Wastewater Operator Class 1 & 2 Practice Test

Flow measurement system where flow stream contents are collected in container for fixed period of time

Timed gravimetric

Uses a strong oxidizer to break down organic material

Chemically Oxidizable Carbon (COD)

a measure of carbon dioxide given off when material is heated to 550°

Total Organic Carbon (TOC)

What is the recommended detention time for a primary clarifier?

1 1/2 - 2 hours

What would be added to a lagoon/pond to subdue a strong odor and increase oxygen (O2)?

Sodium Nitrate

What is the maximum holding time for fecal coliform alanyses?

6 hours

What sort of system do lagoons/ponds form for the wastewater organix population?

Aerobic, Anaerobic, Facultative

What is the primary function of a brush aerator?

To produce great dissolved oxygen (DO)

If the first pond in a series operation is organically overloaded, how should the flow be controlled?

They should be switched to parallel operation

What should the operator do with plants/weeds growing along the water's edge with respect to ponds?

Remove them as they appear to avoid the establishment of a deep root system

How should lantern rings be installed on the stuffing box as part of a pump unit?

Completely filled with grease before all the rings of packing are in place.

What are the pH parameters outlined by KPDES in the process of wastewater treatment?

6.0 - 9.0 ppm

The explosive range of the main product of anaerobic digestion, methane, is in the range of:

5-15%

Recirculation in a tricking filter operation is sometimes used with trickling filters to:

Keep the media wet during low flow periods, dilute the organic strength of the influent, and smooth out diurnal flow fluctuations

Small quantities of sludge should be pumped often in primary clarifiers to:

To prevent hydraulic & organic overloading of the digester and to keep sludge blankets down so that the septic "floating" sludge will not result.

In an active oxidation ditch, how long should a measured amount of wastewater treated before going to the next stage?

18-36 hours

Fish such as salmon and trout cannon tolerate more than trace amounts of chlorine. therefore, a total residual chlorine monthly limits for zero flow streams are set at:

0.01 mg/L

The most severe penalties an operator can be subjected to for negligence and violation of EPA regulations are:

Civil or criminal penalties

In an active oxidation ditch, what flow can the operator control?

Return sludge flow and waste sludge flow

What should the operator do when algae forms on a lagoon?

Nothing, it produces oxygen

Samples to be analyzed for ammonia can be held:

28 days, preserved with H2SO4 (Sulfiric acid) to a pH <2.0 at 4°C

Sludge blanket depths may be measured by using what instrument(s)

Sludge judge, sludge light, and core taker

What is the recommended way of keeping weed growth down in ponds?

Maintain a depth of at least 3 feet

What are stuffing boxes used for on a pump?

To prevent air from being sucked into the pump

The aeration basin if operated within recommended parameter, will contain:

Light colored foam that dissipated after traveling a short distance

What is the maximum holding time for pH measurement?

Analyze immediately

A white coating formed on the elements of a rotating biological contactor (RBC) is an indication of:

Septic conditions

The predominant element produced by a well-functioning anaerobic sludge processor is:

Methane gas

A sudden increase in amperage being pulled by a pump motor could be an indication of:

A pumping restriction

When visitors are touring your plant your greatest concern should be:

Their safety

Where are lantern rings installed on a pump?

Between the water supply line and the stuffing box

What must be checked for when using a float type influent gage?

Grease and/or rag buildup on the float

The pretreatment area of a plant is equipped with a comminutor and large solids are getting into the primary clarifier. What might be the problem?

Misaligned teeth or worn teeth

What is the standard design criteria for Total Suspended Solids?

0.20 lbs/capital/day

A newly created pond/lagoon will establish a thriving biological population for waste reduction in about how many days?

60 days

The grit removal process is so important because of why?

It protects downstream equip,emt

You arrive at a manhole where strong gas fumes are detected. What should you do?

Do not enter and call the police/fire department

What type of sample indicates the character of the wastewater over a period of time, eliminates short duration effects, evens out high and low flows, and is a representative sample?

Composite sample

What is the actual EPA directed maximum Cl2 residual allowed in the efflluent?

0.019 ppm

A sudden increase in organic loading on the biological treatment system, with an acidically low pH, is known as a what?

Shock load

At what VA/TA ration would an anaerobic digester be under stress from volatile acids/compounds?

0.3-0.4

Metal plating wastes may be treated with:

Sodium Sulfide

Effluent disinfection is necessary in order to do what?

Kill pathogenic bacteria

Denitrification and rising sludge in the final clarifier may be an indication of:

Low dissolved oxygen

A spill or dump of unknown origin, which could be harmful to the treatment process or the operator(s), is known as what?

Slug load

A grab sample is taken:

at "maximum" conditions such as high flow

Before working on electrical wires, circuits, control boards, or motors the operator should do what?

ensure that all power sources are locked out and tagged out

Sulfur dioxide is the dechlorinating chemical of choice because it reacts almost instantaneously with chlorine on a theoretical basis of what?

