ENVIRONMENTAL METHOD STATEMENT FOR · PDF fileConsequently, this Environmental Method...

HSEC-BB-PD-01 Environmental Method Statement_Drilling

Rev 03 This is an uncontrolled copy when printed 1

CELTIQUE ENERGIE

BROADFORD BRIDGE – 1

PERMITTING DOCUMENTATION

ENVIRONMENTAL METHOD STATEMENT

FOR DRILLING

REVISION DATE PREPARED CHECKED APPROVED

01 01/11/2013 J Dobson P Bird



Document Number HSEC-BB-PD-01

Review Date March 2015



Table of Contents Table of Contents ............................................................................................. 2

1 Introduction ................................................................................................ 3

1.1 Background ........................................................................................................ 3

1.2 Referenced Documentation .............................................................................. 3

1.3 Document Structure .......................................................................................... 3

1.4 Permit Planning ................................................................................................. 4

2 Overview ..................................................................................................... 5

3 Site Design and Operation ......................................................................... 9

4 Well Integrity & Groundwater Protection ............................................... 13

4.1 Drilling & Groundwater Protection ................................................................. 13

4.2 Rig Demobilisation .......................................................................................... 17

4.3 Groundwater Risk Assessment & Monitoring ............................................... 17

4.4 Surface Water Risk Assessment & Monitoring......................................... 18

5 Pollution Prevention and Monitoring ...................................................... 20

5.1 Pollution Prevention ........................................................................................ 20

5.2 Environmental Baseline & Risk Assessment ........................................... 20

5.3 Surface Water Monitoring & Management ..................................................... 20

5.4 Noise Monitoring & Management .............................................................. 21

6 Environmental Management .................................................................... 23

6.1 HSE Monitoring & Reporting ........................................................................... 23

6.2 Emergency Preparedness & Response.......................................................... 24



1 Introduction 1.1 Background

This Environmental Method Statement has been produced to accompany the WR11 submission of the notice of intent by Celtique Energie Weald Limited (subsequently referred to as Celtique) to construct a boring for the purpose of searching for minerals as required under section 199 of the Water Resources Act 1991 (as amended by the Water Act 2003). This well is classified as a Non-inert Mining Waste Operation without a Mining Waste facility The exploratory drilling site at Broadford Bridge received planning permission from West Sussex County Council (WSCC) in 2013 – permit WSCC/052/12/WC. This method statement reflects the agreed conditions from the planning permission and the statutory consultee responses (which included both the Environment Agency and Natural England). Celtique is currently only applying for a Waste Management Permit to cover the drilling of the Broadford Bridge-1 borehole. In the event that potentially economic hydrocarbon reserves are identified, a separate permit application or a variation to this permit will be made to address the testing of this well. Consequently, this Method Statement only covers the drilling of the borehole. The Broadford Bridge-1 borehole is a conventional well and will not, at any stage, involve hydraulic fracturing.

1.2 Referenced Documentation

This Method Statement summarises and references:

The Environmental Statement (which contains supporting site studies and environmental risk assessments) was produced by Celtique and submitted as part of the planning process. The Environmental Agency (EA) as a statutory consultee has previously reviewed and commented on these studies;

Technical Documents which support the Permit submission including: o Summary of Celtique’s HSE Management System (HSEC Management Standards,

document number HSEC-MS-001); o Site Condition Report and Management and Monitoring Plan - including information

on environmental baseline data (document number HSEC-BB-PD-03); o HSEC Waste Management Plan (document number HSEC-BB-PD-04); o “Green lined” Site Plan (document number HSEC-BB-PD-05); o Non-technical summary (document number HSEC-BB-PD-02).

In addition it references those arrangements which will be put in place to manage normal and emergency operations at the Broadford Bridge-1 site including:

o Environmental Management Plan (as contained in the overarching HSEC Management Plan, document number HSEC-BB-OP-01);

o Pollution Incident Plan (as contained in the overarching Emergency Response Plan, document number HSEC-BB-OP-02);

o Management Systems Bridging Document (document number HSEC-BB-OP-03). These above referenced documents reflect and comply with the guidance contained in EA Pollution Prevention Guidelines:

PPG5: Works & maintenance in or near water;

PPG7: Safe operation of refuelling facilities;

PPG18: Managing firewater and major spillages;

PPG21: Incident Response Planning;

PPG22: Dealing with spills.

1.3 Document Structure

The document is structured as follows:

Section 2 provides an Overview of the proposed activity;



Section 3 describes the Site Design & Operation, providing information on arrangements for liquid containment and the storage of fuel, drilling fluids and drilling additives;

Section 4, Well Integrity & Groundwater Management, provides relevant information on the well (drilling operation, casing programme, mud management). It describes the controls in place to prevent pollution and summarises the results of the risk assessments carried out to demonstrate groundwater protection (HRA) and surface water protection (ERA);

Section 5, Pollution Prevention, reinforces the arrangements in place to prevent environmental impacts. It specifically addresses:

o Fugitive emissions to surface water and noise impacts; o The measures in place to establish a noise and surface water baseline; o Planned monitoring against this baseline (and references the response plans which

may be implemented in response to the findings of such monitoring).

Section 6, Environmental Management, describes the controls in place to mitigate environmental impact in both normal and emergency situations.

1.4 Permit Planning

It is Celtique’s intent to initially apply for a Mining Waste permit specifically to drill the Broadford Bridge -1 borehole. Consequently, this Environmental Method Statement covers the period from construction of the well site, through to the drilling rig moving on site to commence drilling the borehole through to the cessation of drilling and the securing of the well.

