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Appendix A

Handpump/Drilling Glossary line

ADSORPTION - The process whereby small particles (e.g. clay) attract and hold ionic constituents.

AESTHETIC - Refers to those aspects of drinking water quality that are perceivable by the senses, namely taste, odour, colour and clarity.

ANCHOR BOLTS - Screws welded into a frame or plate or are grouted directly into the cement pad. They are used to attach the pump to the pad.

ANNULAR SPACE ("annulus") - the space between the well casing and the borehole wall.

ARTESIAN AQUIFER - See Confined Aquifer.

AQUIFER - A saturated geological unit (eg. sands, gravels, fractured rock) which can yield water to wells at a sufficient rate to support a well.

AQUITARD ("aquiclude") - Geological formations or strata that have the ability to store water but can only transmit water in very small quantities (eg. silt, siltstone).

ATTENUATION - The reduction that occurs in contaminant concentrations during transport through soil or rock.

BEARINGS ("fulcrum") - Pivot points used in all lever action handpumps to connect handles to the pump head.

BIODEGRADATION - The breakdown of putrescible (organic) material by biological processes.

BOREHOLE - A hole drilled, bored or dug into the ground into which a well casing is placed.

BOBBINS - Rubber stoper used as a one-way valve in some plunger assemblies and foot valves.

CENTRALIZERS - Devices used to ensure that the pump rod moves straight up and down within the rising main. Can also be installed to ensure the well casing is installed within the center of the borehole

CHEMICAL PRECIPITATION - Contaminant removal from solution through the chemical combining of anion and cations to form solids.

CAPTURE ZONE - The area of water table/piezometric surface drawdown created by pumping a well.

CONE OF DEPRESSION - Cone of depression (or "influence") is the draw-down of the water table or potentiometric surface that happens when a well is pumped. The drawdown cones of two wells close together may overlap so that if the wells are pumped simultaneously they will compete with each other for available groundwater (well interference).


CONE OF INFLUENCE - The cone of influence is the depression in the water table or potentiometric surface that is produced when a well is pumped. The cones of influence of two wells close together may overlap so that if the wells are pumped simultaneously they will compete with each other for available groundwater (well interference).

CONFINED AQUIFER - A confined aquifer is a fully saturated aquifer whose upper and lower boundaries are impervious geologic units. Water is held under pressure and the water level in wells stands above the top of the aquifer. Completely impervious layers rarely exist in nature and hence truly confined aquifers are relatively rare.

CONSERVATIVE POLLUTANT - A pollutant that is relatively persistent and resistant to degradation, such as PCB and most chlorinated hydrocarbon insecticides.

CONTAMINATION - The introduction of materials which makes otherwise potable water unfit or less acceptable for use.

CUP LEATHERS - Seals used to create suction and pull water up the rising main when the plunger is moved up. Most pumps used curved "cup" leather seals, but some rely on leather or nitrile rubber rings.

CYLINDER - Down hole device used to push water up out of the ground. Key parts are: Cylinder, Plunger Assembly, Cage, Valve, Bobbin, Cup leathers, End Caps & Seals, Foot Valve

CYLINDER BARREL - The cylinder body or housing in which the plunger moves.

DEVELOPMENT - The act of pumping and surging water in a well to remove mud and dirt from within the filter pack, borehole wall and local aquifer. When done completely, pumped water will be free of suspended material. Wells must be developed after drilling to ensure that the cylinder is not prematurely worn-out by the abrasive action of suspended material moving between the plunger and cylinder walls.

DIFFUSION - The spreading of ions into a fluid or porous medium in a direction tending to equalize concentrations in all parts of the system; it is understood to occur in the absence of fluid convection and as a result of the thermal kinetic energy of the particles.

DILUTION - Usually refers to the mixing of contaminated water through mechanical dispersion and molecular diffusion (due to chemical gradients).

DIRECT ACTION - Type of handpump which has non-levered Tee-handles directly connected to the pump rod.

