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  • What is the minimum inside diameter for access points in risers for aerobic treatment plans?
  • How do you size sanitary dump stations for RVs with a disposal system?
  • How high should the riser be above ground surface for proper functioning of a pump chamber?
  • What is the primary consideration for sizing a subsurface seepage system for Class I effluent?
  • All gravelless drainfield pipes must be encased with what feature at the point of manufacture?
  • Who specifies the number of drip emitters per linear foot in a drip irrigation system?
  • When gravelless and chamber systems are installed, they are required to be looped or what?
  • What precedes a wetland seepage pond (WSP)?
  • Which of the following describes the required characteristics of chlorine tanks?
  • What factors determine the pressure requirements for a drip irrigation system?
  • When is it not necessary to loop the ends of a gravel distribution system?
  • What flow rate adjustment is needed for a commercial building with a sand filter of 1000 GPD?
  • What is the minimum size of a solids retention tank for kitchen waste?
  • How far away must distribution lines be from the sidewalls of a seepage bed?
  • What is the minimum number of doses required in a time dosing system over a 24-hour period?
  • What material is specified for the top layer over sand media in a sand filter?
  • Who is authorized to perform the excavation for a septic system installation?
  • What is the purpose of the check valve in a septic system?
  • What is the maximum BOD allowed per gallon per day in a commercial building for sand filter sizing?
  • How should a commercial building sand filter system be sized?
  • What is the primary function of a baffle in a chlorine tank?
  • What pipe schedule is acceptable for installation under roads or driveways?
  • How much larger does the bottom of a seepage bed need to be compared to what is determined by the soil chart?
  • Under what condition is a check valve allowed between the pump and the piping network?
  • What is one type of connector allowed between trenches in a serial distribution system?
  • Hourly flows from the wastewater source into a commercial ATU should be less than or equal to what parameter?
  • What is the primary purpose of the dosing volume in a septic system?
  • How do you size the dosing tank for homes with more than three bedrooms or non-residential buildings?
  • What is the sidewall sizing ratio for raised filter beds?
  • What is the maximum distance allowed for a quick disconnect from a device?
  • What is the minimum spacing requirement for holes in gravelless piping?
  • What is the spacing between the two rows of holes in collection lines?
  • Service for aerobic treatment units (ATUs) should be arranged within how many working days following a request?
  • How much freeboard must be provided above the water line in a WSP?
  • When should the first maintenance of a septic tank after installation for a residence be completed?
  • What is an acceptable material for piping in a septic system?
  • How do you size a sand filter for a residence?
  • Does a drip irrigation system require a filter?
  • True or False: Gravelless seepage systems must have a specific type of separation material placed prior to backfill.
  • What size uniformly spaced perforations are acceptable for 8" gravelless pipe?
  • What is the acceptable slope tolerance for the bottom of a raised filter bed mantle?
  • In gravelless piping, holes must be staggered such that there is at least one hole in each corrugation. True or False?
  • What is the purpose of having a screen on the vent in a sand filter?
  • What kind of materials can be used for separation in a gravel system?
  • What baffle can be used as an outlet in a WSP?
  • What is the general purpose of time dosing in drip irrigation systems?
  • How is the pump shut-off controlled in a recirculating SF system?
  • For how long should a homeowner keep maintenance records of their septic system?
  • What is one of the options for using a garbage grinder with a private sewage disposal system?
  • For drip irrigation systems, how is the flow rate through each emitter determined?
  • What is the required diameter for the sewer line of a sanitary dump station?
  • Can fill soils be used with a Dis?
  • What is a crucial aspect of the drip emitter specification?
  • What is the minimum vertical separation required from the bottom of drip tubing to a limiting layer?
  • What are the requirements for satisfactory fill soils in a DIS?
  • Which feature must be included to connect adjacent trenches in a serial distribution system?
  • When must a private residence connect to a public sewer system?
  • What is the required percolation test standard for a DIS?
  • Are embankments required to be constructed from impermeable compacted material?
  • Where does the air relief valve go in a DIS?
  • Where should the pressure gauge be installed in a DIS?
  • What is the minimum depth of earth backfill required over a serial system?
  • What is the recommended capacity of the pump for a recirculating SF?
  • In a functioning septic system, what role does the pump play?
  • What aspect determines the design flow for sizing a tank in a private sewage system with a garbage grinder?
  • True or False: The bedding material for the collection lines in a recirculating sand filter is the same as in a regular sand filter.
  • Seepage beds must be how many times larger than determined by soil analysis?
  • What can backwash water from sand filters be discharged into?
  • What is the function of collection lines in a recirculating sand filter (SF)?
  • What method should be used to prevent freezing of a Drip Irrigation System (DIS)?
  • What height should the curb surrounding a sanitary dump station's concrete pad be?
  • By how much can you reduce the square footage of a sand filter if it is preceded by an ATU?
  • What is the minimum required treatment capacity in gallons per day for residences with 1-10 bedrooms?
  • What slope should collection lines in a sand filter have?
  • What should be placed over the sand media in a sand filter?
  • In a multiple compartment tank, what is the requirement for the first compartment's capacity?
