# Relationship history for MSHA mine 1800755

Current hierarchy: **Everett W  Oester → Casselman Valley Ledgestone → Fresh 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:** Michael C Miscovich → Fresh Quarry; 2001-08-01 to 2008-08-06; source msha-controller-operator-history
- **controller_controls_mine:** Michael C  Miscovich → Fresh Quarry; 2001-08-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Michael C  Miscovich → Michael C Miscovich; 2001-08-01 to 2008-08-06; source msha-controller-operator-history
- **operator_operates_mine:** Casselman Valley Ledgestone → Fresh Quarry; 2008-08-07 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Everett W  Oester → Fresh Quarry; 2008-08-07 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Everett W  Oester → Casselman Valley Ledgestone; 2008-08-07 to current/open; source msha-controller-operator-history