If the borehole indicates the presence of hydrocarbons, plans will be developed to test the well. As part of this well test planning process, Celtique will then additionally submit both:

An application for a variation of this Mining Waste Permit to cover testing;

An application for a Radioactive Substances Regulations (RSR) Environmental Permit to manage any Naturally Occurring Radioactive Materials (NORM) anticipated to be produced during the test.

and this Environmental Method Statement and other supporting documentation will be updated accordingly to address this testing operation and support these additional permit applications.



2 Overview The boring (hereafter referred to as the Broadford Bridge-1 well) in licence PEDL-234 involves the construction of a temporary well site within an enclosed compound to drill an exploratory well. Should no hydrocarbons be encountered all structures, buildings and enclosures will be removed and the site restored. Should hydrocarbons (oil or gas) be encountered, short term well testing may be undertaken to assess economic viability. This overview only covers the drilling of the borehole. It does not address testing of the well which will be the subject of separate permit applications. In summary, the work will involve:

Site clearance, involving the excavation and storage of the top and sub soils and the construction of temporary earth bunds on the northern and eastern boundaries of the well site compound to store excavated topsoil and subsoil;

Construction of the access track using crushed stone delivered by HGVs;

Creation of a staff car park within the compound but outside of the drilling area;

Construction of a concrete chamber sunk into the ground (the “cellar”) to include large diameter conductor pipe which will be pre-set either by drilling or using an augur rig to a depth of around 200ft.

Delivery of a drilling rig and ancillary drilling equipment for construction of an exploratory well (typically a 750 to 1000 HP rig). The drilling rig will be placed over the cellar, and the well will be drilled through the conductor pipe;

Purpose built tanks for the storage of drilling mud and rock cuttings. (It is noted that the mud tanks are provided by the drilling contractor and the cuttings tanks by the waste disposal contactor. Additional tanks for the storage of Oil Based Mud, if used, would be supplied by the mud contractor);

External lighting to the drilling rig illuminating the rig floor, mud tanks and pumps, catwalk, doghouse and site cabins;

On-site water storage tanks (provided by the drilling contractor) and portable skips for on-site refuse collection;

Erection of portable cabins providing temporary office accommodation, living accommodation for key personnel who need to be on-site to provide 24 hour supervision, canteen, toilet and shower facilities for the crews;

Noise attenuation and dust control procedures will operate on site including effective silencers and damping down the wellsite and access roads as the weather dictates;

Cessation of drilling, securing of the well and demobilisation of the drilling rig:

o In the event that the borehole encounters hydrocarbons the well will be temporarily suspended and secured through the installation of a cemented 7” liner coupled with inhibited kill weight fluid of sufficient weight (density) to assure that the hydrostatic pressure in the well at reservoir depth will be in excess of known reservoir pressure. The combination of cemented pressure tested casing, the fluid column and a pressure tested surface valve provides the required independent barriers between the reservoir and the environment. This is in compliance with accepted UK onshore best industry practices (as specified in Oil & Gas UK Guidelines) and Celtique’s Well Planning, Design and Operating Standards. The integrity of surface equipment will be protected through the maintenance of security at the well site through barriers and security guarding;

o In the event that hydrocarbons are not found, the well will be permanently sealed by setting a series of cement plugs to provide isolation of permeable horizons in accordance with accepted UK onshore “best practice” industry standards (Oil & Gas UK Guidelines for the Suspension & Abandonment of Wells, July 2012) and Celtique’s Well Planning, Design and Operating Standards. The site is then returned to its original condition:



Because of the technical constraints associated with the drilling and maintenance of an exploratory well, it is difficult to accurately estimate the time taken to complete the well. Worst case timing (allowing for operational contingencies) scenarios are estimated at:

Construction: 6 weeks;

Mobilisation & Drilling: 10 weeks;

Cessation of drilling and securing of well (7 days). Unless otherwise agreed in advance and in writing by the county planning authority, construction, drilling rig mobilisation and restoration phases of the development work at the site shall only be undertaken between the hours of 07:30 and 18:30 Mondays to Fridays and 08:00 to 13:00 on Saturdays. No work shall occur on Sundays, Bank holidays and public holidays. This condition does not relate to operations necessary for the 24 hours drilling and testing operations. The rig unit, mud pumps and all generators are enclosed in acoustic enclosures mitigating noise levels. Deliveries will be timed to avoid school drop off and pick up in local villages. Figure 2.1 below shows the position of the site in relation to the village of Broadford Bridge. Figure 2.2 shows the “start” and “end” points of the well in relation to the surface features around the well site. It is noted that while the most suitable surface location was selected for environmental reasons it was not directly above the target formation. Hence, in order to reach the target from the chosen surface location the well needs to be directionally drilled and terminates to the north of the drill site itself. This deviation can be thought of as the drilling of the well at a slight angle to the vertical (equivalent to an average of around 28

0 inclination). It is

emphasised that this is a directional well, NOT a vertical well with a horizontal sidetrack.



