# Relationship history for MSHA mine 1511521

Current hierarchy: **Massey Energy Company → Wolf Creek Collieries Company Inc → Kentucky Border Tipple**

- 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:** Massey Energy Company → Kentucky Border Tipple; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Gold Star Coal Company → Kentucky Border Tipple; 1978-08-01 to 1979-06-30; source msha-controller-operator-history
- **controller_controls_mine:** Mc Nally C J & Ken L Hall → Kentucky Border Tipple; 1978-08-01 to 1979-06-30; source msha-controller-operator-history
- **controller_controls_operator:** Mc Nally C J & Ken L Hall → Gold Star Coal Company; 1978-08-01 to 1979-06-30; source msha-controller-operator-history
- **operator_operates_mine:** Wolf Creek Collieries Company Inc → Kentucky Border Tipple; 1979-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Massey Energy Company → Wolf Creek Collieries Company Inc; 1979-07-01 to current/open; source msha-controller-operator-history