On this page
In this lesson
What you'll learn
- Tell routine maintenance apart from corrective action
- Apply the corrective action deadlines and logging rules
- Apply temporary stabilization deadlines based on disturbed area and receiving waters
- Know the final stabilization criteria needed to terminate coverage
Routine maintenance vs. corrective action
Not every problem is a corrective action. Under the EPA CGP:
- Routine maintenance keeps a working control working, such as removing sediment from a silt fence before it reaches half its height, or replacing a clogged inlet filter.
- Corrective action is required when (Part 5.1):
- A control needs a significant repair, or a new or replacement control is needed, or the same routine fix has been needed three or more times at the same location (unless documented as still routine);
- A required control was never installed or was installed incorrectly;
- Discharges are not meeting water quality standards;
- A prohibited discharge has occurred; or
- Dewatering triggers occur, such as a weekly average turbidity over 50 NTU or a visible plume or sheen.
Corrective action deadlines (Part 5.2)
For the first four triggers:
- Immediately take all reasonable steps to address the condition, including cleaning up contaminated surfaces so material won't discharge in later storms.
- If the fix doesn't need a new or replacement control or a significant repair, complete it by the close of the next business day.
- If it does need a new or replacement control or a significant repair, install or repair it and make it operational no later than 7 calendar days from discovery. If that's infeasible, document why and the schedule for completing it as soon as feasible.
- Update the SWPPP within 7 calendar days of completing work that changes controls or procedures.
The corrective action log (Part 5.4)
- Within 24 hours of identifying the condition: record the specific condition and the date and time it was found.
- Within 24 hours of completing the corrective action: record what was done and whether the SWPPP needs changes.
- Each entry is signed by the operator's signatory, kept on site or easily accessible, and retained 3 years.
Stabilization deadlines (Part 2.2.14)
Initiate stabilization immediately, meaning as soon as practicable but no later than the end of the next business day, in any area of exposed soil where construction has permanently ceased or will be temporarily inactive for 14 or more calendar days. Then complete it:
| Site condition | Complete stabilization within |
|---|---|
| 5 acres or less disturbed at any one time | 14 calendar days after initiating |
| More than 5 acres disturbed at any one time | 7 calendar days after initiating |
| Discharges to a sediment- or nutrient-impaired water, or a Tier 2, 2.5 or 3 water | 7 calendar days after initiating |
Stabilizing finished areas as you go "frees up" acreage, so a site can stay at or below the 5-acre cap and keep the 14-day deadline.
Final stabilization
To meet final stabilization for areas not covered by permanent structures, the CGP requires:
- Uniform, perennial vegetation, evenly distributed without large bare areas, providing 70 percent or more of the vegetative cover native to local undisturbed areas; and/or
- Permanent non-vegetative stabilization, such as riprap, gravel, gabions or geotextiles, providing effective cover.
Arid, semi-arid and drought-stricken areas have an alternative: seed or plant so that 70% of native cover will establish within 3 years, with temporary erosion controls as needed. Final stabilization is one of the conditions for filing the Notice of Termination; see lesson 3 and the closeout checklist.
Key takeaways
- Corrective action applies to significant repairs, new or replacement controls, repeat fixes, missing or wrong controls, water quality problems and prohibited discharges.
- Fix minor problems by the close of the next business day; new controls or significant repairs within 7 calendar days.
- Log the condition within 24 hours of finding it and the fix within 24 hours of completing it, signed.
- Start stabilization by the end of the next business day; finish in 14 days (5 acres or less at once) or 7 days (more than 5 acres, or sensitive waters).
- Final stabilization: 70% of native vegetative cover, or permanent non-vegetative cover.
Knowledge check
Lesson 10 quiz: 8 questions
Choose one answer for each question, then select Check my answers. Score 80% or higher to pass. Your answers stay in your browser and are never saved.
Sources and official references
Last reviewed: October 25, 2026 · Free general education based on the Clean Water Act, EPA NPDES rules and the EPA Construction General Permit. Your governing permit (EPA, state, tribal or local) controls. This is not legal advice, not EPA-approved, and not a California QSP/QSD or other state credential, and it does not issue a certificate. Nothing you enter on this page is saved or sent.