Figure 2.1: Site Location



Figure 2.2: “Start” and “End” well locations plotted on surface



3 Site Design and Operation A drawing of the proposed site set up during drilling is shown in Figure 3.1. The internal site surface will be formed with crushed stone compacted on top of an impermeable geotextile layer such as Bentomat or a HDPE membrane with a nominal fall to the perimeter interceptor ditch. A cross sectional view across the compound showing the impermeable geotextile membrane which protects the groundwater from any site leakages or spills is shown in Figure 3.2. The lining extends into the ditches and up the outer bunds to provide full containment of contaminants and surface water landing on the site. The compound is largely rectangular with a width (west to east) of approximately 55m and a length (north to south) of approximately 78m and is underlain by this impermeable geotextile layer which drains into an interceptor ditch. This interceptor ditch and retaining bund will be constructed around the compound to collect rain water runoff and contain any potential contaminants such as fuel and oils used in operating the site preparation and drilling machinery. This interceptor ditch is around 0.6 m deep and 1.5m wide and lined with the impermeable geotextile layer and has the ability to contain approximately 130m

3 (equivalent to around

130,000 litres) of fluid. Any liquids in this ditch prior to the installation of the rig on site provide informal water storage. Following the siting of the rig, all liquids in this interceptor ditch will be tankered off site for disposal to a registered disposal site or recycled into the drilling muds. In addition, any oil residue is tankered off site at the completion of the well for disposal at a registered disposal site. The cellar will be constructed in such a way as to avoid leaks from the cellar into the ground, using a system developed for building cellars in other sensitive locations. The concrete slab on site is formed with a slight gradient sloping towards the cellar. The cellar is sealed and the slab is on top of the impermeable geotextile layer that runs under the site so it is part of the overall larger impermeable site area. The surface water directed into the cellar can be either recycled into the drilling muds or disposed of off-site via a suction tanker to an authorised waste disposal facility

The rig is supplied by a double skinned diesel storage tank of up to 50,000 litres. The design of this double skinned (to provide secondary containment) diesel tank is in compliance with the Control of Pollution (Oil Storage) Regulations 2011. The diesel fuel tanks are located inside of the containment area. Inspection of this diesel storage container shall form part of the daily HSE inspection tour. In addition, there may be smaller tanks for the daily operation of the generators, situated on the generators themselves and provided with drip trays. Requirements for deliveries of diesel fuel and prevention of any leakage are covered by operational procedures and training.

There are also lubricants and hydraulic oils associated with the maintenance of the drill rig and associated equipment. They are anticipated to be mineral based and non-chlorinated. Separate storage areas with drip trays or secondary containment will be provided for all items and spill kits will be available to deal with any spillage. All containers will be clearly labelled to identify contents, toxicity and capacity of the storage containers and subject to daily HSE inspection.

Drilling additives (which improve the properties of the drilling fluid) are supplied in dry powder and liquid form and are located inside of the drill site containment area. Liquid additives are supplied in drums (typically holding either 25 litres or 208 litres) or intermediate bulk containers (IBC – typically holding around 1,000 litres) each with its own drip tray arrangement. A typical drilling operation may plan for around 10,000 litres of liquid additives. It is emphasised that not all additives will be on the site at any one time. In addition not all drilling additives will be used in the operation; some are on-site to address possible drilling contingencies which may not occur. However, even in the most conservative scenario where it is assumed that all liquid additives are on site at the same time, this maximum volume of around 10,000 litres of liquid drilling additive only equates to around 8% of the calculated volume of the interceptor ditch. Supplier’s Material Safety Data Sheets (MSDS) are retained on site for each additive. Each container shall be labelled and stored in accordance with the suppliers’ requirements and identified on the Pollution Incident Plan.

Refuelling activity will be in accordance with industry standard operating practices (e.g. PPG7 or equivalent). Refuelling activities from the delivery tanker to the main diesel container shall be a



supervised operation to prevent overfilling, poor connections and to respond to leaks in a timely manner. To prevent a pathway for diesel spills or leaks, secondary containment shall be located underneath connections and pipes to capture drips or leaks. In addition, spill kits will be provided by Celtique and will be kept available on location to deal with any small spills. The site layout shall be constructed to minimise the length of refuelling pipe from the tanker to the container. In the event of a spill the operations shall respond as per the Pollution Incident Plan. There is no underground storage of liquids or fuels within the pad. Drilling fluids (known as “drilling muds”) are stored at the rig site in above-ground steel tanks. A typical drilling rig layout is shown in Figure 3.1. The site is secured by a competent security contractor on a 24 hour basis with a perimeter fence line. All activity will be conducted within the site perimeter fence line.



Figure 3.1: Site During Drilling



Figure 3.2: Typical Site Cross Sections



4 Well Integrity & Groundwater Protection

4.1 Drilling & Groundwater Protection

The groundwater in the vicinity of the well is not used for domestic or industrial water supply. Notwithstanding this any groundwater is protected from the contents of the well during drilling and production operations by a combination of steel casing and cement sheaths, and other mechanical isolation devices installed as a part of the well construction process. The construction of the well is entirely directed to prevent the migration or transport of fluids across subsurface layers of impermeable rock formations that lie between the hydrocarbon producing formations and the groundwater, which themselves have isolated the groundwater over millions of years. The primary method used for protecting groundwater during drilling operations consists of installing a steel pipe, called casing, immediately after drilling through sensitive groundwater formations and cementing this steel pipe into place. The cement is pumped in slurry form down the inside of the casing and rises up through the annular space between the drilled hole and the casing, and once in place sets hard. The steel casing protects the zones from material inside the wellbore during subsequent drilling operations and, in combination with other steel casing and cement sheaths that are subsequently installed, protects the groundwater with multiple layers of protection for the life of the well. A typical design of a general well is shown in Figure 4.1 Figure 4.1: Well Design Schematic

The proposed well plan for Broadford Bridge-1 is shown in Figure 4.2 with typical depths as measured from the drill floor (measured depths - MD) for each set of casing. The figure also combines this information with geological and drilling fluid information to provide a simple overview of all key information relating to the borehole. The 20” conductor pipe will be either drilled or augured and grouted in place before the rig is moved onto location. This conductor is required to provide mud returns to the cellar while drilling the surface hole and prevent the cellar being washed out underneath the drilling rig.



