TCEQ Class C Water Operator License Exam - Q & A To be classified as a pws, the system must have at least __ service connections or serve at least __
... [Show More] individuals at least ___ days out of the year. 15, 25, 60 Concentrations of fluoride greater than (>) ___mg.L can cause ____ in teeth over time. 2, mottling Low doses of heavy metals, such as lead and copper, can cause damage to the ______ _____ ______ over time. central nervous system The action level for lead is ____mg.L, and for copper is ____mg/L. 0.015, 1.3 One by-product of chlorinated water is ____________, a suspected carcinogen when consumed in water over a lifetime. Trihalomethane Chlorine is combined with ______ to form chloramines to prevent the formation of _._._._. in surface water. ammonia, thms Supply systems must maintain a minimum water pressure of ___ psi under normal conditions and at least ___psi during emergencies. 35, 20 Service tap components usually consist of a tapping saddle, corporation stop, service line tubing, curb stop and a _____. Meter If a repaired main line must be returned to service quickly, dose it with ____mg/L Chlorine, for ___minutes. 500, 30 The 2 primary categories of pumps are: ____ and _____. centrifugal, positive displacement The "Texas Hazard Communications Act" is known as the "____ ___ ____ Act." right to know _____ all shoring from the top down and _____ from the bottom up. install, remove Out of all the water on earth, less than _____% of freshwater is immediately available to humans. 1 The term associated with water that evaporates from living plants is referred to as _____. Evapotranspiration _____% of all the water on earth is saltwater. 97 Bacti sample bottles are prepared with a chemical called _____ before they are sterilized. sodium thiosulfate Killing disease causing organisms in the water is the primary purpose of ____ in water mains. Disinfection Liquefied chlorine gas will expand ____ times its original volume. 460 Chlorine gas is ____ times heavier than breathing air. 2.5 Chlorine gas is considered to be ____% pure. 100 Bleach is approximately _____% pure. 5.25 HTH dry powder chlorine is set at ____% purity. 65 A commonly used method to test for chlorine residual in water is called the ____ method. Dpd When chlorine gas is added to water, the pH goes down due to the two _____ that form. Acids Water with a pH of 7.9 is considered to be ______ or _____. basic, alkaline [Show Less]