Drinking Water

Question 1

The discharge from filters flows into a storage reservoir also called a

Answer 1

a Clearwell

Question 2

What technique is effective at removing 50 to 95% of the algae that is from the influent water

Answer 2

microstrainer

Question 3

Which of the followING is needed to determine the minimum fire suppression storage?

Answer 3

required fire flow rate and the duration of fire flow rate

Question 4

what are the four main zones of the settling tank

Answer 4

inlet, sludge, settling and outlet

Question 5

Which of the following types of settling occurs when individual particles settle independently

Answer 5

Discrete

Question 6

which of the following terms describes the surface charge that the sub-micron particles carry that cause them to repel each other so they cannot collect to form larger particles

Answer 6

Colloidal***

Question 7

Which of the Following terms describes the pH at which the zeta potential of the particle is zero

Answer 7

Iso-electric point

Question 8

Paddles are used to gently mix the water in the flocculator, Which is greater the velocity of the paddle or the velocity of the water?

Answer 8

Velocity of the paddle - this is because of the slip the slip is represented by the factor k in the equation for the water velocity

Question 9

what is the most basic test used on the effectiveness of coagulation/ flocculation

Answer 9

jar test

Question 10

Once coagulant has ben added to the treated water, the particles become net neutral. What is the forces acting to attract the particles that no net charge?

Answer 10

VAn der Waal forces are weak forces that work to attract particles together that have no charge

Question 11

As alkalinity increases, what happens to the capacity of the water to neutralize acids

Answer 11

Increases - Alkalinity is the measure of how well a sample can neutralize an acid. The more alkalinity in water, the better the water can neutralize acids

Question 12

What does reverse osmosis accomplish during water treatment?

Answer 12

It is an effective way to remove contaminants, it removes ions, molecules and large particles from drinking water.

Question 13

what are the 7 basic steps for water treatment?

Answer 13

1. Coagulation
2. Flocculation
3. Sedimentation
4. Filtration
5. Disinfection
6. Storage
7. Distribution

Question 14

What is the purpose of aeration during drinking water treatment?

Answer 14

Aeration during Drinking water treatment is primarily to reduce taste and odor causing compounds in the system.

Question 15

Where is the storage reservoir typically located on a suite that is also serviced by a pumping station

Answer 15

The storage reservoir will typically by located on the opposite side from the pumping station, During periods of high water consumption, the site can be fed from both sides which decreases the head in the mains.

Question 16

What is Effective storage

Answer 16

it is total storage minus the dead storage

Question 17

The presence of methane gas occurs in the groundwater because of the decomposition of organic matter, How is it removed?

Answer 17

Aeration, during the process air is mixed into the water which leads to the has being vented to the outside atmosphere

Question 18

where are cyanophycean found?

Answer 18

both salt and fresh water, floating near the water surface

Question 19

what color are cyanophycean?

Answer 19

they are blue-green in color

Question 20

What is a main culprit of taste and odor complaints?

Answer 20

cyanophycean

Question 21

Name three methods/ materials used for oxidation

Answer 21

Potassium Permanganate, Chlorine Dioxide and Ozone

Question 22

What are THMs’?

Answer 22

Trihalomethanes, are the byproducts of the chlorination of water that has natural organic matter present

Question 23

What is the technical term/ test for the amount of Odor in water

Answer 23

Threshold Odor number/test, determine the amount of odor in the water. During the test dilutions are presented of a sample and the last dilution in which the odor can be detected is called the threshold odor number

Question 24

What are advantages of powdered activated carbon

Answer 24

Low initial cost and dosage flexibility

Question 25

What are the disadvantages of powdered activated carbon?

Answer 25

large amount of sludge is produced as it cannot be regenerated

Question 26

What materials cause salty taste in water

Answer 26

Sodium, Magnesium, Potassium

Question 27

What is the most common compound used for drinking water treatment in the coagulation process

Answer 27

Alum, or aluminum sulfate is the most common chemicals coagulant used for drinking water treatment in coagulation process

Question 28

What is the purpose of coagulation?

