSA-2021-0039-0004) following the 2021 Public Meeting stating that 
the differences between gas gathering pipelines and gas transmission 
and distribution pipelines should be considered in developing any 
new regulations, guidance documents, or enforcement policies related 
to leak detection and repair.
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Aerial Sensors and Continuous Monitoring
    Other areas of industry interest are aerial sensing platforms and 
continuous monitoring. Aerial sensing involves gas detection equipment 
mounted on fixed wing or rotary wing aircraft, unmanned aerial systems 
(UAS), or satellites. Many aerial sensing methods are similar in 
principle to those used in advanced vehicle-based leak detection 
systems, except that the sensor suite is mounted on an aircraft or UAS, 
instead of a car or truck. Other aerial platforms may use direct 
sampling, laser-based methane detectors, LIDAR, OGI, or other methods 
that detect methane gas concentrations along a pipeline right-of-way or 
at aboveground facilities.
    Recent research and perspectives shared at the August 2021 EPA 
technology workshop described above illustrate the potential advantages 
of aerial survey technologies for certain oil and gas facilities. The 
primary advantage of aerial surveys is that the speed of an aircraft 
can allow more efficient or more frequent surveys of large areas. 
Depending on the configuration of the facility, aerial surveys are 
potentially highly cost-effective. For example, during a panel 
conversation on the first day of the 2021 EPA Methane Detection 
Technology Workshop, Triple Crown Resources reported cost-effective 
methane emissions reductions of up to 90% from upstream production 
facilities via aerial surveys performed by Kairos Aerospace.\165\ In 
addition to leak detection and repair procedures, the operator also 
made changes to its operations and maintenance procedures to address 
the minimization of releases from tanks and other equipment. In that 
same panel, another operator reported that aerial surveys were not 
cost-effective for all of their facilities, but that aerial surveys, 
especially those mounted on UAS, have the additional advantage of being 
able to maneuver around locations or facilities that may be difficult 
for operator personnel to safely access with traditional 
equipment.\166\ On the second day of the 2021 EPA Methane Detection 
Technology Workshop, a representative of BPX Energy (British 
Petroleum's onshore U.S. production business) described the company's 
quarterly aerial survey program using fixed wing aircraft and UAS in 
the Permian Basin, which is designed to detect, image, quantify, and 
map methane sources with an emissions rate greater than 5.5 mcf/d.\167\ 
BPX reported that the aerial surveys can cover over 100 square miles 
per day, although these surveys are susceptible to meteorological 
conditions. The advantages of aerial surveys are likely to be most 
significant on long-distance transmission lines that can be surveyed 
efficiently with fixed wing aircraft. Likewise, long-distance or dense 
gas gathering pipeline networks may also be cost-effective to survey by 
air.
---------------------------------------------------------------------------

    \165\ Johnson, Forrest and Wlazlo, Andrew. ``Airborne Methane 
Surveys Pay for Themselves: An Economic Case Study of Increased 
Revenue from Emissions Control'' Triple Crown Resources. EPA Methane 
Detection Technology Workshop (August 23, 2021). https://www.epa.gov/controlling-air-pollution-oil-and-natural-gas-industry/epa-methane-detection-technology-workshop. Day 1 at 2:32:15.
    \166\ Berrnica, P.E., ``Key Takeaways from Deploying Four Novel 
Methane Detection Technologies''.
    \167\ Faye Gerard, Ph.D. ``BPX, Methane Measurements.'' BP 
America. EPA Methane Detection Technology Workshop (August 24, 
2021). https://www.epa.gov/controlling-air-pollution-oil-and-natural-gas-industry/epa-methane-detection-technology-workshop. Day 
2 at 2:39:10.
---------------------------------------------------------------------------

    In contrast, drawbacks and limitations of aerial and continuous 
monitoring are similar to those of motor vehicle-based systems. While 
aircraft can access facilities that may be difficult to access with 
ground-based vehicles, the speed and altitude required for operation of 
fixed wing aircraft and helicopters can reduce the reliability of 
detecting smaller releases since gas concentration decreases with 
distance from the source and increased speed decreases the likelihood 
that an accurate measurement will be taken as the vehicle intersects a 
gas plume. Additionally, aerial surveys may not be cost-effective for 
some system configurations. Most research and application of aerial 
systems have been in the upstream sector on gas production, processing, 
and gathering systems.
    PHMSA expects that use of UAS for aerial monitoring will grow as 
technology continues to advance, and the Federal Aviation 
Administration (FAA) continues its work to integrate UAS into the 
National Airspace System. On January 15, 2021, FAA published a final 
rule to permit the operation of UAS at night and over people under 
certain conditions.\168\ FAA is currently considering recommendations 
from an Aviation Rulemaking Committee on a regulatory approach to 
support beyond visual line of sight operations in the National Airspace 
System.\169\
---------------------------------------------------------------------------

    \168\ FAA, ``Operation of Small Unmanned Aircraft Systems Over 
People,'' 86 FR 4314 (Jan. 15, 2021).
    \169\ Unmanned Aircraft Systems Beyond Visual Line Of Sight 
Aviation Rulemaking Committee Final Report, March 2022, available at 
https://www.faa.gov/regulations_policies/rulemaking/committees/documents/media/UAS_BVLOS_ARC_FINAL_REPORT_03102022.pdf.
---------------------------------------------------------------------------

    Continuous monitoring can take many forms and is a fast-maturing 
area of development. The most straightforward means of providing 
continuous monitoring is with stationary gas detectors that are able to 
communicate with operator personnel or a control center. The most 
straightforward means of continuous monitoring is mounting stationary 
sensors such as gas samplers or laser-based detectors in the vicinity 
of a pipeline. A stationary gas sampler must be located near potential 
leak locations in order to detect leaks, laser-based systems must have 
potential leak sources or migration paths within the line of sight and 
effective range of the device, though some newer devices are capable of 
scanning. Continuous monitoring with such sensors can therefore be 
costly, since more devices are required versus using one device to 
perform a survey, however real time leak information is a significant 
advantage, especially for intermittent sources. For example, the BPX 
Energy presentation at the 2021 EPA Methane Detection Technology 
Workshop noted that the company's stationary sensors refresh every 15 
minutes.\170\ For this reason, continuous monitoring can be especially 
effective at aboveground facilities where probable fugitive emissions 
sources are known

[[Page 31916]]

beforehand and at high-risk locations where real-time alarms can help 
ensure public safety from fire and explosion risk.
---------------------------------------------------------------------------

    \170\ Faye Gerard, Ph.D. ``BPX, Methane Measurements.'' BP 
America. EPA Methane Detection Technology Workshop (August 24, 
2021). https://www.epa.gov/controlling-air-pollution-oil-and-natural-gas-industry/epa-methane-detection-technology-workshop. Day 
2 at 2:48248.
---------------------------------------------------------------------------

    Vendors and operators have been experimenting with a number of 
methods such as pressure wave monitoring, acoustic monitoring, in-ditch 
sensing with fiber optic sensors, and other devices. At the May 2021 
Public Meeting, Siemens Energy and ProFlex Technologies presented on a 
negative pressure wave sensing technology for detecting ``spontaneous 
leaks'' on gas transmission, gas gathering, and similar applications. 
In that technology, pressure sensors placed periodically along the 
pipeline can detect anomalous negative pressure waves that propagate 
from the location of a rupture. According to the technology provider, 
the system can detect, by timing the rupture indications on the 
upstream and downstream sensors, estimate the location of the rupture 
within 20-50 linear feet. The technology provider claims that the 
system can detect leaks between \1/2\ inch to 2 inches in area within a 
few seconds, therefore is potentially a sensitive and reliable means of 
detecting pipeline ruptures, however the system may not be able to 
reliably detect smaller leaks.\171\
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    \171\ ProFlex Technologies and Siemens. ``Siemens Energy 
Spontaneous Leak Detection Service powered by ProFlex.'' May 2021. 
https://primis.phmsa.dot.gov/meetings/FilGet.mtg?fil=1154.
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In-Residence Methane Detection Tools
    Another emerging area of industry interest is in-home methane 
detection. While gas piping downstream from the outlet of a customer 
meter is not regulated under the Federal pipeline safety regulations, 
PHMSA encourages the adoption of in-home methane detectors by 
operators, States, and standards developing organizations. As a result 
of NTSB investigations into a series of gas-related incidents in a 
neighborhood in Dallas, Texas in late February of 2018,\172\ and an 
investigation into an apartment explosion in Silver Spring, MD,\173\ 
the NTSB included in-home methane detection on its 2021-2022 NTSB Most 
Wanted List.\174\ NTSB recommended that the International Code Council, 
the National Fire Protection Association, and the Gas Technology 
Institute (GTI) cooperate to develop standards and incorporate 
provisions in applicable national codes to require methane detection 
systems for all types of residential occupancies with gas service. The 
NTSB recommended that, at a minimum, these requirements should cover 
the installation, maintenance, placement of the detectors, and testing 
requirements. The PST and other public safety advocacy groups have also 
called on operators to install this technology wherever possible to 
provide for better public and environmental safety, as this technology 
can provide an extra level of protection against dangerous leaks. At 
the 2021 Public Meeting, the PST stated that the increased usage of in-
home methane detectors would be relatively inexpensive and have the 
potential to dramatically reduce injuries, property damage, and deaths 
resulting from leaks and explosions from gas distribution systems.
---------------------------------------------------------------------------

    \172\ NTSB, Pipeline Accident Report 21-01, ``Atmos Energy 
Corporation Natural Gas-Fueled Explosion; Dallas, Texas; February 
23, 2018'' (Jan. 12, 2021).
    \173\ NTSB, Pipeline Accident Report 19-01, ``Building Explosion 
and Fire: Silver, Spring, Maryland: August 10, 2016'' (Apr 24, 
2019).
    \174\ NTSB, ``Improve Pipeline Leak Detection and Mitigation: 
2021-2022 Most Wanted List of Transportation Improvements'' (Apr. 6, 
2021).
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Integration of Advanced Technologies and Practices Within Advanced Leak 
Detection Programs
    Each of the commercially available, advanced technologies described 
above have inherent limitations that make their use more or less 
appropriate for use in connection with different gases, pipeline 
facilities, operating environments, weather conditions, and other 
factors. And even state-of-the-art equipment can deliver poor results 
if the operator's procedures or training are inadequate or if equipment 
malfunctions. For this reason, a number of speakers during the 2021 
Public Meeting emphasized that ALDPs must consist of a portfolio of 
mutually reinforcing advanced leak detection technologies, practices, 
and policies, each providing defense-in-depth for the inherent or 
operational limitations of other program elements.
    An incident that occurred on a gas distribution pipeline operated 
by Atmos Energy, in Dallas, Texas on February 23, 2018, that had been 
surveyed shortly before the incident illustrates this truism.\175\ 
Prior the February 23 incident, two other gas-related fires occurred on 
the same block on February 21 and February 22. The NTSB concluded that 
it is likely that the three incidents are related, but fire department 
investigators and operator personnel failed to pinpoint the source of 
the leak that led to the February 23 incident. Since the fire 
department and the operator had not identified the distribution 
pipeline as the cause of the first two fires, no incident was reported 
to PHMSA. Following the February 22 fire, Atmos performed a leakage 
survey and repaired high-priority leaks on the pipeline segment 
involved in the incident. Atmos Energy's leakage surveys incorporated 
modern leak detection equipment such as FIDs, optical methane 
detectors, remote methane leak detectors (RMLD, a type of laser-based 
gas detector), and other devices. However, the manufacturer's 
instructions for the RMLD devices used to perform the leakage survey 
noted that the device performs sub-optimally in wet conditions and is 
not to be used when sustained wind or gusts exceed 15 mph. 
Additionally, the operator's combustible gas indicator could be damaged 
when saturated. Due to precipitation, wind, and wet soil conditions, 
the operator's RMLD survey was ineffective and the operator's barhole 
\176\ procedures to measure gas concentrations in the soil could not be 
performed. As a result, the operator failed to detect leaking gas from 
a cracked main, resulting in a third, fatal explosion on February 23, 
2018.
---------------------------------------------------------------------------

    \175\ NTSB, Pipeline Accident Report 21/01 ``Pipeline Accident 
Report: Atmos Energy Corporation Natural Gas-Fueled Explosion: 
Dallas, Texas: February 23, 2018'' (Jan. 12, 2021).
    \176\ A barhole is a small hole dug into the ground in order to 
measure the concentration of gas within the soil by taking a sample 
within the barhole with a probe.
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5. State-Level and Operator Leak Detection and Repair Requirements
    PHMSA regulations, as explained in section II.D.1 above, require 
operators of part 192-regulated gas transmission and distribution 
pipelines and certain regulated gathering pipelines to repair hazardous 
leaks promptly--without providing meaningful guidance regarding which 
leaks are hazardous, or precisely when any leaks must be repaired. The 
limitations of regulatory initiatives undertaken by State authorities 
and voluntary efforts (including methane emissions reduction 
commitments and pertinent industry standards) by pipeline operators, 
moreover, underscore the need for robust Federal leak detection, 
grading, and repair requirements.
GPTC Guide
    The GPTC is an ANSI-accredited committee (ANSI Z380, or the 
Committee) that was formed in the late 1960s under the American Society 
of Mechanical Engineers. The Committee operates under a consensus 
process and is technically based and independent. The Committee is 
composed of

[[Page 31917]]

approximately 100 members from all facets of the gas industry, 
including gas distribution, transmission, storage, and gathering 
operators and manufacturers of gas-related equipment. The Committee 
also has members from the regulatory community, including PHMSA, the 
National Transportation Safety Board (NTSB), and other Federal and 
State regulatory agencies. Approximately 40 of the Committee's members, 
including PHMSA, are voting members.
    The Committee publishes the GPTC Guide as an implementation tool 
facilitating compliance by gas pipeline operators with PHMSA regulatory 
requirements.\177\ The first edition of the GPTC Guide was published in 
1970, around the same time the Federal Pipeline Safety Regulations were 
first promulgated. The GPTC Guide is under continuous review and may be 
updated when prompted by pending rulemakings, NTSB reports, and 
requests from stakeholders, including PHMSA, the National Association 
of Pipeline Safety Representatives (NAPSR), or members of the public. 
The Committee periodically reviews requests for updates and may create 
a task group, if necessary, to issue new or amended guidance of 
versions of the GPTC Guide. The current edition of the GPTC Guide is 
the 2022 edition (including Addendum 1), published in June 2022.
---------------------------------------------------------------------------

    \177\ GPTC Guide at 18 (``While the GPTC Guide is intended 
principally to guide operators of natural gas pipelines, it is a 
valuable reference for operators of other pipelines covered by Part 
192'').
---------------------------------------------------------------------------

    Like the Federal Pipeline Safety Regulations, the GPTC Guide's leak 
grading and repair criteria are focused primarily on public safety 
rather than environmental protection. While the GPTC Guide itself has 
not been incorporated by reference in the Federal Pipeline Safety 
Regulations, several States have adopted at least the tiered leak 
grading criteria of the GPTC Guide and associated repair requirements 
into their regulations governing gas pipelines,\178\ and PHMSA has 
referenced it from time-to-time in its implementing guidance.\179\ 
Additionally, some gas pipeline operators incorporate sections of the 
GPTC Guide into their operating and maintenance procedural manuals for 
detecting, investigating, and classifying leaks.
---------------------------------------------------------------------------

    \178\ See National Association of Pipeline Safety 
Representatives (NAPSR), Compendium of State Pipeline Safety 
Requirements and Initiatives Providing Increased Public Safety 
Levels Compared to Code of Federal Regulations, Third Edition (Feb. 
2022) (Compendium). References to ``NAPSR'' or to pertinent State 
requirements in this NPRM will, unless otherwise noted, will be to 
information within the Compendium.
    \179\ See, e.g., PHMSA, ``Distribution Integrity Management: 
Guidance for Master Meter and Small Liquefied Petroleum Gas Pipeline 
Operators'' (2013) at 2 (directing larger distribution pipeline 
operators to refer to GPTC guidelines); PHMSA, Interpretation 
Response Letter No. PI-93-009 (February 11, 1993) (recommending 
public stakeholder consult the GPTC Guide for further determination 
of instruments and techniques to be used in certain leak detection 
activities); see also PHMSA, Interpretation Response Letter No. PI-
99-0105 (December 1, 1999) (stating that the GPTC Guide ``is a 
document endorsed by us which contains information and some methods 
to assist the gas pipeline operator in complying with the 
regulations contained in 49 CFR part 192'').
---------------------------------------------------------------------------

    The GPTC Guide contains appendices that provide procedures that 
comply with part 192. The GPTC Guide also provides guidance for 
controlling methane leaks from natural gas pipeline leaks in Appendix 
G-192-11 For gas distribution pipelines, section 6.2 of the DIMP 
guidance in Appendix G-192-8 describes possible elements of an 
``effective leak management program'' and references the criteria for 
grading leaks from Appendix G-192-11 and, for liquefied petroleum gas 
(LPG) systems, Appendix G-192-11A. Each section includes tables 3a, 3b, 
and 3c summarizing the grading criteria and recommended repair 
requirements. The grading criteria from GPTC Guide Appendix G-192-11 
and Appendix G-192-11A are discussed below (hereafter, references to 
the GPTC Guide refer specifically to Appendix G-192-11 and 11A unless 
otherwise specified).
    Section 5.5 of the GPTC Guide characterizes a grade 1 leak as a 
``leak that represents an existing or probable hazard to persons or 
property, and requires immediate repair or continuous action until the 
conditions are no longer hazardous.'' This mirrors the definition of a 
``hazardous leak'' at Sec.  192.1001. This characterization omits 
consideration of potential hazard to the environment, and the phrase 
``existing or probable hazard'' is not defined in any part of the GPTC 
Guide. However, Table 3a of the GPTC Guide provides the following 
examples of grade 1 leaks:
    (1) Any leak that, in the judgment of operating personnel at the 
scene, constitute an immediate hazard.
    (2) Escaping gas that is ignited.
    (3) Any indication of gas which has migrated into or under a 
building, or into a tunnel.
    (4) Any indication of gas which has migrated to at an outside wall 
of a building where gas would likely migrate or into a tunnel.
    (5) Any reading of 80% [of the lower explosive limit] LEL, or 
greater, in a confined space.\180\
---------------------------------------------------------------------------

    \180\ The Lower Explosive Limit (LEL) is the lowest 
concentration of gas that will burn in air in the presence of an 
ignition source.
---------------------------------------------------------------------------

    (6) Any reading of 80% LEL, or greater, in small substructures 
(other than gas-associated substructures) from which gas would likely 
migrate to the outside wall of a building.
    (7) Any leak that can be seen, heard, or felt, and which is in a 
location that may endanger the general public or property.
    Building on the Sec.  192.703(c) requirement that hazardous leaks 
(i.e., grade 1 leaks) be repaired promptly, the GPTC Guide further 
specifies that an operator must take immediate and continuous action to 
protect life and property until the conditions are no longer hazardous. 
Per the GPTC Guide, such continuous actions could include: implementing 
an emergency plan written in accordance with Sec.  192.615; evacuating 
the premises; blocking off an area; re-routing traffic; eliminating 
ignition sources; and venting the area by removing manhole covers, bar-
holing, or installing vent holes. The GPTC Guide also notes that, for 
grade 1 leaks, operators should stop the flow of gas by closing valves 
or by other means and notify appropriate police and fire departments.
    A grade 2 leak is an intermediate risk classification in the GPTC 
Guide. The GPTC Guide characterizes a grade 2 leak as a ``leak that is 
non-hazardous at the time of detection but that requires or justifies a 
scheduled repair based on probable future hazard.'' Like the 
description of a grade 1 leak, the characterization of a grade 2 leak 
in the GPTC Guide does not address hazards to the environment and does 
not provide a definition for the term ``probable future hazard,'' 
although example criteria are provided in Table 3b of the GPTC Guide. 
For grade 2 leaks, these criteria include leaks that require action 
ahead of the ground freezing, or where changes in venting conditions 
would likely cause gas to migrate to the outside wall of a building. 
Grade 2 leaks could also include leaks with a reading of 40% of the LEL 
or greater under a sidewalk in a wall-to-wall paved area that does not 
qualify as a grade 1 leak; a reading of 100% LEL or greater anywhere 
under a street in a wall-to-wall paved area that has significant gas 
migration and does not qualify as a grade 1 leak; a reading between 20% 
and 80% of the LEL in a confined space or in a small substructure; any 
non-zero concentration reading on a pipeline

[[Page 31918]]

operating at 30% of SMYS or greater in a Class 3 or Class 4 location 
that does not qualify as a grade 1 leak; and finally, any leak that, in 
the judgment of the operating personnel at the scene, is of sufficient 
magnitude to justify or require a scheduled repair. These examples 
demonstrate that the grade 2 leak classification, like the grade 1 
classification, focuses operators on hazards to persons and property, 
without consideration of impacts on our environment.
    The GPTC Guide requires that, upon detecting a grade 2 leak, an 
operator should repair or clear the leak ``within one calendar year but 
no later than 15 months from the date the leak was reported.'' The GPTC 
Guide states that, in determining the repair priority for the leak, an 
operator should consider the extent of gas migration, the proximity of 
gas to buildings in sub-surface structures, and the soil conditions 
(including frost cap, moisture, or natural venting). Operators can take 
a range of actions in addressing grade 2 leaks under the GPTC Guide. 
Some grade 2 leaks that are evaluated by the criteria listed above may 
justify a scheduled repair within 5 working days, whereas others might 
justify repair within 30 days. The GPTC Guide suggests that operators 
should schedule some grade 2 leaks for repair on a ``normal routine 
basis,'' with periodic re-inspection as necessary. The GPTC Guide 
suggests that operators should reevaluate grade 2 leaks at least once 
every 6 months until they are cleared, establishing a frequency of 
reevaluation based on the location and magnitude of the leak.
    The GPTC Guide characterizes a grade 3 leak as ``a leak that is 
non-hazardous at the time of detection and can reasonably be expected 
to remain non-hazardous.'' The term ``non-hazardous'' is not itself 
defined, but comparison to the grade 1 and grade 2 descriptions 
indicates that the grade 3 classification is intended to be a catch-all 
classification for all leaks that do not constitute either grade 1 or 
grade 2 leaks, including those leaks that are hazardous to the 
environment without representing a potential risk to public safety. 
Based on the criteria in Table 3c, grade 3 leaks would include leaks 
where there is a reading of less than 80% LEL in a small gas-associated 
substructure, any reading under a street in areas without wall-to-wall 
paving where it is unlikely that gas could migrate to the outside wall 
of a building, and any reading of less than 20% LEL in a confined 
space. The GPTC Guide suggests that operators should reevaluate grade 3 
leaks during their next scheduled survey, or within 15 months of the 
date the leak is reported, whichever comes first, and continue 
reevaluations until the leak is either regraded or is no longer 
leaking. The GPTC Guide does not require the repair of grade 3 leaks. 
In comments submitted following the 2021 Public Meeting, AGA et al. 
noted the limitations of the GPTC Guide leak grading system with 
respect to environmental safety in light of the GPTC Guide's focus on 
repair and remediation of leaks that are hazardous to public safety 
only.
    The GPTC Guide provides for re-grading of existing leaks based on 
changes identified during subsequent evaluations. If an operator 
discovers, during a reevaluation, that a grade 2 or 3 leak has become 
worse following its initial detection and grading to the point where it 
would now be classified at a higher grade, an operator must upgrade the 
leak to its appropriate grade and take appropriate action in accordance 
with the new grade. The GPTC Guide also permits operators to downgrade 
leaks by making temporary repairs to make the leak less hazardous. For 
example, an operator may vent a grade 1 leak by drilling multiple 
barholes into the soil in the immediate vicinity of the leak or by 
leaving vault boxes open to the atmosphere before grading the leak. 
These techniques can ensure that a leak is not an immediate hazard to 
persons or property and justify downgrading the leak to a grade 2 leak.
    As described in section II.D.1, existing regulations require repair 
of hazardous leaks. In practice, the term hazardous leak has 
corresponded to a grade 1 leak under the three-grade leak 
classification framework in the GPTC Guide; a grade 1 leak is the most 
urgent classification under this framework. Section 5.5 of appendix G-
192-11 of the GPTC Guide characterizes a grade 1 leak as one that 
``represents an existing or probable hazard to persons or property and 
requires immediate repair or continuous action until the conditions are 
no longer hazardous.'' However, PHMSA regulations do not currently 
require the repair of leaks other than hazardous leaks that would be 
classified as grade 2 or grade 3 based on the GPTC Guide. Regarding the 
replacement or remediation of pipelines known to leak, appendix G-192-
18 of the GPTC Guide suggests operators consider replacement of cast 
iron pipe based on the maintenance and leak history and operational and 
environmental circumstances and provides guidance on factors and 
situations to consider.
State Leak Detection, Repair, and Reporting Requirements
    State regulatory requirements impose a patchwork of obligations on 
pipeline operators with respect to leak detection and repair. Pertinent 
requirements vary from one State to the next and even within a single 
State based on the type (gathering, transmission, or distribution) of 
pipeline in question or the gas being transported. Many of those State 
requirements are (like PHMSA's current regulations) directed toward 
addressing imminent public safety risks rather than the climate and 
potential future safety risks posed by gas pipeline leaks. And, 
according to NAPSR data, only a minority of the States have leak 
detection and repair regulations that exceed the current minimum 
Federal regulations for any type of gas pipeline.\181\
---------------------------------------------------------------------------

    \181\ Zanter, Mary. ``Presentation of NAPSR at 2021 Public 
Meeting'' (May 5, 2021), https://primis.phmsa.dot.gov/meetings/FilGet.mtg?fil=1150.
---------------------------------------------------------------------------

    A handful of States require more frequent leakage surveys than 
required by part 192. Many of those survey requirements apply to only 
certain types of pipelines, with more demanding requirements for 
distribution systems than for other types of gas pipelines (e.g., 
gathering, intrastate transmission lines). And those requirements 
typically are directed toward addressing public safety rather than 
environmental harms, targeting areas where gas is likely to accumulate, 
where there is a high safety hazard in the case of a gas explosion, or 
pipelines that are higher risk due to their pressure or material. For 
example, the California Public Utility Commission requires annual 
leakage surveys ``in the vicinity of schools, hospitals and churches,'' 
in addition to the requirements for business districts in Sec.  
192.723, and requires that gas transmission pipelines be surveyed using 
leak detection equipment at least twice each year. Maryland requires 
annual leakage surveys for service pipelines serving places of public 
assembly. South Carolina requires leakage surveys for cathodically 
unprotected distribution pipelines at least once every 12 months, 
rather than 3 years as specified in Sec.  192.723. Certain States also 
require operators to conduct more frequent surveys based on the 
location of the pipeline; for example, if the pipeline delivers gas to 
high-occupancy buildings or buildings of public assembly such as 
theaters, hospitals, or schools, or if the pipeline is near bridges or 
other transportation infrastructure. Other States provide a definition 
of the term ``business

[[Page 31919]]

district'' subject to more frequent leakage surveys in Sec.  192.723 
but not defined in part 192. While a small minority of States do have 
increased surveying of cast iron pipes under certain conditions, few 
States require operators to replace or remediate these or other types 
of leak-prone pipe materials.
    A minority of States have more specific requirements for the use of 
leak detection equipment than contemplated by current PHMSA 
regulations. NAPSR's Compendium identified three States with leak 
detection equipment requirements that are more demanding than PHMSA's 
requirements. Those States' requirements seem largely focused on 
methane leaks from natural gas pipelines rather than leaks from 
pipeline facilities transporting other gases. A handful of states 
specify allowable leak detection equipment, generally requiring the use 
of an FID or equivalent device. For example, Maryland regulations 
require the use of flame ionization, combustible gas indicator in a 
barhole, optical methane detector, or other method approved by the 
Maryland Public Service Commission. New Jersey adopted an energy-
related master plan in their overall State-wide climate goals that 
specifically directs the State utility commission to establish a 
standard for the use of advanced leak detection technologies when 
performing leakage surveys. NAPSR data indicates, however, that a 
majority of States do not have any more demanding requirements than 
PHMSA for the leak detection equipment used by operators. NAPSR's 
Compendium similarly indicates that few States have right-of-way patrol 
requirements for gas gathering or transmission pipelines more demanding 
than those in current PHMSA regulations.
    Most States, moreover, do not have reporting requirements for leaks 
that are more demanding than those in current PHMSA regulations. 
NAPSR's Compendium indicates only a handful of States require periodic 
submission of leak status reports for any type of pipeline to State 
regulators, with a few States having recently adopted more 
comprehensive leak reporting requirements to achieve methane emission 
reduction goals. For example, California has established a 
comprehensive reporting system for gas utilities to submit annual 
methane leak abatement reports and compile emission reduction plans.
    Apart from leak detection requirements, NAPSR's Compendium yields 
that a majority of States have neither adopted the GPTC Guide's leak 
grading and repair criteria, nor have regulatory requirements 
supplementing the requirements for leak grading or leak repair in part 
192. A few States (such as Texas, Kentucky, Massachusetts, and New 
York) have adopted leak grading and repair standards similar to those 
in the GPTC Guide. But many more States reported to NAPSR that they 
automatically adopt PHMSA's pipeline safety regulations for leak 
grading and repair into their regulations and do not otherwise 
introduce more stringent requirements. Some of those States noted that 
they assume some operators follow the guidance in the GPTC Guide on the 
grading and repair of leaks described in section II.D.8. Few States 
have specific requirements for replacement of gas pipelines known to 
leak based on material, design, or past operating and maintenance 
history; among those States, replacement initiatives generally focused 
on gas distribution pipelines rather than gas gathering or transmission 
pipelines.
    Of that minority of States that have regulations exceeding the 
current requirements in part 192 for grading and repairing leaks, most 
indicated that they followed a grading system resembling the GPTC 
grading system, where they classify leaks as grade 1, grade 2, or grade 
3 based on relative safety hazards. However, these States may not 
impose leak grading and repair requirements uniformly across each type 
(gathering, transmission, and distribution) of pipeline. Mandatory 
repair timelines also differed among those States--particularly with 
respect to grades 2 and 3 leaks.
    With respect to grade 2 leaks, some States do not have specific 
requirements for monitoring and repair and defer to operator 
procedures. Other States noted they require operators to recheck these 
leaks on subsequent surveys, per an operator's procedures. Some States 
have requirements for operators to reassess grade 2 leaks every 6 
months, with a few States requiring additional (or monthly) surveys 
until the leaks are cleared. There is also a wide variety of State 
approaches to repair timelines for grade 2 leaks: the States largely 
require the repair of grade 2 leaks anywhere from 12 months to 24 
months after the date of discovery, with a handful of States requiring 
more immediate repairs.
    With respect to grade 3 leaks, monitoring requirements for grade 3 
leaks also vary widely between those States with grade 3 leak grading 
and repair requirements, with some States requiring operators to 
monitor grade 3 leaks every 6 months, and other States requiring 
operators to monitor grade 3 leaks every 15 months. The States that 
have requirements for repairing grade 3 leaks follow one of two paths: 
either the State requires that grade 3 leaks be repaired within a 
prescriptive timeframe, such as 24, 30, or 36 months after discovery, 
or the State requires operators to have only a defined maximum number 
of outstanding grade 3 leaks. Some States only require operators to 
repair grade 3 leaks if the leaks have a relatively high emission rate. 
The methods for identifying high-emitting grade 3 leaks vary by State. 
For example, Massachusetts defines an ``environmentally significant'' 
grade 3 leak as one with a ``leak extent'' (land area affected by gas 
migration) of 2,000 square feet or greater, or with a highest barhole 
reading of 50% or more gas in air and requires its repair within either 
2 years or 12 months, depending on the extent of migration. Some States 
noted that they required operators to perform additional leakage 
surveys after repairs are completed.
Industry Methane Leak Detection and Repair Practices and Efforts
    Pipeline operator leak detection and repair practices are similarly 
insufficient to meet the risks to the environment and public safety 
from leaks of methane and other gases from gas pipeline infrastructure. 
Operators employ a spectrum of approaches and technology in connection 
with leak detection and repair--most of which are focused on compliance 
with pertinent Federal and State regulations that themselves 
inadequately address the public safety and environmental risks arising 
from all leaks on gas transmission, distribution, and part 192-
regulated gathering pipelines. Although recent voluntary industry 
approaches pertaining to leak detection and repair are welcome, those 
efforts generally exhibit shortcomings (including meager participation, 
limited application to different pipeline facilities, absence of 
meaningful leak reduction targets, or a lack of transparency, limited 
application to natural gas pipelines), underscoring the need for timely 
Federal regulatory intervention. Moreover, while progress has been made 
on efforts to replace or remediate any pipeline known to leak based on 
material (such as cast iron, unprotected steel, wrought iron, and 
historic plastics with known issues), design, or past operating and 
maintenance history, it remains an issue. For example, according to 
PHMSA annual reports, 18,314 miles of cast or wrought iron distribution 
mains and 6,518 service lines remained in operation at the end of 2021.
    Individual operators' leak detection and repair programs have 
historically

[[Page 31920]]

focused on ensuring compliance with pertinent Federal and State 
requirements that (as explained above) generally lack meaningful 
requirements for timely grading and repair of leaks other than 
``hazardous leaks.'' For those leaks from gas transmission, regulated 
gathering, and distribution facilities that are not considered 
``hazardous'' under current PHMSA regulations, some operators may 
incorporate the GPTC Guide leak identification, grading, and mitigation 
criteria within their inspection and maintenance procedures, using the 
``LEAKS'' mnemonic as an aide to their personnel tasked with managing 
leak detection and remediation.\182\ However, not all operators 
incorporate the GPTC Guide within their inspection and maintenance 
procedures; similarly, operators who integrate the GPTC Guide in their 
procedures include revision/amendment to those procedures, or may not 
adopt those procedures across all types of gas pipelines on their 
system.
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    \182\ The ``LEAKS'' management system mnemonic consists of 
Locating the leak, Evaluating its severity, Acting appropriately to 
mitigate the leak, Keeping records, and Self-assessing to determine 
if additional actions are necessary to keep the pipeline system 
safe.
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    Individual operators employ a range of equipment and technologies, 
with some operators employing advanced technologies such as infrared 
technologies, FIDs, and laser gas detectors to satisfy pertinent 
leakage survey requirements. For example, during the 2021 Public 
Meeting, a representative from the Knoxville Utilities Board (KUB), a 
gas distribution pipeline operator and member of the American Public 
Gas Association (APGA), noted that it performs leakage surveys by using 
handheld laser leak detectors while walking pipelines or travelling 
rights-of-ways with a Segway. For its distribution mains, KUB stated 
that it assesses those pipelines using a mobile method employing a 
traditional laser detector mounted in a vehicle, driving at lower 
speeds, and surveying major roads at night. During leakage surveys, if 
KUB technicians find an indication of a leak, they pinpoint the leak's 
specific location. If the leak can be fixed with a minor repair--
through an adjustment, a tightening, or lubrication--the technicians 
will make the repair on-site. If the technicians find a grade 1 leak 
during a survey, KUB stated the technicians stay on-site and provide 
site safety until a repair crew can make the appropriate, immediate 
repairs. KUB stated that they repair any discovered grade 2 leaks 
within 90 days, and grade 3 leaks within 6 months, but they also noted 
in their presentation during the 2021 Public Meeting that repair 
schedules can vary from operator to operator. Similarly, Kinder Morgan 
during the 2021 Public Meeting stated that it employed a variety of 
methods and technologies (foot patrols; aerial surveys by fixed-wing 
aircraft or helicopter; automobile-borne sensors when the right-of-way 
is accessible) to perform right-of-way patrols on its transmission 
lines. However, these practices are not universal; rather (as explained 
above), the 2021 Public Meeting underscored that many operators are 
only beginning to integrate advanced leak detection technologies 
throughout their systems.
    So far, voluntary industry standards have not resulted in operators 
employing adequate leak detection and repair practices. The non-
mandatory Appendix M to ASME B31.8S, ``Gas Transmission and 
Distribution Piping Systems'' contains leak grading and repair criteria 
similar to the contents of the GPTC Guide.\183\ However, that 
standard--like the GPTC Guide--specifies neither technology nor 
performance requirements for operator leak detection programs, and it 
contains no repair schedule for grade 3 leaks. In addition, PHMSA also 
understands that not every gas pipeline operator incorporates ASME 
B31.8-2007 into their inspection and maintenance procedures.
---------------------------------------------------------------------------

    \183\ ASME, B31.8-2007, Gas Transmission and Distribution Piping 
Systems, 2007 Edition (2008) (ASME B31.8-2007). PHMSA regulations 
incorporate by reference elements of ASME B31.8-2007 in connection 
with yield strength testing procedure (Sec.  192.619(a)(1)(i)) or 
the alternative MAOP requirements (Sec.  192.620)--but not non-
mandatory appendix M.
---------------------------------------------------------------------------

    Following the May 2021 Public Meeting, AGA et al. highlighted a 
handful of the voluntary industry initiatives to reduce methane 
emissions--including leaks from gas gathering, transmission, and 
distribution pipelines.\184\ However, publicly available information 
regarding those efforts does not confirm that leaks on gas 
transmission, distribution, and regulated gathering are detected and 
repaired in a timely manner. Precisely which pipeline operators and 
which pipeline facilities are captured by each initiative is generally 
not clear, but participation is far from universal among operators and 
pipeline facilities that would be subject to the amendments to part 192 
contemplated in this NPRM. And even in those initiatives for which 
there is publicly available, operator-specific information, the focus 
is less on pipeline leak detection and repair than on other potential 
sources of methane emissions (e.g., blowdowns, excavation damages). For 
example, while the Methane Challenge Best Management Practice 
Commitment Option documentation describes compressor station equipment 
leaks, it does not address leak detection and repair on buried pipeline 
facilities other than recommended replacement of cast iron and bare 
steel distribution pipelines \185\ Indeed, a review of publicly 
available information on the initiatives identified by AGA et al. does 
not indicate discrete emissions reduction targets for different 
operators or types of pipeline facilities. Only a minority of the 
initiatives identified by industry trade groups publish any data on the 
methane emissions reductions achieved--and that data does not show 
which specific operators are achieving their performance targets. 
Publicly available information does not demonstrate that these 
voluntary initiatives have led to reductions in emissions of methane 
and other gases.
---------------------------------------------------------------------------

    \184\ AGA et al. at Appendix A.
    \185\ See EPA, ``Methane Challenge Program BMP Commitment Option 
Technical Document'' at 10 and 24-28 (May 2022), https://www.epa.gov/system/files/documents/2022-05/MC_BMP_TechnicalDocument_2022-05.pdf (last accessed December 18, 
2022).
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6. Damage Prevention
    Reducing excavation damage to pipelines has historically been a 
focus of PHMSA's efforts in controlling public safety risks from gas 
pipelines--but is also an important component of mitigating harmful GHG 
emissions. Excavation damage creates a safety hazard for the public, 
the excavator, and the affected pipeline facility operator, and can 
lead to significant emissions going unnoticed or ignored if not posing 
an imminent public safety hazard. According to PHMSA data presented by 
AGA representatives at the 2021 Public Meeting, excavation damage in 
2020 alone resulted in the loss of 245,000 MCF of gas from gas 
distribution pipelines--equivalent to the amount of emissions produced 
by 34 million miles driven by a vehicle or 50 million pounds of coal 
burned.\186\ PHMSA incident reports have identified incidents caused by 
excavation damage that was not discovered for some time, or where no 
excavation work was ever reported.
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    \186\ Sames, ``Presentation of AGA at 2021 Public Meeting'' at 
slide 7 (May 5, 2021), https://primis.phmsa.dot.gov/meetings/FilGet.mtg?fil=1139.
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    Nevertheless, some State excavation damage prevention programs may 
not adequately address these risks. PHMSA has taken steps in recent 
years to establish and improve comprehensive implementation of State 
programs

[[Page 31921]]

designed to prevent damage to underground pipeline facilities. First, 
PHMSA published a final rule in 2015 establishing procedures at 49 CFR 
part 198 for evaluating State excavation damage prevention law 
enforcement programs and enforcing minimum Federal damage prevention 
standards in States where damage prevention law enforcement is deemed 
inadequate or does not exist.\187\ PHMSA audited State damage 
prevention programs for adequacy under those new procedures in 2016, 
determining that 27 States had inadequate damage prevention enforcement 
programs. Second, PHMSA provides States with damage prevention grants 
to establish and improve comprehensive State damage prevention 
programs. Third, PHMSA's maintenance of the NPMS database gives 
pipeline operators, emergency response personnel and State and Federal 
regulatory authorities, as well as (to a lesser extent, given 
restrictions on data access) members of the public, data on location 
and other material characteristics of gas transmission pipelines, 
thereby reinforcing Federal and State damage prevention initiatives.
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    \187\ PHMSA, ``Pipeline Safety: Pipeline Damage Prevention 
Programs--Final Rule,'' 80 FR 43835 (July 23, 2015).
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    But even in States with robust damage prevention programs, limited 
information on buried gas pipelines can hamstring efforts to reduce 
excavation damage and marshal emergency response to any resulting 
incidents. This is particularly true for gas gathering pipelines. 
Despite recently expanded requirements that operators of certain gas 
gathering pipelines maintain sufficient damage prevention programs 
under Sec.  192.614, PHMSA regulations do not currently require 
operators of gas gathering pipelines to submit geospatial location data 
into NPMS. This regulatory gap means that State and Federal regulatory 
authorities (and even some operators) may have limited understanding of 
the location of those pipelines, thereby inhibiting damage prevention 
efforts as well as emergency response in the event of an excavation 
incident.

E. The Limits of PHMSA Regulation and State and Operator Initiatives in 
Reducing Intentional Methane Releases From Gas Pipeline Facilities

    In section 114 of the PIPES Act of 2020, Congress introduced 
requirements for operators of gas pipeline facilities to update their 
inspection and maintenance procedure to provide for the minimization of 
all releases of natural gas from their facilities--including 
intentional, vented emissions--in recognition of the significant 
environmental harm from those emissions. As described in section II.C, 
equipment venting, blowdowns, and other vented emissions of methane 
account for a large portion of the total methane emissions from U.S. 
natural gas pipeline facilities--particularly natural gas transmission 
pipelines. However, despite the significant environmental impact of 
those emissions, PHMSA and State pipeline safety regulations have 
largely avoided explicit restrictions on vented emissions. Moreover, 
the absence of robust reporting requirements for those emissions under 
part 191 inhibits PHMSA's ability to identify systemic issues.
    Part 191 does not require any reporting on intentional releases of 
methane or other gases (regardless of the total volume of gas emitted) 
unless a release causes death, hospitalization, or significant property 
damage. Similarly, part 192 and part 193 regulations do not require an 
operator to minimize intentional releases unless they could give rise 
to a public safety hazard.\188\ These regulatory gaps could permit 
situations such as pressure relief devices being configured to 
establish overly-conservative actuation setpoints--resulting in 
avoidable emissions being released because those pressure relief 
devices vent methane more frequently than necessary to maintain system 
pressure within safe operating bands. Incident reports and National 
Response Center (NRC) reports submitted to PHMSA for pressure relief 
device malfunctions provide a sense of the magnitude of potential 
emissions from improperly configured pressure relief devices: each 
incident can result in the release of millions of cubic feet of 
methane.
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    \188\ See, e.g., Sec. Sec.  192.169 and 192.617(a)(2) (requiring 
discharge piping for compressor station pressure relief devices and 
emergency shutdown systems vent to locations that would avoid public 
safety hazards) and 192.199(e) (requiring pressure relief and 
limiting devices have discharge stacks, vents, or outlet ports be 
located where gas can be discharged into the atmosphere without 
undue hazard).
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    Similar to voluntary leak detection and repair efforts, voluntary 
industry efforts to reduce emissions from blowdowns fall short in 
minimizing vented emissions. PHMSA is unaware of any industry-level, 
voluntary initiatives among operators of part 193 facilities to reduce 
vented emissions. And voluntary operator efforts among gas pipelines 
either parallel or directly invoke best practices recommended by the 
EPA's voluntary methane programs such as the Methane Challenge Program 
and the Natural Gas STAR programs.\189\ For the ``Best Management 
Practices'' option in the Methane Challenge Program, an operator can 
commit to cutting pipeline blowdown emissions by at least 50 percent by 
any of the following methods: \190\
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    \189\ EPA, ``Voluntary Methane Programs for the Oil and Natural 
Gas Industry,'' https://www.epa.gov/natural-gas-star-program (last 
accessed June 20, 2022). In 2018, members of the Interstate Natural 
Gas Association of America (INGAA) agreed to adopt voluntary 
commitments to minimize methane emissions from member transportation 
and storage assets, including a commitment to reduce emissions from 
blowdowns when repairs need to be made. The aforementioned EPA 
programs and two industry initiatives, the ONE Future Coalition and 
the Environmental Partnership, are featured prominently in the INGAA 
commitments. The full list of commitments is available on INGAA's 
website (https://www.ingaa.org/
File.aspx?id=38523&v=6553c6c8#:~:text=As%20part%20of%20our%20ongoing,
build%20a%20cleaner%20energy%20future) (last accessed July 20, 
2022).
    \190\ EPA, ``Natural Gas STAR Methane Challenge Program BMP 
Commitment Option Technical Document'' at 21 (May 2022).
---------------------------------------------------------------------------

     Routing gas to a compressor or capture system for 
beneficial use;
     Routing gas to a flare;
     Routing gas to a low-pressure system by taking advantage 
of existing piping connections between high- and low-pressure systems, 
temporarily resetting or bypassing pressure regulators to reduce system 
pressure prior to maintenance, or installing temporary connections 
between high and low-pressure systems; or
     Utilizing hot tapping, a procedure that makes a new 
pipeline connection while the pipeline remains in service, flowing 
natural gas under pressure, to avoid the need to blowdown gas.
    The voluntary industry emissions reduction efforts above cannot 
boast universal participation, but they hint at the potential for 
significant reductions in vented emissions if applied across all gas 
pipeline facility operators. In 2019 alone, a mere 8 participants in 
the EPA's Methane Challenge transmission pipeline blowdown mitigation 
program, operating 29 gas transmission pipeline facilities, reduced 
emissions by 1.9 million metric tons of CO2 equivalent 
estimated by calculation or measurement in accordance with 40 CFR part 
98, subpart W or, for non-subpart W facilities, an alternative 
method.\191\
---------------------------------------------------------------------------

    \191\ EPA, ``Methane Challenge Program Accomplishments,'' 
https://www.epa.gov/natural-gas-star-program/methane-challenge-program-accomplishments (last accessed July 20, 2022).
---------------------------------------------------------------------------

III. Federal Efforts To Address Climate Change by Reducing Methane 
Emissions

    The urgency of reducing methane emissions to stave off or avoid the 
worst

[[Page 31922]]

effects of climate change, coupled with the inability of existing 
Federal, State, and industry efforts to rise to that challenge, have 
catalyzed responses by the Federal legislative and executive branches 
to reduce unintentional and vented methane releases from gas pipeline 
facilities. Those efforts, which are discussed below, inform the 
regulatory amendments proposed in this NPRM.

