# OSHOTO MINE

- **MSHA mine ID:** 4801376
- **Status:** Intermittent
- **Type / commodity:** Surface / Bentonite
- **Location:** Weston, WY
- **Operator:** Black Hills Bentonite
- **Controller:** BHB Limited Partnership; A&M Products
- **Public source rows linked:** 391
- **Source coverage:** 14 / 20
- **Generated:** 2026-10-17T06:17:15.228Z

## Current entity hierarchy

**BHB Limited Partnership; A&M Products (0167941) → Black Hills Bentonite (L09605) → OSHOTO MINE (4801376)**

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

## Controller and operator valid-time history

- **Asea Brown Boveri Ltd (ABB) → Benton Clay Company:** 1982-10-01 through 1984-06-14; derived from co-tenure at mine 4801376; source `msha-controller-operator-history`.
- **T A  Thorson → Kaycee Bentonite Corp:** 1984-06-15 through 1986-12-31; derived from co-tenure at mine 4801376; source `msha-controller-operator-history`.
- **Thomas A  Thorson et al → Black Hills Bentonite:** 1987-01-01 through 2020-06-30; derived from co-tenure at mine 4801376; source `msha-controller-operator-history`.
- **A&M Products et al → Black Hills Bentonite:** 2020-07-01 through current/open; derived from co-tenure at mine 4801376; source `msha-controller-operator-history`.
- **BHB Limited Partnership et al → Black Hills Bentonite:** 2020-07-01 through current/open; derived from co-tenure at mine 4801376; source `msha-controller-operator-history`.

- History rows: 5
- Typed edges: 12
- 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: 2026-10-17T05:35:58.500035+00:00.

## Assessment signals

1. **SAFETY — 1 since 2021:** Accidents and injuries 7 historical accident/injury rows; 0 coded fatalities and 310 lost days across the published record.
2. **COMPLIANCE — 26 since 2021:** Violations and penalties 70 violation rows across the full record; 8 carry an S&S flag and $11,411 appears in current assessed amounts.
3. **HEALTH — 21 samples:** Occupational health samples 21 personal. 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 2K employee hours and 2 summed average employees across reported subunits in the latest published quarter.
5. **LEGAL — 8 linked rows:** Contests, conferences and decisions 4 contested-violation rows, 4 civil-penalty docket/decision rows, and 0 conference records linked by issuance number.
6. **CONTRACTORS — 4 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 — 16 since 2021:** Inspections 66 inspection events and 886 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 56.14100 — Safety defects; examination, correction and records.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-K/part-56/subpart-M/section-56.14100
- **30 CFR 56.14132 — Horns and backup alarms.** (2 retained recent rows) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-K/part-56/subpart-M/section-56.14132
- **30 CFR 56.9315 — Dust control.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-K/part-56/subpart-H/section-56.9315
- **30 CFR 56.14130 — Roll-over protective structures (ROPS) and seat belts.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-K/part-56/subpart-M/section-56.14130
- **30 CFR 56.4402 — Safety can use.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-K/part-56/subpart-C/section-56.4402
- **30 CFR 47.41 — Requirement for container labels.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-H/part-47/subpart-E/section-47.41
- **30 CFR 46.12 — Responsibility for independent contractor training.** (3 retained recent rows) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-H/part-46/section-46.12
- **30 CFR 46.9 — Records of training.** (2 retained recent rows) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-H/part-46/section-46.9

## Source coverage

- **Accident, Injuries, and Illnesses:** 7 rows; 2003-03-10 through 2022-02-21; source ID `msha-accidents`
- **Addresses of Record:** 1 rows; 2021-05-13 through 2021-05-13; source ID `msha-addresses`
- **Assessed Violations:** 70 rows; 2006-01-10 through 2024-08-13; source ID `msha-assessed-violations`
- **Civil Penalty Dockets and Decisions:** 4 rows; 2017-09-14 through 2023-06-07; source ID `msha-civil-penalty-dockets-decisions`
- **Contested Violations:** 4 rows; 2017-02-02 through 2022-10-11; source ID `msha-contested-violations`
- **Contractor Employment and Production — Quarterly:** 88 rows; unknown through unknown; source ID `msha-contractor-production-quarterly`
- **Contractor Employment and Production — Yearly:** 17 rows; unknown through unknown; source ID `msha-contractor-production-yearly`
- **Controller and Operator History:** 5 rows; 1982-10-01 through 1987-01-01; source ID `msha-controller-operator-history`
- **Inspections:** 66 rows; 2001-04-24 through 2025-10-08; source ID `msha-inspections`
- **Mine Employment and Production — Quarterly:** 10 rows; unknown through unknown; source ID `msha-mine-production-quarterly`
- **Mine Employment and Production — Yearly:** 27 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:** 21 rows; 2006-07-12 through 2025-10-09; source ID `msha-personal-health-samples`
- **Violations:** 70 rows; 2006-01-10 through 2024-08-13; 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/oshoto-mine-4801376`
- JSON: `/api/v1/mines/oshoto-mine-4801376`
- Silica records, units, sample status and quarterly means: `/api/v1/mines/4801376/silica` (snapshot year by default; `?year=all` for history; `&format=csv` for all matching rows)
- Relationship JSON: `/api/v1/mines/4801376/relationships`
- MCP resource: `mine://4801376/assessment`
- Complete Title 30 corpus: `/data/title30-sections.json`