# Relationship history for MSHA mine 3608479

Current hierarchy: **Brentzel Cathy → Penn Balt Inc → Pennbalt Cleaning Plant & Refuse**

- 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:** Brentzel Cathy → Pennbalt Cleaning Plant & Refuse; 1991-11-16 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Hofrichter Thomas R → Pennbalt Cleaning Plant & Refuse; 1994-08-15 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Avella Mining Inc → Pennbalt Cleaning Plant & Refuse; 1994-09-01 to 1995-06-28; source msha-controller-operator-history
- **controller_controls_operator:** Hofrichter Thomas R → Avella Mining Inc; 1994-09-01 to 1995-06-28; source msha-controller-operator-history
- **operator_operates_mine:** Penn Balt Inc → Pennbalt Cleaning Plant & Refuse; 1995-06-29 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Brentzel Cathy → Penn Balt Inc; 1995-06-29 to current/open; source msha-controller-operator-history