Water Treatment Grade 4 exam prep

which disinfectant would work best against Cryptosporidium

Ozone

The pH of a Water sample Is greater than the PHs so the Langlier index

indicates the water is scale forming

When water high in calcium bicarbonate is softened by ion exchange

Sodium Bicarbonate remains in the product water

A bypass valve would be used with a

gate valve

Where ground frost is expected the riser pipes in a meter pit should be atleast how far away from any wall of the meter box to prevent freezing

1-2 inches

which type of pipe joint is available in both bolted and bolt less flexible pipe joint designs

Ball and Socket Joint

which type of pipe joint permits flexible pipe alignment is inexpensive to manufacture and is easy to assemble

push on joint

new polyvinyl chloride pipe has a c-value of about

150+

which type of valve would be particularly useful for throttling the flow of corrosive liquids

pinch valve

Water meter pits are usually used in

cold climates

fuel oil will permeate which type of pipe

polyethylene pipe

An ion exchange softener is treating a flow rate of 125 gpm. what is the operating time in hours if the softener unit treats 297000 gallons before it requires regeneration?

39.6 hr

in describing pump operation what type of curve shows the relationship between power and capacity

P-Q curve

What is Head Loss

energy used by water when moving from point to point

Static Suction Lift

Difference in water placement

What is Power

Work done in a given time

if a water system collects at least 40 samples per month for the analyses of total coliforms, what percentage of total coliform samples are acceptable for the system to remain in compliance with the maximum contaminant level for total coliforms

no more than 5%

water systems are required to achieve at least________ removal and or inactivation of viruses between a point where the raw water is not subject to recontamination by surface water runoff and a point downstream before or at the first customer.

4 log

where are the sampling points located for required samplings of organics (except THMs) in a community water system

entry points to the distribution system

where are the sampling points located for required sampling of natural radionuclides in a community water system

each entry point to the system

continuous chlorine residual monitoring is required where the water enters the distribution system under the SWTR when the

population served is >3300 people.

a community water system must post the consumer confidence report on a publicly accessible website if it serves more than

100000 people

public water systems that cannot meet the required removal of TOCs can comply if the source water TOC level is ________ calculated quarterly as a running annual average

the Surface water treatment rule does not specify which of the following treatment technology

chloramine disinfection

a regulated organic contaminant concentration that exceeds the MCL

is a teir 2 violation requiring public notification withing 30 days

operators must balance satisfying regulations on the amount of certain chlorinated organic compounds with

meeting disinfection limits

a water system using conventional filtration treatment does not have to use enhanced coagulation to achieve the total organic carbon percent removal if

the treated water quarterly running average TOC is less than 2.0 mg/L

the stage 1 DBPR established an MCL of _____ for TTHM ( total THMs)

.08 mg/L

the safe drinking water act defines a public water system as a supply of piped water for human consumption that has at least _______ service connections, or serves _______ or more persons 60 or more days each year

15;25

under the enhanced coagulation requirement ls of the DBPR treatment plants must remove specific percentages of total organic carbon based on their source water total organic carbon and what other factor

Alkalinity levels

the filter backwash recycle rule applies to what sizes of systems

all sizes

which rule most directly guards against the presence of escherichia coli in the water supply

total coliform rule

which type of sample should always be collected for determining the presence of coliform bacteria

grab sample

what chemical element is used to remove chlorine from water

NA2S2O3

water that is to be analyzed for inorganic metals should be codified with

concentrated nitric acid

a typical coliform colony in the membrane filter method has the following characteristics

pink to dark red with a green metallic sheen

which of the following is the first level of dissolved solids that is considered unfit for human consumption

4000 mg/L

which type of special photometer is used to analyze for heavy metals in water

Atomic Absorption Spectrophotometer

in the multi tube fermentation method which type of culture media is used in the confirmed test

green lactose bite broth

all positive samples in the presence absence test must be confirmed using

Brilliant Green Bile tubes

what is PHs?

pH saturation

______ is a measure of the hydrogen ion concentration presence in water

pH

what steps are involved in the MTF method

Presumed, Confirmed, Completed tests

Conductivity is a measure of the ability of an aqueous solution to do what

carry current

Describe the characteristics of carbon dioxide

Colorless odorless and naturally occurring in all water

in regard to the testing of coagulant effectiveness which method is the most readily available to most operators and has been commonly used for years

Jar test

which of the following does the saturation point of calcium carbonate primarily depend upon

PH

which of the following will increase pH, Hardness, and Alkalinity?

