This unit describes the skills required to identify microorganisms and assess the appropriate drinking water or water re-use treatment processes for inactivation or removal.

This unit applies to those working as water treatment operators responsible for water quality in a range of technical and process applications in water and wastewater treatment.

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.

Those undertaking this unit would work autonomously performing sophisticated tasks in 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. Candidate must be assessed operating at least one of the processes, treating at least one of the problems, listed in Range of Conditions. If not otherwise specified the candidate must demonstrate evidence of performance of the following on at least one occasion.

identifying a range of waterborne microorganisms

analysing general characteristics caused by waterborne microorganisms, including at least one of:

pathogenicity

virulence

resistance to disinfectants

opportunistic infection capability

analysing types of problems caused by waterborne microorganisms, including at least one of:

nuisance problems

taste and odour

filter clogging

colour

corrosion

toxicity problems

pathogenic problems

identifying pathogenic microorganisms and the diseases they cause, including at least one of:

viruses

bacteria

protozoa

algae

cyanobacteria

helminths

assessing and selecting water or re-use treatment processes for physically removing or deactivating pathogenic microorganisms, including at least one of:

filtration

slow sand filter

granular media filters

membrane filters

disinfection:

chlorination

chloramination

UV

chlorine dioxide

ozone

assessing causes of nuisance and toxicity problems, including at least one of:

micro types:

diatoms

sulphur bacteria

cyanobacteria:

Microcystis aeruginosa

Anabaena circinalis

pathogenic microorganisms:

viruses

enterovirus

hepatitis A

hepatitis E

rotavirus

bacteria:

Campylobacter

Salmonella

Escherichia coli

protozoa species:

Giardia

cryptosporidium

Nagleria

helminths, including Ascaris lumbricoides

selecting pre- or post-treatment processes for removing the causes of nuisance and toxicity problems, including at least one of:

micro-straining

algicides

activated carbon

ozone-biologically activated carbon (BAC)

preparing reports on the optimum treatment for a range of microorganisms, including measures to ensure validity

preparing and applying chemical dosing as required

assessing process performance

reviewing existing process barrier performance with reference to historical data, differences in raw water quality and plant configuration

identifying data deficiencies and additional data collection through sampling and testing

assessing fault reports and investigating current operational status of processes for microorganism removal

investigating current and potential chemical addition practices

planning trials to test the performance of the treatment optimisation options for microorganism removal

preparing recommendation reports

applying calculations to determine log removal values for physical barriers and contact time for disinfection

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.

types, lifecycle, characteristics of waterborne microorganisms, including:

evolutionary development

source

structure

life cycle

growth rates and requirements

nuisance problems caused by waterborne microorganisms

toxicity and pathogenic problems caused by waterborne microorganisms, including:

typhoid

cholera

ascariasis

hepatitis

giardiasis

cryptosporidiosis

gastroenteritis

tuberculosis

relevant legislation, standards and workplace policies and procedures relating directly to the control and treatment of waterborne microorganisms

principles of water or re-use treatment processes

log removal value concept for physical barriers

Ct concept for disinfection

properties and modes of action of disinfectants

properties and modes of action for physical barriers

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.

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

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