The Celtic peoples and groundwater • Introduction • Groundwater in the Celtic regions • Groundwater and the environment • Groundwater in headwaters: hydrological and ecological significance • “Uisge Mèinne”: mine water hydrogeology in the Celtic lands, from Kernow (Cornwall, UK) to Ceap Breattain (Cape Breton, Canada) • Groundwater protection. Groundwater protection in a Celtic region: the Irish example • Groundwater protection in Scotland • Groundwater vulnerability mapping in Scotland: modifications to classification used in England and Wales • Groundwater management and protection in karst aquifers. Interdependence of groundwater and surface water in lowland karst areas of western Ireland: management issues arising from water and contaminant transfers • Groundwater protection zone delineation at a large karst spring in western Ireland • Groundwater resources and vulnerability in the Cretaceous Chalk of Northern Ireland • Influent rivers: a pollution threat to Schwyll Spring, South Wales? • Quaternary aquifers: resource evaluation and development. Shallow groundwater in drift and Lower Palaeozoic bedrock: the Afon Teifi valley in west Wales • Public water supplies from alluvial and glacial deposits in northern Scotland • Groundwater resources in the Quaternary deposits and Lower Palaeozoic bedrock of the Rheidol catchment, west Wales • Groundwater evaluation in data-scarce aquifers. Conceptual modelling of data-scarce aquifers in Scotland: the sandstone aquifers of Fife and Dumfries • QSC graphs: an aid to classification of data-poor aquifers in Ireland • The Triassic Sherwood Sandstone aquifer in Northern Ireland: constraint of a groundwater flow model for resource management • Modelling the potential impact of climate change on a shallow coastal aquifer in northern Scotland • Groundwater exploration in rural Scotland using geophysical techniques • Some case histories of geophysical downhole logging to examine borehole site and regional groundwater movement in Celtic regions • Groundwater supplies to island communities. The water resources of Bardsey, north Wales • Role of Geographical Information Systems and groundwater modelling in water resources management for small islands: a case study from St Martin’s and St Agnes, Isles of Scilly, UK • Index. Principal authors: C. N. O’Dochartaigh, University of Glasgow, UK. N. S. Robins, British Geological Survey, UK. C. Soulsby, University of Aberdeen, UK. P. L. Younger, University of Newcastle, UK. B. D. R. Misstear, University of Dublin, Ireland. I. A. Fox, SEPA Borders Office, UK. M. A. Lewis, British Geological Survey, UK. C. Coxon, University of Dublin, Ireland. J. Deakin, Geological Survey of Ireland, Ireland. S. Barnes, SITA, UK. S. L. Hobbs, Enviros Aspinwall, UK. C. R. C. Jones, Mott MacDonald, UK. K. Hiscock, University of East Anglia, UK. I Gaus, British Geological Survey, UK. G. Wright, Geological Survey of Ireland, Ireland. G. W. McNeill, The Queen’s University of Belfast, UK. R. Malcolm, University of Aberdeen, UK. A. M. MacDonald, British Geological Survey, UK. D. K. Buckley, British Geological Survey, UK. M. M. Webb, University of Wales, UK. D. C. Watkins, University of Exeter, UK.