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Groundwater Discharge Licenses



The DNREC Division of Water issues licenses for the various professions involved in designing, installing and maintaining on-site wastewater treatment and disposal systems. Licenses are granted under the state’s on-site systems regulations and with input from the On-Site Systems Advisory Board.

Any work performed on an on-site system treatment system in Delaware should be performed by a licensed contractor approved by the Board.

Groundwater discharge licenses are issued under the state’s Regulations Governing the Design, Installation and Operation of On-Site Wastewater Treatment and Disposal Systems (7 DE Admin. Code 7101) available as a PDF version with exhibits and attachments.

Licenses are applied for online, using the Digital DNREC ePermitting system.

The ePermitting system offers online applications for licenses and permits throughout the department. It allows users to manage their own portfolio of licenses and permits.

Those unable to take advantage of the Digital DNREC ePermitting system can contact the Division of Water at 302-739-9116.

License Types and Licensee Lists

Groundwater discharge licenses are issued in eight different classes, focused on different aspects of systems design, installation and maintenance. All licenses require submission of a completed application and review by the On-Site Systems Advisory Board. They must be renewed annually.

Property owners who wish to conduct their own percolation testing, system design or system installation on their own property and for their own use my apply for a temporary Class A, B, or E license.

All on-site wastewater treatment and disposal system licensees are listed on the Delaware Open Data Portal in a data-set that is updated weekly.

Class A – Percolation Tester

Class A Licenses authorize the performance of percolation tests. (Licensee List)

Class B – Designer

Class B licenses authorize the design of conventional on-site wastewater treatment and disposal systems which utilize gravity distribution systems for seepage beds and seepage trenches and certain standardized pressure distribution and disposal systems. (Licensee List)

Class C – Designer

Class C licenses authorize the design of conventional, alternative and experimental on-site wastewater treatment and disposal systems and all pressure distribution systems. (Licensee List)

Class D – Site Evaluator

Class D licenses authorize the performance of site evaluations. (Licensee List)

Class E – System Contractor/Installer

Class E licenses authorize the construction and installation of wastewater treatment and disposal systems. (Licensee List)

Class F – Liquid Waste Hauler

Class F licenses authorize the removal, transportation or disposal of the solid and liquid contents of septic tanks, cesspools, grease traps, seepage pits, holding tanks, portable toilets or other wastewater treatment or disposal facilities as specified and required under the Regulations. (Licensee List)

Class H – System Inspector

Class H licenses authorize the inspection, investigation and data collection to make determinations regarding the operational condition of on-site wastewater treatment and disposal systems. (Licensee List)

Class I – Construction Inspector

Class I licenses authorize the inspection of all new, replacement and repairs of small gravity on-site wastewater treatment and disposal systems, gravity on-site system component replacements and cover inspections for above grade gravity on-site wastewater treatment and disposal system. (Licensee List)

Delaware Technical & Community College Environmental Training Center

Delaware On-Site Wastewater Recycling Association




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