Roles and responsibilities: On-site wastewater design professionals

Due to facility issues, this licensing program has limited operations. There may be delays in responding to requests. We apologize for the inconvenience. We’re working toward resuming all business operations as soon as possible.

General areas of responsibility

A practicing on-site wastewater design professional:

  • Performs services for new construction of a system.
  • Evaluates existing on-site disposal systems.

Subjects typically addressed by on-site wastewater design professionals

The following examples are general guidelines, and shouldn’t be considered all inclusive.

Design area Subjects addressed by on-site wastewater design professionals
Site evaluation
  • Existing site and system conditions
  • Potable water source and utilities
  • Topography and property information
  • Surface water, ground water, and drainage
Evaluation of soil
  • Soil logs, sampling, and classifications
  • Impervious layers and seasonal water table
  • Fill areas and other adverse soil conditions
  • Type of disposal system
  • System components and operational parameters
Construction management
  • Disposal site preparation
  • Construction conformance with design
  • Report construction and site variances
  • Operational testing and owner use



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