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: 

Evaluate the stability of pillars in underground mining 
SAQA US ID UNIT STANDARD TITLE
256901  Evaluate the stability of pillars in underground mining 
ORIGINATOR
SGB Mining and Minerals 
PRIMARY OR DELEGATED QUALITY ASSURANCE FUNCTIONARY
-  
FIELD SUBFIELD
Field 06 - Manufacturing, Engineering and Technology Fabrication and Extraction 
ABET BAND UNIT STANDARD TYPE PRE-2009 NQF LEVEL NQF LEVEL CREDITS
Undefined  Regular  Level 4  NQF Level 04 
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 does not replace any other unit standard and is not replaced by any other unit standard. 

PURPOSE OF THE UNIT STANDARD 
This unit standard will be useful for people who are pursuing a career in Rock Engineering.

This unit standard is intended to promote general skills and knowledge of evaluating the stability of pillars in the mining and minerals sector in order to ensure knowledgeable and informed workers.

People credited with this unit standard are able to:
  • Demonstrate an understanding of the factors that influence the stability of pillars.
  • Evaluate the stability of pillars from scrutiny of plans.
  • Evaluate the stability of pillars from underground observations.
  • Record, report and communicate results of the evaluation of pillar stability. 

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

  • UNIT STANDARD RANGE 
    N/A 

    Specific Outcomes and Assessment Criteria: 

    SPECIFIC OUTCOME 1 
    Demonstrate knowledge and understanding of the factors that influence the stability of pillars. 

    ASSESSMENT CRITERIA
     

    ASSESSMENT CRITERION 1 
    The expected pillar behaviour for various types of pillars is described using neat, annotated sketches. 
    ASSESSMENT CRITERION RANGE 
    Range must include:
  • Crush pillars.
  • Non-yield pillars.
  • Yield pillars.
  • Bracket pillars.
  • Boundary pillars.
  • Stabilizing pillars.
  • Water barrier pillars.
     

  • ASSESSMENT CRITERION 2 
    The factors that affect regular instope pillar behaviour are listed and explained in the context of mining operations. 
    ASSESSMENT CRITERION RANGE 
    Range must include:
  • Pillar dimensions.
  • Extraction ratio.
  • Width: Height ratio.
  • Rock strength.
  • Depth/Loading.
  • Extent of mining.
     

  • ASSESSMENT CRITERION 3 
    The factors that affect regional pillar behaviour are listed and explained in the context of mining operations. 
    ASSESSMENT CRITERION RANGE 
    Range must include:
  • Stope closure.
  • Stope back length.
  • Propensity for strong ground motion.
  • Energy release rates.
  • Shear strength of discontinuity planes.
  • Pillar size.
  • Pillar continuity.
  • Pillar loading.
     

  • ASSESSMENT CRITERION 4 
    The concept of safety factor as applied to pillars and the components used to calculate the safety factor is explained in the context of mining operations. 

    SPECIFIC OUTCOME 2 
    Evaluate the stability of pillars from scrutiny of plans. 

    ASSESSMENT CRITERIA
     

    ASSESSMENT CRITERION 1 
    Plans required to perform pillar scrutiny are appropriately chosen in terms of legal and operational requirements. 
    ASSESSMENT CRITERION RANGE 
    Range must include:
  • Workable scale.
  • Composite of face positions and geology.
  • Peg numbers indicated.
  • Stoping widths indicated.
     

  • ASSESSMENT CRITERION 2 
    The plan dimensions of pillars are measured and compared to the designed dimensions. 

    ASSESSMENT CRITERION 3 
    Nonstandard pillar cutting is noted using mine specific methods. 
    ASSESSMENT CRITERION RANGE 
    Range must include:
  • Demarcation on the plan.
  • Recordings on sheets.
  • Computer programmes.
     

  • ASSESSMENT CRITERION 4 
    The width: height ratio of pillars are calculated and appropriately recorded in terms of the relevant procedure. 

    ASSESSMENT CRITERION 5 
    The occurrence of major geological features within or in close proximity to pillars is evaluated to assess optimum pillar(s) size and the information is appropriately noted in accordance with legal and operational requirements. 

    SPECIFIC OUTCOME 3 
    Evaluate the stability of pillars from underground observations. 

    ASSESSMENT CRITERIA
     

    ASSESSMENT CRITERION 1 
    The dimensions of the pillars are measured (where practical) and compared to the designed dimensions of the pillars in terms of the relevant procedure. 

    ASSESSMENT CRITERION 2 
    The stress fracturing in the pillar and the dimensions of the intact pillar core are noted and evaluated against the required fractured state of the pillar in terms of the relevant procedure. 

    ASSESSMENT CRITERION 3 
    Pillar failures are noted with respect to the position of failure within the pillar and the site of failure on the mining lease in terms of the relevant procedure. 
    ASSESSMENT CRITERION RANGE 
    Range must include:
  • Indentation (punching).
  • Poisson's effect.
  • Shear of weak layers or planes.
  • Bursting.
     

  • ASSESSMENT CRITERION 4 
    The influence that the pillar has on the immediate rock mass peripheral to the pillar is noted in terms of the relevant procedure. 
    ASSESSMENT CRITERION RANGE 
    Range must include:
  • Guttering.
  • Dislocation of discontinuities.
  • Heave of footwall/floor.
  • Shear failure of bords between pillars.
  • Dilation.
     