Figure 4.2: Broadford Bridge-1 Well Plan:



A 171/2” vertical hole section will be drilled to about 2050 ft, through the Ashdown Beds and

some 50 ft into the Upper Purbeck Claystone. This section of the hole will be drilled with fresh water drilling fluid to minimize impact to any local aquifers expected to be encountered in the Lower Cretaceous formations. This freshwater drilling fluid will have to contain an additive to inhibit the reaction of the Weald, Grinstead and Wadhurst clays to the drilling fluid – these clays react to the presence of freshwater (resulting in clay dispersion and clay swelling in the borehole) substantially reducing the effectiveness of the drilling operation. In order to protect the local aquifers this borehole section will be drilled, cased and cemented quickly and efficiently. The 13⅜” casing will then be run into this hole to approximately 2050 ft and cemented back to the cellar using a single stage cement job to isolate and protect the Upper and Lower Tunbridge Wells Sand and Ashdown Sand aquifers. If cement is not to surface it will be necessary to perform a top job and ensure that the 13⅜” casing is grouted to the cellar floor to provide an effective seal. The wellhead is then installed on the top of the 13⅜" casing and this then support’s the drilling rig’s blow-out preventers (BOP) throughout the further drilling. The BOP is only ever for secondary well control in these operations; primary well control is provided by overbalancing the subsurface pressures by the hydrostatic pressure of the column of drilling fluid (or “mud”) used to drill the well. The complete BOP system will be tested as follows:

After installation of the wellhead and BOP system after running casing and before drilling out the shoe;

At regular intervals in compliance with API Guidelines ( typically between 14 to 21 days);

Prior to drilling into any anticipated hydrocarbon bearing formations or overpressured zones

Prior to any production tests where the BOPs remain in situ on the wellhead;

At any time the integrity of the BOP stack is in doubt (i.e. after any repairs, etc.). The 13⅜” casing shoe is drilled out together with 10 ft of new formation and a Formation Integrity Test (FIT) conducted. This test applies hydraulic pressure to the formation exposed below the casing shoe in stages, and is used to determine the strength of the formation below the shoe (this is a requirement for well control operations and does not involve the need for hydraulic fracturing). In addition, this test confirms that a hydraulic seal has been achieved from the casing shoe upwards. During the cementing operation, records are kept of all materials used, volumes pumped into the well and volumes returned from the well, in addition to a continuous recording of rates and pump pressures. Then the 12¼” hole is drilled to the top of the Upper Lias (a depth of approximately 6235 ft) using an Oil Base Mud at which point 9⅝” casing is then run and cemented to isolate the reactive Kimmeridge, Corallian and Oxford clays. Following the setting of the cement, an 8½" diameter drill bit is used to drill out of the bottom of this casing, and another FIT is conducted. Next, an 8½” hole is drilled through the Sherwood Sandstone to a total depth of around 9793 ft and (if hydrocarbons are found to be present) a 7” liner will be installed.

The cementing programme is designed as Celtique’s standard approach to providing life-of-well barriers, according to the Oil & Gas UK Well Integrity Guidelines. In this well the primary requirement is for a successful hydraulic seal to be obtained at the shoe since that is where the seal to the impermeable formation is required in order to isolate the overlying strata. The Cement Bond Log (CBL) is nonetheless taken over the production casing to provide a record of the cement bonding at the end of well construction. Any loss of drilling fluids to the formation shall be monitored by the Mud Logging Unit using a Pit Volume Totaliser (PVT) which sums the total fluid in the mud tanks using a float sensor. This shall be monitored throughout drilling. In the event of drilling fluid loss to the formation being identified by the PVT, controlling fluid leak-off to permeable formations is achieved with fluid loss control additives.



The selection of drilling fluids is based on the requirements for meeting the objectives of the current well. The purposes of the drilling fluid include the following:

Maintaining primary well control by overbalancing the native formation pressures, and this is achieved by adjustment of the drilling fluid density;

Lifting the drill cuttings from the bit out of the hole and thereby keeping the hole clean which is achieved by increasing the viscosity and gel strengths of the drilling fluid;

Maintaining borehole stability and controlling fluid leak-off to permeable formations, this is achieved with fluid loss control additives which may include drilling starch and ground marble (graded calcium carbonate) as a bridging agent, however details remain to be finalised with the Drilling Fluids contractor.

Drilling Fluids (referred to as drilling muds) to be used in the well are summarised in Table 4.1 and discussed below. Table 4.1: Drilling Fluids Summary

End Depth MD (ft)

Hole Size (inches)