A. The PIPES Act of 2020

    The PIPES Act of 2020, which was signed into law with broad 
bipartisan congressional and widespread industry and stakeholder 
support on December 27, 2020, directed a fundamental shift in PHMSA's 
regulation of gas pipeline facilities: environmental benefits would 
join public safety as a principal object of PHMSA regulation.\192\ 
Concerned in particular with the contribution of methane releases from 
natural gas pipelines to climate change,\193\ Congress included within 
that legislation three sections that would be implemented by this NPRM: 
sections 113, 114, and 118.
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    \192\ See 49 U.S.C. 60102(b)(5).
    \193\ See, e.g., 166 Cong. Rec. H7305 (Dec. 21, 2020) 
(memorializing a statement by Rep. Pallone that ``[t]his is a big 
win in the fight against climate change, along with the 
reauthorization of the Pipeline Safety Act, which reduces methane 
leaks.''); ``Press Release from Senate Commerce Committee Leaders 
Commending Passage of Pipeline Safety Legislation'' (Dec. 22, 2020), 
https://www.commerce.senate.gov/2020/12/committee-leaders-commend-passage-of-pipeline-safety-legislation (quoting Sen. Cantwell as 
stating ``This legislation also ensures that the latest technology 
will be used to detect and prevent costly methane leaks, which is 
especially important because methane leaks are a significant hazard 
and a major contributor to global warming.'').
---------------------------------------------------------------------------

    Section 113 of the PIPES Act of 2020 states that the Secretary of 
Transportation shall issue regulations that require operators of gas 
transmission pipeline facilities, gas distribution pipeline facilities, 
and certain regulated gas gathering pipelines in Class 2, Class 3, and 
Class 4 locations to conduct leak detection and repair programs to meet 
the need for gas pipeline safety and to protect the environment. Such 
regulations must include minimum performance standards that reflect the 
capabilities of commercially available advanced leak detection 
technologies that are appropriate for the type of pipeline, the 
location of the pipeline, the pipeline's material of construction, and 
the product transported by the pipeline. The leak detection and repair 
programs must be able to identify, locate, and categorize all leaks 
that are hazardous to human safety or the environment or that have the 
potential to become explosive or otherwise hazardous to human safety. 
The regulations must require the use of advanced leak detection 
technologies and practices through continuous monitoring on or along 
the pipeline, through periodic surveys with handheld equipment, 
equipment mounted on mobile platforms, or other commercially available 
technology. The regulations also must identify any scenarios where 
operators may use leak detection practices that depend on human senses, 
and include a schedule for repairing or replacing each leaking pipe, 
except for a pipe with a leak so small that it poses no potential 
hazard. Congress also expressly precluded the Secretary from reducing 
the frequency of surveys or extending the duration of leak repair or 
remediation timelines as required by PHMSA regulations on the date of 
enactment of the PIPES Act of 2020. Section 113 does not alter the 
Secretary's statutory authority to regulate gathering lines. Congress 
directed PHMSA to issue regulations implementing section 113 no later 
than December 27, 2021.
    Section 114 of the PIPES Act of 2020 adjusts the requirements for 
inspection and maintenance procedures. This self-executing provision of 
the statute requires that pipeline operators ensure their inspection 
and maintenance plans contribute to eliminating hazardous leaks of 
gases (not limited to natural gas) and minimizing releases of natural 
gas specifically from pipeline facilities; protect the environment; and 
address the replacement or remediation of pipelines (including cast-
iron, bare-steel, unprotected steel, wrought-iron, and certain plastic 
pipelines) that are known to leak based on material, design, or past 
operating and maintenance history. Operators had one year from the date 
of the enactment of the PIPES Act of 2020 (i.e., no later than December 
27, 2021) to update their inspection and maintenance plans to address 
these self-executing requirements.\194\
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    \194\ Section 114 also requires the Government Accountability 
Office to conduct a study to evaluate the procedures used by PHMSA 
and States when evaluating operators' inspection and maintenance 
plans, and subsequently issue a report regarding the findings of the 
study and recommendations for how to further minimize releases of 
natural gas from pipeline facilities without compromising pipeline 
safety. Additionally, the Secretary is to, not later than 18 months 
after the enactment of the PIPES Act of 2020, submit to Congress a 
report discussing the best available technologies or practices to 
prevent or minimize the release of natural gas, without compromising 
pipeline safety, when making planned repairs, replacements, or 
maintenance to a pipeline facility; or when intentionally venting or 
releasing natural gas, including when blowing down pipelines. The 
report must also discuss whether pipeline facilities can be 
designed, without compromising pipeline safety, to mitigate the need 
to intentionally vent natural gas.
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    Lastly, section 118 of the PIPES Act of 2020 amended the criteria 
set forth at 49 U.S.C. 60102(b)(5) governing issuance of any new 
rulemakings to elevate consideration of environmental benefits on par 
with other (e.g., public safety) anticipated benefits. That statutory 
amendment reinforced the environmental purpose of section 113 of the 
PIPES Act of 2020, as well as historical provisions (e.g., 49 U.S.C. 
60102(b)(1)(B)(ii) and (b)(2)(A)(3)) within the Federal Pipeline Safety 
Laws that authorize PHMSA to issue regulations acknowledging the 
environmental protection benefits from regulation of gas pipeline 
facilities.
    Gas pipeline operators and related trade associations applauded the 
passage through the Senate and later enactment of the PIPES Act of 2020 
as part of the Consolidated Appropriations Act of 2021 (Pub. L. 116-
260). For example, API released a statement in support of the Senate's 
passage of the legislation (S.2999) that became the PIPES Act of 2020, 
stating that the ``PIPES Act takes important steps to make pipelines 
safer for surrounding communities and the environment.'' \195\ 
Following enactment, INGAA described the PIPES Act of 2020 as a 
``historic piece of legislation'' that ``enhances pipeline safety, 
embraces the latest technologies, and aids in the further reduction of 
methane emissions.'' \196\ At the 2021 Public Meeting, AGA et al. 
expressed support for the PIPES Act of 2020 and initiatives that 
protect the public and the environment, noting that their members have 
committed to a range of initiatives to reduce methane emissions to 
achieve goals for addressing climate change.\197\
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    \195\ API, Press Release, ``API Statement of Senate Passage of 
PIPES Act (Aug. 6, 2020), https://www.api.org/news-policy-and-issues/news/2020/08/06/api-statement-on-senate-passage-of-pipes-act.
    \196\ INGAA, Press Release, ``INGAA Hails Passage of Historic 
Pipeline Safety Reauthorization Bill in 2021 Omnibus Package'' (Dec. 
21, 2020), https://www.ingaa.org/News/PressReleases/38353.aspx 
(quoting President and CEO of INGAA, Amy Andryszak, praising 
Congress's direction to PHMSA to update its regulations ``to reflect 
the latest technologies and practices [to] . . . both enhance safety 
and benefit the environment'').
    \197\ Sames, Cristina. Pipeline Leak Detection, Leak Repair, and 
Methane Emissions. AGA. May 5, 2021. Briefing materials, recordings, 
and transcripts of the 2021 Public Meeting are available on the web 
page for the meeting at https://primis.phmsa.dot.gov/meetings/MtgHome.mtg?mtg=152.
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B. Administration Efforts Confronting the Climate Crisis

    The U.S. Federal Government is taking aggressive action in response 
to climate change. During his first week in

[[Page 31923]]

office, President Biden established the National Climate Task Force, 
assembling leaders from across Federal agencies--including the 
Secretary of Transportation--to enable a whole-of-government approach 
to combatting the climate crisis.\198\ Essential in those efforts are a 
spectrum of regulatory actions being undertaken across the U.S. Federal 
Government to reduce methane emissions described in the U.S. Methane 
Emissions Reduction Action Plan published in November 2021.\199\ 
Parallel proposals by EPA and PHMSA to reduce methane emissions from 
natural gas infrastructure occupy a critical role in the 
Administration's whole-of-government strategy for tackling the climate 
crisis.
---------------------------------------------------------------------------

    \198\ White House, ``Fact Sheet: President Biden Takes Executive 
Actions to Tackle the Climate Crisis at Home and Abroad, Create 
Jobs, and Restore Scientific Integrity Across Federal Government'' 
(Jan. 27, 2021), https://www.whitehouse.gov/briefing-room/statements-releases/2021/01/27/fact-sheet-president-biden-takes-executive-actions-to-tackle-the-climate-crisis-at-home-and-abroad-create-jobs-and-restore-scientific-integrity-across-federal-government/.
    \199\ White House Office of Domestic Climate Policy, U.S. 
Methane Emissions Reduction Action Plan (Nov. 2021), https://www.whitehouse.gov/wp-content/uploads/2021/11/US-Methane-Emissions-Reduction-Action-Plan-1.pdf; White House Office of Domestic Climate 
Policy, Delivering on the U.S. Methane Emissions Reduction Action 
Plan (Nov. 2022), https://www.whitehouse.gov/wp-content/uploads/2022/11/US-Methane-Emissions-Reduction-Action-Plan-Update.pdf.
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1. Pertinent Executive Orders
    Several recent E.O.s direct PHMSA and other Federal agencies to 
undertake efforts to achieve substantial reductions of methane 
emissions from the oil and gas sector as soon as possible.
Executive Order 13990
    On January 20, 2021, the President signed E.O. 13990, titled 
``Protecting Public Health and the Environment and Restoring Science to 
Tackle the Climate Crisis'' \200\ announced the Administration's re-
commitment to environmental justice, science-based decision-making, 
protecting public health and the environment, and ensuring Federal 
agency actions account for the benefits of reducing climate pollution. 
Toward that end, E.O. 13990 directed all executive departments and 
agencies to immediately review and, as appropriate and consistent with 
applicable law, take action to address the promulgation of Federal 
regulations and other actions during previous years that conflict with 
these important national objectives, and to immediately commence work 
to confront the climate crisis.
---------------------------------------------------------------------------

    \200\ 86 FR 7037 (Jan 25, 2021).
---------------------------------------------------------------------------

Executive Order 14008
    On January 27, 2021, the President signed E.O. 14008, titled 
``Tackling the Climate Crisis at Home and Abroad.'' \201\ E.O. 14008 
puts ``the climate crisis at the center of U.S. foreign and domestic 
policy,'' with a focus on a multilateral approach to putting the world 
on a sustainable climate pathway and building resilience, both at home 
and abroad, against the impacts of climate change. Abroad, E.O. 14008 
expresses the Administration's intent for the United States to exercise 
its leadership to meet the climate challenge by recommitting to the 
Paris Agreement and engaging in international climate summits and 
forums. Domestically, E.O. 14008 outlines a plan to focus on an all-in 
approach that considers environmental justice for all communities 
(especially those that have been underserved in the past), creates 
clean energy jobs, and builds modern and sustainable infrastructure.
---------------------------------------------------------------------------

    \201\ 86 FR 7619 (Feb 1, 2021).
---------------------------------------------------------------------------

2. Renewal of U.S. Commitments to International Efforts To Address 
Climate Change
    Consistent with the instruction in E.O. 13990, the President 
returned the United States into the Paris Agreement on January 20, 
2021.\202\ The Paris Agreement is an agreement within the United 
Nations (UN) Framework Convention on Climate Change (UNFCCC) addressing 
climate change mitigation, adaptation, and finance, that was drafted 
throughout 2015 and was signed in 2016. The Paris Agreement was forged 
to help the world avoid catastrophic planetary warming and to build 
resilience around the world to the impacts from climate change that are 
occurring, with a long-term goal of keeping the rise in global average 
temperature to below 3.6 degrees Fahrenheit by reducing emissions of 
GHGs. To achieve these goals, article 4 of the Paris Agreement requires 
each party to prepare and maintain a ``nationally determined 
contribution'' of emissions reduction or mitigation targets once every 
5 years. As of October 2022, 194 members of the UNFCCC are parties to 
the agreement; the United States had withdrawn from the agreement in 
2020.
---------------------------------------------------------------------------

    \202\ https://unfccc.int/process-and-meetings/the-paris-agreement/the-paris-agreement. https://unfccc.int/process-and-meetings/the-paris-agreement/the-paris-agreement.
---------------------------------------------------------------------------

    Pursuant to section 102(e) of E.O. 14008, the United States also 
submitted a new Nationally Determined Contribution (NDC), on April 4, 
2021, after rejoining the Paris Agreement.\203\ In the NDC, the 
Administration announced an ambitious ``economy-wide target of reducing 
net greenhouse gas emissions by 50-52 percent below 2005 levels in 
2030.'' The NDC includes a specific commitment to address methane 
emissions by, among other efforts, ``plugging leaks from wells and 
mains and across the natural gas distribution infrastructure.'' \204\ 
The NDC notes that the United States aims to achieve these targets with 
a whole-of-government approach at the Federal level and ambitious 
innovation from State, local, and tribal governments, and private 
investment.
---------------------------------------------------------------------------

    \203\ UNFCCC, Nationally Determined Contribution Registry 
(Interim), ``The United States of America Nationally Determined 
Contribution'' (April 4, 2021).
    \204\ UNFCCC, Nationally Determined Contribution Registry 
(Interim), ``The United States of America Nationally Determined 
Contribution'' at 5 (April 4, 2021).
---------------------------------------------------------------------------

    The United States further reinforced its commitment to reducing 
methane emissions by joining the European Union and several other 
countries in committing to the Global Methane Pledge ahead of the 26th 
global climate summit (the 26th Conference of the Parties, or 
COP26).\205\ In its joint statement with the European Union, the Biden-
Harris Administration committed to direct the U.S. EPA and PHMSA to 
``reduce methane leakage from pipelines and related facilities,'' \206\ 
and announced that more than 100 countries had joined the Global 
Methane Pledge and a commitment to reduce the world's methane emissions 
30% from 2020 levels by 2030.\207\ The Administration has since 
released a U.S. Methane Emissions Reduction Action Plan detailing its 
comprehensive whole-of-government plan to reduce methane emissions 
through a combination of regulatory actions, financial incentives, 
increased transparency and data disclosure, and public and private

[[Page 31924]]

partnerships.\208\ The Administration continues to lead nations around 
the globe in methane reduction efforts, including by reconvening the 
Major Economies Forum on Energy and Climate (MEF) on multiple 
occasions. The President reconvened the MEF most recently on June 17, 
2022, to encourage participant countries to accelerate emissions 
reduction progress and provide a forum for participants to share the 
results of their Global Methane Pledge efforts.\209\ The regulatory 
requirements proposed in this NPRM would help align the United States 
with ongoing efforts from international partners to enhance methane 
mitigation requirements for gas pipeline infrastructure.\210\
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    \205\ ``Joint U.S.-EU Statement on the Global Methane Pledge'' 
(Oct. 11, 2021), https://www.state.gov/joint-u-s-eu-statement-on-the-global-methane-pledge/https://www.state.gov/joint-u-s-eu-statement-on-the-global-methane-pledge/.
    \206\ White House, ``Joint U.S.-E.U. Press Release on the Global 
Methane Pledge'' (Sept. 18, 2021), https://www.whitehouse.gov/briefing-room/statements-releases/2021/09/18/joint-us-eu-press-release-on-the-global-methane-pledge/.
    \207\ ``Fact Sheet: President Biden Tackles Methane Emissions, 
Spurs Innovations, and Supports Sustainable Agriculture to Build a 
Clean Energy Economy and Create Jobs'' (Nov. 2, 2021), https://www.whitehouse.gov/briefing-room/statements-releases/2021/11/02/fact-sheet-president-biden-tackles-methane-emissions-spurs-innovations-and-supports-sustainable-agriculture-to-build-a-clean-energy-economy-and-create-jobs/.
    \208\ White House Office of Domestic Climate Policy, U.S. 
Methane Emissions Reduction Action Plan (Nov. 2021), https://www.whitehouse.gov/wp-content/uploads/2021/11/US-Methane-Emissions-Reduction-Action-Plan-1.pdf.
    \209\ https://www.whitehouse.gov/briefing-room/statements-releases/2022/06/18/chairs-summary-of-the-major-economies-forum-on-energy-and-climate-held-by-president-joe-biden/. At this meeting of 
the MEF, the United States and the EU announced a new Global Methane 
Pledge Energy Pathway which ``aims to encourage all nations to 
capture the maximum potential of cost-effective methane mitigation 
in the oil and gas sector and to eliminate routine flaring as soon 
as possible, and no later than 2030.''
    \210\ For example, the European Union in December 2021 proposed 
legislation that would require member states to impose requirements 
that, at a minimum: (1) call for use of leak detection technologies 
with a minimum sensitivity comparable to those proposed in this 
rulemaking; (2) require leaks of at least 500 ppm to be immediately 
repaired or replaced and leaks of less than 500 ppm to be repaired 
or replaced within at least 3 months; and (3) create a default 
prohibition on all venting of methane (subject to certain 
exceptions). See European Parliament, ``EU Briefing--Fit for 55 
Package: Reducing Methane Emissions in the Energy Sector'' (Mar. 
2022), https://www.europarl.europa.eu/RegData/etudes/BRIE/2022/729313/EPRS_BRI(2022)729313_EN.pdf. Similarly, Canada in September 
2022 issued a national Methane Strategy outlining policy options for 
reducing methane emissions from natural gas pipeline infrastructure. 
See Envt. & Climate Change Canada, Faster and Further: Canada's 
Methane Strategy (Sept. 2022), https://publications.gc.ca/collections/collection_2022/eccc/En4-491-2022-eng.pdf.
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3. EPA's Proposed New Source Performance Standards and Emissions 
Guidelines for the Oil and Natural Gas Industry
    On November 15, 2021, the EPA proposed new source performance 
standards and emission guidelines for crude oil and natural gas 
facilities.\211\ This action was in response to the January 20, 2021, 
Executive Order titled ``Protecting Public Health and the Environment 
and Restoring Science to Tackle the Climate Crisis.'' The 2021 action 
proposed to update VOC and methane \212\ standards on the books for new 
sources (located at 40 CFR part 60, subparts OOOO and OOOOa),\213\ add 
new standards for new sources (which would be located at 40 CFR part 
60, subpart OOOOb), and establish the first nationwide Emission 
Guidelines for states to regulate methane emissions from existing 
sources (which would be located at 40 CFR part 60, subpart OOOOc).\214\ 
On December 6, 2022, in a supplemental proposal, EPA proposed further 
updates to its November 2021 proposal.\215\ The proposed standards are 
developed based on the EPA's determination of the ``best system of 
emissions reduction'' (BSER) under section 111 of the Clean Air Act. 
The EPA's proposed emission standards, including emissions monitoring, 
repair, and maintenance requirements, would apply to numerous types of 
facilities (including pneumatic controllers and pumps, storage vessels, 
and sweetening units amongst others) across a defined source 
category.\216\ Among the gas pipeline facilities within the scope of 
EPA's 40 CFR part 60 regulatory scheme are compressor stations on gas 
transmission pipelines and boosting stations on gas gathering 
pipelines.
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    \211\ EPA, ``Standards of Performance for New, Reconstructed, 
and Modified Sources and Emissions Guidelines for Existing Sources: 
Oil and Natural Gas Sector Climate Review,'' 86 FR 63110 (Nov. 15, 
2021).
    \212\ EPA regulates greenhouse gases expressed in the form of 
limitations on methane.
    \213\ 40 CFR part 60, subpart OOOO regulates VOC only. 40 CFR 
part 60, subpart OOOOa regulates both VOC and methane.
    \214\ The proposed Emission Guidelines would address methane 
only.
    \215\ EPA, ``Standards of Performance for New, Reconstructed, 
and Modified Sources and Emissions Guidelines for Existing Sources: 
Oil and Natural Gas Sector Climate Review,'' 87 FR 74702 (Dec. 6, 
2022) (EPA SNPRM).
    \216\ The EPA defines the Crude Oil and Natural Gas source 
category to mean (1) crude oil production, which includes the well 
and extends to the point of custody transfer to the crude oil 
transmission pipeline or any other forms of transportation; and (2) 
natural gas production, processing, transmission, and storage, which 
include the well and extend to, but do not include, the local 
distribution company custody transfer station. For purposes of EPA's 
proposed rulemaking, for crude oil, the EPA's focus is on operations 
from the well to the point of custody transfer at a petroleum 
refinery, while for natural gas, the focus is on all operations from 
the well to the local distribution company custody transfer station 
commonly referred to as the ``city-gate''.
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C. PHMSA Implementation of the PIPES Act of 2020

    PHMSA's efforts to implement requirements from the PIPES Act of 
2020 efforts dovetail with policy goals of the Biden-Harris 
Administration described above. This proposed rulemaking in particular 
is a key part of PHMSA's efforts to address these policy priorities and 
is referenced in the White House ``U.S. Methane Emissions Reduction 
Action Plan.'' \217\
---------------------------------------------------------------------------

    \217\ White House Office of Domestic Climate Policy, U.S. 
Methane Emissions Reduction Action Plan (Nov. 2021).
---------------------------------------------------------------------------

1. PHMSA's May 2021 Public Meeting
    PHMSA held a public meeting on May 5-6, 2021, (2021 Public Meeting) 
to provide stakeholder groups and members of the public an opportunity 
to share perspectives on improving gas pipeline methane leak detection 
and repair programs consistent with sections 113 and 114 of the PIPES 
Act of 2020. The agenda for the meeting included examining the sources 
of methane emissions from gas pipeline systems, the current regulatory 
requirements for managing fugitive and vented emissions, current leak 
detection and repair practices of the industry, and the use of advanced 
technologies and practices to reduce methane emissions from gas 
pipeline systems.
    Stakeholders were invited to submit written comments in connection 
with the 2021 Public Meeting. PHMSA received 7 comments from individual 
pipeline operators, leak detection technology service providers, public 
safety groups, and industry trade organizations, as summarized below. 
The meeting itself included presentations and panel discussions from 
representatives from PHMSA, EPA, NAPSR, EDF, PST, the United 
Association of Plumbers and Pipefitters, GPTC, AGA, American Public Gas 
Association, INGAA, GPA, Pipeline Regulatory Consultants, Gas 
Technology Institute, the Methane Emissions Technology Evaluation 
Center (METEC) at Colorado State University, QuakeWrap Inc., Bridger 
Photonics, Safetylics, ProFlex Technologies, ABB, the Federal Energy 
Regulatory Commission, and the National Association of Regulatory 
Utility Commissioners. Presentations, recordings, and transcripts from 
the meeting are available on PHMSA's public meeting web page.\218\ 
Certain comments made before, during, and after the meeting have been 
summarized and discussed throughout this NPRM.
---------------------------------------------------------------------------

    \218\ https://primis.phmsa.dot.gov/meetings/MtgHome.mtg?mtg=152.
---------------------------------------------------------------------------

2. June 2021 Advisory Bulletin
    PHMSA published an advisory bulletin on June 10, 2021, calling 
operators' attention to the self-executing requirements of section 114 
of the PIPES Act of 2020.\219\ The bulletin advised

[[Page 31925]]

operators of pipeline facilities to update their inspection and 
maintenance plans to address the elimination of hazardous leaks and 
minimize gas releases from their pipeline facilities, including 
intentional venting during normal operations. The bulletin also noted 
that, per the statutory mandate, operators must revise their plans to 
address the replacement or remediation of pipeline facilities that are 
known to leak based on their material, design, or past operating and 
maintenance history. The advisory bulletin noted that the PIPES Act of 
2020 requires pipeline facility operators to complete these updates by 
December 27, 2021.
---------------------------------------------------------------------------

    \219\ PHMSA, ``Pipeline Safety: Statutory Mandate to Update 
Inspection and Maintenance Plans to Address Eliminating Hazardous 
Leaks and Minimizing Releases of Natural Gas from Pipeline 
Facilities,'' 86 FR 31002 (June 10, 2021) (ADB-2021-01).
---------------------------------------------------------------------------

3. February 2022 PHMSA Webinar Addressing Inspection of Operators' 
Plans To Eliminate Hazardous Leaks, Minimize Releases of Methane, and 
Remediate or Replace Leak-Prone Pipe
    On February 17, 2022, PHMSA held an informational public webinar 
reviewing the requirements for pipeline operator inspection and 
maintenance plans introduced by section 114 of the PIPES Act of 
2020.\220\ This webinar was informational, with attendees having the 
opportunity to submit written comments to the public meeting docket. 
More than 1,500 individuals registered for the public webinar, 
including representatives from the gas gathering, transmission, and 
distribution sectors. During the webinar, PHMSA discussed key elements 
of the new section 114 requirements and reviewed the applicable 
timelines for the actions required under section 114. PHMSA also 
discussed its planned approach to inspection of operators' programs and 
procedures to reduce methane emissions and replace or remediate leak-
prone pipes.
---------------------------------------------------------------------------

    \220\ PHMSA's presentation during this webinar and a recording 
of the webinar meeting are available on PHMSA's public meeting web 
page at https://primis.phmsa.dot.gov/meetings/MtgHome.mtg?mtg=159.
---------------------------------------------------------------------------

IV. Summary of Proposals

A. Leakage Survey and Patrol Frequencies and Methodologies

    Existing Federal regulations in subpart M of part 192 are focused 
primarily on avoiding risks to public safety posed by of instantaneous, 
large-volume releases or accumulated gas from gas pipelines, with less 
attention given to environmental harms from methane leaks to the 
atmosphere and releases of other flammable, toxic or corrosive gases. 
Part 192 imposes leakage survey and patrol periodicities based on the 
magnitude and probability of those public safety risks (via the proxies 
of class location, business districts, and potential impact radius), 
with operators required to conduct leakage surveys only once per 
calendar year but with an interval between surveys not to exceed 15 
months for most gas transmission pipelines, offshore gathering, 
distribution pipelines inside of business districts, and some onshore 
part-192 regulated gathering pipelines; distribution pipelines outside 
of business districts are obliged to conduct surveys only once every 
five years. Sections 192.706 and 192.723 outline requirements for 
leakage surveys (including periodicity) on gas transmission and gas 
distribution pipelines, respectively, and all offshore, Types A and B 
gas gathering and certain Type C gathering pipelines must follow the 
Sec.  192.706 leakage survey requirements for gas transmission lines. 
Those existing prescribed periodicities are described in further detail 
below.
    Current regulations do not specify what technologies or equipment 
must be used in the performance of leakage surveys, and most gas 
gathering and transmission pipelines are exempt from odorization 
requirements that could help identify leaks. Currently, leakage surveys 
on all distribution lines and certain unodorized gas transmission and 
gathering pipelines must be performed using ``leak detection 
equipment,'' but this term is not currently defined in part 192. PHMSA 
has historically declined to establish technology or performance 
standards regarding leak detection equipment. Leakage surveys on 
transmission pipelines in Class 1 or Class 2 locations or Class 3 and 
Class 4 locations that are odorized can rely entirely on human senses 
such as smell or sight. This NPRM proposes to set more specific 
technical standards for leak detection equipment used for leakage 
surveys, and these are described in detail in section IV.B of this 
NPRM.
    PHMSA regulations currently require only annual right-of-way 
patrols on most gas transmission, offshore gathering, and Type A-
regulated onshore gathering lines. Patrols are visual surveys and do 
not require the use of any equipment. Sections 192.705 and 192.721 
define right-of-way patrolling requirements for gas transmission, (as 
well as offshore and Type A gathering), and distribution pipelines, 
respectively. While offshore and Type A gas gathering pipelines are 
subject to the same requirements as transmission lines, Types B and C 
gathering pipelines are not subject to any patrolling requirements. 
Patrols are typically reliant on human senses (vision, sound, or scent) 
and do not require the use of leak detection equipment (although 
operators may incorporate leak detection equipment at their 
discretion). An operator may combine a patrol with a leakage survey, 
provided their procedures include both a visual survey of the right-of-
way and a leakage survey with leak detection equipment. Patrols can 
detect unsafe conditions that may indicate a current or future leak or 
incident. For example, visual right of way patrols can identify 
construction activity that signifies a potential excavation damage 
threat, earth and water movement that may indicate a natural force 
damage threat, or population growth that may indicate change in class 
location, change in HCA or Moderate Consequence Area status, and higher 
potential consequences of an incident. Patrols can also detect certain 
leaks by odor, by detecting dead vegetation, or by other indicia (e.g., 
bubbles from an offshore, submerged pipeline). However, those 
approaches entail their own limitations; for example, reliance on smell 
would not be effective unless the gas contains odorants and vegetation 
surveys are only effective in certain soil and climate conditions (and 
completely ineffective in areas with no or sparse vegetation such as 
paved areas or deserts), and a noticeable impact on vegetation from a 
leak may lag substantially behind the leak's emergence.
    The limitations of PHMSA's existing leakage survey and patrol 
regulations thus currently allow for extended periods of time during 
which leaks can degrade into catastrophic integrity failures, allow gas 
to build up and ignite, or emit a substantial amount of methane or 
other (flammable, toxic or corrosive) gases to the environment. For gas 
gathering lines conveying unprocessed natural gas, the risks to public 
safety and the environment from infrequent (or non-existent) leak 
survey requirements are particularly acute as any leaks releasing VOCs 
and HAPs, such as benzene, and corrosive materials entrained with the 
unprocessed natural gas can expedite degradation of pipeline integrity. 
And leaks of toxic or corrosive gases from other gas pipeline 
facilities can adversely affect environmental resources. The 
environmental impacts of gas pipeline leaks and the estimated 
environmental and public safety benefits of the requirements proposed 
herein are discussed in further detail in section 5 of the Preliminary 
RIA for this NPRM, available in the rulemaking docket. Further, the 
widespread use of human senses in leakage surveys is a missed 
opportunity to leverage existing

[[Page 31926]]

commercially available leak detection technology to protect against 
these risks to public safety and the environment by ensuring that leaks 
are identified and addressed in a timely manner. In addition to the 
public safety and human health risks of undetected methane leaks, long 
intervals between surveys also result in increased emissions of methane 
or other flammable and toxic gases. For example, in a presentation on 
the Fugitive Emissions Abatement Simulation Toolkit (FEAST) model at 
the 2021 EPA Methane Detection Technology Workshop, modeling based on 
controlled tests and field evaluations demonstrated that at a given 
detection threshold, survey frequency is directly proportional to 
fugitive emissions reductions.\221\ While the modeling shows decreasing 
emissions abatement returns to increasing survey frequency, large drop-
offs begin to appear only after semiannual OGI surveys.
---------------------------------------------------------------------------

    \221\ Ravikumar, Arvind Ph.D. ``FEAST-Based Evaluation of 
Methane Leak Detection and Repair Programs Using New Technologies.'' 
EPA Methane Detection Technology Workshop (August 24, 2021). https://www.epa.gov/controlling-air-pollution-oil-and-natural-gas-industry/epa-methane-detection-technology-workshop. Day 2 at 1:33:50.
---------------------------------------------------------------------------

    PHMSA therefore proposes to strengthen minimum leakage survey 
frequencies for gas transmission and gathering pipelines located in 
HCAs, aboveground offshore gas transmission and gathering pipelines, 
distribution pipelines outside of business districts, and distribution 
pipelines at a high risk of leakage. PHMSA also proposes to introduce 
patrolling requirements for Type B and Type C gathering pipelines and 
to increase the minimum patrolling frequency for all gas transmission, 
offshore gathering, and Type A regulated onshore gas gathering 
pipelines. Finally, while all operators may supplement instrumented 
leakage surveys with visual and other sensory survey techniques, PHMSA 
proposes to limit the exclusive use of human senses for leakage surveys 
to submerged offshore gas transmission and submerged offshore gas 
gathering pipelines and, subject to notification to and review by 
PHMSA, onshore gas transmission and regulated onshore gas gathering 
pipelines in Class 1 and Class 2 locations outside of HCAs. These 
amendments would ensure timely detection of leaks. The proposed changes 
to patrolling frequency would also increase the likelihood that 
conditions that could result in leaks, potentially fatal incidents, or 
damage that could result in shutdowns and maintenance-related releases 
of methane to the atmosphere are detected.
    These proposals (and all other proposed amendments to parts 191 and 
192) apply generally to pipeline transportation of any ``gas,'' defined 
in Sec. Sec.  191.3 and 192.3 as ``natural gas, flammable gas, or gas 
which is toxic or corrosive.'' Although natural gas pipelines 
constitute the vast majority of part 192-regulated gas pipeline mileage 
today, the requirements for ``gas'' pipelines in parts 191 and 192 
apply equally to pipelines transporting other gases, including over 
1,500 miles of hydrogen gas pipelines in operation today.\222\ Unless 
otherwise specified in the proposed amendments, the proposals in this 
NPRM apply the same requirements to hydrogen gas pipelines (and other 
gas pipelines) as to natural gas pipelines. PHMSA invites comment on 
whether, within a final rule in this proceeding, there would be value 
in adopting hydrogen gas pipeline-specific provisions (in lieu of or in 
addition to the provisions proposed herein). Comments on this question 
are especially helpful if they address the potential safety and 
environmental benefits and potential costs of a particular approach, 
including whether that approach would be technically feasible, cost-
effective, and practicable.
---------------------------------------------------------------------------

    \222\ See PHMSA Interpretation Response Letter No. PI-92-030 
(July 14, 1992) (noting PHMSA regulates hydrogen pipelines under 
part 192); PHMSA, ``Presentation of Vincent Holohan for Workgroup#4: 
Hydrogen Network Components at December 2021 Meeting'' at slide 11 
(Dec. 1, 2021), https://primis.phmsa.dot.gov/meetings/FilGet.mtg?fil=1227.
---------------------------------------------------------------------------

    PHMSA has not proposed in this NPRM to establish minimum leakage 
survey frequencies or leak detection equipment requirements for UNGSFs. 
This approach is consistent with current PHMSA regulations at Sec.  
192.12, which do not require UNGSFs perform periodic leakage surveys 
with leak detection equipment but rather oblige operators of UNGSFs to 
perform an integrity assessment of each reservoir, cavern, and well as 
often as necessary (but with a maximum interval between assessments 
that does not exceed 7 years). Additionally, consensus industry 
standards \223\ incorporated by reference in Sec.  192.12 include 
recommendations and requirements for periodic UNGSF reservoir and 
wellsite inspection and monitoring. However, PHMSA invites comment on 
whether, within a final rule in this proceeding, there would be value 
in prescribing leakage survey frequency and leak detection equipment 
requirements for UNGSFs in Sec.  192.12. Comments on this question are 
especially helpful if they address the potential safety and 
environmental benefits and potential costs of a particular approach, 
including whether that approach would be technically feasible, cost-
effective, and practicable.
---------------------------------------------------------------------------

    \223\ API Recommended Practice 1170, Design and Operation of 
Solution-Mined Salt Caverns Used for Natural Gas Storage--First 
Edition (July 2015); API Recommended Practice 1171, Functional 
Integrity of Natural Gas Storage in Depleted Hydrocarbon Reservoirs 
and Aquifer Reservoirs--First Edition (Sept. 2015).
---------------------------------------------------------------------------

1. Distribution--Sec.  192.723
    Section 192.723 outlines the current requirements for leakage 
surveys on gas distribution systems. Leakage surveys on distribution 
pipelines must be performed using leak detection equipment. Leakage 
surveys in business districts must be performed at least once each 
calendar year, with an interval between surveys not to exceed 15 
months. On distribution pipelines outside of business districts that 
are not cathodically protected and where electrical surveys for 
corrosion are impractical (i.e., bare steel, unprotected steel, and 
cast-iron systems), leakage surveys must be performed once every 3 
calendar years, with an interval between surveys not to exceed 39 
months. All other portions of a distribution system outside of business 
district must currently be surveyed once every 5 calendar years at 
intervals not exceeding 63 months. The term ``business district'' is 
not defined. PHMSA invites comment on potential criteria for defining 
the boundaries of a business district for potential inclusion within a 
final rule in this proceeding. Comments on these potential criteria are 
especially helpful if they address the potential safety and 
environmental benefits and potential costs of a proposed or alternative 
approach, including whether each proposal would be technically 
feasible, cost-effective, and practicable.
    As described in section III.C, fugitive emissions from leaks 
represent the vast majority of total methane emissions from natural gas 
distribution systems. However, the current Sec.  192.723 neither 
articulates minimum performance standards for leak detection equipment 
nor prescribes a particular technology to ensure that all leaks are 
identified during leakage surveys on distribution pipelines. PHMSA 
therefore proposes several regulatory amendments that would increase 
the frequency and effectiveness of leakage surveys to identify and 
repair leaks on gas distribution pipelines. First, PHMSA proposes that 
leakage surveys be incorporated within operator ALDPs meeting the 
minimum performance standards proposed in this NPRM and any detected 
leaks be graded and repaired consistent with the grading

[[Page 31927]]

framework in this NPRM (each discussed further in section IV.B). These 
proposals would better address the leading causes of methane emissions 
from gas distribution systems by ensuring that leaks are detected and 
repaired in a timely manner. Second, PHMSA proposes more frequent 
leakage surveys to promote earlier detection and repair of leaks, 
thereby improving the environment by reducing emissions from those 
leaks, and improving the likelihood that leaks are detected before they 
adversely impact public safety.
    As described earlier, distribution leakage surveys are currently 
required once every 1, 3, or 5 calendar years, depending on the 
location and design of the pipeline. The 5-year maximum leakage survey 
interval allows even leaks hazardous to people or property that must be 
``repaired promptly'' under current Sec.  192.703 to remain undetected 
for up to 5 years, often placing the burden on the general public to 
detect and report potentially hazardous leaks via odor calls. In 
addition to the potential hazard to public safety and human health, an 
undetected leak will continue to emit methane to the environment until 
it is detected and repaired. PHMSA therefore proposes to eliminate the 
5-year survey frequency tier by moving leakage surveys outside of 
business districts from at least once every 5 years into the next 
frequency category: at least once every 3 calendar years, with an 
interval between surveys not to exceed 39 months. Leakage surveys 
inside of business districts would still be required annually. This 
proposal would increase the frequency of leakage surveys on all 
distribution pipelines outside of business districts, consistent with 
the environmental and public safety risks of any leaks, while ensuring 
that operators continue to prioritize frequency of surveys inside of 
business districts where there is a higher risk to people and property. 
Combined with the repair requirements proposed in the new Sec.  
192.760, which proposes a maximum repair timeline of 24 months for 
grade 3 leaks, this ensures that operators repair all leaks prior to 
their next distribution leakage survey, preventing continued growth in 
the backlog of unrepaired leaks. Some States have adopted similar 
standards for leakage surveys outside of business districts, for 
example the Commonwealth of Massachusetts requires leakage surveys 
outside of ``principal business districts'' at least once every 24-
months.\224\
---------------------------------------------------------------------------

    \224\ 220 Code of Massachusetts Regulations 101.06(21)(b).
---------------------------------------------------------------------------

    Similarly, due to the increased environmental and safety risks of 
distribution mains and service lines that are either without cathodic 
protection, or known to leak based on material, design or past 
operating and maintenance history, PHMSA proposes to require that 
operators perform a leakage survey at least once each calendar year 
with the interval between surveys not to exceed 15 months, mirroring 
the high-priority survey frequency for unprotected pipelines and 
pipelines inside of business districts. Currently, such pipelines mut 
be assessed at the lowest frequencies: once every 3 calendar years for 
cathodically unprotected distribution pipelines outside of business 
districts; once every 5 calendar years for all other distribution 
pipelines outside of business districts; or once every calendar year 
for all distribution pipelines within business districts. As with 
distribution pipelines outside of business districts, some States have 
also adopted enhanced leak survey requirements for leak-prone pipe. For 
example, the State of Kansas requires annual leakage surveys for 
cathodically unprotected steel mains and ductile iron mains in class 2, 
3, or 4 locations.\225\ Consistent with section 114 of the PIPES Act of 
2020, materials known to leak include cast iron, unprotected steel, 
wrought iron, and historic plastics with known issues. As described in 
the emissions discussion in section II.C, certain materials are 
responsible for a disproportionate amount of emissions from leaks, with 
distribution mains composed of such materials being particularly 
significant sources of emissions. PHMSA's proposal seeks to increase 
the scrutiny of distribution systems outside of business districts at a 
high risk of leakage by decreasing survey intervals and targeting 
materials at a high risk of leakage. PHMSA's proposal also contemplates 
that distribution pipeline operators would retain the option to 
establish more frequent leakage surveys than proposed herein within 
their operations and maintenance procedures or DIMP plans.
---------------------------------------------------------------------------

    \225\ Kansas Administrative Regulations 82-11-4(b)(34)(b)(2)(i).
---------------------------------------------------------------------------

    The following categories of distribution pipelines outside of 
business districts would be subject to the proposed annual survey 
requirement:
     Cathodically unprotected pipelines on which electrical 
surveys are impracticable, typically bare and unprotected distribution 
lines;
     Any distribution pipeline protected by a distributed anode 
system where the cathodic protection survey under Sec.  195.463 showed 
a deficient reading; and
     Pipelines known to leak based on the material (including, 
but not limited to, cast iron, unprotected steel, wrought iron, and 
historic plastics with known issues), design, or past operating and 
maintenance history of the pipeline.
    PHMSA expects that, in determining whether a plastic pipe material 
is a ``historic plastic with known issues'' making it at high risk of 
leaks, operators should consider PHMSA and State regulatory actions and 
industry technical resources identifying systemic integrity issues on 
plastic pipe made from particular materials; or manufactured at 
particular times or by particular companies, or fabricated and 
installed pursuant to particular processes. By way of illustration, 
PHMSA issues advisory bulletins cautioning operators regarding the 
susceptibility of certain historic plastics to systemic integrity 
issues. In 2007, in response to NTSB findings and data collection 
performed by the Plastic Pipe Database Committee (PPDC), PHMSA issued 
Advisory Bulletin ADB-07-01.\226\ That advisory bulletin called 
operators' attention to cracking issues on pipe and components 
manufactured by Century Utility Products, Inc.; low-ductile inner wall 
``Aldyl A'' piping manufactured by Dupont before 1973; polyethylene gas 
pipe made from PE 3306 resin; Delrin insert tap tees; and caps made of 
Celcon (polyactal) on Plexco service tees. Similarly, State pipeline 
safety regulatory actions, PHMSA pipeline failure investigation 
reports, and NTSB findings can inform operator determinations whether 
historic plastic pipe is at a high risk of leakage. Industry efforts 
and resources are another resource for operators in determining whether 
historic plastic pipe is known to leak. For example, the PPDC publishes 
data submitted by program participants that incorporates information 
regarding investigations of materials of concern or potential 
concern.\227\ PHMSA expects that these and other authoritative 
resources--coupled with an operator's own design expertise and 
operational and maintenance history--would be adequate for a reasonably 
prudent operator to determine whether the particular plastic pipe in 
its distribution systems is at a high risk of leakage.

[[Page 31928]]

PHMSA invites comment on the value of either explicitly listing (either 
within part 192 or within periodically-issued implementing guidance) 
historic plastics known to leak, or deleting the scope qualification 
``historic'' from the proposed regulatory text, for the purposes of the 
proposed annual survey requirement or for replacement under section 114 
of the PIPES Act of 2020. Comments on this question are especially 
helpful if they address the potential safety and environmental benefits 
and potential costs of a particular approach, including whether that 
approach would be technically feasible, cost-effective, and 
practicable.
---------------------------------------------------------------------------

    \226\ ``Pipeline Safety: Updated Notification of Susceptibility 
to Premature Brittle-Like Cracking of Older Plastic Pipe-Advisory 
Bulletin ADB-07-01,'' 72 FR 51301 (September 6, 2007).
    \227\ APGA, ``Plastic Pipe Database Collection Initiative,'' 
https://www.apga.org/programs/plasticpipedata (last accessed Dec. 
20, 2022).
---------------------------------------------------------------------------

    PHMSA further proposes to require that operators perform a leakage 
survey of a distribution pipeline segment after extreme weather events 
or land movement occur that could damage that segment. This survey must 
be completed within 72 hours of the cessation of the event, described 
as the time when the location can be safely accessed by operator 
personnel, or alternatively, within 72 hours of when the pipeline is 
returned to service. Such a survey could qualify as a periodic survey, 
and therefore reset the one- or three-year clock until the next 
required periodic survey. Separately, PHMSA proposes to require 
operators to investigate existing leaks when ground freezing and other 
changes in environmental conditions (such as heavy rain or flooding-
inducing ground subsidence, erosion, or the installation of new 
pavement) has occurred that could affect gas venting or migration to 
nearby buildings. The required investigation would include conducting a 
leakage survey for possible gas migration, but said survey would not 
qualify as a periodic survey and would not reset the one- or three-year 
clock until the next required periodic survey. Each of those changes in 
environmental conditions can place new stresses on pipeline integrity 
or can affect how and where gas vents from or migrates through the 
ground. Therefore, each can cause new leaks or exacerbate or reveal 
pre-existing leaks on distribution pipelines. These requirements are 
designed to ensure prompt evaluation of whether environmental changes 
have exacerbated existing leaks in a way that creates increased risk to 
public safety and the environment. PHMSA invites comment on whether to 
require assessments prior to extreme weather events in order for 
operators to prepare for and prevent resulting leaks.\228\ Comments on 
this question are especially helpful if they address the potential 
safety and environmental benefits and potential costs of a particular 
approach, including whether that approach would be technically 
feasible, cost-effective, and practicable.
---------------------------------------------------------------------------

    \228\ See, e.g., EPA's notice of proposed rulemaking titled 
``Accidental Release Prevention Requirements: Risk Management 
Programs Under the Clean Air Act; Safer Communities by Chemical 
Accident Prevention,'' 87 FR 53556 (Aug. 31, 2022) (proposing to 
require, under the Clean Air Act Risk Management Program, that 
industrial chemical facilities evaluate ways to address natural 
disasters and consider steps to prevent releases that may result, 
even before such events occur).
---------------------------------------------------------------------------

    The proposed amendments to gas distribution pipeline leakage survey 
requirements are summarized in the table below.

            Summary of Distribution Leakage Survey Amendments
------------------------------------------------------------------------
            Facility                   Existing            Proposed
------------------------------------------------------------------------
Outside of Business Districts...  5 years not to      3 years not to
                                   exceed 63 months.   exceed 39 months.
Pipelines known to leak           3 years not to      Annually, not to
 (cathodically unprotected pipe    exceed 39 months.   exceed 15 months.
 in existing Sec.   192.723).
Inside Business Districts.......  Annually, not to    No change.
                                   exceed 15 months.
                                 ---------------------------------------
Other Proposals.................  --After environmental changes that can
                                   affect gas migration.
                                  --Following extreme weather events.
------------------------------------------------------------------------
Note: The most frequent survey would apply.

    PHMSA expects its proposed amendments to leakage survey practices 
would be reasonable, technically feasible, cost-effective, and 
practicable for affected gas distribution operators. As explained 
above, operators are already subject to prescriptive periodic leakage 
surveys and patrols, and individual operators may have more demanding 
requirements specified within their DIMP plans or as a function of 
state-imposed requirements; affected operators also have the option to 
sync their patrol and leakage survey requirements to minimize 
compliance burdens (provided that the operator includes both a visual 
survey of the right-of-way and a leakage survey with leak detection 
equipment). PHMSA's proposed amendments would merely increase 
prescribed frequencies within Federal regulation as a function of 
factors (presence of cathodic protection; extreme weather events; 
material composition, operating and maintenance history) probative of 
leak susceptibility--and by extension, risks to public safety and the 
environment. PHMSA further notes that, insofar as those factors 
employed in the NPRM as bases for increased leakage survey frequency 
are widely understood to be potential threats to the integrity of gas 
distribution pipelines, they are among the phenomena that reasonably 
prudent operators would evaluate, and potentially adopt mitigation 
measures to address, in ordinary course when implementing current DIMP 
requirements to protect public safety from releases of (natural, 
flammable, toxic, or corrosive) pressurized gases from their pipelines 
and minimize loss of commercially valuable commodities. Additionally, 
operators would have flexibility (as appropriate for their needs and 
their pipelines' operational characteristics and environment) in 
choosing between commercially available, advanced leakage detection 
equipment satisfying the performance standards proposed in this NPRM 
for use in those leakage surveys. Viewed against those considerations 
and the compliance costs estimated in the Preliminary RIA, PHMSA 
expects its proposed amendments will be a cost-effective approach to 
achieving the commercial, public safety and environmental benefits 
discussed in this NPRM and its supporting documents. Lastly, the 
proposed compliance timelines--based on an effective date of the 
proposed requirements six months after the publication date of a final 
rule in this proceeding--would provide operators ample time to 
implement requisite changes in their leakage survey practices and 
manage any related compliance costs.
    In the Preliminary RIA, PHMSA considers an alternative where the 5-

[[Page 31929]]

year survey interval outside of business districts is maintained for 
plastic pipe distribution pipelines without known leak issues. This 
alternative is not being proposed because while recent-vintage plastic 
pipe is understood to leak less than cast iron and bare steel, some 
studies indicate that plastic piping systems may be leaking more than 
previously thought.\229\ PHMSA invites comment concerning the value of 
more or less frequent leakage surveys of plastic pipe systems, as well 
as potential means to identify plastic pipe known to leak (e.g., via a 
surveillance or sampling program) for inclusion within a final rule in 
this rulemaking proceeding. Likewise, PHMSA seeks comment on the 
alternative considered in the Preliminary RIA where distribution mains 
would be required to be surveyed annually; typically, mains are likely 
to be more accessible to pipeline operators than service lines crossing 
private property and may therefore be more convenient to survey. 
Comments on these questions are especially helpful to PHMSA when they 
are supported by research or operational experience with leaks from 
plastic pipe systems or distribution mains (as applicable), along with 
the potential safety and environmental benefits and potential costs of 
a particular approach (including whether that approach would be 
technically feasible, cost-effective, and practicable).
---------------------------------------------------------------------------

    \229\ Weller et al., 2020, for example.
---------------------------------------------------------------------------

2. Transmission and Gathering--Sec. Sec.  192.9, 192.705, and 192.706
    Section 192.706 currently requires gas transmission and Types A and 
B gathering pipelines that are not odorized to be surveyed with leak 
detection equipment at least twice each calendar year in Class 3 
locations, and at least four times each calendar year in Class 4 
locations. All other gas transmission, offshore gathering, Type A and 
Type B gathering, and certain Type C gathering pipelines must be 
surveyed once each calendar year. For these annual surveys, PHMSA does 
not require leak detection equipment on gas transmission and offshore 
gas gathering pipelines; however, Sec.  192.9 requires the use of leak 
detection equipment for leakage surveys on Type B and Type C gas 
gathering pipelines. Section 192.705 specifies frequencies for right-
of-way patrols along gas transmission, offshore gathering, and Type A 
gathering pipelines; Types B and C gathering lines are not required to 
conduct right-of-way patrols by Sec.  192.705.
    Consistent with section 113 of the PIPES Act of 2020, PHMSA 
proposes to require the use of leak detection equipment and practices 
meeting the ALDP standard in proposed Sec.  192.763 (see section IV.B) 
for leakage surveys on most onshore gas transmission and Types A, B and 
C gathering pipelines. Leakage survey by human or animal senses would 
be permitted for offshore gas transmission and offshore gathering 
pipelines. Because leaks on submerged offshore pipelines are visibly 
conspicuous due to bubbles or a sheen of gas condensate on the water's 
surface, PHMSA is not proposing to require leak detection equipment be 
used for leakage surveys of submerged offshore pipelines, including 
platform risers up to the waterline. However, offshore platform piping 
and riser piping above the waterline would be subject to the same 
equipment and survey requirements as onshore gas transmission 
pipelines. Leakage surveys for onshore pipelines would be permitted 
without the use of leak detection equipment (i.e., with human senses or 
animal senses) only for gas transmission and Types A, B, or C gathering 
pipelines in non-HCA, Class 1 and Class 2 locations, and then only with 
prior notification and review by PHMSA pursuant to Sec.  192.18. Visual 
surveys and other survey methods depending exclusively on human or 
animal senses would only be authorized if the operator can demonstrate 
through tests and analyses included in the notification that the survey 
method would be effective to meet the ALDP performance standard 
proposed in Sec.  192.763(b) or (c). For example, a visual vegetation 
survey would need to include procedures to ensure effective detection, 
such as ensuing the location of a buried pipeline is determined before 
a survey and performing vegetation surveys on foot rather than at a 
distance from a vehicle or aircraft, and would not be approved in areas 
where vegetation is absent. The notification must also include the 
survey procedures and qualifications for surveyors. Leaks detected on 
gas transmission, offshore gathering, and Types A, B, and C gathering 
pipelines would need to be graded and repaired consistent with the 
requirements proposed in this NPRM (see section IV.C). PHMSA welcomes 
comments and data on the efficacy of the exclusive use of human senses 
for leakage surveys, particularly on submerged offshore gas 
transmission pipelines, submerged offshore gas gathering pipelines, 
onshore gas transmission pipelines, and regulated onshore gas gathering 
pipelines (for potential inclusion within a final rule in this 
proceeding). Comments and data on this question are especially helpful 
to PHMSA when they are supported by research or operational experience 
with the exclusive use of human senses for leakage surveys, along with 
the potential safety and environmental benefits and potential costs of 
a particular approach (including whether that approach would be 
technically feasible, cost-effective, and practicable).
    As explained in section II.C above, leaks from natural gas 
transmission line pipe are not as significant a source of methane 
emissions compared with venting, blowdowns, and leaks from compressor 
stations and other aboveground equipment. However, as explained above 
in connection with leakage surveys on gas distribution lines, any leaks 
of methane contribute to climate change and can entail public safety 
risks--risks that are each more acute for gas transmission pipelines, 
which generally operate at higher pressures and capacity than 
distribution pipelines and are usually not odorized. Further, leaks 
from gas pipeline facilities transporting other flammable, toxic, or 
corrosive gases can entail significant public safety and environmental 
consequences. PHMSA therefore proposes, to support more timely 
detection and repair of leaks that pose a safety hazard, an increase in 
the minimum leakage survey frequencies for each of the following, 
calibrated based on a pipeline's proximity to occupied buildings or 
HCAs: for gas transmission, offshore gathering, and Type A, B, and C 
gathering pipelines located in HCAs from once each calendar year to 
twice each calendar year (at intervals not exceeding 7\1/2\ months) if 
within a Class 1, Class 2, or Class 3 location; and for gas 
transmission and Types A or B gathering pipelines located within Class 
4 locations within HCAs, from once each calendar year to four times 
each calendar year (at intervals not exceeding 4\1/2\ months). For gas 
transmission and Type A or B gas gathering pipelines that are 
(consistent with the proposed revisions herein to Sec.  192.625) not 
odorized, more frequent leak surveys would continue to be required to 
account for the greater risks to public safety from their proximity to 
occupied buildings: no less than twice each calendar year (at intervals 
not exceeding 7\1/2\ months) for pipelines in Class 3 locations, and no 
less than four times each calendar year (at intervals not exceeding 
every 4\1/2\ months) in Class 4 locations. Leaks on gas transmission 
pipelines, especially in Class 3 and Class 4 locations, would also be 
subject to more stringent grading requirements

[[Page 31930]]

in the proposed leak grading and repair requirements described in 
section IV.C.
    As explained in section II.C above, fugitive methane emissions from 
natural gas compressor stations on gas transmission and gas gathering 
pipelines comprise a significant share of fugitive emissions from those 
facilities. Other pipeline facilities with relatively complex design 
and configuration--such as valve sites (including the valve components, 
flanges, and tie-ins with line pipe), in-line instrument (ILI) 
launchers and receivers, and tanks--have fugitive emissions profiles 
better resembling compressor stations than line pipe. PHMSA therefore 
proposes more frequent leakage surveys for each of those facilities on 
gas transmission, offshore gathering, and Types A, B, and C gathering 
pipelines. Such facilities in Class 1, Class 2, and Class 3 locations 
would need to be surveyed twice each calendar year (at intervals not 
exceeding 7\1/2\ months), compared with once per year under current 
regulations. This is the same survey interval used for fugitive methane 
emissions monitoring for compressor stations under the existing and 
proposed EPA requirements (for example, 40 CFR 60.5397a(g)(2) for new 
sources). More frequent leakage surveys for such facilities would 
ensure operators detect and repair leaks earlier, reducing total 
emissions and reducing the risk that a leak can degrade into a rupture 
or other incident. Facilities in Class 4 locations would need to be 
surveyed at least 4 times each calendar year (at intervals not 
exceeding 4\1/2\ months) due to the potential for comparatively more 
significant public safety risks in the event of a leak due to their 
proximity to ignition sources and densely occupied buildings.

     Summary of Transmission and Regulated Gathering Leakage Survey
                               Amendments
------------------------------------------------------------------------
            Facility                   Existing            Proposed
------------------------------------------------------------------------
Non-odorized Class 3............  Twice a year not    No change.
                                   to exceed 7\1/2\
                                   months.
Non-odorized Class 4............  Four times a year   No change.
                                   not to exceed 4\1/
                                   2\ months.
All other transmission..........  Once a year not to  No change.
                                   exceed 15 months.
HCA class 1, 2, or 3............  No specific         Twice a year not
                                   standard.           to exceed 7\1/2\
                                                       months.
HCA class 4.....................  No specific         Four times a year
                                   standard.           not to exceed 4\1/
                                                       2\ months.
Valves, flanges, pipeline tie-    No specific         Same as proposed
 ins with valves and flanges,      standard.           HCA frequencies.
 ILI launcher and ILI receiver
 facilities, and leak prone pipe.
Leak detection equipment........  Only required for   Required except
                                   non-odorized        for non-HCA class
                                   class 3 and class   1 and class 2
                                   4.                  with a
                                                       notification.
Regulated gathering.............  Existing            Require proposed
                                   transmission line   leakage survey
                                   requirements        requirements for
                                   apply to            all regulated
                                   offshore, Type A,   gathering lines.
                                   Type B, and
                                   certain Type C
                                   gathering lines.
------------------------------------------------------------------------
Note: The most frequent survey would apply.

