# Mt Pass Mine & Mill

- **MSHA mine ID:** 0402542
- **Status:** Active
- **Type / commodity:** Surface / Rare Earths Ore
- **Location:** San Bernardino, CA
- **Operator:** MP Mine Operations, LLC.
- **Controller:** MP Materials Corporation
- **Public source rows linked:** 13,729
- **Source coverage:** 16 / 20
- **Generated:** 2026-10-13T11:26:59.401Z

## Current entity hierarchy

**MP Materials Corporation (0159521) → MP Mine Operations, LLC. (0154633) → Mt Pass Mine & Mill (0402542)**

Current identity source: `msha-mines`. This is a current snapshot, not a historical claim.

## Controller and operator valid-time history

- **Unocal Corp → Molycorp Inc:** 1950-01-01 through 2005-11-29; derived from co-tenure at mine 0402542; source `msha-controller-operator-history`.
- **Chevron Corporation → Molycorp Inc:** 2005-11-30 through 2008-04-01; derived from co-tenure at mine 0402542; source `msha-controller-operator-history`.
- **Chevron Corporation → Chevron Mining Inc:** 2008-04-02 through 2008-11-06; derived from co-tenure at mine 0402542; source `msha-controller-operator-history`.
- **Traxys North America LLC et al → Molycorp Minerals:** 2008-11-07 through 2010-07-28; derived from co-tenure at mine 0402542; source `msha-controller-operator-history`.
- **Resource Capital Funds et al → Molycorp Minerals:** 2008-11-07 through 2010-07-28; derived from co-tenure at mine 0402542; source `msha-controller-operator-history`.
- **Molycorp Inc → Molycorp Minerals:** 2010-07-29 through 2017-12-10; derived from co-tenure at mine 0402542; source `msha-controller-operator-history`.
- **Saratoga Park Ltd et al → MP Mine Operations, LLC.:** 2017-12-11 through 2020-11-16; derived from co-tenure at mine 0402542; source `msha-controller-operator-history`.
- **JHL Capital Group Holdings Two LLC et al → MP Mine Operations, LLC.:** 2017-12-11 through 2020-11-16; derived from co-tenure at mine 0402542; source `msha-controller-operator-history`.
- **MP Materials Corporation → MP Mine Operations, LLC.:** 2020-11-17 through current/open; derived from co-tenure at mine 0402542; source `msha-controller-operator-history`.

- History rows: 9
- Typed edges: 20
- Interval anomalies: 0
- Valid-time bounds: inclusive; date granularity; null end means open-ended in the upstream history row; not independent proof of present control.
- Transaction-time observation: 2026-10-13T11:19:05.459773+00:00.

## Assessment signals

1. **SAFETY — 72 since 2021:** Accidents and injuries 213 historical accident/injury rows; 0 coded fatalities and 780 lost days across the published record.
2. **COMPLIANCE — 272 since 2021:** Violations and penalties 1,089 violation rows across the full record; 219 carry an S&S flag and $618,091 appears in current assessed amounts.
3. **HEALTH — 89 samples:** Occupational health samples 87 personal; 2 area. 0 personal-sample rows have a published C/E ratio above 1; 0 noise rows have an action-level or PEL dose above 100%. These are separate measures, not a silica exceedance count. Silica results and sample status are shown separately.
4. **PRODUCTION — 0 tons:** Quarterly production and employment 409K employee hours and 737 summed average employees across reported subunits in the latest published quarter.
5. **LEGAL — 467 linked rows:** Contests, conferences and decisions 204 contested-violation rows, 206 civil-penalty docket/decision rows, and 57 conference records linked by issuance number.
6. **CONTRACTORS — 74 linked entities:** Contractors Contractors are linked through this mine’s violation or accident records. Their production and hours cover all their operations, so they are not included in this mine’s totals.
7. **INSPECTIONS — 76 since 2021:** Inspections 208 inspection events and 7K published inspection hours across the historical record.

## EIA annual operating context

No matched record in the 2024 EIA coal-public workbook. This may be inapplicable for a non-coal operation.

## Recent Title 30 crosswalk

Snapshot current through 2026-08-19.

