Drill Well presentation 4th Sept 2008Havila Harmony operations

2008 NWS Severance campaign

DRIMS #4402418, Author Simon Glennie, DrillWell Sept 08 3

Selected wells :

Abandonment Well Review

Cossack-2

Cossack-3

Wanaea-5

Echo-1

Yodel-1

Goodwyn-9

Adequate subsurface barriers in place so that

severance of the wellhead suffices to complete

the abandonment.

No value associated with re-entry for data

acquisition purposes

All wells meet following criteria :

DRIMS #4402418, Author Simon Glennie, DrillWell Sept 08 4

Equipment overview

The Havila Harmony was mobilised for the North West Shelf Severance campaign out of King Bay Supply Base, Dampier.

The vessel sailed out to location on the 4th June 2008.The AXE severance system has a

proven track record

The operations were delayed on numerous occasions by weather, NPT and many unforseen challenges caused from marine growth and limited well information.

DRIMS #4402418, Author Simon Glennie, DrillWell Sept 08 5

Severance Timing Charts

NWS Severance Location Breakdown

Echo 1Goodwyn 9Yodel 1Wanaea 5Cossack 2Cossack 3

Cleaning operations

0

5

10

15

20

25

Cleaning ops

Echo 1Goodwyn 9Yodel 1Wanaea 5Cossack 2Cossack 3

Wellhead Cap Removal

0

5

10

15

20

25

30

Locations

Hou

rs

Echo 1Goodwyn 9Yodel 1Wanaea 5Cossack 2Cossack 3

Cutting operations

0

5

10

15

20

25

Severance

Locations

Hour

s

Echo 1Goodwyn 9Yodel 1Wanaea 5Cossack 2Cossack 3

DRIMS #4402418, Author Simon Glennie, DrillWell Sept 08 6

Cleaning operations

A total of 33.5 hours was spent cleaning marine growth from the wellhead caps and conductor housings in preparation for tooling deployment.

A purpose built ROV cleaning tool was mobilised specifically for cleaning the vent ports on the 30”conductor housing.

Various methods were utilised for blocking the vent ports in the 30” conductor housings, cement was used in the Cameron style and magnetic plugs were trialled on the FMC and Vetco styles. These were subsequently changed out for a more robust hydrostatic style of plug.

DRIMS #4402418, Author Simon Glennie, DrillWell Sept 08 7

Wellhead Cap Recovery

There were 3 different styles of wellheads and caps, (Vetco, Cameron and FMC). The Cameron style cap in the picture was fitted with shear pins rated to 50,000lbs.

The caps were originally installed using a “J” slot running tool.

The “J” slot running tool was used in conjunction with a bumper sub in an attempt to recover the wellhead caps, load applied to the tool was around 36T, due to marine growth the caps refused to come off using this method.

DRIMS #4402418, Author Simon Glennie, DrillWell Sept 08 8

Wellhead Cap Removal

Due to the problems encountered with the cap removal a purpose built jacking assembly was manufactured to fit the FMC style caps.

The jacking tool had to be modified whilst offshore to fit the Cameron Style caps.

The jacking tool was successfully deployed and wellhead caps were recovered from all of the wellheads.

The maximum pressure applied to the tool was 1500psi, this equated to a force of 84.6T for the to release.(Well above the figure of 50,00lbs = 22.6T)

DRIMS #4402418, Author Simon Glennie, DrillWell Sept 08 9

Yodel-1 removed

Plenty of marine life around !

Bigfoot TGB, weighs ~36ton

Yodel well head recovery

Severed casings

DRIMS #4402418, Author Simon Glennie, DrillWell Sept 08 10

Cost v Budget

Initial mobilisation, transit and demobilisation fees managed within budget

Severance trend shows learning's incurred on first wells

Left chart shows severance cost detail

Downward trend for all activities through completion of campaign

Note 26% weather downtime

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

4.5

AFE perwell*

Echo-1 Yodel-1 Goodwyn-9 Wa-5 Ck-2 Ck-3

A$M

Initial mob fee Transit/mob/demob Severance cost

0.0

0.5

1.0

1.5

2.0

2.5

3.0

Echo-1 Yodel-1 Goodwyn-9 Wa-5 Ck-2 Ck-3

A$M

WoW NPT Clean wellheadRemove cap Drift casing Cement/plugCut wellhead Recovery Future recovery

DRIMS #4402418, Author Simon Glennie, DrillWell Sept 08 11

Current Status

The wellheads at Echo 1, Wanaea 5, Cossack 2 and Cossack 3 have now been severed but require more than 35T to pull the wellheads clear from the sea bed. Unable to complete due to crane control system fault which limited pull to 35t

The wellheads from Yodel 1 and Goodwyn 9 were successfully recovered to surface.

Remaining wellheads now removed using anchor handler to unseat from seabed working in tandem with the Havila Harmony,

“SERPENT” project on board, this study collects, research

information and samples, end result may be non recovery of

wellheads under some circumstances

Rigless Tree deployment and Intervention

DRIMS #4402418, Author Simon Glennie, DrillWell Sept 08 13

Rigless Intervention Capability

What have we done so far -

7 of Subsea trees deployed, installed and tested successfully

7 “shallow” wireline runs to pull hanger plugs successful

4 “deep” runs to pull prong/plug successful (max ~1400 metres)

4 of Formation Isolation Valves cycled open

All wells handed over ready for operation weeks ahead of requirement

DRIMS #4402418, Author Simon Glennie, DrillWell Sept 08 14

How did we do it - Mobilisation

Significant logistical operation, as can be seen from the before and after photographs there was a large amount of equipment to be installed and sea fastened to the vessel. The large “frame” is the VDS, this in conjunction with a 50 ton heave compensated winch is used to deploy and recover the subsea intervention system through the vessel moonpool.

