Baseline Report Series: 22. the Carboniferous Limestone of Northern England

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Baseline Report Series: 22. the Carboniferous Limestone of Northern England Baseline Report Series: 22. The Carboniferous Limestone of Northern England Groundwater Systems and Water Quality Commissioned Report CR/05/076N Science Group: Air, Land & Water Technical Report NC/99/74/22 The Natural Quality of Groundwater in England and Wales A joint programme of research by the British Geological Survey and the Environment Agency BRITISH GEOLOGICAL SURVEY Commissioned Report CR/05/076N ENVIRONMENT AGENCY Science Group: Air, Land & Water Technical Report NC/99/74/22 This report is the result of a study Baseline Report Series: jointly funded by the British Geological Survey’s National Groundwater Survey and the 22. The Carboniferous Limestone of Environment Agency Science Group. No part of this work may be Northern England reproduced or transmitted in any form or by any means, or stored in a retrieval system of any nature, without the prior C Abesser, P Shand & J Ingram permission of the copyright proprietors. All rights are reserved by the copyright proprietors. Contributors Disclaimer The officers, servants or agents of both the British Geological Survey and the R Hargreaves (GIS) & M Moreau (Sampling) Environment Agency accept no liability whatsoever for loss or damage arising from the interpretation or use of the information, or reliance on the views contained herein. Environment Agency Dissemination status Internal: Release to Regions External: Public Domain ISBN: 978-1-84432-647-1 Product code: SCHO0207BLYT-E-P ©Environment Agency, 2005 Statement of use This document forms one of a series of reports describing the baseline chemistry of selected reference aquifers in England and Wales. Cover illustration Giggleswick Scar, photo taken from Settle Golf Course, Giggleswick [SD3809 4648] Key words Environment Agency Project Manager: Baseline, Carboniferous Limestone, Yorkshire, Lancashire, Pennines, water quality, hydrogeochemistry, UK Dr Sean Burke aquifer. Science Group: Air, Land & Water Bibliographic Reference British Geological Survey Project Manager: ABESSER, C, SHAND, P. & INGRAM, J, 2005. Baseline Report Dr Paul Shand Series: 22. The Carboniferous Groundwater Systems & Water Quality Programme Limestone of Northern England. British Geological Survey Commissioned Report No. CR/05/076N Environment Agency Science Group, Solihull 2005 ©Environment Agency 2005 British Geological Survey, Keyworth, Nottingham 2005 ©NERC 2005 BRITISH GEOLOGICAL SURVEY ENVIRONMENT AGENCY The full range of Survey publications is available from BGS The Environment Agency is the leading public body protecting Sales Desk at the Survey headquarters, Keyworth, Nottingham. and improving the environment in England and Wales. The more popular maps and books may be purchased from BGS-approved stockists and agents and over the counter at the It's our job to make sure that air, land and water are looked after by Bookshop, Gallert 37, Natural History Museum, (Earth everyone in today’s society, so that tomorrow’s generations inherit Galleries), Cromwell Road, London. Sales. Sales Desks are a cleaner, healthier world. also located at the BGS London Information Office, and at Murchison House, Edinburgh. 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Further copies of this report are available from the Environment The British Geological Survey carries out the geological Agency's National Customer Contact Centre by emailing: survey of Great Britain and Northern Ireland (the latter as an [email protected] agency service for the government of Northern Ireland), and of or by telephoning 08708 506506. the surrounding continental shelf, as well as its basic research projects. It also undertakes programmes of British technical aid in geology in developing countries as arranged by the Department for International Development and other agencies. Environment Agency Regional Offices The British Geological Survey is a component body of the Anglian Natural Environment Research Council. Kingfisher House, Goldhay Way, Orton Goldhay, Peterborough PE2 5ZR Keyworth, Nottingham NG12 5GG Tel 01733 371811 Fax 01733 231840 0115 936 3100 Telex 378173 BGSKEY G Fax 0115 936 3200 Midlands e-mail: [email protected] www.bgs.ac.uk Sapphire East, 550 Streetsbrook Road, Solihull, West Midlands B91 1QT Murchison House, West Mains Road, Edinburgh, EH9 3LA Tel 0121 711 2324 Fax 0121 711 5824 0131 667 1000 Telex 727343 SEISED G