Stormwater & Environmental
Earthwork exposes bare soil, so keeping sediment out of storm drains and creeks is a core C-12 responsibility — and part of the exam’s safety/environmental section.
When you need permit coverage
A site disturbing 1 acre or more (or part of a larger common plan) needs coverage under California’s Construction General Permit (Order 2022-0057-DWQ, effective Sept 1, 2023). The SWPPP is prepared by a QSD and implemented by a QSP.
Coverage is obtained by filing permit registration documents — including a Notice of Intent and the SWPPP — through the State Water Board’s SMARTS system. Sites are assigned a Risk Level (1, 2, or 3) based on sediment and receiving-water risk, with more monitoring at higher levels.
Erosion control vs sediment control
The exam tests the distinction:
- Erosion control stops soil from detaching — hydroseeding, mulch, erosion-control blankets, preserving vegetation. (The first line of defense.)
- Sediment control captures detached soil before it leaves the site — silt fences, fiber rolls, sediment basins, inlet protection, a stabilized construction entrance. (The last line of defense.)
Good housekeeping — managing materials, waste, concrete washout, and spills — keeps other pollutants out of runoff.
Practice: Stormwater & Environmental
Frequently asked
When does a construction site need a stormwater permit in California?
What is the difference between erosion control and sediment control?
Who prepares and implements the SWPPP?
More C-12 Earthwork & Paving topics
Planning & Estimating Earthwork
C-12 study guide on planning and estimating earthwork: reading plans, cut and fill, balancing a site, shrink and swell factors, percent grade, and project layout.
Read & practice →Soils & Compaction
C-12 study guide on soils and compaction: the Proctor test, maximum dry density, optimum moisture content, relative compaction, standard vs modified Proctor, and lifts.
Read & practice →Excavation & Grading
C-12 study guide on excavation and grading: the pavement structure (subgrade, subbase, base course), load distribution, benching fill into slopes, grade control, and trench backfill.
Read & practice →Paving & ADA
C-12 study guide on paving: asphalt vs concrete pavement, prime and tack coats, base failure causes, concrete joints, and ADA slope limits for ramps, parking, and cross slope.
Read & practice →Excavation Safety (OSHA)
C-12 study guide on OSHA trench and excavation safety: when a protective system is required, soil types and slopes, the competent person, access and egress, spoil placement, water, and atmospheres.
Read & practice →Work-Zone Traffic Control
C-12 study guide on work-zone traffic control for paving and roadway jobs: orange signs, taper length, the flagger's STOP/SLOW paddle, and channelizing device spacing.
Read & practice →