Cuadrilla Bowland Limited Notification of Intent to Drill ......The drilling rig to be used is...

Cuadrilla Bowland Limited

Notification of Intent to Drill Preston New Road 1 & 1Z on LJ/06 Particulars Required for Notification under Regulation 6(1) of BSOR

Contents

1.0 Name and Address of the Operator 2

2.0 Particulars of the Type of Well 2

3.0 Particulars of the Rig and Plant 4

4.0 Particulars of Surface Equipment and Fluids to Control Well Pressure 6 4.1 Surface Equipment: Well Control During Drilling Operations 6

4.2 Formation Pressures and Drilling Fluids 10

5.0 Particulars of Well Position and Directional Path 12

6.0 Programme of Works 14

7.0 Activities Involving the Risk of Release of Fluids 15

8.0 Particulars of Geological Strata, Surveying and Well Design 17 8.1 Geological Formations and Fluids 17

8.2 Wellbore Direction Surveying 17

8.3 Relevant Particulars of the Well Design 21

9.0 Existing Well Details 24

10.0 Plug & Abandonment and Suspension 24

11.0 Attachments 25 11.1 Attachment 1: Rig Specifications, Synergy-1 26

11.2 Attachment 2: Well Control Stack-up Drawings 29

11.3 Attachment 3: Wellhead Configurations 31

11.4 Attachment 4: Casing Design Summary 34

Figures

Figure 1: PNR-1 / 1Z Location ...................................................................................... 3

Figure 2: Generic site layout with rig ............................................................................ 5

Figure 3: Well Profile, PNR-1 & 1Z ............................................................................ 12

Figure 4: Design Pore & Frac Pressure Gradients vs Depth ........................................ 16

Figure 5: Geological Prognosis, PNR-1....................................................................... 19

Figure 6: Geological Prognosis, PNR-1Z .................................................................... 20

Tables

Table 1: Diverter and BOP Plan .................................................................................... 6

Table 2: Wellhead Stack-up Planned for PNR-1 / 1Z .................................................... 8

Table 3: Pressure Testing Programme ........................................................................... 9

Table 4: Kick Tolerance Calculation Summary........................................................... 10

Table 5: Planned Drilling Fluids and Expected Formation Pressures ......................... 11

Table 6: Nominal Directional Profile for Preston New Road Pilot Hole (PNR-1) ...... 13

Table 7: Nominal Directional Profile for Preston New Road Sidetrack (PNR-1Z) .... 13

Table 8: Planned Well Operations ............................................................................... 14

Table 9: Geological Prognosis ..................................................................................... 18

Table 10: Surveying Programme, PNR-1 / 1Z ............................................................. 18

Table 11: Casing Plan, PNR-1 / 1Z ............................................................................. 21

Table 12: Minimum & Calculated Casing Design Factors .......................................... 22

Table 13: Cement Barrier Programme, PNR-1 / 1Z .................................................... 23


Notification of Intent to Drill Preston New Road 1 & 1Z on LJ/06

Particulars Required for Notification under Regulation 6(1) of BSOR

Page 2 of 37 Document No. PNR-DRI-NOT-001 12-Apr-2017

1.0 Name and Address of the Operator


6 Septre Court,

Bamber Bridge,

Preston PR5 6AW.

Contact: Mike Schneider – Drilling Manager

2.0 Particulars of the Type of Well

The well is referred to as Preston New Road 1 and 1Z (PNR-1 / 1Z) throughout this

notification. The Well Registration Number will be confirmed by the Oil and Gas

Authority but a well number of LJ/06-08 is anticipated. The well’s surface location will

be on EXL269 and the lateral extension will go into and produce from PEDL165. The

well is classed as exploration (unconventional reservoir).

Please note that PNR-1 is one of two wells being drilled at the Preston New Road site.

The particulars for Notification for PNR-2 (LJ/06-07 expected) will be provided under

separate cover. Conductor-setting particulars for Notification for both wells were

provided earlier under separate cover. It is planned to batch-drill top hole sections

below the conductors for the two wells, such that these operations will commence with

PNR-2, then the rig will skid over to PNR-1 and it will be drilled to total depth and

completed with production casing. After that the rig will skid back to PNR-2 and

complete that well to final depth.

PNR-1 is being drilled as an S-shaped pilot hole to the Hodder formation. The

geological information acquired will be used to select the landing depth for a horizontal

lateral, which will be drilled as a J-shaped sidetrack from the pilot hole as PNR-1Z. The

information gained from the pilot hole will also be used for selecting the landing depth

of the second J-shaped well, PNR-2. Within this Notification prognosed kick-off and

landing depths have been indicated for PNR-1Z based on seismic interpretation, and

are subject to change following evaluation of the pilot hole.

This Notification covers planned works up to and including installation of the

frac/production casing string. Following drilling rig release, the well will be stimulated

by hydraulic fracturing and then production-tested, and all works associated with that

will be the subject of a separate Notification to follow.

The site address is Preston New Road Wellsite, adjacent to PR4 3PJ, Lancashire

(nearest property).