Drilling Fluid Formation Fluid

200 26 Fresh water based Freshwater

2050 171/2 Water Based mud system with

clay inhibition Freshwater to brackish

aquifers

6235 121/4 Environmentally Compatible Oil

Based Mud System Saline Water

Non Ground water

9784 81/2 Environmentally Compatible Oil

Based Mud System Saline water

Possible gas or oil Non-ground water

Broadford Bridge 1 will initially penetrate the Weald Clay and the Upper and Lower Tunbridge Wells sands separated by the Grinstead Clay. The Upper and Lower Tunbridge Wells sands are classed as Secondary A aquifers by the Environment Agency and hence it is intended that these formations will be drilled with a clean, fresh water-based drilling fluid system in order to minimise the impact on these near-surface aquifers. However, there is evidence of clay swelling issues while drilling the Weald, Grinstead and Wadhurst clays and an additive (in the form of a chemical inhibitor to minimise the impact of these issues on hole stability) will be required to drill this section. Once this interval is cased off (13⅜” casing) with the shoe some 50 ft into the Upper Purbeck Claystone at 2050 ft measured depth (MD), drilling will resume with an Oil Based Mud system to the 9⅝” casing shoe, which is prognosed to be just into the top of the Lias at around 6235 ft MD. An 8½” hole will be drilled through the Lias utilizing the same OBM system through the Sherwood Sandstone to a total depth (TD) at 9793 ft MD (this equates to a total vertical depth sub-sea (TVDSS) of 8684 ft). The use of OBM in the 12 ¼ and 8 ½ inch hole sections will allow the most efficient stabilisation of the clays and shales in these sections of hole and will employ a mud system that can be recycled and reused. There is no injection of drilling fluids into any of the formations drilled and its impact is designed to be minimal on the formation being drilled affecting, generally, no more than a few inches of formation around the wellbore. Various drilling fluid compositions and drilling fluid weights (densities) will be used in each section of this well to reflect the varying needs to maintain a stable hole. The components of the drilling muds have been assessed with regard to their hazard to groundwater (under the EU Groundwater Directive) in a Hydrogeological Risk Assessment (Appendix 2 of document HSEC-BB-PD-04) and the drilling fluid shown to present a negligible risk to groundwater. This risk assessment and the drilling fluid composition (including relevant information from the MSDS sheets) has been shared with the Environment Agency.



Finally, it is noted that the borehole is designed and constructed in compliance with UK regulations (including the Offshore Installation and Wells (Design and Construction, etc.) Regulations 1996 and the Boreholes Sites and Operations Regulations 1995), Oil & Gas UK and UKOOG Guidelines and best industry practice (e.g. ISO and API standards). This design and construction is also subject to review by an independent, competent Well Examiner in compliance with UK Regulations (the Offshore Installation and Wells (Design and Construction, etc.) Regulations 1996) and supporting Guidance. The Health & Safety Executive’s (HSE) role in regulating the safety aspects of all drilling activity also mitigates environmental risks.

4.2 Rig Demobilisation

The rig demobilisation is the reverse process to the earlier mobilisation In the event that hydrocarbons are not found, the well will be permanently sealed to prevent, on a permanent basis, the escape or migration of fluids from the well and the site returned to its original condition. This involves a process of:

Pumping cement into the well to create a series of plugs;

Removal of the wellhead, cutting the casings and sealing them below ground level. No active pollution control requirements will be deployed. In the event that the borehole encounters hydrocarbons, the well will be temporarily suspended and the rig released. This temporary suspension will be carried out in compliance with regulatory and industry guidelines to leave the well in a safe state and allow a subsequent test of the reservoir to be made (this test will be the subject of a separate permit application and is not covered by this “drilling” permit documentation). This temporary suspension involves the following actions:

The last well construction operations with the drilling rig will leave the well with a 7 liner cemented in position extending from some 500 ft above the shoe of the 9⅝”" casing to TD;

The well will be filled with inhibited kill weight fluid of sufficient weight (density) to assure that the hydrostatic pressure in the well at the reservoir depth will be in excess of the known reservoir pressure. This combination of cement and fluid provides two independent pressure / isolation barriers between the reservoir and the environment;

In addition, the following actions will be implemented:

A kill string comprising of 27/8” tubing) will be run into the well to a depth of around 1000 ft;

A tubing hanger will be landed and a back pressure valve installed into the hanger profile and pressure tested;

All surface valves will be chained closed to prevent any tampering;

The integrity of surface equipment is assured by inspections and maintenance as required;

The security of the surface equipment is provided by security barriers at the well site and security guarding.

4.3 Groundwater Risk Assessment & Monitoring

The Environmental Statement (in section 11) summarises the groundwater risk assessment carried out based on the Source, Pathway, Receptor model as defined in the DEFRA Greenleaves III guidance. A summary of this detailed assessment is that:

There are no licensed surface water abstractions within 1km of the drill site;

The geological structure is such that the proposed exploratory borehole:



o Will not penetrate any of the Secondary Aquifers formed by the superficial deposits to the east;

o Will not encounter the Upper Tunbridge Wells Sand until a drilled depth of approximately 520 ft has been reached;

o May penetrate the Secondary Aquifers formed by the sandstone and limestone lenses within the Weald Clay but down-dip or cross-strike of any water supply boreholes that penetrate them.

There are no data on groundwater levels and flow in the area. However it may be inferred that:

o The Weald Clay materials directly beneath the drill site are likely to be characterised by a low overall permeability with little deep infiltration of rainfall and shallow down-slope interflow only;

o Groundwater in the superficial deposits and in the Secondary Aquifer sandstones and in the Weald Clay is locally recharged and characterised by a low overall throughput of water;

o Groundwater in the deeper Secondary Aquifers, starting with the Upper Tunbridge will be recharged on the outcrop area, which is some 10km to the north east and beyond; will flow southwards according to the regional dip of the strata; and has no practical connection with groundwater beneath the site or through which the proposed hydrocarbon exploratory borehole will penetrate.

Regarding the southerly groundwater flow in the deeper Secondary Aquifers, the actual depth of the aquifers beneath the drill site may be such that there is little actual groundwater movement in that area. Hydrochemical processes may then be such that the groundwater is of poor quality.

Taking into account the controls in place to manage risks, both this assessment concludes that:

The Proposed Development is to be drilled through a geological sequence that is well-

defined and understood. The inferred and recorded hydrogeological conditions accord with groundwater licensing records to indicate that that there are no principal aquifers present and no local reliance on groundwater for water supplies;

The risk of groundwater pollution is therefore inherently low but is reduced further by the incorporation of mitigation measures such as use of water-based, non-toxic drilling fluids when drilling through aquifers. Well abandonment proposals will ensure no such risk exists in the long-term.

