This unit describes the skills required to review, coordinate and optimise chemical addition processes and to evaluate and report on system performance and process quality control.

This unit applies to those working as technical staff with a responsibility for optimising chemical addition processes in water, wastewater and stormwater treatment plants and processes.

The skills and knowledge described in this unit must be applied within the legislative, regulatory and policy environment in which they are carried out. Organisational policies and procedures must be consulted and adhered to, particularly those relating to manufacturer and plant designer specifications, dosing pump capacity and calibration chart.

Those undertaking this unit would work as single operator or as part of a team with some responsibility for team coordination and supervision, depending on the size of the treatment plant. They would perform complex tasks within a familiar context.

No licensing, legislative or certification requirements apply to unit at the time of publication.

Evidence required to demonstrate competence must satisfy all of the requirements of the elements and performance criteria. If not otherwise specified the candidate must demonstrate evidence of performance of the following on at least one occasion.

conducting investigations and reporting on operational and control system problems

coordinating sampling and testing including at least one of:

jar testing

flocculation growth

mixing energy

UV absorbance

pH

colour

turbidity

residual inorganic compounds

alkalinity

conductivity

assessing quality of treatment chemicals by conducting a full range of jar tests

performing mathematical calculations to provide data for the analysis and development of options and solutions

investigating chemical dosing

interpreting a range of complex and technical documents, including at least one of:

regulatory, legislative, licensing and organisational requirements

codes and standards

specifications

organisational policies

articulating complex ideas

analysing and evaluating reports and reference materials

analysing problems and recommending appropriate remedial solutions

identifying and responding to risks and hazards

identifying opportunities for improved water treatment

reviewing existing process performance with reference to historical data, differences in raw water quality and plant configuration including at least one of:

pH

turbidity

colour

presence of algae

temperature

identifying data deficiencies and plan additional data collection through appropriate sampling and testing

assessing fault reports and investigating the current operational status of plant components

investigating current and potential chemical addition practices

planning trials to test the performance of the determined optimisation options and compiling recommendation reports

Evidence required to demonstrate competence must satisfy all of the requirements of the elements and performance criteria. If not otherwise specified the depth of knowledge demonstrated must be appropriate to the job context of the candidate.

the role of chemical addition in water treatment

the principles of chemical addition, including enhanced coagulation

chemical addition plant and equipment and system layout including:

mixing equipment

streaming current detector

dosing pumps

chemical injection equipment

turbidity meter

particle counter

flow meters

chemical concepts and reactions relevant to chemical addition processes, including pH and alkalinity

range and characteristics of chemicals used in chemical addition processes including:

polyaluminium chloride (PACL)

aluminium sulphate

aluminium chlorohydrate (ACH)

ferric chloride

ferric sulphate

polyDADMAC

polyacrylamide

sulphuric acid

hydrated lime

caustic soda

functions of various chemicals in chemical addition processes

factors influencing the effectiveness of chemicals in chemical addition processes

factors affecting the selection of chemicals in chemical addition processes

range of appropriate measuring and testing procedures

investigation procedures

risk management principles

locating chemical dosing points including at least one of:

mixing or reaction detention times

type of mixer or impeller

customer expectations and requirements

dosing pump capacity and calibration chart including:

detention times

mixing intensity for flash or rapid mixing and flocculation

Consideration must be given to holistic assessment for this unit. Refer to advice in the companion volumes.

Competency should be assessed in an actual workplace or in a simulated environment, with access to equipment and infrastructure appropriate to the outcome. Competency should be demonstrated over time to ensure the candidate is assessed across a variety of situations.

Some components of this unit require assessment in a workplace environment therefore the unit is not suitable for fully external or electronic based assessment.

Assessors must satisfy the NVR/AQTF mandatory competency requirements for assessors.

The foundation skills demands of this unit have been mapped for alignment with the Australian Core Skills Framework (ACSF). The following tables outline the performance levels indicated for successful attainment of the unit.

Further information on ACSF and the foundation skills underpinning this unit can be found in the Foundation Skills Guide on the GSA website.

Treatment