Lime

which chemical used for stabilization of potable water is a bacterial nutrient?

polyphosphate

wastewater water quality discharge requirements could be exceeded if which of the following chemicals are used for corrosion control in the water system

Hexametaphosphate

Lime is commonly used for corrosion control because

it can adjusts both PH and Alkalinity

Buildup of corrosion products ( a process known as ______) or uncontrolled scale deposits can seriously reduce pipeline capacity and increase resistance to flow

tuberculation

unslaked lime

quicklime

Of the metals tin, Zinc and Aluminum which us the most likely to corrode

Zinc

what is the principal source of excessive lead and copper in customers water

corrosion of household plumbing

the three reasons that lime is the most common chemical used for PH and Alkalinity Adjustment

Availability, Inexpensive, easy to feed

CaCO3 is the _______ of calcium Carbonate

chemical formula

Molarity is the number of

moles of solute per liter of solution

The first step to calculating percent by weight of an element in a compound is to determine the

molecular weight

what term refers to the number of equivalent weights of solute per liter of solution

normality

a solution consists of two parts; a solvent and a

solute

how many atoms of oxygen are present in Ca(HCO3)2?

6

water being served to the public for a population greater than 3300 must not have a disinfection residual entering the distribution system below ______ for more than 4 hours

.2 mg/L

what is the action level of copper

1.3 mg/L

where are the sampling points located for required sampling of turbidity in a community water system

at points where the water enters the distribution system including all filter effluents of a surface water treatment plant

under the SWTR, disinfection residual must be collected at the same location in the distribution system as

coliform samples

what is the MCL for haloacetic acids (HAA5)?

.06 mg/L

An example of _______ is determining the lowest monthly average during a 12 month monitoring of giardia and virus inactivation

benchmarking

what is the MCLG of substances that are expected carcinogens

zero

what is the optimal ph range for the removal of particulate matter when using alum as a coagulant

6.5 to 7.2

which forces will pull particles together once they have been destabilized in the coagulation-flocculation proccess

Van der Waals force

which of the following is a common mistake that operators make in regard to flocculation units

excessive flocculation time

ferric sulfate has what advantage over alum as a coagulant

more dense floc

the lower the _____, the more difficult it us to form proper floc

turbidity

jar tests are expressed in

milligrams per liter

list 4 characteristics of raw water that must be considered in selecting a treatment chemical

PH, Temperature, Alkalinity, TOC, and Color

Raw water temperature that approaches the freezing point has what effect on coagulation and flocculation proccess

it slows down the speed of the proccess by making floc settle slower and making the water denser

If enteric disease causing protozoans have been found in the effluent of a water plant which of the following is the most probable solution

Using the multi barrier approach- coagulation, Flocculation, Sedimentation, and Filtration

what is the major cause of short circuiting in a sedimentation basin

poor inlet baffling

conventional sedimentation has a _________ removal of cryptosporidium oocysts

less than .5-log

dissolved air flotation is particularly good for removing

algae

as solids settle to the bottom of a sedimentation basin

a sludge layer develops

what is the maximum weir loading for light alim floc in solids contact basins

10gpm/ft

list four components of a typical rectangular sedimentation basin

Baffle, Adjustable Weirs, Sludge Pump, Collector drive

which regulation basically requires that surface water systems maintain specified C x T values before the treated water reaches the first customer

SWTR

what is the primary test used to indicate poor sedimentation

test for turbidity

which type of sludge cannot be discharged to a sanitary sewer system because its deposits might build up and block sewers

lime sludge

the rule of reasonable sharing of water is usually called

Riparian Doctrine

the rule the landowners can capture all the water under their land is called

absolute ownership

the rule that a landowner has the right to the groundwater as long as it does not harm a neighbor us called

reasonable use

which rules applies when the most important issue is priority, where water rights are based on who has used the water for the longest time

Appropriation-permit systems

which of the following would be the most probable solution to control algae in the source water if the algae were clogging the filters at the water plant

control nutrients

A conventional water treatment plant in a rich farming area has to treat water high in nitrates. which if the following is it's best course of action in the long term

manage watershed to prevent nitrates from entering the water system

when a water source is destroyed or damaged due to some disaster that causes total contamination which of the following would be a short term goak

draw water from an adjoining system or systems

the main objective of a customer complaint response system is to

address the customers concerns

typically, the greatest amount of water in residential use can be attributed to the

toilet

water use rates for a community are typically highest at what time of day

6 p.m. to 10 p.m.

what are two general categories of carastrophies that can disrupt the operation of a water source

Natural and human disasters

what system is based on the principle that the owner of the land owns everything beneath that land all the way down to the center of the earth

absolute ownership

list 3 undesirable effects of implementing a water concentration program

Less income difficulty in droughts, and delay in developing additional sources