In addition, a further Hydrogeological Risk Assessment (Appendix 2 of document HSEC-BB-PD-04) has also been carried out to assess, in greater detail, the potential risk to groundwater and concludes that the risk to groundwater from the well is negligible.

4.4 Surface Water Risk Assessment & Monitoring

The Environmental Statement (in section 11) summarises the surface risk assessment carried out based on the Source, Pathway, Receptor model as defined in the DEFRA Greenleaves III guidance. Taking into account baseline data and the controls in place to manage risks the assessment concludes that:

The risk of local ground and surface water contamination will be removed by well-engineered site preparation, including the use of impermeable geotextile linings and the capture of all surface runoff via an interceptor ditch system (the systems in place to provide this protection are described in section 3);

The slight risk of an effect on soil moisture in the nearby area of ancient woodland will be mitigated by drainage arrangement that allow upstream runoff to pass beneath the access road.

In addition:

Celtique shall implement its Waste Management Plan (described in reference document HSEC-BB-PD-04) which will minimise wastes generated from the borehole, minimise their



hazard potential, promote recovery of waste products and ensure their short and long term safe disposal. This plan is managed by the Site Drilling supervisor. The Site HSE Advisor will conduct inspections to assure compliance with the plan;

The development shall not commence until a scheme to dispose of foul and surface water (including details preventing surface water draining onto the public highway) has been submitted and approved by the West Sussex County Council Planning Authority (Planning Condition 22 of WSCC/052/12/WC planning approval);

The impermeable nature of the soils in the area mean that, even in the very unlikely event of a major spill which has the potential to impact surface waters, there is a negligible risk that such spills could impact aquifers. (the Pollution Incident Plan, which will be put in place to manage such unlikely scenarios, is summarised in section 6.2)

Consequently, because of the control arrangements in place to both prevent incidents and to mitigate their impact in the unlikely event that they occur and because of the impermeable nature of surface soils, surface incidents are not considered to have any impact on aquifers and there is no requirement for a water monitoring borehole.

However, to provide assurance that these arrangements do prevent impact to surface waters, a water monitoring programme will be implemented as summarised in section 5.3 and detailed in “Site Condition Report and Management & Monitoring Plan”, document number HSEC-BB-PD-03



5 Pollution Prevention and Monitoring 5.1 Pollution Prevention

The management of site activities shall be conducted in line with pollution prevention guidelines to prevent spillages or other incidents and protect environmental receptors (surface water, groundwater and atmosphere). These measures are described elsewhere in the document and include:

Measure to prevent surface spills and surface water pollution as described in section 3 and 4.4;

Measures to prevent downhole groundwater pollution as described in sections 4.1, 4.2 and 4.3.

As well as complying with all regulations and best industry practices, Celtique has designed and will operate the borehole in compliance with its Environmental Management System which is summarised in section 6. In the event that, regardless of the these controls, an environmental incident occurs, a Pollution Incident Plan (compliant with EA Guideline PPG21 – Incident Response Planning) will be in place – see section 6.2 for further information.

5.2 Environmental Baseline & Risk Assessment

The studies described in both the Environmental Statement and the “Site Condition Report and Management & Monitoring Plan” (document number HSEC-BB-PD-03) identify the environmental baseline as follows:

All of this area is represented by farmland which has no history of contaminative use;

There are no licensed surface water abstractions within 1km of the drill site;

Reference to the Natural England website indicates that there are no protected sites within influential distance of the drill site, the closest being >10km distant;

Reference to the EnviroInsight section of the Groundsure Report, commissioned by Celtique as part of the Environmental Statement confirms that there are no environmentally sensitive sites within 500m of the drill site boundary.

Given the distances to these sites from the drill site area, and the reliance of the sites on

factors that are unaffected by the drilling operation, no adverse impact on these protected

sites is anticipated.

The risk assessments contained in the Environmental Statement have been further refined by a separate Environmental Risk Assessment (Appendix 1 of the Waste Management Plan, document number HSEC-BB-PD-04) which concludes that, with the implementation of the arrangements and mitigating measures referenced in this document, the environmental risk posed by the borehole is negligible.

However, to provide continuing assurance of the effective implementation of these arrangements at the site, Celtique will also implement monitoring programmes for:

Surface water (section 5.3);

Noise (section 5.4).

These monitoring programmes will assess environmental performance against agreed baselines and are summarised in sections 5.3 and 5.4. Full details of the site monitoring plans are contained in document HSEC-BB-PD-03.

5.3 Surface Water Monitoring & Management

A site survey and inspection is detailed in section 3 of the Environmental Statement. In summary:



The River Adur runs in the vicinity of Broadford Bridge-1 and a north-east flowing tributary brook of the Adur is located on lower ground some 400m south east of the Drilling Site, and flows through Broadford Bridge;

There is a small pond 250m east of the Site, located in Prince’s Wood with a drainage outflow to the north that connects with another tributary of the River Adur;

Another small pond is located 200m north west of the Site, on the south western edge of Pocock’s Wood, with a further pond located 320m south of the Site in Gatewick Copse.

Celtique has agreed a Monitoring Scheme based on this site survey with the Environment Agency. In summary we propose that:

Samples will be taken from these locations to establish baseline conditions and any departure from them during and after the drilling works. The results will be benchmarked against Environment Quality Standards;

Precise locations will be identified based on field inspection to confirm proximity to the site, access issues, the direction of stream flow, and the down-gradient direction of potential runoff from the site;

Type 1 (field testing) and Type 2 (laboratory analyses) of the samples will take place as defined below:

o Type 1: On-site instrument-measured Temperature, Dissolved Oxygen, Electrical Conductivity, pH, Redox Potential, and Turbidity.

o Type 2: Sample recovery and laboratory chemical analysis for: Ammoniacal Nitrogen, Arsenic, Barium, Boron, Cadmium, Calcium, Chloride, Total Chromium, Copper, Lead, Magnesium, Mercury, Nickel, Potassium, Selenium, Sodium, Zinc, pH, PAH, EPH, GRO (BTEX), COD, TDS, Electrical Conductivity, and Alkalinity

The proposed sampling frequency of the monitoring programme is shown in Table 5.1 below.

