# Relationship history for MSHA mine 0102804

Current hierarchy: **Frank N  Harrison; Beverly  Harrison → Huntsville Gravel Company Llc → HUNTSVILLE GRAVEL CO.**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-18T09:31:49.615908+00:00

## Valid-time edges

- **operator_operates_mine:** Vulcan Sand & Gravel - Vulcan Materials Company → HUNTSVILLE GRAVEL CO.; 1989-05-01 to 1996-05-31; source msha-controller-operator-history
- **controller_controls_mine:** Legacy Vulcan Corp (Form:Vulcan Materials Co) → HUNTSVILLE GRAVEL CO.; 1989-05-01 to 1996-05-31; source msha-controller-operator-history
- **controller_controls_operator:** Legacy Vulcan Corp (Form:Vulcan Materials Co) → Vulcan Sand & Gravel - Vulcan Materials Company; 1989-05-01 to 1996-05-31; source msha-controller-operator-history
- **operator_operates_mine:** Huntsville Gravel Company Llc → HUNTSVILLE GRAVEL CO.; 1996-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Beverly  Harrison et al → HUNTSVILLE GRAVEL CO.; 1996-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Beverly  Harrison et al → Huntsville Gravel Company Llc; 1996-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Frank N  Harrison et al → Huntsville Gravel Company Llc; 1996-06-01 to current/open; source msha-controller-operator-history