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GSI Metadata National Draft Vulnerability Data/Groundwater Protection Schemes |
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1. Metadata Reference (GSI_GWPS)
Metadata Date (dd/mm/yyyy) : 30/08/2005
Last Date (dd/mm/yyyy): 24/01/2006
2. Indentification Information
Title : Groundwater Protection Schemes dataset
Description : The dataset comprises aerial coverages, on a County basis, of groundwater vulnerability, aquifer category, bedrock boundaries, hydrogeological data, subsoils data, depth to bedrock data, source protection areas, Groundwater Protection Zones, and Groundwater Protection Responses. The Groundwater Protection Responses currently comprise those for landfills, on-site wastewater treatment systems for septic tanks, and IPC Land spreading. There are nine (9) sets of maps for full GWPSs. There is a report accompanying the maps, a report discussing water quality, and reports for individual water supply source studies.
The vulnerability, aquifer and source protection area datasets combined to provide a generalised interpretation of the risk to groundwater quality from human activities in a particular area. The risk is defined by Groundwater Protection Zone codes, and can be used in the planning process to determine:
Requirements for ground conditions and engineering measures over and above normal ‘best practice’ requirements, and/or
The scale of site investigation required and/or
Short-lists of potentially suitable sites.
The Groundwater Protection Responses provide more detailed recommendations of specific requirements for certain key human activities, and are based on the Groundwater Protection Zone definition of risk in a particular area. More detailed explanations can be found at http://www.gsi.ie/Programmes/Groundwater/Projects/Protection+Schemes+Guidelines.htm#responses
Groundwater Protection Schemes have been done for the following counties: Clare, South Cork, Donegal, Kildare, Kilkenny, Laois, Limerick, Meath, Monaghan, Offaly, Roscommon, Tipperary (North Riding), Tipperary (South Riding), Waterford, Wicklow, Bog of the Ring (Fingal , Co.Dublin) , Carlow, Cavan and Galway (in process). Groundwater Protection Schemes (DELG/EPA/GSI, 1999).
Keywords: Groundwater Protection Schemes Reports, Source Reports, Executive summary, Risk Management, Groundwater Protection Zones, Land Surface Zoning, Groundwater Protection Zones, Groundwater Protection Response, Source Protection Areas, Zone Of Contribution (Zoc), Aquifers, Groundwater Vulnerability, Assessment of the quality of public groundwater supplies, Boreholes, Wells, Karst, On-Site wastewater treatment systems, IPC Landspreading, Landfill, Susoils, Land surface.
Version : 1.0
Language: English
Data type : vector, paper
3. Lineage Information
Originator org- The Groundwater Section in the GSI.
Other contributors - The Department of the Environment and Local Government, the Environmental Protection Agency.
Technical contact details - Silvia Caloca.
Principle data capture Technique - Started in 1996. Information taken from the OSi 1:50k Discovery Series, 1:10,560 sheets (6 inch sheets), and 1:126,720 sheets are used to give information on streams, contour, springs and outcrops. Information is also compiled from literature and company records, local authorities, well drillers, consultants’ records, Land Commission records, and GSI field investigations. The main data sources during the updating stage are: information acquired during field investigation, data from local authority well grants, and consultants’ records .
4. Lineage Records.
Filename: Groundwater Protection Schemes
Date (dd/mm/yyyy): 1996
Originator.- Geological Survey of Ireland.
Nature of change/update to data
Development of Groundwater Protection Scheme which provides guidelines for the planning and licensing authorities in carrying out their functions, and a framework to assist in decision-making on the location, nature and control of developments and activities in order to protect groundwater.
Methodology.-
These maps have been compiled from a variety of sources. Some of the maps were created using modern reconnaissance mapping techniques while others are desk compilations only. Most of the maps have been first of all digitized in AutoCAD at the 1:50,000 Scale using a tablet, others maps were created by heads up digitizing of georeferenced images. Most maps were migrated from AutoCAD into ESRI (shapefile) and MapInfo (tab files) . F format s.