Figure 1: PNR-1 / 1Z Location





3.0 Particulars of the Rig and Plant

The drilling rig to be used is DrillTec GUT’s rig “Synergy 1”. The rig uses a

hydraulically powered rack-and-pinion joisting system with a nominal capacity rating

of 3700kN. A summary of the rig’s specification is included as Attachment 1.

The rig is currently operating for NAM in the Berkel Field abandonment in Rotterdam,

and will be brought over to the UK specifically for this project.

Additional plant required during the programme will include:

• Cementing equipment: high-pressure pump unit(s), bulk cement storage, batch-

mix;

• Wireline logging unit;

• Lifting equipment: cranes and forklifts to the capacities required per

application;

• Drilled cuttings auger and skip loading bays.

A general site layout drawing is included in Figure 2 below, showing the drilling rig

and the noise wall (represented by 12m x 2.4m containers which won’t necessarily be

the case). The additional plant is not shown in the layout and will be spotted to suit the

operations.

At the time of this submission, no public announcement or press release has been made

by Cuadrilla Bowland Ltd concerning the engagement of DrillTec GUT for this work.





Figure 2: Preston New Road site layout with drilling rig

(Noise wall represented by 12m x 2.4m rectangles)





4.0 Particulars of Surface Equipment and Fluids to Control Well Pressure

4.1 Surface Equipment: Well Control During Drilling Operations

The diverter and blow-out preventer plan during drilling is shown in Table 1 below.

Since the top hole sections (26" and 16") will be batch-drilled starting with PNR-2,

diverters will be used on that well. Mud logging services (gas and flow detection plus

lithological analysis) will be in place for both wells from start to finish. No shallow gas

or artesian flow is anticipated in the first two hole sections, and if this is confirmed on

PNR-2 then no diverters will be used for top hole sections on PNR-1.

Table 1: Diverter and BOP Plan

PNR Well

in Sequence

26" to ~260m 16" to ~1318m 12-1/4", 8-1/2" & 6"

1st Well:

PNR-2

29-1/2" diverter

(alternatively

pilot hole with

21-1/4"

Diverter

21-1/4" annular

preventer used

as diverter

• 13-5/8" 5000psi annular

preventer

• 13-5/8" 10000psi double

pipe ram (upper VBR,

lower shear/blind)

• drilling cross

• 13-5/8" 10000psi pipe ram

2nd Well:

PNR-1

No diverter as long as mud logging

on 1st well confirms no gas (each

section)

Same as for PNR-2

Stack-up drawings for the 3 systems in Table 1 are shown in Attachment 2.

The wellhead is a “drill-through” style system manufactured to API6A by GE Oil &

Gas Limited, with components as listed in Table 2. Casing hangers are as follows:

• The 13-3/8" casing hanger is a wrap-around slip and seal assembly, with the 13-

3/8" casing is set above the levels at which any hydrocarbons are expected and

which will be confirmed by mud logging.

• The 9-5/8" casing hanger is a mandrel-type, run as part of the casing string with

the primary seal (pack-off) run through the BOP immediately after cementing.

A contingency wrap-around slip and seal assembly is available in case it is not

possible to land the mandrel hanger due to space-out (e.g. casing stuck off

depth).

• For the 5-1/2" casing hanger the primary option is a mandrel-type hanger with

a control line penetration. A contingency slip and seal assembly is also available

for this string but without control line penetration.





No H2S was reported from offset Bowland / Hodder wells in the area, however as a

precaution the upper housing of the 13-5/8" wellhead has been specified to DD-NL for

drilling the 8-1/2" pilot hole and subsequent sidetrack to horizontal, and the tubing

spool has been specified to EE-1.5.

The BOP and wellhead system will be function tested and pressure tested as shown in

Table 3. This also shows the plan for formation integrity and leak-off tests. The pressure

testing levels were selected as follows:

• 20" casing and 21-1/4" annular preventer are tested to 500psi based on the

shallow depth of the top of the Sherwood Sandstone, the continuity of the

porous sand through the 16" interval, the local absence of hydrocarbons in the

section, and the use of the annular preventer as a diverter.

• 13-3/8" casing / SH2 lower housing test to 4000psi based on being above a

theoretical gas-to-surface design from the 12-1/4" total depth and below 75% of

API rated burst strength for 72 lb/ft L80 casing of this size.

• 9-5/8" casing is tested to 5500psi based on being above the equivalent gas

column to surface exceeding a 1.0psi/ft formation break-down strength below

the casing shoe and below 75% of API rated burst strength for 53.5lb/ft L80

casing of this size.

• The 7" liner is tested to 5000psi based on being above a theoretical gas-to-

surface design from the 6" lateral and below 75% of API rated burst strength

for 29 lb/ft L80 casing of this size.

• The 5-1/2" x 4-1/2" frac string / tubing head (wellhead section C) is tested prior

to stimulation to 9500psi, being the maximum treatment pressure planned for

initiating injectivity.

Wellhead schematics are included in the Attachments:

• Wellhead to the end of drilling, shown with 5-1/2" contingency wrap-around

casing hanger without control line penetration though the mandrel hanger with

control line penetration sits in the same spool location, directly replacing it;

• Wellhead with 5-1/8" frac tree installed - please note, frac tree installation and

stimulation operations will be the subject of a separate, later Notification;

• Wellhead with 2-9/16" production tree installed, showing integral tubing bonnet

within mono-block valve tree - similarly to form part of a later Notification.

