# Relationship history for MSHA mine 1504020

Current hierarchy: **Alpha Natural Resources, Inc. → Peter Cave Mining Co. → Mine #1**

- 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:** Wolf Creek Collieries Company Inc → Mine #1; 1950-01-01 to 1987-07-09; source msha-controller-operator-history
- **controller_controls_mine:** Massey Energy Company → Mine #1; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Massey Energy Company → Wolf Creek Collieries Company Inc; 1950-01-01 to 1987-07-09; source msha-controller-operator-history
- **controller_controls_mine:** Massey Energy Company → Mine #1; 1980-08-01 to 2011-05-31; source msha-controller-operator-history
- **operator_operates_mine:** Wolf Creek Collieries Company → Mine #1; 1987-07-10 to 1992-11-23; source msha-controller-operator-history
- **controller_controls_mine:** Shell Oil Company → Mine #1; 1987-07-10 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Shell Oil Company → Wolf Creek Collieries Company; 1987-07-10 to 1992-11-23; source msha-controller-operator-history
- **operator_operates_mine:** Wolf Creek Collieries Company → Mine #1; 1992-11-24 to 1998-09-01; source msha-controller-operator-history
- **controller_controls_mine:** Zeigler Coal Holding Company → Mine #1; 1992-11-24 to 1998-09-01; source msha-controller-operator-history
- **controller_controls_operator:** Zeigler Coal Holding Company → Wolf Creek Collieries Company; 1992-11-24 to 1998-09-01; source msha-controller-operator-history
- **operator_operates_mine:** Wolf Creek Collieries Company → Mine #1; 1998-09-02 to 2000-01-19; source msha-controller-operator-history
- **controller_controls_mine:** Horizon Natural Resources Incorporated → Mine #1; 1998-09-02 to 2000-01-19; source msha-controller-operator-history
- **controller_controls_operator:** Horizon Natural Resources Incorporated → Wolf Creek Collieries Company; 1998-09-02 to 2000-01-19; source msha-controller-operator-history
- **operator_operates_mine:** Peter Cave Mining Co. → Mine #1; 2000-01-20 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Massey Energy Company → Peter Cave Mining Co.; 2000-01-20 to 2011-05-31; source msha-controller-operator-history
- **controller_controls_mine:** Alpha Natural Resources, Inc. → Mine #1; 2011-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Alpha Natural Resources, Inc. → Peter Cave Mining Co.; 2011-06-01 to current/open; source msha-controller-operator-history