Borehole Construction Report R4 Revised Sept 17
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KM8 MONITORING BOREHOLES AS BUILT CONSTRUCTION REPORT KM8 WELL, KIRBY MISPERTON A WELLSITE, NORTH YORKSHIRE For Third Energy UK Gas Limited Knapton Generating Station East Knapton Malton North Yorkshire YO17 8JF By Envireau Water Aske Stables Aske Tel: 01748 889 268 Richmond E mail: [email protected] North Yorkshire Web: www.envireauwater.co.uk DL10 5HG Ref: P:\Third Energy KMA (1996)\40 - Reporting\PreOp Conditions\PO4\Borehole Construction Report r4.docx September 2017 TABLE OF CONTENTS 1 INTRODUCTION .......................................................................................................................................... 1 2 KMA WELLSITE MONITORING BOREHOLES. .............................................................................................. 2 2.1 Location .............................................................................................................................................. 2 2.2 Construction Details ........................................................................................................................... 2 2.3 Geological Sequence .......................................................................................................................... 2 2.4 Borehole Development ...................................................................................................................... 6 2.5 Groundwater Levels on Completion .................................................................................................. 6 2.6 Field Water Chemistry ....................................................................................................................... 6 2.7 WR-38 Borehole Record Forms .......................................................................................................... 6 FIGURES Figure 1 KM8 Monitoring Borehole Locations Figure 2 As built – Shallow Monitoring Boreholes Figure 3 As built – Intermediate Monitoring Borehole (BHD) Figure 4 As built – Deep Monitoring Borehole (BHE) TABLES Table 1 Borehole Coordinates and Elevations (OSGB 36) Table 2 Borehole Construction Details Table 3 Geological Sequence Table 4 Field Water Chemistry Results APPENDICES Appendix A Borehole Locations Survey Map Appendix B Driller’s logs Appendix C WR-38 Borehole Record Forms © Envireau Ltd. 2017 Envireau Ltd. Registered in England & Wales No. 6647619. Registered office: Cedars Farm Barn, Market Street, Draycott, Derbyshire, DE72 3NB, UK. Any report provided by Envireau Ltd. is for the client's use and may be reproduced by the client for internal use. The report must not be issued to third parties without the express written consent of Envireau Ltd. If the report is released to any third party, Envireau Ltd will not accept responsibility or liability of any nature to that third party to whom the report (or part thereof) is released. Moreover, Envireau Ltd will accept no liability for damage or loss as a result of any report being made known to, or relied upon by, a third party, unless expressly agreed with Envireau Ltd in writing. Revision Details Completed by Date Checked by Date REV01 1st Draft AB 12/05/2016 PH 12/05/2016 REV02 Final JS 26/07/2016 PH 26/07/2016 REV03 Update after discussion with EA JS/PH 27/06/2017 PH 28/06/2017 REV04 Reissue after discussion with EA JS 05/09/2017 PH 08/09/2017 Ref: P:\Third Energy KMA (1996)\40 - Reporting\PreOp Conditions\PO4\Borehole Construction Report r4.docx September 2017 MONITORING BOREHOLES CONSTRUCTION REPORT KM8 WELL, KIRBY MISPERTON A WELLSITE, NORTH YORKSHIRE 1 INTRODUCTION Third Energy UK Gas Limited (Third Energy) is proposing to hydraulically fracture an existing hydrocarbon production well (KM8) at Kirby Misperton A Wellsite, North Yorkshire (“the KMA wellsite”). To comply with the Environment Agency requirement to establish a water quality baseline ahead of the proposed hydraulic fracturing, five (5) monitoring boreholes were constructed at the KMA wellsite in December 2015, as follows: • Three (3) shallow boreholes (BHA, BHB, BHC) targeting the superficial deposits/weathered zone of the Kimmeridge Clay Formation. • One (1) intermediate borehole (BHD) targeting the un-weathered Kimmeridge Clay Formation/Ampthill Clay Formation (Ancholme Group). • One (1) deep borehole (BHE) targeting the top ~30m of the Corallian Group. A mining waste and groundwater activity permit (Ref. EPR/DB3002HE) was issued by the Environment Agency for the hydraulic fracturing operation in April 2016. The permit includes five pre-operational measures (PO1 – PO5). PO4 states: Prior to the operation of the regulated facility the operator shall provide a written report that provides the following information for each groundwater monitoring