Formate brines Some published milestones 2005 2010 Saudi

Formate brines – Some published milestones 2005 -2010 Saudi Aramco start using K formate to drill and complete (with ESS) in HPHT gas wells 2005 OMV Pakistan start using K formate to drill and complete (with ESS) in HPHT gas wells 2006 First MPD operation in Gravel pack Kvitebjørn with K/Cs with K formate “designer brine in fluid” Statfjord B 2007 2008 Petrobras use K formate brine for open hole gravel packs in Manati field 2009 First of 12 completions in the Kashagan field with K/Cs formate Total’s West Franklin F 9 well (204 o. C) perforated in K/Cs formate brine 2010 K/Cs formate brines used as well perforating fluids in 11 HPHT gas fields in UK North Sea : Dunbar, Shearwater, Elgin, Devenick , Braemar , Rhum, Judy , Glenelg , Kessog , Jura and West Franklin 1999 -2011 Potassium formate from Addcon

Saudi Aramco have been drilling HPHT gas wells with potassium formate brine since 2003 Potassium formate from Addcon

Saudi Aramco use of formate brines, 2003 -2009 • 7 deep gas fields • 44 HPHT wells drilled • 70, 000 ft of reservoir drilled at high angle • 90, 000 bbl of brine recovered and re-used • Good synergy with ESS, also OHMS fracturing Potassium formate from Addcon

Summary from Aramco’s OTC paper 19801 Potassium formate from Addcon

Pakistan - OMV use potassium formate brine for HPHT deep gas well drilling and completions Potassium formate from Addcon

Extracts from OMV’s SPE papers and SPE presentations – note 1, 700 psi overbalance, and 350 o. F Potassium formate from Addcon

North Sea - K/Cs formate brines used as combined HPHT drill-in and completion fluids 33 development* wells drilled and completed in 7 HPHT offshore gas fields • • Huldra (6 ) Tune (4) Devenick (2) Kvitebjoern (8 O/B and 5 MPD) Valemon (1) Kristin (2) – Drilled only Vega (5) * Except Valemon (appraisal well) Mostly open hole stand-alone sand screen completions Potassium formate from Addcon

Tune field – HP/HT gas condensate reservoir drilled and completed with K formate brine, 2002 4 wells : 350 -900 m horizontal reservoir sections. Open hole screen completions. Suspended for 6 -12 months in formate brine after completion Potassium formate from Addcon

Tune wells - Initial Clean-up – Operator’s view (direct copy of slide) June 2003 • • • Wells left for 6 -12 months before clean-up Clean-up : 10 - 24 hours per well Well performance Qgas 1. 2 – 3. 6 MSm 3/d PI 35 – 200 k. Sm 3/d/bar Well length sensitive • No indication of formation damage • • Match to ideal well flow simulations (Prosper) - no skin Indications of successful clean-up Shut-in pressures Water samples during clean-up • Formate and Ca. CO 3 particles Registered high-density liquid in separator Tracer results • A-12 T 2 H non detectable • A-13 H tracer indicating flow from lower reservoir first detected 5 sd after initial clean-up <-> doubled well productivity compared to initial flow data No processing problems Oseberg Field Center Potassium formate from Addcon

Tune – Production of recoverable gas and condensate reserves since 2003 (NPD data) Good early production from the 4 wells - No skin (no damage) 12. 4 million m 3 gas /day - 23, 000 bbl/day condensate Good sustained production - 90% of recoverable hydrocarbon reserves produced by end of Year 7 NPD current estimate of RR: - 18. 3 billion m 3 gas - 3. 3 million bbl condensate Rapid and efficient drainage of the reservoir Potassium formate from Addcon

Huldra field – HPHT gas condensate reservoir drilled and completed with K/Cs formate brine, 2001 • 6 production wells • • 1 -2 Darcy sandstone BHST: 147 o. C TVD : 3, 900 m Hole angle : 45 -55 o Fluid density: SG 1. 89 -1. 96 230 -343 m x 81/2” reservoir sections Open hole completions, 65/8” wire wrapped screens • Lower completion in formate drilling fluid and upper completions in clear brine Potassium formate from Addcon

Huldra – Production of recoverable gas and condensate reserves since Nov 2001 (NPD data) Plateau production from first 3 wells - 10 million m 3 gas /day - 30, 000 bbl/day condensate Good sustained production - 78% of recoverable gas and 89% of condensate produced by end of Year 7 - Despite rapid pressure decline. . . NPD current estimate of RR: - 17. 5 billion m 3 gas - 5. 1 million bbl condensate Rapid and efficient drainage of the reservoir Potassium formate from Addcon

Kvitebjørn field – HPHT gas condensate reservoir drilled and completed with K/Cs formate brine, 2004 -2013 • • 13 wells to date – 8 O/B, 5 in MPD mode 100 m. D sandstone BHST: 155 o. C TVD : 4, 000 m Hole angle : 20 -40 o Fluid density: SG 2. 02 for O/B 279 -583 m x 81/2” reservoir sections 6 wells completed in open hole : 300 -micron single wire-wrapped screens. • Remainder of wells cased and perforated Potassium formate from Addcon

A few of the highlights from Kvitebjoern Fast completions and high well productivity Kvitebjoern well Completion time (days) A-4 17. 5 A-5 17. 8 A-15 14. 8 A-10 15. 9 A-6 12. 7 * Operator comments after well testing (Q 3 2004 ) * Fastest HPHT well completion in the North Sea Potassium formate from Addcon “The target well PI was 51, 000 Sm 3/day/bar This target would have had a skin of 7” “A skin of 0 would have given a PI of 100, 000” “THE WELL A-04 GAVE A PI OF 90, 000 Sm 3/day/bar (ANOTHER FANTASTIC PI)” The Well PI was almost double the target

