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Safety Recommendation Details

Safety Recommendation P-15-021
Details
Synopsis: There are approximately 298,000 miles of onshore natural gas transmission pipelines in the United States. Since 2004, the operators of these pipelines have been required by the Pipeline and Hazardous Materials Safety Administration (PHMSA) to develop and implement integrity management (IM) programs to ensure the integrity of their pipelines in populated areas (defined as high consequence areas [HCAs]) to reduce the risk of injuries and property damage from pipeline failures. An operator’s IM program is a management system designed and implemented by pipeline operators to ensure their pipeline system is safe and reliable. An IM program consists of multiple components, including procedures and processes for identifying HCAs, determining likely threats to the pipeline within the HCA, evaluating the physical integrity of the pipe within the HCA, and repairing or remediating any pipeline defects found. These procedures and processes are complex and interconnected. Effective implementation of an IM program relies on continual evaluation and data integration. The IM program is an ongoing program that is periodically inspected by PHMSA and/or state regulatory agencies to ensure compliance with regulatory requirements.
Recommendation: TO THE PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION: Develop and implement a plan for eliminating the use of direct assessment as the sole integrity assessment method for gas transmission pipelines.
Original recommendation transmittal letter: PDF
Overall Status: Open - Acceptable Response
Mode: Pipeline
Location: United States
Is Reiterated: No
Is Hazmat: No
Is NPRM: No
Accident #: DCA14SS002
Accident Reports:
Report #: SS-15-01
Accident Date: 11/20/2013
Issue Date: 2/10/2015
Date Closed:
Addressee(s) and Addressee Status: PHMSA (Open - Acceptable Response)
Keyword(s):

Safety Recommendation History
From: NTSB
To: PHMSA
Date: 2/21/2018
Response: We note your position that your NPRM, “Pipeline Safety: Safety of Gas Transmission and Gathering Pipelines,” will allow direct assessment only in instances when the line cannot be inspected with internal tools or when it is not practical to assess it using pressure testing or other specified methods (due to low operating pressures and flows, lack of inspection technology, or presence in a critical delivery area, such as a hospital or nursing home), and you believe that this will meet the intent of the recommendation. In our June 6, 2016, comments about this NPRM, we urged you to require pipeline operators to augment the direct assessment method wherever it is used with appropriate additional integrity assessment methods, such as magnetic flux leakage, ultrasonic testing, and tests directed at determining the integrity of the pipe coating. In our December 5, 2016, letter about this recommendation, we said that a final rule based on the NPRM would not satisfy this recommendation. We issued Safety Recommendation P-15-21 in our special study, Integrity Management of Gas Transmission Pipelines in High Consequence Areas, because we concluded that there are many limitations to direct assessment, including that it: • Is limited to detecting defects attributed to corrosion threats. • Only covers very short subsegments of the pipeline. • Relies on the operator’s selection of specific locations for excavation and direct examination. • Yields far fewer identifications of anomalies compared to ILI. In comparison, ILI and pressure testing assess the entire pipeline segment (not just a subsegment) and can detect defects associated with multiple threats. These tools provide an added safeguard if a threat is misidentified or if other deficiencies exist in the risk analysis processes. We further concluded that the pipeline operator’s selections for direct assessment must be subject to strict scrutiny because of the numerous limitations of such a narrow perspective. We note that operators must choose assessment methods based on the specific threats to pipeline segments revealed by their risk assessments; therefore, they would only use direct assessment as the sole assessment method in response to specific corrosion and stress corrosion cracking threats. If an operator’s risk assessment identifies other threats to a pipeline, the operator must supplement direct assessment with additional assessment methods. In our study, we identified five HCA incidents between 2010 and 2013 that were caused by failures that should have been discovered by one of the four integrity assessment methods. Four of the five incidents involved HCA pipeline segments that were assessed for integrity by direct assessment, with only one actually excavated for examination. Because direct assessment methods were used in these four HCA pipeline segments, corrosion was identified as the threat to which these segments were most susceptible. However, three out of these four incidents were attributed to causes other than corrosion, demonstrating that the integrity assessment methods chosen for these pipeline segments were inadequate. We note that, to address this issue, on March 16, 2017, you issued AB 2017-01, which helps gas transmission pipeline operators identify threats and establishes minimum criteria to deactivate threats using appropriate integrity assessment methods. Our NPRM comments noted that you should require additional IM tests in conjunction with direct assessment, such as magnetic flux leakage, ultrasonic testing, and tests directed at determining the integrity of the pipe coating. You replied, however, that pipe coating inspections occur as a part of a direct assessment, and that the other suggested tests are conducted via ILI and require operators to have piggable pipelines. You pointed out that the NPRM proposed allowing direct assessment only when the line cannot be inspected by ILI tools, or when it is impractical to assess using pressure testing or other specified methods (due to low operating pressures and flows, lack of inspection technology, or presence in critical delivery areas, such as hospitals and nursing homes). Further, the NPRM proposes requiring that all new and replaced lines be piggable, so the number of unpiggable lines will be continually decreasing. You believe that these actions taken together represent a plan to eliminate the use of direct assessment as the sole integrity assessment method for gas transmission pipelines. We have reconsidered our previous position that these actions would not satisfy Safety Recommendation P 15-21. We note that you expected to publish the final rule based on the NPRM by the end of 2017, but publication has been delayed because of the executive order imposing a governmentwide moratorium on new regulations and requiring a review of all pending regulations. Pending issuance of a final rule requiring that all new and replacement gas lines be piggable, Safety Recommendation P-15-21 is classified OPEN--ACCEPTABLE RESPONSE.

