GROUNDWATER FLOWS TO WELLS Flashcards
maximum rate of pumpage that can be allowed while ensuring that water-level declines are kept with acceptable limits.
Groundwater yield
maximum pumping rate that can be supplied by a well without lowering the water level in the well below the pump intake
Well yield
maximum rate of withdrawal that can be sustained by an aquifer without causing an unacceptable decline in the hydraulic head in the aquifer
Aquifer yield
maximum rate of withdrawal that can be sustained by the complete hydrogeologic system in a groundwater basin without causing unacceptable declines in hydraulic head in the system or causing unacceptable changes to any other component of the hydrologic cycle in the basin.
Basin yield
is the artificial application of water to soil or land to assist in the growth of crops and vegetation, typically to supplement insufficient rainfall and ensure optimal agricultural productivity.
Irrigation
is the process of removing or lowering the water table in soil or construction areas through pumping or other techniques, typically to create a dry and stable environment for construction, mining, or excavation activities.
Dewatering
a model refers to the process of defining and assigning specific values to the parameters within a mathematical or computational model.
Parameterizing
who said that groundwater science is like trying to read a textbook with a hole punch…”
D. Irvine
K and transmissivity properties can be determined from single well tests
At least one pumping well…
To determine storage properties
At least one observation well
Better estimates of storage and transmissivity
Boundaries
Anisotropy
Multiple observation wells
-record the pump rate and know the location of the pumping
well, and observation wells
From the test
Solved transient flow (accounting for storage) to a well in an infinitely extending aquifer
Theis Solution
affects the slope of the time drawdown curve
Transmissivity
Higher transmissivity,
lower slope
Higher transmissivity requires a __________ to move the same Q
lower gradient
affects the lag time for drawdown to commence
Storativity
Higher storativity,
longer lag time
means that more water is available in storage, which buffers drawdown (initially)
Higher storage
What properties affect drawdown in an unconfined aquifer?
Storativity
Horizontal conductivity
Vertical conductivity
Specific yield
three phases of unconfined drawdown
neuman solution
drawdown is controlled by the specific yield of the aquifer called
the concept of delayed yield
refers to the decline of water level of well due to pumping
draw down
it refers to the vertical distance from the ground surface to the water level in a well, borehole, or piezometer
Depth to Water
true of false: drawdown is always reported as a positive number
true
is a property of an aquifer that describes its ability to transmit water
Hydraulic conductivity (k)
Generally performed in piezometers
Can’t perform pump tests
Have a significant response to a small stress
slug test
a confined aquifer is bounded on one side by a straight line impermeable boundary
bounded aquifer
