# Relationship history for MSHA mine 2901771

Current hierarchy: **Vulcan Materials Company → CalMat Co → PENA BLANCA**

- 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:** Pena Blanca Limited Partnership → PENA BLANCA; 1979-01-01 to 1996-01-04; source msha-controller-operator-history
- **controller_controls_mine:** Naumburg Phil Et Al → PENA BLANCA; 1979-01-01 to 1996-01-04; source msha-controller-operator-history
- **controller_controls_operator:** Naumburg Phil Et Al → Pena Blanca Limited Partnership; 1979-01-01 to 1996-01-04; source msha-controller-operator-history
- **controller_controls_mine:** Redland Plc → PENA BLANCA; 1995-03-01 to 1998-02-10; source msha-controller-operator-history
- **operator_operates_mine:** Western Mobile Santa Fe Inc → PENA BLANCA; 1996-01-05 to 1998-02-10; source msha-controller-operator-history
- **controller_controls_operator:** Redland Plc → Western Mobile Santa Fe Inc; 1996-01-05 to 1998-02-10; source msha-controller-operator-history
- **operator_operates_mine:** Western Mobile Santa Fe Inc → PENA BLANCA; 1998-02-11 to 2014-08-28; source msha-controller-operator-history
- **controller_controls_mine:** Lafarge S A → PENA BLANCA; 1998-02-11 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Lafarge S A → Western Mobile Santa Fe Inc; 1998-02-11 to 2014-08-28; source msha-controller-operator-history
- **controller_controls_mine:** Legacy Vulcan Corp (Form:Vulcan Materials Co) → PENA BLANCA; 1999-01-06 to 2007-11-15; source msha-controller-operator-history
- **controller_controls_mine:** Vulcan Materials Company → PENA BLANCA; 2007-11-16 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** CalMat Co → PENA BLANCA; 2014-08-29 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Vulcan Materials Company → CalMat Co; 2014-08-29 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Legacy Vulcan Corp (Form:Vulcan Materials Co) → CalMat Co; 2014-08-29 to 2007-11-15; source msha-controller-operator-history