# Relationship history for MSHA mine 1101618

Current hierarchy: **Holley  Bailey; Charles  Adams → Prosser Construction Company → Prosser Construction Co.**

- 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

- **operator_operates_mine:** Hanfland Sand & Gravel Company → Prosser Construction Co.; 1950-01-01 to 1981-02-28; source msha-controller-operator-history
- **controller_controls_mine:** Maurice  Weishaar → Prosser Construction Co.; 1950-01-01 to 1981-02-28; source msha-controller-operator-history
- **controller_controls_operator:** Maurice  Weishaar → Hanfland Sand & Gravel Company; 1950-01-01 to 1981-02-28; source msha-controller-operator-history
- **operator_operates_mine:** G W Prosser Company → Prosser Construction Co.; 1981-03-01 to 1997-06-15; source msha-controller-operator-history
- **controller_controls_mine:** James H  Prosser → Prosser Construction Co.; 1981-03-01 to 1997-06-15; source msha-controller-operator-history
- **controller_controls_operator:** James H  Prosser → G W Prosser Company; 1981-03-01 to 1997-06-15; source msha-controller-operator-history
- **operator_operates_mine:** Prosser Construction Company → Prosser Construction Co.; 1997-06-16 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Holley  Bailey et al → Prosser Construction Co.; 1997-06-16 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Holley  Bailey et al → Prosser Construction Company; 1997-06-16 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Charles  Adams et al → Prosser Construction Company; 1997-06-16 to current/open; source msha-controller-operator-history