Underground Natural Gas Storage

Transcription

1 Underground Natural Gas Storage A Pragmatic Approach to PHMSA s IFR and Risk Assessment Chris Foley Vice President

2 Overview 1. Historical Perspective of Storage Incidents 2. New PHMSA IFR Requirements 3. Risk Analysis Potential Pit Falls 4. Building Blocks For Compliance With IFR Gap Analysis Process Development and Improvement Risk Analysis Integrity Assessment/Tracking Remediation

3 April 1992 Brenham TX, salt cavern HVL release & explosion July 1997 PHMSA Advisory Bulletin 97-04; Underground Storage of Natural Gas or Hazardous Liquids August 2004 Moss Bluff TX, natural gas storage cavern uncontrolled release and fire July 2015 API RP 1170 Design and operation of Solution-mined Salt Caverns Used for Natural Gas Storage October February 2016 Porter Ranch CA, Aliso Canyon Natural Gas reservoir gas leak June 2016 PIPES Act 2016, Section 12 Underground gas storage facilities October 2016 Interagency Task Force on Natural Gas Storage Safety: Final Report, Ensuring Safe & Reliable Underground Natural Gas Storage February 1995 IOGCC, Natural Gas Storage in Salt Caverns, A guide for state regulators. January 2001 Hutchinson KS, natural gas salt cavern leak and explosions October 2006 Fort Morgan CO, natural gas storage reservoir leak September 2015 API RP 1171 Functional Integrity of Natural Gas Storage in Depleted Hydrocarbon Reservoirs and Aquifer Reservoirs February 2016 PHMSA Advisory Bulletin , Safe Operation of Underground Storage Facilities for Natural Gas July 2016 CA DOGGR Draft Article 4. Requirements for Underground Gas Storage Projects December 2016 PHMSA Interim Final Rule; Safety of Underground Natural Gas Storage Facilities

4 Potential Pitfalls 1. Can t See the Forest For The Trees Syndrome - you might not realize that a branch of separate trees go together to make a forest 2. Draining the Swamp Syndrome drain the swamp means to exterminate something that is harmful (in this case risk) 3. Trust But Verify Syndrome extensive verification procedures that would enable both sides to monitor compliance with the treaty

5 Building a Risk Model What s the Objective? 1. Types of Models 2. Critical Issues and Drivers 3. How much do we know and how well do we know it? 4. Feeding the beast

6 PHMSA IFR Building Blocks for Compliance

7 Gap Analysis 1. Standards or Procedures Shall (125) Should (250+) May (50+) 2. Storage Integrity Plan Overarching Plan focus on how to 3. Risk Management Plan Describes how you will assess and manage risk

8 Process Development and Improvement Storage Risk Management Plan Site-Specific Operations & Integrity Standards

9 Risk Model Category Elements 1. Wells (subsurface) Challenging to Asses Integrity but well Developed Technology is Available 2. Reservoir (facility) Most Challenging to Assess Integrity but Combination of Technology and Industry Accepted Methods 3. Surface (Wellhead and near wellhead piping) Relatively easy to assess can see, touch, and measure directly

10 Threats and Consequences 1. Threats Grouped According to Elements listed in Table 1 of API 1171 Include concerns which can be assessed with existing methods, tools, and technology Site-specific issues 2. Consequences Comprehensive list outlined in API 1171 Challenge is how to characterize continuum of outcomes 3. Threats and Consequences Should be weighted to differentiate potential impacts

11 Output Yields a Risk Score 1. Relative Ranking Allows Prioritization of P&M Measures Wells Well Specific Reservoir Facility Basis Surface Well Specific 2. Consequences Comprehensive list outlined in API 1171 Challenge is how to characterize continuum of outcomes

12 Graphical Output

13 Integrity Assessment and Tracking Years to Complete Process Baseline Assessments Size Dependent Existing Baseline Assessments May be Used* Periodic Review and Update of Risk Assessment Ongoing Review of Standards 2. Plan will likely Evolve New Information will alter initial priorities

14 Remediation Progress Tracking Years to Complete Process Baseline Assessments Size Dependent Existing Baseline Assessments May be Used* Periodic Review and Update of Risk Assessment Ongoing Review of Standards 2. Auditable Process Close Out of Remediation Efforts Record Keeping Training

15 Questions? Chris Foley (713)