Articles

A Technical Guide
for Wine Producers

RECENT ARTICLES | WYNBOER HOME

Proposed IPW criteria for managing wastewater, solid waste, noise and air pollution

Lourens van Schoor, Environmental Manager, ARC Infruitec-Nietvoorbij, Stellenbosch
Introduction
The most important elements at wine cellars which can result in negative impacts on the environment include wastewater, as well as solid waste such as skins, pips, stems, lees, used filter material and sedimentation substances and should therefore be included in the system for integrated production of wine (IPW). Pumps, refrigeration units, compressors and conveyors all entail the risk of noise and air pollution. Wastewater can cause salination and eutrofication of water resources such as natural streams, rivers, dams, ground water and wetlands. Furthermore, it can result in soil degradation such as salination, waterlogging, chemical contamination, erosion and destruction of soil structure. These impacts will be increased by factors such as electrical or process interruptions, fires, floods, storms, overloading/underloading of wastewater catchment dams, temporary unavailability of wastewater catchment dams and trained operators. Solid waste, on the other hand, causes bad odours in particular and may contaminate soil and water resources, thus having possible negative effects on vegetation and its performance. To manage these aspects and impacts efficiently, it is important for cellar managers to follow IPW guidelines for this. The South African IPW system is in fact the only IPW-system worldwide that also includes cellar practices. It is important therefore for the South African wine industry to ensure that these aspects are being addressed efficiently. It is planned to incorporate the following criteria, which are based on the most recent research results published worldwide, as well as national environmental legislation, in the IPW-system. Table 1 indicates the scoring method for these aspects using the IPW-points scale. The evaluation of the total IPW-points scale will be adjusted to incorporate these guidelines. This will also mean that management of wastewater, solid waste, noise and air pollution will score more points in comparison with the existing IPW-points scale and only criteria for good, bad or disqualification will be used in this regard. The complete and updated guidelines will soon be sent to all wine cellars.
Wastewater management: monitoring wastewater quantity
Cellars are legally obliged to determine the quantity of wastewater on a monthly basis and to keep records for auditing purposes. It is therefore important to use an effective water meter. It is also important to attempt to separate rain water from wastewater in order to limit the volume of contaminated water. At smaller cellars (generating less than 20 ML wastewater per annum) this can ensure that the quantity of wastewater that is contained, qualifies to apply for a registration certificate only, and not for a water license, demanding stricter regulations or requirements.
Wastewater management: monitoring wastewater quality
Prior to disposal, most cellars store and/or pre-treat their wastewater to re-use it or to reduce extreme variations in composition. The following procedure should be used for taking representative wastewater samples:

Sample the wastewater monthly at the point where it is disposed into a catchment dam or onto grass at the depth where it will flow out.
Take a composite sample (instead of a single sample) composed of equal quantities of at least 5 samples taken just before the dam was filled.
Sample at least 1,5L wastewater in a glass container and store below 4°C, or as suggested by the chemical laboratory doing the analysis.
Avoid sampling at times when the inflows are very low, or when rainwater has a diluting effect.
Keep record of cellar activities at the time when sampling takes place, especially when the total volume at the point of collection, is dominated by one or two processes only.
Keep records of all other actions taken.
Cellars are legally obliged to analyse the following chemical parameters at an accredited laboratory:

The electrical conductivity (EC)
pH
Sodium adsorption ratio (SAR)
Chemical oxygen demand (COD)
The chemical composition of wastewater indicates whether the water has potential environmental and/or social impacts when released into nature. Apart from these elements, juice, wine and lees, which are also sources of organic carbon dioxide and inorganic components such as salts, acids and solids, may also end up in the waste stream during the harvest period and contaminate it even further.
Storing of wastewater
If more than 1 000 m3 wastewater is to be stored for disposal purposes on any given day (up to a maximum of 10 000 m3/property or up to 50 000 m3/wastewater dam system) the water user must register with the Department of Water Affairs. If more than 500 m3 is to be stored on any given day for recycling purposes, it should also be registered (maximum of 5 000 m3 will be allowed). If more than 50 m3 wastewater is disposed of in an evaporation pan or wastewater dam system on any given day, it must also be registered (maximum of 1 000 m3 per day will be allowed). The wastewater catchment dams and disposal terrains both have to be situated away from a watercourse, above the 100-year flood line or alternatively further than 100 m from the edge of a water resource or borehole used for drinking water or animal water hole. Any dam (including evaporation pans) with a capacity greater than 50 000 m3 and and with a wall that has a vertical height of more than 5 m, is declared as a dam with a safety risk. Such a dam must be registered with the Department of Water Affairs and various control measures exist for the erection and maintenance of such a dam.
Catchment dams for cellar wastewater are usually designed by engineers. To do this efficiently, the engineer requires information about the volume and composition of wastewater. Cellar management should ensure that the designer at least takes the following into account:

