What is potentially the most hazardous situation to deal with at a water plant?

A chemical spill

What is the recommended finished water target turbidity level?

0.1 NTU

These metallic elements can cause staining of plumbing fixtures and clothes

Iron and manganese

What is the goal of all water plants?

To produce a filtered water with the lowest practical level of turbidity

Most accidents at a water treatment plant are the result of what?

Carelessness and/or negligence

The treatment of water may depend on factors such as the impurities in the raw water source, the finished water quality standards, the demand for the water by the community and what other condition?

Treatment cost considerations

What is the MCL for radium 226 & 228?

5 pCi/L

What is the secondary MCL for iron?

0.3 mg/L

What is the purpose of adding a coagulant, like aluminum sulfate (alum), to the raw water?

To help remove light, fine particles from the water

What are sources of water for a water treatment plant?

A stream, river or well

What are the three major water quality indicators that effect the efficiency of copper sulfate as an algicide?

•Alkalinity, algae species, and outdoor temperature

•pH, chlorine residual and conductivity

•Alkalinity, settleable solids and chlorine demand

•Water temperature, suspended matter and alkalinity

Items essential to a sanitary survey include identification of potential hazards, the determination of factors that affect water quality and which other condition?

•The selection of treatment requirements

•The demand of the finished water product

•The amount of process waste products

•Hiring of qualified operators

A condition where surface waters warm rapidly, expand, and become lighter than the lower, colder waters is called?

Thermal stratification

According to the SDWA, a Public Water System is one that:

Has at least 15 service connections and serves an average of 25 people daily for at least 60 days per year

If a lake has a surface area of 5 acres, what is the surface area as square feet?

217,800 sq ft

Convert 9,785,500 cubic feet to gallons

73,195,540 gallons

Aeration and Re-aeration are methods of what?

Reservoir destratification

A disagreeable rotten egg odor noticed in a groundwater source is caused by what?

Hydrogen sulfide

How many Nephelometric Turbidity Units (NTU) will produce a water that is usually objectionable for aesthetic reasons?

5.0 NTU

Soft water, turbidity, suspended solids and microbial contamination are characteristics of what raw water source?

Surface water