OSSF DR TEST PRACTICE STUDY GUIDE LATEST 2026 UPDATED
QUESTIONS AND VERIFIED 100% SOLUTIONS (2026/2027)
GRADE: A+|STATUS: GUARANTEED PASS
Any soil profile with an indication of high-water table within _____ inches below the proposed
drainfield shall be considered _____________ for a standard drainfield. - Answers -24,
unsuitable
The ___________ and ____________ of each soil horizon should be measured from ________
to _________ and recorded in the soil evaluation report. - Answers -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. - Answers -24
If a soil with no gravel will not form a ribbon in the texture-by-feel method, it is classified as
______ or ______, class ____. - Answers -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 _____. - Answers -clay, IV
Soil suitability factors include: _________, ________, and _________. - Answers -soil texture,
soil depth, and restrictive horizon
1|Page
,Overall site suitability factors include ________, ________, ___________, and ____________. -
Answers -site factor, soil factors, groundwater evaluation, and surface drainage analysis
A common reason for wastewater system failure is __________. - Answers -hydraulic
overloading (due to modernized tank usually)
The value Q is - Answers -Quantity of Sewage (GPD)
Some malfunctioning OSSF can be made to function properly with minimal cost by
implementing ______________. - Answers -water conservation measures.
In estimating water usage for a single-family dwelling, the number of _________ in the home is
a key indicator; however, _________ should also be considered. - Answers -bedrooms, square
footage
List four water saving plumbing devices that can be used in a home. - Answers -low flow toilets,
low flow shower head, low flow faucets, pressure reducing valves
Identify four water-saving habits homeowners should adopt - Answers -don't leave water
running, full laundry and dishwasher loads, reduce/eliminate use of garbage disposals, not using
toilet for trash disposal
2|Page
, Two wastewater tests commonly used to measure the strength of sewage are the ________ test
and the ________ test. - Answers -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. - Answers -
300
Blockage in the home plumbing system is often caused by _______, ________, and _________. -
Answers -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. -
Answers -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? - Answers -4.74 lbs/day
Would a treatment plant capable of handling 1500 gallons per day of wastewater with BOD as
high as 280 mg/L be capable of handling wastewater from the above washateria? What is the
organic loading capacity of this treatment plant? - Answers -3.50 lbs/day
3|Page
QUESTIONS AND VERIFIED 100% SOLUTIONS (2026/2027)
GRADE: A+|STATUS: GUARANTEED PASS
Any soil profile with an indication of high-water table within _____ inches below the proposed
drainfield shall be considered _____________ for a standard drainfield. - Answers -24,
unsuitable
The ___________ and ____________ of each soil horizon should be measured from ________
to _________ and recorded in the soil evaluation report. - Answers -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. - Answers -24
If a soil with no gravel will not form a ribbon in the texture-by-feel method, it is classified as
______ or ______, class ____. - Answers -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 _____. - Answers -clay, IV
Soil suitability factors include: _________, ________, and _________. - Answers -soil texture,
soil depth, and restrictive horizon
1|Page
,Overall site suitability factors include ________, ________, ___________, and ____________. -
Answers -site factor, soil factors, groundwater evaluation, and surface drainage analysis
A common reason for wastewater system failure is __________. - Answers -hydraulic
overloading (due to modernized tank usually)
The value Q is - Answers -Quantity of Sewage (GPD)
Some malfunctioning OSSF can be made to function properly with minimal cost by
implementing ______________. - Answers -water conservation measures.
In estimating water usage for a single-family dwelling, the number of _________ in the home is
a key indicator; however, _________ should also be considered. - Answers -bedrooms, square
footage
List four water saving plumbing devices that can be used in a home. - Answers -low flow toilets,
low flow shower head, low flow faucets, pressure reducing valves
Identify four water-saving habits homeowners should adopt - Answers -don't leave water
running, full laundry and dishwasher loads, reduce/eliminate use of garbage disposals, not using
toilet for trash disposal
2|Page
, Two wastewater tests commonly used to measure the strength of sewage are the ________ test
and the ________ test. - Answers -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. - Answers -
300
Blockage in the home plumbing system is often caused by _______, ________, and _________. -
Answers -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. -
Answers -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? - Answers -4.74 lbs/day
Would a treatment plant capable of handling 1500 gallons per day of wastewater with BOD as
high as 280 mg/L be capable of handling wastewater from the above washateria? What is the
organic loading capacity of this treatment plant? - Answers -3.50 lbs/day
3|Page
