Across the world, sand and gravel are being extracted faster than they can be replaced, according to a new report published in the journal Nature:
Most of the trade in sand is undocumented.... Illegal sand mining is rife in around 70 countries, and hundreds of people have reportedly been killed in battles over sand in the past decade in countries including India and Kenya, among them local citizens, police officers and government officials.
A group of scientists has now called for a global monitoring programme for sand resources – "A Global Agenda For Sand":
In order to move towards globally sustainable sand extraction, we need to fully understand the occurrence of sustainable sources, and reduce current extraction rates and sand needs, by recycling concrete and developing alternative to sand (such as crushed rocks or plastic waste materials). This will rely on a knowledge of the location and extent of sand mining, as well as the natural variations in sand flux in the world’s rivers. A global sand monitoring program is thus imperative.The researchers say there are seven components essential for sustainable sand extraction: Source. Replace. Reuse. Reduce. Govern. Educate. Monitor.
At least three of those components are as applicable in the UK as they are elsewhere:
Replace. Local and national governments and planning authorities should encourage greater use of alternatives to sand, such as crushed rock, industrial slag and waste (including copper, fly ash and foundry sand) and recycled plastic. For example, roads, car parks and driveways made from plastic waste embedded in asphalt can lessen demand for bitumen and aggregate.
Reuse. Sand-based materials should be reused when possible. For example, demolition waste and concrete can be crushed and mixed into cement. Rubble can be used as a base aggregate for building foundations and roads, for filling holes and as gravel for walkways, gardens, noise barriers and embankments. Legislation and controls on the disposal of concrete, and financial incentives to reuse old concrete, will be needed.
Reduce. Cutting the amount of concrete required in new structures would also lessen the demand for sand. This could be achieved by using more efficient materials (such as concrete blocks and printed construction panels with hollow cores). Industry standards for material qualities will be needed and should be backed up by regulations to enforce usage.
Comment: Sand and gravel are being removed faster than they can be replenished. Sand mining, both legal and illegal, needs to be monitored and managed globally. https://t.co/GgpKZjjMgq— nature (@nature) July 3, 2019
