The potential of social dialogue on biosolids research and policy in New Zealand

Approximately one million tonnes of sewage sludge (biosolids) are produced annually throughout New Zealand. Currently most of the biosolids are disposed of daily in landfills. Strategies for ‘beneficial use’ are currently focused primarily on land application of biosolids. The long-term success of these and other strategies is dependent on their environmental, economic, social and cultural sustainability. New Zealand can learn from varied international land application approaches and experiences. Following decades of land application of biosolids, Germany, Denmark and Switzerland are considering banning land application in light of uncertainties around the impacts of some of the compounds contained in biosolids. In the United States the application of biosolids to agricultural and forestry land has been occurring for several decades; however, public opposition to land application of biosolids has significantly increased in the United States since the mid-1990s. This opposition has voiced a range of concerns, including trace metals, pathogens, odours, surface water and groundwater quality, soil and food/crop quality, monitoring effectiveness, enforcement, transportation, economic viability, pharmaceuticals, and the ‘uncertainty and unknowable-ness of exactly what is in a particular biosolids product’.We argue that the biosolids industry and responsible local authorities in New Zealand need to involve the community in decision-making around the use or disposal of biosolids. This interaction should be neither a public relations exercise nor a one-way education service. Community dialogue, using methods such as scenario workshops, would potentially enable authorities and experts to understand community concerns and to recognise the value choices that underlie ‘technical’ decisions, as well as the limitations of their technical knowledge. Community participants would be enabled to “own” the problem of waste generation. Such a dialogue could determine acceptable solutions that take into account both technical and community advantages and disadvantages of alternative outcomes. At their best, community dialogue methods such as scenario workshops can produce outcomes that acknowledge areas of uncertainty, identify research gaps, suggest potential improvements in current practice, and take into account community concerns when setting priorities.