# Relationship history for MSHA mine 1500095

Current hierarchy: **Martin Marietta Materials Inc → Bluegrass Materials Company, LLC → Hartford 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: 2026-10-13T11:19:05.459773+00:00

## Valid-time edges

- **operator_operates_mine:** State Contracting & Materials Division → Hartford Quarry; 1950-01-01 to 1978-12-31; source msha-controller-operator-history
- **controller_controls_mine:** Medusa Corp → Hartford Quarry; 1950-01-01 to 1979-01-31; source msha-controller-operator-history
- **controller_controls_operator:** Medusa Corp → State Contracting & Materials Division; 1950-01-01 to 1978-12-31; source msha-controller-operator-history
- **controller_controls_mine:** Medusa Corp → Hartford Quarry; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Southdown Inc → Hartford Quarry; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Crane Company → Hartford Quarry; 1978-12-13 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Medusa Aggregates Company → Hartford Quarry; 1979-01-01 to 1988-10-06; source msha-controller-operator-history
- **controller_controls_operator:** Crane Company → Medusa Aggregates Company; 1979-01-01 to 1988-10-06; source msha-controller-operator-history
- **operator_operates_mine:** Medusa Aggregates Company → Hartford Quarry; 1988-10-07 to 1998-06-29; source msha-controller-operator-history
- **controller_controls_operator:** Medusa Corp → Medusa Aggregates Company; 1988-10-07 to 1998-06-29; source msha-controller-operator-history
- **controller_controls_mine:** Cemex S A → Hartford Quarry; 1994-09-09 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Southdown Inc → Hartford Quarry; 1998-06-30 to 2000-11-02; source msha-controller-operator-history
- **controller_controls_operator:** Southdown Inc → Southdown Inc; 1998-06-30 to 2000-11-02; source msha-controller-operator-history
- **controller_controls_mine:** CSR Ltd → Hartford Quarry; 2000-07-01 to 2003-03-31; source msha-controller-operator-history
- **operator_operates_mine:** Cemex Inc → Hartford Quarry; 2000-11-03 to 2002-03-31; source msha-controller-operator-history
- **controller_controls_operator:** Cemex S A → Cemex Inc; 2000-11-03 to 2002-03-31; source msha-controller-operator-history
- **operator_operates_mine:** Rinker Materials South Central, Inc. → Hartford Quarry; 2002-04-01 to 2008-08-19; source msha-controller-operator-history
- **controller_controls_operator:** CSR Ltd → Rinker Materials South Central, Inc.; 2002-04-01 to 2003-03-31; source msha-controller-operator-history
- **controller_controls_mine:** Rinker Group Ltd → Hartford Quarry; 2003-04-01 to 2007-07-09; source msha-controller-operator-history
- **controller_controls_operator:** Rinker Group Ltd → Rinker Materials South Central, Inc.; 2003-04-01 to 2007-07-09; source msha-controller-operator-history
- **controller_controls_mine:** Cemex S A → Hartford Quarry; 2007-07-10 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Cemex S A → Rinker Materials South Central, Inc.; 2007-07-10 to 2008-08-19; source msha-controller-operator-history
- **operator_operates_mine:** Cemex Construction Materials Atlantic LLC → Hartford Quarry; 2008-08-20 to 2010-08-25; source msha-controller-operator-history
- **controller_controls_mine:** Cemex S A → Hartford Quarry; 2008-08-20 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Cemex S A → Cemex Construction Materials Atlantic LLC; 2008-08-20 to 2010-08-25; source msha-controller-operator-history
- **operator_operates_mine:** Bluegrass Materials Company, LLC → Hartford Quarry; 2010-08-26 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Panadero Aggregates Holdings, LLC → Hartford Quarry; 2010-08-26 to 2018-04-26; source msha-controller-operator-history
- **controller_controls_operator:** Panadero Aggregates Holdings, LLC → Bluegrass Materials Company, LLC; 2010-08-26 to 2018-04-26; source msha-controller-operator-history
- **controller_controls_mine:** Martin Marietta Materials Inc → Hartford Quarry; 2018-04-27 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Martin Marietta Materials Inc → Bluegrass Materials Company, LLC; 2018-04-27 to current/open; source msha-controller-operator-history