How should turbidity be evaluated on-site, and what action should be taken if turbidity levels exceed thresholds?

How should turbidity be evaluated on-site, and what action should be taken if turbidity levels exceed thresholds?

• A. By visual observations and/or turbidity measurements per permit; if exceedances occur, enhance BMPs, remove sediment, and document corrective actions.
• B. Only through laboratory turbidity tests, with no visual assessment.
• C. Turbidity is not monitored on-site.
• D. Only turbidity in surface waters is of concern; on-site turbidity can be ignored.

Answer: (D)

Turbidity on-site is a live signal of how well sediment controls are functioning, so you evaluate it using both visual observations and field or permit-based turbidity measurements. If turbidity levels exceed what the permit allows, you should promptly strengthen sediment controls (enhance BMPs), remove accumulated sediment from disturbed areas or drainage paths, and thoroughly document the corrective actions taken and any follow-up monitoring. This approach provides real-time information to prevent polluted runoff from leaving the site and supports compliance requirements. Relying only on laboratory tests misses those real-time conditions, and ignoring on-site turbidity is not acceptable because it can indicate problems before they affect receiving waters. Turbidity in surface waters matters, but monitoring on-site turbidity is essential to protect them.

Turbidity on-site is a live signal of how well sediment controls are functioning, so you evaluate it using both visual observations and field or permit-based turbidity measurements. If turbidity levels exceed what the permit allows, you should promptly strengthen sediment controls (enhance BMPs), remove accumulated sediment from disturbed areas or drainage paths, and thoroughly document the corrective actions taken and any follow-up monitoring. This approach provides real-time information to prevent polluted runoff from leaving the site and supports compliance requirements. Relying only on laboratory tests misses those real-time conditions, and ignoring on-site turbidity is not acceptable because it can indicate problems before they affect receiving waters. Turbidity in surface waters matters, but monitoring on-site turbidity is essential to protect them.