# Relationship history for MSHA mine 1518021

Current hierarchy: **Ricky D  Kirk; Jerry  Wells Jr → Carbon River Coal Corp → Mine #5**

- 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:** Ricky D  Kirk  et al → Mine #5; 1984-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** William B  Sturgill → Mine #5; 1987-08-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Big Elk Creek Coal Company Inc → Mine #5; 1998-02-01 to 1999-08-31; source msha-controller-operator-history
- **controller_controls_operator:** William B  Sturgill → Big Elk Creek Coal Company Inc; 1998-02-01 to 1999-08-31; source msha-controller-operator-history
- **operator_operates_mine:** Carbon River Coal Corp → Mine #5; 1999-09-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Ricky D  Kirk  et al → Carbon River Coal Corp; 1999-09-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Jerry  Wells Jr  et al → Carbon River Coal Corp; 1999-09-01 to current/open; source msha-controller-operator-history