# Relationship history for MSHA mine 2800992

Current hierarchy: **William F Wismer → Penn Jersey Paving Materials Inc → Schafer'S 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: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **controller_controls_mine:** William F Wismer → Schafer'S Pit; 1991-04-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Penn Jersey Paving Materials Inc → Schafer'S Pit; 1991-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** William F Wismer → Penn Jersey Paving Materials Inc; 1991-06-01 to current/open; source msha-controller-operator-history