63 Wessel Road, Rivonia, Sandton



Harmony Vaal Operations & MOAB GW Services

During 2022 GCS (Pty) Ltd was appointed by Harmony Gold (Pty) Ltd to act as an independent groundwater consultant to update the numerical groundwater flow and transport model for their operations. This was a follow-up on the previous reports and model calibration processes completed from 2008 to 2019. The report is based on a description of the design and application of the existing VR, MK, Mine Waste Solutions (MWS) and the Great Noligwa (NG) regional groundwater models (GCS, 2019) and the methods that were applied to calibrate the model. This included :
• Data Review
• Update Hydrogeological and Geological Conceptual model
• Groundwater Numerical Flow and Transport Modelling

Soil Assessment for the Modikwa Platinum Mine

Location: Burgersfort, Mpumalanga Province.

During 2021 GCS was appointed by Modikwa Platinum Mine to undertake a soil quality assessment for the Modikwa Platinum Mine. The main objective of the study was to sample the 5 stockpiles, and reference sites to determine the inherent soil quality of the stockpiles vs the reference sites and the suitability of the soils for rehabilitation purposes. The scope of work included:
• Field investigation: GCS undertook soils sampling of the 5 stockpiles, and reference samples upstream/downstream of the stockpiles. Sample positions were recorded with a handheld Global Positioning System (GPS).
• Soil chemistry assessment: Soil samples were submitted to Eco Analytica (based at the Potchefstroom University) for analytical analyses.
• Soil chemistry data was assessed in context to the site, and the
• nutrient content was determined.
• Mapping & reporting the stockpiles. Sample positions were recorded with a handheld Global Positioning System (GPS).
• Soil chemistry assessment to determine nutrient content.
• Mapping & reporting


Geohydrological Assessment for Tronox Central Processing Operations

Location: Empangeni, KZN
During 2021 GCS (Pty) Ltd was appointed by Tronox KZN Sands (Pty) Ltd (Tronox) to compile responses to a pre-compliance notice that was issued to Tronox after a joint inspection was conducted at the site by the King Cetshwayo District Municipality, Department of water affairs and sanitation (DWS), the Provincial Department of Economic Development, Tourism and Environmental Affairs (DEDTEA) and the Department of Environmental Affairs, Fisheries and Forests (DEAFF) in November 2018. A geohydrological assessment was one of the specialist studies committed to by Tronox. This report forms part of the response to the Department and covers Phase 6 of the required specialist studies. Scope of Work: • Desktop study and Data Review
• Field investigation
o A hydrocensus (within a 2.5km radius of the proposed underground and opencast areas) was undertaken in the study area to identify groundwater users.
o Several geophysical profile lines using the electromagnetic, Electrical Resistivity Tomography (ERT) and magnetic methods
o Drilling supervision of several monitoring boreholes
o Water sampling of hydrocensus boreholes
• Hydrogeological and geological conceptual Model development
• Groundwater numerical flow and transport modelling
• Hydrogeological risk assessment
• Monitoring plan

Square Kilometre Array (SKA)

Location: Meerkat National Park, Northern Cape, South Africa
Project: SKA (Square Kilometre Array) The history of the SKA dates to the 1990's with an international effort to build the world’s largest and most sensitive radio telescope to help better understand the history of the universe. The SKA is proposed to be constructed in two phases: • Phase 1 (called SKA1) in South Africa and Australia, and
• Phase 2 (called SKA2) expanding into SKA Africa partner countries (Botswana, Ghana, Kenya, Madagascar, Mauritius, Mozambique, Namibia and Zambia), with the component in Australia also being expanded. Phase 1 of the SKA mid-frequency dish array is currently being constructed in South Africa (SKA1_MID). The entireSKA1_MID footprint (covering approximately 627 857ha) consists of:
1) A core area which is land owned by the National Research Foundation (NRF) and includes the MeerKAT radio telescope; and
2) 3 Spiral Arms consisting of dish-antenna extending out to120km each. PSKA1_MID consists of an array of 197 dish-antennas, incorporating the MeerKAT, and associated infrastructure.
GCS has offered a one-stop shop for the South African Radio Astronomy Observatory (SARAO). Since 2015 to date GCS has offered the following services to the South African Radio Astronomy Observatory (SARAO).
• Water Unit:
o Stormwater Management Plans.
o Hydrological Assessments
(including flood lines for the greater area)
o Hydrogeological Assessments (yield & quality testing).
• Geotechnical Unit:
o Geotechnical Investigations.
• Environmental Unit:
o Aquatic Assessments.
o General Authorisations
o Water Use License Applications.
• GIS Unit:
o Over 100 maps have been made by the GIS team.


Pit Groundwater Model, Dewatering and River Diversion

During 2022 GCS (Pty) Ltd was appointed by Reminex (PTY) Ltd to conduct a hydrogeological assessment at a gold mine in Guinea. The aim of the investigation was to assess the efficiency of the current dewatering network and predict dewatering scenarios with the pit expansion. Additionally, a flood protection study was conducted to assess multiple river diversion options around the existing pit.

Scope of Work:
• Development groundwater model to simulate dewatering scenarios
• Review dewatering system to suit the design of a 1600 USD/Oz pit
• Review the water balance for 2.8 Mtpa and predict future water balance with increased capacity to 3.3Mtpa
• Review the position of existing dewatering boreholes and recommend additional dewatering boreholes
• Flood protection study of the 1600 USD/Oz pit

Lephalale Solar Energy Facility

During 2021 and 2022 GCS conducted the Application for Environmental Authorisation for the proposed 70MW photovoltaic solar energy facility near the town of Lephalale in the Limpopo Province. The application required the completion of an Environmental Impact Assessment in accordance with the National Environmental Management Act (Act No. 107 of 1998): Environmental Impact Assessment Regulations (2014), as amended as well as the Water Use Licence Application in accordance with the National Water Act (Act No. 36 of 1998).


Tharisa Minerals Pit Lake Study

During 2022-2023 GCS conducted the Amendment Application of the Environmental Management Programme for the Tharisa Platinum Mine to facilitate the establishment of a pit lake in the open cast excavation at the mine as a rehabilitation option. The scope of works made provision for the completion of a Groundwater Model, a Geochemistry Model for the proposed pit lake, a Hydrological Assessment of the surface infrastructure and the incorporation of the generated information into the amended Environmental Management Programme for submission to the authorities. Provision was also made for a regulated public participation process