The examination process may consist of the following: WRITTEN EXAMINATION - 100%: A job-related written examination will be administered which may test a candidates knowledge of the materials, methods, practices equipment and tools used in the installation and maintenance of valves, hydrants, water lines, meters, regulators, pumps, surface water and ground water treatment equipment, distribution and water services, basic mathematical principles, ability to communicate effectively in oral and written form, ability to establish and maintain effective working relationships with those contacted in the performance of assigned duties. Depending on assignment area: 1) may be required to obtain and maintain a valid Commercial Class "A" or "B" California Drivers License with appropriate endorsements for the entire term of employment in this classification within twelve (12) months of assignment, 2) may be required to obtain and maintain throughout the entire term of employment in this classification a valid Backflow Certificate by the California State Water Resources Control Board.