Describes the well drilling and construction details. OGC WaterML 2.2 Part 4 - GroundWaterML 2 is an OGC Standard. Copyright (c) 2016 Open Geospatial Consortium. To obtain additional rights of use, visit http://www.opengeospatial.org/legal/ . A material used for sealing the construction of a borehole or well. Material used in the sealing component of a water well. E.g. formation packer, welded ring, shale trap, drive shoe, driven casing, etc. Type of sealing. E.g. annular sealing, plugging, etc. Topmost component of a borehole construction. The elevation of the bore collar with CRS and UOM. Type of reference elevation, defined as a feature, e.g. Top of Casing, Ground, etc. Type of assembly bolted to the production casing to control the well, and to provide access and protection (e.g. from flooding, vandalism). Example: raised tube, covers, manhole, 'Gattick Cover' flush, concrete ring, etc. (after Fretwell, et al., 2006). The geographical location of the collar. Relation between a bore collar and its sealing parts. Characteristics of the borehole associated to a specific collar. Construction components of the well. These are particularly important when assessing results of pump tests. General term for a hole drilled in the ground for various purposes such extraction of a core, release of fluid, etc. The custodian of the drill core or samples recovered from the borehole. The geometries for the intervals from which core is extracted along the borehole. Date of drilling. The organisation responsible for drilling the borehole (as opposed to commissioning the borehole). Method of drilling. Type of borehole inclination, e.g. vertical or horizontal. Diameter of the borehole. Organisation responsible for commissioning the borehole (as opposed to drilling the borehole). Describes the location of the start of the borehole, e.g. ground surface. Relation between a borehole and its construction components. Relation between a borehole and its collar, which represents the top construction component of the borehole. Relation designating the equipment installed in a borehole. Elements used in borehole construction. Position of the top (nearest to the surface) of the component Position of the bottom (farthest to the surface) of the component Collection of filtration components used to filter a fluid body in a well. Relation between a filtration device and its parts. Collection of components of the water pump screen. Relation between a screen and its parts. Collection of linings of the borehole. Relation between a casing and its parts. Material used to filter the fluid in a borehole or well. Size of the particles of the filtration material. Material used in the filtration device. E.g. gravel, pit run, silica sand, washed sand, crushed rock, etc. Component of the well lining where water enters the well. Screen attachment method. E.g. telescoped, on casing, on riser pipe, neoprene (K) packer, Lead packer, etc. Groundwater Data Management Guidelines, Environment Canada, Dec. 1991 Thin outer layer applied to the screen. E.g. galvanized, stainless, copper bearing, low carbon, black, porous, etc. Groundwater Data Management Guidelines, Environment Canada, Dec. 1991. Form of the screen. E.g. slotted casing, perforated casing, bridge slot casing, wire wrap or continuous slot, wire mesh, shutter or louvered, well point, tube, etc. Width of the slots or perforations of the screen. Length of the slots or perforations of the screen. Material that makes up the screen. E.g. metal, steel, iron, copper, brass, bronze, everdur, Armco metal, veriperm, stone, plastic, PVC, ABS, Fibreglass, etc. Internal screen diameter. External screen diameter. Method used for perforating the screen. E.g. drill, grinder, axe / chisel, machine, saw, torch, other, etc. The screen fitting (from the bottom). E.g. bail, open, plug, tail pipe, washdown, etc. Make of the screen. Model of the screen. Screen number corresponds to hole size and is given in 0.001 inch. The value is expressed as an alphanumeric code. Groundwater Data Management Guidelines, Environment Canada, Dec. 1991. Screen placement method. E.g. bail down, pull back, jetted, washed down, etc. Thickness of the screen walls. Collection of materials that prevent undesirable elements from entering the borehole. Method of placing the sealing grouting. Casing left after plugging. Casing slit opposing water bearing zones before plugging. Relation between a seal and its parts. A single part of a well casing. Material in which the casing is made. Can be metal, steel, iron, concrete, wood, brick, plastic, teflon, PVC, ABS, fibre glass, asbestos cement, unknown, other. Groundwater Data Management Guidelines, Environment Canada, Dec. 1991. Coating applied to the casing. E.g. galvanized, stainless, mild, low carbon, copper bearing, black, etc. Groundwater Data Management Guidelines, Environment Canada, Dec. 1991 Form of material used in the casing. E.g. curbing, cribbing, corrugated culvert, hose, etc. Groundwater Data Management Guidelines, Environment Canada, Dec. 1991. Internal diameter of the casing. External diameter of the casing. Thickness of the wall of the casing. Equipment installed in a borehole (like a pump or any other device). General characteristics of the equipment. Type of equipment. Date of installation of the equipment.