# Relationship history for MSHA mine 3607331

Current hierarchy: **Thomas William D → Tailings Process Corp → Nemacolin Mine**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-13T11:19:05.459773+00:00

## Valid-time edges

- **operator_operates_mine:** Tailings Process Corp → Nemacolin Mine; 1982-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Thomas William D → Nemacolin Mine; 1982-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Thomas William D → Tailings Process Corp; 1982-06-01 to current/open; source msha-controller-operator-history