The latter two stack-ups are included at this stage for general information purposes

only.

Results of kick tolerance calculations for PNR-1 (pilot hole) are included in Table 4.

The sidetrack will be shallower, and as such the pilot hole presents the more extreme

case.





Table 2: Wellhead Stack-up Planned for PNR-1 / 1Z

Wellhead Stack-up Per Section A-B-C API Specification

C Tubing Head:

• 11" 10,000psi x 5-1/8" 10,000psi head

with tie-downs

• Secondary seal assembly for 5-1/2"

casing stub; metal/metal.

• 2 x 2-1/16" 10,000psi studded side outlets

with valves and accessories

• Tubing head adapter, 5-1/8" 10,000psi as

part of production tree.

PU-EE1.5-PSL3-PR2

B Drill-through wellhead assembly (high pressure

wellhead):

• 21-1/4" 2,000psi bottom x 13-5/8"

10,000psi top

• Intermediate flange 13-5/8" 5,000

• 4 x 2-1/16" studded side outlets (2 per

annulus), machined to accept Valve

Replacement Plug, supplied with 1 x

VRP

• each side outlet with 1 x 2-1/16" 5,000 /

10,000psi gate valves (pressure rating as

per flange above)

• Casing hanger for 9-5/8": mandrel-type

with pack-off bushing.

• Contingency slip-type hanger in the event

of stuck 9-5/8"casing / off depth.

• Casing hanger for 5-1/2": mandrel hanger

with control line penetration; back-up of

automatic slip & seal without

penetration.

Temperature: U

Material: AA/DDNL

(lower housing AA, upper

DDNL)

PSL 2

PR2

9-5/8" mandrel hanger:

P/U-DDNL-PSL2-PR2

5-1/2" mandrel hanger:

special design by GE in

8630 steel

5-1/2" slip & seal hanger:

U-DD-2-2

A Casing head assembly (low pressure wellhead):

• 20" OD slip-type x 21-1/4" 2,000 psi

flange

• 2 x 2" 2,000 psi line pipe side outlets or

2-1/16" R-27 flanged

• One side outlet with 2-1/16" gate valve,

other side with bored bull-plug, needle

valve and pressure gauge

• Casing hanger for 13-3/8": automatic slip

& seal.

Temperature: P/U

Material class: AA

Product Spec. Level 1

Performance Req. 2

Casing hanger: L-AA-

PSL3-PR2





Table 3: Pressure Testing Programme

Hole/

Casing

Size

Test

Item Comments Pressure

psi

Time

26"

hole

Diverter

on 28"

Function test of diverter element and

valve

n/a

20"

casing

Casing

head +

diverter

Slip-lock housing O-ring + diverter

element and valve + casing against

cemented shoe track

500 10 min

Top of

16"

Shoe test Hydraulic test at cemented shoe to

15 lb/gal EMW

Approx.

220psi

13-3/8"

casing

13-5/8"

BOP +

SH2

spools

1. 13-5/8" pack-off via test port

2. SH2 spools prior to 9-5/8" casing

3. BOP prior to 9-5/8" casing

500 / 4000

500 / 4000

500 / 4000

10 min

10 min

10 min

Casing +

blind rams

Before drilling out shoe track. 500 / 4000 10 min

Top of

12-1/4"

FIT / LOT Up to 15.5 lb/gal EMW for kick

tolerance

N/A

9-5/8" 13-5/8"

BOP Test

+ upper

SH2 spool

1. Upper SH2 housing after 9-5/8"

pack-off set; + full stack test with

test plug

2. Between pack-off seals / BX160

gasket

500 / 6000

(4000

annular)

500 / 4000

10 min

10 min

Casing

Test

After bumping plug or before

drilling out all cement in shoe track

5500 10 min

Top of

8-1/2"

LOT Conducted below 9-5/8" shoe (kick

tolerance based on 16.5ppg)

(X)LOT

7"

Liner test After bumping plug or before

drilling out all cement in shoe track

500 / 5000

10 min

Every

max. 21

days

13-5/8"

BOP

Full stack test as per test after 9-5/8"

casing

500 / 6000

(4000

annular)

10 min

Top of

6"

LOT LOT for hydraulics management in

6" hole. XLOT may be performed if

required for geotechnical reasons.

(X)LOT N/A

4.5" x

5.5"

Casing /

Tie-back

1. On bumping plug:

2. Prior to stimulation; including

tubing spool/secondary seal

2500

9500

10 min

10 min





All tests will be recorded on charts and annotated with well name, date, item being

pressure tested, and Supervisor’s name. Mud loggers will digitally record well

construction pressure tests as well.

