# Relationship history for MSHA mine 4200080

Current hierarchy: **MidAmerican Energy Holdings Company → Utah Power & Light Company-Mining Division → Wilberg**

- 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:** Mc Arthur Shirl C → Wilberg; 1950-01-01 to 1979-05-11; source msha-controller-operator-history
- **operator_operates_mine:** Peabody Coal Company → Wilberg; 1950-01-01 to 1977-03-30; source msha-controller-operator-history
- **controller_controls_mine:** Kennecott Copper Corp → Wilberg; 1950-01-01 to 1977-06-30; source msha-controller-operator-history
- **controller_controls_operator:** Kennecott Copper Corp → Peabody Coal Company; 1950-01-01 to 1977-03-30; source msha-controller-operator-history
- **operator_operates_mine:** American Coal Company → Wilberg; 1977-03-31 to 1979-05-11; source msha-controller-operator-history
- **controller_controls_operator:** Mc Arthur Shirl C → American Coal Company; 1977-03-31 to 1979-05-11; source msha-controller-operator-history
- **controller_controls_mine:** Savage Companies → Wilberg; 1979-03-21 to 1986-04-27; source msha-controller-operator-history
- **operator_operates_mine:** Emery Mining Corp → Wilberg; 1979-05-12 to 1986-04-27; source msha-controller-operator-history
- **controller_controls_operator:** Savage Companies → Emery Mining Corp; 1979-05-12 to 1986-04-27; source msha-controller-operator-history
- **operator_operates_mine:** Utah Power & Light Company-Mining Division → Wilberg; 1986-04-28 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** MidAmerican Energy Holdings Company → Wilberg; 1986-04-28 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** MidAmerican Energy Holdings Company → Utah Power & Light Company-Mining Division; 1986-04-28 to current/open; source msha-controller-operator-history