# Relationship history for MSHA mine 4300156

Current hierarchy: **Ormond  Bushey Jr → Ormond Bushey & Sons Inc → FAIRFAX SAND & GRAVEL**

- 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:** Robert O Ovitt → FAIRFAX SAND & GRAVEL; 1950-01-01 to 1981-10-27; source msha-controller-operator-history
- **controller_controls_mine:** Robert  Ovitt et al → FAIRFAX SAND & GRAVEL; 1950-01-01 to 1981-10-27; source msha-controller-operator-history
- **controller_controls_operator:** Robert  Ovitt et al → Robert O Ovitt; 1950-01-01 to 1981-10-27; source msha-controller-operator-history
- **controller_controls_mine:** Ormond  Bushey Jr → FAIRFAX SAND & GRAVEL; 1980-03-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Fairfax Sand & Gravel Company → FAIRFAX SAND & GRAVEL; 1981-10-28 to 1984-09-17; source msha-controller-operator-history
- **controller_controls_mine:** Edmund N  Hathaway  et al → FAIRFAX SAND & GRAVEL; 1981-10-28 to 1984-09-17; source msha-controller-operator-history
- **controller_controls_operator:** Edmund N  Hathaway  et al → Fairfax Sand & Gravel Company; 1981-10-28 to 1984-09-17; source msha-controller-operator-history
- **operator_operates_mine:** Ormond Bushey & Sons Inc → FAIRFAX SAND & GRAVEL; 1984-09-18 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Ormond  Bushey Jr → Ormond Bushey & Sons Inc; 1984-09-18 to current/open; source msha-controller-operator-history