Objectives

The primary objective of this tender is to conduct comprehensive hydrogeological investigations at Corndale Farm Trust in the Eastern Cape, including borehole siting, drilling, and testing. Specifically, the project aims to identify suitable groundwater sources through detailed surveys, establish boreholes up to 100 meters deep, and perform yield and water quality tests to ensure sustainable water extraction in compliance with relevant standards.

Scope

The scope of work encompasses the following phases:

• Phase 1: Water Survey – Site establishment, geophysical surveys, and hydrogeological reporting to identify potential borehole locations.
• Phase 2: Borehole Drilling, Casing, and Capping – Drilling of 4 boreholes to 100 meters, installation of steel casings, and sealing with caps.
• Phase 3: Borehole Yield and Water Tests – Conducting 48-hour yield tests, chemical and microbiological water quality tests, and obtaining necessary certifications.

Technical Requirements

The technical specifications include:

Phase 1: Water Survey

• Preparation of the site for drilling activities.
• Geohydrological surveys using advanced geophysical instruments such as Pulse Quick Wavelet Transform (PQWT) and Proton Magnetometer, with surveys spanning 200 meters at 5m intervals.
• Survey reports must be signed by a SACNASP-registered Natural Scientist and include details of instruments and methods used.
• Survey results determine whether drilling proceeds; no drilling if groundwater is not available.

Phase 2: Borehole Drilling

• Drilling of 4 boreholes, each 100m deep with a 165mm diameter, following SANS 10299-2003 standards.
• Installation of 12m steel casings (177mm x 3mm), welded sequentially during lowering.
• Provision of borehole caps to prevent contamination.
• Use of appropriately sized drilling equipment capable of handling diameters up to 254mm and varying soil conditions.
• Comprehensive borehole drilling logs documenting depths, diameters, water levels, and casing details.
• Provision for abandonment of unsuccessful boreholes, with costs adjusted accordingly.

Phase 3: Yield and Water Testing

• 48-hour yield tests including step drawdown and constant discharge tests, with water level recovery monitoring.
• Compliance with SANS 10299-4:2003 standards, with certification issued upon successful testing.
• Water quality testing for chemical and microbiological parameters according to SANS 241-1:2015 standards, conducted at SANAS-accredited laboratories.
• Tests include parameters such as EC, pH, TDS, turbidity, coliforms, and various chemical constituents.

Skills Requirements

• Registered Natural Scientist with SACNASP for hydrogeological surveys and report sign-off.
• Experienced geophysicists proficient in advanced geophysical survey techniques (PQWT, Proton Magnetometer).
• Qualified drilling contractors with capacity to operate drilling equipment suitable for groundwater boreholes up to 100 meters deep.
• Certified laboratory services for water quality testing, compliant with SANAS accreditation standards.
• Project management skills to coordinate site preparation, drilling, testing, and reporting activities efficiently.