  • What is the maximum center-to-center spacing allowed for seepage beds?
  • What is the minimum tank size required for sewage flows up to 500 gallons per day?
  • What is the recommended slope for a concrete pad for a sanitary dump station?
  • When can siphons be designed in relation to a sand filter and siphon chamber?
  • When sizing the tank for a raised filter bed in a commercial building, what is the required aeration tank size?
  • The invert of the first relief line must be at least how many inches lower than the invert of the septic tank outlet?
  • What must be done to the exposed surface of an embankment?
  • What is the required bedding material for gravelless seepage and chamber systems?
  • If the flow is greater than 801 GPD for a non-residence sand filter, what is required?
  • What is the maintenance schedule for a DIS?
  • What is the minimum required service contract to be provided by the contractor after installation of an ATU?
  • How are the head requirements for a dosing pump determined?
  • What is the maximum recirculation rate designed for a flow splitter in a recirculating SF?
  • Can a drip irrigation system surface discharge?
  • What is the minimum radius that 8" or 10" gravelless pipe should be bent around?
  • Which component is crucial for indicating high water levels in a pump chamber?
  • Why does a distributed irrigation system (DIS) need air reliefs?
  • What should the spacing be for openings in perforated pipe used in gravel systems?
  • What is the minimum contact tank capacity for chlorine tanks?
  • How much longer should the length of DI tubing be compared to its width?
  • What is the minimum trench width for a gravel system?
  • What is the purpose of a foot-operated self-closing cap at a sanitary dump drain?
  • True or False: 8"-10" inside diameter polyethylene tubing must meet ASTM F667-06 standards.
  • If flows are greater than 500 gallons per day, how should the septic tank size be determined?
  • What must a seepage bed be at least 6 inches away from?
  • What happens if the riser is not adequately elevated above ground?
  • When a WSP is preceded by a septic tank, how is it sized?
  • Which method of discharge is NOT allowed for Class II effluent from aerobic systems?
  • What guidelines dictate the installation and maintenance of aerobic treatment units?
  • In which formation cannot a septic system be installed if the bottom is less than 4 feet from the top of the limestone?
  • What is a primary function of an aerobic treatment unit?
  • What is the required depth of the sand filter media in a recirculating sand filter?
  • What is the appropriate material to cover the distribution line in a gravel system?
  • Does a DIS require a chemical injection port?
  • What is the maximum allowable vertical to horizontal slope ratio for embankments above the water line?
  • What is the minimum depth of sand filter media for a buried sand filter?
  • What is the minimum diameter for a riser in the pump chamber after a sand filter if gravity flow is not possible?
  • How wide should the top of an embankment be at minimum?
  • For commercial buildings or residences with flows exceeding 1500 gpd, what filter loading rate should be applied?
  • How far must the sewer line maintain separation from the water line?
  • What spacing should distribution lines be set on in a recirculating sand filter?
  • What is the recommended depth of a wetland seepage pond?
  • When should a septic system for a non-residential building be initially evaluated after installation?
  • When should the high-water (HW) alarm activate?
  • How deep must the mantle of a raised filter bed be placed into the original soil?
  • How do you ensure proper maintenance of an aerobic treatment unit?
  • What is the dimension of fill soil beneath the tracks in site preparation?
  • Which of the following types of systems can have effluent discharges?
  • The siphon must deliver the same flow rate as what system?
  • Which type of distribution lines can be used in gravel systems?
  • How should the perforations in collection lines be oriented?
  • What type of alarm control device is commonly used for a DIS?
  • What should be the condition of soil above bedrock for a DIS?
  • What minimum slope is recommended for a discharge from WSP in inches per feet?
  • Effluent discharges to the ground surface are limited to how many discharges per acre?
  • How far should the concrete pad for a sanitary dump station extend around the drain?
  • In commercial ATUs, what percentage of the rated hydraulic capacity must total daily flows be at least?
  • What should the setting of a sealed float or diaphragm switch be in relation to the pump turn-on level?
  • What should the slope of the embankment be below the water line in a WSP?
  • What is the minimum daily flow a sand filter shall be based on?
  • What is the requirement for installation of a septic system when a physical barrier or ordinance exists?
  • How do you determine the size of a recirculating sand filter?
  • How far away must inlets discharge from the water's edge in a WSP?
  • What is one requirement for the installation of a gravelless seepage system regarding extraneous materials?
  • What is one requirement for alternative media in a buried sand filter?
  • What type of pipe is used for distribution lines in raised filter beds?
  • How many experimental systems must be installed before unconditional approval is granted?
  • What is essential for maintaining the filter in a drip irrigation system?
  • What is the implication of having a high-water alarm malfunction?
  • True or False: A gravelless seepage system must have separation material placed before backfill.
  • In a private sewage disposal system, how should the garbage grinder waste be handled?
  • In what incremental distance must distribution lines be set for raised filter beds?
  • What is the minimum slope required for a 4" pipe in a gravity system?
  • What is the required tank size for a raised filter bed in a residential setting?
  • Maximum fill soil usage in a DIS is limited to what depth?
  • Which design feature must be present to ensure the outlet baffle functions correctly?
