SEPTIC INSTALLER TEST FOR
WASHINGTON STATE (WOSSA)
PRACTICE EXAM 300 QUESTIONS
AND ALL COMPLETE SOLUTIONS.
"Distribution Technology - CORRECT ANSWER=> any arrangement of equipment and/or material that
distributes sewage within and on-site sewage system."
"Drainfield - CORRECT ANSWER=> subsurface soil absorption system, and soil dispersal component"
"Drainrock - CORRECT ANSWER=> cleaned washed gravel or crushed rock ranging in size from 3/4" to
2.5", and containing no more than two percent by weight passing a US No.8 sieve and no more than one
percent by weight passing through a US No. 200 Sieve."
"Effluent - CORRECT ANSWER=> liquid waste discharged to a septic tank or other on-site sewage
system"
"Expanding Clay - CORRECT ANSWER=> means a clay soil with the mineralogy of clay particles. Clay
particles expand when absorbing water"
"expansion - CORRECT ANSWER=> a change in residence, facility or site that results in the quantity of
sewage to exceed the original design"
"Extremely gravely - CORRECT ANSWER=> soils with 60% or more, but not less than 90% rock
fragments by volume."
"Failure - CORRECT ANSWER=> a condition of an on-site sewage component that threatens the public
health by inadequately treating the sewage, or creating a potential direct or indirect contact between
sewage and the public."
"Fecal coliform bacteria - CORRECT ANSWER=> bacteria found in the intestinal tracts of warm-blooded
animals that are cultured in standard tests. Generally expressed as colonies per 100 ml."
"Gravely - CORRECT ANSWER=> Soils with 15% or more, but less than 35% rock fragments by volume."
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,"Gray Water - CORRECT ANSWER=> Sewage from bathtubs, showers, bathroom sinks, kitchen sinks,
washing machines, and dishwashers."
"Ground water - CORRECT ANSWER=> Subsurface water in the zone of saturated soils, seasonally,
permanently, or as the result of the tides."
"Holding tank sewage system - CORRECT ANSWER=> an on-site sewage system that a holding tank with
no discharge outlet"
"hydraulic loading rate - CORRECT ANSWER=> the amount of effluent applied to a given treatment
step, expressed as gallons per square foot per day, (gal./sq.ft./day)"
"industrial waste - CORRECT ANSWER=> Waste from production of consumer goods, mining,
agriculture and petroleum extraction and refining"
"Infiltrative surface - CORRECT ANSWER=> Surface within a treatment component or soil dispersal
component to which effluent is applied and through which effluent moves into original, undisturbed soil
or other porous treatment media."
"Installer - CORRECT ANSWER=> a person approved by the local health office to install on-site sewage
systems or components"
"Local Health Officer - CORRECT ANSWER=> The provincial or municipal health officer."
"Maintenance - CORRECT ANSWER=> The actions necessary to keep the on-site sewage system
components functioning as designed"
"Massive structure - CORRECT ANSWER=> the condition of a soil layer in which the layer appears as a
coherent of solid mass not separated into peds of any kind"
"Moderated structure - CORRECT ANSWER=> Well- formed distinct peds evident in undisturbed soil.
When disturbed, soil material parts into mixture of whole peds, broken peds, and material that is not in
peds."
"Monitoring - CORRECT ANSWER=> Periodic or continuous surveillance of on-site sewage system,
which is performed by observations and measurements, to determine if the system is functioning as
intended and if system is in need of maintenance."
"On-site sewage system (OSS) - CORRECT ANSWER=> An integrated system of components , located on
or nearby the property it serves. that conveys, stores, treats, and/or provides subsurface soil treatment
and dispersal of sewage. It consists of a collection system, a treatment component or treatment
sequence, and a soil dispersal component."
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,"Operating capacity - CORRECT ANSWER=> the average daily volume of sewage an OSS can treat and
disperse on a sustained basis. The operating capacity, which is lower than design flow, is an integral part
of the design and is used as an index in OSS monitoring."