    PHMSA also proposes to increase the frequency of patrols on gas 
transmission, offshore gathering, and Types A, B, and C gathering 
pipelines by replacing the current, scaled approach within Sec.  
192.705(b) of between one and four patrols per year based on class 
location and the presence of a highway or railroad crossing with a 
global, baseline requirement for those operators to perform 12 patrols 
along the entirety of their pipelines each calendar year (at intervals 
not exceeding 45 days). Patrols are primarily visual surveys of the 
right of way and may be performed with or without leak detection 
equipment. PHMSA understands those increased frequencies to be 
appropriate because patrols are valuable not only for identifying 
existing leaks and incidents, but also because they are a relatively 
low-cost method for preemptive identification and mitigation of 
potential threats to pipeline integrity. In conducting patrols, 
operators should consider potential threats such as right of way 
incursions (such as construction, excavation, or agricultural 
activities), signs of earth movement or flooding, or the presence of 
new structures potentially indicating a change in class location. In 
addition to the general leak detection and pipeline integrity benefits 
associated with performing right of way patrols described in section 
IV.A.2, requiring patrols provides an opportunity to update class 
location surveys and potential impact circle surveys. PHMSA further 
notes that operators can control their compliance burdens from the 
proposed increased patrols by coupling them with other operations and 
maintenance tasks such as leakage surveys (provided that the operator 
includes both a visual survey of the right-of-way and a leakage survey 
with leak detection equipment) or by leveraging mobile technologies.
    PHMSA expects its proposed amendments to leakage survey and right-
of-way patrol practices would be reasonable, technically feasible, 
cost-effective, and practicable for affected gas transmission and 
gathering pipeline operators. As explained above, operators of affected 
gas transmission and gathering pipelines (some of which operators have 
both gas transmission and gathering pipeline facilities within their 
systems) are already subject to prescriptive periodic leakage surveys 
requirements; affected operators also have the option to sync their 
patrol and leakage survey requirements to minimize compliance burdens 
(provided that the operator includes both a visual survey of the right-
of-way and a leakage survey with leak detection equipment). PHMSA's 
proposed amendments would merely increase prescribed frequencies within 
Federal regulation as a function of factors (including location in HCAs 
and occupied buildings; components/equipment with complex 
configurations; material composition; operating and maintenance 
history) probative of leak susceptibility--and by extension, risks to 
public safety and the environment. PHMSA further notes that, insofar as 
those factors the NPRM employs as bases for increased leak detection 
and patrol frequency are widely understood to be potential threats to 
the integrity of pipelines, they are among the phenomena that 
reasonably prudent operators would evaluate, and potentially adopt 
mitigation measures to address, in ordinary course to protect public 
safety and the environment from releases of pressurized (natural, 
flammable, toxic, or corrosive) gases from their pipelines and minimize 
loss of commercially valuable commodities. Additionally, operators 
would have flexibility (as appropriate for their needs and their 
pipelines' operational characteristics

[[Page 31931]]

and environment) in choosing between commercially available, advanced 
leakage detection equipment satisfying the performance standards 
proposed in this NPRM for use in those leakage surveys. Viewed against 
those considerations and the compliance costs estimated in the 
Preliminary RIA, PHMSA expects its proposed amendments will be a cost-
effective approach to achieving the commercial, public safety, and 
environmental benefits discussed in this NPRM and its supporting 
documents. Lastly, the proposed compliance timelines--based on an 
effective date of the proposed requirements six months after the 
publication date of a final rule in this proceeding (which would 
necessarily be in addition to the time since issuance of this NPRM)--
would provide operators ample time to implement requisite changes in 
their leakage survey practices and manage any related compliance costs.
3. Leakage Surveys and Patrols for Types B and C Gas Gathering 
Pipelines--Sec. Sec.  192.9, 192.705, and 192.706
    PHMSA proposes to apply to Types B and C gas gathering pipelines 
the leakage survey and patrol requirements proposed in this NPRM for 
gas transmission, offshore gathering, and Type A gathering pipelines.
    PHMSA has long recognized the public safety risks associated with 
gathering pipelines and has general authority under 49 U.S.C. 60102 to 
issue minimum Federal pipeline safety standards necessary to ``meet the 
need for gas pipeline safety [. . .] and protect [] the environment.'' 
For that reason, PHMSA has in the past extended select part 192 
requirements--including leak survey requirements at Sec.  192.706--
applicable to gas transmission pipelines to a minority (only the 
largest, or closest to occupied buildings) of the Type C gas gathering 
pipelines posing the greatest risks to public safety. Existing Sec.  
192.9 does not require operators of Type B and Type C gathering 
pipelines to conduct patrols pursuant to Sec.  192.705.
    However, the historical, limited approach in applying Sec. Sec.  
192.705 (patrol) and 192.706 (leakage survey) requirements to Types B 
and C gathering lines is inadequately protective of public safety and 
the environment. Recent aerial methane emissions surveys discussed in 
section II.C above yield that leaks from gas gathering line pipe, the 
vast majority of which are Type C or Type R pipelines located in Class 
1 locations, in particular are a significant contributor to methane 
emissions. Further, the GHGI data discussed in section II.E reveals 
that fugitive methane emissions from all types of gas gathering line 
pipe vastly exceed emissions from gas transmission line pipe both in 
total and on a per-mile basis. Leaks from gathering line pipe can 
therefore be correspondingly greater contributors to the climate crisis 
than leaks from gas transmission line pipe. Further, because natural 
gas gathering pipelines carry unprocessed natural gas, any leak from 
those pipelines would release VOCs and HAPs such as benzene to the 
environment and risk accelerated degradation of pipeline integrity from 
corrosives entrained in the natural gas. PHMSA understands that leaks 
from gathering lines transporting other gases that are flammable, 
toxic, or corrosive could entail significant public safety and 
environmental consequences as well. Because of these significant risks 
to public safety and the environment posed by Types B and C gathering 
lines, PHMSA has proposed that all Type C gathering lines be subject to 
the same Sec.  192.706 requirements governing leakage survey equipment 
and frequency as gas transmission and Types A and B gathering 
pipelines. Similarly, PHMSA proposes to require patrol frequencies for 
Type B and Type C gathering lines identical to the patrol requirements 
for as transmission and Type A gathering pipelines. PHMSA understands 
that its proposed extension of these mutually-reinforcing, enhanced 
patrol and leakage survey requirements would ensure timely prevention, 
discovery and remediation of leaks on Types B and C gas gathering 
lines. PHMSA invites comments concerning the value of requiring more or 
less frequent leakage surveys of transmission and gathering pipelines 
(for potential inclusion within a final rule in this proceeding). 
Comments on these questions are especially helpful to PHMSA when they 
are supported by research or operational experience, along with the 
potential safety and environmental benefits and potential costs of a 
particular approach (including whether that approach would be 
technically feasible, cost-effective, and practicable).
    PHMSA expects its proposed amendments to extend leakage survey and 
right-of-way patrol practices to all Types B and C gas gathering 
pipeline operators would be reasonable, technically feasible, cost-
effective, and practicable. Patrols and leakage surveys using leak 
detection equipment are widely-employed tools adopted by reasonably 
prudent operators in ordinary course for identifying and mitigating 
leaks on, or threats to the integrity of, pipelines transporting 
commercially valuable pressurized (natural, corrosive, toxic, or 
flammable) gases. Precisely for that reason, PHMSA expects that some 
Types B and C gas gathering pipeline operators affected by this NPRM's 
proposed requirements for leakage survey and right-of-way patrols may 
already voluntarily undertake leakage surveys and patrols on their 
facilities. Those and other operators of Types B and C gas gathering 
pipelines (some of which operators may also operate either gas 
transmission or Type A gathering pipelines) may also have pipelines 
within their systems subject to prescriptive periodic leakage survey 
and patrol requirements under Federal or State law. PHMSA's proposed 
amendments would, therefore, better align leakage survey and right-of-
way patrol practices and requirements for Types B and C gas gathering 
lines with requirements for other 192-regulated gas pipelines. 
Additionally, PHMSA's proposed periodicities for such surveys and 
patrols would also turn on factors (including location in HCAs and 
occupied buildings; components/equipment; material composition; 
operating and maintenance history) well-understood to be probative of 
leak susceptibility--and by extension, risks to public safety and the 
environment. Affected operators would also have the option to sync 
their patrol and leakage survey requirements to minimize compliance 
burdens (provided that the operator includes both a visual survey of 
the right-of-way and a leakage survey with leak detection equipment). 
And operators would have flexibility (as appropriate for their needs 
and their pipelines' operational characteristics and environment) in 
choosing between commercially available, advanced leakage detection 
equipment satisfying the performance standards proposed in this NPRM 
for use in their leakage surveys. Viewed against those considerations 
and the compliance costs estimated in the Preliminary RIA, PHMSA 
expects its proposed amendments will be a cost-effective approach to 
achieving the commercial, public safety, and environmental benefits 
discussed in this NPRM and its supporting documents. Lastly, the 
proposed compliance timelines--based on an effective date of the 
proposed requirements six months after the publication date of a final 
rule in this proceeding (which would necessarily be in addition to the 
time since issuance of this NPRM)--would provide operators ample time 
to implement requisite leakage survey and patrol practices and manage 
any related compliance costs.

[[Page 31932]]

    PHMSA solicits comment on whether it would be appropriate to apply 
any of the requirements proposed herein to Type R gathering pipelines 
not currently regulated under part 192. Comments on this question are 
especially helpful if they address the potential safety and 
environmental benefits and potential costs of that particular approach, 
including whether that approach would be technically feasible, cost-
effective, and practicable.
4. Liquefied Natural Gas Facilities--Sec.  193.2624
    Part 193 does not currently require that operators perform periodic 
surveys of LNG facility components and equipment for methane leakage to 
the atmosphere. However, as described in section II.C.2, equipment 
leaks and other fugitive methane emissions are the second largest 
methane emissions source from LNG storage facilities and the largest 
methane emissions source from LNG export terminals.
    PHMSA therefore proposes a new Sec.  193.2624 to require a 
quarterly methane leakage survey using leak detection equipment and 
remediation of any methane leaks discovered in accordance with the 
operator's maintenance or abnormal operations procedures. Leaks 
discovered would need to be remediated on a schedule established within 
those procedures. Methane leakage surveys would only need to be 
conducted on components and equipment containing methane or LNG in 
normal operations. PHMSA further proposes a minimum equipment 
sensitivity requirement of 5 ppm--along with validation and calibration 
requirements--consistent with the proposed requirements governing the 
performance of leak detection equipment described in section IV.B below 
for part 192-regulated gas pipeline facilities. PHMSA expects that 
these proposed enhanced methane leakage and repair requirements would 
improve public safety by allowing for timely identification and 
remediation of potential ignition sources within part 193-regulated LNG 
facilities, as well as reduce a key source of fugitive GHG emissions 
from those facilities. Additionally, eliminating product losses results 
in cost savings that improve the competitiveness of LNG storage and 
export facilities, further increasing the net benefits of this 
proposal. PHMSA also proposes that, consistent with its proposed 
revisions to part 191 leak detection and repair reporting requirements 
for part 192-regulated gas pipeline facilities, PHMSA would propose 
conforming revisions to its annual report form for part 193-regulated 
facilities \230\ to ensure meaningful reporting of all methane leaks 
detected or repaired by operators pursuant to Sec.  193.2624.
---------------------------------------------------------------------------

    \230\ PHMSA, Form 7300.1-3, ``Annual Report Form for Liquefied 
Natural Gas Facilities (Oct. 2014). The instructions for Form 
7300.1-3 states that ``a non-hazardous release that can be 
eliminated by lubrication, adjustment, or tightening is not a 
leak.'' PHMSA, Instructions for Form 7300.1-3 at 4 (Oct. 2014). That 
historical understanding is inconsistent with PHMSA's understanding 
of the PIPES Act of 2020 premise that all leaks of methane are 
hazardous to the environment because they contribute to climate 
change. PHMSA is not, however, proposing in this NPRM to modify the 
historical reporting exception with respect to releases of other, 
non-methane, hazardous materials within an LNG facility.
---------------------------------------------------------------------------

    PHMSA expects its proposed leakage survey practices would be 
reasonable, technically feasible, cost-effective, and practicable for 
affected LNG facility operators. PHMSA notes that some LNG facility 
operators may operate transmission pipelines supplying natural gas to 
their facilities; those operators could use their existing leakage 
survey practices as a foundation for development of leakage survey 
requirements tailored to their LNG facilities. PHMSA further notes 
that, insofar as leakage surveys using leak detection equipment are 
widely understood to be essential tools in identifying and mitigating 
threats to the integrity of pipelines transporting methane within any 
gas pipelines, they are among the practices that reasonably prudent 
operators would adopt in ordinary course to protect public safety and 
the environment from releases of methane from equipment and components 
in LNG facilities and minimize loss of a commercially valuable 
commodity. Additionally, operators would have flexibility in choosing 
between leakage detection equipment satisfying the performance standard 
proposed in this NPRM for use in those leakage surveys. Viewed against 
those considerations and the compliance costs estimated in the 
Preliminary RIA, PHMSA expects its proposed amendments will be a cost-
effective approach to achieving the commercial, public safety, and 
environmental benefits discussed in this NPRM and its supporting 
documents. Lastly, the proposed compliance timelines--based on an 
effective date of the proposed requirements six months after the 
publication date of a final rule in this proceeding (which would 
necessarily be in addition to the time since issuance of this NPRM)--
would provide operators ample time to implement requisite changes in 
their leakage survey practices and manage any related compliance costs.
    In order to avoid conflicting with existing regulatory requirements 
and best practices in the National Fire Protection Association 
standard, ``Standard for the Production, Storage, and Handling of 
Liquefied Natural Gas (LNG)'' governing the requirements for LNG 
facilities (NFPA 59A) and other standard practices, PHMSA has not 
proposed in this NPRM for LNG facilities a comprehensive, advanced leak 
detection and repair program framework along the lines of that 
discussed below in section IV.B for part 192-regulated gas pipeline 
facilities. For example, section 9.3 of the 2001 edition of NFPA 
59A,\231\ which is incorporated by reference within PHMSA regulations 
at Sec.  193.2801, requires continuous gas monitoring in the vicinity 
of LNG process equipment, and section 12.4.2 requires an alarm at 25% 
LEL or less. Additionally, certain equipment in LNG plants that are not 
part of distribution systems may be subject to EPA leak detection and 
repair requirements in 40 CFR part 60 depending on the purpose and 
contents of the equipment. However, facilities storing or carrying 
natural gas or LNG are typically subject to the standards for gas 
production and transmission systems in 40 CFR part 60. The subpart OOOO 
and OOOOa standards are described in greater detail in section IV.C.3 
and include semiannual fugitive emissions monitoring surveys and repair 
of all leaks visible with an OGI device or that produce an instrument 
reading of 500 ppm or greater.\232\ For a subpart OOOOa facility, the 
operator must attempt repair no later than 30 days after detecting the 
fugitive emissions and must complete the repair within 30 days of the 
first attempt or during the next scheduled shutdown.\233\ Finally, 
detecting leaks on equipment such as at LNG plants is generally less 
challenging than doing so on buried pipelines. PHMSA is pursuing a 
parallel rulemaking (under RIN 2137-AF45) in which it could consider 
leak monitoring, surveying, and patrolling requirements more 
holistically.
---------------------------------------------------------------------------

    \231\ NFPA, NFPA-59A: Standard for the Production, Storage, and 
Handling of Liquefied Natural Gas (LNG)--2001 Edition (2001).
    \232\ 40 CFR 60.5397a(a)(1) and (h).
    \233\ 40 CFR 60.5397(h).
---------------------------------------------------------------------------

B. Advanced Leak Detection Programs--Sec.  192.763

    Section 113 of the PIPES Act of 2020 requires PHMSA to issue 
performance standards for operator leak detection and repair programs 
reflecting the capabilities of commercially available, advanced leak 
detection technologies

[[Page 31933]]

and practices. To satisfy this mandate, PHMSA proposes to introduce a 
new Sec.  192.763 to require operators establish written Advanced Leak 
Detection Programs (ALDPs) and to establish performance standards for 
both the sensitivity of leak detection equipment and for the 
effectiveness of those ALDPs. This new requirement would provide 
benefits to both public safety and the environment by ensuring that 
pipeline operators have programs in place to promptly detect and repair 
leaks of all gas pipelines subject to part 192, thereby reducing harm 
to public safety and the environment.
    An ALDP represents a complementary set of mutually reinforcing 
technologies and procedures (including analytics) that the operator 
uses to detect all leaks. PHMSA proposes to require that an operator's 
written ALDP include four main elements: leak detection equipment 
employing commercially available advanced technology, leak detection 
procedures, prescribed leakage survey frequencies, and program 
evaluation. Note that grading and repairing leaks after investigation 
is governed by the proposed Sec.  192.760 described in section IV.C of 
this NPRM. The proposed requirements in this section would apply to 
operators of all gas distribution lines, gas transmission lines, 
offshore gathering, and Types A, B, and C regulated onshore gathering 
pipelines.
    PHMSA expects each of the proposed ALDP requirements discussed 
below would be reasonable, technically feasible, cost-effective, and 
practicable for all affected gas pipeline operators. PHMSA understands 
that most operators of gas pipelines that would be subject to those 
requirements may already employ one or more of its proposed ALDP 
elements voluntarily because (inter alia) a reasonably prudent operator 
would in ordinary course employ a systematic, defense-in-depth approach 
to identifying leaks given the commercial value of, and potential risks 
to public safety and the environment posed by, the commodities 
transported (natural gas or flammable, toxic, or corrosive pressurized 
gases). Alternatively, an operator may employ one of more of PHMSA's 
proposed ALDP elements as a compliance strategy for existing PHMSA or 
State leak detection or integrity management requirements. Regardless, 
PHMSA's proposals build and on those existing practice by creating a 
common, straightforward regulatory framework for addressing leak 
detection across all part 192-regulated gas pipelines. Within that 
common framework, moreover, operators would retain significant 
flexibility to select (as appropriate for a pipeline's operational 
needs and operating environment) a suite of mutually reinforcing leak 
detection equipment, analytics, and practices, satisfying a baseline 
leak detection performance standard derived from commercially available 
advanced leak detection technology in a way that minimizes their 
compliance costs. PHMSA's proposal even contemplates that some 
operators of gas pipelines may employ (subject to PHMSA review) an 
alternative performance standard as a function of location or gas 
commodity being transported. Viewed against those considerations and 
the compliance costs estimated in the Preliminary RIA, PHMSA expects 
its proposed amendments will be a cost-effective approach to achieving 
the commercial, public safety, and environmental benefits discussed in 
this NPRM and its supporting documents. Lastly, the proposed compliance 
timelines--based on an effective date of the proposed requirements six 
months after the publication date of a final rule in this proceeding 
(which would necessarily be in addition to the time since issuance of 
this NPRM)--would provide operators ample time to implement requisite 
protocols, obtain leak detection equipment, and manage any related 
compliance costs.
1. Leak Detection Technology Standards--Sec.  192.763(a)(1)
    The first element in an ALDP is the leak detection technology that 
the operator would use to perform leakage surveys, investigate leaks, 
and pinpoint leak locations. These technology requirements are proposed 
in Sec.  192.763(a)(1). Each operator's ALDP would include a list of 
leak detection equipment that the operator uses for leakage surveys, 
leak investigations, and pinpointing leaks. Consistent with the mandate 
in section 113 of the PIPES Act of 2020, PHMSA proposes to specify when 
leak detection equipment would be required and when an operator may 
rely on methods that rely on human or animal senses. Specifically, the 
NPRM proposes to amend Sec.  192.723 to require that all leakage 
surveys on gas distribution pipelines be performed with leak detection 
equipment in light of the high risk to public safety from distribution 
pipelines, which are often located in the vicinity of population 
centers. Additionally, as described in section IV.A.2 of this NPRM, all 
leakage surveys on onshore gas transmission and gathering pipelines 
performed under Sec.  192.706 would require the use of leak detection 
equipment, except when the operator of a gas transmission or gathering 
pipeline in a Class 1 or Class 2 location determines that a survey 
using human senses would be sufficient, subject to review by PHMSA, as 
provided in Sec.  192.706(a)(1). This default requirement that ALDPs of 
onshore regulated gas gathering, transmission, and distribution 
operators use leak detection equipment in leakage surveys would enhance 
operators' ability to identify and repair leaks on pipelines in a 
timely manner, and therefore minimize releases and prevent leaks from 
degrading. It would also serve to improve leak detection data to 
improve the predictive power of leak management programs, integrity 
management programs, and artificial intelligence services that can 
identify systemic pipeline design or repair issues.
    PHMSA further proposes that any leak detection equipment used must 
have a minimum sensitivity of 5 ppm or less. A reading of 1% of the 
lower-explosive limit of methane gas at atmosphere is approximately 500 
ppm; a minimum sensitivity of 5 ppm would therefore provide a 
protective threshold of detection sensitivity. That threshold is also 
consistent with the performance of commercially available leak 
detection equipment. Table 2 of the Appendix G-192-11 of the GPTC Guide 
provides examples of commercially available methane detection 
technologies and the sensitivity and detection ranges for those 
technologies. That information is reproduced in the table below. In 
addition to the devices listed below, OGI cameras, devices that are 
capable of visualizing methane gas leaks and other fugitive emissions, 
are commonly used for fugitive emissions monitoring at LNG plants, 
compressor stations, and other facilities.

           Methane Leak Detection Technologies and Performance
------------------------------------------------------------------------
           Technology                 Sensitivity            Range
------------------------------------------------------------------------
Semiconductor...................  1-100 ppm.........  0-100 ppm.
Flame Ionization................  1 ppm.............  0-10,000 ppm.

[[Page 31934]]

 
Open Path Infrared (IR) Tunable   5 ppm-meter.......  0-100,000 ppm-
 diode laser absorption                                meter.
 spectroscopy.
Closed Path Bifringent IR.......  1 ppm.............  0-2,500 ppm.
Closed Path IR Laser............  0.03-100 ppm......  0-1000 ppm.
------------------------------------------------------------------------

    Although each of the technologies listed above has advantages and 
limitations that may make it more or less appropriate for leakage 
surveys on particular gas pipelines or operating conditions, PHMSA's 
proposed 5 ppm performance standard balances each of the following: a 
methane sensitivity threshold consistent with the performance of state-
of-the-art, commercially-available technologies; robust margin to risk 
of ignition; and flexibility for operators to choose from a baseline of 
high-quality equipment for their unique needs. For example, PHMSA 
understands that modern FID units and closed-path IR and laser-based 
systems are capable of sub-ppm and parts-per-billion detection. 
However, quality semiconductor sensors and open-path IR devices have 
important applications despite comparatively lower-sensitivity. 
Semiconductor sensors are typically much smaller than other detection 
devices and therefore are useful in confined spaces and other 
situations where a smaller tool is necessary to access the space. 
Additionally, semiconductor sensors are often designed to incorporate 
intrinsically safe features, which minimizes the risk of ignition in 
situations where a flammable atmosphere may be present. Similarly, some 
handheld open-path IR systems can have a sensitivity of 5 ppm-meter at 
its maximum effective range \234\ but have the advantage of allowing a 
surveyor to detect methane plumes from a distance. This allows operator 
leakage surveyors to safely and efficiently survey facilities that may 
otherwise be difficult or unsafe to access. However, the proposed leak 
detection performance standard would generally exclude each of odorant 
``sniffers'' used to test the adequacy of odorization, less-sensitive 
combustible gas indicators, and most gas monitors intended for confined 
space gas monitoring rather than methane leak detection--even as PHMSA 
acknowledges such devices may nevertheless be useful in connection with 
leak grading (pursuant to proposed Sec.  192.760), as tools 
supplementing ALDP-compliant leak detection equipment, or as authorized 
pursuant to proposed Sec.  192.763(c).
---------------------------------------------------------------------------

    \234\ PPM-meter is a ``path integrated'' summation of measured 
gas concentration used for open-path devices that sums gas 
concentration per meter measured up to the effective range in front 
of the device. Sensitivity may be higher at closer ranges depending 
on the specific technology used.
---------------------------------------------------------------------------

    As discussed throughout this section, other ALDP programmatic 
requirements backstop any limitations on the ability of particular leak 
detection technologies to contribute to the program-wide performance 
standard at Sec.  192.763(b) that an ALDP detects all leaks of 5 ppm or 
more when measured 5 feet from the pipeline. For example, PHMSA 
acknowledges that an operator may determine, based on its operational 
needs or the operating environment of a particular pipeline, that leak 
detection equipment more sensitive than 5 ppm is necessary to meet the 
ALDP programmatic performance standard at Sec.  192.763(b). For 
example, an operator may determine that an efficient means of meeting 
the ALDP performance standard at Sec.  192.763(b) would be to perform 
leakage surveys by first using very sensitive (in the sub-ppm or low 
ppb range) vehicle or aircraft mounted sensors, followed thereafter by 
spot-checks using handheld devices with the minimum sensitivity of 5 
ppm proposed at Sec.  192.763(a)(1)(ii). Similarly, an operator may 
supplement any leak detection equipment meeting the minimum sensitivity 
requirements proposed at Sec.  192.763(a)(1)(ii) with other techniques 
for pinpointing leak location (e.g., soap bubble testing) or 
technologies (e.g., devices for measuring release rate for 
differentiating between leak grades) for grading identified leaks 
pursuant to PHMSA's proposed Sec.  192.760.
    PHMSA further notes that operators would be able to, pursuant to 
the proposed Sec.  192.763(c), seek PHMSA review of use of an 
alternative ALDP performance standard that may entail the use of 
alternative (including less sensitive) leak detection technology than 
that proposed under Sec.  192.763(a)(1). This process is available for 
each of natural gas pipelines (other than distribution pipelines) in 
Class 1 and 2 locations, and any part 192-regulated pipeline facility 
transporting flammable, toxic, or corrosive gas other than natural 
gas.\235\ PHMSA acknowledges the fast-evolving state-of-the-art in leak 
detection technologies for methane and other gases and seeks comments 
on whether and in what manner it could integrate within a final rule 
requirements for technologies that may not have specified 
sensitivities, including continuous pressure wave monitoring, fiber 
optic sensing, OGI, and LIDAR based detection technologies, along with 
the potential safety and environmental benefits and potential costs of 
a particular approach (including whether that approach would be 
technically feasible, cost-effective, and practicable). PHMSA expects 
that it would consider the use of such technologies under the Sec.  
192.763(c) process or as supplement to other equipment satisfying the 
minimum sensitivity performance requirements proposed herein.
---------------------------------------------------------------------------

    \235\ Although PHMSA's proposed 5 ppm default performance 
standard for all part 192-regulated gas pipelines is based 
principally on commercially available, advanced methane leak 
detection technology for use with natural gas pipelines, PHMSA 
understands that commercially available, advanced leak detection 
technology for use with other part 192-regulated gas pipeline 
facilities may (when considered either separately or within a suite 
of mutually-reinforcing technologies) offer comparable leak 
detection ability. Further, as explained in the paragraph above, the 
NPRM contemplates operators of gas pipeline facilities transporting 
gases other than natural gas (e.g., hydrogen) may request the use of 
an alternative leak detection performance standard and supporting 
leak detection equipment.
---------------------------------------------------------------------------

    Apart from minimum sensitivity requirements described above, PHMSA 
does not propose to require the use of any particular leak detection 
equipment or technology for every operator or for each type of 
pipeline. While the PIPES Act of 2020 directs PHMSA to require the use 
of advanced leak detection technologies and practices, Congress defined 
this requirement in terms of a performance standard for leak detection 
and repair programs and described several possible approaches in the 
statute. PHMSA therefore does not propose to narrowly define advanced 
leak detection in terms of a particular technology, process, 
manufacturer, or equipment. One type of technology may not always be 
appropriate for every flammable, corrosive, or toxic gas, each type of 
pipeline facility or even across

[[Page 31935]]

the range of operational/environmental conditions (e.g., seasonal 
temperature, humidity, or precipitation patterns) within which a 
particular pipeline operates. Rather than a technology standard, PHMSA 
expects each of the periodic evaluation and improvement element of each 
ALDP (proposed in Sec.  192.763(a)(4)), and the ALDP performance 
requirement (proposed in Sec.  192.763(b), described later in this 
section), would encourage operators to continually evaluate and 
incorporate within their ALDPs such newly commercialized technologies 
as appropriate for their systems over time. This flexible approach 
would ensure that operators' leakage detection equipment keeps pace 
with the state-of-the-art in leak detection technology. Additionally, 
this NPRM proposes to require operators to select their leak detection 
equipment based on a documented analysis that considers, at a minimum, 
the gas being transported, the size, configuration, operating 
parameters, and operating environment of the operator's system. An 
operator would be required to choose leak detection technologies that 
are best able to detect, investigate, and locate all leaks considering 
these factors. For example, an advanced mobile leak detection system 
could be an effective tool for detecting methane leaks in a suburban 
distribution system but may not be optimal for surveying service lines 
in an area with long setbacks or a transmission pipeline with poor road 
access. PHMSA also proposes to require operators to analyze, at a 
minimum, the appropriateness of the following examples of possible 
advanced leak detection technologies and methods, some of which were 
referenced in the PIPES Act of 2020: leakage surveys with optical, 
infrared, or laser-based hand-held devices; continuous monitoring via 
stationary gas sensors, pressure monitoring, or other means; mobile 
surveys from vehicle, satellite, or aerial platforms; and systemic use 
of other technologies capable of detecting and locating leaks 
consistent with the proposed ALDP performance standard at Sec.  
192.763. Operators would be required to maintain records of this 
analysis for five years. Stationary gas detection systems are already 
required on compressor stations under PHMSA's existing regulations at 
Sec.  192.736. Likewise, section 16.4 of the 2001 edition of NFPA 
59A,\236\ which is incorporated by reference into the federal safety 
standards for LNG facilities in part 193, requires monitoring of 
enclosed buildings and other areas that can have the presence of LNG or 
other hazardous fluid (including natural gas), and specifies flammable 
gas alarm settings in section 16.4.2. PHMSA invites comments on the 
value of introducing requirements for continuous monitoring systems, 
via stationary gas detection systems, pressure monitoring, or other 
means (including requirements for the use of specific methods or 
technologies), on other types of pipeline facilities (including whether 
continuous monitoring would be most appropriate at any particular 
facilities or locations, or in other particular conditions) within a 
final rule in this rulemaking proceeding.\237\ Comments are especially 
helpful to PHMSA when they are supported by research or operational 
experience, along with the potential safety and environmental benefits 
and potential costs of a particular approach (including whether that 
approach would be technically feasible, cost-effective, and 
practicable).
---------------------------------------------------------------------------

    \236\ NFPA, NFPA-59A: Standard for the Production, Storage, and 
Handling of Liquefied Natural Gas (LNG)--2001 Edition (2001).
    \237\ To the extent that a comment proposes to require 
installation of such technologies on a pipeline, PHMSA also solicits 
comment on the potential application of PHMSA's statutory 
prohibition on retroactive design and installation standards. See 49 
U.S.C. 60104(b).
---------------------------------------------------------------------------

2. Leak Detection Practices--Sec.  192.763(a)(2)
    The second program element in proposed Sec.  192.763(a)(2) consists 
of the operator's procedures related to leak detection, investigation, 
and location. Generally, this would involve supplementing or revising 
existing procedures in the operator's manual of procedures. At a 
minimum, the ALDP would include procedures for performing leakage 
surveys as well as subsequent investigation and location of identified 
leaks; operator procedures would provide instruction on whether and how 
each type of leak detection equipment included in the ALDP would be 
used in performing those tasks. To ensure that operators use procedures 
appropriate for environmental conditions such as temperature, wind, 
time of day, precipitation and humidity, the operator must define under 
which conditions the procedure may and may not be used. Additionally, 
the procedures must be consistent with any instructions and allowable 
operating and environmental parameters issued by the leak detection 
equipment manufacturer to ensure equipment effectiveness. For example, 
some devices or systems may be unsuitable for use in certain weather or 
atmospheric conditions, or at certain times of day, or in certain 
temperatures. As noted in the discussion of leak detection practices in 
section II.F, establishing and following procedures with parameters 
appropriate for the leak detection technologies and practices is 
critical for reliably detecting leaks, especially in challenging 
conditions. This requirement also addresses the findings from the 
NTSB's investigation of a 2018 gas explosion involving failed leakage 
surveys (discussed in section II.H of this NPRM.) due to the operator's 
improper use of leak detection equipment.\238\
---------------------------------------------------------------------------

    \238\ National Transportation Safety Board. ``Pipeline Accident 
Report: Atmos Energy Corporation Natural Gas-Fueled Explosion: 
Dallas, Texas: February 23, 2018.'' NTSB/PAR-21/01. Jan. 12, 2021. 
Washington, DC https://www.ntsb.gov/investigations/AccidentReports/Reports/PAR2101.pdf.
---------------------------------------------------------------------------

    PHMSA proposes to require that an operator's ALDP procedures 
include investigating and pinpointing the location of all leak 
indications. For onshore pipelines and offshore pipeline facilities 
above the waterline, PHMSA proposes in Sec.  192.763(a)(2) to require 
that pinpointing location be performed using handheld leak detection 
equipment with a minimum sensitivity of 5 ppm. This proposed 
requirement would complement PHMSA's proposed ALDP programmatic 
performance standard in Sec.  192.763(b). If leak location is 
pinpointed with handheld leak detection equipment during an initial 
leakage survey, the initial survey would satisfy this requirement. 
PHMSA proposes that pinpointing leak location on submerged offshore 
pipelines (including riser piping up to the waterline) would not 
require the use of leak detection equipment because submerged pipeline 
leaks are visibly conspicuous.
    To ensure the effectiveness of leak detection equipment, PHMSA 
proposes to require at Sec.  192.763(a)(2)(iii) that an operator have 
procedures for validating that a leak detection device meets the 5-ppm 
minimum sensitivity requirement in Sec.  192.763(a)(1)(ii)prior to 
initial use. This would consist of testing the equipment measurements 
against a known concentration of gas. Operators would have to maintain 
records that their leak detection equipment has been validated for five 
years after the date each device ceases to be used in the operator's 
ALDP. This is a one-time validation separate from the periodic 
calibration required under proposed Sec.  192.763(a)(2)(iv) described 
below. PHMSA also proposes to require that operators have procedures 
for the maintenance and calibration of leak detection equipment--
including at least

[[Page 31936]]

any maintenance and calibration procedures recommended by the equipment 
manufacturer--to ensure that equipment is functioning as intended 
throughout its service life. Finally, PHMSA proposes to require that 
operators recalibrate leak detection equipment following an indication 
of malfunction.
3. Leakage Survey Frequency--Sec.  192.763(a)(3)
    The third element that PHMSA proposes to require of an ALDP is the 
frequency of leakage surveys, which is specified in proposed Sec.  
192.763(a)(3). Minimum leakage survey frequencies are defined in Sec.  
192.723 for gas distribution pipelines and in Sec.  192.706 for gas 
transmission, offshore gathering, and Types A, B, and C gathering 
pipelines. As noted in section IV.A, less sensitive survey equipment 
may require more frequent surveys in order to provide an equivalent 
degree of leak or emissions detection.\239\ If more frequent leakage 
surveys are necessary to reliably meet the ALDP programmatic 
performance standard in proposed Sec.  192.763(b), or as otherwise 
specified by the operator, that must be noted in the operator's ALDP. 
For example, more frequent leakage surveys may be appropriate for less 
sensitive leak detection equipment authorized for use pursuant to 
proposed Sec.  192.763(c), challenging survey conditions, or facilities 
known to leak based on their material, design, or past operating and 
maintenance history. As noted above in section IV.B.1, PHMSA invites 
comments on the value of requiring continuous monitoring systems on 
these types of facilities or any other pipeline facilities (for 
potential inclusion within a final rule in this proceeding). Comments 
are especially helpful to PHMSA when they are supported by research or 
operational experience, along with the potential safety and 
environmental benefits and potential costs of a particular approach 
(including whether that approach would be technically feasible, cost-
effective, and practicable).
---------------------------------------------------------------------------

    \239\ Ravikumar, Arvind Ph.D. ``FEAST-Based Evaluation of 
Methane Leak Detection and Repair Programs Using New Technologies.'' 
EPA Methane Detection Technology Workshop (August 24, 2021). https://www.epa.gov/controlling-air-pollution-oil-and-natural-gas-industry/epa-methane-detection-technology-workshop. Day 2 at 1:33:50.
---------------------------------------------------------------------------

4. Program Evaluation and Improvement--Sec.  192.763(a)(4)
    The fourth and final element of an ALDP in Sec.  192.763(a)(4) is 
program evaluation and improvement. At least annually, operators would 
have to re-evaluate the elements of their ALDPs considering, at a 
minimum, the performance of the leak detection equipment used, the 
adequacy of their leakage survey procedures, advances in leak detection 
technologies and practices, the number of leaks initially detected by 
third parties, the number of leaks and incidents on the pipeline, and 
estimated emissions from detected leaks. This proposal is similar in 
principle to the existing continuous improvement requirements under IM 
requirements in part 192, subparts O and P, as well as requirements for 
certain operators to periodically review procedures under Sec.  
192.605(b)(8) and (c)(4). PHMSA expects this proposal would ensure 
operators periodically evaluate ways to improve their leak detection 
programs based on leak detection performance data and advances in 
technology. For example, if an operator finds evidence that their ALDP 
fails to detect leaks during leakage surveys, or that it is finding 
grade 1 or 2 leaks but does not find any grade 3 leaks, changes to 
program elements may be necessary to ensure that the minimum 
performance standard in Sec.  192.763(b) described below is met. This 
provision would offer potential environmental benefits and could also 
result in cost-savings to operators and shippers, by helping further 
reduce product losses from pipeline facilities.
5. Advanced Leak Detection Performance Standard--Sec.  192.763(b)
    The ultimate benchmark for the effectiveness of an operator's ALDP 
would be a holistic, program-wide performance standard at Sec.  
192.763(b). Specifically, PHMSA proposes to require that an ALDP must 
be capable of detecting all leaks that produce a reading of 5 ppm or 
greater of gas when measured from a distance of 5 feet from the 
pipeline, or within a wall-to-wall paved area. As described in the 
discussion of leak detection equipment above, the proposed 5 PPM 
standard represents a protective, detection threshold achievable using 
mainstream, commercially available, advanced leak detection equipment. 
The Sec.  192.763(b) ALDP performance standard is consistent with that 
minimum sensitivity for leak detection equipment, but it focuses on the 
characteristics of the leak (in particular, whether the leak rate or 
operating environment results in a reading of 5 ppm) rather than on the 
sensitivity of the leak detection equipment employed by an operator. 
For example, a walking survey conducted alongside a pipeline with 
thorough, careful, procedures to ensure detection of all leaks could 
achieve this standard with an FID or other handheld device with the 5 
ppm sensitivity required by Sec.  192.763(a). But mobile leak detection 
systems and aerial systems that use gas samplers or other sensors to 
detect leaks at a greater distance may allow for more efficient leakage 
surveying, but could require more sensitive (sensors in the ppb range) 
leak detection equipment coupled with advanced analytics (followed by 
the use of handheld leak detection equipment to pinpoint leak location) 
to detect and locate the same leak. Similarly, leakage surveys 
employing human or animal senses would have to employ leak detection 
equipment to investigate and pinpoint the location of any leaks 
detected during those non-instrumented surveys.
    Some stakeholders attending the 2021 Public Meeting commented that 
leak flow rate would be a more appropriate metric for leak detection 
and ALDP program performance than PHMSA's proposed volumetric 
sensitivity metric.\240\ However, as discussed above in section II.D.4, 
most currently available methane leak detection technologies are 
focused on calculating the concentration of gas in the air rather than 
leak flow rate. Moreover, PHMSA's choice of leak concentration-based 
performance standard for leak detection equipment was informed by the 
goal of (as much as possible) identifying a single performance standard 
that would be well-suited for leak detection on both aboveground and 
buried natural gas pipelines. Additionally, consistent with the GPTC 
Guide grading criteria and as acknowledged in the comments of AGA et 
al. to the 2021 Public Meeting, a concentration-based metric is 
especially useful for addressing explosion risks to public safety 
(regardless of a leak's flow rate). To the extent that operators find 
that leak rate measurements are helpful for identifying or grading 
leaks or in calculating estimated emissions consistent with changes to 
part 191 reporting requirements discussed elsewhere in this NPRM, 
operators may incorporate leak flow rate metrics within their ALDPs to 
supplement leak concentration metrics used in PHMSA's proposed leak 
detection and ALDP performance standard. In particular, leak rate 
measurements may help operators quickly grade certain leaks as grade 2 
leaks based on a leak rate in excess of 10 CFH. Based on available

[[Page 31937]]

information, PHMSA's current assessment is that the proposed Sec.  
192.763(b) ALDP performance standard represents a threshold of 
detection demanding enough to ensure that operator ALDPs are capable of 
detecting nearly all leaks on gas gathering, transmission, and 
distribution pipelines. That said, PHMSA invites comment on whether and 
how an alternative ALDP performance standard--such as a more demanding 
volumetric standard, or a flowrate-based standard--should be adopted in 
the final rule. Proposed alternatives are most helpful when they are 
supported by a discussion of their value for public safety and 
environmental protection, as well as their technical feasibility, cost-
effectiveness, and practicability.
---------------------------------------------------------------------------

    \240\ Written comments submitted before and after the meeting 
are available in the rulemaking docket at Doc. No. PHMSA-2021-0039. 
While some commenters observed that a leak flow rate performance 
standard would be desirable, no commenter provided a suggestion for 
how this could be implemented.
---------------------------------------------------------------------------

6. Alternative Advanced Leak Detection Performance Standard--Sec.  
192.763(c)
    Lastly, because of the comparatively low emissions from natural gas 
transmission pipeline leaks (relative to other gas transmission 
pipeline facilities such as compressor stations),\241\ comparatively 
lower potential safety risks to persons or property in remote areas, 
and the continued development of methane leak detection technologies, 
PHMSA proposes, at Sec.  192.763(c), to allow operators of each of gas 
transmission, offshore gathering, and Types A, B, and C gathering 
pipelines, located in Class 1 or 2 locations and outside of HCAs to 
request an alternative ALDP performance standard (and use of supporting 
leak detection equipment) pursuant to the notification and PHMSA review 
procedures established in Sec.  192.18. PHMSA similarly proposes that 
operators of any species of part 192-regulated gas pipelines 
transporting flammable, toxic, or corrosive gases other than natural 
gas may request use of an alternative ALDP performance standard (and 
use of supporting leak detection equipment).
---------------------------------------------------------------------------

    \241\ See the discussion of GHGI data in section II.E. of this 
NPRM.
---------------------------------------------------------------------------

    The operator must demonstrate, in the notification, that the 
alternative performance standard is consistent with pipeline safety and 
equivalent to the performance standard in Sec.  192.763(b) with respect 
to reducing greenhouse gas emissions and other environmental hazards. 
This flexibility can promote emerging technologies where they may be 
most effective. For example, some aerial survey methods may not yet be 
able to detect small but potentially hazardous, below-ground methane 
leaks from a distribution pipeline system, but they could be an 
efficient leakage survey method for leaks on below-ground onshore gas 
transmission lines, which leaks are larger on average due to the higher 
operating pressure. Similarly, an alternative performance standard may 
be appropriate for flammable, toxic, or corrosive gases for which 
commercially available, advanced leak detection technology either uses 
different units of measure than that provided for in Sec.  192.763(a) 
or is less sensitive than the default 5 ppm performance standard. PHMSA 
proposes to require that notifications submitted under this provision 
must include information about--among other things--the location and 
material properties of the pipeline facility, the gas being 
transported, a description of the proposed alternative performance 
standard, and a description of the ALDP equipment and procedures that 
would be used.

C. Leak Grading and Repair--Sec. Sec.  192.703, 192.760, and 192.769

    As discussed in section II, gas pipeline operator leak grading and 
repair practices are currently insufficient to meet the threats to the 
environment and public safety from leaks on their systems. Current 
requirements lack meaningful requirements for timely grading and repair 
of leaks; only leaks that are ``hazardous'' (a term that is undefined) 
are subject to explicit repair timelines and requirements, and PHMSA's 
IM regulations in subparts O (transmission) and P (distribution) 
largely defer to operator discretion regarding leak repair efforts for 
the small portion of gas pipelines subject to those requirements. Only 
a handful of States have imposed their own, more demanding leak repair 
requirements than PHMSA's. Similarly, while some operators have 
voluntarily adopted their own leak grading and repair practices, many 
operators have no such requirements, and those that do may not apply 
these requirements consistently across different types of pipeline 
facilities.
    PHMSA therefore proposes to address these regulatory gaps by 
establishing requirements at Sec. Sec.  192.703, 192.760, and 192.769 
for all part 192-regulated gas pipeline operators to ensure properly-
trained personnel grade and repair all leaks pursuant to a schedule for 
each grade based on the severity of public safety and environmental 
risks.\242\ PHMSA's proposal includes a leak grading framework informed 
by the criteria of the GPTC Guide--which is familiar to industry and 
State enforcement personnel--to facilitate compliance and regulatory 
oversight. PHMSA's proposed leak grading framework in Sec.  192.760 
would require the classification of every leak on any portion of a gas 
pipeline (including components such as flanges, meters, regulators, and 
ILI launchers and receivers) as either (in order of decreasing 
priority) grade 1, grade 2, or grade 3 based on the magnitude and 
probability of risks posed by that leak to the public and the 
environment, prioritizing remediation of leaks presenting the most 
serious hazards to people or the environment and setting minimum repair 
timelines for each grade. Operators would be obliged to investigate 
each leak discovered on their pipelines immediately and continuously 
until a leak grade determination has been made to ensure that risks to 
public safety and the environment from each leak are diligently 
evaluated and repairs scheduled as appropriate to remedy any risks. The 
NPRM also includes a number of enhancements to the GPTC Guide's three-
tiered framework to address gaps in safety and environmental 
protection, including establishment of repair deadlines for grade 3 
leaks and incentivizing replacement or remediation of pipe known to 
leak. Operator personnel engaged in leakage survey, investigation for 
grading purposes, and repair would be subject to baseline training 
requirements. Lastly, PHMSA has proposed revision of the documentation 
requirements at Sec.  192.605, consistent with statutory language in 
section 114 of the PIPES Act of 2020, to oblige operators of gas 
transmission, distribution, offshore gathering, and Types A, B, and C 
gathering pipelines to update their procedures to provide for the 
replacement or remediation of pipelines known to leak.
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    \242\ These grading requirements apply to all commodities 
transported under part 192, including petroleum gas, as all non-
natural gas commodities covered under part 192 are hazardous to 
human health or the environment. See Sec.  192.3 (definition of 
gas). Petroleum gas systems are subject to some specialized grading 
criteria due to the unique hazards posed by this heavier-than-air 
gas.
---------------------------------------------------------------------------

    PHMSA expects each of the proposed leak grading and repair 
requirements discussed in this section IV.C would be reasonable, 
technically feasible, cost-effective, and practicable for affected gas 
pipeline operators. As explained above, some operators that would be 
subject to this NPRM's proposed requirements have one or more pipelines 
within their systems that are already subject to some leak repair 
(either prescriptive or integrity management-based) requirements under 
PHMSA or State regulatory regimes. Other operators may voluntarily 
exceed minimum regulatory

[[Page 31938]]

requirements given the significant public safety and environmental 
risks posed by releases of pressurized (natural, flammable, toxic, or 
corrosive) gas from their pipelines, or to minimize loss of 
commercially valuable commodity. PHMSA's proposal builds on those 
existing practices by establishing for part 192-regulated gas pipelines 
a common leak repair obligation leveraging the GPTC Guide's familiar 
framework for classifying all leaks--not merely those thought to pose 
imminent risks to public safety. PHMSA in turn calibrated its proposed 
repair timelines for each leak grade based on the magnitude of public 
safety and environmental risks; within those default repair timelines, 
operators may be able to seek extensions or (with respect to compressor 
stations) be relieved of obligations from potential overlapping 
requirements from certain methane emissions requirements imposed by 
other Federal and State regulatory authorities. Viewed against those 
considerations and the compliance costs estimated in the Preliminary 
RIA, PHMSA expects its proposed amendments will be a cost-effective 
approach to achieving the commercial, public safety, and environmental 
benefits discussed in this NPRM and its supporting documents. Lastly, 
the NPRM's proposed compliance timelines--which are based on an 
effective date of six months after the publication date of a final rule 
in this proceeding (which would necessarily be in addition to the time 
since issuance of this NPRM)--would provide operators ample time to 
implement requisite leak grading and repair protocols (including, but 
not limited to, those pertaining to procedure development, post-repair 
inspection, and recordkeeping) and manage any related compliance costs.
1. Leak Repair Requirement--Sec.  192.703(c)
    Consistent with the proposed new leak grading and repair 
requirements at Sec.  192.760(c) discussed below, PHMSA proposes to 
eliminate the current limitation of operators' repair obligation to 
leaks that are ``hazardous'' to public safety. To accomplish this, 
PHMSA proposes to revise Sec.  192.703(c) to require grading and repair 
criteria for all detected leaks. Additionally, PHMSA proposes that its 
expanded leak repair obligations would attach to all part-192 regulated 
gas pipelines because any leak from those pipelines entails risks to 
one or both of public safety and the environment. While any leak of 
methane from a gas pipeline system necessarily entails environmental 
harm proportional to the amount of methane released to the atmosphere, 
PHMSA proposes introducing minimum sensitivity standards for leak 
detection equipment at Sec.  192.763 (discussed below) in recognition 
that some leaks are so small that the harm they present does not 
warrant expending the resources necessary to detect and repair them, 
particularly where the leak is approaching the limits of detection with 
commercially available advanced technologies. This approach is 
consistent with Congress's direction in the PIPES Act of 2020 for PHMSA 
to require that operators repair or replace ``each leaking pipe, except 
a pipe with a leak so small that it poses no potential hazard.'' Under 
the proposed approach, some very small leaks which would escape 
detection would not qualify as a ``leak or hazardous leak'' under Sec.  
192.3, and thus would not be repaired.
2. Replacement of Pipelines Known to Leak--Sec.  192.605
    Among the self-executing mandates within section 114 of the PIPES 
Act of 2020 is a requirement that pipeline operators update their 
procedures to provide for minimizing releases of natural gas; 
eliminating hazardous leaks of natural gas and any other flammable, 
toxic, or corrosive gas; and the replacement or remediation of 
pipelines known to leak based on their material (including cast iron, 
unprotected steel, wrought iron, and historic plastics with known 
issues), design, or past operating and maintenance history. PHMSA 
proposes to incorporate that self-executing statutory language within 
Sec.  192.605's list of prescribed content for the operations, 
maintenance, and emergency procedures of gas transmission, 
distribution, offshore gathering, and Types A, B, and C gathering 
pipelines. Affected operators may implement this proposed regulatory 
amendment by updating (to the extent they have not done so already in 
complying with the self-executing statutory mandate) their operating, 
maintenance, and emergency procedures to contain protocols guiding 
decision-making on whether replacement or remediation of a particular 
pipeline or its components would be a more durable and effective 
solution for remediating or preventing leaks that entail public safety 
and the environmental harms. PHMSA submits that operator protocols 
could (in addition to referencing the leak-prone materials identified 
in section 114 language) reference authoritative resources (e.g., State 
pipeline safety regulatory actions, PHMSA pipeline failure 
investigation reports and advisory bulletins, NTSB findings, or 
industry efforts) to assist in identifying pipelines known to leak and 
evaluating whether replacement or remediation would be more appropriate 
in each case, as discussed in the context of distribution pipeline 
leakage surveys in section IV.A.1. PHMSA invites comment on the value 
of either explicitly listing leak-prone materials (either within part 
192 or within periodically-issued implementing guidance). Comments on 
this question are especially helpful if they address the potential 
safety and environmental benefits and potential costs of a particular 
approach, including whether that approach would be technically 
feasible, cost-effective, and practicable.
    PHMSA's proposed revision to Sec.  192.605 addressing replacement 
of pipelines known to leak would apply only to gas transmission, 
distribution, and part 192-regulated gathering lines which are subject 
to the self-executing statutory mandate. The more general requirement 
from section 114 of the PIPES Act to have procedures addressing 
minimizing releases of natural gas are proposed for part 192-regulated 
gas pipeline facilities in Sec.  192.605, UNGSFs in Sec.  192.12, and 
LNG facilities in Sec. Sec.  193.2503 and 193.2605. That proposal is 
discussed in section IV.F. PHMSA solicits comment regarding whether any 
final rule in this rulemaking proceeding should extend the proposed 
revision addressing replacement of pipelines known to leak to gas 
pipeline facilities other than piping systems (in particular, part 193 
LNG facilities and UNGSFs). Comments on this question are especially 
helpful if they address the potential safety and environmental benefits 
and potential costs of a particular approach, including whether that 
approach would be technically feasible, cost-effective, and 
practicable.
3. Compressor Stations--Sec.  192.703(d)
    As described in section II.B of this NPRM, EPA has imposed methane 
emissions standards at 40 CFR part 60 for the oil and gas industry 
establishing fugitive emissions monitoring and repair requirements for 
gas transmission compressor stations and gas gathering boosting 
stations constructed, reconstructed, or modified after September 18, 
2015 (subpart OOOOa). EPA has also proposed (1) a new 40 CFR part 60, 
subpart OOOOb that would update standards for gas transmission 
compressor stations and gas gathering boosting stations installed, 
reconstructed or modified after November 15, 2021, and (2) nationwide 
emissions guidelines that would be

[[Page 31939]]

located at 40 CFR part 60, subpart OOOOc addressing methane emissions 
from oil and gas existing sources including fugitive emission 
components at existing gas transmission compression stations and gas 
gathering boosting stations that would not be subject to its proposed 
40 CFR part 60, subpart OOOOb standards.\243\
---------------------------------------------------------------------------

    \243\ See EPA SNPRM.
---------------------------------------------------------------------------

    Given EPA's existing and proposed robust methane emissions 
standards, PHMSA proposes a narrow exception from some of the proposed 
requirements for gas transmission and gas gathering compressor stations 
that would already be subject to monitoring and repair requirements 
within EPA's current 40 CFR part 60, subpart OOOOa regulations, 
proposed subpart OOOOb updates and subpart OOOOc methane emissions 
guidelines (as implemented through EPA-approved State plans with 
standards at least as stringent as EPA's emission guidelines in subpart 
OOOOc or implemented through a Federal plan).\244\ Specifically, PHMSA 
proposes exception from each of its requirements pertaining to leak 
repair (Sec.  192.703(c)), leakage survey and patrol (Sec. Sec.  
192.705 and 192.706), leak grading and repair (Sec.  192.760), ALDPs 
(Sec.  192.763) and qualification of leak detection personnel (Sec.  
192.769). Operators would, notwithstanding the exception from other 
elements of Sec.  192.760, remain obliged to retain records associated 
with leak repairs pursuant to Sec.  192.760(i) to ensure appropriate 
documentation of change and trend analysis on those facilities, as well 
as adequate documentation to support regulatory oversight activity by 
pertinent State and Federal regulatory authorities. To establish clear 
boundaries for the exception, PHMSA proposes that the exception would 
cover those components located within the first block valve entering or 
exiting the facility (exclusive of that block valve)--which valves mark 
the boundary of station overpressure protection pursuant to Sec.  
192.167.
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    \244\ Gas pipeline facilities that would be subject to this 
proposed exception would remain PHMSA-jurisdictional gas pipeline 
facilities otherwise subject to parts 191 and 192 requirements and 
PHMSA regulatory oversight.
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    EPA's proposed regime at 40 CFR part 60 for monitoring fugitive 
methane emissions from gas transmission compression stations and gas 
gathering boosting stations provides public safety and environmental 
protection comparable to PHMSA's proposals in this NPRM.\245\ EPA 
regulations at 40 CFR 60.5397a(g)(2) within subpart OOOOa require 
quarterly \246\ methane emissions monitoring surveys of leaks from all 
gas transmission compression and gas gathering boosting systems--more 
frequent than PHMSA's proposed leakage survey revisions for all but 
those facilities in HCAs within Class 4 locations. EPA requirements 
require those surveys be performed using leak detection equipment--
either optical gas imaging or another ``instrument'' (such as FID) with 
sensitivity of at least 500 ppm that complies with method DA in 
appendix A-7 to 40 CFR part 60--standards that are similar to the leak 
detection equipment contemplated by this NPRM. EPA regulations require 
an operator first attempt repair of any fugitive emissions so detected 
within 30 days and complete repairs within 30 days of that first 
attempt--equivalent to the 30-day repair timeline for grade 2 gas 
transmission pipeline leaks in HCAs and class 3 and class 4 locations 
proposed in this NPRM but more aggressive than the proposed 6-month 
timeline for repair of grade 2 leaks in non-HCA class 1 and class 2 
locations. And although the EPA's repair timelines may be less 
demanding than those proposed in this NPRM for grade 1 leaks, PHMSA 
understands that EPA's more frequent required surveys would ensure 
timely detection and remediation of leaks on gas transmission 
compression stations and gas gathering boosting stations. Further, 
allowing operators to direct compliance efforts toward EPA's regulatory 
regime rather than proposing additional requirements for EPA-regulated 
facilities ensures that operator resources are focused on methane 
emissions reduction rather than overlapping compliance frameworks.
---------------------------------------------------------------------------

    \245\ EPA's updated methane emissions new source performance 
standards in its proposed 40 CFR part 60, subpart OOOOb (new 
sources) and accompanying methane emissions guidelines at subpart 
OOOOc (existing sources) are not yet final; however, PHMSA considers 
the monitoring and repair elements of those proposals to be at least 
as protective of public safety and the environment as corresponding 
existing requirements 40 CFR part 60, subpart OOOOa. However, should 
proposed subparts OOOOb and OOOOc not be finalized, only gas 
transmission compression and gas gathering boosting stations subject 
to 40 CFR part 60, subpart OOOOa would be eligible for the exception 
proposed in this NPRM.
    \246\ While the final rule titled ``Oil and Natural Gas Sector: 
Emissions Standards for New, Reconstructed, and Modified Sources 
Review'' (85 FR 57018 (Sept. 14, 2020)) removed all methane 
standards from 40 CFR part 60, subpart OOOOa, including the 
quarterly monitoring and repair requirements for methane fugitive 
emissions at compressor stations at 40 CFR 60.5397a(g)(2), Congress 
subsequently disapproved that final rule by a joint resolution (Pub. 
L. 117-23) enacted pursuant to the Congressional Review Act (Pub. L. 
104-121). The president signed that joint resolution into law. As a 
result, the EPA's September 2020 final rule is treated as if it had 
never taken effect, and the methane standards in subpart OOOOa 
promogulated in 2016 remain in effect. See EPA's Q&A for more 
information. https://www.epa.gov/system/files/documents/2021-07/qa_cra_for_2020_oil_and_gas_policy_rule.6.30.2021.pdf.
---------------------------------------------------------------------------

    In the event that EPA's proposed regulations at subparts OOOOb and 
OOOOc are not in effect because they have not yet been finalized or for 
any other reason, the proposed exception would not apply and the leak 
detection, grading, and repair requirements proposed herein would apply 
to gas transmission and gas gathering compressor station facilities.
    PHMSA invites comment on the appropriateness of this proposed 
exception and the specific regulatory requirements within its proposed 
scope (to include comments regarding any potential regulatory gaps that 
may arise from this exception) for consideration in any final rule in 
this proceeding. Should stakeholders submit proposed alternatives 
content for this exception, those alternatives would be most helpful if 
they are supported by evaluation of the safety or environmental 
benefits, technical feasibility, cost-effectiveness, and 
practicability.
4. Grade 1 Leaks--Sec.  192.760(b)
    A grade 1 leak is the highest priority grade and represents an 
existing or probable hazard to persons, property, or an existing, grave 
hazard to the environment. A grade 1 leak is an urgent or emergency 
situation--for this reason, PHMSA proposes that operators must be 
required to take ``immediate and continuous'' action to eliminate the 
hazards to public safety and the environment. As soon as an operator 
determines a grade 1 leak exists, it must immediately dispatch 
personnel to address hazards to people or the environment and undertake 
other actions (including, but not limited to, those identified at 
proposed Sec.  192.760(a)(2), most of which track requirements 
elsewhere in PHMSA regulations) to minimize risks to public safety and 
the environment. The appropriate ``immediate and continuous action[s]'' 
taken by an operator would necessarily depend on the nature of the leak 
and pipeline operational and environmental conditions. For example, the 
``immediate and continuous action[s]'' required of the operator of a 
submerged, offshore pipeline in responding to a grade 1 leak on its 
system may entail different engineering actions or considerations than 
an operator of an onshore, non-buried, low-pressure pipeline with a 
grade 1 leak.