  • When should pumping of a septic tank be conducted?
  • What is the required distance for the inlets of a Water Surface Profile (WSP) from the bottom?
  • What is the minimum amount of backfill required above the gravel system in this setup?
  • What is the center-to-center spacing for a gravel system with an 8"-24" trench width?
  • What is the recommended depth for DI tubing installation?
  • What consequence results if a shorter bending radius is required for gravelless pipe?
  • What should be done if allowed to split flows for sand filters?
  • The design of a raised filter bed mantle should not exceed what percolation rate?
  • How often should aerobic treatment units be evaluated?
  • How should the soil be treated before using fill?
  • What type of pump is used in a dosing system for drip irrigation?
  • Where does a peat filter system typically discharge effluent?
  • What is the minimum capacity required for a dosing tank in a drip irrigation system?
  • Which scenario describes a common collector for effluent discharge systems?
  • What is the minimum thickness of coarse gravel that must be placed before collection lines in a sand filter?
  • What is the minimum dosing volume required in relation to the pipe volume of the dosing network?
  • What type of material should be used as the bedding for a gravel system?
  • In a gravel trench, what is the minimum and maximum depth?
  • How far must distribution lines in a sand filter be from sidewalls?
  • Who is allowed to evaluate an aerobic treatment unit?
  • What is the maintenance schedule for septic filters and wastewater systems with surface discharges?
  • Which professional is NOT allowed to evaluate a septic system for a non-residential building?
  • Under what condition should a serial distribution system be used?
  • What is the purpose of having a high level float switch in the pump system?
  • A recirculating sand filter consists of which components?
  • How far must distribution lines be from sidewalls in seepage beds and sand filters?
  • What is the recommended depth for sand filter media in a raised filter bed?
  • Distribution lines in a sand filter should be spaced at what distance?
  • What is the minimum diameter for pipes used in a gravel system?
  • Which systems can precede a peat filter system?
  • How should a septic tank be sized if receiving all flows?
  • What is the requirement for venting in a sand filter system?
  • What is the designated minimum distance of undisturbed earth between the septic tank and the nearest trench in a serial distribution system?
  • What is the minimum depth of sand filter media required for a sand filter?
  • How should the site be prepared for the use of fill in a DIS?
  • Where should flush valves be located in a DIS?
  • How can the dosage volume impact the septic system's efficiency?
  • What is a valid reason for approving a holding tank?
  • What is the maximum size allowed for a raised filter bed?
  • True or False: A buried sand filter must have a surface area of 2 gallons per square foot per day and can be dosed up to four times per day following an aerobic treatment plant.
  • How is access for a DIS system different from other systems?
  • Is it required for the high-water alarm to be on a separate circuit than the pump?
  • How long is an experimental use permit valid for?
  • True or False: The length of a WSP should exceed three times its width.
  • In a serial distribution system, the relief pipe must connect with the higher trench's top at what level?
  • When is splitting flows prior to treatment by a sand filter permitted?
  • What is the maximum trench width for a gravel system?
  • What is the appropriate diameter for distribution lines in a recirculating SF?
  • What type of system is needed for a non-residence with flow greater than 801 GPD?
  • How much can the size of a subsurface system be reduced if it meets the effluent requirements?
  • What is the total depth consideration for the torpedo sand in a raised filter bed?
  • Class I effluent for aerobic systems shall discharge to which option?
  • What is required if the sludge layer or suspended solids in a septic tank exceeds 33%?
  • What is the acceptable final effluent free chlorine residual range?
  • What is the minimum center-to-center spacing required for an 18" chamber system?
  • In a holding tank scenario, which of the following is NOT a valid purpose?
  • What must a recirculation tank have if it contains a pump?
  • Which material can support backfill in a gravel system?
  • Where should backwash water be directed in a DIS?
  • How many times a day should a dosing system typically dose a sand filter in a commercial building scenario?
  • What is required if a sand filter is designed for a non-residential property with a flow of 801 gpd or more?
  • When should cleanouts be installed in a building sewer?
  • True or False: Seepage beds must meet the same requirements as gravel seepage systems.
  • What should be done if limestone is known to be present during a soil test?
  • Is pretreatment necessary for a drip irrigation system?
  • In gravelless systems, the pipe must be marked to indicate what?
  • What is essential to ensure when installing a serial distribution system to facilitate flow between trenches?
  • What filter loading rate should be used for sizing raised filter beds for residences with up to 1500 gpd?
  • Why is it important for the pump circuit and alarm circuit to be separate?
  • A raised filter bed mantle must be at least equal to what area?
  • How is backwash from sand filters categorized?
  • How should a drip irrigation system be sized according to soil characteristics?
  • What must be done if a building is more than 300 feet from a sewer line and has flow less than 1500 gpd?
  • What is the maximum spacing for distribution lines in a seepage bed?
  • What is the minimum requirement for the aeration tank size in a series of tanks for flow equalization?
  • Can a homeowner install and maintain a septic system on their own property?
  • What size must a recirculation tank be?
  • For flows greater than 1350 gallons per day, what is the proper method for sizing tanks?
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