While there are some similarities with processing other materials used in the textile, apparel and footwear industry, the processing of leather requires the use of some different chemicals. ZDHC will therefore work with the leather industry to create a leather-specific version of these guidelines.
The processes and chemicals used for the production of raw materials (e.g. polyester) varies widely, depending on the raw material type. The intention with the ZDHC Wastewater Guidelines was to focus on parts of the value chain with the most immediate need for improvement.
ZDHC acknowledges that processes in the textile, apparel and footwear industries can differ and that it is therefore more difficult to meet the limit values for some types of production. Nevertheless, ZDHC believes that with the following in place, all processes in scope of the guidelines can meet the limit values: effective personnel training, implementation of good operations and maintenance practices, and the proper use of commercially-available technology. The limit values will be reviewed periodically to ensure practical implementation is feasible, but also with the clear aim of protecting the environment and human health.
Sludge is a by-product of many types of wastewater treatment systems and therefore an important parameter to sample and test. Almost all facilities generating sludge are currently required by law or permit to sample and test the sludge to determine if it classifies as hazardous or non-hazardous prior to disposal. By including sludge in the scope of the guidelines, ZDHC can help to ensure zero discharge of hazardous chemicals from the key pathways of wastewater treatment systems.