# Relationship history for MSHA mine 0700101

Current hierarchy: **Ward William C-George H Brittingham → Contractors Sand & Gravel Company → Mount Pleasant Pit**

- 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:** Ward William C-George H Brittingham Et Al → Mount Pleasant Pit; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Contractors Sand & Gravel Company → Mount Pleasant Pit; 1986-11-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Ward William C-George H Brittingham Et Al → Contractors Sand & Gravel Company; 1986-11-01 to current/open; source msha-controller-operator-history