Construction Site Best Management Practices Flashcards

A stabilized construction entrance is designed to:

Answer: Remove mud and debris from vehicle tires to prevent tracking onto public roads

A stabilized construction entrance made of coarse aggregate scrapes mud and debris from vehicle tires before they exit the site, preventing sediment tracking onto adjacent paved roads and storm drain inlets.

What is the recommended aggregate size for a stabilized construction entrance?

Answer: Coarse aggregate 1.5 to 3 inches in diameter

Coarse aggregate in the 1.5 to 3 inch range is large enough to knock mud off tires through mechanical agitation as vehicles drive over it, while remaining stable under heavy equipment loads.

Inlet protection BMPs are installed at storm drain inlets to:

Answer: Prevent sediment-laden runoff from entering the storm drain system and being conveyed directly to receiving waters

Inlet protection devices such as sediment traps, filter bags, or curb inlet protection prevent sediment from entering storm drains and being transported directly to streams or other receiving waters.

What is the purpose of a concrete washout area on a construction site?

Answer: To contain wash water and concrete waste from concrete trucks and equipment, preventing discharge to the stormwater system

Concrete washout areas contain highly alkaline concrete wash water and residual concrete, preventing it from entering storm drains or waterways where it could cause significant water quality impacts.

Which BMP is most effective for controlling erosion on a steep slope that cannot be immediately seeded?

Answer: Erosion control blanket or turf reinforcement mat installed on the slope surface

Erosion control blankets or turf reinforcement mats physically protect the soil surface on steep slopes from raindrop impact and runoff erosion, providing interim stabilization until vegetation establishes.

A pipe slope drain is used to:

Answer: Convey runoff down a steep slope in a controlled manner without causing erosion

A pipe slope drain transports concentrated runoff down steep slopes through a pipe to a protected outlet, preventing erosion that would occur if water flowed freely down the slope surface.