DISCHARGE AREA - The zone in which groundwater leaves the ground either as a spring or into a water body.

DISPERSION - The movement of dissolved solids in the water by chemical forces which results in lower dissolved-solid concentrations.

DRAWDOWN - Drawdown is a measure of the amount of lowering of the water level in a well when pumping is in progress.

DROP PIPE - slang term - see "Rising Main".

EFFECTIVE HYDRAULIC DIAMETER - The area in which water from the aquifer can move freely into a well. If a borehole is completed with a well casing plus surrounded by a filter pack material, the effective hydraulic diameter is equal to the diameter of the borehole.

EVAPOTRANSPIRATION - A combination of evaporation from open bodies of water, evaporation from soil surfaces, and transpiration from the soil by plants.

FILTER PACK - A filter pack is coarse sand or fine gravel (2-6 mm diameter) that is placed between the borehole wall and screen. Filter packs are used to settle-out fine grained particles that may otherwise enter the well.

FISHING - The act of trying to retreive a tool or pump part dropped down into a well. It also is the name for the tool used to extract foot valves from open top cylinders.

FLOWING WELL - A well in which the static water level is above ground level.

FOOT VALVE - Part of the cylinder that holds the column of water in the rising main while the plunger is being pushed down after each up-stroke.

FOUNTAIN - Term used in many French speaking countries to describe the above-ground pump assembly.

FRACTURE - A general term for any break in a rock attributable to tectonic forces, magma movement, thermal processes; glacial or erosional loading or unloading, and earth tides. (Exact causes of fractures are not always known.) They occur in all types of rocks. Incomplete fractures are cracks; a fault is a fracture zone along which movement occurs. Fractured-rock aquifers often have a fast, turbulent flow; are less isotropic and less homogeneous than porous media, and Darcy's law may not apply to them. Hydrogeologic investigations in fractured rock are usually either discrete studies (based on the careful measurement of each fracture) or continuum studies (which investigate the properties of large regions of the fractured material).

GNEISS - A hard, coarse-grained, foliated (banded), metamorphic rock (altered by great temperature and/or pressure) of quartz, feldspar and mica; often has low water yield.

GROUNDWATER - Water that occurs in the subsurface below the water table.

GROUNDWATER FLOW SYSTEM - The total system which describes the movement of water in the subsurface from the point where it enters the ground to where it leaves. Water moves in the direction of decreasing pressure that may be upward in some localities.

GROUNDWATER UNDER THE DIRECT INFLUENCE OF SURFACE WATER (GUDI) - Groundwater having incomplete/undependable natural subsurface filtration of infiltrating surface water. It may contain surficial contaminants like E.coli, giardia and cryptosporidium not found in secure groundwater supplies.

GROUNDWATER VULNERABILITY - The sensitivity of a groundwater system to human and/or natural water quality impacts.

GROUT - A sealing material of cement or bentonite (swelling clay) used to create a sanitary seal in the annular space above the filter pack to prevent surficial contaminants from entering the well.

HANDLE ("lever") - Lever that connects the pump rod to the pump head. Often includes some mechanism to add counterweights to balance the weight of the water being lifted up the rising main.

HANDPUMP - A water pump powered by the movement of people's arms or legs.

HYDRAULIC CONDUCTIVITY -The ability of subsurface materials (sand, rock etc.) to allow a fluid (ie water) to flow through it.

HYDRAULIC GRADIENT - The change in hydraulic head (pressure) per unit distance in a given direction (dimensionless). It is the driving force of fluid flow in a porous medium.

HYDROGEOLOGY - The subject dealing with the occurrence, characterization and movement of water below the earth's surface.

HYDROLOGICAL CYCLE - The continuous circulation of moisture and water on earth. The amount of water never changes but its state and position in the cycle does change.

IMPERMEABLE - Resistant to flow of or penetration by water or other liquids.

