OSSF DR TEST PRACTICE Exam fully solved &
updated 2025-2026(latest version verified for
accuracy) (Questions + Answers) Solved 100%
Correct
_______ and ________ soil textural classes are always
unsuitable for standard absorptive OSSF
class IA and IV
List each of the major soil horizons
surface soil A, surface soil B, and parent material
_____________ is a term describing the ability of water to
migrate through a soil profile under either _________ or
__________ conditions.
Hydraulic conductivity, saturated, unsaturated
Interconnected pores in the soil profile allow ______ and
_______ to enter the soil at its surface and migrate downward
air, water
List the four components of soil
air, water, organics, inorganics
A drainfield is 50 feet by 90 feet and must be covered with an
average of 15 inches of sand loam. How many cubic yards of
sandy loam soil must be purchased (find the volume of a
rectangular object)?
208.3 cubic yards
What would be the volume of a 5-foot-diameter pump tank
that is 5 feet tall with the inlet 1 foot below the rim?
587 gals
,What would be the percent slope on a lot 250 feet deep that
drops 20 feet in elevation over the depth of the lot?
8%
How many cubic yards of gravel would be needed to fill a
ditch 3 feet deep, 10 feet wide, and 12 feet long with 18
inches of gravel? 1 cubic yard = 27 cubic feet.
6.67 cubic yards
A septic tank is 6 feet in diameter and is 8 feet deep. How
many gallons will it hold if the overflow line is located half
way up from the bottom?
846 gals
Calculate the working liquid capacity (volume) for this septic
tank. SEE PAGE 2-39!!
1077gals
What is the surface area (area in square feet) of an
evapotranspiration system 40 feet wide and 65 feet long?
2,600 sqft
Figure the acreage for a piece of property that measures 256
feet on each of four sides.
1.5 acres
Figure the area of a lot that measures 60ft by 280ft
16,800sqft ,0.39 acres
A disposal option that might be considered in a clay soil
would be a ________.
drip or spray irrigation
The primary treatment device providing the least or poorest
treatment of domestic wastewater would be _______.
septic tank
Nitrogen or nitrate removal in soil occurs by _________.
vegetation uptake
, The factors influencing the survival of bacteria in soil are
_______.
moisture, temperature, pH, and organic matter.
Physical removal of bacteria by straining occurs when
_______.
the bacteria are larger than the pore openings in the soil
A solid that can be filtered out of the wastewater is a
_________.
suspended solid
Which of the following describes domestic wastewater as it
leaves a home?
fresh, light in color, has dissolved oxygen
Which of the following are problems caused by
malfunctioning septic tank systems?
surface water pollution, groundwater contamination, and standing
sewage in neighborhoods
An inorganic chemical that affects human health is
nitrate
Parasites (helminths) found in untreated sewage include
________.
hookworm, round worms, and tapeworms
Viruses are responsible for such diseases as
poliomyelitis and infectious hepatitis
A type of bacteria that indicates sewage contamination is
________.
fecal coliform
Protozoa are very simple animal organisms that may cause
________.
amoeba dysentery and Giardiasis
Waterborne diseases that spread by pathogenic bacteria
include _________.
updated 2025-2026(latest version verified for
accuracy) (Questions + Answers) Solved 100%
Correct
_______ and ________ soil textural classes are always
unsuitable for standard absorptive OSSF
class IA and IV
List each of the major soil horizons
surface soil A, surface soil B, and parent material
_____________ is a term describing the ability of water to
migrate through a soil profile under either _________ or
__________ conditions.
Hydraulic conductivity, saturated, unsaturated
Interconnected pores in the soil profile allow ______ and
_______ to enter the soil at its surface and migrate downward
air, water
List the four components of soil
air, water, organics, inorganics
A drainfield is 50 feet by 90 feet and must be covered with an
average of 15 inches of sand loam. How many cubic yards of
sandy loam soil must be purchased (find the volume of a
rectangular object)?
208.3 cubic yards
What would be the volume of a 5-foot-diameter pump tank
that is 5 feet tall with the inlet 1 foot below the rim?
587 gals
,What would be the percent slope on a lot 250 feet deep that
drops 20 feet in elevation over the depth of the lot?
8%
How many cubic yards of gravel would be needed to fill a
ditch 3 feet deep, 10 feet wide, and 12 feet long with 18
inches of gravel? 1 cubic yard = 27 cubic feet.
6.67 cubic yards
A septic tank is 6 feet in diameter and is 8 feet deep. How
many gallons will it hold if the overflow line is located half
way up from the bottom?
846 gals
Calculate the working liquid capacity (volume) for this septic
tank. SEE PAGE 2-39!!
1077gals
What is the surface area (area in square feet) of an
evapotranspiration system 40 feet wide and 65 feet long?
2,600 sqft
Figure the acreage for a piece of property that measures 256
feet on each of four sides.
1.5 acres
Figure the area of a lot that measures 60ft by 280ft
16,800sqft ,0.39 acres
A disposal option that might be considered in a clay soil
would be a ________.
drip or spray irrigation
The primary treatment device providing the least or poorest
treatment of domestic wastewater would be _______.
septic tank
Nitrogen or nitrate removal in soil occurs by _________.
vegetation uptake
, The factors influencing the survival of bacteria in soil are
_______.
moisture, temperature, pH, and organic matter.
Physical removal of bacteria by straining occurs when
_______.
the bacteria are larger than the pore openings in the soil
A solid that can be filtered out of the wastewater is a
_________.
suspended solid
Which of the following describes domestic wastewater as it
leaves a home?
fresh, light in color, has dissolved oxygen
Which of the following are problems caused by
malfunctioning septic tank systems?
surface water pollution, groundwater contamination, and standing
sewage in neighborhoods
An inorganic chemical that affects human health is
nitrate
Parasites (helminths) found in untreated sewage include
________.
hookworm, round worms, and tapeworms
Viruses are responsible for such diseases as
poliomyelitis and infectious hepatitis
A type of bacteria that indicates sewage contamination is
________.
fecal coliform
Protozoa are very simple animal organisms that may cause
________.
amoeba dysentery and Giardiasis
Waterborne diseases that spread by pathogenic bacteria
include _________.