Table 5.1: Sampling Frequency

Month Activity Type1 Frequency Type 2 Frequency Daily Inspection

*

1 Pre-Mobilisation

YES One sample, week 1


2 Site Establishment

YES Samples weeks 5 & 9


3 Drilling YES

Weekly on-site testing during drilling


YES

4 Drilling YES YES One sample,

week 15

YES

5 Demobilisation YES

One sample, week 19


6 None YES

One sample, week 23


Note:

* By site HSE Advisor to identify any changes in water quality (if flowing) at sample points.

5.4 Noise Monitoring & Management

The Environmental Statement, voluntarily submitted by Celtique Energie as part of the Planning Approval process identifies noise limits for the site and its surroundings.

As requested by the conditions of the Planning Approval from West Sussex County Council Authority (Planning Condition 08 of WSCC/052/12/WC planning approval) the development shall not commence until a Noise Management Plan has been prepared, submitted to the County Planning Authority for approval and implemented. The plan details the monitoring of the site throughout all phases of development, including night-time working and identifies the further mitigation actions which will be taken should such noise monitoring establish that the limits (as



specified in the Environmental Statement) are being exceeded. These further actions will include the documentation of details for further mitigation and a timetable for implementation which will be submitted to the County Planning Authority for approval and then implemented.

The West Sussex County Council Authority have primacy in approving this plan but, in the light of its importance, a summary of the submitted plan is included in the “Site Condition Report and Management & Monitoring Plan” – document number HSEC-BB-PD-03. In summary:

Noise measurements shall be undertaken by a suitably qualified person (possibly with the assistance of calibrated automatic monitoring equipment) at four identified noise sensitive locations. They shall be:

o Undertaken during a normal working day, during typical working hours, avoiding meal breaks and times when plant and equipment within the site or on the access road are not operational;

o Measured over a one-hour period during the normal working day, or over an appropriate time period if in response to specific complaints or ad hoc requests.

o They shall also be measured during a period when the site is not operational, for example during a lunch break or shift change, to enable a comparison to be made between the baseline and construction noise levels.

o At an initial frequency of once every week until it is agreed with the local planning authority that sufficient data has been accumulated to allow agreement that the monitoring frequency can be reduced to once every two to four weeks;

o Immediately after the implementation of any mitigation measures that have been implemented as a result of the Noise Monitoring Scheme or otherwise.

On completion of each noise survey a report shall be made available in a format suitable for submission to the local planning authority. The report shall be submitted within five working days of the scheduled date for monitoring.

If the agreed maximum noise levels are exceeded during a survey or a complaint is received from a local resident, an investigation shall be instigated within one working day to identify the cause of the non-compliance or complaint. Such an investigation may involve the identification and cessation of the activity or activities considered to be the cause of the non-compliance/complaint (where operationally safe to do so) and/or the investigation of mitigation measures to reduce the noise emission levels from the activity or activities, for example the replacement of noisy plant with quieter alternatives and/or the use of temporary screens. Any deviation from agreed working practices shall be identified immediately and conformance to the working practice reinstated.

A further noise survey shall be undertaken as soon as possible following the implementation of mitigation to re-assess the noise levels against the guideline noise levels.



6 Environmental Management 6.1 HSE Monitoring & Reporting

Celtique has developed and applies its integrated health, safety and environmental management system (HSE MS) to all of its operational activities. This approach is fully consistent with the requirements of the UK safety and environmental regulators and conforms to the principles of international standards such as ISO 14001 and OHSAS 18001. The implementation of this HSE MS will be achieved through documentation, competency of staff and contractors, the right HSE culture and an active programme of monitoring and review. The health and safety risks of all construction, drilling, testing and site restoration activities will be managed in compliance with the Borehole Sites & Regulations 1995, the Management of Health & Safety at Work Regulations 1992, the Construction (Design & Management) Regulations 2007, the Offshore Installations & Wells (Design & Construction etc.) Regulations 1996 and the company’s HSE Management System. The environmental risks of all construction, drilling, testing and site restoration activities will be managed, as summarised in this document, and in compliance with all environmental legislation (including: Groundwater Directive, Waste Management Permit, and relevant EA Pollution Prevention Guidelines (including PPG 5, 7, 18, 21 & 22)), West Sussex County Council Authority Planning Approval Conditions, best industry environmental practice and the company’s HSE Management System. Drilling and any subsequent testing operations will be conducted in accordance with good oilfield practice, all relevant controlling bodies and British and International Standards. Should any emergency situation occur the well would be instantaneously “shut in” by means of the fitted Blowout Preventer (BOP) during drilling operations or the Emergency Shut Down (ESD) system during production. The adoption of normal emergency procedures applicable to oilfield operations would ensure compliance with the UK onshore environmental and safety control regimes. Site specific Emergency Response Procedures will be put in place in consultation with the emergency services and tested prior to the commencement of any work (reference section 6.2). The HSE aspects of all site operations will be managed through both a Safety Management Plan (SMP) and an Environmental Management Plan (which will be incorporated onto a single overarching document, reference HSEC-BB-OP-01). The EMP will describe the mitigation measures to be put in place by Celtique Energie and its contractors throughout the works to minimise impacts on the environment. The EMP will also define who would be responsible for implementing each mitigation measure and contain a monitoring programme. As part of the site HSE organisational structure, a Celtique Site HSE Advisor will be assigned to the project for the duration of operations. The Site HSE Advisor will be supported by the Corporate HSE Advisor who reports into the Chief Operating Officer (COO). Day to day responsibilities can be summarised as:

