Dr Palesa Mohajane, a scientist production at the Department of Water and Sanitation in Hartbeespoort, was recently awarded her doctoral degree at the University of the Free State’s (UFS) autumn graduation ceremony. Her thesis, titled Modelling the effect of pandemic-induced burials on groundwater contamination: a hydrogeological and epidemiological assessment, looks at the impact of increased burial rates on groundwater quality.

Safeguarding groundwater resources

Dr Mohajane explains that witnessing the dramatic rise in burial rates during the COVID-19 pandemic – including instances of mass burials – and the resulting strain on cemeteries, raised concerns about the potential risk of groundwater contamination. This became a motivator for her research.

Her study bridges the gap between environmental science and epidemiology, developing tools to predict how disease outbreaks and related deaths can impact groundwater systems. “By focusing on this intersection, the study contributes knowledge that informs not only responsible cemetery management, but also the protection of groundwater resources important to public health,” she says.

Dr Mohajane highlights the environmental risks that come with an increase in burial activity during pandemics. “When death rates rise sharply, cemeteries experience a surge in burials, which accelerates decomposition within confined spaces. As bodies decompose, they release organic and inorganic pollutants, which can seep through geological layers and affect groundwater quality.”

She notes that if cemeteries are established without proper hydrogeological assessments, these substances can infiltrate the soil and contaminate water sources, posing a threat to both environmental and human health.

Using advanced tools to predict groundwater pollution

Dr Mohajane conducted her research during the post-pandemic period when the longer-term environmental effects of COVID-19-related burial practices began to surface. “Groundwater sampling and quality testing were conducted between September 2023 and January 2024. This period provided a suitable time frame to monitor contaminant release and assess the hydrochemical effects of the burial practices,” she explains.

Langberg Cemetery was selected as a case study due to its representative geological and human-made characteristics, making it a strong candidate for validating the research models. “This site allowed for real-world testing of the mathematical models and simulations, offering important insights into how contaminants move through soil and rock layers and impact groundwater,” says Dr Mohajane.

Her findings revealed that groundwater contamination is influenced by multiple interacting factors – including burial depth, body mass, and geological features. She explains that shallower burials allow pollutants to reach the water table more rapidly, while deeper burials may delay but not prevent eventual leaching. Larger body masses produce more decomposing material, increasing the number of pollutants released. Geological conditions such as fractures and varied rock formations also play a role in the spread of contaminants.

Dr Mohajane’s work has serious implications for both public health and water sustainability. The presence of elevated levels of total dissolved solids, electrical conductivity, specific ions, alkalinity, and mineralisation indicates potential health hazards. As groundwater is an important source of drinking water, she stresses the urgency of addressing these risks. “We need to use advanced tools to predict and prevent groundwater pollution before it occurs. With proper water management systems, we can reduce the environmental impact of pandemics,” she says.

She also emphasises the importance of continuous monitoring to detect pollutant levels that exceed safety limits. “Improving burial practices – including thorough geological assessments before establishing cemeteries and optimising burial depths – can help reduce contaminant migration. These measures are important to protect community water resources,” she adds.

Measures to protect groundwater and public health

Dr Mohajane’s research proposes a range of practical measures to safeguard groundwater and public health. Cemeteries should only be developed after detailed geological evaluations, and clear regulations must guide cemetery design to manage increased burial needs during pandemics. Regular water quality monitoring using modern detection tools is key, along with the inclusion of environmental assessments in public health planning.

“These policy measures, if adopted at both regional and national levels, can help to reduce the risk of groundwater pollution and support long-term public health,” she says.

Ultimately, this research supports South Africa’s efforts to protect its groundwater by encouraging collaboration between scientists and policy makers. It offers predictive tools, evidence-based guidelines for sustainable cemetery management, and highlights how scientific research can shape practical, effective policies. The goal is to ensure that groundwater remains a safe and secure resource during future public health and environmental crises.