Coastway Surveys was commissioned by Tarmac plc to undertake a sub-surface survey following the discovery of a 1.5m diameter hole in the new quarry floor during the removal of blast material. Initial surveys by Tarmac plumbed the hole to a depth of 25m. Coastway Surveys deployed the sonar unit, configured specifically for lowering into submerged underground cavities, to acquire horizontal profiles up to 200m range.

The survey data were geo-referenced on site using GPS and total station. These data were used to generate a plan, sections and a 3D model cavity beneath the blast area.

The resultant data set provided a volume calculation in true space which allowed the client to determine the 3D extent of the Karst cavity system and was incorporated into the quarry design model for future operations.

Skipton Quarry, UK

Services:Sub-surface Surveying
Project Value:£500,000
Components:Sonar
GPS
Deliverable:CAD Drawings
Volumes & Sections