# Relationship history for MSHA mine 2700150

Current hierarchy: **R David  Schelzi → Coastal Materials Corp → Rochester Pit And Mill**

- 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:** Rochester Sand & Gravel Company → Rochester Pit And Mill; 1950-01-01 to 1978-04-24; source msha-controller-operator-history
- **controller_controls_mine:** Rochester Sand & Gravel Company → Rochester Pit And Mill; 1950-01-01 to 1978-04-24; source msha-controller-operator-history
- **controller_controls_operator:** Rochester Sand & Gravel Company → Rochester Sand & Gravel Company; 1950-01-01 to 1978-04-24; source msha-controller-operator-history
- **operator_operates_mine:** Coastal Materials Corp → Rochester Pit And Mill; 1978-04-25 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** R David  Schelzi → Rochester Pit And Mill; 1978-04-25 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** R David  Schelzi → Coastal Materials Corp; 1978-04-25 to current/open; source msha-controller-operator-history