# Relationship history for MSHA mine 0900073

Current hierarchy: **Holliday John W & Garnett M → Holliday Construction Company → Beaverdam Creek 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: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** Welch & Worley Granite Company Inc → Beaverdam Creek Quarry; 1950-01-01 to 1981-07-13; source msha-controller-operator-history
- **controller_controls_mine:** Speed  Worley → Beaverdam Creek Quarry; 1950-01-01 to 1981-07-13; source msha-controller-operator-history
- **controller_controls_operator:** Speed  Worley → Welch & Worley Granite Company Inc; 1950-01-01 to 1981-07-13; source msha-controller-operator-history
- **controller_controls_mine:** Holliday John W & Garnett M → Beaverdam Creek Quarry; 1980-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Holliday Construction Company → Beaverdam Creek Quarry; 1981-07-14 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Holliday John W & Garnett M → Holliday Construction Company; 1981-07-14 to current/open; source msha-controller-operator-history