The Site HSE Advisor is responsible for the method statement communication and continued support;

Operations are accountable for complying with the method statement, with the Drilling Supervisors/ Site Supervisor taking the lead for day to day accountability. As a minimum, daily tool box talks/morning briefings are held with operational personnel to communicate daily activities, HSE risks, reported incidents, near misses and other key information and time outs for safety are held as and when appropriate;

The Corporate HSE Advisor conduct inspections and provides coaching and further support to the Site HSE Advisor; ensuring that compliance with environmental best practice is reviewed, achieved or improved upon.



Documented inspections and audits are planned and implemented as detailed in the SMP and EMP as well as regular inspections by site HSE and operational teams, these include a programme of senior management site inspections to ensure compliance with Celtique’s HSE Management System. Regular environmental reports (at a frequency to be agreed with the Environmental Agency) shall be shared with the Environment Agency summarising results from monitoring activities. This shall include but not limited to:

Operations update;

Surface water report;

Noise report.

6.2 Emergency Preparedness & Response

To address the unlikely event of an emergency on site, Celtique will develop emergency response plans in conjunction with the Drilling Contractor and utilising a Management Systems Bridging Document (reference HSEC-BB-OP-03) to ensure that all companies involved in an emergency response are aligned. These plans will cover safety and environmental responses to emergencies, all relevant personnel will be trained in their response roles and exercises will be held to verify competencies. They will include a Pollution Incident Plan which will be developed specifically for an environmental / pollution emergency and submitted to the Environmental Agency for inspection. This plan will identify the resources (people and equipment) in place to respond to and clean up pollution incidents. The Drilling Supervisor/ Site Supervisor will coordinate the response from a site perspective to implement this plan. It shall be tested within the first week of operations. Specific pollution issues addressed in the plan include:

a) Fire Fighting Water: The Drilling Supervisor is responsible for coordinating the site response to any fire in line with the site emergency response plan. The first priority is the health and safety of personnel. The Drilling Supervisor/ Site Supervisor, or an employee with the delegated authority, shall report the incident to Celtique Energie’s Senior Management who will in turn notify the authorities (Environment Agency, Local Authority) of the incident, if required.

The safety of the site is effectively managed and fires are unlikely to occur. Any that do occur are likely to be small and capable of being extinguished by the site’s portable fire fighting equipment. The run off from the use of such extinguishers will remain within the rig containment area (in the bunds) and there will no pollution impact.

In the very unlikely event of a major fire, site firewater tanks are located near the main entrance to the well site compound (as required by West Sussex County Council Authority Planning Approval Condition 21) and external fire fighting resources will be requested to support the sites own fire team. These additional resources will have been identified in the response plan and contact made with the relevant fire brigade. While the use of such fire fighting water will initially be contained in the rig containment area, a 24 hour spill response contractor shall be contacted and deployed to support the continuing containment of such water (as required by PPG18). Contact details of contractor shall be located on the Pollution Incident Plan. Contractor shall also be briefed on the site Pollution Incident Plan.

b) Suspension of Operations: In the event of a safety incident on the rig or in the event of a breach of site security the drilling will be temporarily halted. In the event that such incidents require a short term suspension of operations the following controls will be implemented to prevent pollution:

o Stop drilling and pull bit back inside casing shoe;

o Continue to circulate while monitoring mud returns until incident is resolved;

o Monitor pit levels and address any losses/gains.

c) Spill Management: The use and transfer of liquids, e.g. chemicals, oils, fuels, shall be carried out with secondary containment (e.g. drip trays) in line with PPG7. The site will have a range of spill kits located around the site to provide rapid response to spillages. Before the start of operations, all personnel shall be briefed in the use and location of spill kits.



Each spill shall be cleaned up immediately and reported via the incident reporting system, regardless of size. As part of the daily HSE tour, each spill kit shall be examined to ensure it is still fit for purpose. In the very unlikely event of a large scale spill the impermeable membrane shall provide the principal source of containment. If further support is required for such an unlikely incident, the Drilling Supervisor shall coordinate the spill response, which includes notifying the 24 hour spill response contractor to support the clean-up of the spill. Details of the spill response contractor will be located on the Pollution Incident Plan. When contacting the spill response contractor, key information will include the estimated quantity and the contents (oil, muds, chemicals) of the spill. Celtique Energie shall respond to a spill as summarised below and as detailed in the oil spill response plans:

o STOP / CONTAIN: Site personnel to utilise spill mats and sandbags to contain spill; o NOTIFY: Site personnel contact Emergency Response contractor for spill management

and clean up if required; o NOTIFY: Site personnel contact Celtique Energie senior management who will in turn

contact EA; o REPORT: Celetique Energie complete incident report form (with investigation from HSE

team if required).

In the unlikely event of a large scale spill which requires the deployment of a spill response contractor, sampling of the local surface water shall be carried out for a minimum of 1 week after the spill or until agreed with the Environment Agency.

d) Spill on Access or Egress Road/Off Site: As a minimum, all liquid transfer of fuels, wastes or chemicals are expected to be transferred with spill kits. The 24 hour spill response contractor will be available to manage spillages off site as well as on site and also has the capability of supplying and utilising booms for use on land and water.

The Site HSE Advisor will carry out recorded spot checks on vehicles entering and leaving the site for spill kits.

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