In line with legislation and environmental best practice, it’s crucial to prevent chemicals from entering non-target areas of a farm to protect the environment, public health, and biodiversity. Harmful chemicals can contaminate soil, water, and air, impacting crops and nearby ecosystems, and the effects are compounded when these chemicals enter non-target areas. Prevention is better than cure, and measures to prevent harmful chemicals from entering non-target areas will ensure continued sustainable farming practices.
A requirement of the SIZA Environmental Standard is adherence to the South African National Standard, SANS 10206: The handling, storage and disposal of pesticides. SANS 10206 requires that the mixing, filling, and storage area should be bunded with a floor made of non-porous material to contain spills and prevent contamination of the surrounding environment along with other sectional requirements, with the focus here being the alternatives to French drains/soak away systems.
Alternatives to French drain systems that are compliant with SANS 10206 include the following, which can be considered if changes or upgrades are necessary. Although it is not a SIZA requirement to specifically have the below in place, it is proposed as an alternative and a possible good practice to prevent hazardous substances from contaminating the surrounding area:
- Evaporation paddock/pit: The construction of an evaporation paddock includes the filling points having a floor of bunded non-porous material (waterproof cement or concrete). The sole purpose of this is to ensure that potentially contaminated run-off water does not contaminate the surrounding environment and evaporates as a means of disposal. The evaporation paddock/pit can either be filled with stones or covered by a metal grid to prevent animals or birds from drinking the contaminated water.
- Artificial wetland: An artificial wetland is a human-engineered or constructed ecosystem replicating natural wetlands hydrological, ecological, and biological characteristics. An artificial wetland can be used for water treatment, habitat restoration, or environmental conservation. An artificial wetland typically consists of carefully selected vegetation, substrate, and water flow management systems. A constructed artificial wetland aims to mimic the functions of natural wetlands by providing a habitat for pollutants, nutrients, and sediments from water through natural processes. Implementing an artificial wetland can assist with sustainable water management and wastewater treatment.
- Tank system: The French drain system can be redesigned, and a tank system can be installed to contain hazardous water from filling points; however, an accredited hazardous waste disposal company should remove the tank’s contents for proper disposal.
An important factor to consider when constructing an alternative is that storage dams containing wastewater may require registration or licencing in terms of the NWA. Where less than one (1) m3 of agri-industrial wastewater is legally disposed of in an on-site disposal facility (e.g. Evaporation paddock/pit, artificial wetland and tank system), no authorisation or registration is required, but evidence of the wastewater volume disposed of should be measured daily by using a water meter on the incoming line.
Other alternatives or combinations of the alternatives mentioned above can be used as long as the requirements set out in SANS 10206 and SIZA Environmental Standard are met. The SIZA Waste Management Guidelines provide information and assistance with waste management compliance for SIZA subscribers, and they are available on the MySIZA Platform. Additional queries can be made to the relevant personnel in the SIZA office at mattheww@siza.co.za or Tel 021 852 8184
