Flashcards › The A water Exam Question Part 1

What is the name of the State Agency for enforcing the Safe Drinking Water Program in Texas? TECQ (Texas Commission on Environmental Quality What minerals cause water hardness? Calcium & Magnesium A public water system must at all times provide- Adequate (quantity,pressure,Disinfection) A source of ground water Aquifer Fecal Coliform organisms found in water supplies are an indication that- water is contminated,harmful bacteria may be pesent,possible pathogen,and water is unsuitable for drinking A disease that may be spread by inadequately disinfected water- Dysentery A common chemical used in disinfection of water is - Calcium Hypochlorite A physical connection between a potable water supply and a house well - A Cross Connection The amount of Chlorine in mg/L that is used up by reacting with iron , organics,or bacterica is- Demand Physical characteristic of Chlorine Gas are Greenish yellow color, heavier than air, pugent/penetrating ordor, & Corrosive What would be considered a part of a hydro-chlorinator system Solution feed pump All public water wells should have a raised concrete sealing block,& Screened vents and flow measuring device The drawdown of a water well is determined by - The difference in the static and pumping levels The pH of Water indicates--- Acidic or Base The pH scale is 0-14 Neutral on the pH scale is 7.0 One of the step in collecting a distribution sample for Bacteriological testing is An approved sterile sample container Sand filtration will remove what from surface water- Turbidity Activated Carbon is used in surface water plants to remove Taste and Odors Ground storage tanks are required to provide - Screened vents, locking roof hatchs, overflow pipe with hinged flap & inspection annually An elevated storage tank procted by- Painting, Cathodic protection, water stabilization A public must maintain a residual pressure of- 20 psi A minimum normal operating pressure would be 35 psi What is the proper disinfection dosage for new or repaired water line and proper detention time? 50mg/L for 24Hr. A water bearing fomation under the ground that is used for public water supply are- Aquifers What dose a air line do on a water well- Determine water levels in the well The mesh size is important in a well screen because- It can reduce the amount of sand pumed Treating surface water, the process of coagulation will be most affected by pH,alkalinity, temp., & chemical dosage A rapid sand filter should be backwashed when- The loss of head gauge indicated between 6 and 10 ft. What is an acceptable disinfection residual at the end of a distribution system? 1). 0.2 mg/L freechlorine, 2). 0.5 chloramine for a surface water supply 3). 0.8 chloramine when using chloramine treatment 4). 0.5 free chlorine for groundwater What is the approx. volume of a cirular tank in gallons, 30ft in dia., and 15ft deep. Approx. 80,000 (.785 x D x D x ht x 7.58) To provide a dosage of 4.0 mg/L -the daily usage is 750,000 gallons, the gas chlorinator feed rat should be set at- 25 pounds per day (do the math) One gallon of water weighs- 8.34 lbs one foot of water will raise a pressure gauge --- .433 lbs A raw water intake can not be with in _____ft of a boat ramp, dock or marina 1000 ft Two common types of pumps used in water wells are-- Vertical Turbine & Submersible The natural exchange of water between the earth and air is Hydrological Cycle When a health contamination event occurs in a public water system, the state must be contact by phone within ___hrs. 24hrs Potable water is pathogen free,adequate pressure, contains a chlorine residual Excessive nitrates in drinking water affects infants under 6 month is known as- blue babies surface water process causing the fine particles to join together to form larger that settle is called Coagulation Commonly used test to determine the chemical dosage for a surface water plant is Jar test Suspended solids are the solids portion that cause-- Mudballs & filter plugging water samples take for bacteriogical ananalysis uses what organism as a indicator-- Coliform Chlorine dosage is demand plus desired ________. Residual A storagevessel with the same diameter from ground to top and 20ft but less than 80ft tall is called Stand pipe Water must be elevated at least 80.85ft above the highest connection to provide the min. operating pressure of --- 35 psi A water tank that uses compress air over water to provide pressure is -- Hydro pneumatic tank Pipes and fitting may not contain more than _____ lead. 8% Solder and flux may not contain more than ____ lead. 2% This is prep. for taking the A water exam for the State of Texas