Objectives

The primary objective of this tender is to conduct a comprehensive borehole assessment, survey, drilling, and equipping at the Glen Bull Test Centre. The project aims to establish the feasibility of drilling and installing a borehole, including site selection, water availability analysis, risk assessment, and water quality testing. The assessment will inform the sustainable yield and operational capacity of the borehole for irrigation and human consumption purposes.

Scope

The scope encompasses all activities necessary for the successful completion of the borehole project, including:

• Site analysis and selection
• Hydrological and geological survey
• Drilling of a 165 mm borehole in mixed geological formations
• Installation of 177 mm steel casing where required
• Yield testing through blow yield determination, step drawdown tests, and long-duration constant discharge tests
• Water level recovery measurements post-testing
• Installation of borehole equipment including submersible motor and pump, power supply cabling, PVC casing, gravel pack, and associated fittings
• Water quality testing for potable use, including physical, chemical, and microbiological parameters
• Preparation of comprehensive reports including drilling logs, yield tests, hydrogeological assessments, and water quality analysis
• Supervision and reporting by qualified hydrogeologists

Technical Requirements

The technical specifications for the project include:

• Use of a 165 mm borehole with installation of 177 mm steel casing as needed
• Blow yield determination and step drawdown tests (6 × 1-hour steps)
• 18-hour constant discharge test and 2-hour recovery test
• Water level measurement immediately after pump shutdown and recovery until within 10% of static water level
• Long duration tests (minimum 12 hours, extendable up to 30 days) for sustainable yield estimation
• Compliance with South African National Standard SANS 10299-4:2003 for test pumping
• Installation of submersible pump and motor powered by 220 V supply, with appropriate cabling and safety measures
• Installation of PVC casing with filter gravel and gravel-pack filtration system
• Provision of electrical certificates of compliance and weatherproof enclosures
• Water quality testing adhering to SANS 241 standards
• Preparation of detailed reports and documentation

Skills Requirements

The tender mandates the engagement of qualified professionals with the following skills and credentials:

• Hydrogeologists/Geohydrologists: Must be registered professionals with SACNASP certification, responsible for borehole yield assessments and water quality testing.
• Geologists: To assist in site analysis and geological assessments.
• Technical personnel: Skilled in drilling operations, equipment installation, electrical wiring, and safety standards.
• Laboratory technicians: Certified to perform water quality tests in accordance with SANS 241.
• Project management and supervision: Experienced in overseeing drilling projects, ensuring compliance with standards, and compiling technical reports.

Additionally, bidders must demonstrate experience with similar borehole projects, provide references, and hold appropriate CIDB contractor grading (minimum 1 CE and ME or higher).