Types of use: concrete, cement, mortar, plaster, as a bedding material, asphalt
Environmental Impacts:
Extraction
Erosion of channel bed and banks, increase in channel slope, and change
in channel morphology. These impacts may cause:
- the undercutting and collapse of river banks
- the loss of adjacent land and/or structures
- upstream erosion
- downstream erosion
- downstream changes in patterns of deposition
- destruction of riverine habitats
Transport
Transport using large trucks affects rural roads and may cause noise and
air pollution.
Production/Treatment
None
Toxicity
None
Environmental Benefits:
None
Potential Material Alternatives:
Manufactured sand (crushed rock / gravel), sea sand, crushed rubble (debris), fly ash/bottom ash, recycled building and quarry dust
Environmental Better Practices:
Design and Planning
- Use alternatives to concrete / mortar: e.g. stabilized earth walls
(Refer to Wall Materials section) - Use premixed concrete instead of in-situ mixing
- Use prefabricated concrete items
- Optimum concrete mix design
(don’t over specify) (BRE mix Design, ACI method of concrete
mix design) - Use standard bricks to minimize mortar and plaster
Storage
- Should be stored in a manner free from contamination by other site materials, for example, by providing containment with proper base and kerb.
- Should be protected from rain and other water sources.
Use
- Adhere to the building specifications mixing mortar and concrete and
building. Overuse of material will not add any additional strength and will
only cause waste. - Mix in small adequate batches to minimize waste. Don’t mix up more fresh concrete/mortar than you will use in a two-hour period.
Disposal
Never dispose wash out cement, sand, cement mortar or concrete into
environment. They can be:
- reused onsite/offsite for construction purposes (e.g. filling)
- safely transported to a construction material recycling facility, or
- safely transported to a sanitary landfill
Key Resources for River Sand:
Environmental, Health, and Safety Guidelines for Construction Materials Extraction – International Finance Corporation (IFC)
Sand, Rarer than One Thinks – Global Environmental Alert Service, UNEP
Construction Site Best Management Practice (BMP) – California Department of Transport
Standards for Material Handling, Storage and Disposal – US Bureau of Reclamation
Recycled Aggregates – Portland Cement Association (PCA)
Guidelines for Selective Demolition and On Site Sorting – Civil Engineering and Development Department (Hong Kong)