[Federal Register Volume 82, Number 50 (Thursday, March 16, 2017)]
[Notices]
[Pages 14106-14108]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2017-05262]
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DEPARTMENT OF TRANSPORTATION
Pipeline and Hazardous Materials Safety Administration
[Docket No. PHMSA-2016-0131]
Pipeline Safety: Deactivation of Threats
AGENCY: Pipeline and Hazardous Materials Safety Administration (PHMSA),
DOT.
ACTION: Notice; issuance of advisory bulletin.
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SUMMARY: PHMSA is issuing this Advisory Bulletin to inform owners and
operators of gas transmission pipelines that PHMSA has developed
guidance on threat identification and the minimum criteria for
deactivation of threats, as established by a previously issued rule.
This Advisory Bulletin also provides guidance to gas transmission
pipeline operators regarding documenting their rationale of analyses,
justifications, determinations, and decisions related to threat
deactivation.
FOR FURTHER INFORMATION CONTACT: Allan Beshore by phone at (816) 329-
3811 or email at [email protected]. All materials in this docket
may be accessed electronically at http://www.regulations.gov.
Information about PHMSA may be found at http://www.phmsa.dot.gov.
SUPPLEMENTARY INFORMATION:
I. Background
A critical element in an integrity management (IM) program is the
identification of threats to pipeline integrity. As required by section
192.911(c), an IM program must contain ``[a]n identification of threats
to each covered pipeline segment, which must include data integration
and a risk assessment. An operator must use the threat identification
and risk assessment to prioritize covered segments for assessment
(section 192.917) and to evaluate the merits of additional preventive
measures and mitigative measures (section 192.935) for each covered
segment.'' Further requirements detailed in section 192.921(a) state,
``[a]n operator must select the [assessment] method or methods best
suited to address the threats identified to the covered segment.'' The
threats to a particular pipeline segment dictate the type of
assessments the operator must perform to fulfill the requirements of
section 192.921(a).
According to the Standard established by the American Society of
Mechanical Engineers (ASME), ASME B31.8S-2004, Section 2.2, an operator
must consider nine individual threat categories as part of an IM
program. As stated by ASME B31.8S-2004, Section 5.10, an IM program
should provide criteria for eliminating a threat from consideration
during a risk assessment; however, 49 CFR part 192--Subpart O does not
include provisions for the permanent elimination of threats. An
operator, therefore, must continually consider all threats in the
evaluation of their IM program through periodic reviews and
assessments, as required by section 192.937.
PHMSA acknowledges that threats may be categorized as active,
requiring an integrity assessment, or inactive, meaning that during a
specific assessment cycle the threat does not trigger an integrity
assessment, per section 192.921(a). Operators, however, must understand
that threats to a pipeline are not static, but vary over time. Changes
in threats can occur suddenly, as in the case of catastrophic outside
forces like hurricanes, earthquakes, or down-slope land movements, or
they can be gradual changes, such as the introduction of new wet-
production gas sources into a previously dry gas environment. Issues
may also develop into active threats over time, such as coating
degradation that allows stress corrosion cracking or external corrosion
to develop. In other cases, threats may become inactive over time due
to pipeline replacement programs, the implementation of effective
preventative actions, or other improvements to systems.
The periodic review required by section 192.937 for a mature IM
plan must include the re-analysis of the nine threat categories to
determine status changes for active or inactive threats. An operator
must continually monitor operations and maintenance (O&M) and other
activities, integrating relevant information during a threat analysis
that might indicate a change in the status of a threat. Some operators
inappropriately label threats as inactive after they are eliminated
from consideration during prior reviews and assessments, ignoring the
continuous supply of new information provided during routine O&M
activities.
Some operators have opted to eliminate threats from consideration
based on a lack of data, including missing, incomplete, or
unsubstantiated data. Using insufficient data to eliminate a threat is
not technically justified and is contrary to the guidance in ASME
B31.8S-2004, Appendices A1-A9. Each of these appendices includes
language that states, ``[w]here the operator is missing data,
conservative assumptions shall be used when performing the risk
assessment or, alternatively, the segment shall be prioritized
higher.'' Additionally, section 192.947(d) requires that operators
maintain, ``[d]ocuments to support any decision, analysis and process
developed and used to implement and evaluate each element of the
baseline assessment plan and integrity management program.'' Section
192.947(d) further states, ``[d]ocuments include those developed and
used in support of any identification, calculation, amendment,
modification, justification, deviation and determination made, and any
action taken to implement and evaluate any of the program elements.''
