# Relationship history for MSHA mine 3401652

Current hierarchy: **Cherokee County-Ok → Cherokee County → TAHLEQUAH PITT #1**

- 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:** Bryan Sand & Gravel Company → TAHLEQUAH PITT #1; 1988-07-01 to 1989-03-29; source msha-controller-operator-history
- **controller_controls_mine:** Bryan T L → TAHLEQUAH PITT #1; 1988-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Bryan T L → Bryan Sand & Gravel Company; 1988-07-01 to 1989-03-29; source msha-controller-operator-history
- **operator_operates_mine:** Ryals Gravel → TAHLEQUAH PITT #1; 1989-03-30 to 2001-01-03; source msha-controller-operator-history
- **controller_controls_mine:** Ryals Phillip → TAHLEQUAH PITT #1; 1989-03-30 to 2001-01-03; source msha-controller-operator-history
- **controller_controls_operator:** Ryals Phillip → Ryals Gravel; 1989-03-30 to 2001-01-03; source msha-controller-operator-history
- **operator_operates_mine:** Cherokee County → TAHLEQUAH PITT #1; 2001-01-04 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Cherokee County-Ok → TAHLEQUAH PITT #1; 2001-01-04 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Cherokee County-Ok → Cherokee County; 2001-01-04 to current/open; source msha-controller-operator-history