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On-site sewage system designers

These licenses are provided through the Washington State Department of Licensing. For more information,

Visit the Board of Registration for Professional Engineers & Land Surveyors

Certifications offered by King County

Associate/master installer

Learn about the on-site sewage associate and master installer certifications.

On-site system maintainer

Find information about the on-site sewage system maintainer certification.

Liquid waste pumper/hauler

Learn about the liquid waste pumper/hauler certification.