Portland and Bath Stone Quarries
The Isle of Portland’s industrial legacy results in ubiquitous old quarries, landfills and coastal instability. Inevitably the upmarket transformation involves complex special foundations, appropriate soils: gas measurements and remediation of contamination. Most Bath Stone quarries are hidden, having been backfilled, but careful study of old maps reveals their former locations. Trial trenching and liberal scatter of rotary-percussive probes define their depth, and backfill. Organic or contaminated waste is relatively rare. If ‘gulled’, fractured bedrock is anticipated, rafts supported by vibro stone columns may be preferred to piles alone.