Why it is important to estimate the Age of GW?	Modern GW is the biggest resource in the active cycle. Estimating the young GW content in an aquifer helps understand the recharge rates, the residence time and some important dynamics for the GW.
What is the water footprint of humanity?	Of the water consumed: 74% (green) comes from rain recharge 11% is blue, comes from GW/Surface 15% is grey, non-fecal WW (recirculation)
Biggest water consumption?	Production of food: Cereals meat and dairy. --- Most countries "import" water.
Why is modelling and monitoring so important to prevent the consequences of drought?	It helps to identify vulnerabilites, and allow for better adaptation measures, because it helps to predict evapotranspiration and behavior of water bodies and aquifer in drought periods.
How can Particle size distribution serve as an indicator of fecal bacteria?	Foreign (Allochtonous) turbidity coincides with elevated fecal bacteria presence. Because of bacteria adherence to surfaces. Increase of finer particles means foreign turbidity and should be used within the criteria for water rejection after a rain event.
Explain the behavior of GW in barrier islands.	GW is vulnerable, older water tend to accumulate at the limits with seawater, younger water is closer to recharge areas. But, Climate change alters the behavior and the isotropic and chemical composition.
Name 5 risks from to water ressources from Fracturing?	1-Contamination of aquifers with gases 2-Conatmination of surface and GW with spills 3-Accumulation of toxic and radioactive elements in soils 4- overextraction of water resources for the fracking But-"direct"contamination remains controversial
Importance of Deep understanding deep GW in Germany	It is important to plant nuclear disposal sites. To have certainties about the dynamics in the aquifers it is important to characterize this deep-lying aquifers. As well as to plan possible sytes to harvest geothermal energy, or to store Co2, or to extract water avointing contaminated shallow aquifers.
About the Fluvio Lacustrine Environment in March...	Curiosity discovered fine-gainde sedimentary rocks in March. Typical rocks that form in presence of water. The sediment analysis suggest the lake had good chemical characteristics that could have supported life.... but it didn't last long
Use of Gd as a tracer	Good tracers, because of well known temporal behavior.... (weekdays a lot, weekends downs) It ocurse tranciently, and the peaks can be used to derive GW transit times.
Fiber-Optic temperature sensing tech	USing the relation between density, temperature and transmiting capacity of optic fibers, cables that are already installed at lake bottoms can be used to keep track of the mtemperature. Used in lake bottoms, first order streams, and air-water interface.
Residence time and reservoirs of water	Oceans 97% up to 4000 a Glaciers 2% 1000 a Subsurface 0,6% 10000 years lakes <0.1% 10yrs salty lakes <0.1 Air <0.001 10 days Rivers 2 weeks
How to measure Precipitation	Rain Gauge/ Colecting vessel (Helmann) Errors: wind, evaporation With a satellite
How to measure ET	Directly: Class-A-Pan Indirectly: Lysimeter (weight) Empirical with climate data (ETP de Thornthwaite)
Runoff	Discharge gauge in rivers
General balance equation of a system	I=O+dS/dt (Input = output + delta storage)
Water cycle eq	P = ET + Qdischarge + DeltaS
Types of precipitation	Falling (Condensation) Liquid: Mist Rain Solid: Snw Hail
Definiton of wet and Dry year	Wet: Year in which the height of precipitation exceeds the mean value by at least the standard deviation
How to "Regionalise the precipitation"	Using Thiessen Polygons (Drawing contour lines around a precipitation measurements and weghting the rate of precipitation by area) But: doesn't work for areas with strong relief Using Isohyet isohieta es una isolínea que une los puntos en un plano cartográfico que presentan la misma precipitación en la unidad de tiempo considerada.
Possibilities for determination of natural recharge:	Water balance (runoff) Soil water balance Data from water works GW discharge Runoff in receiving streams With tracers Lysimeter
Runoff process
Types of runoff (and where do they appear)	Surface runoff (surface) Interflow (unsaturated soil) GW- Runoff (water saturated ground)
Interflow	Part of the runoff which flows to the receiving stream as a reaction to a trigger event it is slower with respect to surface runoff
Total runoff (Q)	QD direct runoff (surface runoff + interflow) + Qb baseflow (
Composition of a hydrograph	.
