Waste water study guide class one

When organic wastes are discharge to receiving waters, oxygen is depleted by What?

bacteria

Employee hazards include

Noxious or toxic, gas or vapor

Oxygen Deficiency

Physical injuries

Hydrogen sulfide Gives off an older similar to what

Rotten eggs

coliform bacteria are what.?

Indicators

Three waterborne diseases are

Typhoid fever

Dysentery

Cholera

A cyclindrical tank is 10 feet in diameter and 20 feet. What is the approximate capacity gallons

11,750

First aid for first-degree burns is to

Submerge the burned area in cold water

Which of these pH readings indicates an acidic wastewater

3

If water weighs 8.34 Pounds per gallon, how much will 7 ½ gallons weigh

62.5

1 mm is what fraction of a liter

1/1,000

The normal cause of electric motor failure is

Dirt

Moisture

Friction

A pump can deliver 400 gallons per minute at a total head of 184.8 feet. What is the pressure equivalent to this head, expressed in pounds per square inch

80 PSI

How many gallons of waste water would 600 feet of 6 inch pipe, hold, approximately

880

A water seal on a pump serves a dual purpose. It acts as a lubricant and it also.

Keeps gritty material from entering the packing box

The elevation of any pump above the source of supply should not exceed ____ ft.

22 ft

The three common types of plastic pipe are listed as

• PVC

• PE

• ABC

This names referred to the

Composition of the pipe

Prior to repairing a pumps, electrical circuit, which of the following actions should you take?

Disconnect the circuit Breaker, place a red tag, stating “do not activate”, and lockout

Pump maintenance includes

Checking operating temperature of bearings

Checking packing Gland

Operating two or more pumps of the same size Alternately to equalize wear

When carrying out a routine inspection on a centrifugal pump, it is noted by the operator that the bearings are excessively hot… This could be caused

Over lubrication

In a centrifugal pump, internal leakage is prevented by

Wear rings

A valve which allows water to flow in one direction only is a ____

Check

Pipe material that is the least susceptible to corrosion by acids formed from hydrogen sulfide gas is

CIP

Centrifugal pump parts include

Impeller

Which indicates a good quality domestic activated sludge?

Brown color and musty

Which of the following forms of plant life is necessary for the proper functioning of a stabilization or oxidation pond?

Algae

Cattails growing in lagoon will

Cause short circuiting in affected lagoon

At what time of day is the dissolved oxygen content HIGHEST in a lagoon?

7am

The greatest bacterial activity, and the highest BOD removal in a waste stabilization Lagoon will occur when there is what?

Warm temperature, moderate breeze, and good sunlight

Chlorine gas is?

Heavier than air

Acid should never be added to chlorine solutions as they…

Cause chlorine gas to be released

As water temperature decreases, the disinfecting action of chorine…

Decreases

The highest concentration of algae growth in a Lagoon is usually observed….

Near top

Which of the following is not a possible cause of short circuiting, in a pond?

High influent BOD

Common setting times in wastewater treatment plants range from…

30 to 45 minutes

Which gas is produced in anaerobic digesters and can be used as a fuel?

Methane

Compute the lagoon detention time (days)

DATA:

SURFACE AREA = 6.0 acres

AVERAGE DEPT = 3.0

AVERAGE EVAPORATION EXCEEDS PRECIPITATION BY 0.4 in/day

AVERAGE DAILY FLOW (influent) = 0.25 MGD

1 acre =43,560 sq. Ft

1 cu. Ft contains 7.5 gal.

24

How many pounds of chlorine gas is necessary to treat 4,000,000 gallons of wastewater at a dosage of 2 mg/L?

67 lbs

Assume a community of 1100 people has a logo. The flow averages 80,000 gallons per Day. The flow is?

72 Gallons per capita

The rock in most trickling filters is placed

On a system of tile under drains

Chlorine is used to…

Disinfect

What is the purpose of heating and mixing a primary anaerobic digester?

To eliminate all oxygen present

The following device is used to measure the flow of waste water

Parshall flume

A spray nozzle on the mechanically cleaned screen has become plugged.

To ensure your safety , prior to entering the screen housing to repair the nozzle, you should…

Turn off and lock motor control

Exhaust from a chlorinator room should be taken from …

At floor level

Which of the following would be the safest action to take in the event of a major chlorine container leak?

Notify local police or sheriff

A composite sample will give a(n)…

Representative sample

Chlorine residual may be determined using the reagent…

Diethyl-p-phenylenediamine (DPD)

Results from the multiple-tuber fermentation technique for members of the total coliform group are expressed as …

MPN

Drawings which are considered “as built” would be..

Corrected construction drawings, showing changes made in the field installation

Sources for more information in training courses are…

Federal, state and local water pollution control agencies

Libraries

Local and national water pollution control associations