SAQA All qualifications and part qualifications registered on the National Qualifications Framework are public property. Thus the only payment that can be made for them is for service and reproduction. It is illegal to sell this material for profit. If the material is reproduced or quoted, the South African Qualifications Authority (SAQA) should be acknowledged as the source.
SOUTH AFRICAN QUALIFICATIONS AUTHORITY 
REGISTERED UNIT STANDARD: 

Operate and control activated sludge process 
SAQA US ID UNIT STANDARD TITLE
255984  Operate and control activated sludge process 
ORIGINATOR
SGB Water Sector 
PRIMARY OR DELEGATED QUALITY ASSURANCE FUNCTIONARY
-  
FIELD SUBFIELD
Field 12 - Physical Planning and Construction Civil Engineering Construction 
ABET BAND UNIT STANDARD TYPE PRE-2009 NQF LEVEL NQF LEVEL CREDITS
Undefined  Regular  Level 4  NQF Level 04  12 
REGISTRATION STATUS REGISTRATION START DATE REGISTRATION END DATE SAQA DECISION NUMBER
Reregistered  2018-07-01  2023-06-30  SAQA 06120/18 
LAST DATE FOR ENROLMENT LAST DATE FOR ACHIEVEMENT
2024-06-30   2027-06-30  

In all of the tables in this document, both the pre-2009 NQF Level and the NQF Level is shown. In the text (purpose statements, qualification rules, etc), any references to NQF Levels are to the pre-2009 levels unless specifically stated otherwise.  

This unit standard replaces: 
US ID Unit Standard Title Pre-2009 NQF Level NQF Level Credits Replacement Status
12056  Operate activated sludge process  Level 4  NQF Level 04  18  Complete 

PURPOSE OF THE UNIT STANDARD 
This unit standard is intended for persons operating and controlling an activated sludge process. Learners will be able to treat wastewater by removing dissolved and suspended organic material to ensure a good quality effluent. This competence will enable the learner to operate the activated sludge process at various wastewater works. This knowledge will contribute towards the protection of the water environment in accordance with legislation and regulations.

Learners credited with this unit standard will be able to:
  • Identify and explain the different types of activated sludge systems.
  • Control activated sludge systems.
  • Assess activated sludge plant performance.
  • Operate nitrogen removal activated sludge plant.
  • Operate biological phosphate removal activated sludge plant.
  • Operate chemical phosphate removal activated sludge plant.
  • Control sludge carry-over.
  • Identify and discuss health risks and dangers associated with activated sludge process. 

  • LEARNING ASSUMED TO BE IN PLACE AND RECOGNITION OF PRIOR LEARNING 
    It is assumed that learners are competent in:
  • Mathematical literacy at NQF Level 3.
  • Communication skills at NQF Level 3.

    It is assumed that learners are competent in the following unit standards:
  • ID 254116 Demonstrate knowledge of activated sludge processes at NQF Level 3.
  • ID 7812 Perform calculations at NQF Level 3. 

  • UNIT STANDARD RANGE 
    Work policies and procedures:
  • Best operating procedures.

    Aerators:
  • Surface, diffused air.

    Sludge:
  • Return, waste, mixed liquor activated sludge, conventional, extended aerator, sequential batch reactor.

    General maintenance:
  • Check nuts and bolts and gear wheels, maintain cleanliness of equipment, check for water in oil, grease bearings, replenish oil, machine guards, gland packing.

    Ad hoc sample:
  • Emergency, special request.

    Reports:
  • Maintenance, faults, irregularities in influent, power failures, mechanical breakdowns, dissolved oxygen measurements. 

  • Specific Outcomes and Assessment Criteria: 

    SPECIFIC OUTCOME 1 
    Identify and explain the different types of activated sludge systems. 
    OUTCOME RANGE 
    Different types of systems include but is not limited to conventional, extended aeration, Sequencing Batch Reactor (SBR), package plants and biological nutrient removal (BNR). 

    ASSESSMENT CRITERIA
     

    ASSESSMENT CRITERION 1 
    Each type of activated sludge system is drawn and explained using a schematic diagram. 

    ASSESSMENT CRITERION 2 
    The different methods of operation are explained in terms of a diagram. 

    ASSESSMENT CRITERION 3 
    The advantages and disadvantages of each system are discussed in relation to local requirements. 