Table 4: Kick Tolerance Calculation Summary

Hole Size 12-1/4" 8-1/2"

Target kick margin 25bbl 25bbl

Kick scenario 0.5ppg above mud weight 0.5ppg above mud weight

Mud weight in use 12ppg (for borehole

stability – higher than

expected pressure)

13.5ppg (Actual may be

higher for borehole

stability)

LOT / FIT at previous

shoe

15.5ppg 16.5ppg

Pressure safety margin 441psi 295psi

Wellbore vertical depth 1845m TVD 3420m TVD

In the event of a lower formation strength being measured at the shoe, the kick tolerance

will be reassessed, which may mean that either the section TD is reduced or, for the pilot

hole, a 7" drilling liner could be required at a calculated point. A risk assessment for this

will be included in the executable programme. It is noteworthy that the prognosed

maximum formation pressure gradient for the Bowland Shale is based on mathematical

derivations from the hydraulic fracture treatments done on Preese Hall-1, though the

calculated formation pressures are higher than the mud weight actually used for drilling

and no well flow was ever in evidence.

4.2 Formation Pressures and Drilling Fluids

A summary of the drilling fluids and expected formation pressure gradients is given in

Table 5 below.

The planned casing programme is given in Section 8.3. All hole section and casing

setting depths are subject to significant adjustment depending on geological and drilling

conditions.

A geomechanical study is currently being completed by Petrolern which is designed

to guide mud weight selection for both borehole stability (avoidance of break-outs)

and avoidance of exceeding fracture gradients (control of dynamic mud losses), and

also provide an additional derivation of predicted pore pressures. The study will be

used to advise the executable drilling programme.





Table 5: Planned Drilling Fluids and Expected Formation Pressures

*See note above regarding derivation of pore pressure estimate from Preese Hall-1

frac data.

Nominal

Hole Size

(inches)

Formations and

Drilling Fluid (Mud)

Expected

Formation

Fluid

Pore Pres.

Gradient

lb/gal

Fluid

Density

lb/gal

26"

Middle Sands / Mercia

MDST: salt-saturated polymer

mud in case of halite beds.

Fresh water,

possibly

brine

8.3 10.2

16"

Sherwood Sandstone: same

salt-saturated polymer mud

with close attention to

possible mud losses.

Water

(brine) 8.75 10.2

12-1/4"

Manchester Marl/Millstone

Grit Group: LTOBM for

borehole stability and quality.

Gas

possible

9.8

(possible)

10.0 – 12.0

for borehole

stability

8-1/2"

Bowland Shale, Hodder MST:

LTOBM carried over from

previous section.

Gas

Expected

9.8 – 13.3*

(possible)

11.0 – 14.0

for borehole

stability

8-1/2"

sidetrack &

6" lateral

Bowland Shale, Hodder MST:

LTOBM carried over from

previous section.

Gas

Expected 9.8 – 13.3*

11.0 – 14.0

for borehole

stability

Production

Casing

Completion fluid: fresh water

+ corrosion inhibitor and

oxygen scavenger

Gas present

only after

perforating

Cased 8.75 – 9.8





5.0 Particulars of Well Position and Directional Path

a) The Ordnance Survey National Grid reference of the location of the top and

bottom of the well is:

Ground level Elevation (GLE): 12.5m

Rotary Table Elevation (RTE): 8.25

Surface location:

Well (OSGB 36 (2)) Northing/m Easting/m

PNR-1 432749.5 337433.6

PNR-2 (for reference) 432752.2 337437.8

Bottomhole location:

Well (OSGB 36 (2)) Northing/m Easting/m TVDRT/m

PNR-1 432749.5 336884.3

PNR-1Z 432749.5 335637.2 2200

b) The well is planned to be drilled directionally in an S-shape as PNR-1, per Table

6. It will then be sidetracked as a J well as PNR-1Z per Table 7. The profile of

the well is shown in Figure 3 below.

Figure 3: Well Profile, PNR-1 & 1Z





Table 6 and Table 7 below indicate the most likely depth cases for PNR-1 & 1Z, based

on placing a horizontal in the lower part of the Upper Bowland. This will be subject to

core analysis in the pilot well to evaluate the most prospective target. The total depths

of each hole and the landing points are all subject to change based on both geological

and operational results.

Table 6: Nominal Directional Profile for Preston New Road Pilot Hole (PNR-1)

Table 7: Nominal Directional Profile for Preston New Road Sidetrack (PNR-1Z)





6.0 Programme of Works

Expected earliest commencement date is early July 2017, subject to site and

conductor installation completion. Depths are measured depths from rotary table (RT)

unless otherwise indicated.