Wastewater must be separated from storm water (rain water).
Pipelines for conducting wastewater must be able to handle the maximum volume at any time and must be made of quality material to prevent leakages.
Catchment dams for wastewater must be able to handle the maximum volume of wastewater at any one time and enough space should be allowed for possible unexpected volumes of wastewater.
Catchment dams should be large enough so that sufficient time may lapse for the solids to be deposited and breaking down of organic matter may take place before the water is released or used for irrigation.
Catchment dams should be situated in such a way that there is no contact with storm water.
Irrigation systems must be designed in such a way that leakages do not occur.
Irrigation of wastewater
Since untreated wastewater of wine cellars does not qualify for disposal in natural water resources, wastewater must either be treated or irrigated. If on any given day a person wants to irrigate more than 10 m3 water originating from the production of wine cellars, he/she must register as a water user and up to 500 m3 per day of this wastewater may be irrigated (for crop production, including grazing), provided that:

The electrical conductivity on any given day is less than 200 milli Siemens per meter (mS/m)
The pH is between 6 and 9
Sodium adsorption ratio (SAR) is less than 5
Chemical oxygen demand (COD) is less than 400 mg/l
If the COD value is higher than 400 mg/l but less than 5 000 mg/l, however, irrigation after registration (without a license) may be up to 50 m3 only on any given day. The registered water user may then only irrigate above the 100 year flood line, or further than 100 m from the edge of a water resource or borehole used for drinking water or animal water-hole, while no groundwater or surface water may be contaminated. The registered user must measure the quantity of water irrigated on a weekly, and the quality on a monthly basis at the point just before irrigation. Written records must be kept for inspection by the responsible authority. The area of irrigation must be demarcated on a 1: 50 000 topographic map and details provided of the crops under irrigation, irrigation techniques and details of emergency procedures. Waterlogging or damaging of soil, occurrence of flies and mosquitoes, bad odours, secondary pollution, penetration of any surface resources and unauthorised use of water by members of the public must be prevented at all times. Solid particles must be removed before irrigation and disposed of efficiently. Storm water (rain water) originating from the irrigation area must be collected to prevent contamination of pure water.
Management of solid waste
Skins, stems, pips and lees must be heaped on an impenetrable layer (such as cement or plastic) and covered against rain, to prevent organic acids from seeping out and having negative effects on soil and soil water before having broken down sufficiently to serve as compost. If no storage space is available, it should rather be used as animal feed. This waste, as well as used sedimentation substances (e.g. diatomatious earth and bentonite clay) and filtration material, must be stored temporarily before being removed to prevent bad odours in the adjacent vicinity. Used filtration material and bentonite should be made available for the recovery of alcohol or tartaric acid where possible to prevent soil and water pollution (which occurs when these substances are exposed to the soil too quickly). From July to December the waste should be taken to a suitable dumping site to be destroyed. Wastewater dams, pipes and other equipment should be cleaned annually and large volumes of sludge are collected in this way. This sludge may only be applied to the soil once the chemical composition thereof has been determined, indicating that it may indeed be applied to a specific piece of land. If the sludge contains high concentrations of certain elements, it may influence the soil, water sources and plant performance. An attempt should be made to conduct the cleaning operation in the summer months to allow rapid breakdown, thus minimising bad odours.
Noise and air pollution
Noise from pumps, compressors, cooling apparatus and vehicles may cause distress to neighbours and gas leakages from refrigeration mechanisms may cause air pollution. For this reason it is required that equipment or vehicle noise exceeding 45 dB outside the cellar be used between 8H00 and 20H00 only. Roads, trucks, tractors, pumps, compressors, refrigeration mechanisms and other equipment causing noise and/or air pollution should be monitored on a continuous basis and regular maintenance records should be kept.
For further details, contact Lourens van Schoor on tel 021-809 3158, or e-mail lourens@nietvoor.agric.za. For more information on the IPW scheme, contact Andries Tromp on tel 021-809 3143, or e-mail andries@nietvoor.agric.za.
Wynboer is incorporated in WineLand, magazine of the SA wine producers.
Subscribe to WineLand

Visit our sister sites:

South African wine farmers' representative organisation

Facts, figures, contact details and much more in the 2009/10 Directory