# Relationship history for MSHA mine 4801646

Current hierarchy: **MidAmerican Energy Holdings Company; IDACORP → Bridger Coal Company → Bridger Underground Coal 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:** IDACORP et al → Bridger Underground Coal Mine; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Bridger Coal Company → Bridger Underground Coal Mine; 2004-07-15 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** IDACORP et al → Bridger Coal Company; 2004-07-15 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** MidAmerican Energy Holdings Company et al → Bridger Coal Company; 2004-07-15 to current/open; source msha-controller-operator-history