# Relationship history for MSHA mine 4202637

Current hierarchy: **Summit Materials LLC → Kilgore Contracting → Grantsville 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:** Harold  Elam → Grantsville Pit; 1950-01-01 to 2011-03-31; source msha-controller-operator-history
- **controller_controls_mine:** Summit Materials LLC → Grantsville Pit; 2011-04-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Metro Ready Mix LLC → Grantsville Pit; 2014-09-25 to 2018-01-06; source msha-controller-operator-history
- **controller_controls_mine:** John  Dunn → Grantsville Pit; 2014-09-25 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** John  Dunn → Metro Ready Mix LLC; 2014-09-25 to 2018-01-06; source msha-controller-operator-history
- **operator_operates_mine:** Kilgore Contracting → Grantsville Pit; 2018-01-07 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Harold  Elam → Kilgore Contracting; 2018-01-07 to 2011-03-31; source msha-controller-operator-history
- **controller_controls_operator:** Summit Materials LLC → Kilgore Contracting; 2018-01-07 to current/open; source msha-controller-operator-history