Effluent and influent conditions	Effluent: Water infiltrates, river level above water table Influent: Water effiltrates to the river, river level below water table
What is the Mo MNQ method What is the Kille method?	Methos for statistical analysis of water discharge using long-term data
Maillet method, what is it used for? and Forumla	For recession analysis (decline of discharge in the absence of input) Qt = Qo e^-alphaDt Qt= discharge at the time t after the recession started Qo= discharge at beggining alpha: coefficient of discharge alpha= Qt/Vt (Discharge at time t / Sorage at time t) Qo = discharge
Discharge measurement. Methods?	-Weir (presa) measurement -Salt dilution method -Vessel measurement -Determination of flow velocity (hidrología) - Level measusrement
Evaporation depends on 4 factors:	-Difference between vapor pressure at the surface and vapor pressure of air nea the surface - Energy which is available at the surface - Amount of vapor removed with air Amount of water available
ET=	Interception (retention by plants) Evaporation Transpiration
% of ev interception and transpiration in ET	Green land 15 ET 25 Inter 60 Transpiration
What is porosity?	The available amount of empty space en a sediment (the total volume of cleavages (hendiduras) n= Vp/Vg
effective porosity	ne = Vp (that is crontributing to gw movement)/Vs
Usual values of porosity	Sandstone 5-35% Karst 30-50%
Effective porosity by sediment	clay < 5% fine sand 10-20 medium 12-25 coarse 15-30 fine gravel 15-25
Isohypse (isohipsa)	Una isohipsa es en meteorología una línea de igual altitud de geopotencial sobre una superficie dada
Hoy is a isohypse map constructed?	With hydrological triangles, around water head measurement points.
Hydraulic level	(aka Gauge level) gives the potential energy with the dimension of water on each location of the flow net. It depends of elevation energy and pressure
Groundwater potential analysis can be used for	flow direction, general picture identify recharge and discharge zones hydraulic conectivity sea intrution areas
Important information every hydrogeologist need?	-GW flow velocity - Contaminant transport velocity - How much water can be pumped from a well - dropdown ------ for it only h is needed!!
What is the relation between groundwater flow rate and groundwater level?	• Q is directly proportional to the flow through an area (A) • Q is inversely proportional to the flow length (l) • Q is directly proportional to the pressure gradient (Δh) • additionally there is a rock specific proportionality factor: kf , the hydraulic conductivity
Typical Kf values....	Gravel 10-2 Sand, core 10-3 Sand 10-4 Sand, fine 10-5 Clay 10-8
What is permeability?	permeability K is a rock specific measure for the permeability for fluids and gases. It has the unit [m²] and is a measure as the resistance, that the porous medium (and not the fluid itself) opposes to the movement of the fluid. The higher the permeability, the lower is the flow resistance!
Factors affecting hydraulic conductivity?	permeability density and viscosity of water
The flow assumed in darcy is....	linear!!! for turbulent flows>> reynolds number
hydraulic gradient in unconfined aquifer's formula?	Depuit: i= h1^2-h2^2/2l
Horizontal and vertical hydraulic conductivity	Generally the vertical hydraulic conductivity is smaller than the horizontal hydraulic conductivity due to layering
What is transmissivity?	it gives the volumetric flow rate through a cross sectionf of the aquifer which is perpendicular to the flow direction. CS is 1m wide and comprises the whole thickness
Storativity	Capacity of containing water
Storativity in a confined aquifer represents:	The water released from descompression of water and from descrompression of matrix
Storativity in an unconfined aquifer represents:	The drainable porosity: water volume released by gravity by crearing out of the pores!
What is the use of a pumping test?	Determination of hydrogeologic parameters of the aquifer! – Transmissivity – Storativity
Name types of pumping tests:	- Drawdown area (Area in which drawdonw of the table is observed) - Extraction area Part of the drawdown area from which water flows to the well - Extraction width Distance between intersections of the border of the subsurface catchment
Hydrogeologic Pumping test (T,S) how much time needed?	3 days to 4 weeks!
Flow regimes....	Transient: hydraulic head changes with time Steady state: hydraulic head is consant
Preparation of a pumping test	Hydrogeological maps, geological maps • Monitoring network (observation wells) • Water level before pumping test (if available historic water tables) • Composition of groundwater • Lateral extension and thickness of the aquifer • Determination of boundary conditions (afflux, boundaries, leakages  influence on cone of depression) • Administrative preparation, application at the responsible water authorities • Country specific water laws
Requirements on an aquifer and pumping well:	- Aquifer extension indefinite aquifer homogenic, isotropic - thickness constant - pumping test is carried out with constant pumping rate no influx/outflux - the well is complete
Formula for pumping test-confined	Thiem: Q=k * i * A h2-h1= Q/ 2piT * ln(r2/r1)
Formula, unconfined pumping test	Dupuit thiem: Q = 2 pi r h kf dh/dr h2^2-h1^2= Q/ pi kf * ln (r2/l1)
3 stages of a pumping test	I starting regime II transient conditions III steady state
Pumping test: transient flow formula:	Theis + Cooper&Jacob Theis: Curve procedure cooper Jacob: T 2,3Q/S pi Ds
What is an slug and bail test?	method for a single well which is carried out in a piezometer or small-diameter monitoring well (Standrohr). A displacer (Verdrängungskörper) is released into the well  hydraulic head rises
Application of slug – and bail tests vs Pumping tests	Brownfield sites (no extraction of contaminated water) •Short duration of the test compared to pumping test •Lower costs •Lower material effort

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