Analysis | The gift of waste

Corporate Social Responsibility and sustainability walk hand in hand. CSR purposefully integrates a company into its corporate eco-system and does not impose costs (externalities) on the community, the environment and other stakeholders. In Macau, the dumping of operational by-products (resource-rich waste, such as food waste) into the South China Sea cannot be seen as a sustainable activity and is antithesis to CSR.
Natural systems have an incredible ability to absorb and process outputs; in nature there is no waste. The leftovers from one organism become resources for another in a circular system, emulated by models of the Circular Economy. There is, however, a limit to the volume beyond which any system becomes overburdened. What was once a gift to an organism or ecosystem, in the wrong place or volume, becomes toxic. No longer usable, it becomes waste. One role of CSR is to identify and attend to those externalities.
As has recently come to public attention, Macau’s waste-management systems have become over-burdened: the consistently high per capita production of solid waste at 2.17 kgs per day (2018 figures); the decision not to plant mangroves along the northern part of the Areia Preta coastal area, and to reclaim the area instead to deal with the stench; and burden-shifting from one waste-stream to another all corroborate that story.
The reversal of the decision to plant mangroves deserves exploration. Mangroves’ adaptability to low levels of oxygen, mud, salt and pollutants, and their stabilizing effects against coastal erosion and movement of silt, particularly in locations prone to typhoons, makes them eminently suited to such applications as recommended by the Environmental Protection Bureau. Even though these plants have phenomenal capacity to absorb gases and uptake nutrients from anaerobic environments, Macau’s coastal zones have become unviably polluted with what experts describe as ‘very nasty toxic stuff that kills fish and can kill people’: a concoction of liquid with suspended solids, oils and fats, and toxicity that kills any natural bacteria that would normally start the process of biodegradation. Macau’s lack of capacity to sufficiently treat its wastewater has led to under-treated effluent and sludge being discharged into surrounding waters.
Adding to the problems is Macau’s comparatively high solid waste volume. This can be better managed by reducing food waste – the heaviest fraction of general waste. Food waste also causes damage to the Energy from Waste (EfW) infrastructure – incinerators and transportation network – as it contaminates general waste with its corrosive and moist characteristics. Given Macau’s branding as a city of abundance, luxury and gastronomy, the capacity to reduce food waste from hotels and resorts is limited. Management, thus, naturally focuses down-stream, and the current option of choice is the already over-burdened sewerage system: a classic burden-shifting scenario.
Some of the food waste management systems currently in use in Macau may produce “earth-friendly water” in another context, but a system that wastes 2 to 4 litres of potable water per kilogram of food waste in bacteria-activated macerators to push more solids down the sewer creates clear externalized costs under Macau’s particular circumstances – an already over-burdened public infrastructure that puts even greater pressure on an already degraded marine environment. Under U.K. legislation, the output of such systems is very highly regulated, if not banned.
Food waste can, however, offer other gifts: composted for fertilizer, soil additives and animal feed; biogas from anaerobic digesters and anaerobic co-digesting systems.
Of these, Macau does not have the space to store and produce compost, and some Integrated Resorts that have tested this option have had export to the mainland cut off. Lack of agriculture means soil additives and animal feeds are not viable options. Anaerobic digesters and co-digesting options producing biofuels, although recommended for use in Macau for its health, environmental and energy capture benefits in a 2016 study by Hong Kong researchers, would require significant investment in upgrades to wastewater treatment infrastructure.
In the absence of anaerobic digesters, the ideal scenario, allowing for Macau’s existing infrastructure, is the production of odorless, high calorific, low weight, low volume and dry fuel for EfW. Waste management systems are currently available which can be incorporated into community waste-collection points, and hotel and restaurant in-house food-waste management to efficiently produce such a residue: volume (therefore transport requirements) is reduced by 80%, without using water, moderate energy use, with no off-gas, no pathogens, nor pest risk. The subsequent reduction in the burden on the public waste-water treatment infrastructure and our marine environment, and decontamination of the Municipal Solid Waste suggests the way forward is public-private partnerships with Integrated Resorts to consider such options.
The socially responsible action of corporates is to audit the impacts of operations both within and out the back door, beyond companies’ physical boundaries, and then to offer solutions in collaboration with other stakeholders.
In the lull before economic activity ramps up post Covid-19, and before the existing waste-management infrastructure starts to creak again under the burden, with good will, there is a window of opportunity to make Macau an exemplar and turn such waste into a gift.