NPDES Permits: What You Need To Know


Analies Dyjak  |  Hydroviv Policy Analyst

While there’s a lot of debate on what should and shouldn’t be regulated in terms of chemical discharge by companies, we thought that it would be interesting to show how regulations are used in the real-world.  In this article, we talk about the permits that allow entities to discharge chemicals into sewers and waterways.

What Is An NPDES Permit?

The National Pollutant Discharge Elimination System (NPDES)
Permits disclose which chemicals companies are allowed to discharge into waterways, and at what concentrations. The overall goal of a NPDES permit is to provide transparency between the polluter, the federal government and the public.

Who Needs To Get An NPDES Permit?

Any company, organization of private entity that has plans to discharge pollution from a point source into a United States waterway.

How Are NPDES Permits Granted & Distributed?

Technology-based and water quality based limitations are two criteria that are considered when issuing a permit. Technology-based limitations take into consideration the technology and economic ability of the polluters to control the discharge of pollutants from their facilities. Water quality-based limitations are meant to protect the body of water that the effluent is being discharged into.
Once a permitting authority or company completes a Notice of Intent (NOI) for a NPDES permit, it becomes available to the public via the Federal Register. Often local newspapers will publish a notice of the application and provide information regarding public comments.

Where Can I Find an Existing NPDES Permit?

Existing NPDES permits can be found in the General Permit Web Inventory section of the EPA’s website. Required information to search for a NPDES permit includes either the name of a state, permit number, or permitting authority.

What Should A NPDES Permit Include?

  • Information on each known contaminant must be included in a NPDES permit, whether it is regulated by the EPA or not.

  • Clear, concise, and consistent units. When a regulatory agency signs off on a NPDES permit without units, they’re essentially allowing a company to discharge a contaminant at any concentration.

  • Pertinent information that might affect concentration levels.

    • For example seasonal variance or increased turbidity.

  • A NPDES permit should also have information on monitoring such as location and frequency of sampling.

Why You Should Care About NPDES Permitting

Public participation has the ability to prolong the issuing process and can cause a company to alter their plans for dealing with chemical discharge. If you have questions regarding a NPDES permit in your area, don’t hesitate to address your concerns during the required public comment period. Be vigilant in assessing every component of the water discharge permit!

Want To Learn More About NPDES Permits And Water Policy?

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