Practice Test Geeks(CESSWI) Certified Erosion, Sediment, and Storm Water Inspector Practice Test
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Erosion & Sediment Control Principles Flashcards

7 cards from real CESSWI practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.

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  1. A construction SWPPP must be updated when which of the following occurs?

    Answer: Site conditions change in a way that affects stormwater discharges

    NPDES Construction General Permits require SWPPP amendments whenever there are changes in design, construction, operation, or maintenance that affect the potential for pollutant discharges.

  2. Which factor most directly determines the settling velocity of a sediment particle in a quiescent (still) water environment?

    Answer: Particle size, density, and shape

    Settling velocity in still water is governed by Stokes' Law, which relates particle diameter, density, and shape to the rate at which a particle sinks.

  3. A slope with a 3:1 (horizontal:vertical) gradient is considered what relative to erosion risk compared to a 4:1 slope?

    Answer: Higher risk because a 3:1 slope is steeper than a 4:1 slope

    A 3:1 slope is steeper than a 4:1 slope (33% vs. 25% grade), resulting in higher flow velocities and greater erosion potential.

  4. What is the most common cause of silt fence failure in the field?

    Answer: Concentrated flow overtopping or breaching the fence at low points

    Silt fences most commonly fail when runoff concentrates and overtops or flows around the ends of the fence at topographic low points rather than as sheet flow.

  5. During final stabilization inspection, what minimum percentage of vegetative cover is typically required before a CGP Notice of Termination (NOT) can be submitted?

    Answer: 70%

    EPA's Construction General Permit defines final stabilization as achieving 70% vegetative cover density compared to pre-disturbance conditions, or equivalent permanent stabilization.

  6. An inspector observes that a rock outlet protection apron at the end of a pipe is missing several stones, exposing bare soil. What is the primary risk of this condition?

    Answer: Scour erosion at the pipe outlet that can undermine the pipe and headwall

    Missing outlet protection exposes the soil below and downstream of the pipe to high-velocity discharge, causing scour that can progressively undermine structural components.

  7. Which of the following scenarios would require the installation of a temporary diversion dike above a disturbed area?

    Answer: Runoff from undisturbed upland areas drains across an active construction zone

    Temporary diversion dikes intercept clean runoff from upland areas before it crosses disturbed ground, preventing it from picking up sediment and complicating stormwater management.