Sources Used as input Data for the change /update.-
Main data sources during the data compilation stage were: maps of varying scales:
The 1; 50,000 maps are excellent at giving information on streams and topography. The 1:10,560 maps give more detailed information on surface water features, including springs, and can indicate likely areas of shallow rock outcrop. Point features, which have been located by GPS systems, are projected using the National Irish Grid. Soils maps at the 1:126,720 scale and recently Soils maps from Teagasc at the 1:50,000 scale are also used, as well as the Bedrock geology 1:100,000 Scale Map Series.
Subsoils information provided by Teagasc and the Quaternary Section of the GSI.
Scripts/tools used.-
AutoCAD scripts and Build/Clean/Topologise and Geoprocessing tools in Arc GIS and MapInfo. .
Contact details for further information on scripts/Tools.-
Mairead Glennon, Groundwater Section, Geological Survey of Ireland, Beggars Bush, Haddington Road, Dublin 4.
5. File Structure and maintenance information
Authorised by: - Koen Verbruggen (IMP, Geological Survey of Ireland)
Maintenance/ Update frequency- Irregular
6. Data dictionary: File Name/Field Description/ Field
Aquifer.- any stratum or combination of strata that stores or transmits groundwater. (Local Government (Water Pollution) Act, 1990). More commonly: A permeable geological stratum or formation that can both store and transmit water in significant quantities.
Vulnerability.- A term used to represent the intrinsic geological and hydrogeological characteristics that determine the ease with which groundwater may be contaminated by human activities.
SPA.- The catchment area around a groundwater source which contributes water to that source (Zone of Contribution), divided into two areas; the Inner Protection Area (SI) and the Outer Protection Area (SO).
GPZ.- Zones delineated by integrating aquifer categories or source protection areas and associated vulnerability ratings. The zones are shown on a map, each zone being identified by a code e.g. SO/H (outer source area with a high vulnerability) or Rk/E (regionally important aquifer with an extreme vulnerability). Groundwater protection responses are assigned to these zones for different potentially polluting activities.
RPZ.- Resource Protection Zones. For any region, the area outside the SPAs can be subdivided, based on the value of the resource and the hydrogeological characteristics, into eight aquifer categories. The result of integrating the two regional elements of land surface zoning (vulnerability categories and resource protection areas).
Land surface.- zoning provides the general framework for a groundwater protection scheme.
Hydrogeology data .-Hydrological features in the area.
Bedrock Geology.- Bedrock Geology 1:100,000 scale Map Series.
Subsoils geology.- The material between the topsoil and the bedrock.
Outcrop and DTB.-Outcrop and Depth to Bedrock information
Landfill responses.- Groundwater Protection matrix Responses for Landfills;
On-Site wastewater treatment systems.- On-site wastewater treatment systems for single houses e.g. Septic Tank Systems
IPC Landspreading.- IPC land spreading of organic wastes.
7.Geographical information
Reference system: Irish National Grid
Spatial Extent: Whole of Republic of Ireland
Scale: 1:50,000
8. Distribution Information
Filename: Groundwater Protection Schemes dataset
Holder : Geological Survey of Ireland.
Distributor contract details:
Koen Verbruggen
Information Management Program
Geological Survey of Ireland,
Beggar's Bush,
Haddington Road ,
Dublin 4
Storage Format : AutoCAD, MapInfo and Arc View digital maps; MS Word and PDF reports.
Supply Format : Paper maps, CD Rom, Digital files via web.
Supply media : Paper maps, CD Rom, Digital files via web.
File size : 255.33 MB in Arc shapefiles.
Copyright : Use of the data are constrained only by the GSI GIS Data License Agreement
Other Restrictions : free via web else charge per map/ report.
9. Quality Ratings
Spatial Accuracy : Good five-figure E and N. automatically derived six-figure E and N. Positional errors of up to 500m have been observed in source datasets
Currency: Digital geometry and attributes are based on GW criteria of The Groundwater section. Therefore boundaries may change according to lithological or structural changes, or new information.
Thematic accuracy : correct names and classifications .
Logical consistency : Some GWPS maps are topologically correct but not all of the schemes are.