Chapter 8 Flashcards
Water is stored to meet peak demand and to allow production facilities to operate at ______ rates
Uniform
Stored water can meet sudden demands such as fire, absorb pressure surges, provide detention /contact time for _____, and allow for expansion of the distribution system
Chlorination
Pressure from an elevated tank is caused by the height of the column of water in ______
Pounds per square inch
The water column must be at least ____feet higher than the highest service connection to be considered elevated storage
80
Roof vents must be screened with ______ mesh or finer corrosion -resistant material
16
All roof hatches must be ______
Locked
Ground water supply systems serving more than 50 connections must have a ground (total) storage capacity of 200 gallons per connection and elevated storage capacity of 100 gallons per connection or pressure tank capacity of 20 gallons per connection. ( true or false )
True
A _______, internal, and documented inspection of all storage tanks is required
Yearly
Potable water storage tank inspection results must be maintained at least ______ year
5
All community systems must post at each production and storage site a sign stating the name ________
Emergency
An intruder - resistant fence with lovable gates must enclose the storage site (true or false )
True
The system must be maintain a minimum pressure of _____psi under normal conditions and at least _____psi during emergencies
35 / 20
Pipe and fittings must not contain more than _____% lead, or solder and flux containing more than ____% lead
8 / 0.2
A ______valve is the most common isolating valve in the distribution system
Gate
Dead end mains must be provided with ________
Flush valves
Service tap components usually include a tapping saddle , corporation stop, service line tubing, curb stop and________
Meter
When trenching, the spoil bank should be more than ______feet from the excavation
2
Trenches or ditches ___feet or deeper should be shored
5
TCEQ requires at least 1 Bac - T sample for each 1,000 feet of new main ( true or false)
True
For a new main , hold a chlorine dose of _____mg/l or more for ______hours
25 / 24
If a repaired main must be returned to service quickly, dose it with _____mg/l for 30 minutes
500
Dead end mains must be flushed at least _______
Monthly
Corrosion results in tuberculation , a mineral build up usually of oxidized _________
Iron
Methods of fighting corrosion include coatings , PH adjustment , and cathodic protection ( true or false)
True
Back flow prevention measures include approved check valve assemblies , vacuum breakers and air gaps ( true or false)
True
The ____ is TCEQs first choice to be used for back flow prevention when health hazards are involved
Air gap
Common cross connections include a garden hose connected to a potable water source and submerged in a stock tank , a home served by a city water supply and private well , and a chemical container connected to a potable water supply ( true or false
True
There are 2 primary categories of pumps : centrifugal and ________ displacement
Positive
The force a pump works against is called head and is measured in feet of water or ______
Psi.
The total dynamic head a pump must overcome is the distance from the water level on the suction side of the pump to the top of the water level on the discharge side of the the pump and includes any friction and head loss encountered. ( true or false)
True