[[Page 31940]]

    PHMSA's proposed grade 1 leak criteria elaborate that, at a 
minimum,\247\ a grade 1 leak includes any of the following 
characteristics:
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    \247\ Operators may decide to adopt additional grade 1 criteria 
(or, for that matter, grade 2 criteria) supplementing the baseline 
criteria PHMSA proposes herein.
---------------------------------------------------------------------------

     Any leak that, in the judgment of operating personnel at 
the scene, is of sufficient magnitude to be an existing or probable 
hazard to persons or property, or a grave hazard to the environment;
     Any amount of escaping gas that has ignited;
     Any indication that gas has migrated into a building, 
under a building, or into a tunnel;
     Any reading of gas at the outside wall of a building, or 
areas where gas is likely to migrate to an outside wall of a building;
     Any reading of 80% or greater of the LEL in a confined 
space; \248\
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    \248\ Several of the grading criteria reference gas readings and 
are expressed as percent of the lower explosive limit (LEL). The LEL 
is the minimum required concentration of gas necessary for the gas 
to ignite when exposed to an ignition source. Percent LEL measures 
how close measured gas concentration is to reaching a flammable 
atmosphere. The LEL of natural gas is 5% gas by volume. However, the 
LELs for other flammable gases vary (e.g., the LEL for hydrogen gas 
is 4% gas by volume). A reading of 100% or more of LEL indicates 
that a flammable atmosphere is present, provided there is a 
sufficient concentration of oxygen present to support combustion and 
the upper explosive limit (UEL) is not reached. The percent LEL is 
typically measured during a leak investigation with a combustible 
gas indicator.
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     Any reading of 80% or greater of the LEL in a substructure 
(including gas associated substructures of a gas pipeline or non-
associated gas pipelines), from which gas would likely migrate to the 
outside wall of a building;
     Any leak that can be seen, heard, or felt by human senses; 
or
     Any leak reportable as an incident as defined in Sec.  
191.3.
    PHMSA's proposed grade 1 leak criteria resemble those in the GPTC 
Guide and, consistent with that framework, are intended to prioritize 
for immediate repair those leaks that pose a significant hazard to 
people and property. However, PHMSA proposes important differences 
designed to address gaps in safety and environmental protection. First, 
PHMSA proposes to characterize a grade 1 leak to include leaks with 
grave environmental harms. Including such leaks in the grade 1 leak 
criteria is consistent with the mandate for this NPRM in section 113 of 
the PIPES Act of 2020 and would reduce public safety risks. Any leak of 
methane from a gas pipeline system necessarily entails environmental 
harm proportional to the total release volume by contributing to 
climate change. PHMSA's proposed language therefore distinguishes 
between public safety risks (which can be existing or contingent under 
the historical GPTC Guide framework) and the certain environmental 
harms from leaks of methane and other gas. PHMSA proposes grade 1 
criteria scaled language (``grave hazard to the environment'') to 
acknowledge the magnitude of that harm from methane or other gas 
released from leaks can vary from one leak to the next. A leak 
satisfying one or more of its proposed grade 1 criteria would be a 
release of gas involving a risk of ignition that is sufficient to be an 
existing or probable future hazard to public safety, or release of 
sufficient volume that poses a grave hazard to the environment.
    Proposed Sec.  192.760(b)(1)(vi) also classifies as a grade 1 leak 
any reading of 80% LEL or greater in a substructure (subterranean 
structures too small for a human to enter) from which gas would likely 
migrate to the outside wall of a building. Unlike the GPTC Guide, the 
proposed criteria would include substructures associated with the 
operator's gas pipeline. A gas-associated substructure includes 
facilities such as small valve boxes and other vaults not intended for 
human entry. While it is not unusual for some gas to accumulate in gas-
associated substructure, a potentially explosive concentration of gas 
with the potential to migrate to nearby buildings is an immediate 
public safety hazard regardless of whether a substructure is associated 
with a gas pipeline or not. PHMSA also proposes conforming revisions to 
Sec.  192.3 to introduce definitions for the terms ``substructure,'' 
gas-associated substructure,'' and ``confined space'' to facilitate 
operator compliance and PHMSA and State regulatory oversight.
    Proposed Sec.  192.760(b)(1)(vii) would classify any leak that can 
be seen, heard, or felt as a grade 1 leak. In comparison, Table (3a) in 
the GPTC Guide limits this criterion to leaks that are in a location 
that may endanger the public or property. Applying the seen, heard, or 
felt criteria to leaks regardless of location ensures operator field 
personnel have a standard for classifying leaks that potentially cause 
significant environmental or safety consequences in the form of methane 
emissions and other pollutants. The visible indications of a gas leak 
may include for example, ground disturbances, a jet or vapor cloud of 
condensation, or blowing debris. A gas leak can also emit a hissing 
sound or, for larger leaks, sounds resembling a jet engine or train. 
Tactile indications of a leak include force from a jet of gas or 
vibrations in the pipe or soil. Each of these physical markers of a 
pipeline leak are typically more apparent on higher-pressure, larger 
volume leaks. PHMSA does not consider impacts to vegetation to be a 
definitive indication of a grade 1 leak for these purposes. However, an 
operator should consider if there are severe or widespread impacts to 
vegetation during a leakage investigation. Additionally, a leak on an 
offshore pipeline that is visible from the surface (i.e., bubbles or 
condensate sheen) would be classified as a grade 1 leak under this 
criterion.
    Lastly, PHMSA proposes that any leak reportable as an incident 
under part 191 would be classified as a grade 1 leak. The definition of 
``incident'' in Sec.  191.3 would include any event involving the 
release of gas from a pipeline that results in one or more of the 
following consequences:
     A death or personal injury necessitating in-patient 
hospitalization;
     Estimated property damage of $129,300, excluding the cost 
of lost gas, (adjusted for inflation for calendar year 2022); or
     Unintentional estimated gas release of 3 MMCF or more.
    This criterion would address gaps in the GPTC Guide's current grade 
1 leak criteria and would help ensure the repair of leaks that involve 
very large release volumes, or which are known to result in significant 
public safety and environmental harms. Further, if a previously 
detected leak later results in an incident causing significant safety 
and environmental consequences, then it almost certainly would have 
been an ``existing or probable hazard'' to persons and the environment 
at the time of detection and should have been graded and repaired 
accordingly. PHMSA invites comments on other potential criteria for 
identifying grade 1 leaks subject to immediate repair (for potential 
inclusion within a final rule in this proceeding), including the 
utility of adopting a quantified emissions rate criteria for grade 1 
leaks or other characteristics indicative of a grave environmental 
hazard, in addition to criteria proposed above. Comments are especially 
helpful to PHMSA when they identify a specific quantified emissions 
rate threshold or other specific characteristics supported by research 
or operational experience, along with the potential safety and 
environmental benefits and potential costs of a particular approach 
(including whether that approach would be technically feasible, cost-
effective, and practicable).

[[Page 31941]]

5. Grade 2 Leaks--Sec.  192.760(c)
    PHMSA also proposes to modify the GPTC Guide's characterization of 
grade 2 leaks to introduce a reference to environmental harms from 
those leaks: a grade 2 leak would be a leak which presents a probable 
future hazard to public safety or a significant hazard to the 
environment. PHMSA intends the proposed characterization of grade 2 
leaks to include those leaks that are not as urgent a hazard to either 
public safety or the environment as a grade 1 leak that it would 
require immediate and continuous action to eliminate the hazard, but 
which are significant enough to warrant timely repair.
    PHMSA proposes to classify a grade 2 leak as any leak (other than a 
grade 1 leak) with any of the following characteristics:
     A reading of 40% or greater of the LEL under a sidewalk in 
a wall-to-wall paved area that does not qualify as a grade 1 leak;
     A reading of 100% of the LEL under a street in a wall-to-
wall paved area that does not qualify as a grade 1 leak;
     A reading between 20% and 80% of the LEL in a confined 
space;
     A reading less than 80% of the LEL in a substructure 
(other than gas associated substructures) from which gas could migrate;
     A reading of 80% or greater of the LEL in a gas associated 
substructure from which gas is not likely to migrate;
     Any reading greater than 0% gas on a transmission or Types 
A or C gas gathering pipeline that does not qualify as a grade 1 leak;
     Any leak with a leakage rate of 10 CFH or more that does 
not qualify as a grade 1 leak;
     Any leak of LPG or hydrogen that does not qualify as a 
grade 1 leak; or
     Any leak that, in the judgment of operator personnel at 
the scene, is of sufficient magnitude to justify scheduled repair 
within 6 months or less.
    The proposal has important differences from the GPTC Guide that are 
designed to address gaps in safety and environmental protection. 
Specifically, PHMSA proposes to delete qualifying language in grade 2 
criteria to minimize ambiguity and ensure enforceability of the 
proposed repair standards. For illustration, in example A.B.2. in Table 
3b of the GPTC Guide, any reading of 100% LEL or greater under a street 
in a wall-to-wall paved area ``that has significant gas migration'' 
that is not a grade 1 is considered a grade 2 leak, however what 
constitutes ``significant'' gas migration is not defined or 
straightforward to enforce. Instead, the NPRM proposes to apply this 
standard to any such concentration of gas, which is itself hazardous to 
public safety or the environment, with any migration. Similarly, PHMSA 
does not propose to condition criteria for grade 2 leaks in 
substructure on the likelihood that ``gas would likely migrate creating 
a probable future hazard'' since a concentration of 80% or more of LEL, 
near the explosive limit, within a substructure is itself a probable 
future hazard to public safety. Additionally, PHMSA proposes to add a 
new criterion for all leaks from LPG systems that do not qualify as a 
grade 1 leak, consistent with an observation in the GPTC Guide that 
since LPG is heavier than air and does not dissipate like natural gas, 
``few [LPG] leaks can safely be classified as Grade 3.'' \249\ 
Likewise, PHMSA proposes that Grade 2 is the minimum priority grade for 
leaks of gaseous hydrogen. PHMSA understands these heightened safety 
requirements (compared to natural gas pipelines) are warranted because 
hydrogen is itself a flammable gas with a lower explosive limit and 
lower autoignition temperature than methane. And research summarized by 
the National Renewable Energy Laboratory indicates that overpressure 
blast risk in enclosed spaces and increases with the proportion of 
hydrogen within hydrogen/natural gas blends (particularly for 
concentrations above 50% hydrogen) and that, for transmission line 
ruptures, fatal injury risk increases as either proximity to the 
pipeline or the share of hydrogen in a natural gas blend 
increases.\250\
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    \249\ See Table 3 C in Appendix G-192-11A of the GPTC Guide.
    \250\ Melania, et al., National Renewable Energy Laboratory 
Technical Report TP-5600-51995, ``Blending Hydrogen into Natural Gas 
Pipeline Networks: A Review of Key Issues'' at 16-17 (Mar. 2013), 
https://www.nrel.gov/docs/fy13osti/51995.pdf.
---------------------------------------------------------------------------

    PHMSA also proposes to include a new emissions rate criterion for 
grade 2 leaks: any leak with an emissions rate equal to or greater than 
10 CFH would need to be classified as a grade 2 leak. PHMSA expects 
this criterion would ensure prioritized repair of such environmentally 
damaging leaks even if other grade 1 or grade 2 criteria are not met. 
PHMSA further notes that this proposed 10 CFH criterion is the same 
criterion used by PG&E's Super Emitter Program, which was based on data 
showing that methane leaks larger than 10 CFH represented only 2% of 
all leaks by number but over half of all emission volumes on PG&E's gas 
distribution system.\251\ PHMSA's selection of a 10 CFH emissions rate 
is consistent with the AGA et al. assertion that a significant share of 
emissions from natural gas pipeline systems can be caused by a 
relatively small proportion of leaks within each leak category.\252\ A 
2016 analysis by Brandt, et.al., of 15,000 emissions measurements from 
prior studies found that 5% of releases contributed to over half of 
total emissions volumes.\253\ An emissions rate of 10 CFH correlates to 
emissions of ca. 87,600 ft\3\ of methane (roughly 1,600 kg of methane) 
if left unrepaired for a year.\254\
---------------------------------------------------------------------------

    \251\ Rongere, Francois. ``Lessons Learned from the First Year 
of the Super Emitter Program.'' PG&E Nov. 5, 2019. https://www.epa.gov/sites/default/files/2019-12/documents/lessonslearnedfirstyearsuperemitterprogram_francoisrongere.pdf; 
Lamb, Brian K., et al. ``Direct Measurements Show DECREASING Methane 
Emissions from Natural Gas Local Distribution Systems in the United 
States.'' Environmental Science & Technology, vol. 49, no. 8, 2015, 
pp. 5161-5169., doi:10.1021/es505116p.
    \252\ AGA et al. at 5.
    \253\ Brandt AR, Heath GA, Cooley D. Methane Leaks from Natural 
Gas Systems Follow Extreme Distributions. Environ Sci Technol. 2016 
Nov 15;50(22):12512-12520. Doi: 10.1021/acs.est.6b04303. Epub 2016 
Oct 26. PMID: 27740745.
    \254\ The value here was calculated assuming a density of 
methane of 0.01926 kg/ft\3\.
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    PHMSA considered alternative approaches to its proposed emissions 
rate criterion but is concerned about their practicability. PHMSA 
invites comment on appropriate, alternative grade 2 emissions rate 
criterion thresholds and calculation methodologies--particularly 
considering the extent to which emissions from below ground leaks could 
be incorporated. PHMSA considered an approach employed by the 
Commonwealth of Massachusetts which categorizes methane leaks from 
natural gas pipelines as ``environmentally significant'' grade 3 leaks 
if they have a barhole reading of 50% gas in air or higher, or a 
measured leak migration extent of 2,000 square feet or greater.\255\ In 
Massachusetts, leaks with a migration extent from 2,000 to 10,000 
square feet must be repaired within 2 years and leaks with a migration 
extent greater than 10,000 square feet must be repaired within 12 
months. This method--which measures the extent of below-ground 
migration as a proxy for the release rate--could be a relatively 
straightforward means to classify large-volume, below-ground leaks 
(particularly for gas distribution systems). However, since gas 
migration can be affected greatly by soil and weather conditions, the 
2,000 square feet element of this approach may not be

[[Page 31942]]

appropriate for a nationwide standard applicable to natural gas 
distribution, gathering and transmission pipelines across a diversity 
of operational and environmental conditions, as well as other gases 
transported in part 192-regulated gas pipelines. Variations in gas 
migration due to operational and site-specific environmental 
considerations may then result in missing or over-stating large-volume 
leaks. PHMSA also considered a relative emissions criterion, such as 
requiring an operator to repair leaks with an emissions quantity larger 
than the median leak rate on the operator's system by release rate 
(estimated with an advanced mobile leak detection technology, high-flow 
sampler, or equivalent method) or measured gas concentration. While 
that approach would be comparatively simple to implement, it could 
result in inconsistent repair requirements across operators as well as 
perverse consequences: an operator with a well-designed and maintained 
system with few large-volume leaks would have the same proportion of 
priority repairs as an operator with poor maintenance practices or 
significant mileage of leak-prone pipe such that the latter operator 
could defer repair of potentially large leaks.
---------------------------------------------------------------------------

    \255\ 220 CMR 114.07(1)(a).
---------------------------------------------------------------------------

    PHMSA invites comments on the proposed criteria for identifying 
grade 2 leaks that constitute a significant hazard to the environment, 
including the practicability of using a specified emissions rate 
criterion (and whether 10 CFH is the appropriate emissions rate for 
grade 2 leaks), for potential inclusion within a final rule in this 
proceeding. Comments on this question are especially helpful if they 
identify a specific emissions rate, gas concentration, or other 
measurement supported by research or operational experience for 
identifying leaks that should be subject to shorter repair timelines 
due to their potential environmental impacts over time. PHMSA further 
invites comments on how quantification of emissions rates are or could 
be integrated into operator's leak survey, investigation, and 
management procedures. Finally, PHMSA seeks comments on whether other 
criteria could be used to identify leaks with significant environmental 
harm. Comments on these questions are especially helpful to PHMSA when 
they identify the potential safety and environmental benefits and 
potential costs of a particular approach (including whether that 
approach would be technically feasible, cost-effective, and 
practicable).
    PHMSA also proposes a minimum grade 2 classification for any leak 
on a gas transmission or Type A or C gathering pipeline. The GPTC Guide 
identifies leaks on pipelines operating at 30% SMYS or greater (i.e., 
most gas transmission lines) in Class 3 or Class 4 locations, other 
than grade 1 leaks, as grade 2 leaks and assigns a six-month repair 
requirement. This NPRM proposes to apply this repair timeline to all 
gas transmission pipelines, and Types A and C gathering pipelines 
because of the similar design and operating characteristics--and 
therefore public safety and environmental risk profiles--of those 
pipelines. In particular, transmission and Type A and Type C gathering 
lines operate at a high stress level and therefore, as described in 
section II.D.3, there is a correspondingly higher risk of a rupture if 
the condition that caused the leak deteriorates further. PHMSA does not 
propose a similar requirement for offshore gas gathering pipelines 
because many of those pipelines operate far from the general public and 
at lower pressures than gas transmission and Type A gathering pipelines 
such that their public safety and environmental risks are 
distinguishable.
    PHMSA also proposes more timely repair of grade 2 leaks than 
contemplated by the GPTC Guide, which requires operators to repair such 
leaks within 12 months of detection. Specifically, PHMSA proposes a 
default requirement for grade 2 leak repairs to be completed within the 
earlier of six months of detection, or the repair timeline specified in 
the operator's procedures or IM plan. The accelerated default repair 
timeline would better address the significant public safety and 
environmental risks grade 2 leaks entail. In addition, operators 
subject to the six-month default repair timeline for grade 2 leaks 
would be required to re-evaluate each grade 2 leak every 30 days until 
the leak has been repaired, which is intended to ensure that those 
leaks do not degrade into a grade 1 leak.
    PHMSA proposes shorter repair deadlines for grade 2 leaks that are 
known on or before the effective date of a subsequent final rule in 
this proceeding. Further, PHMSA would require these leaks be repaired 
within one year from the publication date, consistent with the 12-month 
repair schedule in the GPTC Guide some operator practices may currently 
reference. Additionally, due to the greater public safety risks of a 
grade 2 leak from either a gas transmission or Type A gathering 
pipeline, each within HCAs or densely populated Class 3 or Class 4 
locations, PHMSA proposes to require that these leaks be repaired 
within 30 days of detection, with an operator making continuous effort 
to monitor and repair the leak and eliminate the potential hazard if 
repairs cannot be completed within the prescribed timeline. As 
previously discussed in section II.C., leaks on gas transmission line 
pipe are less common than leaks on gas distribution pipeline pipe. 
However, a leak on a gas transmission or Type A gathering pipeline will 
likely result in greater release volumes and higher risk of ignition 
than distribution or Type B gathering lines due to the higher operating 
pressures and flow volumes typical of transmission and Type A gathering 
pipelines. The higher operating stress level on gas transmission and 
Type A gathering pipelines also entail a higher risk of rupture from 
degradation of leaks over time.
    Lastly, PHMSA proposes to require each operator's leak grading and 
repair procedures to include a methodology for prioritizing grade 2 
leak repairs, including criteria for determining leaks that must be 
repaired within 30 days or less. PHMSA's proposed criteria are based on 
calendar days rather than the working days under the GPTC Guide, which 
is consistent with existing guidance in Table 3a of the GPTC Guide. The 
operator's methodology must also include an analysis of the estimated 
volume of leakage since detection or the date of the last survey 
(whichever is earlier), migration of gas emissions, proximity of the 
leaking gas to buildings and underground structures, the extent of 
pavement, and soil types and conditions that affect the possibility for 
hazardous gas migration, such as frost conditions or soil moisture. 
This approach is consistent with the guidance in the GPTC Guide that 
certain grade 2 leaks justify repair on an accelerated schedule, and 
further mandates operators to consider safety and environmental 
protection when prioritizing repair efforts.
6. Grade 3 Leaks--Sec.  192.760(d)
    PHMSA proposes that any leak that does not meet the criteria for a 
grade 1 or a grade 2 leak be classified as a grade 3 leak, which would 
be the lowest priority leak category. PHMSA has provided a non-
exhaustive list of grade 3 criteria, including the following: a 
positive reading of less than 80% LEL in gas-associated substructures 
from which gas is unlikely to migrate, any positive reading under a 
street in an area without wall-to-wall pavement where gas is unlikely 
to migrate to the outside wall of nearby buildings, or a

[[Page 31943]]

gas reading less than 20% LEL in a confined space. These examples are 
derived from the GPTC Guide, with additional clarifying language, 
``from which gas is unlikely to migrate,'' consistent with PHMSA's 
understanding of the purpose of the pertinent GPTC Guide example.
    The GPTC Guide and most State requirements do not define leak 
repair deadlines for grade 3 leaks. However, even a small leak can 
result in significant emissions and harm to the environment and public 
safety if it is allowed to release indefinitely without repair. 
Moreover, even small leaks have the potential to progress to more 
serious integrity incidents and failures, such that a grade 3 leak 
could develop into a more hazardous condition if ignored indefinitely. 
PHMSA therefore proposes a 24-month repair deadline for grade 3 leaks 
detected after the effective date of any final rule in this proceeding; 
this repair timeline would ensure timely repair of leaks while 
facilitating operator prioritization of repairs of higher-risk grade 1 
and 2 leaks. This proposed repair schedule is 12 months more aggressive 
than the 36-month deadline adopted by the State of Texas, but 
consistent with other standards such as the delayed repair permitted 
for fugitive emissions monitoring in the EPA 40 CFR OOOOa standards for 
repairs where immediate repair is not feasible.\256\ On the other hand, 
some States have more aggressive timelines, suggesting that the 
proposed timeline remains feasible for repair of buried pipeline 
facilities. For example, Missouri requires repair of ``class 2 leaks'' 
\257\ within 45 days, unless the pipeline is scheduled for replacement 
within 1 year.\258\ The 24-month repair deadline further ensures that 
all leaks discovered during a leakage survey are repaired prior to the 
next leakage survey (the longest proposed survey interval is once every 
3 years for distribution pipelines outside of business districts, see 
proposed Sec.  192.723), which would better prevent further growth in 
the backlog of unrepaired leaks than a 36-month repair deadline. Due to 
the likely large number of existing grade 3 leaks across the U.S., 
exemplified by the backlog of 10,000 unrepaired leaks on 11 New York 
distribution systems described in section II.D.3,\259\ PHMSA proposes a 
repair deadline of 3 years after the publication date of the final rule 
for grade 3 leaks known to exist on or before the effective date of any 
final rule. This repair deadline is intended to give operators time to 
prioritize timely repair of higher-priority, previously-known-to-exist 
grade 2 leaks, while still ensuring timely repair of grade 3 leaks 
known to exist at the time a final rule publishes. Additionally, PHMSA 
proposes to require that each grade 3 leak must be re-evaluated at 
least once every six months until the repair of the leak is completed. 
The re-evaluation is designed to assess if the leak or the leak 
environment has changed in a way that may justify an upgrade to a grade 
1 or grade 2 leak.
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    \256\ 40 CFR 60.5397a(h)(3).
    \257\ This term is unrelated to class 2 locations set forth in 
49 CFR 192.5.
    \258\ 20 [Missouri] Code of State Regulations 4240-
40.030(14)(C)(2).
    \259\ State of New York Department of Public Service, Case 21-G-
0165, ``2020 Pipeline Safety Performance Measures Report'' at 
Appendix K (June 17, 2021).
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    Lastly, as previously discussed in section II.E of this NPRM 
certain types of pipe materials cause a disproportionate number of 
leaks. In particular, pipe and fittings made of cast iron, unprotected 
steel, wrought iron, and historic plastics with known issues are more 
likely to leak than coated and protected steel and modern plastics. 
Replacing these pipelines and other pipelines known to leak can be an 
effective, long-term solution to systematic leak susceptibility for 
such pipelines. For example, in AGA's presentation at PHMSA's May 2021 
public meeting on methane leak detection and repair, they noted that 
operators cast iron and bare steel distribution pipelines accounted for 
approximately 75 percent of reported leak repairs.\260\ These 
replacement programs multiply benefits by eliminating both existing and 
future leaks. To accommodate pipe replacement programs, particularly on 
leak prone facilities, PHMSA proposes to allow that a grade 3 leak may 
be monitored rather than repaired if the leaking pipeline is scheduled 
for replacement or abandonment, and is in fact replaced or abandoned, 
within five years from the date of detection of the leak. This five-
year timeline is intended to accommodate the time necessary for 
planning, permitting, engineering, design, and construction of pipeline 
replacement projects. This proposed timeline is consistent with PHMSA's 
Natural Gas Distribution Infrastructure Safety and Modernization Grants 
program, which permits applicants to elect a period of performance of 
up to 5 years for pipe replacement projects.\261\ Due to the heightened 
potential hazards to public safety and the environmental, PHMSA does 
not propose a similar allowance for grade 1 and grade 2 leaks.
---------------------------------------------------------------------------

    \260\ Sames, Christina. ``Pipeline Leak Detection, Leak Repair, 
and Methane Emissions.'' AGA. May 5, 2021. https://primis.phmsa.dot.gov/meetings/FilGet.mtg?fil=1139.
    \261\ See PHMSA, ``Frequently Asked Questions: FY 2022 Natural 
Gas Distribution Infrastructure Safety and Modernization Grant 
Notice of Funding Opportunity (NOFO)'' (July 29, 2022). FAQ 67 at 
page 16. https://www.phmsa.dot.gov/grants/pipeline/ngdism-nofo-faqs.
---------------------------------------------------------------------------

    PHMSA seeks comments on the proposed repair timelines for grade 3 
leaks (for potential inclusion within a final rule in this proceeding), 
including whether shorter repair timelines would be appropriate for 
grade 3 leaks existing as of publication of a final rule, or for grade 
3 leaks eliminated by pipeline replacement. Comments on these questions 
are especially helpful when they provide specific suggestions supported 
by research or operational experience, along with the potential safety 
and environmental benefits and potential costs of a particular approach 
(including whether that approach would be technically feasible, cost-
effective, and practicable).
7. Post-Repair Inspection--Sec.  192.760(e)
    PHMSA proposes to specify that a leak repair may only be classified 
as complete if the operator obtains during a post-repair inspection a 
gas concentration reading of 0% gas by volume at the leak location. The 
equipment used in leak investigations, including this post-repair 
inspection, must meet the proposed 5 ppm sensitivity standards in Sec.  
192.763(a)(1)(ii). This proposed inspection requirement ensures that 
the repair was effective and provides a definite, final repair date for 
operator records. For leaks that are eliminated by routine 
maintenance--such as cleaning, lubrication, or adjustment--a post-
repair inspection would not be required for any leaks from aboveground 
facilities or for grade 3 leaks from other facilities.
    PHMSA proposes that an inspection must occur between 14 and 30 days 
after the date of the repair. PHMSA intends the minimum interval before 
the first repair inspection to help ensure that the inspection 
accurately reflects the condition of the repair, since repairs may have 
a 0% reading at the moment of repair, but gas may leak over time from 
an incomplete repair or the repair may fail in a 14-day period. PHMSA 
is proposing a 30-day maximum to align with its proposed 30-day 
monitoring requirement for grade 2 leaks. If the operator is unable to 
achieve a 0% reading and determines that a grade 1 or 2 condition 
exists, PHMSA proposes that the operator must take immediate and 
continuous action to re-evaluate and remediate the repair so as to

[[Page 31944]]

eliminate the leak. This proposed repair timeline could accelerate the 
repair of some grade 2 leaks. An accelerated timeline may be warranted 
because an incomplete or failed first attempt at leak repair could 
inhibit subsequent efforts to properly repair the leak. The proposed 
rule requires that if the post-repair inspection indicates a gas 
reading of greater than 0% gas and a grade 1 or grade 2 condition does 
not exist, the operator must remediate and re-inspect the repair every 
30 days until it obtains a gas concentration reading of 0%. In this 
situation, remediation of a repair of a grade 3 leak would be completed 
before the initial repair deadline of 24 months from the date of 
initial detection. If a grade 3 condition exists during a post-repair 
inspection for a leak that was originally a grade 1 or grade 2 leak at 
the time of detection, the operator may consider downgrading the leak 
under proposed Sec.  192.760(g), in which case the repair deadline is 
determined by the repair deadline proposed under Sec.  192.760(h).
8. Upgrading and Downgrading--Sec.  192.760 (f) and (g)
    PHMSA proposes to establish requirements for when and how a leak 
may be upgraded to a higher-priority grade or downgraded to a lower-
priority grade. Section 192.760(f) would require that if an operator 
receives information that a higher-priority grade condition exists on a 
previously graded leak, the operator must upgrade the leak to that new 
grade. For a leak that is upgraded, the repair deadline is the earlier 
of the remaining repair deadline for the original grade, or the repair 
deadline under the new leak grade measured from the date the operator 
receives the information that a higher-priority grade condition exists. 
This proposed approach would provide certainty regarding the repair 
deadline for an upgraded leak, while avoiding the perverse consequence 
that upgrading a leak would allow a more permissive repair schedule.
    PHMSA also proposes to allow downgrading a leak grade only if a 
repair has been attempted. This approach would allow downgrading a leak 
only if the operator performed a temporary repair or attempted a 
permanent leak repair but did not obtain a 0% gas reading during the 
post-repair inspection under proposed Sec.  192.760(e). This would 
prevent practices such as downgrading a leak after venting until gas 
concentration falls below a grade 1 or grade 2 criteria, without an 
effort to repair the leak itself. If a leak is downgraded, PHMSA 
proposes the time period for repair would be the remaining time allowed 
for repair for the downgraded leak measured from the time the leak was 
first detected--an approach PHMSA expects would incentivize timely 
completion of downgraded repairs and prevent extension of repair 
timelines through pretextual attempts at permanent repair.
9. Extension of leak repair--Sec.  192.760(h)
    PHMSA proposes to allow an extension of the repair deadline 
requirements for individual leaks on a case-by-case basis. Any 
extension requires notification to, and review by, PHMSA pursuant to 
the procedures in Sec.  192.18. Leak repair extensions under Sec.  
192.760(h) may be requested only if (1) the leak repair pursuant to an 
alternative schedule would not result in increased public safety risk, 
and (2) the operator can demonstrate that the prescribed repair 
schedule is impracticable, an alternative repair schedule is necessary 
for safety, or remediation within the specified time frame would result 
in the release of more gas to the environment than would otherwise 
occur if the leak were allowed to continue. For example, an alternative 
repair schedule may be warranted if remediation within the timeframe 
proposed in this NPRM would result in the release of more gas to the 
environment from blowdown--delayed repair could minimize emissions by 
coordinating blowdowns with other maintenance activity, while offering 
the safety benefit of fewer emissions that could ignite. PHMSA proposes 
to limit the extensions to grade 3 leaks, which inherently pose lower 
risks to public safety and the environment than grades 1 and 2 leaks. 
The notification to PHMSA would need to include a description of the 
leak, the leaking pipeline, the leak environment, any proposed 
monitoring and extended repair schedule, the justification for an 
extended repair schedule, and proposed emissions mitigation methods.
10. Recordkeeping--Sec.  192.760(i)
    PHMSA proposes certain recordkeeping requirements for leak 
detection, investigation, grading and repair activity. Section 
192.760(i) would describe recordkeeping requirements associated with 
leak grading and repair; PHMSA proposes that records documenting the 
complete history of investigation and grading of each leak prior to 
completion of the repair would need to be retained until five years 
after the date of the final post-repair inspection performed under 
proposed paragraph Sec.  192.760(e). Pertinent records would include 
documentation of grading monitoring, inspections, upgrades, and 
downgrades. PHMSA also proposes that records associated with the 
detection, remediation, and repair of each leak must be maintained for 
the life of the pipeline. This permanent recordkeeping would apply to 
both piping and non-piping portions of the pipeline. Should leak 
detection occur during a patrol, survey, inspection, or test, the 
pertinent portion of documentation for that patrol, survey, inspection, 
or test would need to be retained pursuant to proposed Sec.  
192.760(i). These proposed documentation requirements would support 
periodic evaluation and improvement of their ALDPs pursuant to proposed 
Sec.  192.763(a)(4) as well as regulatory oversight activity by PHMSA 
and its State partners.

D. Qualification of Leakage Survey, Investigation, and Repair 
Personnel--Sec.  192.769

    Proposed Sec.  192.769 would require that operator personnel 
engaged in leakage surveys, and the investigation and repair of leaks 
discovered on each of gas transmission, distribution, offshore 
gathering, and Type A regulated onshore gathering \262\ pipelines are 
subject to the personnel qualification requirements at part 192 in 
performing those activities. PHMSA proposes to clarify that leakage 
surveys, investigation, and repair activities are ``covered tasks'' 
under part 192, subpart N and therefore covered by operator 
qualification requirements in that subpart. These operations and 
maintenance functions are critical to ensuring the proper operation and 
integrity of gas pipelines, and therefore meet the criteria for the 
four-part test for defining covered tasks in Sec.  192.801(b) (tasks 
that are performed on a pipeline facility; are operations or 
maintenance tasks; are required by part 192; and affect the operation 
or integrity of the pipeline). Therefore, the proposed revision would 
help ensure baseline regulatory requirements for personnel 
qualification are met when performing those activities.
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    \262\ PHMSA regulations at Sec.  192.9(c) allow operators of 
Type A gas gathering pipeline to employ less comprehensive programs 
in satisfying subpart N personnel qualification requirements than 
employed by certain other part 192-regulated gas pipelines. PHMSA is 
not proposing a different approach for personnel qualifications with 
respect to personnel conducting leakage surveys and investigation 
and repair of leaks on Type A gas gathering pipelines.
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    PHMSA understands that the proposed personnel qualification 
requirements discussed above would be reasonable, technically feasible, 
cost-effective, and practicable for affected gas pipeline operators. 
PHMSA understands

[[Page 31945]]

that some affected operators may already have adopted (either 
voluntarily or in response to State or Federal requirements) compliant 
training and personnel practices, or would be able to adapt existing 
practices with minimal effort--particularly as ensuring personnel 
employed in conducting leakage surveys, inspection, and repair 
activities is a practice that reasonably prudent operators would adopt 
in ordinary course to protect public safety and the environment from 
release of pressurized (natural, flammable, corrosive, and toxic) gases 
transported in their pipelines and minimize loss of commercially 
valuable commodity. Viewed against those considerations and the 
compliance costs estimated in the Preliminary RIA, PHMSA expects its 
proposed amendments will be a cost-effective approach to achieving the 
commercial, public safety, and environmental benefits discussed in this 
NPRM and its supporting documents. Lastly, the NPRM's proposed 
compliance timelines--which are based on an effective date of six 
months after the publication date of a final rule in this proceeding 
(which would necessarily be in addition to the time since issuance of 
this NPRM)--would provide operators ample time to develop and provide 
the requisite training for their personnel (or otherwise obtain access 
to qualified personnel) and manage any related compliance costs. PHMSA 
seeks comments on whether, within a final rule in this proceeding, it 
would be appropriate to apply the proposed operator qualification 
requirements in Sec.  192.769 to Type B and Type C regulated onshore 
gas gathering lines or UNGSFs, which are not currently required to 
comply with subpart N. Comments on this question are especially helpful 
if they address the potential safety and environmental benefits and 
potential costs of that approach, including whether that approach would 
be technically feasible, cost-effective, and practicable. For gas 
gathering pipelines, this could entail subjecting Type B and applicable 
Type C gathering pipelines to simplified subpart N requirements similar 
to Type A lines in Class 1 locations and could either apply generally 
to all covered tasks, or only for leak detection, grading, and repair 
activities.

E. Reporting and National Pipeline Mapping System--Sec. Sec.  191.3, 
191.9, 191.11, 191.17, 191.19, 191.23, and 191.29

    PHMSA proposes new and revised reporting requirements to collect 
more data on pipeline leaks and other emissions. The most significant 
proposed revisions would create a large-volume gas release report to 
supplement existing incident reporting requirements. As is the case for 
incident reports, this requirement would apply to any gas pipeline 
facility covered under part 191, including jurisdictional storage and 
part 193 LNG facilities. Additionally, PHMSA proposes to revise the gas 
transmission, offshore gathering, and Types A, B, and C gathering, and 
distribution annual report forms to include each of (1) estimated 
aggregate emissions from all leaks existing on the system within the 
calendar year by grade (including emissions within the calendar year 
from leaks discovered in prior years), (2) other methane emissions by 
source category, and (3) the number of leaks detected and repaired by 
grade. PHMSA solicits comments on the potential utility of requiring 
operators to report more granular leak data, such as individual leak 
location, individual leak emissions, or individual leak repair timing, 
in addition to the information described above. Comments on this 
question are especially helpful if they address the potential safety 
and environmental benefits and potential costs of a particular 
approach, including whether that approach would be technically 
feasible, cost-effective, and practicable.
    Existing Sec.  191.3 defines an incident as a release from a gas 
pipeline facility that results in death or serious injury, property 
damage of $122,000 \263\ or more in calendar year 2021, or an 
unintentional release of 3 MMCF or more of gas. While incident reports 
provide valuable information on major emissions events with critical 
safety consequences, existing incident reporting criteria and the 
exclusion of intentional releases from reporting requirements means the 
current reporting scheme does not capture data on many significant 
emissions events.
---------------------------------------------------------------------------

    \263\ Adjusted for inflation on an annual basis.
---------------------------------------------------------------------------

    PHMSA therefore proposes at Sec.  191.19 to require a new report 
for intentional and unintentional releases with a volume of 1 MMCF or 
greater, excluding certain events that had been reported as incidents 
under Sec. Sec.  191.9 or 191.15. For illustration, routine leaks with 
an emissions rate of 10 CFH consistent with the proposed grade 2 
emissions criteria at Sec.  192.760, would not be reported individually 
under this section if they are repaired within the proposed repair 
schedule (note that a count of all leaks would be reported on annual 
reports), but larger leaks exceeding 100 kg/hr. ``super-emitter'' 
criteria contemplated by the EPA in their December 6, 2022 supplemental 
notice of proposed rulemaking \264\ would be reported if they were not 
promptly repaired such that their aggregate emissions were below the 1 
MMCF threshold. Blowdowns of high-pressure lines without mitigation 
measures such as those proposed in Sec.  192.770 may also meet the 1 
MMCF threshold depending on the pressure and volume of the blowdown 
segment. Operators would be required to submit a report within 30 days 
from the date that a release known at detection to be 1 MMCF or more 
was detected, or 30 days from the date that a previously detected 
release became reportable. If the time the leak started is unknown, 
operators should base the calculation based on estimated release volume 
from the date of the most recent leakage survey. PHMSA proposes an 
exception from Sec.  191.23 safety-related condition reporting 
requirements for events that are reported as large-volume gas releases. 
This proposed exception for large-volume incident reports would be 
consistent with the existing exception at Sec.  191.23(b) for events 
reported as incidents.
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    \264\ EPA, ``Standards of Performance for New, Reconstructed, 
and Modified Sources and Emissions Guidelines for Existing Sources: 
Oil and Natural Gas Sector Climate Review,'' 87 FR 74702, 74707 
(Dec. 6, 2022).
---------------------------------------------------------------------------

    These new, large-volume gas release reports would provide valuable 
information on the primary sources and causes of vented emissions and 
the causes of large-volume leaks that do not qualify as incidents, 
addressing information gaps in the current incident reporting 
requirements. First, information on vented emissions is not currently 
collected on incident or annual report forms. The new report would 
provide PHMSA and other interested stakeholders information on the 
causes, consequences, and frequency of intentional, large-volume, 
vented emissions to provide both regulators and operators the 
information necessary to prevent reoccurrence. That information would 
be also particularly useful for PHMSA and State regulatory authorities 
in ensuring operator compliance with the self-executing mandate within 
section 114 of the PIPES Act of 2020 for operators to update their 
inspection and maintenance procedures to provide for minimization of 
releases of gas from their pipeline facilities. Second, PHMSA's 
proposed 1 MMCF threshold for the new large-volume gas release report 
is significantly lower than the 3 MMCF threshold required under the 
current incident reporting regulations, allowing PHMSA to collect 
detailed

[[Page 31946]]

cause and consequence information on large-volume, intentional and 
unintentional releases that may not be collected on incident reports. 
PHMSA solicits comment on whether alternative reporting thresholds for 
either large volume gas releases or incidents, including thresholds 
below 1 MMCF, would provide higher-quality information than PHMSA's 
proposed 1 MMCF threshold. Comments on this question are especially 
helpful if they address the potential safety and environmental benefits 
and potential costs of a particular approach, including whether that 
approach would be technically feasible, cost-effective, and 
practicable.
    PHMSA proposes to include the above information on a new report 
rather than by revising the incident definition at Sec.  191.3 to 
collect focused information on fugitive and vented emissions that do 
not satisfy incident reporting criteria. Operators of all gas pipeline 
facilities would remain required to submit incident reports if 
unintentional releases reported under this new requirement subsequently 
satisfy incident reporting criteria. Operators who have already 
submitted an incident report would not need to file a large-volume gas 
release report under Sec.  191.19 for the same event so long as the 
release volume in the incident report is within 10 percent of the total 
release volume on cessation of the release. PHMSA intends for the 
large-volume gas release reporting requirement to extend to Type R gas 
gathering pipelines to inform PHMSA's consideration of whether fugitive 
and vented emissions from those pipeline facilities warrant extension 
of part 192 requirements.
    PHMSA proposes to clarify what is considered property damage for 
the purpose of determining whether a release is reportable as an 
incident pursuant to Sec. Sec.  191.9 or 191.15. Specifically, PHMSA 
proposes revision of the definition of ``incident'' at Sec.  191.3 to 
exclude, when calculating estimated property damage, costs associated 
with each of obtaining permits and removal or replacement of 
infrastructure undamaged by the event (e.g., pavement needed for access 
and repair activity) in connection with an event. This change would 
respond to NAPSR Resolution 2021-01, ``A Resolution Seeking a 
Modification of PHMSA's Instructions for Incident Reporting for Gas 
Distribution, Gas Transmission, and Gas Gathering Systems,'' \265\ 
which concerns how to classify overall secondary damage beyond the 
primary damage from an incident. Operators would still report these 
costs as incident consequences on the applicable incident report forms; 
however, they should not be included in the calculation of property 
damage for determining whether a release is reportable as an incident.
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    \265\ http://www.napsr.org/resolutions.html.
---------------------------------------------------------------------------

    PHMSA also proposes changes to the gas distribution, transmission, 
offshore gathering, and regulated onshore gas gathering annual reports 
required by Sec. Sec.  191.11 and 191.17, consistent with other 
proposed changes regarding leak grading and repair on those facilities 
and to collect information on estimated total emissions from each of 
(1) leaks existing on the operator's system during the calendar year by 
grade and (2), other emissions by source category. The source 
categories generally mirror the categories in the GHGI, as summarized 
in section II.C.2. While existing annual report forms include limited 
data on leaks repaired in the preceding year, they lack other data--
including the number and grade of leaks detected in the preceding year, 
the grade of leaks repaired in the preceding year, and estimated 
release volumes from those leaks--important for PHMSA and State 
regulators to understand the frequency of leaks, the significance for 
public safety and the environment from those leaks, and adequacy of 
operator leak detection and repair programs. PHMSA therefore proposes 
to revise the annual report forms for operators of gas distribution, 
offshore gathering, regulated onshore gathering, and transmission 
pipeline facilities to collect data on each of the following: the 
number of leaks detected and repaired by grade (see proposed Sec.  
192.760); the estimated aggregate emissions from all existing leaks 
(whether detected in the reporting year or not) by grade, and estimated 
emissions from other sources by source categories. PHMSA further 
proposes that, because this NPRM does not provide for leak grading 
requirements for LNG facilities, operators of those facilities would 
need to report data on each of the number of methane leaks detected and 
repaired during the annual reporting period pursuant to proposed Sec.  
193.2624, the number of unrepaired leaks at the end of the annual 
reporting period, and estimated fugitive methane emissions (each by EPA 
GHGRP source category) from all methane leaks identified pursuant to 
proposed Sec.  193.2624. PHMSA is not proposing similar enhanced annual 
reporting requirements for Type R gathering pipelines because those 
facilities would not be subject to the leak grading and repair 
requirements at Sec.  192.760. However, PHMSA sees value in reviewing 
the results of recently-adopted incident and annual reporting 
requirements for those pipelines under the Gas Gathering Final Rule, as 
well as the large-volume gas release reporting requirements proposed 
herein, to inform a path forward regarding expanding annual reporting 
requirements for Type R pipelines.
    For emissions reporting, PHMSA proposes operators provide aggregate 
emissions estimate for leaks by grade. PHMSA also proposes to collect 
estimated annual emissions by source category, which includes both 
leaks, incidents, and vented emissions. The source categories generally 
mirror the categories in the GHGI and as summarized in section II.C.2. 
This approach would ensure that both EPA and PHMSA have high-quality 
leak emissions data to support their distinguishable, but mutually-
reinforcing, regulatory responsibilities. For PHMSA aggregate emissions 
data provided on a per-leak grade basis would be particularly useful in 
informing future decision-making calibrating part 192 safety 
requirements based on an evolving understanding of the safety and 
environmental hazards posed by different grades of leaks. Similarly, 
information on other emissions would better inform Federal, State, and 
operator efforts to minimize avoidable vented emissions, which is 
required under section 114 of the PIPES Act of 2020. PHMSA would 
require that, in developing aggregate emissions estimates, operators 
would employ direct measurement and/or top-down methodologies along the 
lines of those discussed in section III.C.2 above.\266\
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    \266\ PHMSA would also consider estimated emissions 
methodologies employed by EPA-qualified third-party notifiers in 
reporting leaks under EPA's super-emitter response program proposals 
within its supplemental notice of proposed rulemaking issued under 
RIN 2060-AV16. See EPA SNPRM.
---------------------------------------------------------------------------

    PHMSA also proposes to require operators to submit geospatial data 
about offshore gas gathering and Type A, Type B, and Type C gathering 
pipelines to the NPMS. The NPMS is a geographic information system 
(GIS) that contains the locations and related attribute data for a 
variety of pipeline facilities. The NPMS was established via a self-
executing requirement codified in 49 U.S.C. 60132; while that statutory 
mandate excluded distribution and gathering lines, PHMSA has authority 
elsewhere in the Federal Pipeline Safety Laws at 49 U.S.C. 60117(c) to 
collect safety data for gathering pipelines to inform whether and how 
to provide

[[Page 31947]]

regulatory oversight of those facilities. Pipeline safety 
stakeholders--including journalists, operators, emergency responders, 
excavators, elected officials, public interest advocates, and PHMSA and 
State regulators--use the NPMS to obtain important pipeline-safety 
related information, including the locations of pipelines and related 
infrastructure, the names and contact information of pipeline 
operators, and other attributes of pipelines such as commodities 
transported and diameter.\267\ In particular, access to gathering 
pipeline geospatial data on NPMS would reinforce damage prevention 
programs required under Sec.  192.614. Emergency responders often use 
the NPMS to identify pipelines in the vicinity of reported leaks and 
contact relevant operators. Emergency responders and pipeline operators 
also use the NPMS while conducting drills and exercises to support 
operators' emergency response plans. The requirement to submit data to 
the NPMS would also reinforce operators' efforts in developing and 
maintaining adequate maps and records of their systems.
---------------------------------------------------------------------------

    \267\ PHMSA acknowledges that stakeholders do not have uniform 
access to information within NPMS.
---------------------------------------------------------------------------

    In addition to the benefits detailed above, PHMSA expects that its 
proposed amendments to NPMS requirements may also improve operators' 
leak detection programs. First, it would ensure that operators know the 
location of their pipelines; accurate location information can improve 
the accuracy of leakage surveys and patrols for buried pipelines, 
especially for leakage surveys performed with handheld equipment. 
Second, if a pipeline is in the NPMS, it is easier for third parties 
such as other operators, researchers, or the public to report leaks, 
ruptures, and other unsafe conditions to the operator. Public interest 
groups and aerial survey technology providers have noted that they have 
had difficulty identifying the operator of a facility where a leak 
indication was detected. PHMSA solicits comment on whether, within a 
final rule in this proceeding, it would be appropriate to require NPMS 
participation for Type R gathering pipelines not regulated under part 
192. Comments on this question are especially helpful if they address 
the potential safety and environmental benefits and potential costs of 
that particular approach, including whether that approach would be 
technically feasible, cost-effective, and practicable.
    While operators may engage third parties as part of their efforts 
to comply with the requirements proposed herein (for example, by 
contracting with vendors of technologies such as those discussed in 
section II.D.4 above), PHMSA has not proposed in this NPRM any formal 
role for third parties in the detection or reporting of leaks or 
intentional emissions. PHMSA invites comment on whether PHMSA should 
revise Sec.  192.605 to address operators' procedures for responding to 
third-party reports of gas releases or otherwise incorporate elements 
from or leverage EPA's super-emitter response program proposed in the 
EPA SNPRM for third party leak reporting \268\ as a backstop to support 
the reporting requirements proposed herein (for potential inclusion 
within a final rule in this proceeding), including whether data from 
such third party leak reporting should be included in operator reports 
to PHMSA (including aggregate emissions estimates by grade). PHMSA 
further invites comment on whether to facilitate third party reporting 
of operator non-compliance with the proposed requirements in this 
rulemaking (or any other provision of PHMSA regulations) to the 
attention of PHMSA enforcement personnel or State partners. Comments on 
these questions are especially helpful to PHMSA when they identify 
specific proposals supported by research or operational experience, 
along with the potential safety and environmental benefits and 
potential costs of a particular approach (including whether that 
approach would be technically feasible, cost-effective, and 
practicable).
---------------------------------------------------------------------------

    \268\ See EPA SNPRM, 87 FR at 74746.
---------------------------------------------------------------------------

    PHMSA understands that the proposed enhanced reporting and NPMS 
requirements discussed above would be reasonable, technically feasible, 
cost-effective, and practicable for affected gas pipeline operators. 
The contents of PHMSA's proposed new large-volume gas release report 
will resemble longstanding incident reporting requirements applicable 
to unintentional releases from part 192-regulated gas pipelines. 
Meanwhile, PHMSA's proposed enhanced annual reporting requirements for 
leak and repair activity would largely consist of reporting of 
information obtained from operator efforts in complying with the 
enhanced leak detection and repair requirements proposed elsewhere in 
this NPRM. Meanwhile, PHMSA's proposal to extend NPMS requirements to 
all part 192-regulated gas gathering lines would merely require those 
operators to submit information (including the precise location of 
their pipelines, the commodity transported, etc.) that reasonably 
prudent operators would maintain in ordinary course to protect public 
safety and the environment from the pressurized (natural flammable, 
corrosive, or toxic) gases transported in their pipelines. Viewed 
against those considerations and the compliance costs estimated in the 
Preliminary RIA, PHMSA expects its proposed amendments to part 191 
reporting requirements will be a cost-effective approach to obtaining 
enhanced data on intentional and unintentional releases of methane and 
other part 192-regulated gases necessary to inform PHMSA enforcement, 
policy development, and incident avoidance and response efforts. 
Lastly, the NPRM's proposed compliance timelines with those proposed 
reporting requirements--which are based on an effective date of six 
months after the publication date of a final rule in this proceeding 
(which would necessarily be in addition to the time since issuance of 
this NPRM)--would provide operators ample time to design and implement 
requisite protocols and manage any related compliance costs.

