Objectives

The primary objective of this tender is to drill and commission two (2) solar-powered boreholes in Limpopo, specifically at Maila Creche’ School and Maila Village in Makhado Ward 19. The project aims to establish sustainable water sources through borehole drilling, testing, and the installation of solar PV systems to ensure reliable water supply powered by renewable energy.

Scope

The scope of work includes:

• Site establishment and preparation for borehole drilling
• Conducting detailed geohydrological surveys and reports
• Drilling two boreholes up to 150 meters deep, with casing, capping, and concrete collars
• Performing borehole yield and water quality tests, including chemical and microbial analyses
• Design, supply, and installation of solar PV systems, including modules, controllers, pumps, grounding, and protection systems
• Construction of fencing around boreholes and solar systems
• Commissioning, testing, and documentation of all installed systems
• Obtaining necessary permits and approvals from local authorities prior to commencement

Technical Requirements

Site and Survey

• Initial site preparation and geophysical surveys using advanced instruments (PQWT, Proton Magnetometer)
• Survey report signed by a SACNASP-registered Natural Scientist, including instruments and methods used
• Selection of survey lines and borehole siting based on detailed geohydrological analysis

Borehole Drilling and Construction

• Drilling of 150m boreholes with 165mm diameter, compliant with SANS 10299-2003
• Steel casing: 12m length, 177mm x 3mm welded steel
• Concrete collar around borehole with specified dimensions and mixture (30 MPa strength)
• Installation of borehole caps and non-return valves to prevent contamination
• Drilling equipment suitable for diameters up to 254mm and various ground conditions
• Comprehensive borehole drilling report including depths, water levels, and casing details

Water Testing

• 48-hour yield tests including step drawdown, constant discharge, and recovery tests as per SANS 10299-4:2003
• Chemical and microbial analyses according to SANS 241-1:2015 standards, conducted at SANAS-accredited labs
• Tests include parameters such as EC, pH, TDS, coliforms, and other relevant water quality indicators

Solar PV System

• Installation of monocrystalline solar modules (555W x 6 modules per site), aligned true north, with tilt angles between 20-35 degrees
• Use of approved brands (e.g., Jinko Solar, Canadian Solar, etc.) with proper data sheets showing compliance
• Installation of a 2.2kW MPPT solar pump controller and submersible pump with appropriate flow and head specifications
• Grounding, surge protection, lightning arresters, and system earthing as per standards
• Mounting structures of galvanized steel, approximately 3.5m high, designed to withstand local wind conditions
• Electrical wiring, accessories, and protective enclosures compliant with IEC/SABS standards

System Commissioning and Warranties

• Full system testing, inspection, and documentation including single line diagrams, manuals, and warranties
• Electrical work to be performed by registered qualified electricians with valid certifications
• Warranties: 12 years for solar modules, 25 years linear power performance, minimum 1-year warranty for pumps and controllers, and 5-year structural support
• Provision of warranty certificates and comprehensive operation & maintenance manuals

Skills Requirements

• Qualified geohydrologists registered with SACNASP for site surveys and reports
• Experienced borehole drilling contractors familiar with SANS standards and groundwater development
• Certified electrical contractors or electricians registered with the Department of Labour for electrical installations
• Geomatics professionals (GPr or GTg) for survey line planning and site layout
• Laboratory accreditation for water quality testing (SANAS accredited labs)
• Qualified system installers with IEC/SABS compliance certification for solar PV and electrical systems
• Licensed fencing contractors for security fencing installation