From: PHMSA
To: NTSB
Date: 11/13/2017
Response: -From Howard R. Elliott, Administrator: PHMSA notes that we have responded that we only concur in part to this recommendation. PHMSA's current and anticipated rulemakings provide operators with standards and guidelines for conducting direct assessment as a part of a holistic integrity management (IM) plan. Therefore, PHMSA requests the NTSB consider this recommendation "Open-Acceptable Alternative Response." Direct assessment occurs as an integral part of a full IM program. Operators must choose assessment methods based on the specific threats to specific pipeline segments per an operator's risk assessment. Therefore, an operator should only perform direct assessment as a sole assessment method in response to specific corrosion and SCC threats and would not perform extraneous assessments for nonexistent threats. However, if, through a risk assessment, operators identify other threats to a pipeline, operators must supplement direct assessment with additional assessment methods to address those threats. On March 16, 2017, PHMSA issued Advisory Bulletin 2017-01, Deactivation of Threats (82 FR 14106, https ://www.federalregister.gov I documents/2017/03/16/2017-05262/pipelinesafety-deactivation-of-threats ), to support selection of appropriate integrity assessment method(s) to address threats to the integrity of a pipeline by detailing regulatory expectations for minimum criteria for deactivation of threats by operators when considering integrity assessment methods to use. ADB-2017-01 discusses threat identification and the minimum criteria for deactivation of threats, as established by previously issued IM rules and also provides guidance to gas transmission pipeline operators regarding documenting their rationale of analyses, justifications, determinations, and decisions related to threat deactivation. In their comments to the NPRM, the NTSB urged PHMSA to require operators to augment direct assessment with appropriate additional integrity assessment methods. However, PHMSA's current regulations already require direct assessment to be performed as part of an IM process, which includes (1) pre-assessment, including a feasibility study to determine if direct assessment is appropriate; (2) indirect examinations and inspections; (3) direct examinations and evaluations via excavation, including metal-loss measurements, estimated corrosion growth rates, coating examination, and other tests; and (4) post-assessment, including validation digs to confirm the effectiveness of the direct assessment process. We note that the NTSB requested PHMSA require additional IM tests in conjunction with DA, such as magnetic flux leakage, ultrasonic testing, and tests directed at determining the integrity of the pipe coating. Pipe coating inspections occur as a part of a direct assessment, and the other suggested tests are conducted via ILI and require operators to have piggable pipelines. PHMSA's NPRM titled "Pipeline Safety: Safety of Gas Transmission Pipelines" (81 FR 20721 ), published on April 8, 2016 (https://www.federalregister.gov I documents/2016/04/08/2016-063 82/pipeline-safetysafety-of-gas-transmission-and-gathering-pipelines ), proposed to allow the use of direct assessment only in instances where the line is not capable of inspection by internal inspection tools or where it is not practical to assess using pressure testing or other methods specified (due to low operating pressures and flows, lack of inspection technology, and critical delivery areas such as hospitals and nursing homes). Additionally, new and replaced lines are required to be piggable, so the amount of unpiggable lines is continually decreasing. Operators also prefer to run ILI when possible, as it is more cost effective for them. The NPRM also proposed to update these standards incorporated by reference to include NACE SP0206-2006, "Internal Corrosion Direct Assessment Methodology for Pipelines Carrying Normally Dry Natural Gas," for addressing ICDA, and NACE SP0204-2008, "Stress Corrosion Cracking Direct Assessment," for addressing SCCDA. PHMSA has reviewed the NACE standard and finds that it is more comprehensive and rigorous than either§ 192.927 or ASME B31.8S in many respects. PHMSA believes that the direct assessment standards updates and the current IM expectations regarding the direct assessment process along with PHMSA issuance of ADB-2017-01 requirements to establish minimum criteria for deactivation of threats will meet the intent of the recommendation, while continuing to satisfy PHMSA's obligation under§ 60102(m) to have standards for the use of direct assessment. PHMSA held Gas Pipeline Advisory Committee (GPAC) meetings on the rule on January 12, 2017, and on June 6-7, 2017. PHMSA plans to hold additional meetings in December 2017 to continue discussing the proposed rule. The final rule was initially expected to publish by the end of2017. Due to the continued process of gathering GP AC recommendations, we are expecting delays and currently assessing impacts. Like many other issues before us, this is part of an ongoing regulatory review pursuant to the executive order issued by the President.