F. Mitigating Vented and Other Emissions From Gas Pipeline Facilities--
Sec. Sec.  192.9, 192.12, 192.605, 192.770, 193.2503, 193.2523 and 
193.2605

    In light of the significant methane emissions associated with 
blowdowns and other vented gas emissions from PHMSA-jurisdictional gas 
pipeline facilities, and to facilitate operator implementation of the 
self-executing mandate in section 114 of the PIPES Act of 2020, PHMSA 
proposes to incorporate that statutory language within the Pipeline 
Safety Regulations.\269\ Specifically, PHMSA proposes to incorporate an 
explicit requirement to eliminate leaks of all flammable, toxic, or 
corrosive gases, as well as minimize releases of natural gas, within 
provisions prescribing the content of operating, emergency, and 
maintenance manuals for gas transmission, distribution, Type A 
gathering and offshore gathering pipelines (Sec.  192.605 via current 
Sec.  192.9), Types B and C gathering pipelines (Sec.  192.605 via a 
revised Sec.  192.9(d) and (e)), UNGSFs (Sec.  191.12(c)), and part 193 
LNG facilities (Sec. Sec.  193.2503 and 193.2605). The proposed broad-
based incorporation of the PIPES Act of 2020 section 114 mandate would 
promote operator compliance efforts by aligning

[[Page 31948]]

PHMSA's regulatory requirements with the statutory mandate and helping 
to ensure that leak elimination and natural gas release mitigation 
inform the spectrum of operator activities. The proposed regulatory 
text would reinforce other operator obligations (including, but not 
limited to, repair criteria and IM requirements) throughout PHMSA 
regulations that improve safety, environmental protection, and U.S. 
competitiveness.
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    \269\ PHMSA has, pursuant to section 114 of the PIPES Act of 
2020, initiated a study on the best available technology or 
practices to reduce methane emissions associated with design, 
construction, operations, and maintenance of pipeline facilities, 
and will initiate a rulemaking based on the results of that study.
---------------------------------------------------------------------------

    PHMSA proposes that operators of gas transmission, offshore 
gathering, Type A gathering, and part 193 LNG facilities would have to 
adopt specific requirements for minimizing the release of gas during 
non-emergency blowdowns, LNG tank boil-offs, and other vented emissions 
events. According to GHGI data described in section II.C of this NPRM, 
approximately one-fourth of annual methane emissions from U.S. natural 
gas transmission pipelines are from vented emissions, including 
blowdowns. For LNG facilities, blowdowns represented around 48% of 
methane emissions, and as much as 80% of methane emissions from storage 
appurtenant to LNG facilities. PHMSA also notes that boil-offs of LNG 
storage tanks at part 193 LNG facilities to accommodate maintenance 
activity are similar in function to blowdowns on part 192 pipeline 
facilities--and similarly can be significant contributors of methane 
emissions if released to atmosphere.\270\ Mitigation of non-emergency 
vented emissions as an important opportunity for reducing methane 
emissions. The EPA Natural Gas STAR program listed blowdown volume 
mitigation among several cost-effective and recommended technologies 
for reducing methane emissions from operations, maintenance, and 
construction.\271\Additionally, the ``Best Management Practice'' 
commitment option for EPA's voluntary Methane Challenge program 
identifies various methods of reducing or eliminating blowdown 
emissions volumes similar to those proposed in this NPRM.\272\ The PST 
has identified similar mitigation options in public comments to 
rulemaking actions dating from 2016, and INGAA included minimizing 
blowdown volume in a list of commitments that member companies are 
making to address methane emissions.\273\
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    \270\ Vented and other releases of cryogenic LNG to the 
atmosphere also present unique safety hazards and can cause 
flammable vapor clouds, jet or pool fires in the presence of an 
ignition source, or a sudden and explosive phase change if LNG 
encounters a warm surface such as water. When spilled directly onto 
water, LNG can rapidly convert from liquid to gaseous phase, 
releasing enough energy to cause a physical explosion without any 
combustion or chemical reaction. See World Bank Group, 
Environmental, Health, and Safety Guidelines: Liquefied Natural Gas 
Facilities (2017). In addition, vented releases of unprocessed gas 
results in the release of VOCs and HAPs that entail distinguishable 
environmental and public safety harms.
    \271\ See PRO Fact Sheets Nos. 401, https://www.epa.gov/sites/default/files/2016-06/documents/injectblowdowngas.pdf.
    \272\ EPA, ``Natural Gas STAR Methane Challenge Program: BPM 
Commitment Option Technical Document'' (May 2022), https://www.epa.gov/system/files/documents/2022-05/MC_BMP_TechnicalDocument_2022-05.pdf (last accessed Dec. 20, 2022).
    \273\ https://www.ingaa.org/File.aspx?id=38582; https://www.regulations.gov/comment/PHMSA-2011-0023-0272.
---------------------------------------------------------------------------

    PHMSA therefore proposes to amend its regulations pertaining to 
each of gas transmission, regulated offshore gathering, and Type A 
gathering pipelines (Sec.  192.770) and part 193 LNG facilities (Sec.  
193.2523) to identify a menu of proven options--many of them featuring 
prominently in the voluntary initiatives described in the preceding 
paragraph that operators must choose from to mitigate methane releases 
during blowdowns, tank boil-offs, and other vented emissions.
    Proposed Sec. Sec.  192.770(a) and 193.2523(a) include an option to 
install and use valves or control fittings to reduce the volume of gas 
that must be removed from pipeline facility segments. Instead of 
blowing down a pipeline facility between mainline block valves or 
compressor stations, the operator would isolate a shorter segment of 
pipe, resulting in lower release volumes. In addition to the emissions 
abatement benefits from isolating shorter segments for maintenance 
tasks, this approach can have operational benefits from reducing or 
eliminating downtime by bypassing the shut-in segment. A second 
proposed method is routing vented gas to a flare stack to be ignited or 
to other equipment to be collected for later use. Burning gas rather 
than releasing it into the atmosphere significantly reduces the climate 
change impacts of vented emissions by converting methane gas to carbon 
dioxide and water via combustion. Under favorable conditions a well-
designed and maintained flare stack can combust gas with almost 100% 
efficiency, however leaks and unlit or incomplete flaring (due to poor 
maintenance, design, or operation practices) can reduce the methane 
reduction efficiency on a field-level basis to approximately 90%.\274\ 
Leaks and releases from flaring equipment would be subject to the 
proposed amendments in this NPRM as components of a ``pipeline'' as 
defined in parts 191 and 192. Routing or recovering gas for use as a 
fuel source is similar in principle to flaring. The third, fourth, and 
fifth approaches identified in proposed Sec. Sec.  192.770(a) and 
193.2523 involve reducing pressure (or, in the case of LNG tank boil-
off, LNG volumes) of a pipeline segment prior to venting, thereby 
reducing total emissions volume. In the third approach, an operator 
would isolate the pipeline segment upstream of the vented segment and 
use the downstream compressor station to reduce the pressure of the 
affected segment. The fourth approach is similar except instead of the 
compressor station, an operator would use a mobile compressor unit to 
reduce the pressure of the segment by compressing gas, or diverting 
LNG, into adjacent facilities or a storage vessel. The fifth approach--
transferring gas or LNG to a lower-pressure pipeline segment--is like 
the fourth, except it may be performed without compression in certain 
circumstances. PHMSA seeks comment on whether it is appropriate to 
specify a minimum pressure or pressure reduction in the vented segment 
for pressure reduction methods and any other mitigation measures 
operators should consider. Lastly, PHMSA proposes that operators be 
able to employ alternative approaches not listed in Sec. Sec.  
192.770(a) and 193.2523(a) for release volume mitigation, provided that 
the operator can demonstrate that a proposed approach reduces the 
volume of released gas by at least 50% compared with taking no 
mitigative action. This is consistent with the approach used in the 
EPA's Methane Challenge \275\ program and would provide operators with 
flexibility to employ techniques and technologies appropriate for the 
unique operating and environmental conditions of their facilities and 
would accommodate future advancements in release mitigation 
technologies and practices. PHMSA invites comment on whether, for any 
(or all) of the release volume mitigation approaches proposed in 
Sec. Sec.  192.770(a)(1) through (5) and 193.2523(a)(1) through (3), 
operators should be required to demonstrate that a particular approach 
reduces the

[[Page 31949]]

volume of released gas by at least 50% compared with taking no action 
(consistent with the EPA's Methane Challenge program) (for potential 
inclusion within a final rule in this proceeding). PHMSA further 
invites comment on whether a different minimum percentage reduction 
(higher or lower than 50%) would instead be more appropriate for any 
(or all) of the release volume mitigation approaches proposed in 
Sec. Sec.  192.770(a) and 193.2523(a) (for potential inclusion within a 
final rule in this proceeding). Comments on each of these questions are 
especially helpful when they are supported by research or operational 
experience, along with the potential safety and environmental benefits 
and potential costs of a particular approach (including whether that 
approach would be technically feasible, cost-effective, and 
practicable).
---------------------------------------------------------------------------

    \274\ Duren, Riley and Deborah Gordon. ``Tackling unlit and 
inefficient gas flaring,'' Science. Vol. 337 Issue 6614. (2022): 
1486-1487. https://www.science.org/doi/full/10.1126/science.ade2315.
    \275\ See EPA, ``Methane Challenge Program BMP Commitment Option 
Technical Document'' at pg. 21 (May 2022), https://www.epa.gov/system/files/documents/2022-05/MC_BMP_TechnicalDocument_2022-05.pdf 
(last accessed March 16, 2023).
---------------------------------------------------------------------------

    PHMSA further proposes in Sec. Sec.  192.770(c) and 193.2523(c) 
that those operators develop documentation describing the suite of 
actions undertaken--including, but not limited to, their choice from 
among the blowdown mitigation method(s) identified in either Sec. Sec.  
192.770(a) or 193.2523(a)--to minimize vented emissions from their 
systems. PHMSA does not propose to require mitigation for emergency 
blowdowns pursuant to an emergency plan under Sec. Sec.  192.615(a)(3) 
or 193.2509 so as to ensure that emissions mitigation will not come at 
the expense of public safety and other environmental resources; 
however, PHMSA proposes at Sec. Sec.  192.770(b) and 193.2523(b) to 
require that operators document such events, including the 
justification for not taking mitigative action.\276\
---------------------------------------------------------------------------

    \276\ Note that a blowdown that is not mitigated may also be 
reportable under the proposed large-volume gas release report.
---------------------------------------------------------------------------

    PHMSA understands that its proposed requirements for minimizing 
vented and other releases from certain gas pipeline facilities 
discussed above would be reasonable, technically feasible, cost-
effective, and practicable for affected gas pipeline operators. PHMSA 
understands that some affected operators may already have adopted 
protocols for minimizing vented emissions and eliminating leaks from 
their facilities either voluntarily (e.g., to minimize loss of a 
commercially valuable--and hazardous--commodity) or in response to 
State or Federal requirements (including, but not limited to, the self-
executing mandate in section 114 of the PIPES Act of 2020). The NPRM 
reinforces those efforts by codifying that self-executing statutory 
mandate in the pipeline safety regulations. Similarly, PHMSA's 
proposals accommodate a variety of compliance strategies; the text of 
pertinent regulatory provisions contains a non-exclusive menu of 
compliant approaches from which operators can choose as appropriate for 
their needs and their facilities' operational characteristics and 
environment. Viewed against those considerations and the compliance 
costs estimated in the Preliminary RIA, PHMSA expects its proposed 
amendments will be a cost-effective approach to achieving the 
commercial, public safety, and environmental benefits discussed in this 
NPRM and its supporting documents. Lastly, the NPRM's proposed 
compliance timelines--which are based on an effective date of six 
months after the publication date of a final rule in this proceeding 
(which would necessarily be in addition to the time since issuance of 
this NPRM)--would provide operators ample time to develop and implement 
compliance protocols and manage any related compliance costs.
    Although the NPRM does not include a similar prescribed menu of 
required blowdown emissions mitigation approaches for gas distribution 
or Types B and C gathering pipelines due to the comparatively smaller 
blowdown volumes of some of those systems, PHMSA seeks comment on 
whether, within a final rule in this proceeding, it would be 
appropriate to require use of some of the methods for mitigating 
transmission pipeline and LNG facility blowdown emissions proposed 
herein for use on gas distribution or Types B and C gathering 
pipelines. PHMSA also seeks comment on whether it is appropriate to 
restrict the use of flaring to instances where other mitigation 
measures are impracticable. Comments on these questions are especially 
helpful if they address the potential safety and environmental benefits 
and potential costs of a particular approach, including whether that 
approach would be technically feasible, cost-effective, and 
practicable.
    The proposals described in this section are intended to codify 
section 114(a) and (b) of the PIPES Act of 2020 and address a subset of 
operations and maintenance-related emissions sources. PHMSA has a 
separate Congressional mandate under section 114(d) of the PIPES Act of 
2020 to promulgate pipeline design, operations, and maintenance 
requirements to ``prevent or minimize, without compromising pipeline 
safety, the release of natural gas'' in connection with intentional 
operator releases. PHMSA will address this mandate in a future 
rulemaking action following the completion of a report to Congress 
discussing the best available technologies, practices, and designs to 
prevent or minimize such releases (per section 114(d)(1) of the PIPES 
Act of 2020).\277\ Specifically, the report must evaluate pipeline 
facility designs that mitigate the need to intentionally vent natural 
gas (without compromising pipeline safety) as well as the best 
available technologies or practices to prevent or minimize (without 
compromising pipeline safety) the release of natural gas when making 
planned repairs, replacements, or maintenance to a pipeline facility 
and when the operator intentionally vents or releases natural gas, 
including blowdowns. As of the date of issuance of this final rule, 
PHMSA is in the process of developing the best available technologies 
and practices report referenced in section 114(d)(1).
---------------------------------------------------------------------------

    \277\ Section 114(d)(2) of the PIPES Act of 2020 requires the 
Secretary to update the Pipeline Safety Regulations that the 
Secretary has determined are necessary to protect the environment 
without compromising safety within 180 days after submitting the 
section 114(d)(1) report.
---------------------------------------------------------------------------

G. Design, Configuration, and Maintenance of Pressure Relief Devices--
Sec. Sec.  192.9, 192.199 and 192.773

    PHMSA proposes to minimize emissions caused by malfunctioning 
pressure relief devices and other unnecessary releases from poorly 
designed or configured pressure relief devices. A pressure relief 
device vents gas to the atmosphere (or to a flare) when the pressure in 
the system satisfies either design or configuration actuation 
criteria,\278\ to protect the integrity of the facility from an 
overpressure condition. A pressure relief device may malfunction by not 
releasing gas as required by those criteria, risking an overpressure 
condition that can induce a loss of system integrity and release of gas 
to atmosphere. Alternatively, a pressure relief may malfunction by 
operating before those criteria have been satisfied, which results in 
unnecessary releases of gas to the atmosphere. Similarly, a pressure 
relief device with design or configuration actuation criteria more 
conservative than necessary to provide

[[Page 31950]]

adequate margin to an overpressure condition can also result in 
unnecessary gas releases. Additionally, a pressure relief device whose 
design or materials are ill-suited for use in a pipeline facility's 
particular operating and environmental conditions may fail or leak.
---------------------------------------------------------------------------

    \278\ PHMSA here draws a distinction between design actuation 
criteria set by a device manufacturer (which generally cannot be 
changed by an operator) and configuration actuation criteria (which 
in some cases could be changed by an operator post-manufacture and 
installation). PHMSA further notes that by ``actuation criteria'' it 
means the suite of setpoints (e.g., pressure) and other conditions 
(e.g., programmable logic) that must be satisfied for a pressure 
relief device to actuate and cease actuation. For example, actuation 
criteria may consist of a pressure setpoint at which a pressure 
relief valve may open, as well as a setpoint for that same valve to 
close.
---------------------------------------------------------------------------

    PHMSA often receives reports of major releases from pressure relief 
device failures: since 2010, operators have submitted 112 incident 
reports for releases from pressure relief devices on gas transmission 
and regulated gas gathering pipelines from 2010 through the end of 
2022, reporting an average release volume of 12.5 MMCF from each event. 
The largest relief device failure reported to PHMSA occurred on 
November 22, 2014, when an 8-inch relief valve on a 34-inch gas 
transmission pipeline operated by Pacific Gas and Electric (PG&E) 
malfunctioned, which released 119 MMCF of natural gas into the 
atmosphere until operating personnel were able to bypass the valve. 
Following the incident, PG&E contractors performed a root cause 
analysis and made unspecified changes to the pressure limiting station 
pending a future redesign.\279\
---------------------------------------------------------------------------

    \279\ PHMSA, ``Pipeline Incident Flagged Files'', https://www.phmsa.dot.gov/data-and-statistics/pipeline/pipeline-incident-flagged-files (last accessed Dec. 20, 2022) (memorialized within 
Report ID No. 20140148).
---------------------------------------------------------------------------

    Out of these incident reports 84 were caused by a malfunction of 
the relief device or other pressure control equipment.

   Gas Transmission and Regulated Gas Gathering Pressure Relief Device
                                Incidents
------------------------------------------------------------------------
                                                          Incidents 2010-
              Primary cause and  sub-cause                     2022
------------------------------------------------------------------------
Equipment failure: malfunction of control/relief                      84
 equipment..............................................
Equipment failure: other equipment failure..............               5
Equipment failure: threaded connection/coupling failure.               2
Equipment failure: defective of loose tubing/fitting....               1
Incorrect operation: other incorrect operation..........               8
Incorrect operation: pipeline/equipment over pressurized               3
Incorrect operation: incorrect valve position...........               2
Incorrect operation: incorrect equipment................               1
Natural force damage: temperature.......................               4
Miscellaneous...........................................               2
                                                         ---------------
    Total...............................................             112
------------------------------------------------------------------------

    The most common causes of these failures according to narratives in 
part G6 or H of operator's gas transmission incident reports are 
mechanical failures of the relief device, including failures to reseat 
or reseal after activation, and failures caused when liquid 
contaminants cause a relief device to freeze open or closed in cold 
weather conditions. Other reported incidents have resulted from the use 
of pressure relief devices whose design and material were inappropriate 
for the pipelines on which they were installed and expected operating 
conditions. For example, incidents were attributed to improper 
calibration, design issue with the location of the sensing line, 
pressure programming or setting issues, improper setpoint, 
construction, or programming issues, an oversized or undersized 
pressure relief device and inlet piping, high pipeline flow conditions, 
and setpoint drift.
    Other data sources suggest these incident report figures may 
undercount relief device emissions that could be prevented through 
better design, configuration, and maintenance. For example, PHMSA 
receives inquiries from media sources based on satellite documentation 
of significant methane releases. Additionally, PHMSA is notified of 
National Response Center reports on releases involving pressure relief 
devices in accordance with Sec.  191.5 approximately once a week, with 
39 NRC reports referencing relief valves in the description in calendar 
year 2021.\280\ Operators report such releases to the National Response 
Center more frequently than they file incident reports pursuant to 
Sec. Sec.  191.9 or 191.15, which suggests that operators may--after 
reporting them to the National Response Center immediately after 
discovery of a release--subsequently designate some emissions from 
relief devices as ``intentional'' emissions that are not required to be 
reported to PHMSA as incidents.\281\
---------------------------------------------------------------------------

    \280\ United States Coast Guard, National Response Center, 
https://nrc.uscg.mil/ (last accessed Dec. 20, 2022).
    \281\ The discrepancy between events reported to the National 
Response Center pursuant to Sec.  191.5 and those ultimately 
reported as incidents pursuant to Sec. Sec.  191.9 or 191.15 
reflects a difference in timing between these two reporting 
requirements: the Sec.  191.5 reporting requirement obliges 
operators to notify the National Response Center at ``the earliest 
practicable'' moment--which in practice can mean before a formal 
decision has been made by the operator to designate an event as an 
``incident'' reported to PHMSA some time (as many as 30 days later) 
pursuant to Sec. Sec.  191.9 or 191.15.
---------------------------------------------------------------------------

    Overpressurization is a critical safety issue and can result in a 
pipeline incident or rupture with grave public safety and environmental 
consequences. However, inadequate design and configuration of pressure 
relief devices may result in potentially very large releases beyond 
that necessary to provide overpressure protection. Additionally, relief 
device malfunctions due to inadequate maintenance or other issues can 
result in a failure to provide reliable overpressure protection if it 
fails to operate or significant emissions if the device leaks or 
operates unintentionally. PHMSA has observed through inspections and 
other regulatory oversight activities, that operator procedures, 
including the choice of design and configuration actuation criteria, 
may not be optimized to reduce emissions associated with pressure 
relief device malfunctions or operations beyond what is necessary to 
provide overpressure protection. For example, some operators take an 
overly conservative approach to avoiding overpressure conditions and 
employ design and configuration actuation criteria such that those 
pressure relief valves will release gas to the atmosphere either more 
frequently or in greater quantities than necessary to protect against 
an overpressure condition.
    PHMSA proposes to revise Sec.  192.199 to require operators of all 
new and replaced, relocated, or otherwise changed gas transmission, 
distribution, and part 192-regulated gathering pipelines be designed 
and configured, as demonstrated by documented engineering analysis, to 
minimize unnecessary releases of gas. Section 192.199 would prescribe a 
series of elements that operators must demonstrate would minimize 
emissions using engineering analysis. These elements include the choice 
of design material and function, configuration actuation conditions, 
pressure relief device piping characteristics, presence of isolation 
valves to facilitate testing and maintenance, and compatibility of 
material and design with use. In addition, PHMSA proposes a new Sec.  
192.773 that, coupled with proposed revisions to Sec.  192.9, would 
require operators of all gas transmission, distribution, and part 192-
regulated gathering pipelines to develop procedures to assess the 
proper function of pressure relief devices on their facilities and 
remediate or replace any

[[Page 31951]]

malfunctioning devices. This change ensures that operator's maintenance 
procedures ensure reliable overpressure protection and the minimization 
of emission from malfunctioning pressure relief devices. PHMSA's 
proposed language also identifies specific action operators would have 
to take on operation of a malfunctioning pressure relief device. PHMSA 
proposes to require a relief device be repaired or replaced immediately 
if it operates above the pressure limits in Sec.  192.201(a) or Sec.  
192.739, fails to operate, or otherwise fails to provide reliable 
overpressure protection due to the potential consequences of 
overpressurizing the pipeline.
    On the other hand, a relief device that activates below the 
intended set pressure poses a hazard to the environment, especially if 
it releases gas at normal operating pressure. Therefore, PHMSA also 
proposes that if a relief device activates below the set pressure 
range, the operator must take immediate and continuous action to stop 
the release of gas and ensure operation with an adequate margin to 
overpressure conditions. The device must then be repaired or replaced 
as soon as practicable, and within 30 days. Action to stop the flow of 
gas should be defined in an operator's abnormal operating procedures 
and could include reconfiguring the relief device.
    In either case the operators would be obliged to maintain records 
documenting the proper operation and any remediation/replacement of 
pressure relief devices for the service life of their facilities.
    PHMSA understands that its proposed requirements for design, 
configuration, and maintenance of pressure relief valves discussed 
above would be reasonable, technically feasible, cost-effective, and 
practicable for affected gas pipeline operators. PHMSA understands that 
some affected operators may already have adopted protocols ensuring 
that the design and configuration of pressure relief devices minimizes 
emissions of pressurized (natural, toxic, corrosive, or flammable) 
gases, either voluntarily (to minimize loss of commercially valuable 
commodities) or in response to State or Federal requirements. The NPRM 
would backstop those existing practices by enshrining them in 
regulation by prescribing release mitigation as a mandatory factor in 
the design and selection of new pressure relief devices; the NPRM 
contemplates operators would have flexibility within that broad 
objective to develop their precise implementation strategy for a 
particular (new) pressure relief device. Similarly, existing pressure 
relief device configurations would need to be tweaked to minimize 
releases as well, but only so far as such configurations can be 
changed; operators whose pressure relief devices do not admit changes 
in configuration would not have to effectuate any changes. Viewed 
against those considerations and the compliance costs estimated in the 
Preliminary RIA, PHMSA expects its proposed amendments will be a cost-
effective approach to achieving the commercial, public safety, and 
environmental benefits discussed in this NPRM and its supporting 
documents. Lastly, the NPRM's proposed compliance timelines--which are 
based on an effective date of six months after the publication date of 
a final rule in this proceeding (which would necessarily be in addition 
to the time since issuance of this NPRM)--would provide operators ample 
time to develop and implement compliance protocols and manage any 
related compliance costs.

H. Investigation of Failures--Sec.  192.617

    Understanding the causes of pipeline leaks and reasons for 
malfunction of pressure relief devices is essential for identifying 
systemic threats to pipeline integrity and preventing similar failures 
in the future. Although PHMSA regulations at Sec.  192.617 require 
operators of gas distribution, transmission, offshore gathering, and 
Type A gathering pipelines to have procedures for analyzing the causes 
of ``failures and incidents,'' \282\ those requirements are limited in 
application (they do not apply to Types B and C gathering pipelines), 
and ``failure'' is not defined in part 192. With respect to the meaning 
of the term ``failure'', operators have applied the definition in the 
instructions for the Gas Transmission and Gas Gathering Pipeline System 
Annual Report,\283\ which references the broad, functional definition 
in ASME B31.8, ``Gas Transmission and Distribution Piping Systems.'' 
ASME B31.8 defines a failure as the following:
---------------------------------------------------------------------------

    \282\ PHMSA's discussion of Sec.  192.617 describes the text of 
that provision as it will be amended on the October 5, 2022, 
effective date of the Valve Installation and Rupture Detection Final 
Rule.
    \283\ PHMSA Form F 7100.2-1 (revision 10-2021), Instruction 
Revision (10-2021). https://www.phmsa.dot.gov/sites/phmsa.dot.gov/files/2021-10/Current%20GT%20GG%20Annual%20Instructions%20-%20PHMSA%20F%207100%202-1%20Approved%2010-2021%20for%20CY%202021%20and%20Beyond.pdf.

    failure: a general term used to imply that a part in service has 
become completely inoperable; is still operable but is incapable of 
satisfactorily performing its intended function; or has deteriorated 
seriously, to the point that it has become unreliable or unsafe for 
---------------------------------------------------------------------------
continued use.

    Although PHMSA has issued interpretations suggesting that leaks 
caused by certain mechanisms (in particular, those resulting from 
corrosion) would require investigation pursuant to Sec.  192.617,\284\ 
PHMSA regulations do not require investigation of all failures that 
result in leaks. This limitation could prevent investigations that can 
identify systemic integrity threats to their pipelines--as well as 
denies PHMSA and State regulators information necessary to protect 
public safety and the environment.
---------------------------------------------------------------------------

    \284\ PHMSA, Interpretation Response Letter No. PI-92-033 (Jul. 
16, 1992).
---------------------------------------------------------------------------

    PHMSA therefore proposes to address the lack of specificity of the 
definition of a failure by revising Sec.  192.617 to define the term 
``failure'' for the purposes of that section using language similar to 
that in ASME B31.8. This approach would facilitate compliance by 
leveraging elements of a consensus industry standard with which 
operators are familiar, and portions of which are incorporated by 
reference elsewhere in PHMSA regulations. Additionally, PHMSA already 
references ASME B31.8's functional definition of a failure in the 
instructions for gas transmission and regulated gathering pipeline 
annual reports. Since a leaking pipe has failed to contain gas, a 
failure that results in a leak would be required to be investigated in 
accordance with Sec.  192.617. The proposed definition clarifying that 
all leaks on pertinent gas pipelines require investigation under Sec.  
192.617 would improve safety. The proposed changes are intended to 
complement the leak grading and repair requirements in this NPRM (as 
well as repair criteria and IM requirements elsewhere in PHMSA 
regulations) and equip operators, PHMSA, and State regulators with the 
information needed in developing proactive initiatives to avoid future 
pipeline failures. Viewed against those considerations and the 
compliance costs estimated in the Preliminary RIA, PHMSA expects this 
proposed amendment will be a cost-effective approach to achieving the 
commercial, public safety, and environmental benefits discussed in this 
NPRM and its supporting documents. Lastly, the NPRM's proposed 
compliance timelines--which are based on an effective date of six 
months after the publication date of a final rule in this proceeding 
(which would necessarily be in addition to the time since issuance of 
this NPRM)--would provide operators ample time to develop

[[Page 31952]]

and implement compliance protocols and manage any related compliance 
costs.
    Although PHMSA proposes to limit the scope of application of this 
revised definition of ``failure'' to Sec.  192.617, it acknowledges 
that term is used elsewhere in PHMSA regulations. PHMSA therefore 
invites comment on whether the proposed definition of ``failure'' 
should instead be located within the broadly applicable definitions at 
Sec.  192.3 (for potential inclusion within a final rule in this 
proceeding). Comments on this question are especially helpful if they 
address the potential safety and environmental benefits and potential 
costs of that approach, including whether that approach would be 
technically feasible, cost-effective, and practicable.

I. Type B and Type C Gathering Pipelines--Sec.  192.9

    Types B and C gathering pipelines are not currently subject to all 
of the part 192 safety requirements broadly applicable to other part 
192-regulated gas pipelines, including those pertaining to procedural 
manuals for operations, maintenance, and emergency response procedures 
(Sec.  192.605), patrolling (Sec.  192.705), and certain recordkeeping 
(Sec.  192.709); Type B gathering pipelines are also not subject to 
emergency planning requirements set forth in Sec.  192.615. Further, 
because Types B and C gathering pipelines are not subject to Sec.  
192.605, some stakeholders have questioned whether those pipelines are 
excepted from the self-executing requirements within section 114 of the 
PIPES Act of 2020 for operators to have procedures to eliminate leaks, 
minimize releases of natural gas, and repair or remediate pipelines 
known to leak.\285\ Additionally, most Type C gathering pipelines are, 
pursuant to Sec.  192.9(f)(1), not even subject to PHMSA's minimal 
existing requirements for leakage surveys (Sec.  192.706) and repair of 
hazardous leaks (Sec.  192.703(c)).\286\
---------------------------------------------------------------------------

    \285\ See, e.g., GPA Midstream and American Petroleum Institute, 
``Joint Comments re Docket No. PHMSA-2021-0039, Pipeline Leak 
Detection, Leak Repair and Methane Emission Reductions Public 
Meeting'' at 4-5 (May 24, 2021).
    \286\ PHMSA's RIA for the Gas Gathering Final Rule estimated 
only ca. 20,000 miles (of the ca. 90,000 total miles of Type C 
pipelines) would be subject to Sec. Sec.  192.703 and 192.705. See 
Gas Gathering RIA at 15.
---------------------------------------------------------------------------

    These limitations contribute to public safety and environmental 
risks. PHMSA has historically imposed each of the requirements listed 
in the preceding paragraph on gas transmission and Type A gathering 
pipelines precisely because of the self-evident, appreciable public 
safety benefits they entail.\287\ Although PHMSA previously declined to 
extend those minimal requirements to Types B and C gathering pipelines 
(representing the majority of part 192-regulated gathering pipeline 
mileage),\288\ the notable public safety and environmental risks from 
Types B and C gathering pipelines discussed throughout this NPRM 
warrant removal of those historic regulatory gaps. As described above 
in section II.C.2, incidents and leaks occur on Type B and Type C 
gathering pipelines just as they occur on Type A pipelines. For Type B 
lines, the public safety risks of any incident are evident due to the 
location of those pipelines in densely-populated Class 2, 3 and 4 
locations, while the high operating pressures and large diameters of 
Type C pipelines entail risks to public safety similar to those posed 
by Type A pipelines (notwithstanding Type C lines' location in more 
sparsely-populated Class 1 areas than Type A lines).\289\ And as 
explained above, leaks from any type of natural gas gathering pipeline 
contains VOCs and HAPs, exacerbating public safety and environmental 
risk. Leaks of unprocessed natural gas also contain corrosive materials 
that can accelerate leak degradation.\290\ The public safety and 
environmental risks associated with releases (whether leaks or more 
serious incidents) from gas gathering pipelines also support extension 
of emergency planning requirements to Type B gas gathering pipelines, 
which are located in the vicinity of buildings intended for human 
occupancy; the emergency planning requirements at Sec.  192.615 will 
ensure that those operators have in place a robust framework for 
proactive measures to mitigate the public consequences of any emergency 
on their systems. Lastly, increasing appreciation for the outsized 
contribution to climate change of fugitive and vented emissions from 
all natural gas gathering pipelines underscores the importance of 
minimizing those greenhouse emissions from Types B and C regulated 
gathering pipelines.
---------------------------------------------------------------------------

    \287\ PHMSA, ``Gas Gathering Line Definition; Alternative 
Definition for Onshore Lines and New Safety Standards,'' 71 FR 
13289, 13292 (Mar. 15, 2006).
    \288\ See Gas Gathering RIA at 15 (noting a total of ca. 90,000 
miles of Type C gathering pipelines) and 30 (noting a total of ca. 
11,000 miles of Types A and B gathering pipelines).
    \289\ See Gas Gathering Final Rule at 63267.
    \290\ Leaks from part 192-regulated gathering lines transporting 
flammable, toxic, or corrosive gases other than natural gas also 
entail their own safety and environmental risks.
---------------------------------------------------------------------------

    This NPRM therefore proposes a series of regulatory amendments 
representing a first step in mitigating the anomalous treatment of 
Types B and C gathering pipelines in PHMSA regulations. Specifically, 
PHMSA proposes to revise Sec.  192.9 to add to the list of part 192 
requirements applicable to Types B and C pipelines each of its proposed 
requirements for pressure relief device design and maintenance 
(Sec. Sec.  192.199 and 192.773),\291\ certain recordkeeping (Sec.  
192.709) and procedural manual requirements for operations, 
maintenance, and emergency response (Sec.  192.605), and--for Type B 
gathering pipelines--the emergency planning requirements at Sec.  
192.615. Each of these requirements have proven utility in minimizing 
public safety and environmental risks from gas transmission and Type A 
gathering pipelines and exemplify common-sense programmatic elements 
that any responsible business owning facilities known to transport 
pressurized, hazardous commodities would maintain in ordinary course 
(even in the absence of explicit regulatory requirements) to protect 
public safety and the environment. Extension of the procedural manual 
requirements at Sec.  192.605 and recordkeeping requirements at Sec.  
192.709, moreover, would facilitate regulatory oversight of Types B and 
C gathering facilities by PHMSA and State inspectors by aligning 
documentation requirements with existing substantive requirements under 
Sec.  192.9. It would also dispel any uncertainty among stakeholders 
regarding application to Types B and C gathering pipelines of the self-
executing obligations under section 114 of the PIPES Act of 2020 to 
eliminate leaks, minimize emissions, and repair or remediate pipelines 
known to leak based on their material, design, or operating and 
maintenance history. Extension of the emergency planning requirements 
in Sec.  192.615 to Type B gathering pipelines would also improve 
public awareness of pipeline safety and emergency response to incidents 
on Type B gathering pipelines, bringing requirements for such pipelines 
in line with existing requirements for all other part 192-regulated gas 
pipelines. Effective emergency response requirements are critical to 
ensure the safety of the public, emergency responders, and operator 
personnel during gas pipeline emergencies on Type B gathering lines, 
which are located in Class 2, 3, and 4

[[Page 31953]]

locations.\292\ Section 192.615 includes requirements to ensure 
effective emergency preparedness, including a coordinated operator and 
community response to pipeline emergencies. Moreover, this requirement 
would ensure that operators of Type B gathering lines are prepared to 
take appropriate immediate and continuous actions in response to a 
grade 1 leak, which could require activation of an emergency response 
plan. PHMSA further proposes (as discussed above) to extend the suite 
of enhanced leak detection and repair-related proposals elsewhere in 
this NPRM to certain Types B and C gathering pipelines (including 
Sec. Sec.  192.703(c) and (d), 192.705, 192.706, 192.709, 192.760, 
192.763, and 192.769). Similarly, PHMSA also proposes to extend 
requirements for this NPRM's elements pressure relief device 
maintenance (Sec.  192.773) to Types B and C gathering pipelines to 
further reduce emissions and public safety and environmental risks 
associated with Types B and C gathering pipelines.
---------------------------------------------------------------------------

    \291\ As explained elsewhere, PHMSA's proposed Sec.  192.199 
requirements would only apply to new, replaced, relocated, or 
changed Type C gathering pipelines.
    \292\ Type B gathering pipelines are defined in Sec.  192.8 as 
those gathering pipelines located in Class 4, Class 3, and certain 
Class 2 locations with the operating characteristics specified in 
Table 1 to Sec.  192.8(c)(2).
---------------------------------------------------------------------------

    PHMSA expects the above proposed first steps toward improving 
alignment of regulatory requirements for Types B and C gas gathering 
pipelines with those applicable to other part 192-regulated pipelines 
would be reasonable, technically feasible, cost-effective, and 
practicable. The specific regulatory requirements PHMSA proposes to 
extend are common-sense, widely-employed approaches adopted by 
reasonably prudent operators in ordinary course to minimize losses of 
commercially valuable commodities and risks to public safety and the 
environment from the operation of pipelines transporting pressurized 
(natural, corrosive, toxic, or flammable) gases. Precisely for that 
reason, PHMSA expects that some Types B and C gas gathering pipeline 
operators may already voluntarily comply with those proposed 
requirements. Those and other operators of Types B and C gas gathering 
pipelines (some of which operators may also operate either gas 
transmission or Type A gathering pipelines) may also have pipelines 
within their systems subject to similar procedural manual, 
recordkeeping, and pressure relief device requirements under Federal or 
State law; those existing procedural manuals and (recordkeeping and 
pressure relief device design and configuration) protocols could be 
extended and adapted to Types B and C gas gathering pipelines. Viewed 
against those considerations and the compliance costs estimated in the 
Preliminary RIA, PHMSA expects its proposed amendments will be a cost-
effective approach to achieving the commercial, public safety, and 
environmental benefits discussed in this NPRM and its supporting 
documents. Lastly, the proposed compliance timelines--based on an 
effective date of the proposed requirements six months after the 
publication date of a final rule in this proceeding (which would 
necessarily be in addition to the time since issuance of this NPRM)--
would provide operators ample time to implement requisite changes to 
existing procedural manuals and protocols (and conduct any accompanying 
personnel training) and manage any related compliance costs.
    PHMSA solicits comment on additional opportunities to harmonize 
part 192 treatment of regulated gathering pipelines for potential 
inclusion within a final rule in this or a subsequent rulemaking 
proceeding. Comments on this question are especially helpful if they 
address the potential safety and environmental benefits and potential 
costs of a particular approach, including whether that approach would 
be technically feasible, cost-effective, and practicable.

J. Miscellaneous Changes in Parts 191 and 192 To Reflect Codification 
in Federal Regulation of the Congressional Mandate To Address 
Environmental Hazards of Leak From Gas Pipelines

    As discussed above in section II.D, current PHMSA regulations 
reflect an ambiguous distinction between ``hazardous'' and other leaks 
that reflects PHMSA's historical prioritization of public safety 
hazards. PHMSA's regulations at parts 191 and 192 consequently contain 
numerous references to ``potentially hazardous'' gas releases, or to 
``hazards'' expressed principally in terms of public safety risks. As 
discussed above in sections II.D.3, III.C.1, and III.C.6, all ``leaks'' 
are necessarily hazardous to the environment, and even a small leak can 
be hazardous to public safety, especially if it is allowed to continue 
indefinitely without repair and potentially degrade into a more serious 
leak or incident. PHMSA therefore proposes miscellaneous conforming 
revisions to various provisions of parts 191 and 192 consistent with 
the PIPES Act of 2020's direction. PHMSA proposes to define ``hazardous 
leak or leak'' in Sec.  192.3 and apply it to those subparts of part 
192 other than the IM regulations under subparts O and P. That proposed 
definition would make ``hazardous leak'' synonymous to ``leak.'' PHMSA 
also proposes to delete language in several places in part 192 
suggesting contingency (for example, references to ``potentially 
hazardous'' releases) at each of Sec. Sec.  192.503(a)(2), 192.507(a), 
192.509(a), 192.513(b), 192.553(a)(2), 192.557(b)(2), and 192.751(a)) 
regarding hazards posed by releases from gas pipelines.\293\ For other 
provisions (specifically, Sec. Sec.  192.605(b)(9), 192.613(b), 
192.615(a), 192.615(a) introduction, 192.616(d)(2) and (j)(2), and 
192.703(c)), existing language referring to ``hazard'' and ``hazardous 
leak'' is elastic enough to accommodate PHMSA's proposed expansion of 
the ``hazard'' concept to encompass environmental hazards without 
revision of regulatory text. Although the expansion of the ``hazard'' 
concept may require some operators to modify procedures and practices, 
PHMSA expects any compliance burdens would be de minimis because a 
reasonably prudent operator would employ practices and procedures 
addressing the need to minimize releases of natural gas and other 
environmental harms from their activities. In addition, the mechanism 
for public safety and environmental harms (the release of gas from a 
pipeline) is the same.
---------------------------------------------------------------------------

    \293\ PHMSA will also propose conforming revisions to the part 
191 annual report forms and instructions for each of gas 
transmission, offshore gathering and Types A, B, and C gathering 
pipelines (F7100.2-1), Type R gas gathering pipelines (F7100.2-3), 
and gas distribution pipelines (F7100.1-1) to eliminate distinctions 
made or suggested in those documents between hazardous leaks, other 
leaks, or other gas releases allegedly too small to merit reporting.
---------------------------------------------------------------------------

    This proposed expansion of ``hazardous leaks'' to encompass hazards 
to the environment and public safety could lead operators to modify 
testing practices. For example, PHMSA's proposed changes to subpart J 
testing requirements (specifically, Sec. Sec.  192.503(a)(2), 
192.507(a), 192.509(a), 192.513(b)) to limit placement into service of 
any new, replaced, relocated or otherwise changed gas transmission, 
distribution, offshore gathering, Types A, B, and C gathering pipeline 
segments with any leak could make testing and qualification of new, 
replaced, relocated, or changed pipelines more difficult in that it 
would require conforming revisions to operator acceptance criteria. 
However, PHMSA expects the impact of those proposed revisions would be 
de minimis, as reasonably prudent operators would not place new, 
replaced, relocated, or changed pipeline segments into service

[[Page 31954]]

if they had observed any leak during initial testing. The same logic 
would extend to its proposed amendment of uprating requirements (at 
Sec. Sec.  192.553(a)(2), 192.557(b)(2)) applicable to gas 
transmission, distribution, offshore gathering, and Type A gathering 
pipelines.
    PHMSA does not propose to expand every reference to ``hazard'' or 
``hazardous leak'' in PHMSA's part 191 and 192 regulations to encompass 
environmental hazards. First, PHMSA proposes to exclude the IM 
regulations at subparts O and P from application of the new definition 
of ``leak or hazardous leak'' at Sec.  192.3 to keep operator IM 
plans--and operators' limited resources implementing those plans--
focused on identification and management of public safety risks.\294\ 
PHMSA is proposing to revise Sec.  192.1007 to delete a reference to 
Sec.  192.703(c) that would be rendered obsolete by the limited 
application of PHMSA's proposed definition of ``leak or hazardous 
leak'' at Sec.  192.3. Second, PHMSA is not proposing to refer to 
``hazards'' or leaks ``hazardous to public safety'' where an explicit 
reference to environmental hazards would either be unnecessary (e.g., 
because other subparagraphs within the same provision would address any 
environmental hazards) or inapposite to the pertinent requirement. This 
applies to Sec. Sec.  192.605(c)(1)(v), 192.605(a)(6) and (7), 
192.615(c), and 192.721. Similarly, PHMSA proposes to revise other 
references to (unqualified) ``hazards'' to preserve those provisions' 
historical and appropriate focus on public safety, rather than 
environmental, hazards. Generally, those proposed regulatory amendments 
would consist of addition of qualifying language (``hazard(s) to public 
safety'') where an explicit reference to environmental hazards would 
either be unnecessary (e.g., because other, related provisions or 
paragraphs would address any environmental hazards) or inapposite to 
the pertinent requirement. PHMSA proposes these conforming amendments 
for Sec. Sec.  191.23(a)(9), 192.167(a)(2), 192.169(b), 192.179(c), 
192.199(e), 192.361(f)(3), 192.363(c), 192.629(a) and (b), 192.727(b) 
and (c) and 192.751. Third, even though PHMSA does not propose to 
expand the concept of ``hazard'' uniformly across its regulations, 
operators nevertheless may voluntarily supplement the baseline 
requirements of PHMSA regulations by explicitly incorporating 
environmental harms from releases of gas from their pipelines 
throughout their policies, procedures, and practices.
---------------------------------------------------------------------------

    \294\ Similarly, this proposed definition would not apply to IM 
programs for UNGSFs, which are not subject to any requirements of 
part 192 aside from Sec.  192.12(d).
---------------------------------------------------------------------------

    PHMSA expects no material impact on operators' existing practices 
from the above proposed new definition (along with the limited, 
conforming revisions specified above), which supports a conclusion that 
those proposed amendments would be reasonable, technically feasible, 
cost-effective, and practicable. PHMSA invites comment by stakeholders 
on the appropriateness of each of its above proposed revisions to, or 
preservation of, existing regulatory references to ``hazards'' and 
``hazardous leaks'' for potential modification of its above proposed 
amendments in any final rule issued in this proceeding. PHMSA also 
solicits comment on whether any provisions not addressed above would 
also benefit from conforming revision. Should stakeholders proffer 
alternative or additional regulatory amendments, they should support 
those proposals by reference to each of any expected safety and 
environmental benefits, as well as the cost-effectiveness, 
practicability, and technical feasibility.

V. Section-By-Section Analysis

Sec.  191.3 Definitions

    PHMSA proposes to revise Sec.  191.3 to add a definition for large-
volume gas releases that must be reported, per the new Sec.  191.19. 
PHMSA proposes to define a ``large-volume gas release'' as an 
intentional or unintentional release of gas of 1 MMCF or more. This new 
large-volume gas release reporting requirement would be applicable to 
all gas pipeline facility operators, including (but not limited to) 
operators of jurisdictional underground storage and LNG facilities, as 
well as Type R gas gathering pipelines.
    PHMSA also proposes revision of the property damage criterion 
within the definition of ``incident'' to exclude certain indirect costs 
associated with the cost incurred by operators in conducting repair 
activity. In particular, the revised definition excludes the cost of 
preparing and obtaining permits, as well as the removal and replacement 
of third-party infrastructure that was not itself damaged by the event. 
For example, if a release from a pipeline beneath a street did not 
damage a roadway, but pavement must be temporarily removed to repair 
the pipeline, the costs of the roadway repair and associated permits 
would not be included in the definition of property damage.

Sec.  191.11 Distribution System: Annual Report

    PHMSA proposes to change Form F7100.1-1 and its instructions to 
collect data on leaks detected and repaired by grade in the annual 
reporting period and the number (by grade) of unrepaired leaks at the 
conclusion of the annual reporting period. PHMSA also proposes to 
change the gas distribution annual report form to include estimated 
aggregate emissions from leaks by grade and other emissions categorized 
by source category (similar to those in the tables in section II.C) on 
an operator's system over the annual reporting period. PHMSA also 
proposes to revise miscellaneous sections of those annual reports and 
their instructions to remove statements expressing or suggesting that 
releases that can be eliminated by routine maintenance (such as 
lubrication, tightening, or adjustment) need not be reported as leaks. 
Such leaks and leak repairs would instead be recorded as a separate 
line item similar to the existing collection related to mechanical 
fitting failures to ensure a complete accounting of the number of 
releases from gas distribution pipelines.

