# Relationship history for MSHA mine 3304371

Current hierarchy: **Mary C Gerrard; Sharon L Mills; Robert E Small; Jeffrey T Small → Small's Sand & Gravel Inc. → PLANT #2**

- 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:** Michael W  Small et al → PLANT #2; 1950-01-01 to 2023-07-27; source msha-controller-operator-history
- **operator_operates_mine:** Small'S Sand & Gravel Inc → PLANT #2; 1996-05-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Michael W  Small et al → Small'S Sand & Gravel Inc; 1996-05-01 to 2023-07-27; source msha-controller-operator-history
- **controller_controls_mine:** Mary C Gerrard et al → PLANT #2; 2023-07-28 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Mary C Gerrard et al → Small'S Sand & Gravel Inc; 2023-07-28 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Robert E Small et al → Small'S Sand & Gravel Inc; 2023-07-28 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Jeffrey T Small et al → Small'S Sand & Gravel Inc; 2023-07-28 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Sharon L Mills et al → Small'S Sand & Gravel Inc; 2023-07-28 to current/open; source msha-controller-operator-history