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Commercial Septic System Installer
Exam
The sizing of grease traps should take into consideration the ___________________ and the ___________________________________. - โ
โ type of facility served and the
estimated daily sewage flow.
Grease traps may be constructed of ___________materials used for conventional septic tanks. - โ โ any
It is recommended that grease traps be cleaned when ___________ percent of their grease retention capacity is reached. - โ โ 75%
Commercial on-site sewage disposal systems shall adhere to all the standards established for residential systems unless __________________________________. - โ โ specifically addressed in the permit.
Commercial systems shall be sized according to the ______________________________________ for the facility to be served. - โ โ anticipated daily sewage flow
For residential type facilities both single and multifamily, _________________ per bedroom will be used to estimate the number of gallons per day sewage flow. - โ โ 150 gallons per bedroom
Where garbage grinders are used increase tank capacity by __________________% - โ โ 50%
All solid pipe used in the installation of on-site sewage disposal systems shall be schedule _________________ or equivalent. (cast Iron shall be considered to meet the equivalency standard.) - โ โ 40 PVC
All wiring and electrical components for systems requiring electrical components should for systems requiring electrical components should meet the standards set forth in the ____________________________________. - โ โ National Electrical Code
Trenches that exceed sixty inches in depth should have ___________ stabilized with appropriate shoring devices. - โ โ Walls
How can a Septic tank be reinforced? - โ โ six inch by 6 inch (6"x6") No. gage welded steel reinforcing wire OR fibrous reinforcing material conforming to ASTM specifications for such materials.
How must Tank Lids be Reinforced? - โ โ using three-eights steel reinforcing rods (rebar) which shall be spaced twelve inches (12") on center each way extending a minimum of two and one half (2 1/2") inches and a maximum of three (3") from the outside edge of the tank lid.
In general, the tank must be able to withstand a uniform live load of ______________________ pounds per square foot in addition to all loads to which an underground tank is normally subjected. - โ โ 150
True or False: Walls, bottoms, and lids of poured-in-place septic tanks should have a minimum thickness of four inches (4"). - โ โ True
Tank lids shall be constructed in ______________________ pieces and shall have securable, removable access openings located so that the inlet and outlet tees can be ________________________________. - โ โ one or two,
readily accessed.
Access opening shall have a minimum of _________________ and maximum of ___________________ free space. - โ โ Minimum: 15"
Maximum: 24"
Tanks with more than 12 inches of cover must extend access openings to within ______ inches of the ground surface. - โ โ 12
All tanks shall be equipped with ________________________________ rated or equivalent tees at the inlet and outlet ends of the tank. - โ โ Four inch (4") PVC, ASTM 3034
Tees shall be constructed so they extend into the liquid a minimum of ____________________ and a maximum of __________________ of the liquid depth of the tank. - โ โ Min: 25%
Max: 50%
The invert of the outlet tee shall be located _______________ inches below the invert of the inlet tee. - โ โ two inches
__________________ tees shall be equipped with an approved effluent filter. - โ โ Outlet
Dosing can be accomplished using _____________ or _______________. - โ โ pumps or siphons.
Systems requiring at least five hundred (500') but less than one thousand (1000') linear feet of field line will need _____________. - โ โ a single pump or siphon.
Systems requiring one thousand linear feet (1000') or more will need ________________________________. - โ โ alternating pumps or siphons.
True or False: Dosing tanks shall meet the construction requirements for septic tanks with regard to construction materials and reinforcement. - โ โ True
True or False: For dosing tanks One or two piece tanks may be used. - โ โ True
When two piece Dosing tanks are used sections must be _______________by using mastic, butyl rubber, or other pliable sealant that is water proof, corrosion resistant and approved for use in septic tanks. - โ โ Joined
For Dosing tanks, there shall be no requirement as to _____________,_____________,or ___________ of tank. - โ โ length, width, of shape
Tanks may have a single compartment or if a partition is used it must have _______________________________________ located no more than ________inches above the tank bottom. - โ โ 2 four inch diameter holes or equivalent,
12 inches
Dosing tanks using PUMPS must have a reserve capacity of _______________ flow. - โ โ One days
True or False: Dosing tanks for SIPHONS will not be required to have one days flow reserved. - โ โ True
True or False: All tanks must have an operating liquid capacity of 60%-70% the interior volume of the absorption lines to be dosed. - โ โ True
All dosing tanks shall have switches and alarms that notify the owner of _____________________. - โ โ malfunction.
When determining dosing tank requirements _____________, _________________, _________________, and ____________________ should be taken into consideration. - โ โ volume, flow rates, waste water characteristics, and other similar information
When field lines are above the elevation of the operating water level of the tank, a _______________________ should be used to prevent the contents of discharge pipes from emptying back into the tank. - โ โ check valve
When field lines are below the elevation of the operating water level of the tank, a ________________________ should be placed in the discharge pipe before it exits the tank to prevent siphoning the remaining contents of the tanks after the pump shuts off. - โ โ hole or other vacuum breaking device
_____________ are the non-mechanical alternative to pumps. - โ โ Siphons
How do Siphons work? - โ โ As the dosing tank fills, head pressure increases in the tank to a point that will force the effluent through the siphon which is a specially designed trap, creating suction in the discharge line that empties the contents of the dosing tank to the level of the siphon bell and sniff hole. Equilibrium is then re-established in the line until the water level rises again to the level that the process starts all over again.
As with pumps, single siphons are used for systems with more than ______ linear feet of field line and alternating siphons are used for systems with more than _______ linear feet of field line. - โ โ 500, (single)
1000, (alternating)
When installing siphons, care should be taken to assure they are installed ____________ and are _____________________________ - โ โ level and are primed with water.
Grease traps are required for any installation where the amount of grease in the effluent stream exceeds _____________ milligrams per liter - โ โ 50 mg/l
Grease traps are rarely used for homes. Their main application is in treating _____________ waste waters from motels, cafeterias, restaurants, hospitals, schools and other institutions with large volumes of kitchen wastewater. - โ โ Kitchen
True or False: The purpose of the grease trap is to the grease from the other water carried waste which will protect the pipes in the system from clogging the soil. - โ โ True
True or False: Effluent from the grease trap is deposited in the septic tank along with the other water carried waste from the facility. - โ โ True
In Georgia the minimum sized grease trap allowable is __________________ gallons. - โ โ 125 gallons.