Sec.  191.17 Transmission Systems; Gathering Systems; Liquefied Natural 
Gas Facilities; and Underground Natural Gas Storage Facilities; Annual 
Report

    PHMSA proposes to change the gas transmission and regulated 
gathering annual report form (Form F7100.2-1) and its instructions to 
collect data on leaks detected and repaired by grade during the annual 
reporting period. This form change is applicable to gas transmission, 
offshore gas gathering, and Type A, B, and C regulated onshore gas 
gathering pipelines. PHMSA also proposes to change Form F7100.2-1 to 
include estimated aggregate emissions from leaks by grade and other 
emissions by source category from an operator's system over the annual 
reporting period. PHMSA does not propose changes to the Type R annual 
report form (Form F7100.2-3). Lastly, PHMSA proposes to revise 
miscellaneous sections of the annual reports (and accompanying 
instructions) for each of gas transmission, offshore gathering, and 
regulated onshore gathering pipelines (Form F7100.2-1), Type R 
gathering pipelines (Form F7100.2-3) and LNG facilities (Form F7100.3-
1) to remove statements expressing or suggesting that releases that can 
be eliminated by routine maintenance (such as lubrication, tightening, 
or adjustment) need not be reported as leaks. A count of leaks 
eliminated by routine

[[Page 31955]]

maintenance would instead be reported as a separate line item on the 
annual report form.

Sec.  191.19 Large-Volume Gas Release Reports

    PHMSA proposes to create a new Sec.  191.19 requiring operators to 
submit reports of large-volume gas releases. Like incident reports, 
this requirement would be applicable to all operators of PHMSA-
jurisdictional gas pipeline facilities, including operators of 
jurisdictional underground storage and LNG facilities, as well as Type 
R gas gathering pipelines. The term ``large-volume gas release'' is 
defined in proposed amendments to Sec.  191.3, as described above. The 
report would be required for releases that become reportable on or 
after the effective date of a final rule.
    The new proposed report would require pertinent operators to report 
both intentional and unintentional releases of 1 MMCF or more of gas. 
This new form would capture both unintentional, fugitive emissions 
(e.g., from leaks) as well as blowdowns, maintenance related venting, 
pressure relief device actuations, and other intentional, vented 
emissions. Operators would be required to submit a report within 30 
days from the date that a release known at detection to be 1 MMCF or 
more was detected, or 30 days from the date that a previously detected 
release became reportable. If the time the leak started is unknown, 
operators should base the calculation based on estimated release volume 
from the date of the most recent leakage survey.
    PHMSA also notes that events reported as incidents under Sec. Sec.  
191.9 or 191.15 would not also need to be reported pursuant to the 
proposed Sec.  191.19 unless the total release volume at cessation 
exceeds 10% of the volume estimated in the incident report. If an 
unintentional release reported as a large-volume gas release report 
subsequently becomes reportable as an incident due to updated release 
volume estimates or consequences (or for any other reason), the 
operator would have to resubmit it as an incident report appropriate 
for the facility type.

Sec.  191.23 Reporting Safety-Related Conditions

    Consistent with PHMSA's current treatment of releases reportable as 
incidents, PHMSA proposes to except large-volume gas releases as 
defined in proposed Sec.  191.3 from the requirement to submit a 
safety-related condition report pursuant to Sec.  191.23. PHMSA also 
proposes to amend Sec.  191.23(a)(9) to explicitly limit that safety-
related condition reporting requirement to imminent hazards to public 
safety.

Sec.  191.29 National Pipeline Mapping System

    PHMSA proposed to delete the current exemption for offshore gas 
gathering, and Types A, B, and C gathering pipelines from NPMS 
reporting requirements at Sec.  191.29(a), thereby obliging operators 
of those pipelines to submit geospatial pipeline location data to NPMS. 
PHMSA does not propose to require operators of Type R, reporting-only, 
gas gathering lines to participate in the NPMS.

Sec.  192.3 Definitions

    Section 192.3 defines a number of terms that are referenced in part 
192. PHMSA proposes to add a few definitions, primarily those 
associated with leak detection and repair. These are primarily 
referenced in proposed Sec.  192.760 for the purposes of leak grading 
and repair requirements.
    PHMSA proposes to define a ``confined space'' as any subsurface 
structure, other than a building, of sufficient size to accommodate a 
person, and in which gas could accumulate or migrate. These would 
include vaults, catch basins, and manholes. Unlike a building, a 
confined space is not ordinarily occupied for residential, commercial, 
or industrial uses. The difference between a confined space and a 
substructure is that a confined space is large enough to accommodate a 
person, while a substructure is not. Consistent with the GPTC Guide, 
this definition differs from the definition of a ``confined space'' 
used by OSHA at 29 CFR 1910.146(b).
    PHMSA proposes to define a ``gas-associated substructure'' as a 
substructure that is part of an operator's pipeline facility but that 
is not itself designed to convey or store gas. These would typically 
consist of small vaults for devices, such as valves, meters, 
regulators, or other equipment.
    PHMSA proposes to define a ``substructure'' as any subsurface 
structure that is not large enough for a person to enter and in which 
gas could accumulate or migrate. Substructures would include telephone 
and electrical service boxes and associated ducts and conduits, valve 
boxes, and meter boxes.
    PHMSA proposes to define, for the purposes of all subparts of part 
192 other than IM requirements in Sec.  192.12(d) and subparts O and P, 
a ``leak or hazardous leak'' as any release of gas from a pipeline that 
is uncontrolled at the time of discovery and is an existing, probable, 
or future hazard to persons (including operating personnel), property, 
or the environment, or any uncontrolled release of gas from a pipeline 
that is detectable via equipment, sight, sound, smell, or touch. PHMSA 
proposes to require that each leak must be investigated, graded, and 
repaired in accordance with proposed Sec.  192.760. This includes leaks 
that are identified by the public or emergency personnel. Leaks include 
unintended releases through intended release pathways. For example, a 
pressure relief device or emergency shutdown device that fails and 
releases gas through a vent or flare is a leak.
    PHMSA proposes to define the ``lower explosive limit (LEL)'' as the 
minimum concentration of vapor in air below which propagation of a 
flame does not occur in the presence of an ignition source at ambient 
temperature and pressure. The LEL of natural gas is 5% methane in air 
by volume. The LEL for propane is 2.1% propane in air by volume. The 
LEL for hydrogen gas is 4% hydrogen by volume.
    PHMSA proposes to define a ``tunnel'' as a subsurface passageway 
large enough for a person to enter and in which gas could accumulate or 
migrate. Compared with a confined space, a tunnel is intended for 
regular or occasional human occupancy.
    PHMSA proposes to define a ``wall-to-wall paved area'' as an area 
where the ground surface between the curb of a paved street and the 
front wall of a building is continuously paved with hard top surface 
impermeable to gas, excluding non-continuous landscaping such as tree 
plots.

Sec.  192.9 What requirements apply to gathering lines?

    The NPRM proposes a series of amendments to Sec.  192.9 to improve 
protection of public safety and the environment from leaks and 
incidents on all part 192-regulated onshore and offshore gathering 
lines, and to improve alignment between the part 192 safety 
requirements applicable to each of Types A, B, and C gathering 
pipelines.
    Requirements for Type A gathering pipelines are defined in Sec.  
192.9(c), which requires that a Type A pipeline comply with the 
requirements of part 192 for transmission lines, subject to specific 
exceptions listed in that paragraph. PHMSA proposes no change to that 
paragraph. All Type A gathering pipelines would therefore be subject to 
the proposals introduced within the NPRM for transmission lines, 
including each of the following: revised definitions, to include a 
definition of ``leak or hazardous leak'' to account for environmental 
hazards in connection

[[Page 31956]]

with non-IM subparts of part 192 (Sec.  192.3); engineering analyses 
for the design of pressure relief devices (Sec.  192.199); modification 
of initial testing requirements to account for environmental hazards 
(Sec. Sec.  192.503, 192.507, 192.509, and 192.513); modification of 
procedural manuals to provide for elimination of leaks and minimize 
releases of gas as well as remediation or replacement of pipelines 
known to leak (Sec.  192.605); revision of failure investigation 
procedures for investigation of leaks (Sec.  192.617); enhanced 
patrolling requirements (Sec.  192.705); enhanced leakage survey 
requirements (Sec.  192.706); new leak grading, repair, and 
documentation requirements (Sec. Sec.  192.703(c) and (d), 192.709, 
192.760 and 192.763); new limitations on uprating pipelines (Sec. Sec.  
192.553 and 192.557); new leak detection personnel qualification 
requirements (Sec.  192.769); specific requirements for minimization of 
blowdown emissions (Sec.  192.770), and new pressure relief device 
maintenance requirements (Sec.  192.773). PHMSA also proposes that Type 
A gathering pipeline operators would be able to submit for PHMSA review 
a notification pursuant to Sec.  192.18 for flexibility with respect to 
each of the following: use of alternative leak detection equipment in 
non-HCA, Class 2 locations in complying with Sec.  192.706; use of an 
alternative performance standard in Class 2 locations in complying with 
Sec.  192.763; and extension of leak repair timelines set forth in 
Sec.  192.760.
    Part 192 requirements for Type B gathering pipelines are listed in 
Sec.  192.9(d); part 192 requirements not listed in Sec.  192.9(d) are 
generally inapplicable to Type B gathering pipelines. With respect to 
new, relocated, replaced, or otherwise changed Type B gathering lines, 
PHMSA proposes (consistent with its proposals for other regulated 
gathering lines) each of the following: a new Sec.  192.199 prescribing 
engineering analyses for the design of pressure relief devices; and 
modification of initial testing requirements to account for 
environmental hazards (Sec. Sec.  192.503, 192.507, 192.509, and 
192.513). PHMSA also proposes to revise Sec.  192.9(d) to add to the 
list of part 192 operations (subpart L) and maintenance (subpart M) 
requirements applicable to all Type B gathering pipelines a number of 
requirements for enhancing Type B operator leak detection, grading and 
repair programs, including the following: revised definitions, to 
include a definition of ``leak or hazardous leak'' to account for 
environmental hazards in connection with non-IM subparts of part 192 
(Sec.  192.3); introduction of procedural manuals providing for, among 
other things, the elimination of leaks and minimizing releases of gas 
as well as remediation or replacement of pipelines known to leak (Sec.  
192.605); patrolling requirements (Sec.  192.705); enhanced leakage 
survey requirements (Sec.  192.706); new leak grading, repair, and 
documentation requirements (Sec. Sec.  192.703(c) and (d), 192.709, 
192.760 and 192.763); and new pressure relief device maintenance 
requirements (Sec.  192.773). PHMSA has not proposed that operators of 
Type B gathering pipelines would be subject to new vented emissions 
mitigation requirements at proposed Sec.  192.770. Further, PHMSA's 
proposed revision referencing Sec.  192.605 procedural manual 
requirements would dispel any stakeholder confusion regarding whether 
Type B gathering pipelines are subject to the self-executing 
requirements at section 114 of the PIPES Act of 2020 to eliminate 
leaks, minimize releases of natural gas, and remediate or replace 
pipelines known to leak. PHMSA also proposes that Type B gathering 
pipelines would be subject to emergency response manual documentation 
requirements at Sec.  192.605 and emergency planning requirements at 
Sec.  192.615. Under Sec.  192.605(b)(1) and (b)(2), operators must 
include procedures for compliance with the subpart M and subpart I 
requirements applicable to the Type B lines in accordance with Sec.  
192.9, but they are not required to have procedures for other subparts 
M and I requirements. Similarly, operators of Type B gathering lines 
are not required to have procedures for complying with Sec.  192.631 
control room management requirements referenced in Sec.  
192.605(b)(12), nor for the continuing surveillance and accident 
investigation requirements referenced in Sec.  192.605(e). 
Additionally, PHMSA proposes that Type B gathering pipeline operators 
would be able to submit for PHMSA review a notification pursuant to 
Sec.  192.18 for flexibility with respect to each of the following: use 
of alternative leak detection equipment in non-HCA, Class 2 locations 
in complying with Sec.  192.706; extension of leak repair timelines set 
forth in Sec.  192.760; and use of an alternative performance standard 
in Class 2 locations in complying with Sec.  192.763.
    PHMSA also proposes a number of revisions to Sec.  192.9 paragraphs 
identifying specific part 192 requirements applicable to Type C 
gathering pipelines to promote alignment with regulatory requirements 
applicable to other regulated onshore gathering pipelines and reduce 
fugitive and vented emissions. Specifically, PHMSA proposes to revise 
Sec.  192.9(e) to expand the list of part 192 operations (subpart L) 
and maintenance (subpart M) requirements applicable to all Type C 
gathering pipelines to include a number of requirements to enhance Type 
C operator leak detection, grading and repair programs, including the 
following: revised definitions, to include a definition of ``leak or 
hazardous leak'' to account for environmental hazards in connection 
with non-IM subparts of part 192 (Sec.  192.3); procedural manuals 
providing for, among other things, elimination of leaks and minimize 
releases of natural gas as well as remediation or replacement of 
pipelines known to leak (Sec.  192.605); patrolling requirements (Sec.  
192.705); enhanced leakage survey requirements (Sec.  192.706); new 
leak grading, repair, and documentation requirements (Sec. Sec.  
192.703(c) and (d), 192.709, 192.760 and 192.763); and pressure relief 
device maintenance requirements (Sec.  192.773). PHMSA also proposes 
that new, replaced, relocated, or changed Type C gathering lines would 
be subject to the pressure relief device design and configuration 
requirements at Sec.  192.199, as well as modification of initial 
testing requirements to account for environmental hazards (Sec. Sec.  
192.503, 192.507, 192.509, and 192.513). PHMSA has not proposed that 
operators of Type C gathering pipelines would be subject to its 
proposed new limitations on uprating pipelines at Sec. Sec.  192.553 
and 192.557, or the vented emissions mitigation requirements at 
proposed Sec.  192.770. PHMSA also proposes revision to Sec.  
192.9(f)(1) to narrow the exceptions identified in that subparagraph to 
ensure that all Type C gathering pipelines are subject to leakage 
survey and repair requirements. Further, PHMSA's proposed revision 
referencing Sec.  192.605 procedural manual documentation requirements 
would dispel any stakeholder confusion regarding whether Type C 
gathering pipelines must have emergency response manuals, or are 
subject to the self-executing requirements at section 114 of the PIPES 
Act of 2020 to eliminate leaks, minimize releases of natural gas, and 
replace or remediate pipelines known to leak. Under Sec.  192.605(b)(1) 
and (b)(2), operators must include procedures for compliance with the 
subpart M and subpart I requirements applicable to the Type C

[[Page 31957]]

pipeline in accordance with Sec.  192.9, but they are not required to 
have procedures for other subparts M and I requirements. Similarly, 
operators are only required to have procedures for submitting safety-
related condition reports on Type C gathering lines if the pipeline is 
subject to the safety-related condition reporting requirement in Sec.  
191.23 (i.e., the pipeline is required to have an MAOP). Further, 
operators of Type C gathering lines are not required to have procedures 
for complying with Sec.  192.631 control room management requirements 
referenced in Sec.  192.605(b)(12), nor for the continuing surveillance 
and accident investigation requirements referenced in Sec.  192.605(e). 
PHMSA also proposes that Type C gathering pipeline operators would be 
able to submit for PHMSA review a notification pursuant to Sec.  192.18 
for flexibility in each of the following: use of alternative leak 
detection equipment in non-HCA, Class 1 locations in complying with 
Sec.  192.706; use of an alternative performance standard in Class 1 
locations in complying with Sec.  192.763; and extension of leak repair 
timelines set forth in Sec.  192.760.
    Lastly, PHMSA proposes minor changes to the language in Sec.  
192.9(b) listing part 192 requirement to which offshore gas gathering 
pipelines are exempt: specifically, PHMSA has added language stating 
explicitly that offshore gas gathering pipelines would be exempt from 
the default grade 2 classification requirement and at Sec.  
192.763(c)(1)(vi) and the 30-day repair requirement at Sec.  
192.763(c)(3). PHMSA has not otherwise proposed to modify Sec.  
192.9(b). However, because PHMSA is proposing a number of revisions to 
part 192 requirements applicable to gas transmission lines, those 
proposed requirements would apply to offshore gathering pipelines as 
well pursuant to Sec.  192.9(b). Specific proposals that would apply to 
offshore gathering pipelines include each of the following: revised 
definitions, to include a definition of ``leak or hazardous leak'' to 
account for environmental hazards in connection with non-IM subparts of 
part 192 (Sec.  192.3); engineering analyses for the design of pressure 
relief devices (Sec.  192.199); modification of initial testing 
requirements to account for environmental hazards (Sec. Sec.  192.503, 
192.507, 192.509, and 192.513); new limitations on uprating pipelines 
(Sec. Sec.  192.553 and 192.557); modification of procedural manuals to 
provide for elimination of leaks and minimize releases of gas as well 
as remediation or replacement of pipelines known to leak (Sec.  
192.605); revision of failure investigation procedures for 
investigation of leaks (Sec.  192.617); enhanced patrolling 
requirements (Sec.  192.705); enhanced leakage survey requirements 
(Sec.  192.706); new leak grading, repair, and documentation 
requirements (Sec. Sec.  192.703(c) and (d), 192.709, 192.760 and 
192.763); new leak detection personnel qualification requirements 
(Sec.  192.769); specific requirements for minimization of blowdown 
emissions (Sec.  192.770), and new pressure relief device maintenance 
requirements (Sec.  192.773). PHMSA also proposes that offshore gas 
gathering pipeline operators would be able to submit for PHMSA review a 
notification pursuant to Sec.  192.18 for flexibility with respect to 
each of the following: use of an alternative ALDP performance standard 
in complying with Sec.  192.763; and extension of leak repair timelines 
set forth in Sec.  192.760. PHMSA has not proposed that offshore gas 
gathering pipelines would be subject to its proposed default 
requirement within Sec.  192.763 for any leak be considered a grade 2 
leak at a minimum.

Sec.  192.12 Underground Natural Gas Storage Facilities

    Section 192.12(c) obliges operators of underground natural gas 
storage facilities to have and follow written procedures for 
operations, maintenance, and emergency response activities. PHMSA 
proposes to revise the regulatory language in this provision to 
incorporate within its regulations the section 114 of the PIPES Act of 
2020 self-executing mandate that operators update their procedures to 
provide for the elimination of leaks and minimize release of gas from 
pipeline facilities.

Sec.  192.18 How To Notify PHMSA

    PHMSA proposes to revise Sec.  192.18(c) to cross reference 
proposed amendments in the NPRM that allow an operator flexibility in 
complying with certain part 192 requirements. Specifically, the NPRM 
proposes to allow operators to use alternative compliance approaches 
with advance notification to PHMSA in connection with the following 
requirements: use of leak detection equipment for leakage surveys on 
onshore gas transmission and certain regulated gathering pipelines 
(Sec.  192.706(a)(2)); for each of natural gas transmission and 
gathering operators with pipelines in Class 1 or 2 locations, as well 
as operators of any part 192-regulated gas pipeline transporting gas 
other than natural gas, implementation of an alternative ALDP 
performance standard as well as alternative leak detection equipment 
(Sec.  192.763(c)); and minimum leak repair schedules (Sec.  
192.760(h)). Each of these flexibilities is described separately under 
its respective discussion in this section V. As specified in existing 
Sec.  192.18, an operator must notify PHMSA 90 days in advance of using 
an alternative compliance approach and may begin to use that 
alternative approach if they do not receive a letter after 90 days 
objecting to that alternative compliance approach from PHMSA.

Sec.  192.167 Compressor Stations: Emergency Shutdown

    PHMSA proposes to revise Sec.  192.167(a)(2) governing on new, 
replaced, relocated, or otherwise changed compressor stations on gas 
transmission and part 192-regulated onshore gas gathering pipelines to 
state that blowdowns of those facilities during emergency shutdowns 
must be directed toward locations where the released gas would not 
create a hazard to public safety specifically.

Sec.  192.169 Compressor Stations: Pressure Limiting Devices

    PHMSA proposes to revise Sec.  192.169(b) governing on new, 
replaced, relocated, or otherwise changed gas compression stations on 
gas transmission pipelines and boosting stations on part 192-regulated 
gathering pipelines to state that vent lines from pressure relief 
devices must exhaust gas to locations that would not create a hazard to 
public safety specifically.

Sec.  192.179 Transmission Line Valves

    PHMSA proposes to revise Sec.  192.179(c) governing blowdown valves 
on new, replaced, relocated, or otherwise changed gas transmission and 
Types A, B, and C gathering pipelines to state that the discharges from 
those valves must be located such that blowdowns to atmosphere would 
not create a hazard to public safety specifically.

Sec.  192.199 Requirements for Design and Configuration of Pressure 
Relief and Limiting Devices

    PHMSA proposes to revise Sec.  192.199 to require that all new, 
replaced, relocated, or otherwise changed overpressure protection 
devices be designed and configured to minimize unnecessary releases of 
gas to the atmosphere. Since Sec.  192.199 is a generally applicable 
design requirement, this proposed amendment would apply to all 
facilities regulated under part 192, including gas transmission, 
distribution, offshore gas gathering, and Types A, B, and C onshore gas 
gathering pipelines. This requirement would not be retroactive,

[[Page 31958]]

and thus would not apply to any pressure relief device on pipelines 
existing on or before the effective date of the rule unless the 
pipeline is subsequently replaced, relocated, or otherwise changed.
    To comply with this proposed requirement, each pressure relief 
device must be designed and configured based on a documented 
engineering analysis demonstrating that the set and reset conditions of 
the device, as well as the size and configuration of it and its 
associated piping, are appropriate for providing adequate overpressure 
protection. Additionally, the design and materials used for the relief 
device must be compatible with the composition of the gas being 
transported and be suitable for the anticipated operating and 
environmental conditions. The design of the relief device would need to 
include isolation valves to support testing and maintenance.
    Lastly, PHMSA proposes revision of Sec.  192.199(e) to require that 
all new, replaced, relocated, or otherwise changed pressure relief and 
limiting devices on gas transmission, distribution, offshore gas 
gathering, and Types A, B, and C gas gathering pipelines would need to 
have discharge stacks, vents, or outlet ports located where gas can be 
discharged into the atmosphere without undue hazards to public safety 
specifically.

Sec.  192.361 Service Lines: Installation

    PHMSA proposes revision of Sec.  192.631(f)(3) governing new, 
replaced, relocated, or otherwise changed underground service lines 
installed under buildings to provide that vents from service line 
annular spaces must be to locations that would not create a hazard to 
public safety specifically.

Sec.  192.363 Service Lines: Valve Requirements

    PHMSA proposes revision of Sec.  192.363(c) governing design and 
construction requirements for valves on high-pressure service lines to 
limit that requirement to, among other things, certain high-pressure 
service lines installed in areas where blowdowns of gas would be 
hazardous to public safety specifically.

Sec.  192.503 General Requirements

    PHMSA proposes to revise Sec.  192.503(a)(2) governing initial 
testing requirements on new, replaced, relocated, or otherwise changed 
gas transmission, distribution, and part 192-regulated gathering 
pipelines to delete the qualification ``potentially'' modifying 
``hazardous leak'' in recognition of the certainty of environmental 
harms from any released natural gas, flammable gas, toxic gas, or 
corrosive gas.

Sec.  192.507 Test Requirements for Pipelines To Operate at a Hoop 
Stress Less Than 30 Percent of SMYS and at or Above 100 p.s.i. (689 
kPa) Gage

    PHMSA proposes to revise Sec.  192.507(a) governing certain initial 
testing requirements on new, replaced, relocated, or otherwise changed 
gas transmission, distribution, and part 192-regulated gathering 
pipelines to delete the qualification ``potentially'' modifying 
``hazardous leak'' in recognition of the certainty of environmental 
harms from any released gas.

Sec.  192.509 Test Requirements for Pipelines To Operate Below 100 
p.s.i. (689 kPa) Gage

    PHMSA proposes to revise Sec.  192.509(a) governing initial testing 
requirements on new, replaced, relocated, or otherwise changed gas 
transmission, distribution, and part 192-regulated gathering pipelines 
(other than service and plastic pipelines) to delete the qualification 
``potentially'' modifying ``hazardous leak'' in recognition of the 
certainty of environmental harms from any released gas.

Sec.  192.513 Test Requirements for Plastic Pipelines

    PHMSA proposes to revise Sec.  192.513(b) governing initial testing 
requirements on new, replaced, relocated, or otherwise changed plastic 
gas transmission, distribution, and part 192-regulated gathering 
pipelines to delete the qualification ``potentially'' modifying 
``hazardous leak'' in recognition of the certainty of environmental 
harms from any released gas. PHMSA also proposes an editorial 
correction of the word ``insure'' to ``ensure.''

Sec.  192.553 General Requirements

    PHMSA proposes to revise the general requirements for uprating to 
clarify that any hazardous leaks detected during the uprating process 
on gas transmission, distribution, offshore gathering, and Type A 
gathering lines must be repaired prior to further increasing the 
pressure of the pipeline during the incremental pressure increase 
procedure in Sec.  192.553(a). This requirement would apply to any gas 
transmission, distribution, or Type A gathering pipeline subjected to 
an incremental increase in operating pressure as described in Sec.  
192.553.

Sec.  192.557 Uprating: Steel Pipelines to a Pressure That Will Produce 
a Hoop Stress Less Than 30 Percent of SMYS: Plastic, Cast Iron, and 
Ductile Iron Pipelines

    PHMSA proposes to revise Sec.  192.557(b)(2) to require that 
operators of gas transmission, distribution, offshore gathering, and 
Type A gathering pipelines repair any hazardous leaks (note that PHMSA 
proposes to define leaks and hazardous leaks identically in Sec.  
192.3) that are found prior to uprating a pipeline that will operate at 
an MAOP producing a hoop stress less than 30 percent of SMYS, or that 
is made of plastic, cast iron, or ductile iron. A pipeline with an 
active leak would therefore not be permitted to be uprated to a higher 
MAOP until each leak repair was complete.

Sec.  192.605 Procedural Manual for Operations, Maintenance, and 
Emergencies

    Existing Sec.  192.605 requires each operator of an onshore or 
offshore gas transmission pipeline, gas distribution pipeline, offshore 
gas gathering pipeline, or Type A gas gathering pipeline to prepare and 
follow a written procedure manual for operations, maintenance, and 
emergency response activities. PHMSA proposes to revise Sec.  192.9 to 
extend those procedural documentation requirements to Types B and C gas 
gathering pipelines, excluding requirements for procedures that are not 
applicable to such pipelines. PHMSA also proposes to revise Sec.  
192.605 to incorporate the self-executing mandate at section 114 of the 
PIPES Act of 2020 that the maintenance and operating procedures for 
part 192-regulated gas pipelines must include procedures for each of 
the elimination of leaks and for minimizing releases of gas from 
pipelines, as well as the remediation or replacement of pipelines known 
to leak based on their material, design, or past maintenance and 
operating history. These proposed amendments to Sec. Sec.  192.9 and 
192.605 would dispel any stakeholder uncertainty regarding application 
of the self-executing requirements in section 114 of the PIPES Act of 
2020.

Sec.  192.617 Investigation of Failures

    For the purposes of the existing requirement to investigate 
failures, PHMSA proposes to define the term ``failure'' for the 
purposes of Sec.  192.617 to mean ``when any portion of a pipeline 
becomes inoperable, is incapable of safely performing its intended 
function, or has become

[[Page 31959]]

unreliable or unsafe for continued use.'' PHMSA considers any leaking 
gas pipeline as having failed to perform its intended function. This 
proposed regulatory amendment would apply to gas distribution, gas 
transmission, offshore gas gathering, and Type A regulated onshore gas 
gathering pipelines.

Sec.  192.629 Purging of Pipelines

    PHMSA proposes to revise its provisions governing the purging of 
gas from each of gas transmission, distribution, offshore gathering and 
Type A gathering pipelines to clarify that this provision remains 
focused on addressing risks to public safety associated with purging of 
gas from those pipelines. PHMSA also proposes editorial amendments 
replacing the term ``released'' with ``introduced'' to more accurately 
reflect that gas is being injected into the pipeline and replacing the 
term ``line'' with ``pipeline.''

Sec.  192.703 General

    As discussed above and below, PHMSA is proposing to delete the 
historical reference to ``hazardous leak'' in Sec.  192.703 (which 
qualification limited the general repair requirement in that provision) 
and replace it with a reference to PHMSA's proposed Sec.  192.760 leak 
grading and repair requirements. PHMSA's proposed revisions to 
Sec. Sec.  192.703 (when coupled with proposed amendments to Sec.  
192.9) would extend the scope of the Sec.  192.703 general leak repair 
requirement to all part-192 regulated gas pipelines.
    PHMSA also proposes an exception from proposed requirements listed 
in Sec.  192.703(d) for gas transmission compression and gathering 
boosting stations subject to EPA methane emissions monitoring and 
repair requirements within current 40 CFR part 60, subpart OOOOa 
regulations; proposed subpart OOOOb updates and subpart OOOOc methane 
emissions guidelines (as implemented through EPA-approved State plans 
with standards at least as stringent as EPA's emission guidelines in 
subpart OOOOc or implemented through a Federal plan).\295\ Specific 
proposed requirements from which eligible stations would be excepted 
include the following: leak repair (Sec.  192.703(c)), leakage survey 
and patrol (Sec. Sec.  192.705 and 192.706), leak grading and repair 
(Sec.  192.760), ALDPs (Sec.  192.763), and qualification of leak 
detection personnel (Sec.  192.769).
---------------------------------------------------------------------------

    \295\ EPA, ``Standards of Performance for New, Reconstructed, 
and Modified Sources and Emissions Guidelines for Existing Sources: 
Oil and Natural Gas Sector Climate Review,'' 87 FR 74702 (Dec. 6, 
2022).
---------------------------------------------------------------------------

Sec.  192.705 Transmission Lines: Patrolling

    Visual right-of-way patrols with or without the use of leak 
detection equipment are required by Sec.  192.705 on gas transmission 
lines and are an important supplement to leakage surveys. PHMSA 
proposes to increase the minimum required frequency of right-of-way 
patrols on gas transmission, offshore gathering, and Type A gathering 
pipelines to at least 12 times each calendar year, with intervals 
between patrols not exceeding 45 days, regardless of location. PHMSA 
also proposes to revise Sec.  192.9 to require operators perform 
patrols of Type B and Type C regulated onshore gas gathering pipelines 
on the same interval. An operator may combine a patrol pursuant to 
Sec.  192.705 with a leakage survey pursuant to Sec.  192.706, provided 
their procedures include both a visual survey of the right-of-way and a 
leakage survey with leak detection equipment.

Sec.  192.706 Transmission Lines: Leakage Surveys

    PHMSA proposes to revise Sec.  192.706 to increase the minimum 
frequency for performing leakage surveys of gas transmission, offshore 
gas gathering, and Types A, B, and C gathering pipelines, each located 
in HCAs in Class 1, Class 2, and Class 3 locations, to twice each 
calendar year at intervals not exceeding 7\1/2\ months. PHMSA also 
proposes revision of Sec.  192.9 to extend Sec.  192.706 leak survey 
requirements to all Type C gathering pipelines. Further, PHMSA proposes 
to increase the minimum frequency for performing leakage surveys of gas 
transmission and Types A and B gathering pipelines located in HCAs in 
Class 4 locations to four times each calendar year at intervals not 
exceeding 4\1/2\ months.
    PHMSA proposes to require each leakage survey on an onshore gas 
transmission pipeline or Type A, B, or C gathering pipeline to be 
performed using leak detection equipment and methods that meet the ALDP 
performance standard in the proposed Sec.  192.763. This proposed 
change would eliminate the existing automatic, generically available 
exception at Sec.  192.625 from requirements to use leak detection 
equipment for gas transmission and Types A and B gathering pipelines in 
Class 1 and Class 2 locations and odorized pipelines in Class 3 and 
Class 4 locations. Leakage surveys for onshore gas transmission and 
Types A, B, and C gathering pipelines would only be performed without 
the use of leak detection equipment (i.e., solely with the use of human 
or animal senses) with prior notification and review by PHMSA in 
accordance with Sec.  192.18, and may only be approved in non-HCA, 
Class 1, and Class 2 locations. Leakage surveys for offshore gas 
transmission and offshore gathering pipelines would not require the use 
of leak detection equipment. PHMSA has not proposed changes to the 
requirements for leakage surveys for gas transmission and gathering 
pipelines located outside of HCAs, or for gas transmission and 
gathering pipelines operating without an odor or odorant.
    PHMSA also proposes more frequent leakage surveys for all valves, 
flanges, tie-ins with valves and flanges, ILI launcher and receiver 
facilities on gas transmission, offshore gathering, and Types A, B, and 
C gathering lines. PHMSA similarly proposes more frequent leakage 
surveys for those gas transmissions, offshore gathering, and Types A, 
B, and C gathering pipelines known to leak based on material, design, 
or past operating and maintenance history. Each such facilities 
identified in this paragraph located in Class 1, Class 2, and Class 3 
locations must be surveyed twice each calendar year, and those in Class 
4 locations must be surveyed at least four times each calendar year.

Sec.  192.723 Distribution: Leakage Surveys

    PHMSA proposes defining minimum standards for leak survey practices 
and equipment on gas distribution pipelines through reference to the 
proposed ALDP performance standard in Sec.  192.763. This proposal 
would replace the existing requirement at Sec.  192.723 to use leak 
detection equipment and is described in more detail under the 
discussion of that section below.
    PHMSA also proposes to increase the frequency of leakage surveys on 
most gas distribution pipelines outside of business districts to once 
every 3 calendar years, with an interval between surveys not to exceed 
39 months. Operators whose procedures or DIMP call for more frequent 
leakage surveys would be obliged to conduct leakage surveys 
accordingly. And distribution pipelines outside of business districts 
at a high risk of leakage would generally be obliged to conduct leakage 
surveys more frequently: once each calendar year, with the interval 
between surveys not to exceed 15 months. The following distribution 
pipelines outside of business districts would be subject to PHMSA's 
proposed new annual survey requirement:

[[Page 31960]]

    1. Cathodically unprotected pipelines on which electrical surveys 
are impracticable. This would typically cover bare and unprotected 
distribution lines;
    2. Pipelines known to leak based on their material (including, but 
not limited to, cast iron, unprotected steel, wrought iron, and 
historic plastics with known issues), design, or past operating and 
maintenance history; and
    3. Any distribution pipeline protected by a distributed anode 
system where the cathodic protections survey under Sec.  195.463 showed 
a deficient reading during the most recent cathodic protection survey.
    In determining whether a plastic pipeline is made of a ``historic 
plastic with known issues'' operators should consider PHMSA and State 
regulatory actions and industry technical resources identifying 
systemic integrity issues from plastic pipe that is either comprised of 
particular materials; or manufactured at particular times, by 
particular companies, or pursuant to particular processes.
    In addition to the above, PHMSA proposes to require, as soon as 
practicable following ground freezing, heavy rain, flooding, or other 
environmental conditions that may affect the venting of gas or cause 
gas migration to nearby buildings, reinvestigation of known leaks 
(including conducting a leakage survey for possible gas migration). 
This investigation is to determine whether changes to gas migration or 
to the facility itself have created a hazard that requires upgrading 
the leak. Generally, any surface freezing or frost and any flooding 
near the leak location is likely to affect gas venting and migration 
through the soil. When determining if heavy rain is likely to affect 
the venting or migration of leaking gas through the soil, operators 
should consider the estimated flow rate of the leak, rate of rainfall, 
local soil conditions, drainage, the presence of other nearby buried 
structures, and whether the area has a history of flooding.
    PHMSA also proposes to require leakage surveys of a distribution 
pipeline soon (initiated within 72 hours) after the cessation of 
extreme weather events or land movement that could damage that pipeline 
segment. PHMSA defines the cessation of the event as either the time 
that the facility becomes safely accessible to operator personnel, or 
alternatively the time that the pipeline facility is placed back into 
service.

Sec.  192.727 Abandonment or Deactivation of Facilities

    PHMSA proposes to revise Sec.  192.727(b) and (c) governing 
abandonment of gas transmission, distribution, offshore gathering, and 
Type A gathering pipelines to provide that the existing exception for 
small gas purge volumes in those paragraphs would be available if 
purging would not create a risk to public safety specifically.

Sec.  192.751 Prevention of Accidental Ignition

    PHMSA proposes to revise Sec.  192.751(a) governing gas 
transmission, offshore gathering, and Type A gathering pipelines to 
clarify that the hazards being addressed in that provision are hazards 
to public safety specifically. PHMSA also proposes an editorial 
amendment clarifying that a fire extinguisher must be present, rather 
than provided, during venting of gas.

Sec.  192.760 Leak Grading and Repair

    PHMSA proposes to create a new Sec.  192.760 addressing 
requirements for grading and repairing leaks on gas distribution, 
transmission, offshore gathering, and Types A, B, and C gathering 
pipelines. The leak grading concept and many of the leak grading 
criteria are similar to those in the GPTC Guide, which has been adopted 
in some operator procedures and State pipeline safety requirements.

Sec.  192.760(a): General

    Section 192.760(a) would require operators to have and carry out 
written procedures for grading and repairing leaks that meet or exceed 
the minimum requirements of Sec.  192.760. PHMSA's proposed 
requirements in this paragraph also clarify that Sec.  192.760 would 
apply to any leak detected by the operator and applies to all 
components of pipelines (including, but not limited to, pipeline pipe, 
valves, flanges, meters, regulators, tie-ins, launchers, and 
receivers). Operators must investigate any leaks discovered immediately 
and continuously until a leak grade determination has been made.

Sec.  192.760(b): Grade 1 Leaks

    PHMSA proposes to characterize a grade 1 leak as an existing or 
probable hazard to persons and property or grave hazard to the 
environment. A grade 1 leak is an urgent or emergency situation and 
this NPRM proposes to require an operator take immediate and continuous 
action to eliminate any hazard to public safety and the environment and 
to promptly complete repair. PHMSA's proposed paragraph (b)(2) includes 
a list of actions the operator may take to address any hazard pending 
repair. These steps include activating the operator's emergency plan 
under Sec.  192.615, evacuating or blocking off the vicinity of the 
leak, rerouting traffic, eliminating ignition sources, ventilating the 
leak area to disperse hazardous accumulations of gas, stopping the flow 
of gas in the facility, or notifying emergency responders. While some 
of these actions, such as bar holing near the leak, may reduce gas 
concentration, proposed Sec.  192.760(e) would not allow downgrading a 
leak to a lower-priority leak grade unless a repair has been made. The 
operator would have to promptly complete repair even if gas 
concentration falls to grade 2 or grade 3 levels after the leak 
location has been vented.
    Paragraph (b)(1) provides minimum criteria for grade 1 leaks that 
would need to be included in operators' leak grading procedures as they 
demonstrate that a leak poses an existing or probable hazard to public 
safety or grave hazard to the environment. Operator procedures may 
supplement those proposed minimum grade 1 criteria as desired. Specific 
criteria include the following: any leak that operating personnel at 
the scene determine is an existing or probable hazard to public safety 
or a grave hazard to the environment; any leak that has ignited; any 
indication of potential for ignition of accumulated gas resulting from 
gas migrating into a building, under a building, or into a tunnel; any 
indication of potential for ignition due to accumulated gas due to 
migration of gas to the outside wall of a building or to an area from 
which migration to the outside wall of a building could occur; gas 
concentration readings approaching LEL within either of a confined 
space or a substructure from which gas could migrate to the outside of 
a building; any leak that can be seen, heard, or felt; and any leak 
that is an incident pursuant to Sec.  191.3.

Sec.  192.760(c): Grade 2 Leaks

    PHMSA proposes to characterize a grade 2 leak as a leak with a 
probable future hazard to public safety or a significant hazard to the 
environment. There are currently no explicit Federal pipeline safety 
requirements to repair such leaks; however, some States and operators 
have adopted the GPTC Guide, which requires operators to repair such 
leaks within 12 months of detection. PHMSA proposes to require a grade 
2 leak repair be completed within six months in most circumstances, 
however certain leaks would have shorter repair deadlines.

[[Page 31961]]

    The proposed minimum criteria for grade 2 leaks reflect gas 
readings suggesting that a leak has a probable, future hazard to public 
safety or a significant hazard to the environment, but there is not an 
existing or probable hazard to public safety or a grave hazard to the 
environment as a grade 1 leak entails. Operator procedures may 
supplement those proposed minimum grade 2 criteria as desired. Among 
PHMSA's proposed minimum criteria are leaks, other than grade 1 leaks, 
producing a gas reading of 40% LEL or greater under a sidewalk in a 
wall-to-wall paved area, or a reading of 100% or greater under a street 
in a wall-to-wall paved area with gas migration that is not a grade 1 
leak. Similar to the grade 1 criteria, the grade 2 criteria include 
criteria based on readings within confined spaces and substructures. A 
leak reading between 20% LEL and 80% of LEL in a confined space is a 
grade 2 leak. Unlike the grade 1 criteria, however, the grade 2 
criteria make a distinction between gas readings in gas-associated and 
non-gas associated substructures. A leak must be classified as grade 2 
if it produces a reading less than 80% LEL in a non-gas associated 
substructure from which gas could migrate. A leak with a reading of 80% 
LEL or greater in a gas associated substructure from which gas could 
migrate must be classified as a grade 2 leak. Like the grade 1 
criteria, this NPRM proposes to require that operators' procedures 
allow operating personnel at the scene to decide that a leak justifies 
repair on a grade 2 schedule.
    Similar to the discussion of grade 1 leaks, there are differences 
between the grade 2 criteria proposed in this NPRM and the grade 2 
criteria in the GPTC Guide. To ensure timely repair of leaks with 
relatively large emissions, PHMSA proposes to require that any leak 
other than a grade 1 leak with a leakage rate of 10 CFH) or more be 
classified as a grade 2 leak. Additionally, in the NPRM, grade 2 is the 
minimum grade for any leak on a gas transmission pipeline or Type A or 
C gathering pipeline, or any leak of LPG or hydrogen that does not 
qualify as grade 1 leak.
    PHMSA proposes to require that operators repair grade 2 leaks 
within 6 months of detection, or any alternative timeline identified in 
an operator's procedures or IM plan, whichever is earlier. Operators 
must reevaluate each grade 2 leak once every 30 days until the leak 
repair is completed or the leak is cleared (or, if a grade 2 leak must 
be repaired within 30 days, every 2 weeks until the repair has been 
completed). However, PHMSA proposes to require operators to prioritize 
repair of some grade 2 leaks based on their higher potential for public 
safety and environmental consequences. For example, PHMSA proposes to 
require any leak on a gas transmission or Type A gathering pipeline, 
each in an HCA or a Class 3 or Class 4 location (and that is not a 
grade 1 leak) to be repaired within 30 days of detection, or the 
operator must take continuous action to monitor and repair the leak. 
Additionally, PHMSA proposes to require each operator's leak grading 
and repair procedures to include a methodology for prioritizing grade 2 
leak repairs, including criteria for leaks that must be repaired within 
30 days or less. The operator's methodology must include an analysis of 
the volume and migration of gas emissions, the proximity of gas to 
buildings and subsurface structures, the extent of pavement, and soil 
type and conditions that affect the possibility for gas migration such 
as frost conditions or soil moisture. This NPRM also proposes to 
require an operator complete repair of an existing grade 2 leak or take 
other immediate and continuous action to complete repairs and eliminate 
hazards when changing environmental conditions that may affect the 
venting or migration of gas that could allow gas to migrate to the 
outside wall of a building. Environmental changes that could contribute 
to gas migration include ground freezing, heavy rains or flooding, or 
the installation of new pavement.
    Finally, PHMSA proposes to require that operators complete repairs 
of grade 2 leaks known to exist on or before the effective date of the 
rule within 1 year from the date of publication of the final rule.

Sec.  192.760(d): Grade 3 Leaks

    PHMSA proposes to characterize a grade 3 leak as any leak that does 
not meet its minimum proposed grade 1 or grade 2 criteria. Like grade 2 
leaks, there is no current Federal standard requiring repair of such 
leaks, and the GPTC Guide does not require a minimum repair schedule. 
Illustrative examples of grade 3 leaks as contemplated by this NPRM 
include (but are not limited to) leaks with a reading of less than 80% 
LEL in gas-associated substructures from which gas is unlikely to 
migrate, any reading of gas under pavement outside of wall-to-wall 
paved areas where it is unlikely that gas could migrate to the outside 
wall of a building, or a reading of less than 20% LEL in a confined 
space.
    PHMSA proposes to require an operator to complete repair of each 
grade 3 leak within 24 months of the date the leak was detected and 
require each grade 3 leak be re-evaluated once every six months until 
the leak repair has been completed. However, PHMSA proposes to allow an 
operator to continue to monitor a grade 3 leak provided the pipeline 
segment containing the leak is scheduled for replacement and is in fact 
replaced, within five years of the date the leak was detected. Finally, 
PHMSA proposes to require a grade 3 leak known to exist on or before 
the effective date of the rule be repaired within 3 years from the date 
of publication of the final rule, unless the pipeline is scheduled for 
replacement within five years from the effective date of the rule.

Sec.  192.760(e): Post-Repair Inspection

    PHMSA in proposed Sec.  192.760(e) defines requirements for 
determining and documenting that a complete and effective repair of a 
leak has been accomplished. PHMSA proposes to require that, in order 
for a leak repair to be complete, an operator must perform a permanent 
repair and obtain, during a post-repair inspection, a gas concentration 
reading of 0% gas at the leak location. A temporary repair may be used 
to downgrade a leak in accordance with proposed Sec.  192.760(g). 
Proposed Sec.  192.760(e)(2) would require that the first post-repair 
inspection be completed no sooner than 14 days but no later than 30 
days after the date of repair.
    Proposed Sec.  192.760(e)(3) provides for enhanced repair and 
monitoring requirements if a post-repair inspection yields a gas 
reading greater than 0% gas. Specifically, if a post-repair inspection 
indicates that a grade 1 or 2 condition exists, the operator would need 
to reevaluate the repair and take immediate and continuous action to 
eliminate the hazard and complete the repair. If a grade 1 or grade 2 
condition did not exist, the operator would need both to re-inspect the 
leak every 30 days and complete the repair within either of the repair 
deadline for a grade 3 leak under Sec.  192.760(d)(2) or (for a leak 
that was downgraded after the initial repair) a new repair deadline 
established under Sec.  192.760(g). Lastly, proposed Sec.  
192.760(e)(4) would provide that post-repair inspection would not be 
necessary if leak remediation was completed via routine maintenance 
activities such as cleaning, lubrication, or adjustment.

Sec.  192.760(f) and (g): Upgrading and Downgrading

    Proposed Sec.  192.760(f) and (g) describe the repair deadlines and 
requirements for leaks that are upgraded or

[[Page 31962]]

downgraded to higher or lower -priority grades. Operators who receive 
information that a higher-priority grade condition exists on a 
previously graded leak would need to upgrade that leak to a higher-
priority grade. For a leak that is upgraded, PHMSA proposes to require 
that the deadline for the repair would be the earlier of either the 
remaining time based on the original leak grade, or the time allowed 
for repair for the upgraded leak measured from the time the operator 
receives information that a higher-priority grade condition exists. In 
other words, an operator would not be permitted to extend the repair 
deadline by upgrading a leak.
    PHMSA also proposes to prohibit downgrading of a leak unless a 
temporary repair has been made or a permanent repair to the pipeline 
has been attempted but gas was detected during the post-repair 
inspection required by proposed Sec.  192.760(e). For example, a leak 
may not be downgraded simply by venting the leak location until gas 
measurements fall to grade 3 levels, with no action taken to 
permanently remediate the leak. A leak may be downgraded if the 
facility was the subject of an attempt at permanent repair, but a non-
zero reading was measured during the post-repair inspection described 
in the discussion of Sec.  192.760(e). If a leak were downgraded after 
the attempted permanent repair, the time period for completion of 
repair would be the remaining time allowed for repair under its new 
grade, measured from the time the leak was initially detected.

Sec.  192.760(h) Extension of Leak Repair

    PHMSA proposes to allow an extension of the repair deadline 
requirements for individual grade 3 leaks only on a case-by-case basis. 
This extension requires notification to, and review by, PHMSA pursuant 
to the procedures in Sec.  192.18. An operator may request an extension 
if the delayed repair timeline would not result in increased risks to 
public safety, and the operator can demonstrate either that the 
prescribed repair schedule is impracticable, an alternative repair 
schedule is necessary for safety, or remediation within the specified 
time frame would result in the release of more gas to the environment 
than would otherwise occur if the leak were allowed to continue. For 
example, if the repair of a grade 3 leak would require significant 
emissions to blowdown the facility, delaying repair to coordinate with 
other maintenance requiring shutdown (and thereby minimizing the total 
number of blowdowns) may be appropriate. PHMSA proposes to require that 
a notification under this paragraph include descriptions of the leak, 
the leaking facility, the leak environment, the proposed extended 
repair schedule, the justification for an extended repair schedule and 
proposed emissions mitigation methods.

Sec.  192.760(i): Recordkeeping

    Proposed Sec.  192.760(i) describes recordkeeping requirements 
associated with leak grading and repair. Beginning on the effective 
date of the rule, PHMSA proposes that records documenting the complete 
history of investigation and grading of each leak prior to completion 
of the repair would need to be retained until five years after the date 
of the final post-repair inspection performed under proposed paragraph 
Sec.  192.760(e). These records include documentation of grading 
monitoring, inspections, upgrades, and downgrades. PHMSA also proposes 
that records associated with the detection, remediation, and repair of 
each leak must be maintained for the life of the pipeline. Permanent 
recordkeeping would apply to both piping and non-piping portions of the 
pipeline. Complete records of the location and timing of leaks and 
repairs is necessary for an adequate leak management program.

