PRELIMINARY HAZARD MAPS OF SUBSIDENCE NEAR GOLD HILL, NC

The Gold Hill District of North Carolina has been a place of historical significance from Gold Hill’s first discovery of proven gold veins in 1824. Since then extensive mining operations continued until operations were ceased in 1915. In the past decade the remains of the Gold Hill mining district has left many existing surface hazards, as well as the potential for future hazards relating to concentrated subsidence from filled mine shafts and stopped areas. The primary concern for the local community of Gold Hill is to know the magnitude of the hazards and to understand where potential hazards are located. To identify potential hazards we have completed some exploratory Ground Penetrating Radar (GPR) surveys that allows us to map the concentrated subsidence at various locations throughout the Gold Hill mining district. The GPR is being used to create both two dimensional and three dimensional transects of the surface. Using various frequencies for different depths, it is possible to see that disturbances in the sediment exist, but the data only shows features to depths as shallow as five to ten meters. These shallow disturbances are of primary interest but could also point to larger scale issues. The application of the GPR technology allow for a better understanding of the past mining network that once flourished in the region and the hazard associated with the subsidence of the material within these old shafts.