The disposal of slurry and waste concrete poses a potential environmental risk if not managed properly. Creating and maintaining a designated wash-down area allows contractors to wash equipment correctly while reducing the risk of pollution to land or water.
Managing Concrete Washout
Concrete wash water is alkaline (pH ~12) and contains high levels of Chromium, which can harm land, seep into the ground, and contaminate groundwater. Poorly managed concrete washout can also increase the pH of surrounding waters and pose a risk to aquatic life.
Effective washout facilities:
• Contain liquids and slurry from concrete mixers and pump hoppers
• Combine solids for simpler reuse or disposal
• Prevent contaminated runoff that can clog drains and cause flooding
• Promote “good housekeeping” on construction sites
Location and Management of Washout Areas
To reduce environmental risks, consider these measures:
• Place the washout area away from stormwater drains, drainage lines, and water bodies
• Ensure the area is convenient and clearly indicated
• Contain all wash-down water within a watertight bund
• Do not use washout areas to store excess concrete; return it to batching plants or designated on-site receptacles
• Scrape excess concrete from equipment before washing to reduce water use
• Use a high-pressure, low-volume spray nozzle to conserve water
Monitoring
Washout areas should be maintained and monitored to ensure functionality and storage capacity. Monitoring should occur:
• Weekly during dry weather
• Before forecast rainfall
• During rainfall events
• As soon as possible after rainfall
Set concrete should be removed to reinstate capacity and prevent overflows.
Environmental Incidents
Any environmental incidents must be reported immediately. An incident occurs if concrete is washed outside the designated area.
If you want to talk to the experts in concrete washout, contact a PumperDump specialist at info@pumperdump.com.au or via the PumperDump App (App Store / Google Play).
Ref: Extracted from the NSW Government’s Concrete Washout Guidelines
