Questions and Answers
In Texas, water operator licensing is administered by the ________.
TCEQ
Which minerals cause hardness in water?
Magnesium and Calcium
The most important federal law impacting the water utility industry is the ________.
Safe Drinking Water Act
The four water quality standards established for drinking water in the Safe Drinking Water Act are chemical, bacteriological, radiological and ________.
Signup and view all the answers
The minimum allowable pressure in the distribution system under emergency conditions is ________.
Signup and view all the answers
Water vapor given off by plants and trees is known as ________.
Signup and view all the answers
Organic matter includes ________.
Signup and view all the answers
The single most important water treatment process is ________.
Signup and view all the answers
Excessive nitrates in drinking water can cause ________ syndrome in infants.
Signup and view all the answers
A sanitary control easement must cover land within ________ feet of a public water well.
Signup and view all the answers
A sample for physical and chemical analysis of a new well must be taken after ________ hours of continuous pumping.
Signup and view all the answers
Chapter 290 Rules and Regulations require chemical analysis of surface water supplies every ________.
Signup and view all the answers
Detention time in sedimentation basins must be at least ________ hours to allow floc to settle.
Signup and view all the answers
Backwashing should expand the filter media by ________ percent.
Signup and view all the answers
In Texas, all public water systems are required to have ________ facilities.
Signup and view all the answers
The MCL for Trihalomethanes in drinking water is ________.
Signup and view all the answers
At room temperature, chlorine gas is greenish-yellow, has a pungent odor, and is ________ times heavier than air.
Signup and view all the answers
Diseases that may be spread by inadequately disinfected water are ________.
Signup and view all the answers
Minimum chlorine residuals of ________ (free) and ________ (combined) are required in the far reaches of the distribution system.
Signup and view all the answers
Parameters that affect coagulation are ________.
Signup and view all the answers
Do not work in a trench ________ feet or deeper unless it is protected from a cave-in.
Signup and view all the answers
Place spoil banks at least ________ feet from the edge of an excavation.
Signup and view all the answers
Dose new water mains with a minimum of ________ mg/L or more of chlorine for at least ________ hours.
Signup and view all the answers
One bacteriological sample is required for each ________ of new completed main.
Signup and view all the answers
A cross connection is a physical connection between a public water supply and 1) another supply of unknown or questionable quality, 2) any source that may contain contamination, and 3) any water ________.
Signup and view all the answers
Maximum spacing between ladders in a trench is ________.
Signup and view all the answers
When should a rapid sand filter be backwashed?
Signup and view all the answers
A ditch 4 feet wide, 6 feet deep and 1,000 feet long will be excavated. How many cubic yards of pipe bedding will be needed to bed the trench 7 inches deep?
Signup and view all the answers
How many gallons will 5,000 feet of 18 inch water pipe hold?
Signup and view all the answers
A tank that has a capacity of 700,000 gallons must be disinfected with a dosage of 50 mg/L of chlorine. How much 65% HTH will it take to achieve the same goal?
Signup and view all the answers
Study Notes
Water Operator Licensing
- In Texas, water operator licensing is overseen by the TCEQ (Texas Commission on Environmental Quality).
Water Hardness
- Hardness in water is primarily caused by two minerals: magnesium and calcium.
Federal Water Laws
- The Safe Drinking Water Act is the key federal legislation regulating the water utility industry.
Water Quality Standards
- The Safe Drinking Water Act establishes four main water quality standards: chemical, bacteriological, radiological, and physical.
Distribution System Pressure
- The minimum allowed pressure in a water distribution system during emergencies is 20 psi.
Plant Water Vapor
- Water vapor released by plants and trees is referred to as transpiration.
Organic Matter
- Organic matter in water includes components such as wood, dogs, algae, and bacteria.
Water Treatment Processes
- Disinfection is identified as the single most crucial process in water treatment.
Nitrate Risks
- High nitrates in drinking water can lead to blue baby syndrome in infants.
Sanitary Control Easement
- Sanitary control easements must encompass land extending 150 feet around public water wells.
Well Sampling Protocol
- Samples for physical and chemical analysis from new wells should be collected after 36 hours of continuous pumping.
Chemical Analysis Frequency
- Chapter 290 Rules mandate annual chemical analyses for surface water supplies.
Sedimentation Basin Requirements
- Sedimentation basins must allow a minimum detention time of six hours for floc to settle effectively.
Filter Backwashing
- Backwashing filters should expand the filter media by 30% to 50%.
Chlorination Facilities
- All public water systems in Texas are required to have chlorination facilities for water treatment.
Trihalomethanes Standards
- The maximum contaminant level (MCL) for Trihalomethanes in drinking water is set at 0.080 mg/L.
Chlorine Characteristics
- At room temperature, chlorine gas is greenish-yellow and approximately 2.5 times heavier than air.
Waterborne Diseases
- Inadequately disinfected water can spread diseases such as typhoid, cholera, infectious hepatitis, and legionnaires' disease.
Chlorine Residuals
- Minimum chlorine residuals required in the distribution system are 0.2 mg/L for free chlorine and 0.5 mg/L for combined chlorine.
Coagulation Parameters
- Coagulation processes are influenced by turbidity, pH, alkalinity, the type of coagulant used, and its dosage.
Trench Safety Regulations
- Work is prohibited in trenches that are five feet deep or deeper unless they are properly protected from cave-ins.
Excavation Spoil Regulations
- Spoil banks must be placed at least two feet away from the edge of an excavation.
Chlorine Dosage for Water Mains
- New water mains must receive a minimum chlorine dosage of 25 mg/L for 24 hours, or 100 mg/L for 3 hours, or 500 mg/L for half an hour.
Bacteriological Sampling
- One bacteriological sample is required for every 1,000 feet of newly completed water main.
Cross Connection Definition
- A cross connection is a link between a public water supply and another supply of uncertain quality, any potential contamination source, or water treated to a lesser degree.
Ladder Spacing in Trenches
- The maximum distance between ladders in a trench is limited to 50 feet.
Sand Filter Backwashing Criteria
- Rapid sand filters should be backwashed when there is a head loss of 6 to 10 feet, or when filter NTU (Nephelometric Turbidity Units) reaches 1.0 or higher.
Pipe Bedding Calculation
- For a trench measuring 4 feet wide, 6 feet deep, and 1,000 feet long, approximately 86 cubic yards of pipe bedding is necessary for a depth of 7 inches.
Water Pipe Volume Calculation
- An 18-inch water pipe measuring 5,000 feet holds about 66,100 gallons of water.
Tank Disinfection Dosage
- To disinfect a 700,000-gallon tank with a chlorine dosage of 50 mg/L, around 449 pounds of 65% HTH would be required.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
Test your knowledge on essential water treatment concepts with these flashcards. Learn about water operator licensing in Texas, quality standards, and minerals that contribute to water hardness. Perfect for anyone interested in water utility management and regulations.