"Ordinary High Water Mark - CORRECT ANSWER=> The point on the bank or shore where water is
present often enough so that the upland begins to look different from the lake or stream bed."
"Ped - CORRECT ANSWER=> a unit of soil structure such as blocks, columns, granule, plate or prism
formed by natural process"
"Person - CORRECT ANSWER=> Any individual, partnership, corporation, association, government or
governmental subdivision or agency or other entity:"
"Planned Unit Development - CORRECT ANSWER=> A planned combination of diverse land uses, such
as housing, recreation, and shopping, in one contained development or subdivision."
"Platy structure - CORRECT ANSWER=> Thin, flat plates of soil that lie horizontally. Usually found in
compacted soil. This type of soil will impede the vertical movement of water."
"Pressure distribution - CORRECT ANSWER=> a system of small diameter pipes equally distributing
effluent throughout a SASS. Can include a drip system"
"Professional Engineer - CORRECT ANSWER=> A person who has passed the Fundamentals of
Engineering exam"
"Proprietary product - CORRECT ANSWER=> A sewage treatment, distribution technology, method, or,
material subject to patent or trademark"
"Public domain technology - CORRECT ANSWER=> a sewage treatment and distribution technology,
method, or material not subject to patent or trademark"
"Public sewage system - CORRECT ANSWER=> a sewage system owned by a public government"
"Pumper - CORRECT ANSWER=> a person approved by the local health officer to remove and transport
sewage or septage from on-site sewage systems"
"Record drawing - CORRECT ANSWER=> an accurate graphic and written record of the location and
features of the OSS that are needed to properly monitor, operate, and maintain that system."
"Repair - CORRECT ANSWER=> the relocation, replacement or reconstruction of a failed on-site sewage
system"
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, "Reserve area - CORRECT ANSWER=> an area of land approved for the installation of a conforming
system that is protected and maintained for replacement of the OSS upon its failure"
"Residential Sewage - CORRECT ANSWER=> sewage having the constituency and strength of typical
wastewater from a domestic home"
"Restrictive Layer - CORRECT ANSWER=> A compact, dense layer in a soil that impedes the movement
of water and the growth of roots."
"Rock fragments - CORRECT ANSWER=> Rock or mineral fragments having a diameter of 2 millimeters
or more; for example, pebbles, cobbles, stones, and boulders."
"Seepage pits - CORRECT ANSWER=> an excavation more than 3' deep where the sidewalls of the
excavation are designed to dispose septic tank effluent, also called "dry wells""
"Septage - CORRECT ANSWER=> the mixture of solid wastes, scum, sludge, and liquids pumped from
within septic tanks, pump chambers, holding tanks, and OSS components"
"Sewage - CORRECT ANSWER=> any urine, feces, and the water carrying human wastes, including
kitchen, bath, and laundry wastes from residences, buildings, industrial establishments or other places."
"Sewage quality - CORRECT ANSWER=> contents in sewage that include: CBOD5, TSS, and O&G, PH,
temperature and dissolved oxygen,"
"Sewage Tank - CORRECT ANSWER=> a prefabricated or cast- in- place septic tank/dosing chamber,
holding tank, grease interceptor, recirculating filter tank or any other tanks as they relate to on-site
sewage systems including tanks for use with proprietary pruducts"
"Soil dispersal component - CORRECT ANSWER=> a technology that releases effluent from a treatment
component into the soil dispersal , final treatment and recycling"
"Soil log - CORRECT ANSWER=> a detailed description of soil characteristics providing information on
the soils capacity to act as an acceptable treatment and dispersal medium for sewage"
"Soil scientist - CORRECT ANSWER=> a persons certified by the American Society of Agronomy as a
Certified Soil Scientist"
"Soil type - CORRECT ANSWER=> one of seven numerical classifications of fine earth particles and rock
fragments as described in WAC 246-272A-0220 (2)(e)"
"Strong structure - CORRECT ANSWER=> peds are distinct in undisturbed soil. They separate cleanly
when soil is disturbed, and the soil material separates mainly into peds when removed,"
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WASHINGTON STATE (WOSSA)
PRACTICE EXAM 300 QUESTIONS
AND ALL COMPLETE SOLUTIONS.
