# Relationship history for MSHA mine 3502491

Current hierarchy: **Howard M  Day → Hooker Creek Companies, LLC → SP-9 O'NEIL**

- 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:** O'Neil Sand & Gravel Company → SP-9 O'NEIL; 1950-01-01 to 1992-09-30; source msha-controller-operator-history
- **controller_controls_mine:** Emil  Howard → SP-9 O'NEIL; 1950-01-01 to 1992-09-30; source msha-controller-operator-history
- **controller_controls_operator:** Emil  Howard → O'Neil Sand & Gravel Company; 1950-01-01 to 1992-09-30; source msha-controller-operator-history
- **operator_operates_mine:** Arco Construction Company Inc → SP-9 O'NEIL; 1992-10-01 to 1996-01-31; source msha-controller-operator-history
- **controller_controls_mine:** John  Arnett → SP-9 O'NEIL; 1992-10-01 to 1996-01-31; source msha-controller-operator-history
- **controller_controls_operator:** John  Arnett → Arco Construction Company Inc; 1992-10-01 to 1996-01-31; source msha-controller-operator-history
- **controller_controls_mine:** Howard M  Day → SP-9 O'NEIL; 1995-05-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Hooker Creek Companies, LLC → SP-9 O'NEIL; 1996-02-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Howard M  Day → Hooker Creek Companies, LLC; 1996-02-01 to current/open; source msha-controller-operator-history