# Relationship history for MSHA mine 1518116

Current hierarchy: **American Electric Power Company Inc → AEP Kentucky Coal, L. L. C. → Walker Branch 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:** Donn A  Chickering → Walker Branch Mine; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Branham & Baker Coal Company Inc → Walker Branch Mine; 1998-11-01 to 2001-10-29; source msha-controller-operator-history
- **controller_controls_operator:** Donn A  Chickering → Branham & Baker Coal Company Inc; 1998-11-01 to 2001-10-29; source msha-controller-operator-history
- **controller_controls_mine:** Ocie A  May → Walker Branch Mine; 2001-09-21 to 2003-07-13; source msha-controller-operator-history
- **operator_operates_mine:** AEP Kentucky Coal, L. L. C. → Walker Branch Mine; 2001-10-30 to 2002-01-23; source msha-controller-operator-history
- **controller_controls_mine:** American Electric Power Company Inc → Walker Branch Mine; 2001-10-30 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** American Electric Power Company Inc → AEP Kentucky Coal, L. L. C.; 2001-10-30 to 2002-01-23; source msha-controller-operator-history
- **operator_operates_mine:** M & D Pipeline Incorporated → Walker Branch Mine; 2002-01-24 to 2003-09-25; source msha-controller-operator-history
- **controller_controls_operator:** Ocie A  May → M & D Pipeline Incorporated; 2002-01-24 to 2003-07-13; source msha-controller-operator-history
- **controller_controls_mine:** Susan  Branham → Walker Branch Mine; 2003-07-14 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Susan  Branham → M & D Pipeline Incorporated; 2003-07-14 to 2003-09-25; source msha-controller-operator-history
- **operator_operates_mine:** AEP Kentucky Coal, L. L. C. → Walker Branch Mine; 2003-09-26 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** American Electric Power Company Inc → AEP Kentucky Coal, L. L. C.; 2003-09-26 to current/open; source msha-controller-operator-history