# Relationship history for MSHA mine 1512856

Current hierarchy: **Johnson Burl → Cow Creek Construction Company Inc → Cow Creek Const Co Inc #2**

- 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:** Conley Bert R & Fon Martin → Cow Creek Const Co Inc #2; 1981-04-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** R & T Coal Company → Cow Creek Const Co Inc #2; 1981-05-01 to 1982-06-23; source msha-controller-operator-history
- **controller_controls_operator:** Conley Bert R & Fon Martin → R & T Coal Company; 1981-05-01 to 1982-06-23; source msha-controller-operator-history
- **controller_controls_mine:** Johnson Burl → Cow Creek Const Co Inc #2; 1982-06-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Cow Creek Construction Company Inc → Cow Creek Const Co Inc #2; 1982-06-24 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Johnson Burl → Cow Creek Construction Company Inc; 1982-06-24 to current/open; source msha-controller-operator-history