The Division of Engineering and Environmental Geology (DEEG) consists of 2 Subdivisions - Environmental
Geology which plays a leading role in the protection of vulnerable scarce natural resources such as water, soil and
biodiversity in the mining and related environment, and Engineering Geology subdivision deals with engineering geology/geological
hazards associated with various soil and rock formations throughout the country.
ENVIRONMENTAL GEOLOGY
This subdivision plays a leading role in the protection of vulnerable scarce natural resources such as water, soil and biodiversity the
mining environments through Investigate geochemical contamination emanating from mining and ore processing activities..
- This involves sampling mining environment; soils, stream sediments, vegetation, ground-and surface water, tailings, dust, PM10, PM2.5, etc
- Geochemical analysis of samples to determine contamination levels
- Interpretation of findings and generation of contamination distribution maps (see Conceptual Model below highlighting mine contamination hazard)
- Compiling Interpretative reports with recommendation to stakeholders (Compliance monitoring institutions, Mining operation, Local Authorities;
town council planners, and landowners)
KEY DIVISIONAL ACTIVITIES
- Soils contamination investigation
The Division regularly conducts Environmental Monitoring on mines to assess their potential to contaminate nearby environment. Soil
samples are collected from the mines and the surrounding areas and analysed at GSN Laboratories to evaluate the impact and extent of
Contamination from operations. The results are compared to Local and international standards and previous monitoring for any significant
change.
- Water Contamination Assessment
Water samples are collected in boreholes and surface water bodies in areas surrounding mine sites, and analysed for levels of geochemical contaminants.
- On-site parameters, i.e. pH, EC, Eh, and temperature
- Samples Taken:
- 1-litre PE bottle - major ion analyses,
- 250 ml PE bottle - for metal analyses
- 5-litre PE bottle - radionuclides
- SEMP for the Uranium province
The SEMP is an over-arching framework and roadmap to address the cumulative impacts of existing and potential developments, within
which individual projects have to be planned and implemented. Annual SEMP reports measure the performance around twelve Environmental
Quality Objectives (EQOs) and the extent to which uranium mining is impacting the uranium mining province (Central Namib). Each EQO
articulates a specific goal, provides a context, sets standards and elaborates on a number of key indicators that are monitored
Annual SEMP Report Link Annual SEMP Report
- Air Quality Management for the Uranium Mines in the Erongo Region
The Division is developing an overarching Air Quality Management Plan (AQMP) for the uranium Mining and other industries within the
Erongo Region with the aim of establishing mitigation measures that can be implemented by the various role players in a coordinated and
integrated manner. All sources of air pollution in the region are to be addressed, pollutants identified and quantified, and the
significance thereof determined.
A network of five (5) air quality monitoring stations have been established in the region with monitoring locations mainly focused
on the most populated areas in the region. Data, with regards to pollutants are recorded for Particulate Matter (PM10 and PM2.5), Radon
and meteorological conditions.
- Risk Assessment of Abandoned Mines
The division of Engineering and Environmental Geology under the Geological Survey of Namibia (GSN) conducts environmental risk assessments
of old abandoned mines across the country to determine which sites present a significant risk to safety, health and environment. The assessment
classifies sites into two main classes: Mining Environmental Liability (MEL) and Non - Mining Environmental Liability (Non-MEL). MEL sites have
significant impact on the environment and will require rehabilitation. So far the division established an inventory consisting of ca 200
abandoned mines, and is currently undertaking risk assessments associated with these sites.
ENGINEERING GEOLOGY
Engineering Geology Subdivision: deals with engineering geology/geotechnical problems/risks associated with different
various soil and rock formations throughout the country.
Key Activities
- To map and assess areas with geotechnical/engineering geology related problems and therefore to provide sound geotechnical advice to stakeholders.
- To generate geotechnical and geo-environmental data utilized in providing relevant advice to both the private sector and the general public.
- Operation of the Rock and soil mechanic laboratories
Engineering Geology Projects
Investigation of ground cracks in the Ohangwena region: Etale, Omakongo and Omutwe-woshimbungu Villages
The cracks in Ohangwena region resemble dropout sinkholes. Dropout sinkholes are formed in cohesive soil cover, where percolating rainwater has
washed the soil into stable fissures and caves in the underlying limestone. The clay in the sand makes the soil cohesive. Rapid failure of the
ground surface occurs when the soil collapses into voids that have been slowly enlarging and moving upwards while soil was washed into the limestone
fissures beneath.
Geo-hazard Mapping Survey of Windhoek
The division undertook a Geoengineering mapping Survey of the city of Windhoek with the aim of delineating zones of Geohazard potential. The Survey
produced three different maps of Geohazard zones, Vulnerability Items likely endangered and risk map which is a combination of the Geohazard zones and
Vulnerability zones. In and around the city limits of Windhoek, several Geoengineering instabilities related to Faults, Slope, Erosion gullies, Mudflows
and inundation were observed and should be considered in future developments.
Operation of Rock and Soil Mechanics Laboratory