Kvitebjørn– Production of recoverable gas and condensate reserves since Oct 2004 (NPD data) Good production reported from first 7 wells in 2006 - 20 million m 3 gas /day - 48, 000 bbl/day condensate Good sustained production (end Y 8) - 37 billion m 3 gas - 17 million m 3 of condensate - Produced 70% of original est. RR by end of 8 th year NPD : Est. RR have been upgraded - 89 billion m 3 gas (from 55) - 27 million m 3 condensate (from 22) Note : Shut down 15 months, Y 3 -5 - To slow reservoir pressure depletion - Repairs to export pipeline Potassium formate from Addcon

Economic benefits of using formate brines • SPE 130376 (2010): “A Review of the Impact of the Use of Formate Brines on the Economics of Deep Gas Field Development Projects” • SPE 145562 (2011): “Life Without Barite: Ten Years of Drilling Deep HPHT Gas Wells With Cesium Formate Brine” Potassium formate from Addcon

Economic benefits from using formate brines - Good well performance and recovery of reserves • “High production rates with low skin” * • “ We selected formate brine to minimise well control problems and maximise well productivity”* * Quotes by Statoil relating to Kvitebjoern wells (SPE 105733) Potassium formate from Addcon

Economic benefits from using formate brines - More efficient and safer drilling Better/safer drilling environment saves rig-time costs • Stable hole: see LWD vs. WL calipers in shale • Elimination of well control* and stuck pipe incidents • Good hydraulics, low ECD • Good ROP in hard abrasive rocks * See next slide for details “ a remarkable record of zero well control incidents in all 15 HPHT drilling operations and 20 HPHT completion operations” Potassium formate from Addcon

Economic benefits from using formate brines - Improved well control and safety • Elimination of barite and its sagging problems • Elimination of oil-based fluids and their gas solubility problem • Low solids brine Low ECD (SG 0. 04 -0. 06) and swab pressures • Inhibition of hydrates • Ready/rapid surface detection of well influx • Elimination of hazardous zinc bromide brine Potassium formate from Addcon

Economic benefits from using formate brines - More efficicient/faster completions - Drill-in and completing with formate brine allows open hole completion with screens - Clean well bores mean no tool/seal failures or blocked screens - Completion time 50% lower than wells drilled with OBM “ fastest HPHT completion operation ever performed in North Sea (12. 7 days)” Potassium formate from Addcon

Economic benefits from using formate brines - Operational efficiencies Flow check fingerprint for a Huldra well Duration of flow back (minutes) Fluid Gain (bbl) • No differential sticking • Pipe and casing running speeds are fast 30 0. 8 • Mud conditioning and flow-check times are short 15 0. 56 20 0. 44 30 0. 56 • Displacements simplified, sometimes eliminated Potassium formate from Addcon

Economic benefits from using formate brines - Good reservoir definition if Cs present in fluid • • High density filtrate and no barite Filtrate Pe up to 259 barns/electron • Unique Cs feature - makes filtrate invasion highly visible against formation Pe of 2 -3 b/e • LWD can “see” the filtrate moving (e. g. see the resistivity log on far right – drill vs ream • Good for defining permeable sands (see SAND-Flag on log right ) • Consistent and reliable net reservoir definition from LWD and wireline Potassium formate from Addcon

Economic benefits from using formate brines - Good reservoir imaging • • conductive fluid Highly Clear resistivity images • Information provided: - structural dip - depositional environment - geological correlations Potassium formate from Addcon

Formate brines – Summary of economic benefits provided to users Formate brines tend to improve oil and gas field development economics by : • Reducing well delivery time and costs • Improving well/operational safety and reducing risk • Maximising well performance • Providing more precise reservoir definition Potassium formate from Addcon

Formate brines as packer fluids in GOM BHT (°C) BHT (°F) Start Date 8. 6 KFo 149 300 1/2005 WC 165 A-8 8. 6 KFo 149 300 1/2006 Devon WC 575 A-3 ST 2 9. 5 KFo 132 270 5/2005 WOG/Devon MO 862 #1 12. 0 Na. KFo 215 420 4/2005 5/2006 Well P&A – H 2 O production – G-3 in excellent condition BP/Apache HI A-5 #1 11. 5 Na. KFo 164 350 2/2002 4/2008 Well P&A - Natural depletion – S 13 Cr in excellent condition Exxon. Mobil MO 822 #7 12. 0 Na. KFo 215 420 2001 EPL ST 42 #1 11. 5 Na. KFo 133 272 2006 EPL ST 41 #F 1 13. 0 Na. KFo 105 222 2006 EPL EC 109 A-5 11. 5 Na. KFo 121 250 2006 EPL ST 42 #2 12. 8 Na. KFo 132 270 2006 Dominion WC 72 #3 BP 1 10. 0 Na. Fo 121 250 2006 EPL WC 98 A-3 ST 1 12. 7 Na. KFo 153 307 2006 EPL WC 98 A-3 10. 8 Na. KFo 154 310 2007 OPERATOR LOCATION Devon WC 165 A-7 Devon Potassium formate from Addcon Packer Fluid (ppg) End Date Comments

BP High Island – Na/K formate brine as packer fluid for 6 years • • 177ºC, 14, 000 psi • Well worked over and recompleted with Cs formate • 1. 4 g/cm 3 Na/K formate used as packer fluid • Tubing retrieved 6 years later • Tubing was in excellent condition. S 13 Cr tubing failed from Ca. Cl 2 packer fluid Potassium formate from Addcon