    SPECIFIC OUTCOME 2 
    Control activated sludge systems. 
    OUTCOME RANGE 
    Systems includes but is not limited to sludge age and mixed liquor suspended solids, Dissolved Oxygen concentration and recycle rate. 

    ASSESSMENT CRITERIA
     

    ASSESSMENT CRITERION 1 
    Volumes of sludge to be wasted is calculated in order to specify the sludge age. 

    ASSESSMENT CRITERION 2 
    Dissolved Oxygen test is performed in order to control the nitrification. 

    ASSESSMENT CRITERION 3 
    An ability to alter the Dissolved Oxygen is demonstrated in order to control nitrification. 

    ASSESSMENT CRITERION 4 
    An ability to perform the half-hour settling is demonstrated in order to control solids volumes in the clarifier. 

    SPECIFIC OUTCOME 3 
    Assess activated sludge plant performance. 

    ASSESSMENT CRITERIA
     

    ASSESSMENT CRITERION 1 
    Substances that must be removed or reduced by the activated sludge process are explained in terms of carbonaceous removal, ammonia removal, de-nitrification and phosphate removal. 

    ASSESSMENT CRITERION 2 
    Factors that can be used to remove or reduce the required substances to the level specified are identified and described in terms of the effectiveness of the process. 
    ASSESSMENT CRITERION RANGE 
    Factors include but is not limited to Dissolved Oxygen, recycling rate and wasting rate.
     

    SPECIFIC OUTCOME 4 
    Operate nitrogen removal activated sludge plant. 

    ASSESSMENT CRITERIA
     

    ASSESSMENT CRITERION 1 
    The requirements for nitrification are explained in order to achieve adequate ammonia removal. 
    ASSESSMENT CRITERION RANGE 
    Requirements include but is not limited to adequate sludge age and aerobic conditions.
     

    ASSESSMENT CRITERION 2 
    The requirements for de-nitrification are explained in order to meet the nitrate license requirements. 
    ASSESSMENT CRITERION RANGE 
    Requirements of de-nitrification refer to but is not limited to anoxic zones and adequate carbonaceous content.
     

    SPECIFIC OUTCOME 5 
    Operate biological phosphate removal activated sludge plant. 

    ASSESSMENT CRITERIA
     

    ASSESSMENT CRITERION 1 
    The three zones necessary for biological phosphate removal are identified and described in order meet the specified phosphate concentration. 
    ASSESSMENT CRITERION RANGE 
    Zones include but is not limited to anaerobic, anoxic and aerobic.
     

    ASSESSMENT CRITERION 2 
    The requirements for phosphate removal are explained in order to meet the phosphate license requirements. 
    ASSESSMENT CRITERION RANGE 
    Requirements of phosphate removal refer to but is not limited to anaerobic, anoxic and aerobic zones, adequate carbonaceous content, the presence of acinetobacter bacteria and the achievement of complete de-nitrification.
     

    ASSESSMENT CRITERION 3 
    The processes taking place in each of the three zones are explained in terms of the presence of bacteria and oxygen preference. 

    SPECIFIC OUTCOME 6 
    Operate chemical phosphate removal activated sludge plant. 

    ASSESSMENT CRITERIA
     

    ASSESSMENT CRITERION 1 
    Chemicals used for the stabilization of wastes activated sludge are identified and described in terms of their uses in order to prevent release of phosphate into the environment. 

    ASSESSMENT CRITERION 2 
    The phosphate that is trapped in the waste sludge is stabilized by means of chemicals. 

    ASSESSMENT CRITERION 3 
    The desired output of the results is compared with actual results obtained in order to make recommendations for the adjustment of the process, if necessary. 

    SPECIFIC OUTCOME 7 
    Control sludge carry-over. 

    ASSESSMENT CRITERIA
     

    ASSESSMENT CRITERION 1 
    Possible causes of solids carryover are identified and explained in order to take corrective action. 
    ASSESSMENT CRITERION RANGE 
    Possible causes include but is not limited to de-nitrification, norcardia infestation and excessive filamentous growth.
     

    ASSESSMENT CRITERION 2 
    The Dissolved Oxygen concentration and the mixed liquor leaving the aeration tank is adequate to prevent de-nitrification. 

