# Relationship history for MSHA mine 4200121

Current hierarchy: **Devin Jim  LeRoy → East Mountain Energy LLC → Deer Creek 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: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **controller_controls_mine:** Mc Arthur Shirl C → Deer Creek Mine; 1950-01-01 to 1979-05-11; source msha-controller-operator-history
- **operator_operates_mine:** Peabody Coal Company → Deer Creek Mine; 1950-01-01 to 1977-03-30; source msha-controller-operator-history
- **controller_controls_mine:** Kennecott Copper Corp → Deer Creek Mine; 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 → Deer Creek Mine; 1977-03-31 to 1979-04-30; source msha-controller-operator-history
- **controller_controls_operator:** Mc Arthur Shirl C → American Coal Company; 1977-03-31 to 1979-04-30; source msha-controller-operator-history
- **controller_controls_mine:** Savage Companies → Deer Creek Mine; 1979-03-21 to 1986-04-27; source msha-controller-operator-history
- **operator_operates_mine:** Emery Mining Corp → Deer Creek Mine; 1979-05-01 to 1986-04-27; source msha-controller-operator-history
- **controller_controls_operator:** Savage Companies → Emery Mining Corp; 1979-05-01 to 1986-04-27; source msha-controller-operator-history
- **operator_operates_mine:** Energy West Mining Company → Deer Creek Mine; 1986-04-28 to 2015-07-14; source msha-controller-operator-history
- **controller_controls_mine:** MidAmerican Energy Holdings Company → Deer Creek Mine; 1986-04-28 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** MidAmerican Energy Holdings Company → Energy West Mining Company; 1986-04-28 to 2015-07-14; source msha-controller-operator-history
- **operator_operates_mine:** East Mountain Energy LLC → Deer Creek Mine; 2015-07-15 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** John  Nielson et al → Deer Creek Mine; 2015-07-15 to 2016-08-17; source msha-controller-operator-history
- **controller_controls_operator:** John  Nielson et al → East Mountain Energy LLC; 2015-07-15 to 2016-08-17; source msha-controller-operator-history
- **controller_controls_operator:** Jesse  Nielson et al → East Mountain Energy LLC; 2015-07-15 to 2016-08-17; source msha-controller-operator-history
- **controller_controls_mine:** Devin Jim  LeRoy → Deer Creek Mine; 2016-08-18 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Devin Jim  LeRoy → East Mountain Energy LLC; 2016-08-18 to current/open; source msha-controller-operator-history