Solid Energy’s has achieved a major milestone with high-quality humates from its New Vale mine in Southland – gaining organic certification with BioGro New Zealand, the country’s leading organic certification agency. Scientific testing recently confirmed that select lignite seams at New Vale are a source of high-quality humates, which could play a key role in greening New Zealand both literally and figuratively. “Humates are rich in humic and fulvic acids and these acids help retain nutrients for plants,” says Solid Energy Environmental Business Manager, Dr Paul Weber. Early results show that the humate product from New Vale could have more than 30% humic acid. “Our last load, which we shipped recently, had a humic acid content of 43%, which was fantastic.“Exploratory laboratory trials have indicated humates can slow the leaching of nitrogen fertilisers,” he says. “This may allow plants to use more of the nutrient before it leaches away. By helping soils retain nitrogen, humates could offer financial benefits to farmers and also reduce the negative effects of leaching on aquifers and rivers.” Weber says New Zealand farmers and gardeners apply about 2,000 t/y of humates but the market is predicted to jump to 10,000 t in the coming years due to its increasing reputation. “Most of the humates used in New Zealand are currently imported from Australia, involving considerable transport costs, so we hope that our New Vale discovery can provide a comparable high-quality local source,” he says.Solid Energy has an agreement with New Zealand Humates Ltd (NZH) to supply humates for the New Zealand market. Dave Whitteker, Managing Director of NZH and an eight-year advocate of humates, says the supply deal represents an opportunity to harness New Zealand’s own natural resources in a very green way and reduce the country’s reliance on international imports. “Now that we’ve gained organic certification of the New Vale mine humates with BioGro New Zealand – the local product is even more palatable for customers,” Whitteker says. A number of his clients now use 4 to 10% humate mixed with fertiliser and agricultural limestone applications to maximise pasture and crop response.“Further research is required on this product, under New Zealand conditions, to maximise the benefits, and trials are currently under way with Lincoln University,” Whitteker says. Weber, who also manages environmental research and development for Solid Energy, concludes that the humate market is young but has strong potential. “We are already investigating options for liquid humates that could be used for blended fertilisers, water treatment and clean-up of contaminated sites. Watch this space,” he says.