"Distribution Technology - CORRECT ANSWER=> any arrangement of equipment and/or material that
distributes sewage within and on-site sewage system."
"Drainfield - CORRECT ANSWER=> subsurface soil absorption system, and soil dispersal component"
"Drainrock - CORRECT ANSWER=> cleaned washed gravel or crushed rock ranging in size from 3/4" to
2.5", and containing no more than two percent by weight passing a US No.8 sieve and no more than one
percent by weight passing through a US No. 200 Sieve."
"Effluent - CORRECT ANSWER=> liquid waste discharged to a septic tank or other on-site sewage
system"
"Expanding Clay - CORRECT ANSWER=> means a clay soil with the mineralogy of clay particles. Clay
particles expand when absorbing water"
"expansion - CORRECT ANSWER=> a change in residence, facility or site that results in the quantity of
sewage to exceed the original design"
"Extremely gravely - CORRECT ANSWER=> soils with 60% or more, but not less than 90% rock
fragments by volume."
"Failure - CORRECT ANSWER=> a condition of an on-site sewage component that threatens the public
health by inadequately treating the sewage, or creating a potential direct or indirect contact between
sewage and the public."
"Fecal coliform bacteria - CORRECT ANSWER=> bacteria found in the intestinal tracts of warm-blooded
animals that are cultured in standard tests. Generally expressed as colonies per 100 ml."
"Gravely - CORRECT ANSWER=> Soils with 15% or more, but less than 35% rock fragments by volume."
Page | 1
,"Gray Water - CORRECT ANSWER=> Sewage from bathtubs, showers, bathroom sinks, kitchen sinks,
washing machines, and dishwashers."
"Ground water - CORRECT ANSWER=> Subsurface water in the zone of saturated soils, seasonally,
permanently, or as the result of the tides."
"Holding tank sewage system - CORRECT ANSWER=> an on-site sewage system that a holding tank with
no discharge outlet"
"hydraulic loading rate - CORRECT ANSWER=> the amount of effluent applied to a given treatment
step, expressed as gallons per square foot per day, (gal./sq.ft./day)"
"industrial waste - CORRECT ANSWER=> Waste from production of consumer goods, mining,
agriculture and petroleum extraction and refining"
"Infiltrative surface - CORRECT ANSWER=> Surface within a treatment component or soil dispersal
component to which effluent is applied and through which effluent moves into original, undisturbed soil
or other porous treatment media."
"Installer - CORRECT ANSWER=> a person approved by the local health office to install on-site sewage
systems or components"
"Local Health Officer - CORRECT ANSWER=> The provincial or municipal health officer."
"Maintenance - CORRECT ANSWER=> The actions necessary to keep the on-site sewage system
components functioning as designed"
"Massive structure - CORRECT ANSWER=> the condition of a soil layer in which the layer appears as a
coherent of solid mass not separated into peds of any kind"
"Moderated structure - CORRECT ANSWER=> Well- formed distinct peds evident in undisturbed soil.
When disturbed, soil material parts into mixture of whole peds, broken peds, and material that is not in
peds."
"Monitoring - CORRECT ANSWER=> Periodic or continuous surveillance of on-site sewage system,
which is performed by observations and measurements, to determine if the system is functioning as
intended and if system is in need of maintenance."
"On-site sewage system (OSS) - CORRECT ANSWER=> An integrated system of components , located on
or nearby the property it serves. that conveys, stores, treats, and/or provides subsurface soil treatment
and dispersal of sewage. It consists of a collection system, a treatment component or treatment
sequence, and a soil dispersal component."
Page | 2
,"Operating capacity - CORRECT ANSWER=> the average daily volume of sewage an OSS can treat and
disperse on a sustained basis. The operating capacity, which is lower than design flow, is an integral part
of the design and is used as an index in OSS monitoring."