Around 60 trucks and 2 cranes were used in the mobilisation of all this equipment from Perth and Karratha. None of the equipment had ever been installed on the vessel before and resolving interface issues and providing a safe working area for personnel was a considerable challenge.

DRIMS #4402418, Author Simon Glennie, DrillWell Sept 08 15

Deployment of Xmas trees

Conventionally an Xmas tree would be run from a drilling rig using rigid riser and a hydraulic umbilical to supply locking and testing capability. This can take a significant amount of time especially in deeper water.

From the Havila Harmony the Xmas tree was run using a simple mechanical tool and the vessel 150ton active heave compensated crane. Locking and testing capability were supplied by the vessel ROV fitted with a specially developed hydraulic power pack and tooling. This method gave a greatly simplified running procedure and the all components of the developed system can be used in water depths up to 2000 metres.

DRIMS #4402418, Author Simon Glennie, DrillWell Sept 08 16

Well Intervention

Well InterventionOn completion of the Xmas tree installation the vessel intervened on the wells. 12 wireline runs

were completed to a maximum depth of 1400 metres, each successfully pulling a wireline plug, in 4 of the wells a Formation Isolation Valve was also opened.

This intervention was completed using a newly developed WellOps SEA Subsea Intervention system which unlike traditional rig based methodology does not require a riser to extend from the seabed to surface. Instead the pressure control equipment required to intervene on the wells is installed directly on the Subsea tree.

This was technically the most challenging aspect of the campaign, although significant integration testing had been carried out prior to mobilisation none of the components had been used operationally or even been subsea before. The first deployment and successful operation was completed in a water depth of 372 meters.

Subsea intervention device being deployed through moonpool

ROV guiding wireline toolstring into subsea lubricator

Subsea intervention device on top of EVXT during SIT

DRIMS #4402418, Author Simon Glennie, DrillWell Sept 08 17

Well Intervention

DRIMS #4402418, Author Simon Glennie, DrillWell Sept 08 18

Times for Tree installation

10.75 35.75 17 12.5 8 8.75 9.75 7.5

0

5

10

15

20

25

30

35

40

Hours

From surface to test

Xmas tree installation & test

Tech Limit W3 W2 G1 H3 H4 H2 H1

DRIMS #4402418, Author Simon Glennie, DrillWell Sept 08 19

Times for unplugging the wells

45 175 118.5 86.5 59.25 33.25 32 27.75

0

50

100

150

200

Hours

1Times from surface to surface

Un-plug well / open FIVTech Limit G1 W2 W3 H3 H4 H2 H1

DRIMS #4402418, Author Simon Glennie, DrillWell Sept 08 20

Rigless Intervention, how did we get there

Full SIT, no time or budget restraint, only stipulation was to get it right, It took 4 weeks & cost >$1M but was worth it. All major NPT issues were as a result of untried/untested items, SIT was dry !Wet trial of Intervention equipment prior to deployment on 1st well.Had several “install tree on paper” sessions with relevant personnel, ultimate solution significantly different and easier than original planDedicated FMC engineer from 4 months before campaign startedOffshore supervision all involved in preparation from at least 3 months prior to mobilisationOffshore supervision, same people from beginning to end.Dedicated HSE coachConsistent WEL project management team, allowed quick decision making.Working with SOG and Vincent project team facilitated “break” in campaign, this allowed numerous system improvements to be made for 2nd campaign.

DRIMS #4402418, Author Simon Glennie, DrillWell Sept 08 21

Rigless Intervention, achievements so far–

First deployment and installation of Subsea Xmas trees from a vessel in this regionDevelopment of a robust and reliable method of deploying, installing and testing Xmas trees in water depths up to 2000 metres.First subsea well intervention in this region, 4 wireline runs completed with 100% success rate, deepest to 4634ft. First time the WellOps subsea intervention system has been deployedFirst time the Havila Harmony and TS Marine have deployed trees or completed subsea interventionThe unofficial “world record” for subsea wireline intervention is believed to be 377mtr. Woodside have in their first ever subsea intervention achieved 2nd place at 372 mtrs. Project integration, the Havila Harmony also used for project construction and commissioning activities in between well intervention duties. Most importantly the campaign was completed without harm to personnel or the environment. All HSE leading and lagging indicators have significantly exceeded corporate and D&C targets. Only a handful of personnel involved had any experience of this type of operation and it is a considerable achievement to complete it with such an outstanding HSE performance.(subsequent to this had LTI during well severance campaign)

DRIMS #4402418, Author Simon Glennie, DrillWell Sept 08 22

Rigless Intervention Overview

Who did what -

TS Marine – Havila Harmony operator and main contractor, supply of vessel and ROV’s, project engineering and management of sub-contractors. Supply of ROV and supervisory personnel.

WellOps SEA – Subcontractor to TSM, supply of VDS system, subsea intervention system and AXE well severance system. Specialist personnel to operate equipment.

FMC, supplied trees and interface control system. Dedicated engineer & offshore personnel

Schlumberger – Wireline equipment, pumping equipment and bleed off package. Personnel offshore