OSSF DR STUDY GUIDE 2026 COMPLETE
QUESTIONS WITH SOLUTIONS GRADED A+
◉ List each of the major soil horizons. Answer: 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.. Answer: Hydraulic conductivity, saturated, unsaturated
◉ Interconnected pores in the soil profile allow ______ and _______ to
enter the soil at its surface and migrate downward. Answer: air, water
◉ List the four components of soil. Answer: 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)? Answer:
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? Answer: 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? Answer: 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.. Answer: 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? Answer: 846 gals
◉ Calculate the working liquid capacity (volume) for this septic tank.
SEE PAGE 2-39!!. Answer: 1077gals
◉ What is the surface area (area in square feet) of an evapotranspiration
system 40 feet wide and 65 feet long? Answer: 2,600 sqft
◉ Figure the acreage for a piece of property that measures 256 feet on
each of four sides.. Answer: 1.5 acres
◉ Figure the area of a lot that measures 60ft by 280ft. Answer:
16,800sqft ,0.39 acres
, ◉ A disposal option that might be considered in a clay soil would be a
________.. Answer: drip or spray irrigation
◉ The primary treatment device providing the least or poorest treatment
of domestic wastewater would be _______.. Answer: septic tank
◉ Nitrogen or nitrate removal in soil occurs by _________.. Answer:
vegetation uptake
◉ The factors influencing the survival of bacteria in soil are _______..
Answer: moisture, temperature, pH, and organic matter.
◉ Physical removal of bacteria by straining occurs when _______..
Answer: the bacteria are larger than the pore openings in the soil
◉ A solid that can be filtered out of the wastewater is a _________..
Answer: suspended solid
◉ Which of the following describes domestic wastewater as it leaves a
home? Answer: fresh, light in color, has dissolved oxygen
◉ Which of the following are problems caused by malfunctioning septic
tank systems? Answer: surface water pollution, groundwater
contamination, and standing sewage in neighborhoods
QUESTIONS WITH SOLUTIONS GRADED A+
◉ List each of the major soil horizons. Answer: 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.. Answer: Hydraulic conductivity, saturated, unsaturated
◉ Interconnected pores in the soil profile allow ______ and _______ to
enter the soil at its surface and migrate downward. Answer: air, water
◉ List the four components of soil. Answer: 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)? Answer:
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? Answer: 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? Answer: 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.. Answer: 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? Answer: 846 gals
◉ Calculate the working liquid capacity (volume) for this septic tank.
SEE PAGE 2-39!!. Answer: 1077gals
◉ What is the surface area (area in square feet) of an evapotranspiration
system 40 feet wide and 65 feet long? Answer: 2,600 sqft
◉ Figure the acreage for a piece of property that measures 256 feet on
each of four sides.. Answer: 1.5 acres
◉ Figure the area of a lot that measures 60ft by 280ft. Answer:
16,800sqft ,0.39 acres
, ◉ A disposal option that might be considered in a clay soil would be a
________.. Answer: drip or spray irrigation
◉ The primary treatment device providing the least or poorest treatment
of domestic wastewater would be _______.. Answer: septic tank
◉ Nitrogen or nitrate removal in soil occurs by _________.. Answer:
vegetation uptake
◉ The factors influencing the survival of bacteria in soil are _______..
Answer: moisture, temperature, pH, and organic matter.
◉ Physical removal of bacteria by straining occurs when _______..
Answer: the bacteria are larger than the pore openings in the soil
◉ A solid that can be filtered out of the wastewater is a _________..
Answer: suspended solid
◉ Which of the following describes domestic wastewater as it leaves a
home? Answer: fresh, light in color, has dissolved oxygen
◉ Which of the following are problems caused by malfunctioning septic
tank systems? Answer: surface water pollution, groundwater
contamination, and standing sewage in neighborhoods