Sec.  192.763 Advanced Leak Detection Program

    PHMSA proposes to create Sec.  192.763 that would require operators 
of gas distribution, transmission, offshore gathering, and Types A, B, 
and C gathering pipelines establish a written Advanced Leak Detection 
Program (ALDP) and establish performance standards for both the 
sensitivity of leak detection equipment and for the effectiveness of 
operators' ALDPs. The ALDP represents a comprehensive set of 
technologies and procedures that an operator would use to detect all 
leaks consistent with the proposed ALDP performance standard at Sec.  
192.763(b). PHMSA proposes to require that an operator's written ALDP 
include four main elements: leak detection equipment, leak detection 
procedures, prescribed leakage survey frequencies, and program 
evaluation.
    The first element in an ALDP is the leak detection equipment that 
operators would use to perform leakage surveys, pinpoint leak 
locations, and investigate leaks. These equipment requirements are 
proposed in Sec.  192.763(a)(1). Operator ALDPs would include a list of 
leak detection technologies that the operator would use for leakage 
surveys, pinpointing leak location, and leak investigations. Leak 
detection equipment is not required for surveys of offshore gas 
transmission and offshore gathering pipelines because offshore leaks 
are visibly conspicuous. PHMSA further proposes that any leak detection 
equipment must have a minimum sensitivity of 5 ppm (Sec.  
192.763(a)(1)(ii)) to ensure detection of leaks consistent with the 
proposed ALDP performance standard at Sec.  192.763(b). An operator may 
need to use more sensitive equipment than required by Sec.  
192.763(a)(1)(ii)--or supplemental equipment or techniques (e.g., soap 
bubble testing)--to meet that ALDP performance standard depending on 
the leak detection procedures used and the operating characteristics 
and environment of the pipeline. Alternatively, operators of each of 
(1) natural gas transmission and part 192-regulated gathering 
pipelines, each of which are located either offshore or in Class 1 or 2 
locations, and (2) any gas pipeline transporting flammable, toxic, or 
corrosive gas other than natural gas, may (pursuant to Sec.  
192.763(c)) request use of alternative leak detection equipment by 
submitting a Sec.  192.18 notification for PHMSA review.
    PHMSA proposes to require operators select leak detection equipment 
within their ALDPs based on a documented analysis that reflects the 
state of commercially available advanced leak detection technologies 
and practices, and considers at a minimum the size, configuration, 
operating parameters, and operating environment of the operator's 
system (Sec.  192.763(a)(1)(iii)). PHMSA further proposes an operator's 
analysis consider the appropriateness of specified examples of possible 
advanced leak detection technologies, including each of the following: 
handheld equipment, including optical, infrared, or laser-based 
devices; continuous monitoring via stationary gas detectors, pressure 
monitoring or other means; mobile surveys from vehicle or aerial 
platforms; or systemic use of any other commercially available advanced 
technology capable of meeting the program performance standard in Sec.  
192.763(b).
    The second program element in proposed Sec.  192.763(a)(2) consists 
of the operator's written procedures related to leak detection. PHMSA 
proposes that, at a minimum, the ALDP must include procedures for 
performing compliant leakage surveys for each of the leak detection 
equipment included in an operator's ALDP. To ensure that operators use 
procedures appropriate for environmental conditions such as 
temperature, wind, time of day, precipitation and humidity, the 
operator must define under which conditions the

[[Page 31963]]

procedure may and may not be used. Additionally, those procedures must 
be consistent with any instructions of the leak detection equipment 
manufacturer regarding environmental and operational conditions 
parameters for use.
    PHMSA proposes to require that an operator's procedures must 
provide for pinpointing the location of all leak indications with the 
use of handheld leak detection equipment (Sec.  192.763(a)(2)(ii)). As 
described above, any equipment used for pinpointing leaks must 
generally (for onshore gas transmission, Types A, B, and C gathering, 
and distribution pipelines) have a minimum sensitivity of 5 ppm or 
less. If a leak location was pinpointed with handheld leak detection 
equipment meeting this standard during the initial survey, PHMSA would 
not expect an operator to re-survey the area to meet the requirement of 
this paragraph.
    To ensure the quality of leak detection equipment, PHMSA also 
proposes at Sec.  192.763(a)(2)(iii) to require that an operator have 
procedures for validating that a leak detection device used in its ALDP 
meets the 5-ppm sensitivity requirement in Sec.  192.763(a)(1)(ii) 
prior to initial use. This consists of testing the equipment 
measurements against a known concentration of gas. The operator must 
maintain records that the leak detection equipment has been validated 
for five years after the date that the device ceases to be used in the 
operator's ALDP. Separate from the one-time validation requirement, 
PHMSA also proposes to require that operators have procedures for the 
maintenance and calibration of leak detection equipment (Sec.  
192.763(a)(2)(iv)). At a minimum the operator must follow the 
maintenance and calibration procedures recommended by the equipment 
manufacturer. PHMSA further proposes to require that an operator 
recalibrate leak detection equipment following an indication of 
malfunction.
    The third required element of an ALDP in proposed Sec.  
192.763(a)(3) is the frequency of leakage surveys. As discussed above, 
PHMSA proposes to define minimum leakage survey frequencies in Sec.  
192.723 for gas distribution pipelines and in Sec.  192.706 for gas 
transmission, offshore gathering, and Types A, B, and C gathering 
pipelines. However, PHMSA also proposes that if more frequent leakage 
surveys are necessary to meet the ALDP performance standard in proposed 
Sec.  192.763(b) or otherwise specified by the operator, those 
frequencies must be noted in the operator's ALDP. More frequent leakage 
surveys may be required for less sensitive leak detection equipment, 
challenging survey conditions, or facilities with a high leakage 
frequency.
    The final element of an ALDP consists of proposed requirements in 
Sec.  192.763(a)(4) for operator procedures governing program 
evaluation and improvement. At least annually, operators must re-
evaluate the elements of their ALDP considering, at a minimum, each of 
the following: the performance of leak detection equipment used, 
advances in leak detection technologies and practices, the number of 
leaks initially detected by third parties, the number of leaks and 
incidents overall, and estimated emissions from leaks. This is similar 
in principle to the existing continuous improvement requirements under 
IM requirements in part 192, subparts O and P, as well as requirements 
for certain operators to periodically review procedures under Sec.  
192.605(b)(8) and (c)(4). If an operator finds evidence that their ALDP 
fails to detect leaks during leakage surveys as required by the ALDP 
performance standard at Sec.  192.763(b), it must make changes to 
program elements to ensure that the minimum performance standard in 
Sec.  192.763(b) is met. Operators must consider ways to improve their 
leak detection programs based on leak detection performance data and 
advances in technology.
    PHMSA's proposed ALDP performance standard at Sec.  192.763(b) 
includes a holistic, program-wide performance standard for the ALDP 
elements listed in Sec.  192.763(a). PHMSA proposes to require that an 
ALDP for gas transmission, distribution, offshore gathering, and Types 
A, B, and C gathering pipelines must be capable of detecting all leaks 
that produce a reading of 5 ppm of gas or greater when measured from a 
distance of 5 feet from the pipeline, or from within a wall-to-wall 
paved area. The performance standard of detecting leaks of a size large 
enough to produce a reading of 5 ppm is a measurement of minimum 
detectible leak size rather than the sensitivity of equipment itself. 
PHMSA further proposes that each ALDP must be validated and documented 
with engineering tests and analyses, and that such records should be 
maintained for five years after the date that ALDP is no longer used by 
the operator.
    Lastly, PHMSA proposes at Sec.  192.763(c) the ability for certain 
operators (specifically, each of (1) natural gas transmission, offshore 
gathering, and Types A, B, and C gathering pipelines located in Class 1 
or 2 locations and (2) any gas pipeline transporting flammable, toxic, 
or corrosive gas other than natural gas) to request use of an 
alternative performance standard, pursuant to the notification and 
PHMSA review procedures established in Sec.  192.18. PHMSA proposes to 
require that any notifications submitted under this provision must 
include, among other things, information about the location, design, 
gas being transported, operational parameters, environmental 
conditions, and material properties and history of the pipeline, the 
proposed alternative performance standard, and a description of any 
leak detection equipment and procedures that would be used.

Sec.  192.769 Qualification of Leakage Survey, Investigation, and 
Grading Personnel

    PHMSA proposes to clarify at Sec.  192.769 training and 
qualification requirements for personnel that conduct leakage surveys, 
investigation, and leak grading on gas transmission, distribution, 
offshore gathering, and Types A gathering pipelines. Section 192.769 
proposes to require that all such personnel must be qualified under 
subpart N and have documented work history or training in conducting 
leakage surveys, investigation, and grading. This requirement clarifies 
that surveying, investigating, grading, and repairing leaks are covered 
tasks under subpart N.

Sec.  192.770 Minimizing Emissions From Gas Transmission Pipeline 
Blowdowns

    PHMSA in a new Sec.  192.770 proposes to require gas transmission, 
offshore gathering, and Type A gathering pipeline operators minimize 
the release of gas to the environment from intentional, vented 
emissions (including for repairs, construction, operations, or 
maintenance). PHMSA does not, however, propose to require mitigation 
for emergency releases (e.g., emergency blowdowns) associated with the 
activation of an operator's emergency plan under Sec.  192.615(a)(3). 
However, an operator must document when an emergency release occurs, 
and the justification for not taking mitigative action.
    The proposed regulatory text provides examples of approved 
mitigation methods from which pertinent operators may choose to prevent 
or mitigate vented emissions. The first method is installing and using 
valves or control fittings to reduce the volume of gas that must be 
removed from the pipeline. The second method listed is routing vented 
gas to a flare stack to be ignited or to other equipment for 
consumption. The third, fourth, and fifth methods each involve reducing 
the pressure of a

[[Page 31964]]

pipeline segment prior to venting, reducing total emissions volume. In 
the third example, an operator isolates the pipeline segment upstream 
of the venting segment and uses the downstream compressor station to 
reduce the pressure of the affected segment. The fourth example is 
similar except instead of the compressor station, an operator uses a 
mobile compressor unit to reduce the pressure of the venting segment by 
compressing gas into adjacent facilities or a storage vessel. The fifth 
example is like the fourth, except it may be performed without 
compression. PHMSA also proposes that operators may request, pursuant 
to the notification procedure at Sec.  192.18, use of alternative 
approaches for mitigating vented emissions not listed in the proposed 
regulatory text, but which would provide reduce emissions by at least 
50% compared with venting gas to the atmosphere without mitigative 
action.
    Lastly, PHMSA proposes that operators document the methodology used 
in their procedures, including by documenting an analysis on how its 
selected method minimizes the release of natural gas to the 
environment.

Sec.  192.773 Pressure Relief Device Maintenance and Adjustment of 
Configuration

    PHMSA in a new Sec.  192.773 proposes to require operators of all 
gas distribution, transmission, offshore gathering, and Types A, B, and 
C gathering pipelines to have written operating and maintenance 
procedures for assessment of the proper function of pressure relief 
devices. PHMSA's proposed regulatory text would require operators to 
assess and either repair or replace malfunctioning pressure relief 
devices. PHMSA's proposed language also identifies specific action 
operators would have to take on operation of a malfunctioning pressure 
relief device, to include immediate repair or replacement of relief 
devices that fail to provide adequate overpressure protection. If a 
relief device activates and releases gas below the set pressure ranges 
defined in the operator's operations and maintenance manual, the 
operator must take immediate and continuous action to stop further 
releases of gas and ensure adequate overpressure protection. In the 
latter case, the device must be repaired or replaced as soon as 
practicable but within 30 days of actuation. PHMSA further notes that 
operators would be obliged to maintain records documenting the proper 
operation and any remediation/replacement of pressure relief devices 
for the service life of their facilities.

Sec.  192.1007 What are the required elements of an integrity 
management plan?

    PHMSA proposes to revise Sec.  192.1007(e)(1)(i) and (v) to delete 
existing references to Sec.  192.703(c) that would be rendered 
inapposite by PHMSA's proposed adoption of a different meaning for 
``hazardous leak'' applicable to Sec.  192.703(c) than would be 
applicable within its integrity management regulations at subparts O 
and P.

Sec.  193.2503 Operating Procedures

    Section 193.2503(c) obliges operators of part 193-regulated LNG 
facilities to have and follow written procedures for normal and 
abnormal operations. PHMSA proposes to revise the regulatory language 
in this provision to incorporate within its regulations the section 114 
of the PIPES Act of 2020 self-executing mandate that operators update 
their procedures to provide for the elimination of leaks and minimize 
release of gas from pipeline facilities.

Sec.  193.2523 Minimizing Emissions From Blowdowns and Boiloff

    PHMSA proposes to add a new Sec.  193.2523 to require operators of 
part 193-regulated LNG facilities to mitigate methane emissions from 
non-emergency, vented releases such as blowdowns and tank boiloff. 
PHMSA's proposed mitigation and documentation requirements in Sec.  
193.2523 largely mirror those described in the section V discussion of 
proposed Sec.  192.770.

Sec.  193.2605 Maintenance Procedures

    Section 193.2605(b) obliges operators of part 193-regulated LNG 
facilities to have and follow written maintenance procedures. PHMSA 
proposes to revise the regulatory language in this provision to 
incorporate within its regulations the section 114 of the PIPES Act of 
2020 self-executing mandate that operators update their procedures to 
provide for the elimination of leaks and minimize release of gas from 
pipeline facilities.

Sec.  193.2624 Leakage Surveys

    PHMSA proposes to create a new section requiring operators of LNG 
facilities to perform periodic methane leakage surveys on methane or 
LNG-containing components and equipment at least four times each 
calendar year, with a maximum interval between surveys not to exceed 
4\1/2\ months. This requirement would apply to part 193-regulated LNG 
facilities. The methane leakage surveys would need to be performed with 
leak detection equipment satisfying the 5-ppm minimum sensitivity 
standard proposed for part 192-regulated gas pipelines elsewhere in 
this NPRM. Methane leaks and other conditions discovered during the 
surveys would need to be remediated in accordance with the operators' 
maintenance or abnormal operating conditions procedures, to include any 
repair schedules within those procedures. Leakage survey records, 
including records of equipment validation and calibration, must be 
maintained for 5 years after the leakage survey is completed.

VI. Regulatory Analysis and Notices

A. Legal Authority for This Rulemaking

    This proposed rule is published under the authority of the 
Secretary of Transportation delegated to the PHMSA Administrator 
pursuant to 49 CFR 1.97. Among the statutory authorities delegated to 
PHMSA are those set forth in the Federal Pipeline Safety Statutes (49 
U.S.C. 60101 et seq.) (authorizing, inter alia, issuance of regulations 
governing design, installation, inspection, emergency plans and 
procedures, testing, construction, extension, operation, replacement, 
and maintenance of pipeline facilities) and section 28 of the Mineral 
Leasing Act, as amended (30 U.S.C. 185(w)(3)). For a complete listing 
of authorities, see 49 CFR 1.97.
    This NPRM proposes to implement several provisions of the PIPES Act 
of 2020, including sections 113 (codified at 49 U.S.C. 60102(q)), 114 
(codified at 49 U.S.C. 60108(a)), and 118 (codified at 49 U.S.C. 
60102(b)(5)). While section 113 of the PIPES Act of 2020 does not 
mandate that PHMSA issue leak detection and repair program requirements 
for Type C gas gathering pipelines in Class 1 locations, 49 U.S.C. 
60101(b) and 60102 grant authorities to issue standards for the 
transportation of gas via any part 192-regulated gathering pipelines to 
protect public safety and the environment, which include Type C gas 
gathering pipelines. As explained in section II.E of this NPRM, 
fugitive emissions from all gas gathering pipelines (including Type C 
gas gathering pipelines in Class 1 locations) are a significant source 
of methane emissions which directly harm the environment by 
contributing to climate change--which (as explained in section II.B of 
this NPRM) itself entails public safety and environmental risks. 
Further, as explained in section II.D.3 of this NPRM and discussed in 
further detail in the Preliminary RIA, releases of natural gas 
(particularly unprocessed natural

[[Page 31965]]

gas from Type C and other gas gathering pipelines) contain HAPs and 
VOCs are particularly harmful to public safety and the environment.
    Further, 49 U.S.C. 60117(c) authorizes PHMSA to require owners and 
operators of gas gathering, transmission, and distribution pipelines 
and other pipeline facilities to submit information (including, as 
appropriate, each of annual reports, incident reports, and intentional 
release reports, and NPMS information as proposed in this NPRM) 
required for regulation of those pipeline facilities under the Federal 
Pipeline Safety Statutes. Further, section 60117(c) authorizes the 
Secretary to require owners and operators of Type R gas gathering 
pipelines to submit the same information to support future decision 
making regarding whether and to what extent to impose requirements in 
49 CFR part 192 on those gas gathering pipelines.

B. Executive Order 12866 and DOT Regulatory Policies and Procedures

    E.O. 12866 (``Regulatory Planning and Review''),\296\ as amended by 
E.O. 14094 (``Modernizing Regulatory Review''),\297\ requires that 
agencies ``should assess all costs and benefits of available regulatory 
alternatives, including the alternative of not regulating.'' Agencies 
should consider quantifiable measures and qualitative measures of costs 
and benefits that are difficult to quantify. Further, E.O. 12866 
requires that ``agencies should select those [regulatory] approaches 
that maximize net benefits (including potential economic, 
environmental, public health and safety, and other advantages; 
distributive impacts; and equity), unless a statute requires another 
regulatory approach.'' Similarly, DOT Order 2100.6A (``Rulemaking and 
Guidance Procedures'') requires that regulations issued by PHMSA and 
other DOT Operating Administrations should consider an assessment of 
the potential benefits, costs, and other important impacts of the 
proposed action and should quantify (to the extent practicable) the 
benefits, costs, and any significant distributional impacts, including 
any environmental impacts.
---------------------------------------------------------------------------

    \296\ 58 FR 51735 (Oct. 4, 1993).
    \297\ 88 FR 21879 (April 11, 2023).
---------------------------------------------------------------------------

    E.O. 12866, as amended, and DOT Order 2100.6A require that PHMSA 
submit ``significant regulatory actions'' to the Office of Management 
and Budget (OMB) for review. This action has been determined to be 
significant under E.O. 12866, as amended. It is also considered 
significant under DOT Order 2100.6A because of significant 
congressional, State, industry, and public interest in pipeline safety. 
The proposed rule has been reviewed by OMB in accordance with E.O. 
12866 and is consistent with the requirements of E.O. 12866, as 
amended, and DOT Order 2100.6A.
    E.O. 12866, as amended, and DOT Order 2100.6A also require PHMSA to 
provide a meaningful opportunity for public participation, which 
reinforces requirements for notice and comment in the Administrative 
Procedure Act (APA, 5 U.S.C. 551 et seq.). In accord with the 
requirement, PHMSA seeks public comment on the proposals in the NPRM 
(including preliminary cost and cost savings analyses pertaining to 
those proposals set forth in the preliminary RIA, as well as 
discussions of the public safety, environmental, and equity benefits in 
that document and the draft Environmental Assessment), as well as any 
information that could assist in evaluating the benefits and costs of 
this NPRM.\298\
---------------------------------------------------------------------------

    \298\ PHMSA also participated in OMB-led E.O. 12866 meetings 
requested by public stakeholders during interagency regulatory 
review of this NPRM, including EDF (March 9, 2023), PST (March 17, 
2023), and Boundary Stone Partners/Aclima, Inc. (March 20, 2023). 
Summaries of each E.O. 12866 meeting are available in the rulemaking 
docket at Doc. No. PHMSA-2021-0039.
---------------------------------------------------------------------------

    The quantified benefits of the final rule consist of the climate 
benefits of avoided methane emissions and the market value of avoided 
natural gas losses. PHMSA expects additional, unquantified benefits 
including safety benefits from early detection of leaks before they can 
evolve into incidents and detection of integrity threats on gas 
transmission and gathering pipelines from right-of-way patrols. PHMSA 
also expects additional unquantified environmental and public health 
benefits associated with preventing releases of natural gas, and other 
flammable, toxic or corrosive gases, and expects these benefits to be 
important given the types of health effects resulting from exposure to 
air pollutants (e.g., asthma and other respiratory effects, cancer). 
PHMSA invites commenters to provide additional information that would 
enable quantification of the additional health and safety benefits of 
the rule.
    The table below summarizes the annualized quantified costs and 
benefits for the provisions in the final rule at a 3 percent and a 7 
percent discount rate (discussed in further detail in the Preliminary 
RIA for this NPRM, available in the rulemaking docket):

                                                         Annualized Monetized Costs and Benefits
                                                                     [Million 2020$]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                   Distribution                      Total \1\
                                                                                         ---------------------------------------------------------------
    Discount rate (%)                   Item                 Gathering     Transmission     Lamb et al.    Weller et al.
                                                                                              (2015)          (2020)            Low            High
--------------------------------------------------------------------------------------------------------------------------------------------------------
3                          Benefits.....................            $553             $12            $515          $1,754          $1,081          $2,320
                           Costs........................             211              15             514             654             740             880
                           Net benefits.................             343              -3               1           1,100             341           1,440
7% \2\                     Benefits.....................             549              12             512           1,743           1,073           2,304
                           Costs........................             209              15             530             677             753             900
                           Net benefits.................             340              -3             -18           1,067             320           1,404
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Total costs and benefits are presented as a range to reflect different assumptions regarding leak incidence and methane emissions rate across pipe
  materials. The low estimate reflects distribution costs based on Lamb et al. (2015) whereas the high estimate reflects distribution costs based on
  Weller et al. (2020).
\2\ Costs and benefits of natural gas losses are discounted at 7 percent, whereas climate benefits are based on the average SC-CH4 at 3 percent
  discount. See section 5 of the Preliminary RIA for estimated climate benefits using other discount rates.
Source: PHMSA analysis.

    Benefits of the final rule would depend on, among other things, the 
degree to which compliance actions result in additional safety and gas 
release avoidance and mitigation measures, relative to the baseline, 
and

[[Page 31966]]

the effectiveness of these measures in preventing or mitigating future 
releases or incidents from gas pipeline facilities subject to this 
NPRM.

C. Executive Order 13132: Federalism

    PHMSA analyzed this NPRM in accordance with the principles and 
criteria contained in E.O. 13132 (``Federalism'') \299\ and the 
Presidential Memorandum (''Preemption'') published in the Federal 
Register on May 22, 2009.\300\ E.O. 13132 requires agencies to assure 
meaningful and timely input by State and local officials in the 
development of regulatory policies that may 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.''
---------------------------------------------------------------------------

    \299\ 64 FR 43255 (Aug. 10, 1999).
    \300\ 74 FR 24693 (May 22, 2009).
---------------------------------------------------------------------------

    This NPRM is not expected to have a substantial direct effect on 
State and local governments, the relationship between the National 
Government and the States, or the distribution of power and 
responsibilities among the various levels of government. This NPRM is 
not expected to impose substantial direct compliance costs on State and 
local governments.
    While the NPRM may operate to preempt some State requirements, it 
would not impose any regulation that has substantial direct effects on 
the States, the relationship between the National Government and the 
States, or the distribution of power and responsibilities among the 
various levels of government. Section 60104(c) of Federal Pipeline 
Safety Laws prohibits certain State safety regulation of interstate 
pipelines. Under Federal Pipeline Safety Laws, States that have 
submitted a current certification under section 60105(a) can augment 
Federal pipeline safety requirements for intrastate pipelines regulated 
by PHMSA but may not approve safety requirements less stringent than 
those required by Federal law. A State may also regulate an intrastate 
pipeline facility that PHMSA does not regulate. In this instance, the 
preemptive effect of the regulatory amendments in this NPRM would be 
limited to the minimum level necessary to achieve the objectives of the 
Federal Pipeline Safety Laws. Therefore, the consultation and funding 
requirements of E.O. 13132 do not apply.

D. Regulatory Flexibility Act

    The Regulatory Flexibility Act (5 U.S.C. 601 et seq.) requires 
Federal agencies to conduct an initial Regulatory Flexibility Analysis 
(IRFA) for a proposed rule subject to notice-and-comment rulemaking 
under the APA unless the agency head certifies that the proposed rule 
will not have a significant economic impact on a substantial number of 
small entities. E.O. 13272 (``Proper Consideration of Small Entities in 
Agency Rulemaking'') \301\ obliges agencies to establish procedures 
promoting compliance with the Regulatory Flexibility Act. The DOT posts 
its implementing guidance on a dedicated web page.\302\ This NPRM was 
developed in accordance with E.O. 13272 and DOT guidance to promote 
compliance with the Regulatory Flexibility Act and to ensure that the 
potential impacts of the rulemaking on small entities has been properly 
considered.
---------------------------------------------------------------------------

    \301\ 67 FR 53461 (Aug. 16, 2002).
    \302\ DOT, ``Rulemaking Requirements Related to Small 
Entities,'' https://www.transportation.gov/regulations/rulemaking-requirements-concerning-small-entities (last accessed June 17, 
2021).
---------------------------------------------------------------------------

    PHMSA conducted an IRFA, which has been made available in the 
docket within the Preliminary RIA for this rulemaking. PHMSA has 
preliminarily determined that the proposed rule could result in a 
significant economic impact on a substantial number of small entities, 
depending on the degree to which operators are able to pass-through 
costs. PHMSA seeks comment on whether the proposed rule, if adopted, 
would have a significant economic impact on a significant number of 
small entities.

E. National Environmental Policy Act

    The National Environmental Policy Act (NEPA, 42 U.S.C. 4321 et. 
seq.) requires Federal agencies to consider the consequences of major 
Federal actions and prepare a detailed statement on actions 
significantly affecting the quality of the human environment. The 
Council on Environmental Quality implementing regulations (40 CFR parts 
1500-1508) require Federal agencies to conduct an environmental review 
considering (1) the need for the action, (2) alternatives to the 
action, (3) probable environmental impacts of the action and 
alternatives, and (4) the agencies and persons consulted during the 
consideration process. DOT Order 5610.1C (``Procedures for Considering 
Environmental Impacts'') establishes departmental procedures for 
evaluation of environmental impacts under NEPA and its implementing 
regulations.
    PHMSA analyzed this NPRM in accordance with NEPA, NEPA implementing 
regulations, and DOT Order 5610.1C. PHMSA has prepared a draft 
environmental assessment (DEA) and preliminarily determined this action 
will not significantly affect the quality of the human environment. To 
the extent that the NPRM has impacts on the environment, these are 
primarily beneficial ecological and human health impacts from early 
detection of gas leaks and minimizing emissions of methane, a powerful 
GHG that contributes to climate change. A copy of the draft EA for this 
action is available in the docket. PHMSA invites comment on the 
environmental impacts of this NPRM.

F. Environmental Justice

    E.O. 12898 (``Federal Actions to Address Environmental Justice in 
Minority Populations and Low-Income Populations''),\303\ as 
supplemented by the E.O. entitled ``Revitalizing Our Nation's 
Commitment to Environmental Justice for All'' (April 21, 2023),\304\ 
directs Federal agencies to take appropriate and necessary steps to 
identify and address disproportionately high and adverse effects of 
Federal actions on the health or environment of minority and low-income 
populations ``[t]o the greatest extent practicable and permitted by 
law.'' DOT Order 5610.2C (``U.S. Department of Transportation Actions 
to Address Environmental Justice in Minority Populations and Low-Income 
Populations'') establishes departmental procedures for effectuating 
E.O. 12898 promoting the principles of environmental justice through 
full consideration of environmental justice principles throughout 
planning and decision-making processes in the development of programs, 
policies, and activities, including PHMSA rulemaking.
---------------------------------------------------------------------------

    \303\ 59 FR 7629 (Feb. 16, 1994).
    \304\ E.O. number and Federal Register citation forthcoming. See 
White House, ``Executive Order on Revitalizing Our Nation's 
Commitment to Environmental Justice for All'' (April 21, 2023), 
https://www.whitehouse.gov/briefing-room/presidential-actions/2023/
04/21/executive-order-on-revitalizing-our-nations-commitment-to-
environmental-justice-for-all/
#:~:text=We%20must%20advance%20environmental%20justice,human%20health
%20and%20the%20environment.
---------------------------------------------------------------------------

    PHMSA has evaluated this NPRM under DOT Order 5610.2C and E.O. 
12898 and has preliminarily determined it will not cause 
disproportionately high and adverse human health and environmental 
effects on minority and low-income populations. The NPRM is facially 
neutral and national in scope; it is neither directed toward a 
particular population, region, or community, nor

[[Page 31967]]

is it expected to adversely impact any particular population, region, 
or community. And insofar as PHMSA expects the rulemaking would reduce 
the safety and environmental risks associated with gas gathering, 
transmission, and distribution lines, many of which are located in the 
vicinity of environmental justice communities,\305\ PHMSA does not 
expect the regulatory amendments introduced by this final rule would 
entail disproportionately high adverse risks for minority or low-income 
populations in the vicinity of those pipelines. Lastly, as explained in 
the draft environmental assessment, PHMSA expects that its proposed 
regulatory amendments will yield GHG emissions reductions, thereby 
reducing the risks posed by anthropogenic climate change to minority 
and low-income populations.
---------------------------------------------------------------------------

    \305\ See Ryan Emmanuel, et al., ``Natural Gas Gathering and 
Transmission Pipelines and Social Vulnerability in the United 
States,'' 5:6 GeoHealth (June 2021), https://agupubs.onlinelibrary.wiley.com/toc/24711403/2021/5/6 (concluding 
that natural gas gathering and transmission infrastructure is 
disproportionately sited in socially-vulnerable communities).
---------------------------------------------------------------------------

G. Executive Order 13175: Consultation and Coordination With Indian 
Tribal Governments

    PHMSA analyzed this NPRM according to the principles and criteria 
in E.O. 13175 (``Consultation and Coordination with Indian Tribal 
Governments'') \306\ and DOT Order 5301.1 (``Department of 
Transportation Programs, Polices, and Procedures Affecting American 
Indians, Alaska Natives, and Tribes''). E.O. 13175 requires agencies to 
assure meaningful and timely input from Tribal government 
representatives in the development of rules that significantly or 
uniquely affect Tribal communities by imposing ``substantial direct 
compliance costs'' or ``substantial direct effects'' on such 
communities or the relationship and distribution of power between the 
Federal Government and Tribes.
---------------------------------------------------------------------------

    \306\ 65 FR 67249 (Nov. 9, 2000).
---------------------------------------------------------------------------

    PHMSA assessed the impact of the NPRM and has preliminarily 
determined that it will not significantly or uniquely affect Tribal 
communities or Indian Tribal governments. The rulemaking's regulatory 
amendments are facially neutral and would have broad, national scope; 
PHMSA, therefore, does not expect this NPRM to significantly or 
uniquely affect Tribal communities, much less impose substantial 
compliance costs on Native American Tribal governments or mandate 
Tribal action. Insofar as PHMSA expects the rulemaking will improve 
safety and reduce public safety and environmental risks associated with 
gas pipelines, PHMSA believes it will not entail disproportionately 
high adverse risks for Tribal communities. While PHMSA is not aware of 
specific Tribal-owned business entities that operate part 192-regulated 
gas pipelines, any such business entities could be subject to direct 
compliance costs as a result of this proposed rule. Because PHMSA does 
not anticipate that this proposed rule would have tribal implications, 
the funding and consultation requirements of E.O. 13175 would not 
apply. PHMSA seeks comment on the applicability of E.O. 13175 to this 
proposed rule and the existence of any Tribal-owned business entities 
operating pipelines affected by the proposed rule (along with the 
extent of such potential impacts).

H. Executive Order 13211

    E.O. 13211 (``Actions Concerning Regulations That Significantly 
Affect Energy Supply, Distribution, or Use'') \307\ requires Federal 
agencies to prepare a Statement of Energy Effects for any ``significant 
energy action.'' E.O. 13211 defines a ``significant energy action'' is 
defined as any action by an agency (normally published in the Federal 
Register) that promulgates, or is expected to lead to the promulgation 
of, a final rule or regulation (including a notice of inquiry, ANPRM, 
and NPRM) that (1)(i) is a significant regulatory action under E.O. 
12866 or any successor order and (ii) is likely to have a significant 
adverse effect on the supply, distribution, or use of energy; or (2) is 
designated by the Administrator of the Office of Information and 
Regulatory Affairs as a significant energy action.
---------------------------------------------------------------------------

    \307\ 66 FR 28355 (May 22, 2001).
---------------------------------------------------------------------------

    This NPRM is a significant action under E.O. 12866, as amended; 
however, it is not likely to have a significant adverse effect on 
supply, distribution, or energy use, as further discussed in the 
Preliminary RIA. Further, OIRA has not designated this NPRM as a 
significant energy action.

I. Paperwork Reduction Act

    Pursuant to 5 CFR 1320.8(d), PHMSA is required to provide 
interested members of the public and affected agencies with an 
opportunity to comment on information collection and recordkeeping 
requests. The proposals in the Pipeline Safety: Gas Pipeline Leak 
Detection and Repair NPRM would trigger new reporting and notification 
requirements for operators of natural gas transmission, distribution, 
and gathering pipelines. PHMSA proposes new and revised reporting 
requirements intended to improve the quality of the data available 
concerning pipeline leaks and other sources of emissions.
Reporting Releases of Gas
    PHMSA proposes to require pipeline operators to submit data on 
intentional and unintentional releases of gas with a volume of 1 MMCF 
or greater excluding certain events that had been reported as incidents 
under Sec. Sec.  191.9 or 191.15. To collect this data, PHMSA proposes 
the creation of a new large-volume emissions report to parallel 
existing incident reporting requirements. Operators would be required 
to submit this data upon each occurrence of a release that meets the 
reporting requirement within 30 days from the date of detection or 30 
days from the date that a previously detected release became 
reportable. These new large-volume gas release reports would provide 
valuable information on the primary sources and causes of vented 
emissions and the causes of large-volume leaks that do not qualify as 
incidents. This data would address information gaps in the current 
incident reporting requirements with respect to intentional releases 
and environmentally hazardous unintentional releases with release 
volumes between 1 MMCF and 3 MMCF. PHMSA estimates that it would 
receive 373 reports on average each year (239 and 134 reports for 
gathering and transmission, respectively), with each report estimated 
to require 4 hours to prepare.
Annual Report Revisions
    PHMSA also proposes revisions to the existing gas transmission, 
gathering, and distribution annual report forms to include reporting of 
leaks discovered and repaired by grade, estimated leak emissions by 
grade, and estimated annual emissions from other sources by source 
category. Currently, these forms include data on leak repair, however 
they lack data on leaks discovered and data on emissions generally.
Safety-Related Condition Reporting
    PHMSA proposes an exception from Sec.  191.23 safety-related 
condition reporting requirements for events that are reported as large-
volume gas releases. The proposed exception for large-volume incident 
reports would be consistent with the existing exception at Sec.  
191.23(b) for events reported as incidents. Because large-volume gas 
release reports would have roughly equivalent detail to an incident 
report,

[[Page 31968]]

a less detailed safety-related condition report would not be necessary. 
PHMSA expects the burden for this information collection to decrease 
because of this change.
National Pipeline Mapping System Reporting
    This NPRM proposes to extend the reporting requirements at Sec.  
191.29 for the NPMS to offshore gathering pipelines as well as Types A, 
B, and C regulated onshore gas gathering pipelines. Currently only gas 
transmission pipelines are required to provide geospatial data on their 
pipeline systems in accordance with the NPMS requirements at 49 U.S.C. 
60132 and 49 CFR 191.29. The collection of geospatial data from gas 
gathering pipelines would provide PHMSA critical knowledge about the 
location and operating characteristics of these pipelines to assist in 
the identification and remediation of leaks.
Notification Requirements
    PHMSA requires operators to make notifications in accordance with 
Sec.  192.18 90 days in advance of using an alternative technology or 
assessment method. Operators may proceed only if they do not receive a 
letter objecting to the proposed use of other technology and/or 
methods.
    PHMSA proposes, in Sec.  192.706(a), to allow operators to request 
the use of human senses, in lieu of leak detection equipment, when 
conducting a leak survey if the operator provides advance notification 
to PHMSA in accordance with Sec.  192.18.
    In Sec.  192.763(c), PHMSA proposes to allow operators to request 
to use an alternative advanced leak detection performance standard if 
the operator notifies PHMSA, in accordance with Sec.  192.18. For gas 
transmission, offshore gathering, and Types A, B, and C gathering 
pipelines located in Class 1 or Class 2 locations, an operator may use 
an alternative performance standard with prior notification to, and 
review by PHMSA in accordance with Sec.  192.18. The notification must 
include: mileage by system type, known material properties, location, 
HCAs, operating parameters, environmental conditions, leak history, and 
design specifications, including coating, cathodic protection status, 
and pipe welding or joining method, the proposed performance standard, 
any safety conditions such as increased survey frequency, the leak 
detection equipment, procedures, and leakage survey frequencies the 
operator proposes to employ, data on the sensitivity and the leak 
detection performance of the proposed alternative ALDP standard, and 
the gas transported by the pipeline.
    In this proposed rule, an operator may request an extension of the 
leak repair deadline requirements for an individual grade 3 leak with 
advance notification to, and review by, PHMSA pursuant to Sec.  192.18. 
The operator's notification must show that the delayed repair timeline 
would not result in an increased risk to public safety, as well as that 
either the required repair deadline is impracticable, or that 
remediation within the specified time frame would result in the release 
of more gas to the environment than would occur with continued 
monitoring. The notification must include: a description of the leaking 
facility including the location, material properties, the type of 
equipment that is leaking, and the operating pressure; a description of 
the leak and the leak environment, including gas concentration 
readings, leak rate if known, class location, nearby buildings, weather 
conditions, soil conditions, and other conditions that could affect gas 
migration, such as pavement; a description of the alternative repair 
schedule and a justification for the same; and proposed emissions 
mitigation methods and monitoring and repair schedule. PHMSA estimates 
that it may receive 508 requests to extend the deadline for remedying 
leaks on average per year (341 from gas gathering operators and 167 
from gas transmission operators), and that each of these requests would 
require approximately 8 hours to prepare.
Recordkeeping Requirements
    PHMSA proposes to require operators to develop and maintain various 
records in conjunction with the proposed requirements in this NPRM. 
Among those requirements, operators must develop written procedures for 
grading and repairing leaks according to Sec.  192.760(a)(1); operators 
must document post-repair evaluations according to Sec.  192.760(e); 
operators must record the history of each leak, including leak 
discovery, grading, monitoring, remediation, upgrades, and downgrades, 
and maintain these records for a period of 5 years (records of repairs 
must be maintained for the life of the pipeline) pursuant to Sec.  
192.760(i)(1) and (2); operators must document the leak detection 
equipment choice analysis required in Sec.  192.763(f); operators must 
also record leak detection equipment calibration (and re-calibration) 
and maintain these records for the life of the equipment pursuant to 
Sec.  192.763(h)(2); and operators must record the repair or 
replacement of a pressure relief device and maintain these records for 
the life of the pipeline according to Sec.  192.773(c). PHMSA estimates 
that it would take operators, on average, 80 hours annually to develop 
these records. PHMSA estimates that it would take operators 20 hours 
annually to maintain these records. This burden would be incurred by 
the total reporting community.
    PHMSA will submit the following information collection requests to 
OMB for approval based on the requirements in this proposed rule. These 
information collections are contained in the pipeline safety 
regulations, 49 CFR parts 190 through 199. The following information is 
provided for each information collection: (1) Title of the information 
collection; (2) OMB control number; (3) Current expiration date; (4) 
Type of request; (5) Abstract of the information collection activity; 
(6) Description of affected public; (7) Estimate of total annual 
reporting and recordkeeping burden; and (8) Frequency of collection. 
The information collection burden for the following information 
collections are estimated to be revised as follows:
    1. Title: Incident and Annual Reports for Gas Pipeline Operators.
    OMB Control Number: 2137-0522.
    Current Expiration Date: 03/31/2025.
    Abstract: This mandatory information collection covers the 
collection of data from operators of natural gas pipelines, UNGSFs, and 
LNG facilities for annual reports. 49 CFR 191.17 requires operators of 
UNGSFs, gas transmission systems, and gas gathering systems to submit 
an annual report by March 15, for the preceding calendar year. This 
information collection also covers the collection of immediate notice 
of incident report data from Gas pipeline operators.
    PHMSA proposes to revise this information collection in conjunction 
with proposed regulatory changes made in the Pipeline Safety: Gas 
Pipeline Leak Detection and Repair NPRM. The requested revision would 
revise form F7100.2-1, the ``Natural and Other Gas Transmission and 
Gathering Pipeline Systems Annual Report'' form, to collect the total 
number of leaks identified within a calendar year.
    PHMSA currently estimates that 1,810 operators spend, on average, 
47 hours completing form PHMSA F7100.2-1. PHMSA expects these operators 
to spend an additional 6 hours reporting the newly requested data on 
the total number of leaks identified and estimated emissions within the 
calendar year. This would increase the burden, per operator, from 47.5 
hours annually to 53.5 hours annually to complete form PHMSA F7100.2-1. 
This revision would

[[Page 31969]]

result in an additional reporting burden of 10,860 hours annually 
bringing the overall burden for completing form F7100.2-1 to 96,835 
hours (53.5 hours x 1,810 responses).
    Affected Public: All gas pipeline operators.
    Annual Reporting and Recordkeeping Burden:
    Total Annual Responses: 3,321.
    Total Annual Burden Hours: 106,671 hours.
    Frequency of Collection: Annual.
    2. Title: Annual Report for Gas Distribution Operators.
    OMB Control Number: 2137-0629.
    Current Expiration Date: 05/31/2024.
    Abstract: This information collection request would require 
operators of gas distribution pipeline systems to submit annual report 
data to the Office of Pipeline Safety in accordance with the 
regulations stipulated in 49 CFR part 191 by way of form PHMSA F 
7100.1-1. The form is to be submitted once for each calendar year. The 
annual report form collects data about the pipe material, size, and 
age. The form also collects data on leaks from these systems as well as 
excavation damages. PHMSA uses the information to track the extent of 
gas distribution systems and normalize incident and leak rates. PHMSA 
proposes to revise this information collection in conjunction with 
proposed regulatory changes made in the Pipeline Safety: Gas Pipeline 
Leak Detection and Repair NPRM. The requested revision would revise 
form PHMSA F7100.1-1, the Gas Distribution Annual Report, to collect 
the total number of leaks identified within a calendar year, emissions 
from leaks by grade, and estimated emissions from other sources by 
source categories.
    PHMSA estimates that, currently, 1,446 operators spend 17.5 hours 
completing the Gas Distribution Annual report each year. PHMSA expects 
these operators to spend an additional 6 hours reporting the newly 
requested data on the total number of leaks identified and estimated 
emissions within the calendar year. Because of this, PHMSA expects the 
burden for completing form PHMSA F7100.1-1 to increase to 23.5 (17.5+6) 
hours per report adding a total of 8,676 (6 hours x 1,446 operators) 
hours to the overall burden for this information collection.
    Affected Public: Gas Distribution operators.
    Annual Reporting and Recordkeeping Burden:
    Total Annual Responses: 1,446.
    Total Annual Burden Hours: 33,981.
    Frequency of Collection: Annual.
    3. Title: Reporting Safety-Related Conditions on Gas, Hazardous 
Liquid, and Carbon Dioxide Pipelines and Liquefied Natural Gas 
Facilities.
    OMB Control Number: 2137-0578.
    Current Expiration Date: 01/31/2023.
    Abstract: 9 U.S.C. 60102 requires each operator of a pipeline 
facility (except master meter operators) to submit to DOT a written 
report on any safety-related condition that causes or has caused a 
significant change or restriction in the operation of a pipeline 
facility or a condition that is a hazard to life, property, or the 
environment. PHMSA proposes to adjust the burden associated with this 
information collection in conjunction with proposed regulatory changes 
made in the Pipeline Safety: Gas Pipeline Leak Detection and Repair 
NPRM which exempts large-volume gas releases from safety-related 
condition reporting. The requested revision would reduce the burden for 
this information collection by 3 responses and 18 burden hours 
annually. PHMSA is not proposing to collect any additional data at this 
time.
    Affected Public: All gas pipeline operators.
    Annual Reporting and Recordkeeping Burden:
    Total Annual Responses: 171.
    Total Annual Burden Hours: 1,026.
    Frequency of Collection: Annual.
    4. Title: Incident and Annual Reports for Gas Pipeline Operators.
    OMB Control Number: 2137-0635.
    Current Expiration Date: 01/31/2023.
    Abstract: Operators of natural gas pipelines and LNG facilities are 
required to report incidents, on occasion, to PHMSA per the 
requirements in 49 CFR part 191. This mandatory information collection 
covers the collection of incident report data from natural gas pipeline 
operators. The reports contained within this information collection 
support the Department of Transportation's strategic goal of safety. 
This information is an essential part of PHMSA's overall effort to 
minimize natural gas transmission, gathering, and distribution pipeline 
failures. PHMSA proposes to revise this information in conjunction with 
proposed regulatory changes made in the Pipeline Safety: Gas Pipeline 
Leak Detection and Repair NPRM to include a new form, (PHMSA F 7100.5) 
designed to collect data on intentional and unintentional releases of 
gas with a volume of 1 MMCF or greater.
    PHMSA estimates that it would receive 593 of these new reports on 
average each year (139 gas transmission, 254 gas gathering, and 200 gas 
distribution), with each report estimated to require 12 hours to 
prepare. This would result in an additional 593 responses and 7,116 
burden hours for this information collection.
    Affected Public: All gas pipeline operators.
    Annual Reporting and Recordkeeping Burden:
    Total Annual Responses: 1,592.
    Total Annual Burden Hours: 11,572.
    Frequency of Collection: On Occasion.
    5. Title: National Pipeline Mapping System Program.
    OMB Control Number: 2137-0596.
    Expiration Date: 1/31/2023.
    Type of Request: Revision of a previously approved information 
collection.
    Abstract: The Pipeline Safety Improvement Act of 2002 (Pub. L. 107-
355), 49 U.S.C. 60132, ``National Pipeline Mapping System,'' requires 
the operator of a pipeline facility (except distribution lines and 
gathering lines) to provide information to PHMSA. Each operator is 
required to submit geospatial data appropriate for use in the NPMS or 
data in a format that can be readily converted to geospatial data; the 
name and address of the person with primary operational control (to be 
known as its operator), and a means for a member of the public to 
contact the operator for additional information about the pipeline 
facilities it operates. Operators would submit the requested data 
elements once and make annual updates to the data if necessary. These 
data elements strengthen the effectiveness of PHMSA's risk rankings and 
evaluations, which are used as a factor in determining pipeline 
inspection priority and frequency; allow for more effective assistance 
to emergency responders by providing them with a more reliable, 
complete data set of pipelines and facilities; and provide better 
support to PHMSA's inspectors by providing more accurate pipeline 
locations and additional pipeline-related geospatial data that can be 
linked to tabular data in PHMSA's inspection database.
    PHMSA proposes to revise this information in conjunction with 
proposed regulatory changes made in the Pipeline Safety: Gas Pipeline 
Leak Detection and Repair NPRM to require gas gathering operators to be 
subject to NPMS reporting. PHMSA estimates that gas transmission 
operators currently spend approximately 120 hours each year submitting 
geospatial data through the NPMS. PHMSA estimates that, due to the 
changes in this NPRM, 378 Type A, B, and C operators would be added to 
the NPMS reporting community. This addition would increase the number 
of responses for this information collection by 378 and increase the 
overall reporting burden by 45,360 hours.

[[Page 31970]]

    Respondents: Operators of gas transmission, hazardous liquid, or 
LNG pipeline facilities.
    Annual Reporting and Recordkeeping Burden:
    Estimated Number of Responses: 1,724 responses.
    Estimated Total Annual Burden: 207,761 hours.
    Frequency of Collection: Annually.
    6. Title: Notification Requirements for Leak Detection and Repair.
    OMB Control Number: PHMSA will request a new OMB Control No.
    Current Expiration Date: TBD.
    Abstract: A person owning or operating a natural gas pipeline 
facility is required to provide information to the Secretary of 
Transportation at the Secretary's request according to 49 U.S.C. 60117. 
The Pipeline Safety regulations contained within 49 CFR part 192 
require operators to make various notifications upon the occurrence of 
certain events. The provisions covered under this ICR involve 
notification requirements for operators who utilize alternative or 
expanded technologies and methods when conducting leak detection and 
repair activities. These notification requirements are necessary to 
ensure safe operation of pipelines and ascertain compliance with gas 
pipeline safety regulations. These mandatory notifications help PHMSA 
to stay abreast of issues related to the health and safety of the 
nation's pipeline infrastructure.
    PHMSA proposes to create this information in conjunction with 
proposed regulatory changes made in the Pipeline Safety: Gas Pipeline 
Leak Detection and Repair NPRM which requires operators to notify PHMSA 
in various instances pertaining to leak detection and repair 
activities. PHMSA expects all gas pipeline operators to be subject to 
these notification requirements. PHMSA estimates that it may receive 
1,000 requests on average per year from gas distribution operators to 
extend the deadline for remedying leaks, with each of these requests 
requiring approximately 8 hours to prepare.
    Affected Public: All gas pipeline operators.
    Annual Reporting and Recordkeeping Burden:
    Total Annual Responses: 1,000.
    Total Annual Burden Hours: 8,000.
    Frequency of Collection: On Occasion.
    7. Title: Recordkeeping Requirements for Gas Pipeline Operators.
    OMB Control Number: 2137-0049.
    Current Expiration Date: 3/31/2025.
    Abstract: A person owning or operating a natural gas pipeline 
facility is required to maintain records, make reports, and provide 
information to the Secretary of Transportation at the Secretary's 
request. This mandatory information collection request would require 
owners and/or operators of gas pipeline systems to make and maintain 
records in accordance with the requirements prescribed in 49 CFR part 
192 and to provide information to the Secretary of Transportation at 
the Secretary's request. Certain records are maintained for a specific 
length of time while others are required to be maintained for the life 
of the pipeline. PHMSA uses these records to verify compliance with 
regulated safety standards and to inform the agency on possible safety 
risks.
    PHMSA proposes to revise this information in conjunction with 
proposed regulatory changes made in the Pipeline Safety: Gas Pipeline 
Leak Detection and Repair NPRM which includes various recordkeeping 
requirements for operators pertaining to leak detection and remediation 
activities.
    Affected Public: All gas pipeline operators.
    Annual Reporting and Recordkeeping Burden:
    Total Annual Responses: 3,867,101 responses.
    Total Annual Burden Hours: 1,904,157 hours.
    Frequency of Collection: On Occasion.
    Requests for copies of these information collections should be 
directed to Angela Hill at [email protected]. Comments are invited 
on:
    (a) The need for the proposed collection of information for the 
proper performance of the functions of the agency, including whether 
the information will have practical utility;
    (b) The accuracy of the agency's estimate of the burden of the 
revised collection of information, including the validity of the 
methodology and assumptions used;
    (c) Ways to enhance the quality, utility, and clarity of the 
information to be collected; and
    (d) Ways to minimize the burden of the collection of information on 
those who are to respond, including the use of appropriate automated, 
electronic, mechanical, or other technological collection techniques.
    Send comments directly to the Office of Management and Budget, 
Office of Information and Regulatory Affairs, Attn: Desk Officer for 
the Department of Transportation, 725 17th Street NW, Washington, DC 
20503. Comments should be submitted on or prior to July 17, 2023.

J. Unfunded Mandates Reform Act of 1995

    The Unfunded Mandates Reform Act (UMRA, 2 U.S.C. 1501 et seq.) 
requires agencies to assess the effects of Federal regulatory actions 
on State, local, and Tribal governments, and the private sector. For 
any NPRM or final rule that includes a Federal mandate that may result 
in the expenditure by state, local, and Tribal governments, in the 
aggregate of $100 million or more (in 1996 dollars) in any given year, 
the agency must prepare, amongst other things, a written statement that 
qualitatively and quantitatively assesses the costs and benefits of the 
Federal mandate.
    PHMSA expects this NPRM would impose compliance costs of $100 
million or more (in 1996 dollars) on private sector entities. PHMSA has 
conducted an assessment (within the Preliminary RIA in the rulemaking 
docket) of the NPRM and has preliminarily concluded that the NPRM's 
proposed regulatory amendments will yield an appropriate balancing of 
costs and benefits.

K. Privacy Act Statement

    In accordance with 5 U.S.C. 553(c), PHMSA solicits comments from 
the public to better inform its rulemaking process. PHMSA posts these 
comments, without edit, including any personal information the 
commenter provides, to www.regulations.gov, as described in the system 
of records notice (DOT/ALL-14 FDMS), which can be reviewed at 
www.dot.gov/privacy.

L. Executive Order 13609 and International Trade Analysis

    E.O. 13609 (``Promoting International Regulatory Cooperation'') 
\308\ requires agencies consider whether the impacts associated with 
significant variations between domestic and international regulatory 
approaches are unnecessary or may impair the ability of American 
business to export and compete internationally. In meeting shared 
challenges involving health, safety, labor, security, environmental, 
and other issues, international regulatory cooperation can identify 
approaches that are at least as protective as those that are or would 
be adopted in the absence of such cooperation. International regulatory 
cooperation can also reduce, eliminate, or prevent unnecessary 
differences in regulatory requirements.
---------------------------------------------------------------------------

    \308\ 77 FR 26413 (May 4, 2012).
---------------------------------------------------------------------------

    Similarly, the Trade Agreements Act of 1979 (Pub. L. 96-39), as 
amended by the Uruguay Round Agreements Act (Pub. L. 103-465), 
prohibits Federal

[[Page 31971]]

agencies from establishing any standards or engaging in related 
activities that create unnecessary obstacles to the foreign commerce of 
the United States. For purposes of these requirements, Federal agencies 
may participate in the establishment of international standards, so 
long as the standards have a legitimate domestic objective, such as 
providing for safety, and do not operate to exclude imports that meet 
this objective. The statute also requires consideration of 
international standards and, where appropriate, that they be the basis 
for U.S. standards.
    PHMSA engages with international standards setting bodies to 
protect the safety of the American public. PHMSA has assessed the 
effects of the NPRM and has preliminarily determined that its proposed 
regulatory amendments would not cause unnecessary obstacles to foreign 
trade.