Answer 28

To remove small particulate matter that is suspended in the influent water

Question 29

What is tapered flocculation

Answer 29

also called tapered energy - the process with which the amount of flocculation gradually diminishes as the water progresses through

Question 30

Name two reasons there could be poor floc formation and a test that can be done?

Answer 30

Poor Flocc formation can be a symptom of either an inadequate coagulant dose or improper detention time. These can be tested using a simple jar test to model what the problem is?

Question 31

Name 3 advantages of UV in disinfection for drinking water?

Answer 31

1. does not form harmful by-products 2. Does not create an unpleasant taste or odor 3. Effective on a large range of pathogens

Question 32

Name 3 things that help determine the location of a water treatment plant?

Answer 32

Location of location water, Location of power sources, Sewer services for the plant

Question 33

Name 3 factors used in sizing atmospheric storage tanks?

Answer 33

Emergency reserve storage, future growth of the system, fire flow storage

Question 34

What is the recommended standby storage for systems served by a single source supply?

Answer 34

two times the average day demand

Question 35

What does activated carbon mainly attract from liquid and vapor?

Answer 35

organic materials, Activated carbon attracts only a small variety of inorganic chemicals

Question 36

What chemicals are more likely to produce a rotten egg odor in drinking water

Answer 36

Hydrogen sulfide

Question 37

What makes a garlic-y taste in water?

Answer 37

Methane

Question 38

What is something creates a earthy or grassy odors

Answer 38

Geosmin

Question 39

Two main categories of coagulating chemicals?

Answer 39

ionic polymers and hydrolyzing metal ions

Question 40

What can bentonite clay be used for in the flocculation process

Answer 40

as an additive to weight down the flocs

Question 41

What does it mean to agglomerate

Answer 41

gathered into a ball, mass, or cluster. specifically : clustered or growing together but not coherent.

Question 42

what is the optium pH for Alum?

Answer 42

typical operation is 6-7 but is effective with 5.5 to 8

Question 43

name 3 devices used for agitation for rapid mixing and flocculation

Answer 43

Mechanical agitator, pneumatic agitator and baffle basin

Question 44

name three types of flocculation additives to improve flocculation?

Answer 44

Polymers, Colloidal clay and activated silica

Question 45

the purpose of coagulation/ flocculation is to turn what into floc?

Answer 45

Turbidity - Settling out the floc works to eliminate the impurities that create turbidity

Question 46

Can Activated carbon remove Radon?

Answer 46

Yes

Question 47

Can Activated carbon remove Pathogens?

Answer 47

NO

Question 48

Can Activated carbon remove VOCs?

Answer 48

Yes

Question 49

Which of the following tpes of sedimentation occurs in the lower parts of the clariferiers when the concentration of particles is the highest

Answer 49

Discrete

Question 50

what is an Aldehyde

Answer 50

an organic compound formed by the oxidation of alcohols. The occur naturally in the environment, and are potentially/consdiered carcinogenic and mutagenic, and sometimes cause odor

Question 51

What are typical aldehydes

Answer 51

methanol (formaldehyde) and ethanal (acetaldehyde)

Question 52

How are aldehydes found in water

Answer 52

it orginates from many sources such as : 1. oxidation processes, 2. photochemcical transformations 3. life processes of animals and plants 4. decomposition of organic matter 5.Formed in the atmosphere, anthropenic origin. 6. By-product of disinfection with Chlorine

Question 53

what is an instanteous slug dose

Answer 53

an addition of a chemicals to a system is one big dose, mixing then occurs Disadvantage of this technique is very concentrated solutions and intensive mixing is required

Question 54

what is the drinking water standard for methane gas

Answer 54

while no drinking water standard exists for methane gas however there is a warning level of 10 mg/L and levels about 28 mg/L could release flammable amounts

Question 55

What are the risks of methane gas in drinking water

Answer 55

Methane can be flammable and explosive when mixed with oxygen. it can also displace oxygen which would cause suffocation when released in a confined space Can cause issues with pumps and water systems

Question 56

What color and odor does methane gas have?

