# Relationship history for MSHA mine 2602031

Current hierarchy: **Rory L  Tibbals; Joyce E  Johnson → Remtech L L C → TRINITY MINE**

- 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:** United States Borax & Chemical Corp → TRINITY MINE; 1987-10-01 to 1995-08-31; source msha-controller-operator-history
- **controller_controls_mine:** Rio Tinto Zinc Corp Of America & Santa Fe Railroad → TRINITY MINE; 1987-10-01 to 1995-08-31; source msha-controller-operator-history
- **controller_controls_operator:** Rio Tinto Zinc Corp Of America & Santa Fe Railroad → United States Borax & Chemical Corp; 1987-10-01 to 1995-08-31; source msha-controller-operator-history
- **operator_operates_mine:** Remtech L L C → TRINITY MINE; 1995-09-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Joyce E  Johnson et al → TRINITY MINE; 1995-09-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Joyce E  Johnson et al → Remtech L L C; 1995-09-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Rory L  Tibbals et al → Remtech L L C; 1995-09-01 to current/open; source msha-controller-operator-history