# Relationship history for MSHA mine 0201047

Current hierarchy: **ONEOK Partners L P → Black Mesa Pipeline Operations LLC → Kayenta Preparation Plant**

- 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:** Black Mesa Pipeline Inc → Kayenta Preparation Plant; 1950-01-01 to 1986-09-29; source msha-controller-operator-history
- **controller_controls_mine:** Southern Pacific Pipe Lines Inc → Kayenta Preparation Plant; 1950-01-01 to 1986-09-29; source msha-controller-operator-history
- **controller_controls_operator:** Southern Pacific Pipe Lines Inc → Black Mesa Pipeline Inc; 1950-01-01 to 1986-09-29; source msha-controller-operator-history
- **operator_operates_mine:** Black Mesa Pipeline Inc → Kayenta Preparation Plant; 1986-09-30 to 1988-05-16; source msha-controller-operator-history
- **controller_controls_mine:** Santa Fe Southern Pacific Corp → Kayenta Preparation Plant; 1986-09-30 to 1988-05-16; source msha-controller-operator-history
- **controller_controls_operator:** Santa Fe Southern Pacific Corp → Black Mesa Pipeline Inc; 1986-09-30 to 1988-05-16; source msha-controller-operator-history
- **operator_operates_mine:** Black Mesa Pipeline Inc → Kayenta Preparation Plant; 1988-05-17 to 1996-08-28; source msha-controller-operator-history
- **controller_controls_mine:** Prudential Insurance Co Of America et al → Kayenta Preparation Plant; 1988-05-17 to 1996-08-28; source msha-controller-operator-history
- **controller_controls_operator:** Prudential Insurance Co Of America et al → Black Mesa Pipeline Inc; 1988-05-17 to 1996-08-28; source msha-controller-operator-history
- **operator_operates_mine:** Black Mesa Pipeline Operations LLC → Kayenta Preparation Plant; 1996-08-29 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Northern Border Partners LP → Kayenta Preparation Plant; 1996-08-29 to 2006-11-30; source msha-controller-operator-history
- **controller_controls_operator:** Northern Border Partners LP → Black Mesa Pipeline Operations LLC; 1996-08-29 to 2006-11-30; source msha-controller-operator-history
- **controller_controls_mine:** ONEOK Partners L P → Kayenta Preparation Plant; 2006-12-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** ONEOK Partners L P → Black Mesa Pipeline Operations LLC; 2006-12-01 to current/open; source msha-controller-operator-history