The United Nations’ World Soil Day is held annually on the 5th of December and emphasises the importance of sustainable soil management. World Soil Day 2022 and its campaign “Soils: Where food begins” aims to focus attention on the importance of maintaining healthy ecosystems and human well-being by addressing the growing challenges in soil management, increasing soil awareness and advocating for the sustainable management of soil resources.
What is soil?
Soil can be defined as a mixture of organic matter, minerals, gases, liquids, and organisms that together support life. Soils are dynamic and diverse natural systems that lie at the interface between earth, air, water, and life. Developing gradually over time, soil is formed as the Earth’s surface naturally weathers and combines with decaying organic matter the exact structure and content influenced by elements such as climate, underlying geology, and activity from organisms above and below ground.
Why is soil health important?
Changing land use, pollution and the rapid advancement of agricultural technology and machinery, combined with increased demand for food, has put soils under immense pressure.
Soils need a balanced and varied supply of nutrients in appropriate amounts to be healthy. Nutrient depleted soils lose their capacity to support crops. Agricultural systems lose nutrients with each harvest, and if soils are not managed sustainably, fertility is progressively lost, and soils will produce nutrient-deficient plants.
Consequently, excess nutrient concentrations also pose a risk to soil health. Soils with excess nutrients can form a toxic environment to plants and animals. Runoff carrying excess nutrients from soil pollute waterways promoting the growth of algal blooms that can lead to eutrophication.
Today, 33% of land is moderately to highly degraded due to the erosion, salinization, compaction, acidification and chemical pollution of soils. Further loss of productive soils would severely damage food production and food security and amplify food-price volatility.
How we can help
To assess the extent of chemical pollution in soils Umvoto offers contaminated land assessments which include:
- Soil and Water Quality Assessments; and
- Waste Classification and Assessments.
Soil screening and monitoring
Soil testing and monitoring allows the assessment of soil health and extent of contamination by substances such as pesticides, heavy metals, hydrocarbons and other chemical pollutants with potential negative impacts on soil health, surface water or groundwater quality. Soil testing identifies potential contaminants and their concentrations in the soil and indicates whether the specific material can be re-used in site re-development. South African legislation governs soil assessments such as the South African Framework for the Management of Contaminated Land developed in line with NEM:WA (No. 59 of 2008), which outlines the methodology for the screening of potentially contaminated sites to provide a risk-based decision support assessment protocol. In addition, the Department of Forestry, Fisheries and the Environment gazetted the GN 331: National Norms and Standards for the Remediation of Contaminated Land and Soil Quality in May 2014, providing Soil Screening Values (SSVs), a tiered system for priority soil contaminants, facilitating relevant receptor sensitivity which could be subject to exposure. These SSVs are defined as:
- SSV1: Protective of both human health and aquatic ecosystem health, and not land-use specific; and
- SSV2: Protective of human health where protection of water resources is not an applicable pathway for consideration and are land-use specific: including informal residential, standard residential and commercial/industrial land uses.
In situations where topsoil is severely contaminated, the topsoil will need to be stripped, bunded and disposed of appropriately. The classification of waste allows waste types to be identified for the separation of materials, which may need to be sent off to different types of landfills based on their risk. South African legislation guides waste classifications and assessments, listed as follows:
- NEM:WA (No. 59 of 2008) Government Notices (23 August 2013):
- R.634 Waste classification and Management Regulations;
- R.635 National norms and standards for the assessment of waste for landfill disposal; and
- R.636 National norms and standards for disposal of waste to landfill.
- The National Environmental Management: Waste Amendment Act (NEM:WAA; No. 26 of 2014) (2 June 2014):
- NEM:WA (No. 59 of 2008) GN R.715 Regulations Regarding the Exclusion of a Waste Stream or a Portion of a Waste Stream from the Definition of Waste (18 July 2018); and
- NEM:WA (No. 59 of 2008) GN 85 of 2020, Notice Indicating the Exclusion of Certain Waste Streams or Portions of Waste Streams from the Definition of Waste for Beneficial Use (03 February 2020).
Appropriately assessing contaminated land allows for appropriate remediation recommendations, which aids in the sustainable management of soil resources and achieving World Soil Day 2022’s campaign of “Soils: Where food begins”.
If you would like to learn more about contamination assessments, please feel free to contact us on firstname.lastname@example.org or 021 709 6700.