# Relationship history for MSHA mine 0202633

Current hierarchy: **Michael  Denny → MDI Mining → Dewey Plant**

- 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

- **operator_operates_mine:** Mingus Rock → Dewey Plant; 1994-09-01 to 1997-07-13; source msha-controller-operator-history
- **controller_controls_mine:** Richard  Halliburton et al → Dewey Plant; 1994-09-01 to 1997-07-13; source msha-controller-operator-history
- **controller_controls_operator:** Richard  Halliburton et al → Mingus Rock; 1994-09-01 to 1997-07-13; source msha-controller-operator-history
- **operator_operates_mine:** MDI Mining → Dewey Plant; 1997-07-14 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Michael  Denny → Dewey Plant; 1997-07-14 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Michael  Denny → MDI Mining; 1997-07-14 to current/open; source msha-controller-operator-history