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| delaminated rock strata (1) |
| displacement (1) |
| goaf stowing (1) |
| haulage gate (1) |
| pillar (1) |
| protective facilities (1) |
| delaminated rock strata (1) |
| displacement (1) |
| goaf stowing (1) |
| haulage gate (1) |
| pillar (1) |
| protective facilities (1) |