CSM Erosion & Sediment Control Flashcards

What is the primary purpose of a silt fence installed at a construction site?

Answer: To intercept sediment-laden runoff and allow sediment to settle before water leaves the site

A silt fence is a temporary sediment control device that intercepts sheet flow runoff, slowing it down so suspended sediment can settle out before the water leaves the site.

Which temporary erosion control practice is most appropriate for stabilizing steep disturbed slopes during construction?

Answer: Hydroseeding with tackifier

Hydroseeding with a tackifier bonds mulch and seed to steep slopes, providing immediate surface protection while vegetation establishes.

What is the function of a sediment basin on a construction site?

Answer: To collect and detain runoff so sediment can settle before discharge

A sediment basin temporarily impounds runoff from disturbed areas, allowing suspended sediment to settle before the clarified water is discharged.

According to best practice, when should temporary erosion and sediment controls be installed on a construction site?

Answer: Before or simultaneously with land disturbance activities

Temporary controls must be in place before or at the time land is disturbed to prevent erosion and off-site sediment discharge from the very start of grading.

What is the primary purpose of installing check dams in a drainage channel or swale?

Answer: To reduce flow velocity and allow sediment to deposit upstream of the dam

Check dams slow channel flow velocity, reducing erosive energy and causing suspended sediment to settle in the pool formed upstream.

Which material is most commonly used as a stabilized construction entrance to reduce tracking of mud onto public roads?

Answer: Crushed stone or gravel pad

A stabilized construction entrance uses crushed stone or aggregate over geotextile fabric to knock mud off vehicle tires as they leave the site, preventing sediment tracking onto roads.