Environmental Health maintains a current list of septic system professionals that are certified to perform services
in Thurston County. Although we strive to keep these lists current, we recommend you check with your contractor to make sure they are still certified.
To be certified, contractors must pass a test and have their equipment (i.e. pump trucks) inspected every three years
(for specific requirements, see
Article IV [PDF], Section 23).
Thurston County does not regulate the business practices of certified contractors.
Get several estimates, check references, and be clear what services are requested
before hiring a contractor.
The following contractors are certified to perform services in Thurston County.
Designers / Professional Engineers
Can evaluate soil suitability and subsequently design an appropriate septic system. For a list of designers, see
WA State Licensed Sewage System Designers [PDF].
NOTE: Designers are licensed by
Washington State Department of Licensing, not by Thurston County.
Can install new systems, make repairs, and modifications; also can replace pumps, septic tanks, pump chambers, and
holding tanks. For a list of installers, see Certified Sewage System Installers [PDF].
Can inspect and pump septic tanks, make minor repairs (such are sealing cracks and replacing baffles), pump and
dispose of septage. For a list of pumpers, see Certified Sewage System Pumpers [PDF].
Can monitor Aerobic Treatment Units (ATUs) and other septic systems. For a list of monitoring specialists, see
Certified Monitoring Specialists [PDF].
Forms, manuals, and other information for septic
system professionals doing business in Thurston County.