# Relationship history for MSHA mine 1301927

Current hierarchy: **Thomas R  Scott → River Products Company Inc → RIVERSIDE SAND PLANT & 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:** Thomas R  Scott et al → RIVERSIDE SAND PLANT & PIT; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** John M  Stevens Jr → RIVERSIDE SAND PLANT & PIT; 1950-01-01 to 1991-03-26; source msha-controller-operator-history
- **operator_operates_mine:** Stevens Sand & Gravel Company Inc → RIVERSIDE SAND PLANT & PIT; 1980-05-01 to 1989-10-09; source msha-controller-operator-history
- **controller_controls_operator:** John M  Stevens Jr → Stevens Sand & Gravel Company Inc; 1980-05-01 to 1989-10-09; source msha-controller-operator-history
- **operator_operates_mine:** River Products Company Inc → RIVERSIDE SAND PLANT & PIT; 1989-10-10 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Thomas R  Scott et al → River Products Company Inc; 1989-10-10 to current/open; source msha-controller-operator-history