PHMSA provides the following guidance for determining the active or
inactive status of the nine threat categories, with the understanding
that the status of a threat will change over time:
Time-Dependent Threats
1. External Corrosion
For steel pipelines, the threat of external corrosion may never be
eliminated.
2. Internal Corrosion
An operator should consider the past operational history of the
pipeline, including, but not limited to: Upset conditions, gas
monitoring (including partial-pressure analysis), bacterial culture
tests, flow direction and rates, gas sources, solid and liquid
analyses, critical angles and liquid holdup points, pigging and other
cleaning history, the presence of internal coatings, chemical
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treatments, and internal pipeline inspection reports.
After consideration of operational history and supporting
documentation, the threat of internal corrosion may be deemed inactive
if:
i. It can be demonstrated that a corrosive gas is not being
transported, per section 192.475(a);
ii. In-line inspection data confirms that a corrosive environment
does not exist within the pipeline; or
iii. Application of internal corrosion direct assessment (ICDA)
demonstrates that there is no internal corrosion occurring at the most
likely locations, and is accompanied by sufficient documentation to
demonstrate the assumptions used with the ICDA model (normally dry gas
with occasional upsets) are valid for the pipeline's entire operating
history.
The threat of internal corrosion should be considered active if:
i. Production, storage, or non-pipeline-quality gas was transported
at any time during the history of the pipeline;
ii. The pipeline has been converted from another type of service
that is susceptible to internal corrosion;
iii. Unmonitored or inoperative drips, siphons, dead legs, or other
liquid holdup points are present anywhere in the pipeline;
iv. There is evidence that liquids from drips, siphons, dead legs,
or other liquid holdup points are present anywhere in the pipeline;
v. Pipe inspection reports, as required by section 192.475(b),
indicate evidence of internal corrosion; or
vi. The operator does not have a complete pipeline operating
history.
3. Stress Corrosion Cracking
The threat of stress corrosion cracking (SCC) should always be
considered active. The operator must continually inspect the pipeline
for the presence of SCC during pipeline examination, as required by
section 192.459.
Static or Stable Threats
4. Manufacturing
There is substantial guidance provided in the original Gas
Transmission IM protocols (e.g. Protocol C.01 Threat Identification),
part 192--subpart O, ASME B31.8S-2004, and the PHMSA Gas Transmission
IM FAQs (e.g., 219, 220, 221, and 231) regarding the deactivation of
manufacturing threats for a segment for any given assessment cycle.
Some of this guidance includes FAQ 219 (manufacturing and construction
(M&C) defects when subpart J tested), FAQ 220 (M&C defects when never
subpart J tested), and FAQ 231 (5-year operating history).
Additionally, section 192.917(e)(3) provides guidance for
determining when a manufacturing threat is active. Section
192.917(e)(3) states, ``[i]f any of the following changes occur in the
covered segment, an operator must prioritize the covered segment as a
high-risk segment for the baseline assessment or a subsequent
reassessment.
i. Operating pressure increases above the maximum operating
pressure experienced during the preceding five years;
ii. MAOP increases; or
iii. The stresses leading to cyclic fatigue increase.''
5. Construction
There is substantial guidance provided in the original Gas
Transmission IM protocols, part 192--subpart O, ASME B31.8S-2004, and
the PHMSA Gas Transmission IM FAQs regarding deactivation of
construction threats for a segment for any given assessment cycle. Some
of this guidance includes FAQ 219 (M&C defects when subpart J tested),
FAQ 220 (M&C defects when never subpart J tested), and FAQ 231 (5-year
operating history).
Section 192.917(e)(3) provides guidance for determining when a
construction threat is active, stating, ``[i]f any of the following
changes occur in the covered segment, an operator must prioritize the
covered segment as a high-risk segment for the baseline assessment or a
subsequent reassessment:
i. Operating pressure increases above the maximum operating
pressure experienced during the preceding five years;
ii. MAOP increases; or
iii. The stresses leading to cyclic fatigue increase.''