- **30 CFR 56.11001 — Safe access.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-K/part-56/subpart-J/section-56.11001
- **30 CFR 50.20-1 — General instructions for completing MSHA Form 7000-1.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-I/part-50/subpart-C/section-50.20-1
- **30 CFR 56.12028 — Testing grounding systems.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-K/part-56/subpart-K/section-56.12028
- **30 CFR 56.23003 — Requirements for written safety program.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-K/part-56/subpart-T/section-56.23003
- **30 CFR 56.18002 — Examination of working places.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-K/part-56/subpart-Q/section-56.18002
- **30 CFR 56.12019 — Access to stationary electrical equipment or switchgear.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-K/part-56/subpart-K/section-56.12019
- **30 CFR 56.14205 — Machinery, equipment, and tools.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-K/part-56/subpart-M/section-56.14205
- **30 CFR 56.20003 — Housekeeping.** (2 retained recent rows) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-K/part-56/subpart-S/section-56.20003
- **30 CFR 56.14107 — Moving machine parts.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-K/part-56/subpart-M/section-56.14107
- **30 CFR 56.12002 — Controls and switches.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-K/part-56/subpart-K/section-56.12002
- **30 CFR 56.15006 — Protective equipment and clothing for hazards and irritants.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-K/part-56/subpart-N/section-56.15006

## Source coverage

- **Accident, Injuries, and Illnesses:** 213 rows; 2000-02-27 through 2026-09-11; source ID `msha-accidents`
- **Addresses of Record:** 1 rows; 2017-12-13 through 2017-12-13; source ID `msha-addresses`
- **Metal and Nonmetal Area Samples:** 2 rows; 2009-02-21 through 2009-02-21; source ID `msha-area-samples`
- **Assessed Violations:** 1,079 rows; 2000-02-09 through 2026-08-17; source ID `msha-assessed-violations`
- **Civil Penalty Dockets and Decisions:** 206 rows; 2011-08-17 through 2025-10-02; source ID `msha-civil-penalty-dockets-decisions`
- **Conferences:** 57 rows; 2012-06-01 through 2024-01-26; source ID `msha-conferences`
- **Contested Violations:** 204 rows; 2010-11-08 through 2025-03-06; source ID `msha-contested-violations`
- **Contractor Employment and Production — Quarterly:** 8,478 rows; unknown through unknown; source ID `msha-contractor-production-quarterly`
- **Contractor Employment and Production — Yearly:** 1,725 rows; unknown through unknown; source ID `msha-contractor-production-yearly`
- **Controller and Operator History:** 9 rows; 1950-01-01 through 2017-12-11; source ID `msha-controller-operator-history`
- **Inspections:** 208 rows; 2000-02-08 through 2026-08-27; source ID `msha-inspections`
- **Mine Employment and Production — Quarterly:** 293 rows; unknown through unknown; source ID `msha-mine-production-quarterly`
- **Mine Employment and Production — Yearly:** 77 rows; unknown through unknown; source ID `msha-mine-production-yearly`
- **Mines:** 1 rows; unknown through unknown; source ID `msha-mines`
- **Metal and Nonmetal Personal Health Samples:** 87 rows; 2001-12-12 through 2026-07-21; source ID `msha-personal-health-samples`
- **Violations:** 1,089 rows; 2000-02-09 through 2026-08-17; source ID `msha-violations`

## Caveats

- This is public-record decision support, not legal advice or an official MSHA record.
- Missing data can indicate no event, publication delay, an unresolved identity, or inapplicability.
- Contractor production data is entity-level and is not attributed to this mine.

## Alternate representations

- HTML: `/mines/mt-pass-mine-mill-0402542`
- JSON: `/api/v1/mines/mt-pass-mine-mill-0402542`
- Silica records, units, sample status and quarterly means: `/api/v1/mines/0402542/silica` (snapshot year by default; `?year=all` for history; `&format=csv` for all matching rows)
- Relationship JSON: `/api/v1/mines/0402542/relationships`
- MCP resource: `mine://0402542/assessment`
- Complete Title 30 corpus: `/data/title30-sections.json`