# Relationship history for MSHA mine 1507451

Current hierarchy: **Central Kentucky Landscaping Company → L T Ruth Coal Company Inc → Floyd No 1 Surface**

- 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:** B W H Coal Inc → Floyd No 1 Surface; 1974-10-18 to 1977-08-14; source msha-controller-operator-history
- **controller_controls_mine:** Bizzack John → Floyd No 1 Surface; 1974-10-18 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Bizzack John → B W H Coal Inc; 1974-10-18 to 1977-08-14; source msha-controller-operator-history
- **controller_controls_mine:** Central Kentucky Landscaping Company → Floyd No 1 Surface; 1976-04-27 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** L T Ruth Coal Company Inc → Floyd No 1 Surface; 1977-08-15 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Central Kentucky Landscaping Company → L T Ruth Coal Company Inc; 1977-08-15 to current/open; source msha-controller-operator-history