"Mini-Superfund" Site in Kawerau, New Zealand: A Closer Look at Water Quality

Abstract

In 1954 New Zealand's government passed the Tasman Pulp and Paper Enabling Act, which gave the Tasman company carte blanche to do everything necessary to create the Pulp and Paper Mill's waste disposal site on Maori Trust land. Consequently, the former Lake Rotooitipaku has become Tasman Pulp and Paper’s primary disposal site. This area has been described as "one of the worst locations one could contrive for a waste disposal site" and previous site assessments have identified groundwater and soil contamination at levels that exceed national and international guidelines for drinking water, agricultural use, and ecological health and protection. An unmet need to fully characterize surface water contamination in the principle surface water bodies neighboring the former Lake Rotooitipaku has shaped the objectives of this Masters Project. One primary objective of this project is to investigate the nature and extent of the inorganic contamination in principle water bodies neighboring Lake Rotooitipaku. Additionally, this project uses chemical and isotopic fingerprinting to distinguish between geothermal and anthropogenic sources of contamination. This project is based on systematic fieldwork and sampling of several key water sources in the area. None of the inorganic constituents measured in A8 pond, Urupa pond, or Tarawera River exceed the ANZECC guideline values for recreational water use. Therefore we conclude that the water quality is acceptable, with regard to inorganic contamination, for recreational purposes. Hydrogen and oxygen isotopic fingerprints and conservative mixing calculations suggest that geothermal waters have mixed only with the Tarawera River, but not with A8 and Urupa ponds. Furthermore, the evidence suggests that there is no source of inorganic anthropogenic contamination in the principle surface water bodies. Further research is necessary to explore potential sources of organic contaminants in A8 pond, Urupa pond, and the Tarawera River.