# Relationship history for MSHA mine 4300375

Current hierarchy: **Richard  Colton → R J Colton Company Inc → Hinesburg 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:** Roland Ayer Excavating → Hinesburg Pit; 1984-07-01 to 1987-07-23; source msha-controller-operator-history
- **controller_controls_mine:** Ayer Roland → Hinesburg Pit; 1984-07-01 to 1987-07-23; source msha-controller-operator-history
- **controller_controls_operator:** Ayer Roland → Roland Ayer Excavating; 1984-07-01 to 1987-07-23; source msha-controller-operator-history
- **operator_operates_mine:** R J Colton Company Inc → Hinesburg Pit; 1987-07-24 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Richard  Colton → Hinesburg Pit; 1987-07-24 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Richard  Colton → R J Colton Company Inc; 1987-07-24 to current/open; source msha-controller-operator-history