# Relationship history for MSHA mine 2301700

Current hierarchy: **Michael K Farmer; Elliott (Bud) E Farmer → Capital Quarries Company Inc → Plant #4-Rolla**

- 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

- **controller_controls_mine:** Eric S  Strope et al → Plant #4-Rolla; 1950-01-01 to 2011-04-18; source msha-controller-operator-history
- **controller_controls_mine:** Wendell  Curtman → Plant #4-Rolla; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Curtman Materials → Plant #4-Rolla; 1978-03-09 to 1997-11-30; source msha-controller-operator-history
- **controller_controls_operator:** Wendell  Curtman → Curtman Materials; 1978-03-09 to 1997-11-30; source msha-controller-operator-history
- **operator_operates_mine:** Capital Quarries Company Inc → Plant #4-Rolla; 1997-12-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Eric S  Strope et al → Capital Quarries Company Inc; 1997-12-01 to 2011-04-18; source msha-controller-operator-history
- **controller_controls_mine:** Elliott (Bud) E Farmer  et al → Plant #4-Rolla; 2011-04-19 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Elliott (Bud) E Farmer  et al → Capital Quarries Company Inc; 2011-04-19 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Michael K Farmer  et al → Capital Quarries Company Inc; 2011-04-19 to current/open; source msha-controller-operator-history