From: NTSB
To: PHMSA
Date: 12/5/2016
Response: We note your position that your NPRM, “Pipeline Safety: Safety of Gas Transmission and Gathering Pipelines,” published on April 8, 2016, will allow direct assessment only in instances where the line cannot be inspected with internal tools or where it is not practical to assess it using pressure testing or other methods specified (due to low operating pressures and flows, lack of inspection technology, or presence in a critical delivery area, such as a hospital or nursing home), and it is your belief that this will meet the intent of the recommendation. We disagree that these actions will satisfy the recommendation. In our June 6, 2016, comments to this NPRM, we urged you to require pipeline operators to augment the direct assessment method wherever it is used with appropriate additional integrity assessment methods, such as magnetic flux leakage, ultrasonic testing, and tests directed at determining the integrity of the pipe coating. Pending publication and our review of a final rule that addresses these concerns, Safety Recommendation P-15-21 is classified OPEN—UNACCEPTABLE RESPONSE.

From: PHMSA
To: NTSB
Date: 8/17/2016
Response: -From Marie Therese Dominguez, Administrator: At this time, PHMSA is not able to eliminate the use of direct assessment as the sole integrity assessment method for gas transmission pipelines. Title 49, United States Code Section 60102(m), Inspections By Direct Assessment, states that the Secretary shall issue regulations prescribing standards for inspection of a pipeline facility by direct assessment. The Gas Transmission NPRM published on April 8, 20 l 6, would allow the use of direct assessment only in instances where the line is not capable of inspection by internal inspection tools or where it is not practical to assess using pressure testing or other methods specified (due to low operating pressures and flows, lack of inspection technology, and critical delivery areas such as hospitals and nursing homes). PHMSA believes that this will meet the intent of the recommendation.

