Application
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.
Elements and Performance Criteria
ELEMENTS | PERFORMANCE CRITERIA |
Elements describe the essential outcomes | Performance criteria describe the performance needed to demonstrate achievement of the element. Where bold italicised text is used, further information is detailed in the range of conditions section. |
1. Assess performance of processes to remove microorganisms | 1.1 Review existing process performance data. 1.2 Review existing operational processes with reference to manufacturer and plant designer specifications. 1.3 Identify the impact of raw water quality on water treatment effectiveness for microorganism removal. 1.4 Review existing fault reports and other relevant plant asset information. 1.5 Investigate the operational status of plant components. 1.6 Investigate the cause of treated water quality issues relating to microorganisms. 1.7 Assess the effectiveness of process control strategies for microorganism removal. |
2. Improve process performance for removal of microorganisms | 2.1 Identify treatment process conditions for optimising microorganism removal. 2.2 Determine plant configuration and revised operational processes for process optimisation. 2.3 Plan a trial to test the performance of the determined optimisation options. |
3. Report on system performance and improvement | 3.1 Report on the current operational status of the water treatment process. 3.2 Report on effective treatment processes and associated sampling and testing procedures to maintain water quality. 3.3 Compile a report making recommendations on optimisation options. |
Evidence of Performance
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 of Knowledge
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
Assessment Conditions
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.
Foundation Skills
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.
Range Statement
Treatment processes include: | source water management pre-treatment processes to address problems associated with waterborne microorganisms physical treatment processes to remove waterborne microorganisms disinfection processes to kill or deactivate waterborne microorganisms |
Associated problems with microorganisms include: | algal toxins taste and odour compounds disinfection by-products regrowth, nitrification & disinfection failure |
Competency Field
Treatment