Hard rock aggregate inventories at the Geological Survey of Finland (GTK)—their use in land-use planning and aggregate accounting

Inventories of bedrock outcrops suitable for aggregate production have been carried out at the Geological Survey of Finland since 1989 and now include over 12,000 outcrops. Initially, the aim of the inventories was to locate outcrops for high quality aggregate production but the work has developed with regional co-operative POSKI projects seeking to reach a balance between groundwater protection and aggregate supply. Based on evaluation in the field and mechanical–physical tests, about 1% of the bedrock outcrops studied meet the highest quality requirements. As an example of the societal implication of the inventories, 44 areas with regionally significant aggregate reserves were identified in the 1st Complementary Stage of the Uusimaa Regional Land Use Plan, in order to secure the supply of aggregates with good quality. In 2008, GTK opened a web based aggregate accounting service to provide information on available reserves in high demand regions in Finland.