From: NTSB
To: PHMSA
Date: 6/6/2016
Response: The National Transportation Safety Board (NTSB) has reviewed the Pipeline and Hazardous Materials Safety Administration (PHMSA) notice of proposed rulemaking (NPRM), Pipeline Safety: Safety of Gas Transmission and Gathering Pipelines, published on April 8, 2016. This NPRM addresses issues raised in an August 25, 2011, advance notice of proposed rulemaking (ANPRM) regarding the revision of pipeline safety regulations applicable to the safety of gas transmission and gas gathering pipelines, particularly those involving integrity management (IM). PHMSA also intends to revise the pipeline inspection requirements to allow the direct assessment method to be used “only if a line is not capable of inspection by internal inspection tools.” However, this directly conflicts with the recommendations of our pipeline safety study, Integrity Management of Gas Transmission Lines in High Consequence Areas, which recommended that PHMSA: Develop and implement a plan for eliminating the use of direct assessment as the sole integrity assessment method for gas transmission pipelines. (P-15-21) Our study addressed the many limitations of direct assessment and stated that relying only on direct assessment as a primary avenue for IM is ineffective—direct assessment is used to evaluate pipeline corrosion threats only. Unlike ILI and pressure tests, direct assessment evaluates only the condition of selected pipe areas where the operator suspects a problem. Further, it provides information only about threats that the operator is specifically looking for at locations where the threats are suspected. Among the conclusions of the study was the following: There are many limitations to direct assessment, including that (1) it is limited to the detection of defects attributed to corrosion threats, (2) it only covers very short sub-segments of the pipeline, (3) it relies on the operator’s selection of specific locations for excavation and direct examination, and (4) it yields far fewer identifications of anomalies compared to in-line inspection. We urge PHMSA to require pipeline operators to augment the direct assessment method wherever it is used with appropriate additional integrity assessment methods such as magnetic flux leakage, ultrasonic testing, and tests directed at determining the integrity of the pipe coating.

From: NTSB
To: PHMSA
Date: 1/4/2016
Response: CC# 201501073: The National Transportation Safety Board (NTSB) has reviewed the Pipeline and Hazardous Materials Safety Administration (PHMSA) notice of proposed rulemaking (NPRM), Pipeline Safety: Safety of Hazardous Liquid Pipelines, published on October 13, 2015. In this notice, PHMSA is proposing amendments to the pipeline safety regulations that address requirements of the Pipeline Safety, Regulatory Certainty, and Job Creation Act of 2011, and update and clarify certain regulatory requirements. The study also concluded that there are many limitations to direct assessment, including that: (1) it is limited to the detection of defects attributed to corrosion threats, (2) it only covers very short subsegments of the pipeline, (3) it relies on the operator’s selection of specific locations for excavation and direct examination, and (4) it yields far fewer identifications of anomalies compared to ILI. In comparison, ILI and pressure testing assess the entire pipeline segment (not just a subsegment) and are capable of detecting defects associated with multiple threats. The following recommendation was issued to PHMSA to correct this shortcoming: Develop and implement a plan for eliminating the use of direct assessment as the sole integrity assessment method for gas transmission pipelines. (P-15-21) In its May 12, 2015, response letter, PHMSA agreed with the finding and is moving forward with allowing direct assessment inspection on gas transmission pipelines “only in instances where the line is not capable of inspection by internal inspection tools or where it is not practical to assess using pressure testing or other methods specified.” Therefore, the NTSB asks that PHMSA harmonize the gas and liquid regulations to the maximum extent practicable. Furthermore, PHMSA should include a strong cautionary statement to stress that direct assessment is an ineffective alternative technology for IM when applying the 10-year assessment requirement for the integrity of an entire pipeline. The owner/operator IM program should encompass a broad range of available IM technologies including, but not limited to, ILI, magnetic flux leakage, ultrasonic testing, and tests directed at determining the integrity of the pipe coating.

From: NTSB
To: PHMSA
Date: 7/15/2015
Response: We note your position that you cannot eliminate direct assessment as the sole integrity assessment method for gas transmission pipelines now because current law authorizes only the Secretary of Transportation to issue regulations prescribing standards for inspection of a pipeline facility by direct assessment. We understand that you intend to address this issue in the pending gas transmission safety NPRM by allowing direct assessment only where pipeline is not capable of inspection by internal inspection tools or where it is not practical to assess using pressure testing or other methods specified, due to low operating pressures and flows, lack of inspection technology, or in such critical delivery areas as hospitals and nursing homes. Pending publication of a final rule that addresses the intent of Safety Recommendation P 15-21, the recommendation is classified OPEN—ACCEPTABLE RESPONSE.