ION EXCHANGE - See adsorption.

KARST - A carbonate rock terrain where fractures have been enlarged by chemical solution or physical erosion.

LEACHATE - The liquid that results from the process of water, derived from precipitation, streams and/or groundwater leaching through sanitary landfills or dumps.

MAINTENANCE: Work proactively done to prevent unexpected pump breakdown.

MILLIGRAMS PER LITRE (mg/L) - A unit of measure expressing the concentration of a substance in a solution. Is equivalent to parts per million (ppm).

NON-CONSERVATIVE POLLUTANT - Quickly degrade and lack persistence, such as most organophosphate insecticides.

NON-POINT SOURCE - An area from which pollutants are exported in a manner not compatible with practical means of pollutant removal (e.g. crop lands.)

OBSERVATION WELL - A well drilled solely for the purpose of monitoring a potential or an existing source of contamination.

OPEN TOP CYLINDER - Cylinder has no constricted top cap. When installed with a large diameter rising main, the pump rod and plunger assembly can be pulled-out without removing the rising main. The foot valve is designed to be pulled up through the cylinder body rather than being removed through the bottom of the cylinder.

OUTLET - The term used to describe the spout assembly of some pumps.

OVERBURDEN - Unconsolidated (loose) soil overlying rock.

PERMEABILITY - The ability of an aquifer or water-bearing formation to allow water to pass through it. Permeability is also known as effective porosity because it is a function of interconnected saturated pore spaces.

PERMEABLE - Permitting the flow of water or other liquids.

PHREATIC ZONE - See saturated zone.

PIEZOMETER - A device for measuring pore water pressure (i.e. measuring the location of the water table). Some types of piezometers can also be used for collecting water samples. As a result, wells designed specifically for collecting water samples are often referred to, incorrectly, as piezometers.

PIEZOMETRIC SURFACE - The water level surface that can be defined from the mapping of water level elevations in wells tapping into a confined aquifer.

PISTON - Slang term - see "plunger".

PLUNGER ASSEMBLY ("piston")- The part of the cylinder that is connected to the pump rod and which forces water up the rising main.

POROSITY - The ratio of the volume of voids to the total volume of a rock or unconsolidated material. It is a measure of the amount of empty 'space' in a material. See permeability.

POSITIVE DISPLACEMENT - Downhole cylinders pushing (displacing) water up the rising main.

POTABLE WATER - Water fit for human consumption.

PUMP HEAD - Pump assembly attached to the stand. Contains the following parts: Surge chamber, Handle, Bearings, Outlet Assembly.

PUMP ROD ("plunger rod", "sucker rod", "connector rod") - Steel rod that connects the pump handle to the plunger assembly within the cylinder. It is usually threaded and coupled to allow it to be easily taken apart when extracting the plunder assembly to change the cup leathers.

PUMPING LEVEL - The level at which water stands in a well when pumping is in progress.

PUMPING LIFT - The maximum height of the water column that can be pushed up the rising main.

PUMP STAND ("pump base" or "pedestal") - A base that attaches the handpump to the ground and connects to the rising main.

RAW WATER - Surface or groundwater that is available as a source of drinking water but has not received any treatment.

RECHARGE AREA - The part of a flow system where precipitation percolates downward.

RINGS - Some pump cylinders rely on leather or nitrile rubber rings instead of cup leathers to create suction within the cylinder when the plunger is moved up.

RISING MAIN("drop pipe", "draw pipe", "pump column") - The pipe connecting the pump cylinder to the pump body. Water moves up this pipe and out the pump spout during pumping when the plunger is moved up and down within the cylinder.

SATURATED ZONE - The zone below and including the water table in which all pore spaces or fissures are totally filled with water. Also referred to as the phreatic zone.

SEMI-CONFINED AQUIFER - A semi-confined (leaky) aquifer is a completely saturated aquifer overlain by a semi-impervious layer and underlain by a impervious layer. Lowering of the potentiometric head in a leaky aquifer by pumping will generate a vertical flow of water from the semi-pervious layer into the pumped aquifer.