"Ordinary High Water Mark - CORRECT ANSWER=> The point on the bank or shore where water is
present often enough so that the upland begins to look different from the lake or stream bed."
"Ped - CORRECT ANSWER=> a unit of soil structure such as blocks, columns, granule, plate or prism
formed by natural process"
"Person - CORRECT ANSWER=> Any individual, partnership, corporation, association, government or
governmental subdivision or agency or other entity:"
"Planned Unit Development - CORRECT ANSWER=> A planned combination of diverse land uses, such
as housing, recreation, and shopping, in one contained development or subdivision."
"Platy structure - CORRECT ANSWER=> Thin, flat plates of soil that lie horizontally. Usually found in
compacted soil. This type of soil will impede the vertical movement of water."
"Pressure distribution - CORRECT ANSWER=> a system of small diameter pipes equally distributing
effluent throughout a SASS. Can include a drip system"
"Professional Engineer - CORRECT ANSWER=> A person who has passed the Fundamentals of
Engineering exam"
"Proprietary product - CORRECT ANSWER=> A sewage treatment, distribution technology, method, or,
material subject to patent or trademark"
"Public domain technology - CORRECT ANSWER=> a sewage treatment and distribution technology,
method, or material not subject to patent or trademark"
"Public sewage system - CORRECT ANSWER=> a sewage system owned by a public government"
"Pumper - CORRECT ANSWER=> a person approved by the local health officer to remove and transport
sewage or septage from on-site sewage systems"
"Record drawing - CORRECT ANSWER=> an accurate graphic and written record of the location and
features of the OSS that are needed to properly monitor, operate, and maintain that system."
"Repair - CORRECT ANSWER=> the relocation, replacement or reconstruction of a failed on-site sewage
system"
Page | 3
, "Reserve area - CORRECT ANSWER=> an area of land approved for the installation of a conforming
system that is protected and maintained for replacement of the OSS upon its failure"
"Residential Sewage - CORRECT ANSWER=> sewage having the constituency and strength of typical
wastewater from a domestic home"
"Restrictive Layer - CORRECT ANSWER=> A compact, dense layer in a soil that impedes the movement
of water and the growth of roots."
"Rock fragments - CORRECT ANSWER=> Rock or mineral fragments having a diameter of 2 millimeters
or more; for example, pebbles, cobbles, stones, and boulders."
"Seepage pits - CORRECT ANSWER=> an excavation more than 3' deep where the sidewalls of the
excavation are designed to dispose septic tank effluent, also called "dry wells""
"Septage - CORRECT ANSWER=> the mixture of solid wastes, scum, sludge, and liquids pumped from
within septic tanks, pump chambers, holding tanks, and OSS components"
"Sewage - CORRECT ANSWER=> any urine, feces, and the water carrying human wastes, including
kitchen, bath, and laundry wastes from residences, buildings, industrial establishments or other places."
"Sewage quality - CORRECT ANSWER=> contents in sewage that include: CBOD5, TSS, and O&G, PH,
temperature and dissolved oxygen,"
"Sewage Tank - CORRECT ANSWER=> a prefabricated or cast- in- place septic tank/dosing chamber,
holding tank, grease interceptor, recirculating filter tank or any other tanks as they relate to on-site
sewage systems including tanks for use with proprietary pruducts"
"Soil dispersal component - CORRECT ANSWER=> a technology that releases effluent from a treatment
component into the soil dispersal , final treatment and recycling"
"Soil log - CORRECT ANSWER=> a detailed description of soil characteristics providing information on
the soils capacity to act as an acceptable treatment and dispersal medium for sewage"
"Soil scientist - CORRECT ANSWER=> a persons certified by the American Society of Agronomy as a
Certified Soil Scientist"
"Soil type - CORRECT ANSWER=> one of seven numerical classifications of fine earth particles and rock
fragments as described in WAC 246-272A-0220 (2)(e)"
"Strong structure - CORRECT ANSWER=> peds are distinct in undisturbed soil. They separate cleanly
when soil is disturbed, and the soil material separates mainly into peds when removed,"
Page | 4
