# Relationship history for MSHA mine 1001828

Current hierarchy: **CRH PLC → Bannock Paving Company Inc → Portable #2**

- 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

- **controller_controls_mine:** Bill  Hunziker → Portable #2; 1987-05-21 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Moncar Construction Inc → Portable #2; 1988-06-01 to 1991-03-31; source msha-controller-operator-history
- **controller_controls_mine:** Seth  Carpenter → Portable #2; 1988-06-01 to 1991-03-31; source msha-controller-operator-history
- **controller_controls_operator:** Seth  Carpenter → Moncar Construction Inc; 1988-06-01 to 1991-03-31; source msha-controller-operator-history
- **operator_operates_mine:** Hunziker Construction Company → Portable #2; 1991-04-01 to 1999-06-09; source msha-controller-operator-history
- **controller_controls_operator:** Bill  Hunziker → Hunziker Construction Company; 1991-04-01 to 1999-06-09; source msha-controller-operator-history
- **controller_controls_mine:** CRH PLC → Portable #2; 1996-04-02 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Bannock Paving Company Inc → Portable #2; 1999-06-10 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** CRH PLC → Bannock Paving Company Inc; 1999-06-10 to current/open; source msha-controller-operator-history