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No Discharge Certificate FAQs

What is a No Discharge Certificate (NDC)?

The NDC was introduced in January 2020 as an optional product for facilities that do not discharge stormwater associated with industrial activities to Waters of the U.S. (WOTUS). This includes discharges directly to a WOTUS as well as discharges to a WOTUS by way of a conveyance (such as a ditch, channel, street, storm sewer, etc.). 

This means, a facility with industrial activities, equipment, products, waste products, materials, etc., that are exposed to stormwater (rain, snow, snowmelt or runoff) and could demonstrate that they do not discharge stormwater, do not need coverage under ADEQ’s Multi-Sector General Permit (MSGP) and may qualify for the optional NDC.

If stormwater associated with industrial activities will discharge from the facility, permit coverage is required by submitting a Notice of Intent (NOI) through myDEQ | Learn More >

If stormwater associated with industrial activities will discharge from the facility, however all industrial materials and activities are covered by a storm resistant shelter and not exposed to rain, snow melt or runoff,  you may qualify for a No Exposure Certificate (NEC) through myDEQ | Learn More >

How do I get an NDC?

To obtain an NDC, you must have a myDEQ account | How to Get an Account >

Once your account is set up, log in to myDEQ and select the MSGP/NEC/NDC option. This path will filter options based on a series of questions and answers. If eligible, you will be given the option to obtain a NDC. 

What information is required as part of the NDC?

The myDEQ system will ask for your place location. If you are located within a municipal separate storm sewer system (MS4), you will need to provide your sector, sub-sector, Standard Industrial Classification (SIC) Code and the reason(s) why stormwater associated with industrial activities will not discharge to a WOTUS.  Some of the reasons may include: retention basins, drywells, berming, curbing, reuse of stormwater, off-site disposal, etc. Currently, engineering calculations or site maps are not required.

Note: It is important to maintain documentation at the site that demonstrates the conditions of no discharge. If at any time, site conditions change or control measures are removed or modified, the site should be re-evaluated for the requirements of no discharge.

Do I have to get an NDC?

No, you are not required to obtain an NDC. It is an optional certification. The NDC is not a permit condition or a requirement in federal or Arizona rules. If you acquire an NDC, you may cancel it at any time.

What is the benefit of getting an NDC?

Obtaining a NDC provides documentation for the facility owner/operator that they pursued permit coverage and determined there was no potential for stormwater from the facility to discharge to a WOTUS.

How much does an NDC cost?

There is no initial fee or annual fee associated with an NDC.

How long is the NDC good for?

The NDC is issued for a five-year term, meaning the certificate expires five years from the date it was certified and submitted through myDEQ. Prior to the five-year expiration date, you will receive notification through myDEQ that the NDC expiration is near, and that you may resubmit, if you like. The NDC may also be cancelled by the facility at any time. The resubmission and cancellation paths are available online through myDEQ.

I don’t know if my site discharges industrial stormwater off-site. Should I get the NDC or get an NOI?

If you are unsure if industrial stormwater will discharge from your site, you may want to seek an engineering analysis to verify and ensure NDC eligibility. If you are unable to certify that industrial stormwater will not discharge, ADEQ recommends that you obtain permit coverage and comply with state and federal rules. If, at later date, you determine that stormwater will not discharge, you can terminate your permit coverage and obtain an NDC.

Part of my industrial site does not discharge stormwater, but other industrial areas of the site discharge stormwater to an ephemeral wash. Can I get the NDC for a portion of the site?

No, similar to obtaining permit coverage (obtaining an NOI) or a No Exposure Certification (NEC), an NDC is comprehensive and must apply to the entire site.

Stormwater used to discharge from my site, but control measures have been designed and implemented so that stormwater no longer discharges, can I still get an NDC? 

Yes, you can terminate your NOI and get an NDC.

Can I get an NDC if stormwater discharges to an ephemeral wash within my own property boundary?

No. A stormwater discharge to an ephemeral wash within your property is still considered a discharge to a WOTUS that requires an MSGP, unless a determination has been made that the wash is not jurisdictional or conveys the stormwater to a WOTUS.

How does ADEQ know I do not discharge? Will they come out to verify this?

ADEQ is not approving or concurring that your site does not discharge stormwater. When obtaining an NDC, you are certifying that the information you provided is true and accurate and, you are ultimately responsible for ensuring that your facility does not discharge stormwater.

ADEQ does retain the authority to inspect the facility in order to verify that there is no discharge to a WOTUS, either directly or by way of a conveyance.

Do I need to prepare a Stormwater Pollution Prevention Plan (SWPPP) if I get an NDC?

No, you do not need to prepare a SWPPP if you are eligible for the NDC. However, ADEQ recommends that you develop and implement a plan to periodically inspect site conditions to ensure NDC eligibility requirements are still being met. 

How is an NDC different than a No Exposure Certificate (NEC)?

The NEC is for facilities that would otherwise be regulated by the MSGP but are exempt from the requirement to obtain a permit because there is no exposure of industrial materials or activities to precipitation or runoff.  Under the NEC, stormwater may be discharged to a WOTUS, but the industrial materials and activities at the site must be covered by a storm resistant shelter and not exposed to rain. For an NDC, industrial material and activities can be exposed to precipitation, however, none of the industrial stormwater goes to a WOTUS.

What happens if I have an NDC and there is a storm event that results in a discharge?

The federal Clean Water Act (CWA) and Arizona rules specify that it is a violation to discharge without a permit. ADEQ encourages customers to assess their site and maintain control measures to ensure an unpermitted discharge will not occur. ADEQ retains its enforcement authority for violations, including unpermitted discharges.1