CEPSCI Soil Science and Erosion Fundamentals

Question 1

What are the three types of soil particles, listed from largest to smallest?

Accepted Answer

Sand, silt, clay

Answer

Soil texture is determined by the relative proportions of sand (0.05–2 mm), silt (0.002–0.05 mm), and clay (<0.002 mm) particles.

Question 2

Which soil textural class is generally considered most erodible by water?

Accepted Answer

Silt and fine sand

Answer

Silt and fine sand particles are large enough to be detached by raindrop impact but small enough to be transported easily in runoff, making them highly erodible.

Question 3

What is 'raindrop splash erosion' (interrill erosion)?

Accepted Answer

Erosion caused by the impact of raindrops detaching soil particles and splashing them into suspension

Answer

Raindrop impact breaks up soil aggregates and detaches particles, making them available for transport by surface runoff — this is the first stage of water erosion.

Question 4

The Universal Soil Loss Equation (USLE) estimates:

Accepted Answer

Average annual soil loss from a field based on rainfall, soil erodibility, slope, cover, and management factors

Answer

The USLE combines the R (rainfall erosivity), K (soil erodibility), LS (slope length and steepness), C (cover and management), and P (support practice) factors to estimate erosion rates.

Question 5

What is soil compaction, and why is it a concern on construction sites from a stormwater perspective?

Accepted Answer

Compaction reduces soil porosity and infiltration capacity, increasing stormwater runoff volume

Answer

Heavy equipment compacts soil, reducing pore space and hydraulic conductivity, which means more rainfall becomes runoff rather than infiltrating — increasing erosion and stormwater discharge volumes.

CEPSCI - Certified Erosion Prevention and Sediment Control Inspector Practice Test

CEPSCI - Certified Erosion Prevention and Sediment Control Inspector Practice Test

CEPSCI Soil Science and Erosion Fundamentals