SORPTION - The attachment of dissolved ions to rock minerals, generally by electromagnetic bonding forces.

SPECIFIC CAPACITY - A measure of pumping rate per unit drawdown. If you know a wells specific capacity, you can estimate drawdown at different pumping rates. For example, the specific capacity of a well that delivers 20 gpm with 40 ft of drawdown would be 0.5 gpm/ft. At 30 gpm the drawdown would be 30/.5 = 60 ft.

STAND PIPE - A device that measures the height of the water table in an unconfined aquifer.

STATIC WATER LEVEL - Static water level is the level at which water stands in a well when the water level is at equilibrium with atmospheric pressures). It is a measure of the depth from the ground surface or from a known measuring point to the water level.

STORAGE COEFFICIENT - see storativity.

STORATIVITY - The volume of water released from storage per unit surface area of aquifer per unit decline in hydraulic head (dimensionless).

STRATA - Layers of deposited rock, soil etc which are distinguishable from each other.

STROKE - The maximum distance that the plunger moves when the handle is moved.

SUBMERGENCE - Vertical distance between pumping level and pump intake.

SUCKER ROD - Slang term - see "pump rod"

SUCTION - Pumps without down-hole cylinders rely on suction generated by above-ground cylinders to lift water up the rising main.

SURFACE WATER - Water bodies (lakes, wetlands, ponds - including dugouts), water courses (rivers, streams, drainage ditches), infiltration trenches and areas of temporary precipitation ponding.

SURGE CHAMBER ("water tank" or "delivery cup") - Connects the rising main to the outlet assembly. It usually has a larger diameter than the rising main. The water level in surge chambers rises and falls with each pump stroke, but the spout inlet stays submerged. This evens the flow of water between pump strokes.

TAIL PIPE - Extension pipe screwed into the bottom of a cylinder to increase submergence.

TRANSMISSIVITY - The rate at which groundwater can flow through an aquifer section of unit width under a unit hydraulic gradient. It is the average permeability of a section of the entire aquifer at a given location multiplied by the thickness of the formation.

UNCONFINED AQUIFER - An aquifer whose upper boundary is defined by the water table (water is at atmospheric pressure). Water usually saturates only part of the geologic unit and there is no upper confining layer. Also called a "water table aquifer".

UNSATURATED ZONE - The zone above the water table in which soil pores or fissures are less than totally saturated. It is also called the vadose zone or the zone or aeration.

VADOSE ZONE - See unsaturated zone.

VALVE - A device that allows water to move in only one direction. A valve at the bottom of each cylinder holds the column of water in the rising main while the plunger is being pushed down after each up-stroke. A one-way valve in the plunger allows water to flow through the plunger while it is being pushed down.

VENT HOLE ("weeping hole") - A small hole drilled in the rising main below the depthof frost penetration during winter. It is used to prevent frost burst in cold climates.

WATER - A compound of oxygen and hydrogen. Water is commonly found in liquif form, but below freezing (0 degrees C) it forms a solid and above 100 degrees C it forms a vapour (steam). In pure form it is colourless, odourless and tasteless, but usually contains disolved compounds that give drinking water sources their unique taste, appearance and odour.

WATER TABLE - The top of the zone in which all pore spaces or fissures are totally filled with water.

WATER TABLE AQUIFER - See Unconfined Aquifer.

WELL - A hole drilled or dug into the ground to extract liquid. Drinking water wells must be deep enough to reach far below the water table or they may have no water during the dry season when the large of recharge causes the water table to fall.

WELLHEAD PROTECTION - The pro-active management of land to assess and mitigate potential risks posed to well water quality.

WORKING BARREL - Slang term - see "open top cylinder".

YIELD - The amount of water that is produced when a pump is operated for a fixed number of full strokes.


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