1 ppm SO2 to remove 1 ppm Cl2

What is the process for running the total suspended solids test?

Weigh dry filter, filter sample, dry at 103° C for hour, place in desiccator 15 minutes, weigh

Foam coming out of the top valve of a newly filled anaerobic digester is an indication of:

Normal conditions

Sludge floating to the surface of a clarifier is an indication of what?

Denitrification

What characteristics make up an approved light source for use in a manhole?

Explosion proof and reflective

One (1) pound of algae is capable of producing how many pounds of oxygen?

1.6 pounds of O2

What is the purpose of wearing rings in a pump?

To plug the space between the impeller and the casing to prevent internal leakage

What is the minimum detention time recommended for disinfection with chlorine?

30 minutes

Typical design for rock media depth in n intermediate rate trickling filter is what?

6-8 ft

The organic loading rate in lbs soluble BOD/1000ft^2 in an RBC Is:

<2.5

A primary cause for denitrification in a secondary clarifier is:

Low dissolved oxygen

A wastewater treatment facility with a capacity of 2.0-7.5 mgd is classified as what class?

Class III

The flow velocity in the collection system should be at least how many feet per second?

2.0 fps

The standard design criteria for BOD5 is:

0.17 lbs/capital/day

What is the purpose of sleeves in a pump?

To cover the shaft that supports the impeller to protect the shaft from the corrosive and abrasive effects of the liquid going through the pump

Bar screens are normally installed at what angle?

45-60° angle

The detention time in a final clarifier for a facility utilizing a fixed film reactor is:

2-3 hours

Collection system construction requirements, an infiltration or exfiltration test must be performed with a minimum positive head of:

2 ft

Wastewater is composed of what?

99.9% water and 0.1% solids

The nutrient requirements for biological stabilization of organic matter result in the following ratio for Carbon/Nitrogen/Phosphorus

100/5/1

Plastic media in a super high-rate trickling filter system should be at what depth?

10-40 ft deep

Beggiatoa is a

filamentous organism

At what point in the treatment process should a fecal sample be grabbed?

At the last point of the treatment process

There are three general types of grit chambers. In the horizontal channel, velocities are reduced to ______ fps so that the grit will settle while the organics remain in suspension.

1-1.5

Which is a type of diffuser: a ball, a bubbler, or electrical?

A ball

A two stage trickling filter system is designed for a minimum BOD5 removal efficiency percentage of:

85%

What type of foam should be seen at the initial start-up of aerators

Crisp, white

Flow into an RBC should not exceed the design flow by more than what percentage?

50%

Which of the following does not cause filamentous: low dissolved oxygen, toxicity, low f/m (food to microorganism ratio), chlorination

Chlorination

It takes ___________ ppm of alkalinity to convvert 1 ppm nitrate (NO3).

7.2

Sludge blanket depth in a final clarifier should be maintained at what feet?

1.0-3.0 ft

The lethal dose of chlorine with a few breaths is:

1000 ppm or .1% by weight

An approved method of measuring chlorine residual is:

Amperometric Titration

What percentage of BOD is soluble?

50%

Heavy metals, Phenols & Toxins would be classified as what kind of pollutant?

Non-conventional

How much oxygen is needed to oxidize 1 ppm Ammonia to Nitrate?

4.5

Cadmium, Lead, Nickel and Zinc are classified as what kind of pollutant?

Priority pollutants

To improve disinfection by chlorination, it is recommended that the detention time be:

Increased

How much chlorine is required to oxidize 1 ppm ammonia, assuming adequate pH. alkalinity, and temperature?

9.0

How is the initial SO2 dosage determined?

Cl2 residual + 3.0 mg/L

pH, DO, BOD, NH3N, SS, and Cl2 are classified as what kind of pollutant?

Conventional pollutants

A KDPES permit establishes what?

What can be discharged, discharge limits for each parameter, how much can be discharged, sampling frequency, and sample collection method for each discharge parameter

Types of sampling:

Composite and grab

What is a grab sample?

Collected at one moment in time at a single location and is representative of the conditions at that instant the sample was taken

What is a composite sample?

Equal volumes samples taken every 15 minutes over a 24 hour period and aggregated by an automated device.

Why do we aggregate composite samples?

The aggregate samples will reflect the average water quality of the compositing or sample period

If you know your effluent you know what?

Your influent. What goes in has to come out.

How much BOD must be discharged before being discharged into the waters of the common wealth?

85%

How much phosphorous does a person contribute to a wastewater system per day?

0.0048 lbs

Microorganisms/bacteria make up about ______ of the activated sludge biomass.

95%

Synthesis:

production of new cells ***can not work without respiration

Respiration:

Process of deriving energy from carbonaceous organic matter, BOD5, aka food. *** can not work without synthesis

Synthesis needs ______ and respiration needs a ______

energy, living cell