Table of Contents | Groundwater Intro

Basics

Start/overview - Subsurface water; interested parties; flow of groundwater; rain entering the ground; groundwater chemistry; ground settlement.

DRCY
Darcy's law - Pressures in (ground)water; law of Darcy and examples; pressure and hydraulic head; inertia in groundwater flow; head measurement; anisotropy; velocity of groundwater particles.

SYST

Groundwater systems - Flow lines; groundwater systems; aquifers and aquitards; aquifer types; Dupuit simplification of aquifers; flow in aquitards; stacked aquifers.

FLOA
Flow principles A - Flow in a small element; equation of movement; assembly of elements; isohypses and flowlines; Dupuit aquifer schematisation; radial symmetrical flow; shape and size of flow domain; anisotropic permeability; superposition.

FLOB
Flow principles B - Boundaries of a flow domain; symmetrical flow; transient flow and storage; water balance; lysimeter; statistical methods.

LEGA
Groundwater legislation - Environmental legislation; groundwater abstraction; altered open water level; pollutants.

Land surface

RAIN
Precipitation - Precipitation and infiltration; amounts and variability; distribution in time; empirical intensity relation; drought; rain gauge.

NSAT
Unsaturated groundwater - Water pressure and moisture content; pF-curve; unsaturated flow; stationary profile; unsaturated permeability; flow calculation; steady vertical flow; storage coefficient.

EVAP
Evaporation - Evapotranspiration; solar radiation; net radiation; evaporation of a wet surface; sensible and latent heat; equilibrium and atmospheric evaporation; evaporation of a vegetated surface; reference evapotranspiration; actual evapotranspiration; measurement of evapotranspiration.

VEGE
Crop growth - Photosynthesis; organic matter production; production and evapotranspiration; reference- and potential evapotranspiration; actual evapotranspiration; crop- and reduction factors; soil moisture and groundwater table; critical suction depth; remote sensing; natural vegetation.

Flow

NUMA
Numerical flow calculation A - Finite difference elements; hydraulic head calculated in spreadsheet cell; fixed head boundary; abstraction; increasing an abstraction; instability.

NUMB
Numerical flow calculation B - No-flow boundary; stacked aquifers; abstraction only in upper aquifer; reduced aquitard resistance; flow over boundaries; sensitivity analysis; model calibration.

OPEN
Interaction with open water - Constant open water level?; drainage relations; bottom resistance; drainage by a diffuse drainage resistance; variable drainage resistance; freely outflowing drainage.

ANLA
Analytical flow calculation A - Analytical vs. numerical calculation; discharge of rain in a Dupuit aquifer; discharge with parallel ditches; different ditch levels; linear differential equation and superposition.

ANLB
Analytical flow calculation B - Radial-symmetrical flow; rain on a circular island; abstraction in the centre of a circular island; pumping tests; Forchheimer approximation for phreatic aquifers; semi-confined flow.

ANLC
Analytical flow calculation C - Transient (time-dependent) flow; transient flow towards a well; method of mirror-images; partially penetrating well; approximation of Logan; abstraction in a 3-D soil mass.

SALT
Salt groundwater - Heavier salt water; fresh and salt water; Badon/Ghijben/Herzberg simplification; confined aquifer near the sea; strip surrounded by sea; upconing of salt water.

DSCH
Discharge of precipitation - River basin and Unit Hydrograph; linear reservoir; linear reservoir vs. realistic IUH; determination of reservoir coefficient; Rational Method; basic equation of rain discharge.

Chemistry

SOLU
Soluble compounds - Complex groundwater chemistry; properties of rainwater; interaction between rain water and soil; properties of sea water; pollutants and special circumstances; macro-ions; ion-balance; pH; speciation; electrical conductivity EC.

CARB
Calcium and carbon dioxide - Calcium, magnesium and hardness; inorganic carbon; dissolution of calcite; precipitation of calcite; CO2-production in rootzone.

RDOX
Redox reactions - Exchange of electrons; redox potential; pH/Eh-diagram; organic matter; sequence of redox processes; nitrate and phosphate; pathogenic organisms.

IOEX
Ion exchange - Adsorption and desorption; adsorption competition; selectivity coefficient; ion exchange; adsorption capacity; distribution of ions; inflow of foreign water.

SORB
Sorption of pollutants - Distribution coefficient; organic compounds; cations of heavy metals; anions of metals and metalloids.

DISP
Groundwater displacements - Irregularity of displacements; movement of plane front; movement towards abstraction; size of intake area; abstraction in permanent flow; injection in permanent flow; dispersion; diffusion vs. dispersion; dispersivity values; solute transport; retardation of solute.

Measurements

RCNA
Groundwater reconnaissance A - Scanty subsoil information; permeability and chemical properties; geophysics vs. borings; remote sensing; types of geophysical measurements; borehole logging; vertical electrical sounding VES; VES interpretation; profiling.

RCNB
Groundwater reconnaissance B - Electromagnetic sounding; refraction seismography; seismic determination of bedrock.

BORE
Exploration drilling - Sequence of investigations; implementation of drilling; drilling in rock; soil and water sampling; borehole with piezometers; soundings; determining permeability; permeability and flow calculations.

PIEZ
Piezometers - Construction of piezometers; installation of piezometers; sounding a piezometer; sampling water; piezometer records.

Technics

WELA
Abstraction wells A - Purpose of wells; dug wells; drilled wells, screen and gravel pack; positioning of screens; maximum abstraction; wells in rock; temporary wells.

WELB
Abstraction wells B - Well drilling; drilling with casing; drilling with drilling mud; borehole logging; well completion.

WELC
Abstraction wells C - Well monitoring; clogging by iron; clogging by organic compounds; clogging by soil particles; remediation of clogging; injection wells; contract specifications; abstraction of spring water.

POLL
Remediation of pollution
Remediation of pollution; actual location of pollutant; historical explanation; remediation techniques; in situ remediation; abstraction of polluted groundwater; hydrological screen; desorbing reagents; insoluble liquid pollutants, LNAPL and DNAPL.

DRAI
Drainage and infiltration - High groundwater level; drainage by ditches; sub-surface drains; level-controlled drainage, vertical drainage, maintenance; irrigation.

SETL
Ground settlement - Geo-technics; vertical deformation; vertical soil pressure; elastic material; Terzaghi's law of soil compression; void ratio; unloading and reloading; value of compression index; thin layers; saturated soil; soil and water pressure; decrease of water pressure; consolidation.