Table 8: Planned Well Operations

Operation Days

Rig mobilization: skid rig over from PNR-2 (from top-hole drilling on

adjacent well). 1.0

Spud well and drill 26" hole to 260 meters. 1.5

Run and cement 20" casing & install and test wellhead. 1.0

Drill 16" hole to circa 1318m and log. 4.2

Run and cement 13-3/8" casing. Install casing head, 13-5/8" BOP and

pressure test. 2.0

Make up BHA and drill out shoe track. Perform FIT. 0.5

Drill 12-1/4" hole to 1908m (adjusted according to actual lithology). 3.4

Run wireline logs. 1.5

Run and cement 9-5/8" casing. Set and test wellhead packoff. 2.5

Drill out shoe track and test formation leak-off strength. 1.0

Drill 8-1/2" hole to approx. 3500m, with coring. 27.9

Run electric wireline logs to evaluate the 8-1/2" section. 3.0

Abandon lower section of PNR-1 and set kick-off plug for sidetracking

at selected depth. 2.5

Sidetrack to PNR-1Z in 8-1/2" hole, building to (near) horizontal at

nominal TD of 2440m. 8.2

Run + cement/test 7" liner. 2.0

Make up BHA and drill shoe track. Conduct LOT. Drill 6" lateral to

nominally 3460m. 8.2

Run electric logs on drill pipe (contingency of wireline / tractor). 4.0

Run 5-1/2" x 4-1/2" frac string and cement (contingency of 4-1/2" liner). 2.0

Clean out frac / production string (incl. contingency of tie-back). 2.0

Total including rig mob/demob: 78.4





7.0 Activities Involving the Risk of Release of Fluids

The design pore and fracture gradients versus formations are summarised in Figure 4.

1. Mercia Mudstone: no abnormal pressures have been found with the exception of

shallow artesian water flow at 19m in Preese Hall-1, which will be mitigated with

the shallow conductor in this well. The water monitoring boreholes drilled during

July-2016 have now provided detailed lithological information, and also

established the limited potential for artesian water flow. The executable conductor

programme has included these details. Below potential artesian conditions, the

Mercia Mudstone can be drilled with 8.9 lb/gal to the target depth of circa 260m.

Based on all available offset well information, the Mercia Mudstone has not been

found to contain shallow gas. The salt-saturated mud system is planned due to the

potential for halite inclusions above the Sherwood Sandstone, and not for

hydrostatic pressure.

2. Sherwood & St. Bees Sandstone: Similar to the Mercia Mudstone, no abnormal

pressures or elevated gas levels have been noted in any offset wells. The Sherwood

Sandstone is prone to mud losses, particularly in the St. Bees formation, and this

will be monitored closely while the salt-saturated mud system is in use.

3. Collyhurst Sandstone and Millstone Grit Group (MGG) below Manchester Marl:

The marl forms a regional seal and first hydrocarbons are generally encountered

only beneath the Manchester Marl, in the Collyhurst Sandstone or Millstone Grit.

From the nearby Elswick Gas Field the original reservoir pressure is taken as

1,726psia at 3395ft TVDRT, giving a gradient of 9.8lb/gal equivalent mud weight

(EMW). This overpressure was not seen in Preese Hall-1 where a mud weight of

9.3lb/gal was adequate, but precautions for an EMW up to and in excess of that

seen in Elswick will be provided for. In any event, borehole stability has been an

issue in the past (Grange Hill, borehole collapse) and elevated mud weights may

be required for borehole support.

4. Bowland Shale Group: no direct formation pressure measurement has been

possible due to the very tight nature of the predominantly shale formation, but the

pore pressure has been deduced from Preese Hall-1 fracturing treatment data at

each of the perforated zones. The average value calculated is 0.69psi/ft (13.3lb/gal

EMW) in the Lower Bowland. The section was drilled with a mud weight of only

10.1lb/gal so evidently the formation is extremely tight as no well flow resulted

even during prolonged coring and logging. Nonetheless there is the potential for

locally isolated lenses of higher permeability which could be charged to such a

high pore pressure, so 0.69psi/ft is taken as the design pore pressure. For the

planned total depth of the pilot hole this in turn requires a 10,000psi BOP.

5. Hodder Mudstone: this was only penetrated in Becconsall-1Z and due to the tight

nature of the formation, again no direct pressure measurement was possible. Being

a mudstone, gas levels were low while drilling with a mud weight designed to

provide borehole stabilisation rather than gas control. There are no indications from





mud logging and cuttings that pore pressures are higher than in the Bowland Group

and so the same maximum value of 0.69psi/ft is used for the section to total depth.

6. Kick tolerance: See Section 4.1 above.

7. The implementation of the defined drilling practices in association with the

specified well control equipment and drilling fluid systems will minimise any

chance of accidental release of fluids from the well during its construction. Sensors

for gas levels, pit volume and system pressures will be installed, tested and

monitored throughout this operation, with alarms set at suitable levels by the mud

logging service contractor. Flow checks for a minimum 10min will be made prior

to each trip out of the hole from the 16" borehole onwards. Regular well control

drills and site safety meetings will be held and recorded in the rig’s IADC logbook.

Figure 4: Design Pore & Frac Pressure Gradients vs Depth





8.0 Particulars of Geological Strata, Surveying and Well Design

8.1 Geological Formations and Fluids

The PNR-1 prospect is located 3.7km south of Preese Hall-1 and 9.5km north-west of

Hesketh-1. It lies within the Thistleton Fairway which forms part of the Carboniferous

basin known as the Bowland Basin. The fairway surrounding PNR-1 is bound by

Variscan reverse faulting, comprising of the Haves-Ho Fault to the West and Anna’s

Road / Moor Hey Faults to the East. The well is positioned in a relatively flat lying part

of the fairway, making it an ideal location for future laterals.

