Soil: Construction, Planning and Extraction

The sealing of soils can result in reduced biodiversity, increased flooding of built areas and loss of productivity. Ireland has a sealed surface of 292 m2 per person, much higher than the EU average owing to the extremely dense road network for a very sparsely populated country. To minimise soil sealing, identifying previously developed sites or brownfield sites, for development is increasingly being used. Risk assessment, environmental assessment, detailed risk management and mitigation strategies applied during construction followed by a post-construction monitoring phase are necessary for these developments due to potential contamination issues associated with historical uses. In an Environmental Impact Statements, construction projects must include a list of alternative uses for the receiving environment. One potential value is the agricultural value of the soil. Increasingly, urban agriculture is being recognised in urban planning which is viewed as having a role beyond food production. Flooding events are common in Ireland, and although implementation has been slow, sustainable urban drainage systems (SuDS) are being promoted in Ireland since 2005. Soil in the urban environment also link green areas together and can support the maintenance of biodiversity. Some construction projects require soil to be stored for reuse to protect the genetic seedbank of the site prior to construction. The emergence of green infrastructure and the concept of urban metabolism are also described in this chapter. Finally, the impacts of extraction, including mining, on soils are described.