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SEPTIC INSTALLER TEST FOR
WASHINGTON STATE (WOSSA) PRACTICE
EXAM 2025 BRAND NEW ACTUAL EXAM
WITH 100% VERIFIED QUESTIONS AND
CORRECT SOLUTIONS| ACE YOUR
GRADES.
ANSI - correct answer -American National Standards Institute
BOD - correct answer -biochemical oxygen demand, typically
expressed in mg/L.
CBOD - correct answer -Carbonaceous Biochemical Oxygen
Demand, expressed in mg/L.
FC - correct answer -Fecal Coliform, expressed in number of
colonies 100/ml.
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LOSS - correct answer -large on-site sewage system
NSF - correct answer -Nation Sanitation Foundation International
O&G - correct answer -Oils and Grease, component of sewage
typically originating from food stuffs (animal fats of vegetable oils)
expressed in mg/L.
RS&G - correct answer -Recommended Standards and Guidance
SSAS - correct answer -a subsurface soil absorption system
TAC - correct answer -Technical Advisory Committee established
in WAC 247-272A-0400
TN - correct answer -Total Nitrogen, expressed in mg/L.
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TSS - correct answer -Total Suspended Solids. A measure of the
total suspended solids in a given solution, expressed in mg/L.
USEPA - correct answer -United States Environmental Protection
Agency
Additive - correct answer -a commercial product added to an on-
site sewage system intended to affect the performance or
aesthetics of an on-site sewage system
Approved - correct answer -Acceptable to the authority having
jurisdiction. Local health officer or the department
BED - correct answer -a soil dispersal component consisting of an
excavation with a width greater than 3 feet
Building Sewer - correct answer -that part of the horizontal piping
of a drainage system which starts from the end of the building
drain and which receives the discharge of the building drain and
conveys it to a public sewer, private sewer, individual sewage
disposal system or other point of disposal. It begins two feet
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outside the building wall and conveys sewage from the building
drain to the remaining portions of the on-site sewage system.
Cesspool - correct answer -a covered hole or pit for receiving
drainage or sewage, as from a house allowing liquid to seep into
the surronding rock or soil
Conforming System - correct answer -an on-site sewage system
of component meeting rules of: New construction requirements
Approved and installed within previous requirements
Permitted by WAC-246-272A-0420
Cover Material - correct answer -Soil placed over dispersal
component, made up of mineral material with no greater than
10% organic content. Cover may contain organic surface material,
an organic landscaper to help reduce and contain soil erosion.
Cuts and Banks - correct answer -a naturally occurring or
artificially formed slope greater than one hundred percent (forty-
five degrees) and extending vertically at least five from the toe of
the slope to top of the slope.
SEPTIC INSTALLER TEST FOR
WASHINGTON STATE (WOSSA) PRACTICE
EXAM 2025 BRAND NEW ACTUAL EXAM
WITH 100% VERIFIED QUESTIONS AND
CORRECT SOLUTIONS| ACE YOUR
GRADES.
ANSI - correct answer -American National Standards Institute
BOD - correct answer -biochemical oxygen demand, typically
expressed in mg/L.
CBOD - correct answer -Carbonaceous Biochemical Oxygen
Demand, expressed in mg/L.
FC - correct answer -Fecal Coliform, expressed in number of
colonies 100/ml.
, Page | 2
LOSS - correct answer -large on-site sewage system
NSF - correct answer -Nation Sanitation Foundation International
O&G - correct answer -Oils and Grease, component of sewage
typically originating from food stuffs (animal fats of vegetable oils)
expressed in mg/L.
RS&G - correct answer -Recommended Standards and Guidance
SSAS - correct answer -a subsurface soil absorption system
TAC - correct answer -Technical Advisory Committee established
in WAC 247-272A-0400
TN - correct answer -Total Nitrogen, expressed in mg/L.
, Page | 3
TSS - correct answer -Total Suspended Solids. A measure of the
total suspended solids in a given solution, expressed in mg/L.
USEPA - correct answer -United States Environmental Protection
Agency
Additive - correct answer -a commercial product added to an on-
site sewage system intended to affect the performance or
aesthetics of an on-site sewage system
Approved - correct answer -Acceptable to the authority having
jurisdiction. Local health officer or the department
BED - correct answer -a soil dispersal component consisting of an
excavation with a width greater than 3 feet
Building Sewer - correct answer -that part of the horizontal piping
of a drainage system which starts from the end of the building
drain and which receives the discharge of the building drain and
conveys it to a public sewer, private sewer, individual sewage
disposal system or other point of disposal. It begins two feet
, Page | 4
outside the building wall and conveys sewage from the building
drain to the remaining portions of the on-site sewage system.
Cesspool - correct answer -a covered hole or pit for receiving
drainage or sewage, as from a house allowing liquid to seep into
the surronding rock or soil
Conforming System - correct answer -an on-site sewage system
of component meeting rules of: New construction requirements
Approved and installed within previous requirements
Permitted by WAC-246-272A-0420
Cover Material - correct answer -Soil placed over dispersal
component, made up of mineral material with no greater than
10% organic content. Cover may contain organic surface material,
an organic landscaper to help reduce and contain soil erosion.
Cuts and Banks - correct answer -a naturally occurring or
artificially formed slope greater than one hundred percent (forty-
five degrees) and extending vertically at least five from the toe of
the slope to top of the slope.
