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Follow the links below to find material targeted to the unit's elements, performance criteria, required skills and knowledge

Elements and Performance Criteria

1. Plan and prepare for the construction of artesian (flowing) aquifer bores
   • Obtain, interpret and confirm work requirements
   • Access, interpret and apply artesian (flowing) aquifer bores construction documentation and confirm work activity is compliant
   • Identify hazards and environmental issues, assess the risks and implement control measures in line with workplace procedures
   • Select and wear personal protective equipment required for work activities
   • Communicate with other personnel at site according to work requirements and confirm briefings and handover details are communicated and received
   • Discuss scope of work with client and give technical advice, cost structure, workmanship warranty, quantity and quality of materials, construction standards and methods to be used and gain general agreement on drilling plan
   • Complete required reports and provide reports, samples and strata logs, pump and development test results to relevant authorities as required
2. Design bores for artesian aquifer systems
   • Determine required construction methods and drilling fluid program according to down-hole conditions and anticipated pressures
   • Design bore according to environmental and work requirements
   • Select a bore site that will prevent contamination and minimise interference with other bores
   • Select likely water entry mechanism from the formation to the bore including open hole, slotted casing screens, gravel packs
   • Calculate required artificial pack design parameters, and recommended annular thicknesses required
   • Undertake calculations to determine appropriate screen/slot design parameters, including for diameter, length, aperture size
   • Select required bore/surface casing types, size, strength and wall thicknesses for the anticipated ground/water quality and pressure conditions and any construction requirements
   • Confirm all necessary materials anticipated for the job are available and on site prior to commencement of construction phase
3. Construct bores in artesian aquifer system
   • Carry out any pre-start and start up procedures according to manufacturer specifications and workplace procedures
   • Select, slot, assemble and insert casing and screens suitable for the formations in which they are deployed
   • Select, mix and place grout or seal surface according to legislative and company requirements and manufacturer specifications
   • Construct bore according to legislative requirements and workplace procedures
   • Use, maintain, test and record nontoxic, removable drilling fluids and additives according to manufacturer specifications and environmental requirements
   • Maintain plumbness and alignment of the hole within the required limitations and carry out a plumbness test where required
   • Prepare for and recognise any symptoms of a formation kick and take action to control the bore
   • Collect, store, record, label and transport formation and water samples according to licensing requirements
   • Arrange for geophysical logging tools to be run in bore if required
   • Determine aquifer formation grain size distribution from sieve analysis and interpret appropriate gravel pack and screen slot aperture dimensions for gravel packed wells
   • Select and place artificial pack materials
   • Remove drilling fluids from the bore to allow subsequent development
   • Maintain tool string inventories according to workplace procedures
4. Construct bore headworks
   • Construct headworks for bore including isolation valves to retain/control artesian flow and to permit independent testing of both pressure and flow without interference to reticulation system
   • Identify and protect headworks of the bore
   • Construct headworks to seal and cap the bore from surface water pollutants, environmental concerns and damage
   • Dispose of and neutralise wastewater or hazardous materials from site as required and complete restoration of the bore site camp facilities
   • Use development techniques with care to prevent collapsing of casing or screens
   • Undertake development until a continuous, clean supply if water is obtained according to site, contractual and regulatory requirements
   • Measure/calculate and record standing and drawdown water levels
   • Perform pump and/or development tests to estimate the sand content and sustainable yield of the bore
5. Disinfect/decontaminate bore and drilling equipment
   • Determine and monitor potential contaminants of drilling equipment
   • Disinfect and decontaminate bores and installed equipment constructed for potable supplies as required
6. Carry out bore maintenance and rehabilitation
   • Carry out and shutdown procedures and secure according to manufacturer specifications and workplace procedures
   • Undertake a process of diagnosis to determine likely cause of bore deterioration
   • Devise a rehabilitation program according to environmental requirements
   • Determine suitable decommissioning procedures and select required materials
   • Carry out the decommissioning (abandonment) of artesian aquifer bores
   • Place cement bridges at the top of the surface casing and at the surface casing shoe
   • Verify position/location of hole for future reference
   • Dispose of drill and other fluids safely according to environmental requirements and workplace procedures
   • Record entire decommissioning procedure and details of bore cementing according to workplace procedures
   • Complete bore completion report and submit to State/Territory Water Authority
   • Carry out housekeeping requirements according to workplace procedures

Performance Evidence

The candidate must demonstrate the ability to complete the tasks outlined in the elements, performance criteria and foundation skills of this unit, including evidence of the ability to:

construct artesian (flowing) aquifer bores on at least two occasions, including:

designing the bore to ensure the exclusion of unsuitable waters

identifying and applying appropriate headworks design for class 3 bore applications

selecting a bore site to prevent contamination and minimise interference with other bores

selecting a water entry mechanism from the formation to the bore, including:

open hole

slotted casing screens

gravel packs

assembling and inserting casing and screens

selecting, mixing and placing grout or otherwise seal surface casing from 10 m into competent impermeable strata and back to the surface with a minimum sheath thickness of 20mm above maximum shoe of coupling joint diameter size

grouting to seal intermediate and/or inner production casing strings with a 15mm minimum thickness grout sheath or to seal selected zones so that the water from the production bore is drawn from one primary formation only (unless otherwise allowed by the permit)

maintaining, testing and recording fluid properties including viscosity, mud weight, filtration and sand content

maintaining plumbness and alignment of the hole

developing the bore until a continuous, clean supply of water is obtained

testing pumps and developments to estimate the sand content and sustainable yield of the bore.

During the above, the candidate must:

locate and apply relevant standards, legislation, documentation, policies and procedures

implement the requirements, procedures and techniques for constructing artesian (flowing) aquifer bores, including:

selecting and wearing required personal protective equipment

plotting and interpreting sieve analysis results onto graphs preventing the inter mixing of aquifers with different water quality and/or Standing Water Level

communicate clearly and concisely with clients, co-workers and management to receive and clarify work instructions and coordinate work activities prior to commencing

comply with written and verbal reporting requirements and procedures work.

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Knowledge Evidence

The candidate must be able to demonstrate knowledge to complete the tasks outlined in the elements, performance criteria and foundation skills of this unit, including knowledge of:

key legislation required to construct artesian (flowing) aquifer bores

key policies, procedures and established requirements for constructing artesian (flowing) aquifer bores, including those for:

Minimum Construction Requirements (MCR)

work health and safety

environmental issues

accidents and emergencies

safety data sheets (SDS)

fishing operations in regard to types of drilling being undertaken

housekeeping

key site information, including:

basic geological formations which permit groundwater movement, including soil and rock classifications

factors affecting groundwater quality for aquifer systems, including drillability and stability

key factors affecting work activities described in performance evidence above, including:

objectives of bore development

equipment characteristics, technical capabilities and limitations

safety hazards and sources of contamination when siting a bore

the necessity of having a signed agreement/contract with the client

the appropriate casing materials for various applications

wire-wound screens

drilling fluids, including testing and conditioning

grout placement methods and procedures including pressure grouting

results of sieve analysis

applications for natural pack, stabilising fill and artificial pack completion techniques

screen design parameters to ensure appropriate entrance velocities

characteristics of ‘good samples’ required for water well construction

ways in which sampling errors can occur

types of pathogens and contaminants including bacteria

key calculations for constructing artesian (flowing) aquifer bores, including those for:

hole, annular fill or pack materials and mud pit volume in cubic metres or litres

required artificial pack design parameters and recommended annular thickness required

appropriate screen/slot design parameters, including for diameter, length, aperture size.

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