# Relationship history for MSHA mine 1512170

Current hierarchy: **Ocie A  May → Mare Creek Sand Co.,  Inc → No 1 Dredge**

- 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:** Mare Creek Sand Company Inc → No 1 Dredge; 1979-12-01 to 1993-08-31; source msha-controller-operator-history
- **controller_controls_mine:** David F  May → No 1 Dredge; 1979-12-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** David F  May → Mare Creek Sand Company Inc; 1979-12-01 to 1993-08-31; source msha-controller-operator-history
- **operator_operates_mine:** Mare Creek Sand Company Inc → No 1 Dredge; 1993-09-01 to 1996-09-22; source msha-controller-operator-history
- **controller_controls_mine:** Stewart  Vance → No 1 Dredge; 1993-09-01 to 1996-09-22; source msha-controller-operator-history
- **controller_controls_operator:** Stewart  Vance → Mare Creek Sand Company Inc; 1993-09-01 to 1996-09-22; source msha-controller-operator-history
- **operator_operates_mine:** Mare Creek Sand Company Inc → No 1 Dredge; 1996-09-23 to 2001-03-04; source msha-controller-operator-history
- **controller_controls_mine:** Bobby R  White → No 1 Dredge; 1996-09-23 to 2001-03-04; source msha-controller-operator-history
- **controller_controls_operator:** Bobby R  White → Mare Creek Sand Company Inc; 1996-09-23 to 2001-03-04; source msha-controller-operator-history
- **operator_operates_mine:** Mare Creek Sand Co.,  Inc → No 1 Dredge; 2001-03-05 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Ocie A  May → No 1 Dredge; 2001-03-05 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Ocie A  May → Mare Creek Sand Co.,  Inc; 2001-03-05 to current/open; source msha-controller-operator-history