Plug & Abandonment Forum (PAF)

P&A in the past, present & in the futurePAF Seminar 29 October 2015

Martin Straume, chairman PAFLead P&A engineer, BP Norge

2

Topics

1. P&A in the past

2. P&A at the present

3. P&A in the future – PAF

4. Future technology - P&A roadmap

5. Summary

P&A in the pastBest field P&A in Norway

• P&A Frigg with average of 5,3 days/well

• Wells P&A-ed with Mærsk Innovatorduring 2003 (1st campaign) and 2005

(2nd campaign)

• Drilling of these wells finished in 1979

• Wells designed with cemented casing fromcasing shoe to inside previous casing shoe

• Much of the P&A work was to set internalcement plugs

3

4

P&A at the presentWell design changed at some point at NCS

• Directional wells, Longer wells, HPHT wells

• Primary cementing from casing shoe to 200mabove the casing shoe

• Open annulus from TOC and into previouscasing shoe

• New overburden knowledge may dictatebarriers where no cement is

5

Knowing our overburden

• Today, we have better technology and tools to map the overburden sealscompared to the past

• Therefore - well design today could include annulus barriers in new wells where seals need to be at the time of P&A – some time in the future

• Some North Sea fields have swelling shales which seal after being drilledthrough. If they swell, or can be promoted to swell, new well design could plan for shale barrier at P&A time. Cap rock……………..

• Include P&A barrier schematics in drilling program

• Aim for P&A to become installation of internal barriers

• Think ”Cradle - to – Grave” when constructing new wells

6

• With external casing barriers in place,……

• Wireline and coiled tubing can log,

set bridge plugs, set cement plugs, etc..

• Possible to cement A-annulus through tubing

• If we only could log 2 strings….…missing link

• Could delay rig P&A to the 13 3/8” shoe

• Rigless P&A has well control equipm. in place

• Rigless P&A gives flexibility in timing for P&A

P&A in the futureRigless P&A ?

7

Plug & Abandonment – Technology

• Conventional P&A – yes• What’s new?• Shale Barriers• Perf – Wash – Cement technology

Roadmap for New P&A Technologies

8

Optimize Perf Wash & Cement

Optimize Milling

Rigless P&A- High Capacity CT System- High Energy Solutions

(Melt/Burn)/Extreme Concept

Alternatives to cement- Creeping shale / Formation

effects- Sand/Rock/Natural

materials- Chemical materials- Steel

Improved Verification / Logging methods

Wireless technology(subsea wellheads)

Tubing left in hole

Ctrl line left in hole

Dual string: Cement bond logging Perf, Wash & Cement, Milling

Well Intervention technologyfor P&A

Tender Support P&A rigs/Modular Rigs

LIV CT Pilothole drilling/cementing

Rig/Process optimization

Drill Pipe Coil Tubing Through Tubing Wireline Rigless

2015 2016 2017 2018

Focus areas for 2015 - 2016 Futuristic Technologies

9

Summary

1. Cradle to Grave well design. Design new wells to let P&A become internal barriers the next 40 yrs.

2. Make use of mother earth if possible (shale swelling). Best long term testedbarrier ever.

3. Key missing technology is logging through 2 strings.Verification of external barriers.

4. Potential to leave tubing in the hole.

5. More scope to rigless P&A could enable more flexibility around when rig P&A takes place.

6. Rigless P&A through X-mas tree keeps well control equipment in place.

7. P&A needs new technology to place quality barriers at reduced time and cost. Win – win for the industry and the nation.