# Relationship history for MSHA mine 3607202

Current hierarchy: **Joseph  Podunajec → Lake Ladore Sand & Gravel Inc → Roberts Thomas 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

- **operator_operates_mine:** Lake Ladore Sand & Gravel Inc → Roberts Thomas Pit; 1981-09-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Joseph  Podunajec et al → Roberts Thomas Pit; 1981-09-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Joseph  Podunajec et al → Lake Ladore Sand & Gravel Inc; 1981-09-01 to current/open; source msha-controller-operator-history