Related by context. Frequent words. (Click for all words.) 63 mine subsidence 60 subsidence 58 sinkholes 56 Subsidence 55 Sinkholes 51 highwall 51 spalling 50 landslips 50 mold infestation 50 cave ins 49 freeze thaw cycles 49 corroded pipes 49 graben 49 longwall mining 48 sewage backups 48 mines 48 groundwater contamination 48 silica dust 47 Soil erosion 47 sinkhole 47 rockfalls 47 landslip 47 seepage 47 Alluvial 47 mine shafts 47 asbestos contamination 47 sewer backups 47 contaminating groundwater 47 frost heaves 47 earth tremors 47 roadbed 47 roadbeds 46 chimney stacks 46 drainage basins 46 Sinkhole 46 geotechnical engineers 46 drainage 46 mine 46 tailings dams 46 igneous rock 45 tailing ponds 45 hydrothermal activity 45 coal seams 45 adits 45 diggings 45 alluvium 45 soils 45 vapor intrusion 45 dolomite 45 clasts 45 skarn mineralization 44 bridge abutments 44 excavation 44 Soledad Mountain 44 Seepage 44 naturally occurring asbestos 44 drainage pipes 44 subsurface 44 timbering 44 Asbestos removal 44 surficial 44 Dewatering 44 sewerage pipes 44 Dunkard Creek 44 sanitary sewer overflows 44 Hobet 44 mine tailings 44 depositional 43 sulphide bearing 43 structural defects 43 compacted soil 43 seismicity 43 coal mines 43 rockfall 43 trench 43 floodings 43 flooding 43 MSHA inspectors 43 polluted groundwater 43 alluvial mining 43 topsoil 43 sewer mains 43 tailings impoundment 43 coal mining 43 culverts 43 quarries 43 borings 43 trenched 43 tailings dam 43 termite infestation 42 breccia pipe 42 massive sulphide deposits 42 earthen dams 42 valley fills 42 Trenching 42 sewer pipes 42 alluvial deposits 42 opencast mining 42 glacial till 42 sumps 42 rockslides