# Relationship history for MSHA mine 3304023

Current hierarchy: **Miller Robert → Miller Coal & Supply → Burt Strip**

- 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:** Kelly Coal Company → Burt Strip; 1985-08-01 to 1991-07-30; source msha-controller-operator-history
- **controller_controls_mine:** Kelly Glenn O → Burt Strip; 1985-08-01 to 1991-07-30; source msha-controller-operator-history
- **controller_controls_operator:** Kelly Glenn O → Kelly Coal Company; 1985-08-01 to 1991-07-30; source msha-controller-operator-history
- **operator_operates_mine:** Double R Mining → Burt Strip; 1991-07-31 to 1994-12-29; source msha-controller-operator-history
- **controller_controls_mine:** Barker Raymond → Burt Strip; 1991-07-31 to 1994-12-29; source msha-controller-operator-history
- **controller_controls_operator:** Barker Raymond → Double R Mining; 1991-07-31 to 1994-12-29; source msha-controller-operator-history
- **operator_operates_mine:** Miller Coal & Supply → Burt Strip; 1994-12-30 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Miller Robert → Burt Strip; 1994-12-30 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Miller Robert → Miller Coal & Supply; 1994-12-30 to current/open; source msha-controller-operator-history