# Relationship history for MSHA mine 2302130

Current hierarchy: **Don J  Summers; Rebecca L  Summers → S & A Construction Ltd → Big Creek Quarry**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** S & A Construction Ltd → Big Creek Quarry; 1995-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Don J  Summers et al → Big Creek Quarry; 1995-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Don J  Summers et al → S & A Construction Ltd; 1995-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Rebecca L  Summers et al → S & A Construction Ltd; 1995-07-01 to current/open; source msha-controller-operator-history