Fax 0131 668 2683 North East Rivers House, 21 Park Square South, Leeds LS1 2QG London Information Office at the Natural History Museum, Tel 0113 244 0191 Fax 0113 246 1889 Earth Galleries, Exhibition Road, South Kensington, London, SW7 2DE North West 0207 589 4090 Fax 0207 584 8270 Richard Fairclough House, Knutsford Road, Warrington WA4 1HG 0207 938 9056/57 Tel 01925 653999 Fax 01925 415961 St Just, 30 Pennsylvania Road, Exeter EX4 6BX South West 01392 278312 Fax 01392 437505 Manley House, Kestrel Way, Exeter EX2 7LQ Tel 01392 444000 Fax 01392 444238 Geological Survey of Northern Ireland, 20 College Gardens, Belfast BT9 6BS Southern 01232 666595 Fax 01232 662835 Guildbourne House, Chatsworth Rd, Worthing, Sussex BN11 1LD Tel 01903 832000 Fax 01903 821832 Maclean Building, Crowmarsh Gifford, Wallingford, Oxfordshire OX10 8BB Thames 01491 838800 Fax 01491 692345 Kings Meadow House, Kings Meadow Road, Reading RG1 8DQ email: [email protected] Tel 0118 953 5000 Fax 0118 950 0388 Parent Body Environment Agency Wales Natural Environment Research Council 29 Newport Road, Cardiff CF24 0TP Polaris House, North Star Avenue, Swindon, Wiltshire Tel 01222 770088 Fax 01222 798555 SN2 1EU 01793 411500 Telex 444293 ENVRE G Fax 01793 411501 Contents FOREWORD v BACKGROUND TO THE BASELINE PROJECT vi 1. EXECUTIVE SUMMARY 1 2. PERSPECTIVE 2 3. BACKGROUND TO UNDERSTANDING BASELINE QUALITY 6 3.1 Introduction 6 3.2 Geology 6 3.3 Hydrogeology 13 3.4 Aquifer mineralogy 15 3.5 Rainfall chemistry 17 3.6 Landuse in the area 18 4. DATA AND INTERPRETATION 19 4.1 Project sampling programme 19 4.2 Historical data 19 4.3 Interpretation of groundwater samples 20 4.4 Data handling 20 5. HYDROCHEMICAL CHARACTERISTICS 21 5.1 Introduction 21 5.2 Water types and physicochemical characteristics 23 5.3 Major elements 23 5.4 Minor and trace elements 27 5.5 Pollution indicators 28 6. GEOCHEMICAL CONTROLS AND REGIONAL CHARACTERISTICS 29 6.1 Introduction 29 6.2 Depth variations 29 6.3 Temporal variations 32 6.4 Age of groundwater 34 6.5 Spatial variations 35 7. BASELINE CHEMISTRY OF THE AQUIFER 50 8. SUMMARY AND CONCLUSIONS 52 9. REFERENCES 53 i List of Figures Figure 2.1 Topography and Surface drainage of the study area 3 Figure 2.2 Landuse in the study area 4 Figure 2.3 Limestone quarrying in the study area, Stainton Quarry [BNG 32470 47271] 5 Figure 3.1 Geology of the study area 7 Figure 3.2 Drift deposits in the study area 8 Figure 3.3 Outcrops of Dinantian rocks and principal structural features of the Dinantian Palaeogeography of the study region and surrounding areas (Aitkenhead et al., 2002) 9 Figure 3.4 Schematic cross-section of the Askrigg Block (after Wilson, 1992, in Aitkenhead et al., 2002) 10 Figure 3.5 Generalised vertical sections of the Dinantian strata of the Askrigg Block, Craven Basin and Derbyshire Dome (Aitkenhead et al., 2002) 12 Figure 3.6 Distribution of outcrops of various Carboniferous Limestone lithologies in Northern England (Jones et al., 2000) 14 Figure 3.7 Photomicrographs illustrating the progressive dolomitization and chertification of the Pendleside Formation. The width of each photomicrograph = 0.571 mm. 16 Figure 5.1 PIPER Plot showing the relative concentrations of major cations and anions in the carboniferous limestone groundwaters 23 Figure 5.2 Range of (a) major ion concentrations and (b) minor and trace element concentrations in the Carboniferous Limestone groundwaters. Black line = seawater line (normalised for median Cl). Grey line = detection limit for individual elements 25 Figure 5.3 Cumulative Probability plot of (a) major ion concentrations and (b) minor and trace element concentrations in the Carboniferous Limestone groundwaters 26 Figure 6.1 Depth variations of pH and concentrations of Ca, Mg, K, SO4, Si Cl and Sr in the groundwaters 30 Figure 6.2 Variations in NO3-N, Dissolved Oxygen, F, Br, Mn and Fe concentrations with borehole depth 31 Figure 6.3 Relationship between pH and calcite saturation in the Carboniferous Limestone groundwaters 32 Figure 6.4 Inverse relationship between NO3-N and NH4-N in the groundwaters of the Carboniferous Limestone aquifer 33 Figure 6.5 Temporal variations in groundwater chemistry of the Carboniferous Limestone aquifer 33 13 Figure 6.6 Relationship between δ C and depths 34 Figure 6.7 Relationship between Ca and Mg concentrations and calcite/dolomite saturation in the groundwater 35 Figure 6.8 Relationship between borehole depths and calcite/dolomite saturation in the groundwaters 36 Figure 6.9
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