borehole installed: (a) casing/linings (length, diameter, material, type of grout or filter media and whether slotted or plain); (b) depths and diameters of unlined sections; (c) records of groundwater ingress during construction and standing groundwater levels on completion; (d) details of strata encountered during drilling; (e) reference levels for the individual criteria specified in 4(a) to (c) above in metres above ordnance datum; (f) a location plan at a suitable scale showing the boreholes in relation to the point of discharge; (g) national grid references of the boreholes in the form AB 12345 67890 any other information obtained from the boreholes relevant to the interpretation of water sample analysis. This report has been prepared by Envireau Water to fulfil the requirements of PO4 and is intended to be submitted to the Environment Agency prior to the hydraulic fracturing operation. Please note that this report does not provide a description of the regional geology and hydrogeology, which is covered in detail in the Hydrogeological Risk Assessment that was prepared by Envireau Water in May 2015 [Ref. 1]. North Office, Aske Stables, Aske, t 01748 889268 e [email protected] Richmond, North Yorkshire, DL10 5HG w www.envireauwater.co.uk Envireau Ltd. Registered in England & Wales No. 6647619 Registered office: Cedars Farm Barn, Market Street, Draycott, Derbyshire, DE72 3NB Envireau Water 2 KMA WELLSITE MONITORING BOREHOLES. 2.1 Location The location of the five wellsite monitoring boreholes is presented on a site layout plan on Figure 1. Also shown on Figure 1 is the location of the point of discharge. Table 1 below presents the surveyed borehole coordinates including ground and wellhead elevations to Ordnance Datum. The surveying map is presented in Appendix A. Table 1: Borehole Coordinates and Elevations (OSGB 36) Ground Elevation Top of Wellhead Borehole ID National Grid Reference (NGR) (mAOD) Elevation (mAOD) BHA SE 77153 79025 31.69 32.34 BHB SE 77099 78989 31.98 32.55 BHC SE 77162 78964 31.87 32.31 BHD SE 77132 78963 29.01 29.64 BHE SE 77110 78969 28.94 29.73* *Top of wellhead taken as the top of the borehole cover. When open, the lower stub flange is at 29.71mAOD 2.2 Construction Details The monitoring boreholes were constructed by Magpie Environmental Drilling Ltd, with Envireau Water providing technical support when required. The construction of the monitoring boreholes commenced on the 27 November 2015 and was completed on the 9 December 2015. The final depth of all the boreholes was based on the observed geological sequence and was agreed with the Environment Agency prior to completion. The driller’s logs are provided in Appendix B. Summary construction details are presented in Table 2 below together with records of groundwater ingress (water strikes) during construction and groundwater levels on completion. 2.3 Geological Sequence The geological sequence has been determined by Envireau Water based on the logging of recovered drilling returns. The geology encountered is summarised in Table 3 below and presented on the borehole construction diagrams on Figures 2, 3 and 4. The geological sequence at the KMA wellsite consists of made ground / top soil up to 4 meters in depth, overlying mudstone and clay of the Kimmeridge Clay Formation/Ampthill Clay Formation (Ancholme Group) to a depth of approximately 177mbgl. The Ancholme Group is underlain by oolitic limestone of the Corallian Group. The transition between the Ancholme Group and the Corallian Group is not abrupt and appears to occur over a depth between 177mgl and 190mbgl. Ref: P:\Third Energy KMA (1996)\40 - Reporting\PreOp Conditions\PO4\Borehole Construction Report r4.docx Page 2 of 6 Rev: 08/09/2017 12:31 Envireau Water Table 2: Borehole Construction Details Borehole Rest Water Level Completion Depth Drill Diameter Casing Details Filter Pack Details Water Strikes ID (mbtow) (mAOD) BHA 11.5mbgl 254mm (10”) from 0 50mm ND uPVC casing. Cement from 0 to 0.5mbgl (31.9 to 11.2mbgl 9.04 on 23.27 (20.4mAOD) to 12.0mbgl (31.9 to 31.4mAOD) (20.7mAOD) 20/04/2016 19.9mAOD) Blank from 0 to 8.0mbgl (31.9 to 23.9mAOD) Bentonite pellets from 0.5 to 6.7mbgl (31.4 to 25.2mAOD) Slotted section from 8.0 to 11.0mbgl (23.9 to 20.9mAOD) Sand blinding layer from 6.7 to 7mbgl (25.2 to 24.9mAOD) Blank section from 11.0 to 11.5mbgl (20.9 to 20.4mAOD) 2-4mm Gravel from 7 to 11.5mbgl 24.9 to 20.4mAOD) BHB 11.5mbgl 254mm (10”) from 0 50mm ND uPVC casing. Cement from 0 to 0.5mbgl (32 to 11.3mbgl 9.52 on 23.03 (20.5mAOD) to 12.0mbgl (32.0 to 31.5mAOD) (20.7mAOD) 20/04/2016 20.0mAOD) Blank from 0 to 8.0mbgl (32.0 to 24.0mAOD) Bentonite pellets from 0.5 to 6.7mbgl (31.5 to 25.3mAOD) Slotted section from 8.0 to 11.0mbgl (24.0 to 21.0mAOD) Sand blinding layer from 6.7 to 7mbgl (25.3 to 25.0mAOD) Blank section from 11.0