DSTP is banned in Australia and in China but conventional tailings dams can also host environmental challenges, especially in Pacific Ring of Fire nations, which are susceptible to high rainfall and the odd earthquake event.
With an outcome due on Wednesday, a result favourable to the Ramu NiCo project could trigger some unrest from landowner groups near Basamuk Bay.
A shortage of land on Lihir Island is one of the main reasons DSTP is used at the major Lihir gold mine in PNG.
Former Lihir Gold chairman Ross Garnaut blasted an Australian television report on DSTP at the mine last year, telling The Australian DSTP only caused some impacts on plankton and had no adverse impact further up the food chain.
Both the CSIRO and the PNG Department of Environment and Conservation have monitored the DSTP impacts from this mine and have long-term data.
The $US1.5 billion Ramu NiCo project has been subject to various delays, with production initially expected to start in 2009.
Work on the project was suspended last week due to safety concerns and there has previously been unrest between the PNG and Chinese workers at the site, with a Chinese worker killed in early 2010.
Ramu is expected to produce 31,150 tonnes of nickel and 3300t of cobalt per annum in a high-grade concentrate over a 20-year mine life, but resources have the potential to increase this by a further 15-20 years.
China Metallurgical Construction Company subsidiary MCC Ramu NiCo owns 85% of the project while Australia-listed Highlands Pacific owns 8.56%.
PNG's Mineral Resources Ramu owns 3.94% of the Ramu project and landowner company Mineral Resources Madang owns the remaining 2.5%.