# Relationship history for MSHA mine 0202524

Current hierarchy: **Martin Marietta Materials Inc → Martin Marietta Materials, Inc → Clarkdale Plant #24**

- 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:** Martin Marietta Materials Inc → Clarkdale Plant #24; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Norman D  Heath → Clarkdale Plant #24; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Hanson PLC → Clarkdale Plant #24; 1988-11-14 to 2007-08-22; source msha-controller-operator-history
- **operator_operates_mine:** Valley Concrete & Materials Inc → Clarkdale Plant #24; 1990-05-01 to 1999-12-29; source msha-controller-operator-history
- **controller_controls_operator:** Norman D  Heath → Valley Concrete & Materials Inc; 1990-05-01 to 1999-12-29; source msha-controller-operator-history
- **controller_controls_mine:** Pioneer International Ltd → Clarkdale Plant #24; 1997-09-01 to 2000-08-03; source msha-controller-operator-history
- **operator_operates_mine:** Pioneer Concrete Of Arizona Inc → Clarkdale Plant #24; 1999-12-30 to 2000-08-03; source msha-controller-operator-history
- **controller_controls_operator:** Pioneer International Ltd → Pioneer Concrete Of Arizona Inc; 1999-12-30 to 2000-08-03; source msha-controller-operator-history
- **operator_operates_mine:** Hanson Aggregates Arizona, Inc → Clarkdale Plant #24; 2000-08-04 to 2010-05-02; source msha-controller-operator-history
- **controller_controls_mine:** Hanson PLC → Clarkdale Plant #24; 2000-08-04 to 2007-08-22; source msha-controller-operator-history
- **controller_controls_operator:** Hanson PLC → Hanson Aggregates Arizona, Inc; 2000-08-04 to 2007-08-22; source msha-controller-operator-history
- **controller_controls_mine:** Heidelberg Materials AG → Clarkdale Plant #24; 2007-08-23 to 2021-09-30; source msha-controller-operator-history
- **controller_controls_mine:** Heidelberg Materials AG → Clarkdale Plant #24; 2007-08-23 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Heidelberg Materials AG → Hanson Aggregates Arizona, Inc; 2007-08-23 to 2010-05-02; source msha-controller-operator-history
- **operator_operates_mine:** Hanson Aggregates LLC → Clarkdale Plant #24; 2010-05-03 to 2022-05-29; source msha-controller-operator-history
- **controller_controls_operator:** Heidelberg Materials AG → Hanson Aggregates LLC; 2010-05-03 to 2021-09-30; source msha-controller-operator-history
- **controller_controls_operator:** Hanson PLC → Hanson Aggregates LLC; 2010-05-03 to 2007-08-22; source msha-controller-operator-history
- **controller_controls_mine:** Martin Marietta Materials Inc → Clarkdale Plant #24; 2021-10-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Martin Marietta Materials Inc → Hanson Aggregates LLC; 2021-10-01 to 2022-05-29; source msha-controller-operator-history
- **operator_operates_mine:** Martin Marietta Materials, Inc → Clarkdale Plant #24; 2022-05-30 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Martin Marietta Materials Inc → Martin Marietta Materials, Inc; 2022-05-30 to current/open; source msha-controller-operator-history