# Relationship history for MSHA mine 2200659

Current hierarchy: **Paula  Johnston; Donna L  Byrd → Johnston's Sand & Gravel Inc Pit #5 → Johnston's Sand & Gravel Inc Pit #5**

- 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

- **controller_controls_mine:** Michael A  Bush  et al → Johnston's Sand & Gravel Inc Pit #5; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Donna L  Byrd et al → Johnston's Sand & Gravel Inc Pit #5; 1979-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Mid-South Sand & Gravel Inc → Johnston's Sand & Gravel Inc Pit #5; 1994-04-01 to 1994-08-07; source msha-controller-operator-history
- **controller_controls_mine:** Thomas L  Tullos → Johnston's Sand & Gravel Inc Pit #5; 1994-04-01 to 1994-08-07; source msha-controller-operator-history
- **controller_controls_operator:** Thomas L  Tullos → Mid-South Sand & Gravel Inc; 1994-04-01 to 1994-08-07; source msha-controller-operator-history
- **operator_operates_mine:** Bush Construction Company Inc → Johnston's Sand & Gravel Inc Pit #5; 1994-08-08 to 2004-08-09; source msha-controller-operator-history
- **controller_controls_operator:** Michael A  Bush  et al → Bush Construction Company Inc; 1994-08-08 to 2004-08-09; source msha-controller-operator-history
- **operator_operates_mine:** Johnston's Sand & Gravel Inc Pit #5 → Johnston's Sand & Gravel Inc Pit #5; 2004-08-10 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Donna L  Byrd et al → Johnston's Sand & Gravel Inc Pit #5; 2004-08-10 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Paula  Johnston et al → Johnston's Sand & Gravel Inc Pit #5; 2004-08-10 to current/open; source msha-controller-operator-history