# Relationship history for MSHA mine 3800387

Current hierarchy: **Martin Marietta Materials Inc → Palmetto Sand Company Inc → No 1 Mine**

- 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:** Palmetto Sand Company → No 1 Mine; 1950-01-01 to 1984-03-20; source msha-controller-operator-history
- **controller_controls_mine:** Sanders J G → No 1 Mine; 1950-01-01 to 1984-03-20; source msha-controller-operator-history
- **controller_controls_operator:** Sanders J G → Palmetto Sand Company; 1950-01-01 to 1984-03-20; source msha-controller-operator-history
- **operator_operates_mine:** Palmetto Sand Company Inc → No 1 Mine; 1984-03-21 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Florence H  Thomas → No 1 Mine; 1984-03-21 to 2006-11-30; source msha-controller-operator-history
- **controller_controls_operator:** Florence H  Thomas → Palmetto Sand Company Inc; 1984-03-21 to 2006-11-30; source msha-controller-operator-history
- **controller_controls_mine:** Hamer P Thomas → No 1 Mine; 2006-12-01 to 2018-10-25; source msha-controller-operator-history
- **controller_controls_operator:** Hamer P Thomas → Palmetto Sand Company Inc; 2006-12-01 to 2018-10-25; source msha-controller-operator-history
- **controller_controls_mine:** Blue Water Industries Holdings LLC → No 1 Mine; 2018-10-26 to 2024-04-04; source msha-controller-operator-history
- **controller_controls_operator:** Blue Water Industries Holdings LLC → Palmetto Sand Company Inc; 2018-10-26 to 2024-04-04; source msha-controller-operator-history
- **controller_controls_mine:** Martin Marietta Materials Inc → No 1 Mine; 2024-04-05 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Martin Marietta Materials Inc → Palmetto Sand Company Inc; 2024-04-05 to current/open; source msha-controller-operator-history