M. Cybersecurity and Executive Order 14082

    E.O. 14082 (``Improving the Nation's Cybersecurity'') \309\ 
expressed the Administration policy that ``the prevention, detection, 
assessment, and remediation of cyber incidents is a top priority and 
essential to national and economic security.'' E.O. 14082 directed the 
Federal Government to improve its efforts to identify, deter, and 
respond to ``persistent and increasingly sophisticated malicious cyber 
campaigns.'' In keeping with these policies and directives, PHMSA has 
assessed the effects of this NPRM to determine what impact the proposed 
regulatory amendments may have on cybersecurity risks for pipeline 
facilities.
---------------------------------------------------------------------------

    \309\ 86 FR 26633 (May 17, 2021).
---------------------------------------------------------------------------

    PHMSA's proposed requirements would not require pipeline operators 
to generate new security-sensitive records. Most of the pipeline 
facilities for which PHMSA proposes leak detection and repair 
requirements (and associated recordkeeping requirements) are already 
subject to such requirements--this NPRM simply proposes to enhance and 
expand those requirements. While computerized continuous or remote 
monitoring systems for pipeline facilities could be more vulnerable to 
cyber-attack than other technologies, the NPRM does not prescribe the 
use of any particular leak detection technology within operator 
advanced leak detection programs. PHMSA proposes to require operators 
to evaluate remote and real-time leak detection technologies as one 
potential approach when operators are designing the portfolio of 
technologies to be used to satisfy the proposed ALDP requirements, but 
ultimately operators can choose to adopt or decline such technologies.
    One proposal that may present relatively more cybersecurity risk is 
the proposed requirement for offshore gas gathering pipelines and Types 
A, B, and C gas gathering pipelines to provide geospatial data for 
NPMS. If hacked by a bad actor, this information could provide 
particularly sensitive information regarding the location of gas 
gathering infrastructure nationwide. However, the risk associated with 
hacking of NPMS data on gas gathering infrastructure appears relatively 
low compared to the risks associated with unauthorized release of NPMS 
data on gas transmission infrastructure. Data on gas transmission 
infrastructure has long been stored in NPMS and would likely be 
considered a more attractive target for bad actors given the greater 
importance of transmission lines in the U.S. interstate gas supply 
network.
    Operators affected by these proposed requirements may also be 
subject to cybersecurity requirements and guidance under Transportation 
Security Administration (TSA) Security Directives,\310\ as well as any 
new requirements resulting from ongoing TSA efforts to strengthen 
cybersecurity and resiliency in the pipeline sector, as discussed 
within an advance notice of proposed rulemaking published in November 
2022.\311\ The Cybersecurity & Infrastructure Security Agency (CISA) 
and the Pipeline Cybersecurity Initiative (PCI) of the U.S. Department 
of Homeland Security also conduct ongoing activities to address 
cybersecurity risks to U.S. pipeline infrastructure and may introduce 
other cybersecurity requirements and guidance for gas pipeline 
operators.\312\
---------------------------------------------------------------------------

    \310\ E.g., TSA, ``Ratification of Security Directive,'' 86 FR 
38209 (July 20, 2021) (ratifying TSA Security Directive Pipeline-
2012-01, which requires certain pipeline owners and operators to 
conduct actions to enhance pipeline cybersecurity).
    \311\ TSA, ``Enhancing Surface Cyber Risk Management,'' 87 FR 
74702 (Nov. 30, 2022).
    \312\ See, e.g., CISA, National Cyber Awareness System Alerts, 
https://www.cisa.gov/uscert/ncas/alerts (last accessed Feb. 1, 
2023).
---------------------------------------------------------------------------

    PHMSA has considered the effects of the NPRM and has preliminarily 
determined that its proposed regulatory amendments would not materially 
affect the cybersecurity risk profile for pipeline facilities within 
the scope of the proposed amendments. PHMSA seeks comment on any other 
potential cybersecurity impacts of the proposed amendments beyond the 
considerations discussed here.

N. Severability

    The purpose of this proposed rule is to operate holistically in 
addressing a panoply of issues related to safety and environmental 
hazards on regulated pipelines, with a focus on detection, grading, and 
repair of leaks. However, PHMSA recognizes that certain provisions 
focus on unique topics. Therefore, PHMSA preliminarily finds that the 
various provisions of this proposed rule are severable and able to 
function independently if severed from each other, and thus, in the 
event a court were to invalidate one or more of this proposed rule's 
unique provisions, the remaining provisions should stand and continue 
in effect. PHMSA seeks comment on which portions of this proposed rule 
should or should not be severable.

List of Subjects

49 CFR Part 191

    Natural gas, Pipeline safety, Reporting and recordkeeping 
requirements.

49 CFR Part 192

    Natural gas, Pipeline safety, Safety.

49 CFR Part 193

    Pipeline safety, Reporting and recordkeeping requirements.

    In consideration of the foregoing, PHMSA proposes to amend 49 CFR 
parts 191, 192, and 193 as follows:

PART 191--TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE; 
ANNUAL, INCIDENT, AND OTHER REPORTING

0
1. The authority citation for part 191 continues to read as follows:

    Authority:  30 U.S.C. 185(w)(3), 49 U.S.C. 5121, 60101 et. seq., 
and 49 CFR 1.97.

0
2. In Sec.  191.3:
0
a. Revise paragraph (1)(ii) in the definition of ``Incident''; and
0
b. Add the definition of ``Large-volume gas release'' in alphabetical 
order.
    The revision and addition read as follows:

Sec.  191.3  Definitions.

* * * * *

Incident * * *

    (1) * * *
    (ii) Estimated property damage of $122,000 or more, including loss 
to the operator and others, or both, but excluding each of the cost of 
gas lost, the cost to acquire permits, and the cost to remove and 
replace non-operator infrastructure that was not damaged by the 
release. For adjustments for inflation

[[Page 31972]]

observed in calendar year 2021 onwards, changes to the reporting 
threshold will be posted on PHMSA's website. These changes will be 
determined in accordance with the procedures in appendix A to part 191.
* * * * *
    Large-volume gas release means an intentional or unintentional 
release of 1 million cubic feet or more of gas from a gas pipeline 
facility as that term is defined in Sec.  192.3.
* * * * *
0
3. Add Sec.  191.19 to read as follows:

Sec.  191.19  Large-volume gas release report.

    Each operator of a gas pipeline facility must report a large-volume 
gas release on DOT Form PHMSA-F7100.5. Each report must be submitted 
within 30 days after detection of a large-volume gas release. A large-
volume gas release report is not required if an incident report has 
already been submitted under this part for the same event and the 
release volume identified in the incident report is within 10 percent 
of the total release volume on cessation of the release.
0
4. In Sec.  191.23, revise paragraphs (a)(9) and (b)(2) to read as 
follows:

Sec.  191.23  Reporting safety-related conditions.

    (a) * * *
    (9) Any safety-related condition that could lead to an imminent 
hazard to public safety and causes (either directly or indirectly by 
remedial action of the operator), for purposes other than abandonment, 
a 20% or more reduction in operating pressure or shutdown of operation 
of a pipeline, UNGSF, or an LNG facility that contains or processes gas 
or LNG.
* * * * *
    (b) * * *
    (2) Is an incident or large-volume gas release, or results in an 
incident or large-volume gas release before the deadline for filing the 
safety-related condition report;
* * * * *
0
5. In Sec.  191.29, revise paragraph (a) introductory text, and remove 
paragraph (c) to read as follows:

Sec.  191.29  National Pipeline Mapping System.

    (a) Each operator of a gas transmission pipeline, offshore 
gathering, Type A, Type B, or Type C regulated onshore gathering 
pipeline as determined in Sec.  192.8 of this subchapter, or liquefied 
natural gas facility must provide the following geospatial data to 
PHMSA for that pipeline or facility:
* * * * *

PART 192--TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE: 
MINIMUM FEDERAL SAFETY STANDARDS

0
6. The authority citation for part 192 continues to read as follows:

    Authority: 30 U.S.C. 185(w)(3), 49 U.S.C. 5103, 60101 et seq., 
and 49 CFR 1.97.

0
7. In Sec.  192.3, add the definitions of ``Confined space,'' ``Gas-
associated substructure,'' ``Leak or hazardous leak,'' ``Lower 
explosive limit (LEL),'' ``Substructure,'' ``Tunnel,'' and ``Wall-to-
wall paved area'' in alphabetical order to read as follows:

Sec.  192.3  Definitions.

* * * * *
    Confined space means any subsurface structure, other than a 
building, of sufficient size to accommodate a person, and in which gas 
could accumulate or migrate. These include, vaults, certain tunnels, 
catch basins, and manholes.
* * * * *
    Gas-associated substructure means a substructure that is part of an 
operator's pipeline but that is not itself designed to contain gas.
* * * * *
    Leak or hazardous leak means, for the purposes of all subparts of 
part 192 except Sec.  192.12(d) and subparts O and P, any release of 
gas from a pipeline that is uncontrolled at the time of discovery and 
is an existing, probable, or future hazard to persons, property, or the 
environment, or any uncontrolled release of gas from a pipeline that is 
or can be discovered using equipment, sight, sound, smell, or touch.
* * * * *
    Lower explosive limit (LEL) means the minimum concentration of gas 
or vapor in air below which propagation of a flame does not occur in 
the presence of an ignition source at ambient pressure and temperature.
* * * * *
    Substructure means any subsurface structure that is not large 
enough for a person to enter and in which gas could accumulate or 
migrate. Substructures include, but are not limited to, telephone and 
electrical ducts, and conduit, gas and water valve boxes, and meter 
boxes.
* * * * *
    Tunnel is a subsurface passageway large enough for a person to 
enter and in which gas could accumulate or migrate.
* * * * *
    Wall-to-wall paved area means an area where the ground surface 
between the curb of a paved street and the front wall of a building is 
continuously paved, excluding intermittent landscaping, such as tree 
plots.
* * * * *
0
8. In Sec.  192.9:
0
a. Revise paragraph (b);
0
b. Redesignate paragraphs (d)(4) through (8) as paragraphs (d)(6) 
through (10);
0
c. Add new paragraphs (d)(4) and (5);
0
d. Remove the word ``and'' from the end of paragraph (d)(9);
0
e. Revise newly redesignated paragraph (d)(10), and add paragraphs 
(d)(11) through (13);
0
f. Redesignate paragraphs (e)(1)(iii) through (vii) as paragraphs 
(e)(1)(iv) through (viii);
0
g. Add new paragraph (e)(1)(iii);
0
h. Remove the word ``and'' at the end of paragraph (e)(1)(vii);
0
i. Revise newly redesignated paragraph (e)(1)(viii);
0
j. Add paragraphs (e)(1)(ix) through (xi); and
0
k. Revise paragraph (f).
    The revisions and additions read as follows:

Sec.  192.9  What requirements apply to gathering pipelines?

* * * * *
    (b) Offshore lines. An operator of an offshore gathering line must 
comply with requirements of this part applicable to transmission lines, 
except the requirements in Sec. Sec.  192.13(d), 192.150, 192.285(e), 
192.319(d) through (g), 192.461(f) through (i), 192.465(d) and (f), 
192.473(c), 192.478, 192.485(c), 192.493, 192.506, 192.607, 192.613(c), 
192.619(e), 192.624, 192.710, 192.712, 192.714, 192.763(c)(1)(vi) and 
(c)(3), and in subpart O of this part.
* * * * *
    (d) * * *
    (4) Prepare, update, and follow a manual of written procedures for 
conducting operations, maintenance, and emergency response in 
accordance with Sec.  192.605. Compliance with the requirements 
referenced in Sec.  192.605(b)(1), (b)(2), (b)(12), and (e) is only 
required for pipeline facilities that are made subject to such 
requirements under this section or Sec.  191.23;
    (5) Develop and implement procedures for emergency plans in 
accordance with Sec.  192.615;
* * * * *
    (10) Conduct leakage surveys in accordance with Sec.  192.706 
within an advanced leak detection program in accordance with Sec.  
192.763;
    (11) Investigate, grade, repair, and document leaks and leak 
repairs in accordance with Sec. Sec.  192.703(c) through (d), 192.709, 
and 192.760;

[[Page 31973]]

    (12) Conduct patrols in accordance with Sec.  192.705; and
    (13) Maintain and configure pressure relief devices to ensure 
proper device operation and minimize release of gas in accordance with 
Sec.  192.773.
    (e) * * *
    (1) * * *
    (iii) Prepare, update, and follow a manual of written procedures 
for conducting operations, maintenance, and emergency response in 
accordance with Sec.  192.605. Compliance with the requirements 
referenced in Sec.  192.605(b)(1), (2) and (12), (d), and (e) is only 
required for pipeline facilities that are made subject to such 
requirements under this section or Sec.  191.23;
* * * * *
    (viii) Conduct leakage surveys in accordance with Sec. Sec.  
192.706 within an advanced leak detection program in accordance with 
Sec.  192.763;
    (ix) Grade, investigate, repair, and document leaks and leak 
repairs in accordance with Sec. Sec.  192.703(c) and (d), 192.709, and 
192.760;
    (x) Conduct patrols in accordance with Sec.  192.705; and
    (xi) Maintain and configure pressure relief devices to ensure 
proper device operation and minimize release of gas in accordance with 
Sec.  192.773.
* * * * *
    (f) Exceptions. (1) Compliance with paragraphs (e)(1)(ii), (vi), 
and (vii), and (e)(2)(i) and (ii) of this section is not required for 
pipeline segments that are 16 inches or less in outside diameter if one 
of the following criteria are met:
* * * * *
0
9. In Sec.  192.12, revise paragraph (c) to read as follows:

Sec.  192.12  Underground natural gas storage facilities.

* * * * *
    (c) Procedural manuals. Each operator of an UNGSF must prepare and 
follow for each facility one or more manuals of written procedures for 
conducting operations, maintenance, and emergency preparedness and 
response activities under paragraphs (a) and (b) of this section. Such 
manuals must include procedures for eliminating leaks and minimizing 
releases of gas. Each operator must keep records necessary to 
administer such procedures and review and update these manuals at 
intervals not exceeding 15 months, but at least once each calendar 
year. Each operator must keep the appropriate parts of these manuals 
accessible at locations where UNGSF work is being performed. Each 
operator must have written procedures in place before commencing 
operations or beginning an activity not yet implemented.
* * * * *
0
10. In Sec.  192.18, revise paragraph (c) to read as follows:

Sec.  192.18  How to notify PHMSA.

* * * * *
    (c) Unless otherwise specified, if an operator submits, pursuant to 
Sec.  192.8, 192.9, 192.13, 192.179, 192.319, 192.461, 192.506(b), 
192.607(e)(4), 192.607(e)(5), 192.619, 192.624(c)(2)(iii), 
192.624(c)(6),192.632(b)(3), 192.634, 192.636, 192.703(d)(4), 
192.706(a)(2), 192.710(c)(7), 192.712(d)(3)(iv), 192.712(e)(2)(i)(E), 
192.714, 192.745, 192.760(h), 192.763(c), 192.917, 192.921(a)(7), 
192.927, 192.933, or 192.937(c)(7) a notification for use of a 
different integrity assessment method, analytical method, compliance 
period, sampling approach, pipeline material, or technique (e.g., 
``other technology'' or ``alternative equivalent technology'') than 
otherwise prescribed in those sections, that notification must be 
submitted to PHMSA for review at least 90 days in advance of using the 
other method, approach, compliance timeline, or technique. An operator 
may proceed to use the other method, approach, compliance timeline, or 
technique 91 days after submitting the notification unless it receives 
a letter from PHMSA informing the operator that PHMSA objects to the 
proposal or that PHMSA requires additional time and/or more information 
to conduct its review.
* * * * *
0
11. In Sec.  192.167, revise paragraph (a)(2) to read as follows:

Sec.  192.167  Compressor stations: Emergency shutdown.

    (a) * * *
    (2) It must discharge gas from the blowdown piping at a location 
where the gas will not create a hazard to public safety;
* * * * *
0
12. In Sec.  192.169, revise paragraph (b) as follows:

Sec.  192.169  Compressor stations: Pressure limiting devices.

* * * * *
    (b) Each vent line that exhausts gas from the pressure relief 
valves of a compressor station must extend to a location where the gas 
may be discharged without hazard to public safety.
* * * * *
0
13. In Sec.  192.179, revise paragraph (c) to read as follows:

Sec.  192.179  Transmission line valves.

* * * * *
    (c) Each section of a transmission line, other than offshore 
segments, between main line valves must have a blowdown valve with 
enough capacity to allow the transmission line to be blown down as 
rapidly as practicable. Each blowdown discharge must be located so the 
gas can be blown to the atmosphere without hazard to public safety and, 
if the transmission line is adjacent to an overhead electric line, so 
that the gas is directed away from the electrical conductors.
* * * * *
0
14. In Sec.  192.199, revise the section heading and paragraph (e), and 
add paragraph (i) to read as follows:

Sec.  192.199  Requirements for design and configuration of pressure 
relief and limiting devices.

* * * * *
    (e) Have discharge stacks, vents, or outlet ports designed to 
prevent accumulation of water, ice, or snow, located where gas can be 
discharged into the atmosphere without undue hazard to public safety;
* * * * *
    (i) All new, replaced, relocated, or otherwise changed pressure 
relief and limiting devices must be designed and configured, as 
demonstrated by a documented engineering analysis, to minimize 
unnecessary releases of gas by ensuring each of the following:
    (1) The set and reset actuation pressure of the pressure relief 
device and where pressures are taken must minimize release volumes 
beyond what is necessary to provide adequate overpressure protection;
    (2) The design (including sizing and material) and configuration of 
the pressure relief device and its associated piping must be 
appropriate for its set and reset actuation pressure to minimize 
pressure choking, compatible with the composition of transported gas, 
and suitable for reliable operation in expected operating and 
environmental conditions; and
    (3) Installation of the pressure relief device must include 
upstream and downstream isolation valves to facilitate testing and 
maintenance.
0
15. In Sec.  192.361, revise paragraph (f)(3) to read as follows:

Sec.  192.361  Service lines: Installation.

* * * * *
    (f) * * *
    (3) The space between the conduit and the service line must be 
sealed to prevent gas leakage into the building and, if the conduit is 
sealed at both ends, a vent line from the annular space must extend to 
a point where gas would not be a hazard to public safety, and

[[Page 31974]]

extend above grade, terminating in a rain and insect resistant fitting.
* * * * *
0
16. In Sec.  192.363, revise paragraph (c) to read as follows:

Sec.  192.363  Service lines: Valve requirements.

* * * * *
    (c) Each service-line valve on a high-pressure service line, 
installed above ground or in an area where the blowing of gas would be 
hazardous to public safety, must be designed and constructed to 
minimize the possibility of the removal of the core of the valve with 
other than specialized tools.
0
17. In Sec.  192.503 revise paragraph (a)(2) to read as follows:

Sec.  192.503  General requirements.

    (a) * * *
    (2) Each hazardous leak has been located and eliminated.
* * * * *
0
18. In Sec.  192.507, revise paragraph (a) to read as follows:

Sec.  192.507  Test requirements for pipelines to operate at a hoop 
stress less than 30 percent of SMYS and at or above 100 p.s.i. (689 
kPa) gage.

* * * * *
    (a) The pipeline operator must use a test procedure that will 
ensure discovery of all hazardous leaks in the segment being tested.
* * * * *
0
19. In Sec.  192.509, revise paragraph (a) to read as follows:

Sec.  192.509  Test requirements for pipelines to operate below 100 
p.s.i. (689 kPa) gage.

* * * * *
    (a) The test procedure used must ensure discovery of all hazardous 
leaks in the segment being tested.
* * * * *
0
20. In Sec.  192.513, revise paragraph (b) to read as follows:

Sec.  192.513  Test requirements for plastic pipelines.

* * * * *
    (b) The test procedure must ensure discovery of all hazardous leaks 
in the segment being tested.
* * * * *
0
21. In Sec.  192.553, revise paragraph (a)(2) to read as follows:

Sec.  192.553  General requirements.

* * * * *
    (a) * * *
    (2) Each leak detected must be repaired before a further pressure 
increase is made.
* * * * *
0
22. In Sec.  192.557, revise paragraph (b)(2) to read as follows:

Sec.  192.557  Uprating: Steel pipelines to a pressure that will 
produce a hoop stress less than 30 percent of SMYS: plastic, cast iron, 
and ductile iron pipelines.

* * * * *
    (b) * * *
    (2) Make a leakage survey (if it has been more than 1 year since 
the last survey) and repair any leaks that are found.
* * * * *
0
23. In Sec.  192.605, add paragraph (b)(13) to read as follows:

Sec.  192.605  Procedural manual for operations, maintenance, and 
emergencies.

* * * * *
    (b) * * *
    (13) Eliminating leaks and minimizing releases of gas from 
pipelines, as well as remediating or replacing pipelines known to leak 
based on their material, design, or past operating and maintenance 
history.
* * * * *
0
24. In Sec.  192.617, add paragraph (e) to read as follows:

Sec.  192.617  Investigation of failures and incidents.

* * * * *
    (e) Failure defined. For the purposes of this section, the term 
failure means when any portion of a pipeline becomes inoperable, is 
incapable of safely performing its intended function, or has become 
unreliable or unsafe for continued use.
0
25. In Sec.  192.629, revise paragraphs (a) and (b) to read as follows:

Sec.  192.629  Purging of pipelines.

    (a) When a pipeline is being purged of air by use of gas, the gas 
must be introduced into one end of the pipeline in a moderately rapid 
and continuous flow. If gas cannot be supplied in sufficient quantity 
to prevent the formation of a mixture of gas and air hazardous to 
public safety, a slug of inert gas must be introduced into the pipeline 
before the gas.
    (b) When a pipeline is being purged of gas by use of air, the air 
must be introduced into one end of the line in a moderately rapid and 
continuous flow. If air cannot be supplied in sufficient quantity to 
prevent the formation of a mixture of gas and air hazardous to public 
safety, a slug of inert gas must be released into the line before the 
air.
0
26. In Sec.  192.703, revise paragraph (c), and add paragraph (d) to 
read as follows:

Sec.  192.703  General.

* * * * *
    (c) Leaks must be graded and repaired in accordance with the 
requirements in Sec.  192.760.
    (d) Compliance with Sec. Sec.  192.703(c), 192.705 for patrols, 
192.706 for leakage surveys, 192.760(a) through (h) for leak grading 
and repair, 192.763 for advanced leak detection programs, and 192.769 
for qualification of leakage survey personnel, is not required for a 
compressor station on a gas transmission or gathering pipeline if:
    (1) The facility is subject to methane emission monitoring and 
repair requirements under either:
    (i) 40 CFR part 60, subparts OOOOa or OOOOb; or
    (ii) an EPA-approved State plan or Federal plan which includes 
relevant standards at least as stringent as EPA's finalized emissions 
guidelines in 40 CFR part 60, subpart OOOOc;
    (2) The facility is within the first block valve entering or 
exiting the compressor station covered by the emergency shutdown system 
as required in Sec.  192.167 for station isolation from the pipeline; 
and
    (3) Repair records are maintained for the life of the facility in 
accordance with Sec.  192.760(i).
0
27. In Sec.  192.705, revise paragraph (b) to read as follows:

Sec.  192.705  Transmission lines: Patrolling.

* * * * *
    (b) Operators must conduct patrols at least 12 times each calendar 
year at intervals not exceeding 45 days.
* * * * *
0
28. Revise Sec.  192.706 to read as follows:

Sec.  192.706  Transmission lines: Leakage surveys.

    (a) General. Each operator must perform periodic leakage surveys in 
accordance with this section. Each leakage survey must be conducted 
according to the advanced leak detection program requirements in Sec.  
192.763, except that human or animal senses may be used in lieu of leak 
detection equipment only in the following circumstances:
    (1) An offshore gas transmission pipeline below the waterline or 
offshore gathering pipeline below the waterline; or
    (2) An onshore transmission line outside of an HCA or a gathering 
pipeline, each either in a Class 1 or Class 2 location, with advance 
notification to PHMSA in accordance with Sec.  192.18. The notification 
must include tests or analyses demonstrating that the survey method 
would meet the ALDP performance standard in Sec.  192.763(b) or (c) (as 
applicable).

[[Page 31975]]

    (b) Frequency of surveys. Except as provided in paragraphs (c) and 
(d) of this section, leakage surveys must be performed at the following 
intervals:
    (1) Pipelines outside of HCAs must be surveyed at least once per 
calendar year, but with an interval between surveys not to exceed 15 
months; and
    (2) Pipelines in HCAs must be surveyed as follows:
    (i) In Class 1, Class 2, and Class 3 locations, at least twice each 
calendar year, with intervals not exceeding 7\1/2\ months;
    (ii) In Class 4 locations, at least four times each calendar year, 
with intervals not exceeding 4\1/2\ months.
    (c) Non-odorized pipelines. Leakage surveys for pipelines 
transporting gas in conformity with Sec.  192.625 without an odor or 
odorant, must perform leakage surveys using leak detection equipment at 
the following intervals:
    (1) In Class 3 locations, at least twice each calendar year, at 
intervals not exceeding 7\1/2\ months.
    (2) In Class 4 locations, at least four times each calendar year, 
at intervals not exceeding 4\1/2\ months.
    (d) Valves, flanges and certain other facilities. Leakage surveys 
of all valves, flanges, pipeline tie-ins with valves and flanges, ILI 
launcher and ILI receiver facilities, and pipelines known to leak based 
on material (including, cast iron, unprotected steel, wrought iron, and 
historic plastics with known issues), design, or past operating and 
maintenance history, must be performed at the following intervals:
    (1) In Class 1, Class 2, and Class 3 locations, at least twice each 
calendar year, at intervals not exceeding 7\1/2\ months.
    (2) In Class 4 locations, at least four times each calendar year, 
at intervals not exceeding 4\1/2\ months.
0
29. Revise Sec.  192.723 to read as follows:

Sec.  192.723  Distribution systems: Leakage surveys.

    (a) General. Each operator of a gas distribution pipeline must 
conduct periodic leakage surveys with leak detection equipment in 
accordance with this section. All leakage surveys performed pursuant to 
this section must use leak detection equipment that meets the 
requirements of Sec.  192.763.
    (b) Business districts. Leakage surveys must be conducted at least 
once each calendar year, at intervals not exceeding 15 months, 
consisting of atmospheric tests at each gas, electric, telephone, 
sewer, water, or other system manhole; crack in the pavement and 
sidewalks; and any other location that provides an opportunity for 
finding gas leaks.
    (c) Non-business districts. Leakage surveys must be conducted at 
least once every 3 calendar years, at intervals not exceeding 39 
months, unless a shorter inspection interval is required either by 
paragraph (d) of this section, the operator's operations and 
maintenance procedures, or the operator's integrity management plans 
under part 192, subpart P.
    (d) Frequency of regular leakage surveys. Leakage surveys must be 
conducted at least once every calendar year, at intervals not exceeding 
15 months, for:
    (1) Cathodically unprotected distribution pipelines subject to 
Sec.  192.465(e);
    (2) Pipelines known to leak based on their material (including cast 
iron, unprotected steel, wrought iron, and historic plastics with known 
issues), design, or past operating and maintenance history; and
    (3) Gas distribution pipeline systems protected by a distributed 
anode system, in the area of deficient readings identified during a 
cathodic protection survey pursuant to Sec.  195.463 and appendix D, 
until the cathodic protection deficiency is remediated.
    (e) Investigating known leaks after environmental changes. An 
operator must investigate a known leak, including conducting a leakage 
survey for possible gas migration, as soon as practicable when freezing 
ground, heavy rain, flooding, or other changes to the environment occur 
that could affect the venting of gas or could cause migration of gas to 
the outside wall of a building.
    (f) Extreme Weather Surveys. Leakage surveys must be performed 
after extreme weather events and land movement with the likelihood to 
cause damage to the affected pipeline segment. The survey must be 
initiated within 72 hours after the cessation of the event, defined as 
either the point in time when the affected area can be safely accessed 
by the personnel and equipment required to perform the leakage survey 
or when the facility has been returned to service.
0
30. In Sec.  192.727, revise paragraphs (b) and (c) to read as follows:

Sec.  192.727  Abandonment or deactivation of facilities.

* * * * *
    (b) Each pipeline abandoned in place must be disconnected from all 
sources and supplies of gas; purged of gas; in the case of offshore 
pipelines, filled with water or inert materials; and sealed at the 
ends. However, the pipeline need not be purged when the volume of gas 
is so small that there is no potential hazard to public safety.
    (c) Except for service lines, each inactive pipeline that is not 
being maintained under this part must be disconnected from all sources 
and supplies of gas; purged of gas; in the case of offshore pipelines, 
filled with water or inert materials; and sealed at the ends. However, 
the pipeline need not be purged when the volume of gas is so small that 
there is no potential hazard to public safety.
* * * * *
0
31. In Sec.  192.751, revise paragraph (a) to read as follows:

Sec.  192.751  Prevention of accidental ignition.

* * * * *
    (a) When an amount of gas potentially hazardous to public safety is 
being vented into open air, each potential source of ignition must be 
removed from the area and a fire extinguisher must be present.
* * * * *
0
32. Add Sec.  192.760 to read as follows:

Sec.  192.760  Leak grading and repair.

    (a) General. Each operator must have and follow written procedures 
for grading and repairing leaks that meet or exceed the requirements of 
this section.
    (1) These requirements are applicable to leaks on all portions of a 
gas pipeline including, but not limited to, line pipe, valves, flanges, 
meters, regulators, tie-ins, launchers, and receivers.
    (2) The leak grading and repair procedure must prioritize leaks by 
the hazard to public safety and the environment.
    (3) Each leak must be investigated immediately and continuously 
until a leak grade determination has been made.
    (b) Grade 1 leaks. (1) A grade 1 leak is any leak that constitutes 
an existing or probable hazard to persons or property or a grave hazard 
to the environment. A grade 1 leak includes a leak with any of 
following characteristics:
    (i) Any leak that, in the judgment of operating personnel at the 
scene is regarded as an existing or probable hazard to public safety or 
a grave hazard to the environment;
    (ii) Any amount of escaping gas has ignited;
    (iii) Any indication that gas has migrated into a building, under a 
building, or into a tunnel;
    (iv) Any reading of gas at the outside wall of a building, or areas 
where gas could migrate to an outside wall of a building;
    (v) Any reading of 80% or greater of the LEL (60% for LPG systems) 
in a confined space;

[[Page 31976]]

    (vi) Any reading of 80% or greater of the LEL (60% for LPG systems) 
in a substructure, (including gas associated substructures) from which 
any gas could migrate to the outside wall of a building;
    (vii) Any leak that can be seen, heard, or felt; or
    (viii) Any leak defined as an incident in Sec.  191.3.
    (2) An operator must promptly repair a grade 1 leak and eliminate 
the hazardous conditions by taking immediate and continuous action by 
operator personnel at the scene. Immediate action means the operator 
will begin instant efforts to remediate and repair the leak upon 
detection and to eliminate any hazardous conditions caused by the leak. 
Continuous means that the operator must maintain on-site remediation 
efforts until the leak repair has been completed. This may require one 
or more of, but not limited to, the following actions be taken without 
delay:
    (i) Implementing an emergency plan pursuant to Sec.  192.615;
    (ii) Evacuating premises;
    (iii) Blocking off an area;
    (iv) Rerouting traffic;
    (v) Eliminating sources of ignition;
    (vi) Venting the area by removing manhole covers, bar holing, 
installing vent holes, or other means;
    (vii) Stopping the flow of gas by closing valves or other means; or
    (viii) Notifying emergency responders.
    (c) Grade 2 leaks. (1) A grade 2 leak constitutes a probable future 
hazard to persons or property or a significant hazard to the 
environment, and includes any leak (other than a grade 1 leak) with any 
the following characteristics:
    (i) A reading of 40% or greater of the LEL under a sidewalk in a 
wall-to-wall paved area that does not qualify as a grade 1 leak;
    (ii) A reading at or above 100% of LEL under a street in a wall-to-
wall paved area that has gas migration and does not qualify as a grade 
1 leak;
    (iii) A reading between 20% and 80% of the LEL in a confined space;
    (iv) A reading less than 80% of the LEL in a substructure (other 
than gas associated substructures) from which gas could migrate;
    (v) A reading of 80% or greater of the LEL in a gas associated 
substructure from which gas could not migrate;
    (vi) Any reading of gas that does not qualify as a grade 1 leak 
that occurs on a transmission pipeline or a Type A or Type C regulated 
gas gathering line;
    (vii) Any leak with a leakage rate of 10 cubic feet per hour (CFH) 
or more that does not qualify as a grade 1 leak;
    (viii) Any leak of LPG or hydrogen gas that does not qualify as a 
grade 1 leak; or
    (ix) Any leak that, in the judgment of operating personnel at the 
scene, is of sufficient magnitude to justify scheduled repair within 
six months or less.
    (2) An operator must schedule repair based on the severity or 
likelihood of hazard to persons, property, or the environment. A grade 
2 leak must be repaired within six months of detection, unless a 
shorter repair deadline is required by the operator's procedures, 
integrity management program, or paragraphs (c)(3) through (6) of this 
section. The operator must re-evaluate each grade 2 leak at least once 
every 30 days until it is repaired.
    (3) The operator must complete repair of any grade 2 leak on a gas 
transmission or Type A gathering pipeline, each located in an HCA, 
Class 3 or Class 4 location, within 30 days of detection. If repair 
cannot be completed within 30 days due to permitting requirements or 
parts availability, the operator must take continuous action to monitor 
and repair the leak.
    (4) Each operator's operations and maintenance procedure must 
include a methodology for prioritizing the repair of grade 2 leaks, 
including criteria for leaks that warrant repair within 30 days of 
detection pursuant to Sec.  192.760(c). Grade 2 leaks with a repair 
deadline of less than 30 days must be re-evaluated at least once every 
2 weeks until the repair is complete. This methodology must include an 
analysis of, at a minimum, each of the following parameters:
    (i) The volume and migration of gas emissions;
    (ii) The proximity of gas to buildings and subsurface structures;
    (iii) The extent of pavement; and
    (iv) Soil type and conditions, such as frost cap, moisture, and 
natural venting.
    (5) Each operator must take immediate and continuous action to 
complete repair of a grade 2 leak and eliminate the hazard when 
freezing ground, heavy rain, flooding, new pavement, or other changes 
to the environment are anticipated or occur near an existing grade 2 
leak that may affect the venting or migration of gas and could allow 
gas to migrate to the outside wall of a building.
    (6) An operator must complete repair of known grade 2 leaks 
existing on or before [effective date of the final rule] before [date 1 
year after the publication date of the final rule].
    (d) Grade 3 leaks. (1) A grade 3 leak is any leak that does not 
meet the criteria of a grade 1 or grade 2 leak. In order to qualify as 
a grade 3 leak, none of the criteria for grade 1 or 2 leaks must be 
present. Grade 3 leaks may include, but are not limited to, leaks with 
the following characteristics:
    (i) A reading of less than 80% of the LEL in gas associated 
substructures from which gas is unlikely to migrate; or
    (ii) Any reading of gas under pavement outside of a wall-to-wall 
paved area where gas is unlikely to migrate to the outside wall of a 
building; or
    (iii) A reading of less than 20% of the LEL in a confined space.
    (2) A grade 3 leak must be repaired within 24 months of detection, 
except as described below:
    (i) A grade 3 leak known to exist on or before [effective date of 
the final rule] must be repaired prior to [date 3 years after the 
publication date of the final rule].
    (ii) A grade 3 leak may be evaluated in accordance with paragraph 
(d)(3) of this section and repairs postponed if the segment containing 
the leak is scheduled for replacement, and is replaced, within five 
years of detection of the leak.
    (3) Each operator must re-evaluate each grade 3 leak at least once 
every six months until repair of the leak is complete.
    (e) Post-repair inspection. (1) A leak repair is considered to be 
complete when an operator obtains a gas concentration reading of 0% gas 
at the leak location after a permanent repair.
    (2) An operator must conduct a post-repair leak inspection at least 
14 days after but no later than 30 days after the date of the repair to 
determine if the repair was complete.
    (3) If a post-repair inspection shows a gas concentration reading 
greater than 0% gas, the repair is not complete, and operator must take 
the following actions:
    (i) If the post repair inspection finds gas concentrations or 
migration indicating that the potential for a grade 1 or grade 2 
condition leak exists, the operator must re-inspect the repair and take 
immediate and continuous action to eliminate the hazard and complete 
repair;
    (ii) If the operator's post repair inspection does not find a gas 
concentration reading of 0% at the leak location, and a grade 1 or 
grade 2 condition does not exist, then the operator must remediate the 
repair and re-inspect the leak within 30 days and continue reevaluating 
the leak at least once every 30 days until there is a gas concentration 
reading of 0%. Leak repair must be complete within the repair deadline 
for a grade 3 leak under Sec.  192.760(d)(2), or for a downgraded leak, 
the repair deadline under Sec.  192.760(g).

[[Page 31977]]

    (4) A post repair inspection is not required for any leak that is 
eliminated by routine maintenance work--such as adjustment or 
lubrication of above-ground valves, or tightening of packing nuts on 
valves with seal leaks--and is a grade 3 leak or occurs on an 
aboveground pipeline facility.
    (f) Upgrading leak grades. If at any time an operator receives 
information that a higher-priority grade condition exists in connection 
with a previously-graded leak, the operator must upgrade that leak to 
the higher-priority grade. When an operator upgrades a leak to a 
higher-priority grade, the time period to complete the repair is the 
earlier of either the remaining time based on its original leak grade 
or the time allowed for repair under its new leak grade measured from 
the time the operator received the information that a higher-priority 
grade condition exists.
    (g) Downgrading leak grades. A leak may not be downgraded to a 
lower-priority leak grade unless a temporary repair to the pipeline has 
been made or a permanent repair was attempted but gas was detected 
during the post-repair inspection under paragraph (e) of this section. 
In this case, the time period for repair is the remaining time allowed 
for repair under its new grade measured from the time the leak was 
detected.
    (h) Extension of leak repair. An operator may request an extension 
of the leak repair deadline requirements for an individual grade 3 leak 
with advance notification to and no objection from PHMSA pursuant to 
Sec.  192.18. The operator's notification must show that the delayed 
repair timeline would not result in an increased risk to public safety, 
as well as that either the required repair deadline is impracticable, 
or that remediation within the specified time frame would result in the 
release of more gas to the environment than would occur with continued 
monitoring. The notification must include the following:
    (1) A description of the leaking facility including the location, 
material properties, the type of equipment that is leaking, and the 
operating pressure;
    (2) A description of the leak and the leak environment, including 
gas concentration readings, leak rate if known, class location, nearby 
buildings, weather conditions, soil conditions, and other conditions 
that could affect gas migration, such as pavement;
    (3) A description of the alternative repair schedule and a 
justification for the same; and
    (4) Proposed emissions mitigation methods, monitoring, and repair 
schedule.
    (i) Recordkeeping. (1) Records of the complete history of the 
investigation and grading of each leak must be retained for 5 years 
after the final post-repair inspection is completed under paragraph (e) 
of this section. These records include all records documenting leak 
grading, monitoring, inspections, upgrades, and downgrades.
    (2) Records of the detection, remediation, and repair of the leak 
must be retained for the life of the pipeline. This must include the 
date, location, and description of each leak detected, and repair or 
remediation of the same, made on the pipeline.
0
33. Add Sec.  192.763 to read as follows:

Sec.  192.763  Advanced Leak Detection Program.

    (a) Advanced Leak Detection Program (ALDP) elements. Each operator 
must have and follow a written ALDP that includes the following 
elements:
    (1) Leak detection equipment. (i) The ALDP must include a list of 
leak detection equipment used in operator leakage surveys, pinpointing 
leak locations, and investigating leaks.
    (ii) Leak detection equipment used for leakage surveys, pinpointing 
leak locations, investigating, and inspecting leaks must have a minimum 
sensitivity of 5 parts per million for each gas being surveyed. The 
operator must validate the sensitivity of this equipment before using 
the device in a leakage survey by testing with a known concentration of 
gas.
    (iii) Leak detection equipment must be selected based on a 
documented analysis considering, at a minimum, the state of 
commercially available leak detection technologies and practices, the 
size and configuration of the pipeline system, and system operating 
parameters and environment. At a minimum, operators must analyze the 
effectiveness of the following technologies for their systems:
    (A) The use of handheld leak detection equipment capable of 
detecting and locating all leaks of 5 parts per million or more when 
measured within 5 feet of the pipeline or within a wall-to-wall paved 
area, in conjunction with locating equipment to verify the tools are 
sampling the area within 5 feet of the buried pipeline. The procedure 
must include sampling the atmosphere near cracks, vaults, or any other 
surface feature where gas could migrate;
    (B) Periodic surveys performed with leak detection equipment 
mounted on mobile, aerial, or satellite-based platforms that, in 
conjunction with confirmation by hand-held equipment, is capable of 
detecting and pinpointing all leaks of 5 parts per million or more when 
measured within 5 feet of the pipeline, or within a wall-to-wall paved 
area;
    (C) Periodic surveys performed with optical, infrared, or laser-
based leak detection equipment that can sample or inspect the area 
within 5 feet of the pipeline, or within a wall-to-wall paved area, 
capable of detecting and pinpointing all leaks of 5 parts per million 
or more;
    (D) Continuous monitoring for leaks via stationary sensors, 
pressure monitoring, or other means that provide alarms or alerts and 
that, in conjunction with confirmation by hand-held equipment, is 
capable of detecting and pinpointing all leaks of 5 parts per million 
or more when measured within 5 feet of the pipeline, or within a wall-
to-wall paved area; and
    (E) Systematic use of other commercially available technology 
capable of detecting and pinpointing all leaks producing a reading of 5 
parts per million or more within 5 feet of the pipeline, or within a 
wall-to-wall paved area.
    (2) Leak detection practices. At a minimum, an operator must have 
and follow written procedures for:
    (i) Performing leakage surveys. Operators must have procedures for 
performing leakage surveys required for Sec. Sec.  192.706 and 192.723 
using each selected leak detection technology as described in paragraph 
Sec.  192.763(a)(1). The procedures must define environmental and 
operational conditions for which each leak detection technology is and 
is not permissible. The operator's procedures must follow the leak 
detection equipment manufacturer's instructions for survey methods and 
allowable environmental and operational parameters.
    (ii) Pinpointing and investigating leaks. The location of the 
source of each leak indication on an onshore pipeline or any portion of 
an offshore pipeline above the waterline must be pinpointed and 
investigated with handheld leak detection equipment. Leak indications 
on offshore pipelines below the waterline may be pinpointed with human 
senses.
    (iii) Validating performance. Operators must have procedures 
validating that leak detection equipment meets the requirement of 
paragraph (a)(1)(ii) of this section. The operator must have procedures 
for validating the sensitivity of the equipment before initial use by 
testing with a known concentration of gas and at the required offset 
conditions of 5 feet. Records validating equipment performance must be 
maintained for five years after the

[[Page 31978]]

date the device is no longer used by the operator.
    (iv) Maintaining and calibrating leak detection equipment. At a 
minimum, procedures must follow the equipment manufacturer's 
instructions for calibration and maintenance. Leak detection equipment 
must be recalibrated or replaced following any indication of 
malfunction. Records validating equipment calibration and failures 
indicating recalibration is necessary must be maintained for 5 years 
after the date the individual device is retired by the operator.
    (3) Leakage survey frequency. Leakage survey frequency must be 
sufficient to detect all leaks that have a sufficient release rate to 
produce a reading of 5 parts per million or more of gas when measured 
from a distance of 5 feet or less from the pipeline, or within a wall-
to-wall paved area, but may be no less frequent than required in 
Sec. Sec.  192.706 and 192.723. Less sensitive equipment, challenging 
survey conditions, or facilities known to leak based on their material, 
design, or past operating and maintenance history may require more 
frequent surveys to detect leaks consistent with paragraph (b) of this 
section.
    (4) Periodic evaluation and improvement. The ALDP must include 
procedures and records showing the operator is meeting all of the 
program requirements.
    (i) The operator must evaluate the ALDP at least once each calendar 
year but with a maximum interval not to exceed 15 months.
    (ii) The operator must make changes to any program elements 
necessary to locate and eliminate leaks and minimize releases of gas.
    (iii) When considering changes to program elements, operators must 
analyze, at a minimum, the performance of the leak detection equipment 
used, the adequacy of the leakage survey procedures, advances in leak 
detection technologies and practices, the number of leaks that are 
initially detected by the public, the number of leaks and incidents, 
and estimated emissions from leaks detected pursuant to this section.
    (iv) The operator must document any improvements needed to the 
program.
    (b) Advanced leak detection performance standard. Each operator's 
ALDP described in paragraph (a) of this section must be capable of 
detecting all leaks that have a sufficient release rate to produce a 
reading of 5 parts per million or more of gas when measured from a 
distance of 5 feet or less from the pipeline, or within a wall-to-wall 
paved area.
    (1) The performance of the ALDP must be validated and documented 
with engineering tests and analyses.
    (2) Records validating that the ALDP meets the performance standard 
must be maintained for at least 5 years after the date that ALDP is no 
longer used by the operator.
    (c) Alternative advanced leak detection performance standard. For 
gas pipelines other than natural gas pipelines, and for natural gas 
transmission, offshore gathering, and Types A, B, and C gathering 
pipelines located in Class 1 or Class 2 locations, an operator may use 
an alternative ALDP performance standard (and supporting leak detection 
equipment) with prior notification to, and with no objection from, 
PHMSA in accordance with Sec.  192.18. PHMSA will only approve a 
notification if operator, in the notification, demonstrates that the 
alternative performance standard is consistent with pipeline safety and 
equivalent to the standard in paragraph (b) of this section for 
reducing greenhouse gas emissions and other environmental hazards. The 
notification must include:
    (1) Mileage by system type;
    (2) Known material properties, location, HCAs, operating 
parameters, environmental conditions, leak history, and design 
specifications, including coating, cathodic protection status, and pipe 
welding or joining method;
    (3) The proposed performance standard;
    (4) Any safety conditions, such as increased survey frequency;
    (5) The leak detection equipment, procedures, and leakage survey 
frequencies the operator proposes to employ;
    (6) Data on the sensitivity and the leak detection performance of 
the proposed alternative ALDP standard; and
    (7) The gas transported by the pipeline.
0
34. Add Sec.  192.769 to read as follows:

Sec.  192.769  Qualification of leakage survey, investigation, grading, 
and repair personnel.

    Only individuals qualified under subpart N of this part may conduct 
leakage survey, investigation, grading, and repair. Individuals 
qualified under subpart N must also possess training, experience, and 
knowledge in the field of leakage survey, leak investigation, and leak 
grading, including documented work history or training associated with 
those activities.
0
35. Add Sec.  192.770 to read as follows:

Sec.  192.770  Minimizing emissions from gas transmission pipeline 
blowdowns.

    (a) Except as provided in paragraph (b) of this section, when an 
operator performs any intentional release of gas (including blowdowns 
or venting for scheduled repairs, construction, operations, or 
maintenance) from a gas transmission pipeline, the operator must 
prevent or minimize the release of gas to the environment through one 
or more of the following methods:
    (1) Isolating the smallest section of the pipeline necessary to 
complete the task by use of valves or the installation of control 
fittings;
    (2) Routing gas released from the pipeline from the nearest 
isolation valves or control fittings to a flare or to other equipment 
as fuel gas;
    (3) Reducing pressure by use of in-line compression;
    (4) Reducing pressure by use of mobile compression to a segment or 
storage vessel adjacent to the nearest isolation valves;
    (5) Transferring the gas to a segment of a lower pressure pipeline 
system adjacent to the nearest isolation valves; or
    (6) Employing an alternative method demonstrated to result in a 
release volume reduction of at least 50% compared to venting gas 
directly to the atmosphere without mitigative action.
    (b) An operator is not required to comply with the provisions of 
paragraph (a) of this section during an event that activates its 
emergency plan under Sec.  192.615(a)(3) when such minimization would 
delay emergency response or result in a safety risk during pipeline 
assessments or maintenance. Each emergency release conducted without 
mitigation must be documented, including the justification for release 
without mitigation.
    (c) Operators must document the methodologies used in paragraph (a) 
of this section and describe how the methodologies minimize the release 
of gas to the environment.
0
36. Add Sec.  192.773 to read as follows:

Sec.  192.773  Pressure relief device maintenance and adjustment of 
configuration.

    (a) Each operator must develop, maintain, and follow written 
operations and maintenance procedures to assess the proper function of 
pressure limiting or relief device and to repair or replace each failed 
pressure limiting or relief device. When a pressure limiting or relief 
device fails to operate or allows gas to release to the atmosphere at 
an operating pressure above or below the set actuation pressure range 
defined for the device in the operator's operations

[[Page 31979]]

and maintenance procedure, the operator must:
    (1) Assess the pilot, springs, seats, pressure gauges, and other 
components to ensure proper functioning, sensing, and set/reset 
actuation pressures are within actuation pressure tolerances;
    (2) Assess the inlet and outlet piping for piping that restricts 
the inlet or outlet gas flow, piping that restricts the sensing 
pressure, debris, and other restrictions that could impede the 
operation or restrict the capacity to relieve overpressure conditions;
    (3) Repair or replace the device to eliminate the malfunction as 
follows:
    (i) If a pressure relief device activates above its set pressure 
and above the pressure limits in Sec.  192.201(a) or 192.739 as 
applicable, fails to operate, or otherwise fails to provide 
overpressure protection, the operator must repair or replace the device 
or pressure sensing equipment immediately.
    (ii) If a pressure relief device allows gas to release to the 
atmosphere at an operating pressure below the set actuation pressure 
range, the operator must take immediate and continuous action with on-
site personnel to stop the release until the device is repaired or 
replaced. The relief device or pressure sensing equipment must be 
repaired or replaced as soon as practicable but within 30 days.
    (b) Each operator must develop, maintain, and follow written 
operations and maintenance procedures to ensure that a pressure relief 
device configuration, as demonstrated by a documented engineering 
analysis, employs set and reset actuation pressures ensuring 
minimization of release volumes while providing adequate overpressure 
protection.
    (c) Records under this section must be maintained as follows:
    (1) Records of relief devices malfunctions must be maintained for 5 
years after repair or replacement.
    (2) Records pertaining to repair, replacement, or reconfiguration 
(including any engineering analyses) of a pressure relief device must 
be maintained for the life of the pipeline.
0
37. In Sec.  192.1007, revise paragraphs (e)(1)(i) and (v) as follows:

Sec.  192.1007  What are the required elements of an integrity 
management plan?

* * * * *
    (e) * * *
    (1) * * *
    (i) Number of hazardous leaks either eliminated or repaired (or 
total number of leaks if all leaks are repaired when found), 
categorized by cause;
* * * * *
    (v) Number of hazardous leaks either eliminated or repaired (or 
total number of leaks if all leaks are repaired when found), 
categorized by material; and
* * * * *

PART 193--LIQUEFIED NATURAL GAS FACILITIES: FEDERAL SAFETY 
STANDARDS

0
38. The authority citation for part 193 continues to read as follows:

    Authority:  49 U.S.C. 5103, 60102, 60103, 60104, 60108, 60109, 
60110, 60113, 60118; and 49 CFR 1.53.

0
39. In Sec.  193.2503, add paragraph (h) to read as follows:

Sec.  193.2503  Operating procedures.

* * * * *
    (h) Eliminating leaks and minimizing releases of gas.
0
40. Add Sec.  193.2523 to read as follows:

Sec.  193.2523  Minimizing emissions from blowdowns and boiloff.

    (a) Except as provided in paragraph (b) of this section, an 
operator of an LNG facility must minimize intentional emissions of 
natural gas from LNG facilities, including tank boiloff or blowdowns 
for repairs, construction, operations, or maintenance. The operator 
must minimize the release of natural gas to the environment by use of 
one or more of the following methods:
    (1) Isolating a smaller section of the piping segments by use of 
valves or the installation of control fittings;
    (2) Routing gas released from the facility to a flare, or to other 
equipment for use as fuel gas;
    (3) Transferring gas or LNG to a storage tank or local pressure 
vessel; or
    (4) Employing an alternative method demonstrated to result in 
release volume reductions of at least 50% compared to venting gas 
directly to the atmosphere without mitigative action.
    (b) An operator is not required to comply with the provisions of 
paragraph (a) of this section during an emergency resulting in the 
activation of their emergency procedures under Sec.  193.2509. An 
operator must document each emergency release without mitigation 
described in paragraph (b) of this section, including the justification 
for release without mitigation.
    (c) The operator must document the method or methods used and 
describe how those methods minimize the release of natural gas to the 
environment.
0
41. In Sec.  193.2605, add paragraph (b)(3) to read as follows:

Sec.  193.2605  Maintenance procedures.

* * * * *
    (b) * * *
    (3) Procedures for eliminating leaks and minimizing releases of 
gas.
* * * * *
0
42. Add Sec.  193.2624 to read as follows:

Sec.  193.2624  Leakage surveys.

    (a) Each operator of an LNG facility, including mobile, temporary, 
and satellite facilities must conduct periodic methane leakage surveys, 
on equipment and components within their facilities containing methane 
or LNG, at least four times each calendar year, with a maximum interval 
between surveys not exceeding 4\1/2\ months, using leak detection 
equipment. Leak detection equipment must be capable of detecting and 
locating all methane leaks producing a reading of 5 parts per million 
or more of within 5 feet of the component or equipment surveyed.
    (b) Operators must have written procedures providing for each of 
the following:
    (1) Validating the leakage survey equipment and performing leakage 
surveys consistent with the equipment manufacturer's instructions for 
survey methods and allowable environmental and operational parameters;
    (2) Validating the sensitivity of this equipment by the operator 
before initial use by testing with a known concentration of gas at a 
required offset condition of 5 feet; and
    (3) Calibrating the equipment consistent with the equipment 
manufacturer's instructions for calibration and maintenance. Leak 
detection equipment must be recalibrated or replaced following any 
indication of malfunction.
    (c) Each operator must maintain records of the leak survey and 
equipment sensitivity validation and calibration for five years after 
the leakage survey.
    (d) Operators must review the results of the methane leakage 
surveys and address any methane leaks and abnormal operating conditions 
in accordance with their written maintenance procedures or abnormal 
operating procedures.

    Issued in Washington, DC, on May 4, 2023, under authority 
delegated in 49 CFR 1.97.
Alan K. Mayberry,
Associate Administrator for Pipeline Safety.
[FR Doc. 2023-09918 Filed 5-17-23; 8:45 am]
BILLING CODE 4910-60-P