Groundwater Flow to Wells

Question 1

water wells are used for extraction of water to fill ___, ____, ____, and ____ needs

Answer 1

domestic, industrial, municipal, and irrigation

Question 2

an alternative way of collecting water through manual operation to move groundwater from the aquifer up to the surface

Answer 2

jetmatic pump

Question 3

wells also function to ____ into the ground

Answer 3

inject fluids

Question 4

example of how wells function to inject fluids

Answer 4

injection of hazardous material, provided that there is an impermeable layer

Question 5

as means of groundwater management, wells sometimes use ______ at rates greater than natural recharge

Answer 5

artificially recharge aquifers

Question 6

during well pumpage, ____ of the head in the aquifer around the well occurs

Answer 6

drawdown

Question 7

during ____, there is increase in the head of the aquifer

Answer 7

injection

Question 8

what is a drawdonw?

Answer 8

a change in the hydraulic head of an aquifer around a well due to pumping as part of an aquifer test or well test

Question 9

is the change in the hydraulic head observed at a well in an aquifer, typically due to pumping a well as part of an aquifer test or well test

Answer 9

drawdown

Question 10

a pumping cone, or ____, will form in the aquifer around a ______ as the water level _____

Answer 10

cone of depression
pumping well
declines

Question 11

in _____, the head is constant with time, no cone of depression

Answer 11

steady state flow

Question 12

in this flow regime, flow is in the horizontal radial direction

Answer 12

radial flow

Question 13

direction of the flow in radial flow

Answer 13

horizontal radial direction

Question 14

radial flow exist in the time period before the _____ has reached the _____ of the reservoir, also known as _____ period

Answer 14

pressure transient
boundaries
infinite-acting time period

Question 15

t or f: radial flow is often observed following other flow regimes

Answer 15

T

Question 16

emergence of radial flow in an infinite conductivity hydraulically fractured well

Answer 16

linear-fracture flow to radial flow

Question 17

1 cubic feet is equal to how how many gal

Answer 17

7.48

Question 18

how many minutes in 1 day

Answer 18

1440

Question 19

discharge causes decline in the cone of depression, or ____

Answer 19

drawdown

Question 20

recharge causes _____ of the cone of deppression

Answer 20

buildup

Question 21

t or f: cone of depression declines as hydraulic head decreases during pumpage

Answer 21

T

Question 22

t or f: even if the cones of depression of nearby wells are already intersecting, you can still extract groundwater

Answer 22

f (you can not)

Question 23

the distance from the land surface (or the measuring point) to the water in the well under non-pumping (static) conditions

Answer 23

static water level

Question 24

how is an aquifer test done?

Answer 24

done by constantly stimulating the aquifer through constant pumping and observing the aquifer’s “response” (drawdown) in observation wells

Question 25

aquifer test is a common tool that hydrogeologist use to characterize a system of ____, _____, and ____

Answer 25

system of aquifers, aquitards, and flow system boundaries

Question 26

is a particular type of aquifer test where water is quickly added or removed from a groundwater well, and the change in hydraulic head is monitored through time, to determine near well aquifer characteristics

Answer 26

Slug test

Question 27

slug test is also known as

Answer 27

bail-down test

Question 28

a cylinder that is heavier than the water, which causes displacement of water equal to its volume when dropped into the well

Answer 28

slug

Question 29

explain the slug test

Answer 29

1. a slug is dropped into a well which cause water in an equal volume of the slug to be displaced 2. the water head rises, causing the flow to increase, and eventually water level slowly drops 3. water level eventually reaches the head of the aquifer, the rate of dropping of water level decreases because of the decline in gradient 4. water level reaches initial head, slug is taken out, water level becomes so low 5. well is recharged again as water from the aquifer flows into the well again

Question 30

initiated by rapidly lowering the water level in the control well and then taking measurements of the rising water level in the well, slug is withdrawn

Answer 30

rising-head test

Question 31

rising-head test is also known as

Answer 31

slug-out test

Question 32

is conducted by rapidly raising the water level in the control well and subsequently measuring the falling water level.

Answer 32

falling-head test

Question 33

falling-head test is also known as

Answer 33

slug-in test

Question 34

boundaries are considered to be either ____ or ____

Answer 34

recharge or barrier boundaries

Question 35

is a region in which aquifer is replenished

Answer 35

recharge boundary

Question 36

is an edge of the aquifer, where it terminates by either thinning, abutting a low permeability formation, or has been eroded away

Answer 36

barrier boundary

Question 37

much of water sources in the philippines is dependent on

Answer 37

surface water

Question 38

artificially recharge aquifers is the artificial injection of

Answer 38

surface water

Question 39

one example of injection of fluids into the well

Answer 39

storing hazardous material, must have impermeable confining layer

Question 40

an inverted cone is created in the head of the aquifer during

Answer 40

injection

Question 41

how is water pumped up with oil and returned to the ground

Answer 41

1. oil and water pumped up together into oil wells 2. separators separate oil from water, sand, and other naturally occurring materials 3. produced water with oil removed is injected back onto the geologic zone from which it oroginated

Question 42

t or f: steady state flow still creates cone of depression

Answer 42

F (it doesn't)

Question 43

radial flow is created by _____ which results in _____ pressure

Answer 43

pumping out of water negative

Question 44

1 cubic feet is equal to how many cubic meter

Answer 44

0.028

Question 45

1 gal is equal to how many cubic meter

Answer 45

0.0045

Question 46

aquifer tests determine what

Answer 46

near surface aquifer characteristics

Question 47

how many hours should a pumping test be conducted

Answer 47

24-48 hours

Question 48

t or f : if the rate of the pumping test is constant, the aquifer is sustainable. if there is changes, it may not sustain

Answer 48

T

Question 49

a slug test is a particular type of aquifer test where groundwater is being quickly _____ or ____

Answer 49

added or removed

Question 50

two types of barrier boundary

Answer 50

bounded by stream on one side bounded by an impermeable boundary on one side

Question 51

what is perennial stream

Answer 51

have water all year round

Question 52

what is intermittent stream

Answer 52

water is dependent on groundwater baseflow

Question 53

what is ephemeral stream

Answer 53

water during/after precipitation

Question 54

t or f: it is difficult to delineate boundary through ocular investigation

Answer 54

T

Question 55

t or f: aquifer thickness should be very large compared to resultant drawdown near real well

Answer 55

T

Question 56

delineating hydrogeologic boundaries needs ______ and _____ methods

Answer 56

geophysical and dating