# Relationship history for MSHA mine 1512756

Current hierarchy: **Baker John D & Quentin Yeager → B J Coal Company → B J #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:** B J Coal Company → B J #1; 1981-02-01 to 1981-05-04; source msha-controller-operator-history
- **controller_controls_mine:** Brumley Carlos & Roy Peak Et Al → B J #1; 1981-02-01 to 1981-05-04; source msha-controller-operator-history
- **controller_controls_operator:** Brumley Carlos & Roy Peak Et Al → B J Coal Company; 1981-02-01 to 1981-05-04; source msha-controller-operator-history
- **operator_operates_mine:** B J Coal Company → B J #1; 1981-05-05 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Baker John D & Quentin Yeager → B J #1; 1981-05-05 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Baker John D & Quentin Yeager → B J Coal Company; 1981-05-05 to current/open; source msha-controller-operator-history