  • SPECIFIC OUTCOME 4 
    Record, report and communicate results of the evaluation of pillar stability. 

    ASSESSMENT CRITERIA
     

    ASSESSMENT CRITERION 1 
    Observations and evaluations made of pillars are recorded and presented in accordance with mine specifications. 

    ASSESSMENT CRITERION 2 
    The relevant personnel are informed of the results of the evaluations effectively and timeously in terms of the relevant procedure. 

    ASSESSMENT CRITERION 3 
    The consequences of not communicating the results of pillar stability evaluations are explained in terms of legal and operational requirements. 


    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 Education, Training, Quality, Assurance (ETQA) Body, or with an ETQA that has a Memorandum of Understanding 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 Education, Training, Quality, Assurance (ETQA) Body, or with an ETQA that has a Memorandum of Understanding with the relevant ETQA.
  • Assessment and moderation of assessment will be overseen by the relevant Education, Training, Quality, Assurance (ETQA) Body, or with an ETQA that has a Memorandum of Understanding with 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, unless ETQA policies specify otherwise.
  • Anyone wishing to be assessed against this unit standard may apply to be assessed by any assessment agency, assessor or provider institution that is accredited by the relevant ETQA. 

  • UNIT STANDARD ESSENTIAL EMBEDDED KNOWLEDGE 
    The following essential embedded knowledge is addressed in an integrated way in the unit standard:

    Knowledge that the assessor will evaluate:
  • The factors that influence the stability of pillars.
  • The expected pillar behaviour for various types.
  • The factors that affect regular instope pillar behaviour.
  • The factors that affect regional pillar behaviour.
  • The concept of safety factor as applied to pillars.
  • The components used to calculate the safety factor is explained.
  • Evaluating the stability of pillars from scrutiny of plans.
  • Evaluating the stability of pillars from underground observations.
  • Recording, reporting and communicating results of the evaluation of pillar stability.

    Causes and effects (Occupational Health and Safety):
  • Use of equipment.
  • Use of personal protective equipment.
  • Adherence to occupational health and safety requirements.
  • Work related hazards and associated risks.

    Regulations, legislation, agreements, policies and standards:
  • Occupational health, safety and environmental legislation and regulations.
  • Quality policies, standards and agreements. 

  • UNIT STANDARD DEVELOPMENTAL OUTCOME 
    N/A 

    UNIT STANDARD LINKAGES 
    N/A 


    Critical Cross-field Outcomes (CCFO): 

    UNIT STANDARD CCFO IDENTIFYING 
    Identify and solve problems and make decisions using critical and creative thinking.

    Note:
  • The use of knowledge and understanding of pillar behaviour for conducting evaluations of pillar stability. 

  • UNIT STANDARD CCFO WORKING 
    Work effectively with others as members of a team, group, organisation or community.

    Note:
  • The ability to organise a pillar evaluation exercise. 

  • UNIT STANDARD CCFO ORGANISING 
    Organise and manage themselves and their activities responsibly and effectively.

    Note:
  • The ability to systematically organise and coordinate a programme of pillar evaluation. 

  • UNIT STANDARD CCFO COLLECTING 
    Collect, analyse, organise and critically evaluate information.

    Note:
  • The ability of the learner to collect information and use this information to evaluate the stability of pillars. 

  • UNIT STANDARD CCFO COMMUNICATING 
    Communicate effectively, using visual, mathematical and/or language skills in the modes of oral and/or written presentations.

    Note:
  • The use of neat annotated sketches and simple data capture sheets confirms understanding. 

  • UNIT STANDARD CCFO SCIENCE 
    Use science and technology effectively and critically showing responsibility towards the environment and health of others.

    Note:
  • The use of photogammetry to quicken and proactively manage pillar cutting. 

  • UNIT STANDARD CCFO DEMONSTRATING 
    Demonstrate an understanding of the world as a set of related systems by recognising that problem-solving contexts do not exist in isolation.

    Note:
  • The ability to relate pillar stability to the stability of not only isolated workings but also the entire operational lease. 

  • 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 
    Terminology:

    Specified Rewuirements:

    Specified requirements include legal and site-specific requirements and are contained in one or more of the following documents:

    Legal:
  • Relevant Acts: e.g. Mine Health and Safety Act, 1996 (Act no 29/1996), and Minerals Act and Regulations, 1991 (Act no 50/1991).
  • Mandatory Codes of Practice.
  • SABS and other relevant Standards.
  • Chief Inspector of Mines' Directives.

    Site-Specific:
  • Hazard Identification and Risk Assessments (HIRA).
  • Occupational Health and Safety Risk Management Programme.
  • Managerial Instructions.
  • Mine Standard Procedures.
  • List of Recorded OH and S Risks.
  • Working Guides.
  • Equipment and Materials Specifications. 

  • QUALIFICATIONS UTILISING THIS UNIT STANDARD: 
      ID QUALIFICATION TITLE PRE-2009 NQF LEVEL NQF LEVEL STATUS END DATE PRIMARY OR DELEGATED QA FUNCTIONARY
    Elective  62796   Further Education and Training Certificate: Strata Control Operations  Level 4  NQF Level 04  Reregistered  2023-06-30  MQA 


    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.
     
    NONE 



    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.