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RAILROAD COMMISSION OF TEXAS
Stephanie WeidmanAustin Regional Manager
Oversight and Safety DivisionPipeline Safety
September 2015
Gas Transmission Integrity Management Programs
Lessons Learned
Session Overview
• The early days of integrity
• Where are we now?
• What to expect later down the road?
Integrity Management
Overview– Over 298,000 miles of onshore transmission lines
in US
– Approximately 107,000 miles are intrastate
– Approximately 32,000 miles are located in Texas
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The Early Days
• Integrity Management Rule effective December 2004
• We are now over 10 years in
• All pipelines have at least one assessment
• Major gas incidents still occurring
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NTSB Safety Study
• NTSB Safety Study published January 27, 2015– http://
www.ntsb.gov/safety/safety-studies/Pages/SafetyStudies.aspx
• NTSB performed study due to NTSB’s involvement in three major gas incidents in the last six years where deficiencies with operator’s IM programs were identified as concern
• Study resulted in 28 new recommendations 6
NTSB Recommendations
• Of the 28 new recommendations– 22 are addressed to PHMSA– One to the National Association of Pipeline Safety
Representatives (NAPSR)– One to the Federal Geographic Data Committee
(FGDC)– Two to the American Gas Association (AGA)– Two to the Interstate Natural Gas Association of
America (INGAA)
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NTSB Recommendations
HCA Identification Processes• P-15-7 and P-15-28
– To PHMSA and FGDC– Create standards for geospatial data used in
industry– develop a national repository of geospatial data
resources to use in HCA identification.• P-15-6
– Address limitations of current HCA identification processes
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NTSB RecommendationsImproving Data Collection and Reporting• P-15-5, P-15-15, P-15-16 and P-15-19
– Updates to Form F7100.1 to include:• HCA methods used• Risk assessment approaches used• Total mileage (HCA/non-HCA) smart piggable pipelines
– Updates to Form F7100.2 to include:• Previous assessment results • Previously identified threats • Multiple Root causes when threats interact
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NTSB RecommendationsGuidelines for Eliminating Threats• P-15-9
– Establish minimum criteria for eliminating threats– Provide guidance for documenting rational for all
eliminated threats. – ASME B31.8S Section 5.9 Data Collection for Risk
Assessment outlines minimum criteria to eliminate a threat
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NTSB Recommendations
Guidelines for Interactive Threats• P-15-10
– Establish a list of all interactive threats that must be evaluated.
– Establish a list of all assessment methods to be used
– ASME B31.8S Section 2.2 Integrity Threat Classification: States interactive threats shall be considered
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NTSB RecommendationsGuidelines for Risk Assessment Approaches• P-15-12, P-15-13
– Weigh safety benefits of the four risk assessment approaches and determine if they produce comparable safety benefit
– Updated guidance on critical components of risk assessment approaches including:
• Methods for setting weighting factors• Factors included in consequence of failure calculations• Appropriate risk metrics
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Guidelines for Risk Assessment Approaches (Cont’d)• P-15-23, P-15-25
– Recommendations to AGA and INGAA– Collect data that supports development of probabilistic
risk assessment models• Probabilistic Risk Assessment Model
– Most complex approach– Demanding data requirements—data integration
• NTSB Recommendation P-11-14– Advisory Bulletin 2012–06: Integrity Verification Process (IVP)
• NTSB Recommendation P-15-22: Develop and implement plan to improve data integration through use of GIS
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NTSB Recommendations
Guidelines for Risk Assessment Approaches (Cont’d)• Probabilistic Risk Assessment Model
– Most complex approach– Demanding data requirements—data integration
• NTSB Recommendation P-11-14– Advisory Bulletin 2012–06: Integrity Verification Process (IVP)
• NTSB Recommendation P-15-22: Develop and implement plan to improve data integration through use of GIS
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NTSB Recommendations
• Majority of recommendations call to gather data to :– Create threat elimination guidelines– Create interactive threat guidelines – Create risk assessment approach guidelines
• What are we going to do with these guidelines and data?
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NTSB RecommendationsCreate Study and Develop Program• P-15-17
– Develop program to use data collected to evaluate relationship between incident occurrences and:
• Inappropriate elimination of threats• Interactive threats• Risk assessment approaches
• Now that we have this data, how should we assess the pipeline?
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NTSB RecommendationsIn-line Inspection Capabilities• P-15-18
– Repeat of P-11-17– Requires ALL gas transmission lines be smart piggable
• Reconfigure pipeline• New technology permitting inspection of uninspectable
lines
• P-15-20– Identify operational complications that limit the use of ILI
tools in piggable lines– Develop methods to eliminate the operational
complications and require operators to use these methods
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NTSB Recommendations
In-line Inspection Capabilities (Cont’d)• P-15-24 and P-15-26
– To AGA and INGAA– Develop and implement strategy for increased use
of ILI tools, specifically on intrastate pipelines• Safety Study noted:
– “…96% of assessed interstate pipeline mileages were inspected by ILI, while ILI was used for only 68% of assessed intrastate pipeline mileages.”
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NTSB Recommendations
Anomalies Repaired (per 1,000 miles)
Assessment Tool Assessed Interstate Pipelines
Assessed Intrastate Pipelines
Average for All Assessed Pipelines
In-line Inspection 649 709 663
Pressure Test 21 46 35
Direct Assessment 86 307 264
Other Techniques 11 27 26
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Assessment method vs. Anomalies Repaired
NTSB RecommendationsEliminate Direct Assessment as sole method• P-15-21
– Eliminate the use of direct assessment as sole integrity assessment
– Safety Study noted:• “…The corrosion threat was highly prioritized by the
operators in their relative risk calculation to justify the use of direct assessment.”
• “…Operator’s primarily use only one integrity assessment method to assess the physical integrity of their HCA pipelines.”
– 192.917 An operator must identify and evaluate all potential threats to each covered pipeline segment.
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NTSB RecommendationsLimitations to Direct Assessment
1) Limited to the detection of defects attributed to corrosion threats
2) Only covers very short sub-segments of the pipeline3) Relies on the operator’s selection of specific
locations for excavation and direct examination4) Yields far fewer identifications of anomalies
compared to ILI.
In comparison, ILI and pressure testing assess the entire pipeline segment and are capable of detecting defects associated with multiple threats.
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NTSB RecommendationsAs a whole the recommendations: • Call to gather data to create standard
guidelines
• Call for guidelines that push operators to obtain more information about their system
• Call for using methods that give operator’s more information about their systems
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NTSB Recommendations
• Data Verification
• Data Integration
• More Complex Risk Assessment Model
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Significant Safety Study Conclusions
• HCA incidents attributed to causes other than corrosion and material defects in pipe/weld increased from 2010–2013
• From 2010–2013, the intrastate gas transmission pipeline HCA incident rate was 27% higher than interstate.
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Significant Safety Study Conclusions
• In-line inspection is able to inspect the integrity of the pipeline segments susceptible to multiple threats.
• Of the four assessment methods, in-line inspection yields highest per-mile discovery of anomalies
• Use of direct assessment as sole integrity assessment method must be subject to strict scrutiny by the inspectors due to its numerous limitations.
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RRC IMP Inspections
• Most common issues– Failure to have procedures outlining a process– Failure to justify unknowns and elimination
threats– Failure to justify assessment methods.– Failure to justify reassessment intervals– Failure to implement/document P&M measures– Lack of program ownership (contractor use)
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Contact Information
Questions??
Stephanie Weidman
Austin Regional Manager
512-463-2519
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