OSSF DR Exam 2025 Preparation Guide With 200
Questions and Correct Answers | TX OSSF Designated
Representative Test Latest 2025-2026 Practice Questions
with 100% Correct Answers (Brand New!)
List the OSSF licenses that require previous experience - ANSWER-installer II,
Site evaluator (SE), and Maintenance Provider (MP)
The _______ is responsible for reviewing permit applications, site evaluations,
planning materials, and conducting inspections of OSSFs - ANSWER-DR
(designated representative)
_______ adopted the current OSSF Rules in 1997 and revised them several times -
ANSWER-TCEQ
An individual who holds a valid license from the TCEQ and who is compensated
by another individual to construct, install, alter, or repair an OSSF is a(n)
_________. - ANSWER-installer
Class II soils include the USDA classes of _________ and __________. -
ANSWER-sandy loam, loam
The _________ is a tool to graphically delineate soil textural classes. - ANSWER-
USDA soil textural triangle
List the two unsuitable types of soil structure or structural condition. - ANSWER-
Platy (like a stack of plates)
Massive ( can't break it up, huge pieces)
pg. 1
,A soil color pattern of orange and brown on a background of gray or bluish color is
called - ANSWER-mottling
The ideal soil environment for organic effluent decomposition is one of good
______ and ________. - ANSWER-soil air, soil water balance
Soil associations are _______ units which encompass broad areas with similar
patterns of __________, __________, __________, and _________. - ANSWER-
soil. soil profiles, vegetation, relief, and drainage
The county ____________________ is an essential tool for conducting a site
evaluation but does not take the place of the on-site field soil evaluation. -
ANSWER-soil survey
Sites with greater than ____ percent slope are unsuitable. - ANSWER-30
A minimum lot size of _______ acre is required for subdivisions serviced by
_________ water. The minimum size is ______ acre for those serviced by
___________. - ANSWER-0.5, public, 1, private well
Soil evaluation pits shall be excavated to a depth of _____ inches below the
proposed _________ or to a _________ horizon, whichever is shallower. -
ANSWER-24, drainfield, restrictive
Any soil profile with an indication of high-water table within _____ inches below
the proposed drainfield shall be considered _____________ for a standard
drainfield. - ANSWER-24, unsuitable
pg. 2
,The ___________ and ____________ of each soil horizon should be measured
from ________ to _________ and recorded in the soil evaluation report. -
ANSWER-sequence, depth, top, bottom
The depth of soil classified as suitable with respect to texture shall be at least ____
inches below the bottom of the proposed excavation for a standard drainfield. -
ANSWER-24
If a soil with no gravel will not form a ribbon in the texture-by-feel method, it is
classified as ______ or ______, class ____. - ANSWER-sand or loamy sand, Ib
If a soil forms a ribbon greater than 2 inches, and neither smooth or gritty
consistency predominates, the soil is _______, class _____. - ANSWER-clay, IV
Soil suitability factors include: _________, ________, and _________. -
ANSWER-soil texture, soil depth, and restrictive horizon
Overall site suitability factors include ________, ________, ___________, and
____________. - ANSWER-site factor, soil factors, groundwater evaluation, and
surface drainage analysis
A common reason for wastewater system failure is __________. - ANSWER-
hydraulic overloading (due to modernized tank usually)
The value Q is - ANSWER-Quantity of Sewage (GPD)
Some malfunctioning OSSF can be made to function properly with minimal cost
by implementing ______________. - ANSWER-water conservation measures.
pg. 3
, In estimating water usage for a single-family dwelling, the number of _________
in the home is a key indicator; however, _________ should also be considered. -
ANSWER-bedrooms, square footage
List four water saving plumbing devices that can be used in a home. - ANSWER-
low flow toilets, low flow shower head, low flow faucets, pressure reducing valves
Identify four water-saving habits homeowners should adopt - ANSWER-don't
leave water running, full laundry and dishwasher loads, reduce/eliminate use of
garbage disposals, not using toilet for trash disposal
Two wastewater tests commonly used to measure the strength of sewage are the
________ test and the ________ test. - ANSWER-BOD, TSS
The minimum water usage rate that should be used for planning an OSSF for a new
home with three bedrooms and 3000 square feet of interior living area is _______
gallons/day. - ANSWER-300
Blockage in the home plumbing system is often caused by _______, ________,
and _________. - ANSWER-oils, greases, and fats
It is recommended that _____________ are not used because they significantly
increase the amount of suspended solids and organic matter that is discharged to
sewage disposal system. - ANSWER-garbage disposal
Several samples were taken from a small washateria with seven new water-
conserving machines and sent to a lab for BOD analysis. The average BOD was
406 mg/L. What would be the minimum expected BOD (organic) loading in
lbs./day? - ANSWER-4.74 lbs/day
pg. 4
Questions and Correct Answers | TX OSSF Designated
Representative Test Latest 2025-2026 Practice Questions
with 100% Correct Answers (Brand New!)