    ASSESSMENT CRITERION 3 
    Methods to reduce narcodia growth are identified and explained in terms of effectiveness. 
    ASSESSMENT CRITERION RANGE 
    Methods include but is not limited to reducing Dissolved Oxygen , application of chlorine, physical removal and wetting the scum to break it up.
     

    ASSESSMENT CRITERION 4 
    Methods to reduce filamentous growth are identified and explained in terms of effectiveness. 
    ASSESSMENT CRITERION RANGE 
    Methods include but is not limited to reducing Dissolved Oxygen and application of chlorine.
     

    SPECIFIC OUTCOME 8 
    Identify and discuss health risks and dangers associated with activated sludge process. 
    OUTCOME RANGE 
    Health risks refers to but is not limited to pathogenic organisms carried in aerosols and dangers refers to but is not limited to drowning, lack of illumination and other unsafe conditions. 

    ASSESSMENT CRITERIA
     

    ASSESSMENT CRITERION 1 
    Work policies and procedures relating to activated sludge process are described in terms of occupational Health and Safety Act. 

    ASSESSMENT CRITERION 2 
    Access points of the activated sludge plant are described. 

    ASSESSMENT CRITERION 3 
    Safety precautions are identified and applied in order to prevent injury and/or loss of life in an activated sludge plant. 
    ASSESSMENT CRITERION RANGE 
    Safety precautions include but is not limited to hand railing, use of safety belts and an attendant.
     


    UNIT STANDARD ACCREDITATION AND MODERATION OPTIONS 
  • Anyone assessing a learner or moderating the assessment of a learner against this unit standard must be registered as an assessor with the relevant ETQA.
  • Any institution offering learning that will enable the achievement of this unit standard must be accredited as a provider with the relevant ETQA.
  • Assessment and moderation of assessment will be overseen by the relevant ETQA according to the ETQA`s policies and guidelines for assessment and moderation.
  • Moderation must include both internal and external moderation of assessments at exit points of the qualification, unless ETQA policies specify otherwise. Moderation should also encompass achievement of the competence described both in individual unit standards as well as the integrated competence described in the qualification. 

  • UNIT STANDARD ESSENTIAL EMBEDDED KNOWLEDGE 
    Learners should have a knowledge and understanding of:
  • Relevant sections of Legislation: OHS Act, National Water Act, local by-laws.
  • The importance of following relevant work policies and procedures.
  • The tests done on process samples, interpretation of results and corrective action.
  • The principles of the activated sludge process.
  • The causes of unit process malfunctions.
  • Alternative ways, using other senses, of identifying problems on a wastewater works.
  • Maintenance, cleaning and calibration of probes in own works.
  • Safety and emergency procedures when operating an activated sludge processes. 

  • UNIT STANDARD DEVELOPMENTAL OUTCOME 
    N/A 

    UNIT STANDARD LINKAGES 
    N/A 


    Critical Cross-field Outcomes (CCFO): 

    UNIT STANDARD CCFO IDENTIFYING 
    Identify and solve problems in which responses display that responsible decisions using critical and creative thinking have been made in relation to the activated sludge process by taking corrective actions relevant to the situation. 

    UNIT STANDARD CCFO WORKING 
    Work effectively with others as a leader of a team or group by assigning tasks and ensuring that tasks are carried out in terms of the required standards. 

    UNIT STANDARD CCFO ORGANISING 
    Plan, organise and manage oneself and one`s activities responsibly and effectively by prioritizing time in accordance with the task requirements. 

    UNIT STANDARD CCFO COLLECTING 
    Collect, analyse, organise and critically evaluate information relating to samples in order to optimize the process in an activated sludge plant. 

    UNIT STANDARD CCFO COMMUNICATING 
    Communicate effectively using visual, mathematical and/or language skills in the form of oral and/or written presentation by providing process information at shift hand-over and to his superiors by means of reports. 

    UNIT STANDARD CCFO SCIENCE 
    Use science and technology effectively and critically, showing responsibility towards the environment and health of others when dealing with nutrient removal. 

    UNIT STANDARD ASSESSOR CRITERIA 
    N/A 

    REREGISTRATION HISTORY 
    As per the SAQA Board decision/s at that time, this unit standard was Reregistered in 2012; 2015. 