The Bowland Basin in which the Thistleton fairway resides is bound to the north by the

Bowland High, and to the south by the Rossendale High (Fraser and Gawthorpe, 1990).

It is an intracratonic extensional basin formed during Late Devonian early

Carboniferous times in relation to the intensified N-S crustal extension. The basin was

subsequently inverted during the Variscan Orogeny, leading to the inversion of many

of the existing faults. The Carboniferous basin fill comprises marine claystones/shales

interbedded with sandstone, siltstones and limestones.

The primary target reservoir is the Bowland Shale Formation, with the Hodder

Mudstone being a secondary target and the shales within the Millstone Grit Group,

namely the Sabden Shales being a tertiary target.

The geological prognosis is listed in Table 9, and shown together with the seismic

sections in Figure 5 (PNR-1) and Figure 6 (PNR-1Z). The seismic interpretation

identifies the potential for a major reverse fault within the MGG, which may result in

drilling directly into a repeat section of Lower Bowland Shale, and then back into either

the MGG or Upper Bowland Shale. The geological prognosis also identifies a minor

reverse fault at 1890m-MD leading to a repeat section.

8.2 Wellbore Direction Surveying

The directional surveying programme is shown in Table 10. The PNR-2 wellbore, being

drilled at 5m surface separation from within the same cellar, is the only wellbore that

will initially present a collision risk. In addition to the surveying shown in Table 10, a

gyroscope (non-magnetic) survey of the final well may be taken to aid any future infill

well planning.





Table 9: Geological Prognosis

Table 10: Surveying Programme, PNR-1 / 1Z

26" hole Rotary BHA: MWD surveys

16" hole Directional BHA: MWD surveys

12-1/4" hole Directional BHA: MWD surveys

8-1/2" hole and sidetrack Directional BHA: MWD surveys

6" hole Directional BHA: MWD surveys

RT fm GL 8.25

GL fm MSL 12.5

RT fm MSL: 20.75

Formation Top / Event m-TVDSS m-TVDRT m-MDRT

Superficial (Boulder Clay 10 11 10

Mercia Mudstone -20 41 40

Shallow (28") Conductor -40 60 60

Deep (20") Conductor -240 260 260

Sherwood Sandstone -270 290 290

Sherwood St Bees Sst -580 600 610

Manchester Marl -1150 1170 1200

Anhydrite 1 -1180 1200 1240

Anydrite 1 Base -1200 1220 1260

Anhydrite 2 -1230 1250 1290

Anhydrite 2 Base -1240 1260 1300

13-3/8" Surface Casing -1260 1280 1320

Collyhurst Sandstone -1310 1330 1370

Variscan -1350 1371 1420

Upper Bowland Shale -1650 1670 1730

Minor Fault -1800 1820 1890

9-5/8" Intermediate Casing -1820 1840 1910

Core interval 1: Upper Bowland -2050 2068 2150

Lower Bowland -2220 2241 2320

Core interval 2: Lower Bowland -2220 2242 2330

Hodder (Upper) -2680 2701 2780

Core interval 3: Hodder -2680 2703 2790

TD, PNR-1 -3420 3431 3500

Kick-off Point to PNR-1Z -1942 1963 2036

Drilling Liner -2180 2200 2440

Production Casing / TD -2180 2200 3460





Figure 5: Geological Prognosis, PNR-1





Figure 6: Geological Prognosis, PNR-1Z





8.3 Relevant Particulars of the Well Design

The casing programme is summarised in Table 11 below. The cementing programme

and verification scheme is shown in Table 13. The casing specifications are generally

higher than required due to stock availability.

Table 11: Casing Plan, PNR-1 / 1Z

Hole

Size "

Casing

OD "

Casing Setting Criteria and

Purpose

Grade

Lb/ft

Thread

Setting Depth,

MD/m RT

PNR-1&1Z

32 28 Shallow conductor(s): set ahead

of main drilling; see separate

Notification.

X52

WT 0.5-0.6"

Up to 50

26 20 Deep conductor: set in Mercia

Mudstone to nominally 30-50m

above Sherwood Sandstone.

Covers claystones and halites

while drilling next section.

94 lb/ft K55

sufficient but 133

lb/ft in stock;

BTC

260

16 13-3/8 Surface casing: set nominally

100m below top Manchester Marl

(after anhydrite bands) to provide

impermeable seal between the

Sherwood (aquifer) and

hydrocarbon zones.

L80-1

72 lb/ft

Vam Top

1318

(18° Incl.)

12-1/4 9-5/8 Intermediate casing: across

Millstone Grit Group to below the

prognosed fault in the Upper

Bowland Shale: part of barrier

envelope for possibly gas-bearing

sands (note 2).

L80-1

53.5 lb/ft

Vam Top

1908

(18° incl.)

8-1/2 7 Cemented liner across the build

section to up to 90° inclination.

L80-1 29 lb/ft

Vam Top HT

2440

(90°incl.)

6 4-1/2 x

5-1/2

Planned as tapered 5-1/2" x 4-1/2"

string cemented at least 300m into

7" liner (option of cemented 4-

1/2" liner + uncemented tapered

tie-back string is retained).