List the OSSF licenses that require previous experience - ANSWER-installer II,
Site evaluator (SE), and Maintenance Provider (MP)
The _______ is responsible for reviewing permit applications, site evaluations,
planning materials, and conducting inspections of OSSFs - ANSWER-DR
(designated representative)
_______ adopted the current OSSF Rules in 1997 and revised them several times -
ANSWER-TCEQ
An individual who holds a valid license from the TCEQ and who is compensated
by another individual to construct, install, alter, or repair an OSSF is a(n)
_________. - ANSWER-installer
Class II soils include the USDA classes of _________ and __________. -
ANSWER-sandy loam, loam
The _________ is a tool to graphically delineate soil textural classes. - ANSWER-
USDA soil textural triangle
List the two unsuitable types of soil structure or structural condition. - ANSWER-
Platy (like a stack of plates)
Massive ( can't break it up, huge pieces)
pg. 1
,A soil color pattern of orange and brown on a background of gray or bluish color is
called - ANSWER-mottling
The ideal soil environment for organic effluent decomposition is one of good
______ and ________. - ANSWER-soil air, soil water balance
Soil associations are _______ units which encompass broad areas with similar
patterns of __________, __________, __________, and _________. - ANSWER-
soil. soil profiles, vegetation, relief, and drainage
The county ____________________ is an essential tool for conducting a site
evaluation but does not take the place of the on-site field soil evaluation. -
ANSWER-soil survey
Sites with greater than ____ percent slope are unsuitable. - ANSWER-30
A minimum lot size of _______ acre is required for subdivisions serviced by
_________ water. The minimum size is ______ acre for those serviced by
___________. - ANSWER-0.5, public, 1, private well
Soil evaluation pits shall be excavated to a depth of _____ inches below the
proposed _________ or to a _________ horizon, whichever is shallower. -
ANSWER-24, drainfield, restrictive
Any soil profile with an indication of high-water table within _____ inches below
the proposed drainfield shall be considered _____________ for a standard
drainfield. - ANSWER-24, unsuitable
pg. 2
,The ___________ and ____________ of each soil horizon should be measured
from ________ to _________ and recorded in the soil evaluation report. -
ANSWER-sequence, depth, top, bottom
The depth of soil classified as suitable with respect to texture shall be at least ____
inches below the bottom of the proposed excavation for a standard drainfield. -
ANSWER-24
If a soil with no gravel will not form a ribbon in the texture-by-feel method, it is
classified as ______ or ______, class ____. - ANSWER-sand or loamy sand, Ib
If a soil forms a ribbon greater than 2 inches, and neither smooth or gritty
consistency predominates, the soil is _______, class _____. - ANSWER-clay, IV
Soil suitability factors include: _________, ________, and _________. -
ANSWER-soil texture, soil depth, and restrictive horizon
Overall site suitability factors include ________, ________, ___________, and
____________. - ANSWER-site factor, soil factors, groundwater evaluation, and
surface drainage analysis
A common reason for wastewater system failure is __________. - ANSWER-
hydraulic overloading (due to modernized tank usually)
The value Q is - ANSWER-Quantity of Sewage (GPD)
Some malfunctioning OSSF can be made to function properly with minimal cost
by implementing ______________. - ANSWER-water conservation measures.
pg. 3
, In estimating water usage for a single-family dwelling, the number of _________
in the home is a key indicator; however, _________ should also be considered. -
ANSWER-bedrooms, square footage
List four water saving plumbing devices that can be used in a home. - ANSWER-
low flow toilets, low flow shower head, low flow faucets, pressure reducing valves
Identify four water-saving habits homeowners should adopt - ANSWER-don't
leave water running, full laundry and dishwasher loads, reduce/eliminate use of
garbage disposals, not using toilet for trash disposal
Two wastewater tests commonly used to measure the strength of sewage are the
________ test and the ________ test. - ANSWER-BOD, TSS
The minimum water usage rate that should be used for planning an OSSF for a new
home with three bedrooms and 3000 square feet of interior living area is _______
gallons/day. - ANSWER-300
Blockage in the home plumbing system is often caused by _______, ________,
and _________. - ANSWER-oils, greases, and fats
It is recommended that _____________ are not used because they significantly
increase the amount of suspended solids and organic matter that is discharged to
sewage disposal system. - ANSWER-garbage disposal
Several samples were taken from a small washateria with seven new water-
conserving machines and sent to a lab for BOD analysis. The average BOD was
406 mg/L. What would be the minimum expected BOD (organic) loading in
lbs./day? - ANSWER-4.74 lbs/day
pg. 4
