Chapter 1 Flashcards
Intrusion of seawater into groundwater basins results from _
Over-pumping from coastal groundwater basins
What is the basic objective of the operation of water treatment plants?
Provide safe, aesthetically pleasing water at a reasonable price
What is one characteristic of a community water system?
Has at least 15 service connections used by all-year residents or regularly serves at least 25 all-year residents
What influences the size of a water treatment plant as well as the number and types of processes it uses?
The impurities in the raw water
Water quality standards
Demand for water by the population being served
Fire protection
Cost considerations
Which Plant operating guidelines are routinely monitored by water treatment plant operators?
Flows and water quality indicators
What is one purpose of clear wells or plant storage reservoirs?
Provide the necessary operational storage to average out high and low flow demands. Acts as a buffer that prevents frequent ON/OFF cycling of finished water pumps and permits planned changed in treatment plant operation.
How would you verify the actual raw water flow rate after adjusting the pumping rate to a water treatment plant?
Reading the raw water flow measuring device and periodically check the storage levels in the clear well and service storage reservoirs to determine if they are meeting volume.
How are the initial selection of chemical types and anticipated feed rates for a given application in a water treatment plant usually determined?
Pilot-plant testing of the specific source water.
What is the best source of information about dangerous chemicals?
Safety data sheet
The chlorine cylinder in service has less than 1 day’s chlorine supply remaining. Three 150lb chlorine cylinders are in storage. The plant uses an average of 28lbs of chlorine per day. How many days of chlorine is available?
3*150 = 450
450/28 = ~16
Which of these chemicals is one of the most dangerous common alkalies?
Caustic soda
What should you do if an operator is not breathing due to chlorine gas exposure?
Perform hands-only cardio-pulmonary resuscitation (CPR). Push hard and fast in the center of the chest. Continue until breathing or help arrives.
Water samples taken to measure compliance with water quality standards are usually collected at _
Where water enters the distribution system.
In a water treatment plant, turbidity is commonly monitored at _
Source water, flocculation effluent, sedimentation effluent, and filter effluent
The range of turbidity removal effectiveness is important because of the relationship between turbidity and _
Bacteria and other pathogenic organisms
Federal laws include sludge from a water treatment plant as a _
Industrial waste
What should an operator promptly do when a treatment process upset results in the failure to meet a specific drinking water quality standard?
Notify supervisory personnel and the appropriate health authorities. In extreme cases, process shutdown and public notification may be required.
If a water treatment plant must be dewatered for emergency repairs, how would you prepare for this event?
Empty all storage reservoirs before repairs
What kinds of records are operators required to keep on file for specified time periods for regulatory compliance?
Water quality analyses and customer complaint records
What is one way of keeping track of how much time and money is spent doing various types of work?
The work order system
How can energy requirements for lighting be reduced in a water treatment plant?
Turn off lamps in unoccupied areas
What regulations require that accurate records of water treatment plant operations be maintained?
The National Primary Drinking Water Regulations of the Safe Drinking Water Act
What contributes to the most treatment plant accidents?
Carelessness and negligence
What is the responsibility of water treatment plant operators?
The production of safe and pleasant drinking water
What do most states require for someone to work as a water treatment plant operator?
Operator certification
Acid Rain
Precipitation that has been rendered acidic by airborne pollutants
Alkalinity
The capacity of water to neutralize acids. This capacity is caused water’s content of carbonate, bicarbonate, hydroxide, and occasionally borate, silicate, and phosphate. Expressed in milligrams per liter of equivalent calcium carbonate.
BOD
Biochemical Oxygen Demand. The rate at which organism use the oxygen in water while stabilizing decomposable organic matter under aerobic conditions.
Chlorine residual
The concentration of chlorine present in water after the chlorine demand has been satisfied.
Coagulant
A chemical that causes very fine particles to clump together into larger particles.
Coagulation
The clumping together of very fine particles into larger particles cause by coagulants.
Coliforms
A group of bacteria found in the intestines of warm-blooded animals and in plants, soil, air, and water. Fecal coliforms are those found in the feces of warm-blooded animals.
Composite Sample
A collection of individual samples obtained at regular intervals, usually every one or two hours during a 24-hour time span.
Corrosion
The gradual decomposition or destruction of a material by chemical action often due to an electrochemical reaction.
Floc
Clumps of bacteria and particles or coagulants and impurities that have come together and formed a cluster. Found in flocculation tanks and settling or sedimentation basins.
Flocculation
The gathering together of fine particles after coagulation to form larger particles by a process of gentle mixing. this makes it easier to separate the solids from the water.
Grab Sample
A single sample of water collected at a particular time and place that represent the composition of the water only at that time and place.
Jar Test
A laboratory procedure that simulates coagulation/flocculation with differing chemical doses. Used to estimate the minimum coagulant dose required to achieve certain water quality goals.
Pathogenic Organisms
Organisms capable of causing disease.
pH
An expression of the intensity of the basic or acidic condition of a liquid.
Power Factor
The ratio of true power passing through an electric circuit to the product of the voltage and amperage in the circuit.
Raw Water
Water in its natural state before any treatment, water entering the first treatment process of a water treatment plant
SDS
Safety data sheet, usually provided by a chemical retailer that offers information on how to best handle chemicals.
Sedimentation
The process of settling and depositing of suspended matter carried by water or wastewater.
Sludge
The settleable solids separated from liquids during processing.
Toxic
A substance that is poisonous to a living organism. Toxic substances may be classified in terms of their physiological action.
Turbidity
The cloudy appearance of water caused by the presence of suspended and colloidal matter. Technically an optical property of water based on the amount of light reflected by suspended particles.
Weir
A wall or plate in an open channel used to measure or control the flow of water.
Clear Well
A reservoir for the storage of filtered water of sufficient capacity to prevent the need to vary the filtration rate with variations in demand. Also to provide chlorine contact time for disinfection.
