# Relationship history for MSHA mine 2400474

Current hierarchy: **JTL Group Inc → Western Materials → Crusher #1 - Grant Creek**

- 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:** Western Materials Inc → Crusher #1 - Grant Creek; 1950-01-01 to 1990-06-30; source msha-controller-operator-history
- **controller_controls_mine:** United Companies → Crusher #1 - Grant Creek; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** United Companies → Western Materials Inc; 1950-01-01 to 1990-06-30; source msha-controller-operator-history
- **operator_operates_mine:** Western Materials → Crusher #1 - Grant Creek; 1990-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** JTL Group Inc → Crusher #1 - Grant Creek; 1990-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** JTL Group Inc → Western Materials; 1990-07-01 to current/open; source msha-controller-operator-history