Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Soil and Water > Final :) > Flashcards

Final :) Flashcards

1
Q

What is a piezometer, and why are they used?

A

It is a cheaper, easier alternative to monitoring wells to find the depth to water. They don’t require drilling, normally a 1 or .5 inch diameter. They measure water in the Z value.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the hydraulic head?

A

The sum of the elevation head and the pressure head. The elevation head is the elevation of the bottom of the well above sea level, the pressure head is the elevation of the water table to the bottom of the well.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

when aquifers get saltier, the density___

A

increases, so the water is heavier. As density increases, the pressure head decreases and so does the water table.
Normally deeper water is saltier because it’s had time to collect minerals.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

In order for you to use a 3-point problem you need…

A

a homogeneous aquifer (impossible)
fully saturated
isotropic (water can flow any direction it wants, hard to have in bedrock)
hyd. head doesn’t change over time
no soil/water compression
no unknown boundaries (rivers, clay layers)
laminar/straight flow (never true!)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what is the vadose zone?

A

the unsaturated zone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What’s the equation for elevation head and pressure head?

A

EH- surface elevation - depth to the bottom of the well
PH- depth to the bottom of the well - depth to water

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

How would you collect 3D gw data?

A

Nested piezometers- small baby wells put in the same well hole at different depths so you can tell what the water is doing at each depth

Packer system-

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is a pumping test, and what does it measure?

A

It is when you have 3 wells and you pump the middle one to create a cone of depression, then you measure the drawdown and find the hydraulic conductivity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is a slug test and why are they used instead of a pumping test?

A

A slug test is when you only use one well, it’s used because it’s less expensive & time-consuming than drilling 3 wells. The downside is that you are only measuring the hyd. conductivity of one specific are and guessing that it applies to a larger area. This can be used for short distances and only with unconfined aquifers.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Describe the processes of a slug test

A

Lower the slug into the well and let water level displace and equalize.
Pull the slug out, create a depression and let the water lift and equalize again.
The speed that this happens, will find the conductivity of the aquifer. Calculate the speed of recovery and find where h = 37&

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How and why do pumping wells cause cones of depression?

A

Pumping wells sink down the water table because of pumping rate and conductivity. If you take water out fast, and the conductivity is low there will be a cone bc the water can’t replenish fast enough.

SO you dig your wells super deep.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is transmissivity?

A

The amount of water an aquifer can move to a pumping well as it’s pumping.

T=kb, (hyd. conductivity times aquifer thickness)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is storativity?

A

The amount of water released by the aquifer per drop in unit head (unitless)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What equation should you use when it asks for drawdown? What about for a pumping test conductivity? Slug test conductivity?

A

Drawdown- Theis, h0-h=(Q/4rpi)…
Pumping test- Tiem, unconfined- K=(Q/pi(b2-b1)…
confined- T=Q/2pi(h2-h1)…
Slug test:Horslev, K= r^2*ln(Le/R)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the classifications of the TDS (total dissolved solids)

A

In thousands
0-1 fresh
1-10 brackish
10-100 saline
above this is brine, uncommon

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the most common dissolved solids?

A

Ca, Mg, Na, K, Cl, So4, HCO3, CO3

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What are the EPA classifications for water quality?

A

Class 1- special water, water currently in use for drinking, ecological use, irrigation, etc. Cleanest, most protected like the ogalala aquifer

Class 2- water not currently used but could be in the future. it might not be clean enough to drink but making it drinkable wouldn’t be too expensive. still a little protected

Class 3- water too saline or too polluted to be used for drinking or ecological uses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is the difference between pollution and contamination?

A

Contamination is when an ecosystem can’t be used for its intended purpose.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Whats the most common water pollutant?

A

Microbiological agents
-Bacteria (E.coli)
-Parasites
-Protazoa
-Viruses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What are main classes of gw contaminants?

A

-Heavy metals (Ag,As, Cd, Cr, Pb)
-Organic pollutants (BTEX in gasoline, VOC’s, Pesticides, DDT!!, PCBs in the hudson river)
-Radionucleide (Hampford)
-Nutrients (PO3, NO3)
-Suspended sediments
-Hormones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is a geoprobe?

A

It is a drilling tool used to sample soil and install monitoring wells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is a split spoon sampler?

A

A tube filled with a plastic casing that you push into the ground while drilling and fills with soil.
Gives the info for a boring log, that needs to be detailed.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What are screen intervals and risers

A

A screen interval is a slotted piece of well that allows water to enter. Above this is the riser that does not allow water to enter. A sand pack is installed around the screen interval to prevent clogging & then seal it with bentonite clay to cap the top!

24
Q

What is development of a well?

A

Pumping out the fine sediments or the well, like clay. Repeated until the groundwater is clear. MUST DO

25
Q

What are some issues you have to consider before drilling a well?

