# Relationship history for MSHA mine 4607236

Current hierarchy: **Massey Energy Company → Naoma Coal Company → No 1 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: 2026-10-13T11:19:05.459773+00:00

## Valid-time edges

- **controller_controls_mine:** Hanson PLC → No 1 Mine; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Brewster Thomas → No 1 Mine; 1980-08-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Peabody Coal Company → No 1 Mine; 1986-11-01 to 1991-07-28; source msha-controller-operator-history
- **controller_controls_operator:** Hanson PLC → Peabody Coal Company; 1986-11-01 to 1991-07-28; source msha-controller-operator-history
- **operator_operates_mine:** Toney'S Branch Coal Company → No 1 Mine; 1991-07-29 to 1994-10-11; source msha-controller-operator-history
- **controller_controls_operator:** Brewster Thomas → Toney'S Branch Coal Company; 1991-07-29 to 1994-10-11; source msha-controller-operator-history
- **controller_controls_mine:** Joby  Fields → No 1 Mine; 1994-02-22 to 1997-01-19; source msha-controller-operator-history
- **operator_operates_mine:** Augusta Processing Inc → No 1 Mine; 1994-10-12 to 1995-08-11; source msha-controller-operator-history
- **controller_controls_operator:** Joby  Fields → Augusta Processing Inc; 1994-10-12 to 1995-08-11; source msha-controller-operator-history
- **operator_operates_mine:** Naoma Coal Company → No 1 Mine; 1995-08-12 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Massey Energy Company → No 1 Mine; 1995-08-12 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Massey Energy Company → Naoma Coal Company; 1995-08-12 to current/open; source msha-controller-operator-history