# Relationship history for MSHA mine 3401253

Current hierarchy: **Adams J R & Jo Ann → Highway Contractors Inc → Shaffer Sand Pit**

- 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:** D & H Paving → Shaffer Sand Pit; 1980-03-01 to 1984-07-06; source msha-controller-operator-history
- **controller_controls_mine:** Henderson Don → Shaffer Sand Pit; 1980-03-01 to 1984-07-06; source msha-controller-operator-history
- **controller_controls_operator:** Henderson Don → D & H Paving; 1980-03-01 to 1984-07-06; source msha-controller-operator-history
- **operator_operates_mine:** Highway Contractors Inc → Shaffer Sand Pit; 1984-07-07 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Adams J R & Jo Ann → Shaffer Sand Pit; 1984-07-07 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Adams J R & Jo Ann → Highway Contractors Inc; 1984-07-07 to current/open; source msha-controller-operator-history