6. Equipment
An equipment threat is defined in ASME B31.8S-2004, Appendix A6.1,
as pressure control equipment, relief equipment, gaskets, O-rings,
seal/pump packing, or any equipment other than pipe and pipe
components. The equipment threat may be inactive depending on an
operator's history and review of the records, as required by sections
192.613, 192.617, 192.603, 192.605, 192.739, and 192.743. Operating
history, failures, and abnormal operations records should be evaluated
by integrity personnel to assist in determining trends and issues that
may not be recognized by local or other operations personnel.
As identified in ASME B31.8S-2004, Appendix A6.4, assessments for
equipment threats are normally conducted during maintenance activities,
per the requirements of the O&M procedures. Monitoring the data from
operating history and failures is essential for identifying trends
related to this threat. Communication between O&M and integrity
personnel is a key component to integrating this threat, as well as the
potential increased risk that it poses to pipeline segments, into risk
assessments.
Preventative measures and mitigative measures are an important
factor in maintaining the inactive status of equipment threats. For
example, recognizing a system-wide problem with set point drift in a
particular regulator may necessitate a shorter maintenance cycle or the
replacement of the in-service regulators impacted by this problem.
Time Independent Threats
7. Third-Party Damage
The third-party threat should never be considered inactive.
8. Incorrect Operations
Incorrect operations are defined in ASME B31.8S-2004, Appendix
A8.1, as incorrect operating procedures or failure to follow a
procedure. This threat should always be considered active.
9. Weather-Related and Outside Forces
Weather-related and outside forces are defined in ASME B31.8S-2004,
Appendix A9.1, as earth movement, heavy rains or floods, cold weather
and lightning, or events that may cause pipe to be susceptible to
extreme loading. This threat should always be considered active.
Cyclic Fatigue
In addition to the nine threats referenced in ASME B31.8S-2004,
Sec. 192.917(e)(2) states, ``[a]n operator must evaluate whether
cyclic fatigue or other loading condition (including ground movement,
suspension bridge condition) could lead to a failure or a deformation,
including a dent or gouge, or other defect in the covered segment. An
evaluation must assume the presence of threats in the covered segment
that could be exacerbated by cyclic fatigue. An operator must use the
results from the evaluation together with the criteria used to evaluate
the significance of this threat to the covered segment to prioritize
the integrity baseline assessment or reassessment.''
Cyclic fatigue is a concern because it is a threat that interacts
with all other threats. Interactive threats are two or more threats
acting on a pipeline or pipeline segment that increase the
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probability of failure to a level significantly greater than the
effects of the individual threats acting alone. In order to manage
cyclic fatigue, therefore, operators must have system-specific data
applicable to their unique operating environment to justify the
inactive status of the cyclic fatigue threat. A system-wide or generic
study of cyclic fatigue may be used by an operator as long as the
operator documents why the study is applicable to the segment-specific
conditions.
II. Advisory Bulletin (ADB-2017-01)
To: Owners and Operators of Natural Gas Transmission Pipelines
Subject: Deactivation of Threats
Advisory: The threats identified in ASME B31.8S-2004 may be
considered active or inactive, but are never permanently eliminated.
ASME B31.8S-2004, Appendix A, identifies the information an operator
must collect and analyze for threats, which must demonstrate an
individual threat is not acting on the pipe before an operator can
properly declare the threat inactive for each assessment period. A
threat must be considered active if any data required by Appendix A is
missing, as lack of data indicating the existence of a threat is not
acceptable justification for considering the threat inactive. Documents
to support the determination of an inactive threat status must be
maintained, as per the requirements of Sec. 192.947(d). An operator
does not need to assess a threat for the current assessment cycle if
that threat is properly deemed inactive. When conditions warrant a
review or new information becomes available during the required Sec.
192.937 evaluation operators are required to examine each applicable
threat to determine its active or inactive status.
Issued in Washington, DC, on March 9, 2017, under authority
delegated in 49 CFR 1.97.
Alan K. Mayberry,
Associate Administrator for Pipeline Safety.
[FR Doc. 2017-05262 Filed 3-15-17; 8:45 am]
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