# Relationship history for MSHA mine 0402386

Current hierarchy: **Jemco LLC → Cal Sierra Development Inc → Dredge 17**

- 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:** Yuba Goldfields Inc → Dredge 17; 1950-01-01 to 1981-12-07; source msha-controller-operator-history
- **controller_controls_mine:** Yuba Natural Resources Inc → Dredge 17; 1950-01-01 to 1981-12-07; source msha-controller-operator-history
- **controller_controls_operator:** Yuba Natural Resources Inc → Yuba Goldfields Inc; 1950-01-01 to 1981-12-07; source msha-controller-operator-history
- **operator_operates_mine:** Yuba Placer Gold Company → Dredge 17; 1981-12-08 to 1992-12-17; source msha-controller-operator-history
- **controller_controls_mine:** Westgold Placer Inc & Yuba Westgold Inc → Dredge 17; 1981-12-08 to 1992-12-17; source msha-controller-operator-history
- **controller_controls_operator:** Westgold Placer Inc & Yuba Westgold Inc → Yuba Placer Gold Company; 1981-12-08 to 1992-12-17; source msha-controller-operator-history
- **operator_operates_mine:** Cal-Sierra Development Inc → Dredge 17; 1992-12-18 to 2001-03-31; source msha-controller-operator-history
- **controller_controls_mine:** Lowell  Robinson → Dredge 17; 1992-12-18 to 2001-03-31; source msha-controller-operator-history
- **controller_controls_operator:** Lowell  Robinson → Cal-Sierra Development Inc; 1992-12-18 to 2001-03-31; source msha-controller-operator-history
- **operator_operates_mine:** Cal Sierra Development Inc → Dredge 17; 2001-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Jemco LLC → Dredge 17; 2001-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Jemco LLC → Cal Sierra Development Inc; 2001-04-01 to current/open; source msha-controller-operator-history