# Relationship history for MSHA mine 1515772

Current hierarchy: **Horace Garrison  Hill → Red Flame Coal Company → Prep Plant**

- 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:** Nicholas  Saylor et al → Prep Plant; 1978-10-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Bobby Joe  Hensley → Prep Plant; 1982-10-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** New Harlan Block Coal Company Inc → Prep Plant; 1986-10-01 to 1989-09-20; source msha-controller-operator-history
- **controller_controls_operator:** Nicholas  Saylor et al → New Harlan Block Coal Company Inc; 1986-10-01 to 1989-09-20; source msha-controller-operator-history
- **operator_operates_mine:** Day Branch Coal Company Inc → Prep Plant; 1989-09-21 to 1994-06-02; source msha-controller-operator-history
- **controller_controls_operator:** Bobby Joe  Hensley → Day Branch Coal Company Inc; 1989-09-21 to 1994-06-02; source msha-controller-operator-history
- **operator_operates_mine:** Saylor Brothers Enterprises Inc → Prep Plant; 1994-06-03 to 1995-05-15; source msha-controller-operator-history
- **controller_controls_mine:** Nicholas  Saylor et al → Prep Plant; 1994-06-03 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Nicholas  Saylor et al → Saylor Brothers Enterprises Inc; 1994-06-03 to 1995-05-15; source msha-controller-operator-history
- **operator_operates_mine:** D & C Mining Corporation → Prep Plant; 1995-05-16 to 2018-06-18; source msha-controller-operator-history
- **controller_controls_mine:** Horace Garrison  Hill → Prep Plant; 1995-05-16 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Horace Garrison  Hill → D & C Mining Corporation; 1995-05-16 to 2018-06-18; source msha-controller-operator-history
- **operator_operates_mine:** Red Flame Coal Company → Prep Plant; 2018-06-19 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Horace Garrison  Hill → Prep Plant; 2018-06-19 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Horace Garrison  Hill → Red Flame Coal Company; 2018-06-19 to current/open; source msha-controller-operator-history