From: PHMSA
To: NTSB
Date: 5/12/2015
Response: -From Timothy P. Butters, Deputy Administrator: The Pipeline and Hazardous Materials Safety Administration’s (PHMSA) mission is to protect people and the environment from the risks of hazardous materials transportation. We are committed to continual improvements to our oversight program to positively influence the safety performance of pipeline operators. PHMSA has a long history of cooperating and collaborating with the NTSB, and we take our responsibility to address all recommendations seriously. Integrity Management (IM) is a performance-based, process-oriented regulatory program developed by PHMSA in response to the Accountable Pipeline Safety and Partnership Act of 1996 (P.L. 104-304), the Pipeline Safety Improvement Act of 2002 (P.L. 107-355), and PHMSA’s oversight experience. Integrity management regulations supplement PHMSA’s prescriptive safety requirements and set systemic performance requirements for operators. IM is based on practices employed by many safety-oriented organizations, whereby safety is continually improved through an iterative process of collecting data, identifying and prioritizing risks, undertaking corrective actions, and assessing performance. We understand that successful implementation of performance-based systems for pipeline safety requires a significant operator commitment to the approach, a diverse set of skills possessed by the operator and regulator that extend beyond pipeline engineering, detailed information on pipeline system and operating conditions, and an understanding of the causes of incidents and near-incidents. For both operators and regulators, the heart of integrity management is to identify the most serious risks through an evaluation of system and incident data, to take data informed corrective action to address risk, and to evaluate program effectiveness and implement new measures based on ongoing assessments of the results. PHMSA is working to improve pipeline safety and the IM program through regulatory development and other means at our disposal. Our Notice of Proposed Rulemaking (NPRM) titled “Pipeline Safety: Gas Transmission,” updating gas transmission pipeline regulations, was recently sent to the Office of Management and Budget (OMB) for review. This NPRM will address many of the NTSB’s recommendations, and we expect it to help pipeline safety by both setting new requirements for operators to follow, and clarifying existing ones. PHMSA’s National Pipeline Mapping System (NPMS) Information Collection was published in the Federal Register on July 30, 2014. We expect the revised Information Collection to lead to improved positional accuracy and address the need for additional pipeline attribute information to support our internal risk models. We believe both of these efforts will be responsive to the NTSB recommendations made in their respective areas. In parallel with our rulemaking and information collection efforts, PHMSA utilizes a variety of non-regulatory approaches to improve pipeline safety and communications. Our public awareness, emergency response training, research and development (R&D), technical workshops, and enforcement programs have helped to advance pipeline safety. For example, since February 2014, PHMSA has conducted seven workshops and public meetings on technical topics such as R&D, cracking, class location, Safety Management Systems, and the National Pipeline Mapping System. PHMSA is also planning a risk-modelling workshop for the summer of 2015 to address the need for operators to move to more sophisticated risk models. Finally, pipeline operators, as owners of the pipeline infrastructure, are required to know and understand their pipeline system operating environments. PHMSA challenges operators to focus on performance and aim beyond the minimum compliance standards established through pipeline safety regulations, to ensure the safety of the public that lives and works around pipelines. Concur in part. PHMSA plans to address this in the in-progress gas transmission safety NPRM, which would allow the use of direct assessment only in instances where the line is not capable of inspection by internal inspection tools or where it is not practical to assess using pressure testing or other methods specified (due to low operating pressures and flows, lack of inspection technology, and critical delivery areas such as hospitals and nursing homes). The NPRM is currently under OMB review, and we expect to publish it in the summer of 2015. PHMSA believes that this will meet the intent of the recommendation. At this time, PHMSA is not able to eliminate the use of direct assessment as the sole integrity assessment method for gas transmission pipelines. The Pipeline Safety Statute, Section 60102, Paragraph M, Inspections By Direct Assessment, states that the Secretary shall issue regulations prescribing standards for inspection of a pipeline facility by direct assessment.