Introduction

The National Pollutant Discharge Elimination System (NPDES) stormwater program regulates stormwater discharges from three possible sources: municipal separate storm sewer systems (MS4s), construction activities, and industrial activities. This Fact File will focus on stormwater discharges from construction activities. It explains frequently associated construction pollutants, the harm they can do, and construction stormwater permit descriptions and requirements. With proper permit knowledge related to stormwater discharges from construction activities, you can better help the environment and stay in compliance to avoid hefty fines.

Background

There are certain federal acts to be aware of in connection to stormwater discharges from construction. One of which is the national Water Pollution Control Act, which is also called the Clean Water Act (CWA). It was enacted in 1972. It says that the discharge of pollutants to U.S. waters from any point source is illegal unless the discharge complies with an NPDES permit. The Clean Water Act amendments of 1987 required the U.S. Environmental Protection Agency (EPA) to adopt regulations to require NPDES permits of storm water discharges related to construction actions. On November 16, 1990, the EPA published final regulations that set the requirements for stormwater permit applications for certain categories of industries.

Construction pollutants

When it rains, stormwater washes over the loose soil on a construction site, along with materials and products that may be stored outdoors. As stormwater flows over the site, it can gather pollutants such as sediment, debris, and chemicals, and transport them to nearby storm sewer systems or directly into rivers, lakes, or coastal waters.

Working together with construction site operators, the EPA ensures that appropriate stormwater controls are implemented so that construction activities can proceed in a manner that protects water quality and the surrounding environment.

There are some pollutants that are frequently associated with construction sites. These include:

• Sediment
• Solid and sanitary wastes
• Phosphorus
• Nitrogen
• Pesticides
• Oil and grease
• Concrete truck washout

Sediment is widely recognized as the primary pollutant of concern associated with construction stormwater runoff due to the large volumes generated from disturbed soil.

In a short period of time, construction activities can contribute significant amounts of sediment to nearby waterbodies, particularly when soil is exposed and not properly controlled. This, along with other pollutants, can result in physical, chemical, and biological impacts to surface waters.

Excess sediment can:

• Fill rivers, lakes, and reservoirs, increasing the need for dredging and reducing storage capacity;
• Reduce sunlight penetration, affecting aquatic plant growth;
• Smother aquatic habitats and spawning areas; and
• Clog fish gills and impair aquatic life.

NPDES permit description

A Clean Water Act permit is necessary for stormwater discharges from any construction activity disturbing:

• One acre or more of land, or
• Less than one acre of land, but that is part of a common plan of development or sale that will eventually disturb one or more acres of land.

Construction activity includes earth-disturbing actions like clearing, grading, and excavating land and other activities that could produce pollutants.

All National Pollutant Discharge Elimination System (NPDES) permits for construction stormwater must address the minimum federal effluent limitation guidelines for the construction and development point source category. This is commonly called “the C&D rule.” The C&D rule sets minimum NPDES effluent limitations, like:

1. Design, install, and preserve effective erosion and sediment controls, and pollution prevention measures, to diminish pollutant discharge;
2. Stabilize disturbed areas right away when construction has stopped and will not continue for over 14 days;
3. Forbid the dewatering discharges unless managed by suitable controls;
4. Forbid the discharge of:
   • Wastewater from concrete washout (unless managed by suitable control), or washout/cleanout of stucco, paint, form release oils, other wastewater materials;
   • Fuels, oils, or other pollutants used for vehicles; and
   • Soaps of solvents to wash vehicles and equipment

Construction general permit requirements

The Construction General Permit (CGP) covers stormwater discharges from construction activities in areas where EPA is the NPDES permitting authority. The main requirements under this permit are to:

• Develop a Stormwater Pollution Prevention Plan (SWPPP) and keep it up to date.
• Complete and submit a Notice of Intent (NOI) to EPA via the NPDES eReporting Tool (NeT).
• Implement erosion and sediment controls and pollution prevention practices throughout construction.
• Conduct mandatory inspections to confirm compliance with permit. Inspections may only be conducted by a qualified person who has either: (1) completed the EPA construction inspection course and passed the exam, or (2) holds an up-to-date construction inspection certification or license from a program that covers the same core material as EPA’s inspection course.
• Conduct routine maintenance and take remedial action to correct issues with controls or discharges.
• Complete documentation of all site inspections, dewatering inspections, and corrective actions.
• Comply with turbidity monitoring requirements for dewatering discharges to sensitive waters (if appropriate).
• Comply with any state, tribal, or territory-specific requirements of the permit.

Applicable laws & regulations

40 CFR 450 — Construction and Development Point Source Category

Related definitions

Dewatering discharges: Construction-related discharges, including drainage water (surface rainwater and groundwater) and process water.

Point source: Any one identifiable source of pollution from which pollutants are discharged, like a pipe, ditch, ship, or factory smokestack.

Solvent: A liquid that is a single chemical or a mixture of chemicals used to dissolve a substance or material.

Key to remember

Overall, you need to obtain coverage under an NPDES permit if you are considered an operator of the construction site because you have operational control over:

• Construction plans and specifications, including the capability to make changes to them; or
• Day-to-day control of site activities at a project that are essential to ensure compliance with permit conditions (e.g., authorized to direct workers at a site to carry out activities mandated by the permit).

If this role description does not sound like you, then you are not the person to obtain coverage under an NPDES permit.

Real world example

Because stormwater discharges have the potential to significantly impact the environment, the EPA and authorized states take NPDES permit compliance very seriously under the Clean Water Act.

Failure to comply with permit requirements can result in enforcement actions, including civil penalties and required corrective measures.

For example, a lumber company in Springfield, Oregon allegedly violated the Clean Water Act by failing to comply with conditions of its NPDES permit, which authorized discharges to the Willamette River. Reported alleged violations included failure to:

• Properly document best management practices in the facility’s Stormwater Pollution Control Plan (SWPCP)
• Develop corrective action reports for benchmark exceedances
• Minimize exposure of a fixed fueling area to precipitation and runoff
• Minimize exposure of leak-prone equipment to precipitation and runoff
• Properly cover waste materials
• Conduct required annual employee training
• Update the facility’s SWPCP

Under a proposed agreement with EPA, the company agreed to pay a civil penalty of $64,500.

To avoid similar enforcement actions, facilities should ensure they fully comply with all applicable conditions of their NPDES permit, including implementing BMPs, maintaining accurate documentation, conducting required inspections and training, and promptly addressing corrective actions.