Answer 56

Colorless and odorless, and tasteless however Production-grade methane is marked by a pungent odor from mercaptan; a chemical odorant added to methane by a gas company before distribution to help in leak detection

Question 57

what are some solutions for methane gas in drinking water

Answer 57

air stripping, aeration, and or a tall vent that would avoid any flammable or confined space hazards

Question 58

What is a Phenol

Answer 58

mildly acidic chemical in the -OH family, usually caused by polluted waste water, Phenolic compounds are also found naturally occurring in bodies or water. and also some phenolic compounds are associated with different colors of flowers and fruits

Question 59

What is the risk of Phenols in drinkingwater

Answer 59

Drinking water with extremely high concentrations of phenol has caused muscle tremors, difficulty walking, and death in animals.

Question 60

Methods on removing phenols from water?

Answer 60

adsorption, extraction, polymerisation, electro‐coagulation, photocatalytic degradation, biological methods, electro‐Fenton method, advanced oxidation processes, adsorption and ion exchange and membrane‐based separation techniques

Question 61

describe Osomsis

Answer 61

The basics - weaker saline(salty) solution will migrate to a stronger saline solution, Example - plant roots absorbing water for the soil and our kidneys adsorbing water from out blood

Question 62

Describe Reverse Osomsis

Answer 62

the opposite of regular osmosis, force must be used to make this occur. basically a solution passes through a membrane that separates dissolved solutes from water, IE salty solution moves through the filter and joins a less salty solution

Question 63

What is the difference between Reverse Osmosis and Osmosis

Answer 63

Osmosis occurs naturally, and Reverse Osmosis must have force applied to be make process occur, also the obvious difference is Regular Osmosis makes a salty solution and Reverse makes a "cleaner" pure solution

Question 64

what are two types of Rapid Sand filters

Answer 64

1. Rapid Gravity 2. Rapid Pressure the only difference is speed

Question 65

For dual media filters, what does the upper layer of coal trap do?

Answer 65

The upper layer of coal traps most of the large floc, and the finer sand grains in the lower layer trap smaller impurities

Question 66

Name three advantages of of Dual media filters

Answer 66

main advantages of multimedia filters compared to single-medium filters are longer filtration runs, higher filtration rates, and the ability to filter a water with higher turbidity and suspended solids.

Question 67

What is the pore size range of ulta-filtration membranes?

Answer 67

pore sizes in the range of 0.02 – 0.05 micron

Question 68

Ultra Filtration membranes can remove what four things?

Answer 68

bacteria, viruses, colloids, and silt

Question 69

What is backwashing

Answer 69

reversing the flow of water through a home treatment device filter or membrane to clean and remove deposits

Question 70

what is dredging?

Answer 70

removal of mud from the bottom of water bodies. This can disturb the ecosystem and cause silting that kills aquatic life. Dredging of contaminated mud can expose biota (the flora and fauna of a region) to heavy metals and other toxics. Dredging activities may be subject to regulation under state and federal laws.

Question 71

define echard

Answer 71

water in the soil not available to plants

Question 72

what is an enteric viruses

Answer 72

a category of viruses related to human excreta found in waterways.

Question 73

what is epilimnion

Answer 73

warm, less dense top layer in a stratified lake. Compare hypolimnion.

Question 74

what is facultative bacteria

Answer 74

bacteria that can live under aerobic or anaerobic condition

Question 75

what is giardia lamblia

Answer 75

a protozoa found in the feces of infected humans and animals that can cause severe gastrointestinal ailments. It is a common contaminant of surface waters

Question 76

what is halolimnic

Answer 76

of, like or pertaining to sea creatures who spend time in fresh water.

