Healthy Homes, Part 10: On-site Wastewater Treatment Course

Welcome to InterNACHI's free, online Healthy Homes, Part 10: On-site Wastewater Treatment Course.  This is part 10 of a 14-part Certified Healthy Homes Inspector certification program provided by InterNACHI to members for free. 
The goal of this course is to teach students about the treatment of human waste, including on-site wastewater treatment systems. 
Upon successful completion of this course, students will be able to:
  • discuss the importance of septic tanks;
  • describe the public health and sanitation issues regarding septic tanks;
  • explain the methods used in evaluating septic tanks;
  • distinguish between various forms of septic tank systems;
  • describe alternative forms of septic tank systems; and
  • explain general maintenance and care for septic systems; 
  • perform an inspection related to treating human waste; 
  • generate observations related to inspecting wastewater treatment; and 
  • produce written reports related to observations conducted at a house.

Course Includes:
  • 20 InterNACHI CE credits
  • 2.0 CEU
  • 7,686 words
  • 20 quiz questions in four quizzes
  • Inspection and writing assignment
  • Research and writing assignment
  • 20-question final exam
  • Certificate of Completion 
You will learn the following topics:
  • Short history
  • On-site systems
  • Treatment of human waste
  • On-site wastewater treatment systems
  • Septic tank systems
  • Absorption field site evaluation
  • Absorption field trench
  • Alternative septic tank systems
  • Mound systems
  • Low-pressure pipe systems
  • Plant-rock filter systems
  • Maintaining on-site wastewater treatment systems
  • Do's and dont's 
  • Symptoms of septic system problems
  • Septic tank inspection
  • Inspection process
  • Scum measurement
  • Sludge measurement 
 This course has been approved by:
Healthy Homes, Part 10: On-site Wastewater Treatment Course. 

Course # 4820



Estimated hours for the average student

Academic Engagement

Reading online course instructional material at 140 words per minute


Taking quizzes 


Taking the exam


Conducting a directed and independent inspection study performed according to the Standards of Practice, including the development of an inspection report 


Submitting an inspection and writing assignment

Submitting a research and writing assignment 0.5




Studying and reviewing instructional material in preparation for taking quizzes and exam 


Reading the downloaded student course book including taking the quizzes with the book 0.6
Reading, research, and studying related to completing the research and writing assignment 1.0
Studying and preparing for inspection processes according to a Standards of Practice, including capturing and storing digital images with a camera or device, making observations, evaluating conditions, deducing, formulating opinions, communicating observations in written form, attaining competency in performing inspections and using an inspection checklist or software and other inspection tools in producing a report. 10.0



Sub Total


Overall Total

20 hours

2.0 CEU

And, in keeping with InterNACHI's commitment to Continuing Education, this online course is open and free to all members, and can be taken again and again, without limit.
Reminder to members:  InterNACHI's Code of Ethics 1.10 requires that you comply with all government rules and licensing requirements of the jurisdiction where you conduct business.  InterNACHI's courses and Standards generally exceed the Standards of Practice that you are required to abide by locally.