# Relationship history for MSHA mine 3608315

Current hierarchy: **Lucas Gary → Aka Coal Company → Dundas Tunnel**

- 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

- **controller_controls_mine:** Lucas Gary Et Al → Dundas Tunnel; 1989-03-27 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Aka Coal Company → Dundas Tunnel; 1992-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Lucas Gary Et Al → Aka Coal Company; 1992-01-01 to current/open; source msha-controller-operator-history