# Relationship history for MSHA mine 2302004

Current hierarchy: **Martin Marietta Materials Inc → Martin Marietta Materials, Inc. → Huntsville Quarry**

- 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:** Green Quarries Inc → Huntsville Quarry; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Martin Marietta Materials Inc → Huntsville Quarry; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Green Quarries Inc → Huntsville Quarry; 1989-05-01 to 1999-07-31; source msha-controller-operator-history
- **controller_controls_operator:** Green Quarries Inc → Green Quarries Inc; 1989-05-01 to 1999-07-31; source msha-controller-operator-history
- **controller_controls_mine:** Brady D  Meldrem → Huntsville Quarry; 1997-01-20 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Norris Asphalt Paving Company → Huntsville Quarry; 1999-08-01 to 2012-02-28; source msha-controller-operator-history
- **controller_controls_operator:** Brady D  Meldrem → Norris Asphalt Paving Company; 1999-08-01 to 2012-02-28; source msha-controller-operator-history
- **controller_controls_mine:** Con-Agg Llc → Huntsville Quarry; 2001-12-28 to 2010-09-14; source msha-controller-operator-history
- **controller_controls_mine:** Summit Materials LLC → Huntsville Quarry; 2010-09-15 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Norris Quarries, LLC → Huntsville Quarry; 2012-02-29 to 2013-01-25; source msha-controller-operator-history
- **controller_controls_mine:** Summit Materials LLC → Huntsville Quarry; 2012-02-29 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Summit Materials LLC → Norris Quarries, LLC; 2012-02-29 to 2013-01-25; source msha-controller-operator-history
- **operator_operates_mine:** Con-Agg Companies, LLC → Huntsville Quarry; 2013-01-26 to 2026-03-22; source msha-controller-operator-history
- **controller_controls_operator:** Con-Agg Llc → Con-Agg Companies, LLC; 2013-01-26 to 2010-09-14; source msha-controller-operator-history
- **controller_controls_operator:** Summit Materials LLC → Con-Agg Companies, LLC; 2013-01-26 to 2026-03-22; source msha-controller-operator-history
- **operator_operates_mine:** Martin Marietta Materials, Inc. → Huntsville Quarry; 2026-03-23 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Martin Marietta Materials Inc → Martin Marietta Materials, Inc.; 2026-03-23 to current/open; source msha-controller-operator-history