Construction activities including piling, excavation, fuel storage, and concrete washout can contaminate groundwater. Groundwater feeds drinking water supplies, rivers, and wetlands. A pollution incident can result in prosecution, costly remediation, and lasting environmental damage. Preventing groundwater contamination is a legal obligation for every construction site. This talk covers the controls needed to protect groundwater during construction.
Key Hazards
Fuel or oil spills migrating through permeable ground to the water table
Concrete washout entering groundwater through unlined settlement areas
Piling operations creating pathways for surface contaminants to reach aquifers
Contaminated runoff from stockpiles infiltrating through exposed ground surfaces
Control Measures
Store all fuels, oils, and chemicals in bunded areas on impermeable surfaces.
Conduct concrete washout only in designated, lined containment areas with no drainage outlet.
Use bentonite or grout seals on piling operations where the risk assessment identifies aquifer risk.
Install cut-off drainage and impermeable barriers around areas of known ground contamination.
Complete a hydrogeological risk assessment before any excavation below the water table.
Monitor groundwater levels and quality at designated boreholes throughout the construction period.
Report any spill or suspected contamination to the environmental manager immediately.
Obtain an environmental permit from the Environment Agency for any discharge to groundwater.
Brief all operatives on the groundwater protection measures specific to this site.
Remember
Store all fuels, oils, and chemicals in bunded areas on impermeable surfaces only
Carry out concrete washout only in designated lined containment areas with no outlet
Report any spill or suspected contamination to the environmental manager immediately
Monitor groundwater at designated boreholes throughout the construction period
An environmental permit is required for any discharge to or near groundwater