Gas Transmission Integrity Management Flowchart Step 1 Determine

Gas Transmission Integrity Management Flowchart Step 1: Determine Rule Applicability and Identify HCAs ----- Legend ----Analysis/Assessment Data Integration Step 1 Gas operator subject to 49 CFR 192? No Validation Not applicable Communication Class 3 location Yes Class 4 location Class 1 or 2 location with a potential impact radius (PIR) >660 feet and 20 or more buildings intended for human occupancy Does system include transmission lines as defined in 49 CFR 192. 3? Begin: Identify High Consequence Areas (HCAs) Re-evaluate HCAs using new information Determine method to identify covered segments Decision Document all covered segments Method (1) Class Locations PIC containing an identified site Step Method (2) Potential Impact Circle (PIC) PIC containing 20 or more buildings intended for human occupancy 2

Gas Transmission Integrity Management Flowchart Step 2: Threat Identification and Risk Assessment Step 2 Identify threats applicable to covered segments Assemble and integrate all integrity-related information about covered segments Determine method(s) per ASME B 31. 8 S Steps Subject matter expert (SME) Relative risk ranking model Scenario –based model Probabilistic risk model 3, 5, &6 Third-party and outside force damage Cyclic fatigue Perform risk assessment per B 31. 8 S Identify actions to address certain threats Steps Manufacturing and construction defects Corrosion Low-frequency ERW and lap-welded pipe 3, 5, &6

Gas Transmission Integrity Management Flowchart Step 3: Baseline Assessment Plan Step 3 Determine assessment method(s) for each covered segment Inline inspection (ILI) Subpart J pressure test Direct assessment (for EC, IC, and SCC threats only) Other technology Develop direct assessment plan Determine assessment schedule based on identified threats and risk factors Document baseline assessment plan, including methods, schedule, and risk basis Submit 180 -day notification to OPS No Schedule meets rule deadlines? Yes Step 2 Conduct baseline assessments Step 4

Gas Transmission Integrity Management Flowchart Step 4: Remediation Step 4 2 Evaluate assessment results and discover effects within 180 days Immediate repair Implement pressure reduction until repairs complete Complete repairs One-year conditions Evaluation takes longer than 180 days? Yes Document basis for why completion of assessment within 180 days is not practicable No Compare results to remediation criteria to determine appropriate action and repair schedule Other conditions Monitored conditions Re-evaluate during subsequent assessment Develop prioritized schedule for remediation per B 31. 8 S, § 7 Document repair completion date Yes Repairs completed on schedule? No Notify OPS and State/local regulators Provide additional safety through pressure reduction or other action Justify that schedule delay will not jeopardize public safety

Gas Transmission Integrity Management Flowchart Step 5: Additional Preventive and Mitigative Measures Step 5 Identify need for additional preventive and mitigative measures based on identified threats and risk assessment Identify needed enhancements to third-party damage prevention program Identify if outside force damage is an integrity threat and take measures as necessary Identify need for additional automatic shut off valves or remoted control valves Implement additional preventive and mitigative measures Step 2

Gas Transmission Integrity Management Flowchart Step 6: Continual Evaluation and Reassessment Periodically evaluate integrity risk based on data integration and assessment results for all covered segments Step 6 Complete reassessment Step 2 Step 4 Determine reassessment methods Establish reassessment schedule Reassessment interval compliance? Is schedule greater than 7 years? Submit waiver request to OPS to deviate from reassessment intervals (in limited situations) at least 180 days before reassessment deadline or as soon as practicable in cases involving critical supply disruptions Implement confirmatory direct assessment OR low-stress reassessment (This option available only for pipe operating at less than 30% SMYS)