Human waste has the potential to affect wilderness and aesthetic values, to introduce diseases into wildlife and to alter ecosystem balances by raising nutrient levels.
We've been treating sewage at Australia’s Antarctic stations since their establishment. In early years human urine was tipped into the sea while solid waste was burnt using wood, briquettes or gas, or treated with caustic soda. These stations now have flush toilets and secondary sewage treatment plants. There is concern that effluent from the plants, which is released into the sea, may contain organisms capable of infecting wildlife; sterilisation of this effluent is now being trialled. Sludge from the treatment plants, formerly disposed of on the sea ice, is now returned to Australia.
We return human waste from Antarctic field sites wherever possible, as required under the Madrid Protocol and Australia’s Environmental code of conduct for Australian field activities in Antarctica. Solid human waste is collected in plastic bags and returned to the station for incineration. Urine is collected in drums and disposed of in stations’ sewage systems, although direct disposal in tide cracks is allowed at coastal sites. Facilities in the field range from purpose-built structures or adaptations — such as the toilet at Jack’s donga made from an old bulldozer cabin — to drums in the open; but they all have one feature in common — spectacular views.
Under the Madrid Protocol waste produced at inland camps may be disposed of in ice pits, provided certain conditions are met, and after consideration of the potential environmental impacts of disposal on site compared with alternatives. Considerations include the impacts of providing and burning gas if gas toilets are used, of transporting and treating waste on stations or transporting and shipping it to Australia. These issues are now being considered in planning for a major research program in the southern Prince Charles Mountains next summer.
Sewage on subantarctic Macquarie Island is only macerated before being released into the sea. This is considered an acceptable practice because of the rapid mixing and dilution which occurs in the surrounding ocean. At coastal sites away from the station, waste can be disposed of directly into the ocean. However, faeces must be removed from all inland sites for disposal in the ocean, to protect alpine vegetation on the central plateau.
Elizabeth Kerry, Operations Environment Officer, AAD