# Relationship history for MSHA mine 4605320

Current hierarchy: **Occidental Petroleum Corp → Island Creek Coal Company → Alpine Mine**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **controller_controls_mine:** Occidental Petroleum Corp → Alpine Mine; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Massey Energy Company → Alpine Mine; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Robinson-Phillips Coal Company Inc → Alpine Mine; 1976-09-20 to 1986-05-11; source msha-controller-operator-history
- **controller_controls_operator:** Massey Energy Company → Robinson-Phillips Coal Company Inc; 1976-09-20 to 1986-05-11; source msha-controller-operator-history
- **operator_operates_mine:** Black Horse Coal Mining & Sales Inc → Alpine Mine; 1986-05-12 to 1989-01-22; source msha-controller-operator-history
- **controller_controls_mine:** Thomas Lewis C → Alpine Mine; 1986-05-12 to 1989-01-22; source msha-controller-operator-history
- **controller_controls_operator:** Thomas Lewis C → Black Horse Coal Mining & Sales Inc; 1986-05-12 to 1989-01-22; source msha-controller-operator-history
- **operator_operates_mine:** Robinson-Phillips Coal Company Inc → Alpine Mine; 1989-01-23 to 1989-12-05; source msha-controller-operator-history
- **controller_controls_operator:** Massey Energy Company → Robinson-Phillips Coal Company Inc; 1989-01-23 to 1989-12-05; source msha-controller-operator-history
- **operator_operates_mine:** Island Creek Coal Company → Alpine Mine; 1989-12-06 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Occidental Petroleum Corp → Island Creek Coal Company; 1989-12-06 to current/open; source msha-controller-operator-history