WFWX 0003 - Water Treatment Plant Operation Levels B & C, Module 1 Add to Personal Catalog WFWX 0003 - Water Treatment Plant Operation Levels B & C, Module 1 This module covers such topics as defining the characteristics of raw water, pretreatment of raw water, primary treatment of water for drinking water, and chemical disinfection of water. Successful completion of WFWX 0003, WFWX 0004 , and WFWX 0005 fulfills course requirements to sit for the operator certification exam for Water Treatment Level B or Level C. Click here for the Summer 2026 Class Schedule Click here for the Fall 2026 Class Schedule