# Relationship history for MSHA mine 3000820

Current hierarchy: **New Enterprise Stone & Lime Company Inc → New Enterprise Stone and Lime Co. Inc. → Franklinville Sand and Gravel**

- 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:** Buffalo Slag Company Inc → Franklinville Sand and Gravel; 1950-01-01 to 1986-09-28; source msha-controller-operator-history
- **controller_controls_mine:** Koppers Company Inc → Franklinville Sand and Gravel; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Koppers Company Inc → Buffalo Slag Company Inc; 1950-01-01 to 1986-09-28; source msha-controller-operator-history
- **controller_controls_mine:** New Enterprise Stone & Lime Company Inc → Franklinville Sand and Gravel; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** R E  Garman  et al → Franklinville Sand and Gravel; 1978-10-31 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Buffalo Crushed Stone Company Inc → Franklinville Sand and Gravel; 1986-09-29 to 2000-07-31; source msha-controller-operator-history
- **controller_controls_operator:** R E  Garman  et al → Buffalo Crushed Stone Company Inc; 1986-09-29 to 2000-07-31; source msha-controller-operator-history
- **operator_operates_mine:** Buffalo Crushed Stone Company Inc → Franklinville Sand and Gravel; 2000-08-01 to 2010-12-31; source msha-controller-operator-history
- **controller_controls_mine:** New Enterprise Stone & Lime Company Inc → Franklinville Sand and Gravel; 2000-08-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** New Enterprise Stone & Lime Company Inc → Buffalo Crushed Stone Company Inc; 2000-08-01 to 2010-12-31; source msha-controller-operator-history
- **operator_operates_mine:** New Enterprise Stone and Lime Co. Inc. → Franklinville Sand and Gravel; 2011-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** New Enterprise Stone & Lime Company Inc → New Enterprise Stone and Lime Co. Inc.; 2011-01-01 to current/open; source msha-controller-operator-history