# Relationship history for MSHA mine 1900283

Current hierarchy: **Mc Namara John H → Assonet Washed Sand & Stone Company → As&G-Assonet**

- 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:** Assonet Sand & Gravel Company → As&G-Assonet; 1950-01-01 to 1978-05-31; source msha-controller-operator-history
- **controller_controls_mine:** Clarke Warren → As&G-Assonet; 1950-01-01 to 1978-05-31; source msha-controller-operator-history
- **controller_controls_operator:** Clarke Warren → Assonet Sand & Gravel Company; 1950-01-01 to 1978-05-31; source msha-controller-operator-history
- **operator_operates_mine:** C & S Sand & Gravel Corp → As&G-Assonet; 1978-06-01 to 1989-04-05; source msha-controller-operator-history
- **controller_controls_mine:** David R  Smith Jr → As&G-Assonet; 1978-06-01 to 1989-04-05; source msha-controller-operator-history
- **controller_controls_operator:** David R  Smith Jr → C & S Sand & Gravel Corp; 1978-06-01 to 1989-04-05; source msha-controller-operator-history
- **operator_operates_mine:** Assonet Washed Sand & Stone Company → As&G-Assonet; 1989-04-06 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Mc Namara John H → As&G-Assonet; 1989-04-06 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Mc Namara John H → Assonet Washed Sand & Stone Company; 1989-04-06 to current/open; source msha-controller-operator-history