• Department of Environmental Protection (DEP) strives to grant all interested operators the opportunity to register for an exam and to obtain certification. • The exams you take will vary depending on your classification and the treatment technology at your system. • Operators need to know the treatment technologies their plant uses so they can take the proper exams to be in compliance. • To take the Proper exam(s) and receive the appropriate certificate, operators should check with their plant supervisor, NPDES or PWS Permit.