The pace of housing development over the past few years meant that brownfield issues had to be addressed quickly when a development is started. By Frank Westcott
Speed was more important than cost: removal and disposal of Japanese Knotweed infested soil, for example, won out over simple herbicide treatment that can take two or three years to complete.
In more difficult times, big ticket activities such as site investigation and remediation will inevitably be seen as expenditures that can be put off until market conditions approve. However the old adage “A stitch in time saves nine” still applies – and many low-cost actions can provide significant time and cost benefits for the future development of the site.
Some examples are:
- Ensuring vehicular access to sites, and therefore fly-tipping, is prevented. Cost – hundreds of pounds; savings - thousands of pounds in clearance and disposal costs.
- Herbicide treatment to eradicate invasive plants (Japanese Knotweed). Cost – hundreds to low thousands of pounds but may require two to three annual treatments; savings – tens of thousands of pounds for excavation and disposal of rhizome-infested soil;
- Completing ecological surveys. Costs – low thousands of pounds; savings – months or even years of delay saved by allowing mitigation works to be pre-planned;
- Manage vegetation growth and prevent formation of ponding water on site. Cost – hundreds of pounds; savings – tens of thousands of pounds if colonisation by protected species such as Great Crested Newts is avoided. But note that if protected species are already there, damaging their habitat is illegal.
- Remediation strategy. Even if remediation itself is to be deferred, complete the remediation strategy and regulatory approvals stage. Cost - a few thousand pounds; saving – months of time when the development goes ahead.
- Long term, low cost remediation techniques: methods such as Monitored Natural Attenuation can be carried out during the period of deferment of the project, potentially avoiding the need for later large scale excavation-based intervention altogether. Cost - low thousands of pounds; savings – tens or hundreds of thousands of pounds.
Frank Westcott is associate director with RSK