# Relationship history for MSHA mine 2700158

Current hierarchy: **CRH PLC → Pike Industries Inc → Twin Mountain Sand & Gravel (C609)**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-18T09:31:49.615908+00:00

## Valid-time edges

- **operator_operates_mine:** Twin Mountain Sand & Gravel Inc → Twin Mountain Sand & Gravel (C609); 1950-01-01 to 1986-11-24; source msha-controller-operator-history
- **controller_controls_mine:** Arthur Whitcomb Inc → Twin Mountain Sand & Gravel (C609); 1950-01-01 to 1986-11-24; source msha-controller-operator-history
- **controller_controls_operator:** Arthur Whitcomb Inc → Twin Mountain Sand & Gravel Inc; 1950-01-01 to 1986-11-24; source msha-controller-operator-history
- **operator_operates_mine:** Twin Mountain Sand & Gravel → Twin Mountain Sand & Gravel (C609); 1986-11-25 to 1996-12-31; source msha-controller-operator-history
- **controller_controls_mine:** BTR PLC → Twin Mountain Sand & Gravel (C609); 1986-11-25 to 1996-12-31; source msha-controller-operator-history
- **controller_controls_operator:** BTR PLC → Twin Mountain Sand & Gravel; 1986-11-25 to 1996-12-31; source msha-controller-operator-history
- **controller_controls_mine:** CRH PLC → Twin Mountain Sand & Gravel (C609); 1988-06-02 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Pike Industries Inc → Twin Mountain Sand & Gravel (C609); 1997-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** CRH PLC → Pike Industries Inc; 1997-01-01 to current/open; source msha-controller-operator-history