# Relationship history for MSHA mine 1102841

Current hierarchy: **Lafarge S A → Western Sand & Gravel Company → DIMMICK PORTABLE**

- 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:** Lyle C  Sitterly Jr → DIMMICK PORTABLE; 1950-01-01 to 2006-10-05; source msha-controller-operator-history
- **operator_operates_mine:** Western Sand & Gravel Company → DIMMICK PORTABLE; 1986-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Lyle C  Sitterly Jr → Western Sand & Gravel Company; 1986-04-01 to 2006-10-05; source msha-controller-operator-history
- **controller_controls_mine:** Lafarge S A → DIMMICK PORTABLE; 2006-10-06 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Lafarge S A → Western Sand & Gravel Company; 2006-10-06 to current/open; source msha-controller-operator-history