DEQ Certified Soil Profilers

Soil Tests

Before the installation of a subsurface on-site sewage treatment system, a soil test must be performed. DEQ accepts two types of soil tests to characterize soil and determine the appropriate system and sizing criteria.

Percolation tests may only be used to identify suitable areas for the installation of conventional subsurface systems, lagoons, or aerobic systems with spray irrigation. The size of the on-site sewage treatment system is  based on the percolation rate (time it takes for water to percolate through the soil).

Soil profile tests may be used to design all DEQ approved on-site sewage treatment systems.  The soil texture, presence/absence of water saturated soil, and depth to rock are used to design the most appropriate system for your property.

Other factors to consider in determining the appropriate type, size, and location of an on-site sewage treatment system includes: topography, water usage, and future land use of the property.

For additional information on soil tests, please contact your local DEQ office or call (405)702-6100.

DEQ Certified Soil Profilers

This program trains and certifies individuals to perform soil profile tests for designing on-site sewage treatment systems in Oklahoma.

Duties and Responsibilities of DEQ Certified Profilers:

  • Perform soil profile as outlined in Chapter 641.
  • Submit an accurate, completed DEQ form number 641-581 (Soil Profile) to the local DEQ office within ten (10) working days of system completion.
  • Maintain records of all soil profiles performed.

DEQ Form number 641-581 is not official unless signed by a DEQ representative.

For additional on-line information on soil, please click the following link to the OSU-DEQ Soil Book.

OSU-DEQ soil book


Call (405)702-6100 or email ECLS Onsite Licensing

DEQ Certified Soil Profiler List
DEQ Licensed Septage Pumpers and Tranpsorters List

For more information about the Oklahoma Onsite Wastewater Association (OOWA), please click on the link below.