1. Plan and prepare for multiple aquifer production bores

1.1 Access, interpret and apply construct multiple aquifer production bores documentation and ensure the work activity is compliant

1.2 Obtain, read, interpret, clarify and confirm work requirements

1.3 Identify and address potential risks, hazards and environmental issues and implement control measures

1.4 Select and wear personal protective equipment appropriate for work activities

1.5 Discuss scope of work with client to gain general agreement on drilling plan

1.6 Obtain or sight any licences or permits required under the relevant State/Territory legislation or regulation.

1.7 Communicate and coordinate activities with others throughout the work activity

1.8 Obtain and interpret emergency procedures, and be prepared for fire/accident/emergency

1.9 Provide detailed strata logs, pump and development test results conducted during bore development and water and strata samples to the appropriate authorities

1.10 Complete all requirements for bore completion reports, decommissioning or abandonment and send to regulatory authorities within the time specified on bore licence

2. Design production bores for multiple aquifer systems

2.1 Determine most appropriate construction methods from the reading and interpretation of all available documented information and ensure relevant procedures and standards are adhered to

2.2 Design the bore to ensure the exclusion of unsuitable waters and to prevent the inter-mixing of aquifers with different water quality or Standing Water Levels

2.3 Select a bore site that will prevent contamination and minimise interference with other bores and that is safe with respect to potential occupational health and safety hazards

2.4 Select likely water entry mechanism from the formation to the bore such as open hole, slotted casing screens, gravel packs

2.5 Calculate appropriate artificial pack design parameters and recommended annular thicknesses required

2.6 Undertake calculations to determine appropriate screen design parameters (e.g. diameter, length, aperture size)

2.7 Plot and interpret sieve analysis results onto graphs

2.8 Select appropriate bore/surface casing for the anticipated ground/water quality and pressure conditions and any construction requirements

2.9 Ensure all necessary materials anticipated for the job are available and on site prior to commencement of construction phase

3. Construct production bores in multiple aquifer systems

3.1 Carry out any pre-start and start up procedures on plant or ancillary equipment

3.2 Identify, select and apply rig operational controls

3.3 Assemble and insert casing and screens

3.4 Grout or otherwise seal surface casing

3.5 Conduct grouting operations to seal intermediate and/or production casing strings or to seal selected zones

3.6 Construct bore in accordance with any applicable regulations, minimum construction and organisational requirements

3.7 Maintain plumbness and alignment of the hole within the required limitations

3.8 Collect, record and label formation and water samples

3.9 Maintain records accurately and legibly

3.10 Calculate hole, annular, fill or pack materials and mud pit volumes in cubic metres or litres

3.11 Select and place stabilising gravel fill as required

3.12 Determine appropriate artificial pack material grain size

3.13 Place artificial pack material in a manner that will ensure uniform distribution in the annular space without bridging

3.14 Maintain tool string inventories

3.15 Identify and protect headworks of the bore

3.16 Construct headworks to seal and cap the bore from surface water pollutants, environmental concerns and damage

3.17 Incorporate methods for measuring static and pumping water levels in headworks and for adequate sealing when not in use

3.18 Dispose of wastewater or hazardous materials from site and complete restoration of the bore site

4. Develop bore

4.1 Use development techniques with care to prevent collapsing of casing or screens

4.2 Use development techniques to improve hydraulic transmissivity around the bore

4.3 Undertake development until a continuous, clean supply of water is obtained, in accordance with site, contractual or regulatory requirements

4.4 Measure/calculate and record standing and drawdown water levels

4.5 Perform tests to estimate the sustainable yield of the bore

5. Disinfect/decontaminate bore and drilling equipment

5.1 Disinfect/decontaminate to comply with relevant standards or regulatory requirements

5.2 Handle hazardous chemicals in accordance with safety data sheets (SDS)

6. Carry out bore maintenance and rehabilitation

6.1 Carry out and shutdown procedures and secure equipment

6.2 Research all aspects of the bore construction and history

6.3 Undertake a process of diagnosis by testing and measurement to determine likely cause of bore deterioration

6.4 Devise a program of rehabilitation to ensure that the bore is restored to a reasonable condition

7. Decommission test/bore holes

7.1 Determine suitable decommissioning procedures and select appropriate sealing materials and placement methods

7.2 Carry out the decommissioning (abandonment) of test holes or bore holes in single and multiple aquifer systems

7.3 Seal bore with surface caps and cover borecap with 300mm local soil

7.4 Verify position/location of hole for future reference

7.5 Dispose of drill and other fluids safely