# Relationship history for MSHA mine 3002715

Current hierarchy: **David J  Dalrymple → Dalrymple Gravel & Contracting Co Inc → Mc Donald 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

- **controller_controls_mine:** Dalrymple Holding Corp → Mc Donald Pit; 1950-01-01 to 2014-10-17; source msha-controller-operator-history
- **controller_controls_mine:** Mc Donald Edward M → Mc Donald Pit; 1979-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Ed Mc Donald Excavating Inc → Mc Donald Pit; 1986-03-01 to 2010-10-14; source msha-controller-operator-history
- **controller_controls_operator:** Mc Donald Edward M → Ed Mc Donald Excavating Inc; 1986-03-01 to 2010-10-14; source msha-controller-operator-history
- **operator_operates_mine:** Dalrymple Gravel & Contracting Co Inc → Mc Donald Pit; 2010-10-15 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Dalrymple Holding Corp → Dalrymple Gravel & Contracting Co Inc; 2010-10-15 to 2014-10-17; source msha-controller-operator-history
- **controller_controls_mine:** David J  Dalrymple → Mc Donald Pit; 2014-10-18 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** David J  Dalrymple → Dalrymple Gravel & Contracting Co Inc; 2014-10-18 to current/open; source msha-controller-operator-history