Question 77

what is halophilous

Answer 77

tolerant of salt or salt-wate

Question 78

hydropathy is?

Answer 78

study of or treating diseases with water

Question 79

imhoff cone

Answer 79

a clear, cone-shaped container used to measure the volume of settleable solids in a specific volume of water.

Question 80

interfacial tension

Answer 80

the strength of the film separating two immiscible fluids (e.g., oil and water) measured in dynes per, or millidynes per, centimeter.

Question 81

Langelier Saturation Index (LSI)

Answer 81

an index reflecting the equilibrium pH of a water with respect to calcium and alkalinity; used in stabilizing water to control both corrosion and scale deposition.

Question 82

Lindane

Answer 82

a pesticide that causes adverse health effects when present in domestic water supplies and is toxic to freshwater fish and aquatic life

Question 83

methyl tertiary butyl ether (MTBE)

Answer 83

an additive originally put in gasoline to reduce air pollution, but later found to be a source of groundwater pollution

Question 84

mixed liquor

Answer 84

a mixture of activated sludge and water containing organic matter undergoing treatment in an aeration tank

Question 85

polychlorinated biphenyls

Answer 85

(PCBs) toxic industrial chemical compound substances that were used in the manufacture of plastics and as insulating fluids in electrical transformers and capacitors. Banned since 1979, PCBs continue to be found in fish/animals

Question 86

recarbonization

Answer 86

process in which carbon dioxide is bubbled into water being treated to lower the pH

Question 87

trihalomethanes (THM)

Answer 87

chemical compounds in which three of the four hydrogen atoms of methane (CH4) are replaced by halogen atoms. Widely used in industry as solvents or refrigerants. THMs are also environmental pollutants, and many are considered carcinogenic. THMs are generally by-products of chlorination of drinking water that contains organic material.

Question 88

vadose zone

Answer 88

the zone between land surface and the water table where the moisture content is less than saturation (except in the capillary fringe) and pressure is less than atmospheric. Soil pore space also typically contains air or other gases. The capillary fringe is included in the vadose zone.

Question 89

CERCLA

Answer 89

Comprehensive Environment Response, Compensation and Liability Act. Also known as SUPERFUND. The Act gave EPA the authority to clean up abandoned, leaky hazardous waste sites.

Question 90

POTW

Answer 90

publicly-owned treatment works - a wastewater treatment plant that is owned by a state, unit of local government or Indian tribe, usually designed to treat domestic wastewaters. The term also may include devices and systems used by those entities in the storage, treatment, recycling and reclamation of municipal sewage or liquid industrial wastes

Question 91

SRF

Answer 91

state revolving funds - a program, capitalized in part by federal funds, that provides low-interest loans for construction of publicly owned wastewater treatment and water recycling facilities, for implementation of nonpoint source and storm drainage pollution control management programs, and for the development and implementation of estuary conservation and management programs.

Question 92

EIS

Answer 92

Environmental Impact Statement - a document that analyzes the effects of major federal projects on the environment. Required by the National Environmental Policy Act. It must be filed with the President and the Council on Environmental Quality, and made available to the public

Question 93

"first in time, first in right"

Answer 93

phrase indicating that older water rights have priority over more recent rights if there is not enough water to satisfy all rights

Question 94

National Municipal Plan

Answer 94

a U.S. EPA policy created in 1984 to bring all publicly owned treatment works (POTWs) into compliance with Clean Water Act requirements

Question 95

National Oil and Hazardous Substances Contingency Plan

Answer 95

the federal regulation that guides determination of the sites to be corrected under the Superfund program, and the program to prevent or control spills into surface waters or elsewhere.

Question 96

National Pollutant Discharge Elimination System

Answer 96

a provision of the Clean Water Act that prohibits discharge of pollutants into waters of the United States unless a permit is issued that complies with the Clean Water Act. In Texas, the Texas Commission on Environmental Quality (TCEQ) administers the NPDES program and issues TPDES permits.