    UNIT STANDARD NOTES 
    This unit standard replaces unit standard 12056, "Operate activated sludge process", Level 4, 18 credits.

    Integrated Assessment:

    When conducting assessments, assessors must ensure that they are familiar with the full text of the unit standards being assessed. Assessors must ensure that the assessment covers the specific outcomes, critical cross-field outcomes and essential embedded knowledge by developing assessment activities and tools, which are appropriate to the contexts in which the learners are working. These activities and tools may include self-assessment, peer assessment, formative and summative assessment. It may be more effective and efficient to assess a number of unit standards together in an integrated way, thus reducing the overall number of assessments and ensuring that commonalities that exist between a number of unit standards are captured in a way that makes sense for assessment.

    Assessment Option:

    Learners could be assessed using the following methods:
  • Oral or written questions.
  • Observation.
  • Product sample reports. 

  • QUALIFICATIONS UTILISING THIS UNIT STANDARD: 
      ID QUALIFICATION TITLE PRE-2009 NQF LEVEL NQF LEVEL STATUS END DATE PRIMARY OR DELEGATED QA FUNCTIONARY
    Elective  61709   Further Education and Training Certificate: Water and Wastewater Treatment Process Control Supervision  Level 4  NQF Level 04  Reregistered  2023-06-30  EWSETA 


    PROVIDERS CURRENTLY ACCREDITED TO OFFER THIS UNIT STANDARD: 
    This information shows the current accreditations (i.e. those not past their accreditation end dates), and is the most complete record available to SAQA as of today. Some Primary or Delegated Quality Assurance Functionaries have a lag in their recording systems for provider accreditation, in turn leading to a lag in notifying SAQA of all the providers that they have accredited to offer qualifications and unit standards, as well as any extensions to accreditation end dates. The relevant Primary or Delegated Quality Assurance Functionary should be notified if a record appears to be missing from here.
     
    1. AGB MATHE BUSINESS SERVICES 
    2. AMBROSER SOLUTIONS (PTY) LTD 
    3. BALOMAT SKILLS TRAINING ACADEMY 
    4. EECTRICAL CONTRACTORS ASSOCIATION - ECA 
    5. ESKOM DISTRIBUTION NORTH WESTERN REGION, BLOEMFONTEIN 
    6. GLERE SKILLS CONSULTANT 
    7. HIZONEX PTY LTD 
    8. INFINITE DIMENSION CONSULTING 
    9. INFRASTRUCTURE CONSULTING ENGINEERS CC 
    10. INGEN ENGINEERING PROJECTS 
    11. IQRAAM DEVELOPMENT CONSULTANCY (PTY) LTD 
    12. JOSMAP TRAINING INSTIUTE 
    13. Learn A Trade 
    14. MACT BUSINESS HUB 
    15. MARULENG TRAINING ACADEMY 
    16. MMESELANE CONSTRUCTION 
    17. MMTI 
    18. MOVING AHEAD DEVELOPMENT AGENCY 
    19. MPUMELELO CONSULTANCY CC 
    20. MUNICIPAL TRAINING & DEVELOPMENT INSTITUTE 
    21. NEW HOPE REVIVAL ORGANISATION 
    22. NKANYEZI FOUNDATION 
    23. NOKRAM (PTY) LTD 
    24. PERSEVCON CONSTRUCTION PTY LTD 
    25. PHAKGAMANG MATSIANA BUSINESS ENTERPRISE 
    26. Phathutshedzo Connsulting Training Provider 
    27. PRAXIS TRAINING AND CONSULTANCY (PTY) LTD 
    28. PROFESSIONAL DEVELOPMENT AND TRAINING INSTITUTE (PTY) LTD 
    29. PTDEV (PTY) LTD 
    30. Qualitas Training cc 
    31. ROCKWELL AUTOMATION 
    32. RONNELS CONSTRUCTION PTY LTD 
    33. SOUTHERN AFRICAN YOUTH MOVEMENT 
    34. TAG TEC TRAINING 
    35. YN2 TRADING AND PROJECTS 



    All qualifications and part qualifications registered on the National Qualifications Framework are public property. Thus the only payment that can be made for them is for service and reproduction. It is illegal to sell this material for profit. If the material is reproduced or quoted, the South African Qualifications Authority (SAQA) should be acknowledged as the source.