Dynamic SettlingStability Workgroup Summer 2013 Robert Beirute Beirute

Dynamic Settling/Stability Workgroup – Summer 2013 Robert Beirute, Beirute Consulting; Heath Williams, Schlumberger; Paul Sonnier and Jeff Watters, CSI, Deryck Williams, Chevron. Texaco; Greg Garrison and Katrina Price, OTC; Graeme Anthony, OFIte June 25 th, Houston, TX

Schlumberger Confidential Agenda 1. Minutes of Previous Meeting and Action Items 2. Overview of Workgroup objectives/progress 3. Procedures to run dynamic vs. static testing for Workgroup 4. Summary of API Cooperative test results 5. Our roadmap moving forward 2

Schlumberger Confidential Minutes of Previous Meeting TG on Test Methods for Determination of Dynamic Settling • Several task group members were present. • Meeting Minutes for January 22 nd, 1: 15 pm held at the Intercontinental New Orleans, LA • Review of testing conducted so far which included a hematite system that failed both the dynamic settling and free fluid testing, and the spacer system which passed both the dynamic and free fluid test. • A system that passed both free fluid and DST • A system that will pass the free fluid but fail the DST is still being designed • The chairman made the comment that static settling has the potential to develop gel strengths which can aid in stability whereas dynamic settling does not allow for development of the gel strength. Action Items • After much discussion it was decided to pursue the development of Designs 1 and 2 • Continue the round robin testing for the next meeting in the summer. • Designing system for round robin testing that passes static criteria and fails dynamic criteria • Updating the procedure to include the syringe method for taking the density readings of top, middle and bottom. • Update the procedure to include the weighing of the paddle before and after the test. 3 Indicates Action Items that have been completed

Completion/Progress and Projected Timeline 06 -2011 01 -2012 Explored DST alternatives Phase 1 – showed systems that passed/failed Static and DST Phase 2 – cement failed DST but passed static Phase 2 – Updated procedures and begin technical report Phase 3 - Submit report/procedures for comments and review from DST Workgroup Phase 4 - Submit report/procedures for comments and review from SC 10 Phase 5 - Final report/procedures ratified by SC 10 06 -2012 01 -2013 06 -2013 01 -2014 06 -2014 Schlumberger Confidential % Workgroup Completion Timeline (2012 -2015) 100% 80% 60% 40% 20% 4 0%

Objectives for Phase 2 Testing Schlumberger Confidential § Test a cement system that would show unique value of DST for performance-based cement stability evaluation o 1. Pass GO/NO testing with minimal increase in BC (less than 50 BC) o 2. Pass free fluid criteria with less than 1% free fluid. o 3. Pass sedimentation test criteria with less than 5% settling o 4. Fail DST criteria with more than 5% change in density trend measured down the length of the slurry HPHT cup after DST testing o 5. Fail DST cone height measurements (greater than 0. 5 inch in height) § Add test procedures and interpretation guidelines o Define motor speed at 25 rpm o Ramp to BHCT following well schedule, Stabilize for at least 30 min, Turn motor speed to 25 rpm for 30 min, Shutoff 5 motor ensure lab to lab uniformity in low shear exposure

Previous version(s) Updated version Motor speed was varied between 25 -35 rpm, depending on procedure 25 rpm is locked as the one motor speed Motor speed was left at 25 -35 rpm for at least 20 min period and cool-down period also Motor speed is left at low shear for at least 30 minutes and then the motor is shut down before cool-down period No attempt was made to quantify under and over-dispersion with DST Attempt is made to quantify under and over-dispersion with DST with simple mathematical relationship No density trend with syringes 10 -m. L tared syringes used to collect from upper, middle, and lower thirds of slurry cup Only center cone height used as consideration Center, ½ radius or middle, and radius or outside positions are used in mathematical relationship = %deg dispersion = (center cone height-outside cone height)/center cone height x 100% Schlumberger Confidential Phase 2 – Updated DST Procedure and comparison with older versions of procedure 6

Schlumberger Confidential Link to DST, GO/NO GO – Free Fluid, and Sedimentation Updated Procedures Unpacking List. Unpacking List and Dynamic Weigh Out Sheet _CD_RHW_15 Ma DST Procedure Dynamic Settling Test Procedure _ Ramp up to 350 deg. F. docx GO/NO and Free Fluid Procedure Free Fluid Test after Conditioning in HPHT Consistometer_15 May 2013. docx Sedimentation Test API Sedimentation Test. docx 7

Workgroup Cooperative Testing Summary Workgroup Members WG WG WG 3 1 WG 4 WG 5 Ave 2 BHCT (deg. F) STDe v GO/NO GO Init/Max BC NA 12/7 24/28 4/8 15/33 12/23 7/13 Free Fluid (%) NA 0 0 5 1. 3 1. 6 2. 4 FF Angle (deg) NA 45 45 45 NA Sedimentation. Test (max dev. ) (%) NA 3. 0 1. 7 NA 0. 5 1. 7 1. 3 Yes Yes - DST – dens top 1/3 rd (lbm/gal) 15. 4 15. 9 15. 2 14. 5 13. 7 14. 9 0. 9 DST - dens mid 1/3 rd (lbm/gal) 16. 7 17. 2 16. 2 17. 6 16. 8 16. 9 0. 5 DST – dens bott 1/3 rd (lbm/gal) NA 16. 9 16. 7 18. 2 16. 9 17. 2 0. 7 % difference density top-bottom 8. 4 0 9. 9 25. 5 23. 4 14. 7 9. 0 1 1. 5 1. 3 0. 3 Cone height – 1/2 R or middle (in. ) 0. 63 1. 5 1. 1 0. 8 1. 3 1. 1 0. 4 Cone height – R or outside(in. ) 0. 31 1. 4 1. 0 1. 1 1. 0 0. 4 69 6. 7 9. 1 33. 3 26. 7 29. 0 25. 1 Static Slurry Stability Achieved? Cone height – center (in. ) Degree of dispersion (%)* Schlumberger Confidential 350 1 STD 2 STD DST Slurry than Stability * Greater 50%Criteria difference between. No center. No and outside height indicates No cone. No No No Achieved? ** 8 underdispersed slurry ** Less than 50% difference and cone height less than 0. 5 in. for any measurement location is stable

Schlumberger Confidential GO/NO GO Test Results 9

GO/NO test observations after pulling paddle CSI Schlumberger Confidential SLB OTC 10

SLB CVX Schlumberger Confidential Free fluid observations after conditioning in GO/NO GO test and 2 hrs at ambient temp as per API RP 10 B-2 CSI OFIte 11

Schlumberger Confidential DST consistency behavior during motor speed at 25 rpm 12

DST cone observations after revised DST procedure and removing modified paddle CSI OTC CVX OFIte Schlumberger Confidential SLB 13

Schlumberger Confidential Conclusions 14

• Collect more cooperative data from workgroup members • Look at alternative ways of describing dispersion (slope of cone using Pythagorean theory? ) • Write technical report/RP for workgroup input and comments • Submit workgroup-validated report/RP to SC 10 for input and comments • Submit technical report/RP to SC 10 for vote/ratification Schlumberger Confidential Our Roadmap… 15

Schlumberger Confidential Questions from the Audience 16