5-1/2" P110

20lb/ft x 4-1/2"

13.5 lbs/ft

Vam Top HT

3460

(90 - 94° incl.)

Notes:

Casing API grades and lb/ft have been selected based on conventional casing design

calculations using the minimum casing design factors in Table 12, which are in

accordance with Cuadrilla’s Well Integrity and Operational Controls manual. The

casing design calculations were performed using TechDrill’s “DSP-One” casing design





module with summary graphs (13-3/8" casing onwards) included in Attachment 4. The

graphs display in terms of “normalised safety factors” which show the lowest value of

safety factor calculated, normalised by the minimum design factor in Table 12.

Therefore any value above 1 complies with the design criteria.

�� =��

��

Table 12: Minimum & Calculated Casing Design Factors

Casing Load Design

Factor

Internal yield (burst) 1.1

Collapse 1.1

Tension (stuck casing,

cementing, pressure

testing)

1.25

Tri-axial stress 1.25





Table 13: Cement Barrier Programme, PNR-1 / 1Z

Casing (or Liner) Type and Depth (m)

Proposed Low Permeability Strata - Set Into

Cement Details Purpose of Casing/ Liner and Cement Barrier Verification

Shallow conductors

Top of Mercia Mudstone

Pre-installed: separate Notification

Structural support and site protection

Deep Conductor

20" casing

26" hole

250 – 270m

Mercia Mudstone Group

Light-weight lead cement slurry with standard density tail cement (min. 100m tail).

Protect shallow groundwater from well fluids during drilling. Provide a permanent seal across the Mercia Mudstone.

Verified by cement returns + pressures during cementing – top up if required. Hydraulic test (FIT) on drilling out shoe - cement shoe squeeze if required.

Surface Casing

13-3/8" casing 16" hole

1,318m

Manchester Marls Formation

Light-weight lead cement slurry with standard density tail cement (min. tail fill to Sherwood base); specifications tailored to cementing across Sherwood SST.

Protect the Sherwood Sandstone from well fluids during deeper drilling. Prevent fluids migration into Sherwood Sandstone from underlying units (for example the Collyhurst Sandstone).

Verified by cement returns + pressures during cementing. Hydraulic test (FIT) on drilling out shoe - cement shoe squeeze if required. CBL/VDL for monitoring purposes only.

Intermediate Casing

9-5/8"casing / 12.25" hole

1,908m

Upper Bowland Shale

Gas blocking cement from shoe of 9-5/8" casing at least up to base of the Sherwood Sst within 13-3/8" annulus. External casing packer installed close to 13-3/8" shoe.

Casing across Collyhurst Sandstone and Millstone Grit for well control purposes. Provides additional barrier between Sherwood SST and well fluids.

Verified by cement returns + pressures during cementing. Hydraulic test (FIT, LOT or XLOT) on drilling out shoe - cement shoe squeeze if required. CBL/VDL for verification purposes.

Drilling Liner

7" / 8.5" hole

2,440m

Target Formation

Gas blocking cement along liner length.

Part of primary barrier preventing uncontrolled release of well fluids to adjacent formations.

Verified as per 9-5/8" casing.

Production/frac string: 4-1/2" casing / 6" hole

3,460m

Target Formation

High resilience / high flexural strength cement designed to withstand the hydraulic fracturing pressure and perforations cycles.

Provides isolation within the lateral section to be hydraulically fractured.

Verified by cement returns + pressures during cementing. CBL/VDL for verification purposes in first well.





9.0 Existing Well Details

In the case of an existing well: (a) a diagram of the well, (b) a brief history of the well

including a summary of previous operations, (c) its present status and condition.

The pre-existing well construction will be the cellar and the pre-set 28" conductor set

at least 10m into firm Mercia Mudstone, per separate Notification. The cellar will be

constructed 10m long x 2.9m wide x 4.5m deep to accommodate both PNR-1/1Z and

PNR-2. The cellar depth will provide for the wellhead plus production tree to be housed

below site surface level.

10.0 Plug & Abandonment and Suspension

The lower section of PNR-1 is to be abandoned per guidelines published by Oil & Gas

U.K., with cement plugs being set between all distinct permeable zones within the

openhole, which may involve overlapping of zones that are too close together to plug

separately. It is anticipated that this would only involve a cement plug between the

Bowland Shale and the Millstone Grit Group above. The kick-off plug may be below

this depth and so the abandonment of the lower section would be achieved with the

kick-off plug (subject to confirmation of the sidetracking depth).

Suspension after running the frac (5-1/2" x 4-1/2") string: following cementation, the

string will be displaced to a potentially underbalancing fluid and therefore an inflow

test will be conducted. This will verify the casing string as a deep-set barrier. Following

confirmation of pressure integrity, the 5-1/8" frac tree valves will be installed as a

shallow barrier while the well awaits further operations.

The casing programme for this well has been specifically designed to facilitate eventual

abandonment, providing for separation of separate geological intervals which could

potentially result in flow if not isolated.





