# Relationship history for MSHA mine 2601972

Current hierarchy: **Floyd A  Meldrum → Boulder Sand & Gravel Inc → BOOTLEG CANYON RES.**

- 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:** R L Contractor → BOOTLEG CANYON RES.; 1986-08-01 to 1988-06-12; source msha-controller-operator-history
- **controller_controls_mine:** Roland G  Langlois → BOOTLEG CANYON RES.; 1986-08-01 to 1988-06-12; source msha-controller-operator-history
- **controller_controls_operator:** Roland G  Langlois → R L Contractor; 1986-08-01 to 1988-06-12; source msha-controller-operator-history
- **operator_operates_mine:** Boulder Sand & Gravel Inc → BOOTLEG CANYON RES.; 1988-06-13 to 1997-04-21; source msha-controller-operator-history
- **controller_controls_mine:** Ben Keith  Pearce → BOOTLEG CANYON RES.; 1988-06-13 to 1997-04-21; source msha-controller-operator-history
- **controller_controls_operator:** Ben Keith  Pearce → Boulder Sand & Gravel Inc; 1988-06-13 to 1997-04-21; source msha-controller-operator-history
- **operator_operates_mine:** Boulder Sand & Gravel Inc → BOOTLEG CANYON RES.; 1997-04-22 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Judy  Jensen → BOOTLEG CANYON RES.; 1997-04-22 to 2011-12-22; source msha-controller-operator-history
- **controller_controls_operator:** Judy  Jensen → Boulder Sand & Gravel Inc; 1997-04-22 to 2011-12-22; source msha-controller-operator-history
- **controller_controls_mine:** Floyd A  Meldrum → BOOTLEG CANYON RES.; 2011-12-23 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Floyd A  Meldrum → Boulder Sand & Gravel Inc; 2011-12-23 to current/open; source msha-controller-operator-history