# Relationship history for MSHA mine 2302191

Current hierarchy: **Welton  Schwent; John  Runk → West County Quarry → West County Quarry**

- 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:** West County Quarry → West County Quarry; 1999-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Welton  Schwent et al → West County Quarry; 1999-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Welton  Schwent et al → West County Quarry; 1999-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** John  Runk et al → West County Quarry; 1999-07-01 to current/open; source msha-controller-operator-history