11.0 Attachments

1. Summary of Rig Specifications

2. Well Control Stack-up Drawings:

• 21-1/4" diverter (similar arrangement for 29-1/2")

• 13-5/8" BOP

3. Wellhead Configurations

• Wellhead during drilling

• Wellhead with 5-1/8" 10,000psi frac tree

• Wellhead with 2-7/8" mono-block production tree

4. Casing Design Summary





11.1 Attachment 1: Rig Specifications, Synergy-1

Ref. Description CONTRACTOR's Supplied Equipment

A LAND RIG SUMMARY

GENERAL DESCRIPTION

- Name MAX STREICHER VDD 370.1 Synergy 1

- Classification Self supporting land rig

- Year Built/Refurbished Construction year 2004

- Nominal drilling depth 5.000 m with 3-1/2" drillpipe

MAST

- Type Gear rack

- API Gross Nominal Capacity 3.700 kN

DRAWWORKS

- Type MAX STREICHER Rack & Pinion Hoisting System

- Drive Hydraulic motor

- Power Rating 900 kW

- Max. designed hoisting capacity 3,700 kN pull, 60kN push

AUXILIARY BRAKE Main 6 hydraulic motion control valves (Rexroth) + auxiliary 6

multi-disc brakes (Zollern)

SUBSTRUCTURE

- Height 8.25m

- Clear height below rotary beams 7.77m

- Setback load N/A (No setback capability)

- Rotary capacity 3,700 kN

- Max. Combined load 3,700 kN static

ROTARY TABLE (auxiliary drive only)

- Drive MAX STREICHER

- Size (inch) 37-1/2 “

- Power Rating (HP) 60 - 180 kW Hydraulic motor; 40 kNm @ 15 rpm

TOP DRIVE SYSTEM

- Make, type MAX STREICHER Hydraulic

- Rated capacity 350 bar, 3.700 kN, 465 kW

- Rated torque M/U, B/U torque 85 kNm

continuous 67 kNm@70 rpm and 19 kNm @ 190 rpm





- Maximum rotary speed 190 rpm

RIG POWER

- Number of Engines 4

- Number of Generators 4

- Generator power 4 x 1065 kVA / output max. 4 x 800 kW, cont. 4 x 600 kW

- SCR system VFD – Schneider Electric, Siemens

MUD PUMPS

- Make, type Wirth TPK 1600 12”

- Number of pumps 2

- Power Rating 1600 HP each

MUD SYSTEM

- Active tank capacity 118 m³

MUD TREATMENT

- Shale shakers Shaker screens optional at extra cost

- Make, type 3 x Derrick, FLC 2000 4 Panel

-Gumbo (hydrated clays) removal 1 pc

- Make, type Derrick Flo-Line Primer

- Desander Not supplied

- Make, type "

- Desilter yes

- Make, type Derrick 16x4”

DRILL STRING

- Drill Pipe

- Size 5” 3-1/2”

- Length 3500 m 3950

- Weight 19,5 lbs/ft 15,5 lbs/ft

- Grade S-135 S-135

- Heavy-Weight Drill Pipe

- Size 5” 3-1/2”

- Quantity 9 joints 36 joints

- Drill Collars

- Size 4-3/4” 6-3/4” 8-1/4” 9-1/2”

- Quantity 9 12 at request at request





BLOWOUT PREVENTERS

- Annular preventers

- Make Xinde

- Size 13 5/8”

- Pressure rating 5000 psi

- Ram type preventers

- Make Xinde

- Size 13 5/8”

- Pressure rating 10.000 psi

Single / Double Double & Single (with shear/blind)





11.2 Attachment 2: Well Control Stack-up Drawings

A. Diverter Arrangement

Bell Nipple

Diverter Spool

21 1/4" flange installed onto 20" casing

20" casing, flange

installed and

cemented in place

Diverter

Annular

6" ID Diverter Line

21-1/4" 2000psi

Annular BOP

21-1/4", 2000psi

21-1/4", 2000psi





B. BOP

7000mm

6777mm

Annular

1260mm w/ Bell Nipple

1226mm w/o Bell Nipple

Total Height

1790 mm

Double ram

1470 mm

Choke Line Kill Line

Drilling Spool

910 mm

880 mm

Single ram

7490mm

Synergy 1 - BOP - Wellhead & 13 5/8"x 10K BOP Schematic

Rotary Beams

7770mm hoisting cross beam

Center Flowline

Lower Edge Flow Line

Substr

uctu

re

Substr

uctu

re

11” - 10000

2 7/8" - 5" Var. Rams

Shear Rams

13 5/8” - 10.000

Annular 13 5/8" 5k psi

13 5/8"-10.000psi

5" Pipe Rams

13 5/8"-10k

13 5/8"-10k psi

13 5/8" 10k psi

13 5/8" 10k psi

13 5/8"-10k

13 5/8"-5k psi

13 5/8"-5k psi

13 5/8"-5k

21-1/4" 2k psi





11.3 Attachment 3: Wellhead Configurations

Wellhead: End of Drilling Phase





Wellhead and Frac Tree





Wellhead and Production Tree





11.4 Attachment 4: Casing Design Summary

Normalised Safety Factors:

a) 13-3/8"





b) 9-5/8"





c) 7" Liner





d) 5-1/2" x 4-1/2" Tapered String

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