A

How deep does the well need to be (what kind of geoprobe can go that far?)
What material are you drilling through (bedrock vs soil)
Will it need to go through buildings?
How large of an area needs to be investigated? (how to transport a geoprobe)
Where are the areas of concern?

26
Q

what is a target analyte?

A

The specific thing you are sampling water for like heavy metals or VOCS

27
Q

If you are sampling heavy metals (lead arsenic mercury) how would you?

A

You would need…
-low flow pump like with a peristaltic pump so you lower turbidity & don’t kick up sediment from the bottom
-a filter to remove particulates
-acidified sampling container to keep metals from precipitating

28
Q

If you are sampling VOC’s, how would you?

A

You would need…
-low flow sampling to lessen volatilization (evaporation)
-Sample collected in a VOA vial with no air
-analysis will occur without taking off the cap

29
Q

What is a QA/QC

A

A type of insurance policy saying you gave the right information & did the right procedure

30
Q

What are examples/ types of QA/QC?

A

Trip blank, state certification by sending a bunch of spiked samples and the lab has to report what’s in it to prove they know their stuff, duplicate samples to make sure they’re the same

31
Q

What is a trip blank?

A

A sample container of water and a little acid and a piece of tape over the cap that proves it was never opened. This shows that the lab equipment isn’t contaminated

32
Q

What might change how the water is represented when tested? And how do we fix it?

A

If there are VOC’s, they may have evaporated
Reduced metals can oxidize
Organics can decompose
ALL after exposure to oxygen. This is why the well is purged! 3 well volumes!

33
Q

What are tools to collect water?

A

a bailer (disposable) , peristaltic pump (low flow, only with water less deep than 32 feet)
bladder pump must decontaminate all pumps!

34
Q

Whats the most common source of groundwater pollution?

A

Leaking underground storage tank, but now they have a double walled design and leak detection systems

35
Q

Why are UST leakages so bad?

A

It separates into 3 sections/ The soluble BTEX dissolves into the water. The nonsoluble part floats on top of the water (pure gasoline), the vapor parts evaporate and go through the ground and into your house above!

36
Q

What are VOC’s used as

A

Cleaners, degreasers, solvents, pesticides. you use low flow sampling for these

37
Q

What are LNAPLs? DNAPLs?

A

light non-aqueous liquids that will float on top of the water & escape detection (gasoline, fuel oil, diesel fuel) screen above the water table

dense non-aquous liquids that sink & hit bedrock then sink into fractures of the bedrock. BIG ISSUE. more expensive, expansive! (tolune, TCE)

38
Q

Heavy metals are normally not a water issue why?

A

They are cationic and strongly retained on the CEC

39
Q

Exceptions to the heavy metal no water rule:

A

ASO, BO3, CrO, MoO, SeO

40
Q

How to fix heavy metals in soil

A

Wash it with ammonium so it shoves the anionic ones off the soil grains or just dig and haul it away

41
Q

Where does nutrient pollution come from?

A

Farms and septic systems, mostly no3- & po43

42
Q

What happens in a leach field?

A

liquids and waste pumped into the field and processed by the natural bacteria

43
Q

What is a phase 1 ESA

A

Tells you what contamination might be present based on historical data & where to look

44
Q

What is the phase 2 ESA

A

Testing, monitoring, checking stuff out for contamination, “confirms the type and extent”

45
Q

What is phase 3 ESA

A

Remediation of a site

46
Q

Most common strategy for treating groundwater:

A

Pump and treat: extract polluted groundwater & pass it through a treatment system. then it could go to a surface water body so that it could become oxygenated which further cleans it.
-Good for diluted soluble contaminents.

47
Q

What are the treatments for different kinds of products with a pump and treat strategy?

A

Usually they use activated carbon to filter and absorb things out. Itrs a universal solution for solvents
-catalyst. thermal degradation for a pollutant that can be broken down into a less harmful form
-forced metal precipitation for heavy metals
-oil water separator for gasoline and such but not BTEX

48
Q

What is SVE/AS

A

a technology to force a volatile compound into a gas form

49
Q

What is bioremediation?

A

acceleration of microbial degradation used when you have a contaminant that can be broken down by bacteria by adding oxygen

50
Q

What is photremediation?

A

Like bioremediation but you need a hyperaccumulator that can take the pollutuon out the ground and then they burn the plants and dispose of the ash. This makes the pollutant take up less space making it easier to dispose of. Mostly used for heavy metals

51
Q

What are the forces acting on gw movement?

A

Gravity, atmospheric pressure, molecular adhesion, molecular cohesion

52
Q

What forces prevent gw movement?

A

Friction and sheer, attraction of molecules as they slide past each other

53
Q

how many feet in a meter?

A

3.28

54
Q

how many cm in a meter?

A

100

55
Q

how many grams in a kg?

A

1000

56
Q

gal/min into feet/day, how?

A

multiple by 192

57
Q

cm/s to m/day

A

864

Soil and Water (1 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions