Researchers from The University of Queensland have found that as much as 80% of the Pacific region’s sand and aggregate (used to build houses, roads, bridges, and to protect coastlines from the impacts of climate change) come from Fiji – at great cost for some of Fiji’s rivers.
Dr Paul Rogers, Senior Research Fellow at the Global Centre for Mineral Security, and lead author of a new study, explained that the Pacific Island countries are looking for support to diversify their access to minerals, which could create new economic opportunities across the region.
Unlocking new economic opportunities
“Many Pacific countries are built on rock made of calcite, a mineral unsuitable for some building applications,” he said, and added that mineral security has emerged as a pressing concern for the region: countries are forced to import, at high cost, large volumes of the materials necessary for their development, so alternatives are needed.
“There is an amazing opportunity for Fiji and other Pacific Islands to reduce pressures on rivers, beaches and reefs by exploring alternative sources of aggregates,” Dr Rogers said, adding that the Asian Development Bank has estimated over $30 billion needs to be invested in Pacific Island countries infrastructure by 2030.
Dr Rogers and his co-authors found that Nauru’s 30 million cubic metres of limestone dolomite (a legacy of phosphate mining) can be crushed to produce high-quality aggregate suitable for concrete and other applications.
New Caledonia also has 25 million tonnes of ferro-nickel slag that can be used as an aggregate or supplementary material in cement.
A longer-term option for these countries might be to produce ore-sand by-products from silicate rich metal ores for both domestic and export markets.
The importance of diversifying supply
Robert Smith, a Fiji-based geophysicist and a co-author of the report, explained that because of aggregate extraction, Fiji’s Navua River has seen its gravel bar area decrease at an alarming rate in recent decades.
“We need to be looking for sustainable, alternative sources. Even in the atoll countries such as Tuvalu, experience shows that sand aggregates can be harvested from lagoons at a sustainable rate, providing careful marine environment studies are undertaken,” he said.
The study, the most comprehensive snapshot ever compiled of aggregates supply in the region, was conducted in partnership with the Pacific Community and Smith Geoscience Consulting on behalf of the Pacific Regional Infrastructure Facility.
