# Relationship history for MSHA mine 0901115

Current hierarchy: **Thomas Mark  Carrington → Blue Steel Quarry Inc → BLUE STEEL QUARRY INC.**

- 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

- **operator_operates_mine:** Pristine Blue Quarry Inc → BLUE STEEL QUARRY INC.; 1999-01-01 to 1999-07-19; source msha-controller-operator-history
- **controller_controls_mine:** Peggy E Childs → BLUE STEEL QUARRY INC.; 1999-01-01 to 1999-07-19; source msha-controller-operator-history
- **controller_controls_operator:** Peggy E Childs → Pristine Blue Quarry Inc; 1999-01-01 to 1999-07-19; source msha-controller-operator-history
- **operator_operates_mine:** Blue Steel Quarry Inc → BLUE STEEL QUARRY INC.; 1999-07-20 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Thomas Mark  Carrington → BLUE STEEL QUARRY INC.; 1999-07-20 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Thomas Mark  Carrington → Blue Steel Quarry Inc; 1999-07-20 to current/open; source msha-controller-operator-history