# Relationship history for MSHA mine 3602736

Current hierarchy: **Dale  Augenstein; Richard  Thornhill → K & J Coal Company Inc → Westover #3 Strip**

- 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

- **operator_operates_mine:** K & J Coal Company Inc → Westover #3 Strip; 1950-01-01 to 1988-08-14; source msha-controller-operator-history
- **controller_controls_mine:** Canterra Coal Inc → Westover #3 Strip; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Canterra Coal Inc → K & J Coal Company Inc; 1950-01-01 to 1988-08-14; source msha-controller-operator-history
- **operator_operates_mine:** K & J Coal Company Inc → Westover #3 Strip; 1988-08-15 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Richard  Thornhill et al → Westover #3 Strip; 1988-08-15 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Richard  Thornhill et al → K & J Coal Company Inc; 1988-08-15 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Dale  Augenstein et al → K & J Coal Company Inc; 1988-08-15 to current/open; source msha-controller-operator-history