OSSF DESIGNATED REPRESENTATIVE EXAM
2025-2026 QUESTIONS AND ANSWERS GRADED
A+
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
,_______ 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
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
2025-2026 QUESTIONS AND ANSWERS GRADED
A+
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
,_______ 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
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
