New Zealand biosolids : lost opportunity or just lost?

Of the thousands of tonnes of sludge produced annually in NZ wastewater treatment plants over 60% is disposed of in landfills or long term on-site storage, which is seen as a low cost, low risk solution by regulators and biosolids producers. This is a cost to the community, gives no environmental benefit and conflicts with government policy. Uncertainty still exists with regulator, iwi and communities regarding how much of any contaminant to allow on land, and many stakeholders feel their concerns are not adequately reflected in the current NZ Guidelines. This paper provides a history of events related to biosolids regulatory control and its impact within the country. It includes an estimate of the amount and potential value of biosolids in New Zealand and provides a comparison with usage in other countries, thus indicating our ranking relative to our trading partners. This clearly illustrates why an update is an imperative.