# Seminoe II Mine

- **MSHA mine ID:** 4800828
- **Status:** Abandoned
- **Type / commodity:** Facility / Coal (Bituminous)
- **Location:** Carbon, WY
- **Operator:** Arch Of Wyoming LLC
- **Controller:** Arch Resources Inc
- **Public source rows linked:** 1,028
- **Source coverage:** 17 / 20
- **Generated:** 2026-10-17T06:17:15.228Z

## Current entity hierarchy

**Arch Resources Inc (C15561) → Arch Of Wyoming LLC (P17880) → Seminoe II Mine (4800828)**

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

## Controller and operator valid-time history

- **Ashland Inc et al → Arch Of Wyoming LLC:** 1950-01-01 through 2006-04-04; derived from co-tenure at mine 4800828; source `msha-controller-operator-history`.
- **Arch Resources Inc → Arch Of Wyoming LLC:** 2006-04-05 through current/open; derived from co-tenure at mine 4800828; source `msha-controller-operator-history`.

- History rows: 2
- Typed edges: 5
- 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 — 0 since 2021:** Accidents and injuries 3 historical accident/injury rows; 0 coded fatalities and 134 lost days across the published record.
2. **COMPLIANCE — 0 since 2021:** Violations and penalties 106 violation rows across the full record; 25 carry an S&S flag and $16,941 appears in current assessed amounts.
3. **HEALTH — 206 samples:** Occupational health samples 116 coal dust; 17 coal quartz; 73 noise. 0 personal-sample rows have a published C/E ratio above 1; 3 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 — 67K tons:** Quarterly production and employment 10K employee hours and 21 summed average employees across reported subunits in the latest published quarter.
5. **LEGAL — 14 linked rows:** Contests, conferences and decisions 5 contested-violation rows, 8 civil-penalty docket/decision rows, and 1 conference records linked by issuance number.
6. **CONTRACTORS — 1 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 — 0 since 2021:** Inspections 62 inspection events and 2K 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 77.701 — Grounding metallic frames, casings, and other enclosures of electric equipment.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-O/part-77/subpart-H/section-77.701
- **30 CFR 48.29 — Records of training.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-H/part-48/subpart-B/section-48.29
- **30 CFR 77.1110 — Examination and maintenance of firefighting equipment.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-O/part-77/subpart-L/section-77.1110
- **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 77.1713 — Daily inspection of surface coal mine; certified person; reports of inspection.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-O/part-77/subpart-R/section-77.1713
- **30 CFR 77.1607 — Loading and haulage equipment; operation.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-O/part-77/subpart-Q/section-77.1607
- **30 CFR 77.502-2 — Electric equipment; frequency of examination and testing.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-O/part-77/subpart-F/section-77.502-2
- **30 CFR 77.412 — Compressed air systems.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-O/part-77/subpart-E/section-77.412
- **30 CFR 77.1606 — Loading and haulage equipment; inspection and maintenance.** (2 retained recent rows) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-O/part-77/subpart-Q/section-77.1606
- **30 CFR 77.205 — Travelways at surface installations.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-O/part-77/subpart-C/section-77.205
- **30 CFR 77.400 — Mechanical equipment guards.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-O/part-77/subpart-E/section-77.400

## Source coverage

- **Accident, Injuries, and Illnesses:** 3 rows; 2001-08-06 through 2009-12-11; source ID `msha-accidents`
- **Addresses of Record:** 1 rows; 2015-05-18 through 2015-05-18; source ID `msha-addresses`
- **Assessed Violations:** 105 rows; 2000-03-22 through 2014-10-29; source ID `msha-assessed-violations`
- **Civil Penalty Dockets and Decisions:** 8 rows; 2004-07-10 through 2011-07-12; source ID `msha-civil-penalty-dockets-decisions`
- **Coal Dust Samples:** 116 rows; 2000-03-22 through 2012-06-26; source ID `msha-coal-dust-samples`
- **Conferences:** 1 rows; 2008-07-21 through 2008-07-21; source ID `msha-conferences`
- **Contested Violations:** 5 rows; 2003-12-03 through 2010-08-02; source ID `msha-contested-violations`
- **Contractor Employment and Production — Quarterly:** 416 rows; unknown through unknown; source ID `msha-contractor-production-quarterly`
- **Contractor Employment and Production — Yearly:** 66 rows; unknown through unknown; source ID `msha-contractor-production-yearly`
- **Controller and Operator History:** 2 rows; 1950-01-01 through 1950-01-01; source ID `msha-controller-operator-history`
- **Inspections:** 62 rows; 2000-03-07 through 2014-11-13; source ID `msha-inspections`
- **Mine Employment and Production — Quarterly:** 21 rows; unknown through unknown; source ID `msha-mine-production-quarterly`
- **Mine Employment and Production — Yearly:** 25 rows; unknown through unknown; source ID `msha-mine-production-yearly`
- **Mines:** 1 rows; unknown through unknown; source ID `msha-mines`
- **Noise Samples:** 73 rows; 2001-07-17 through 2013-11-13; source ID `msha-noise-samples`
- **Quartz Samples — Coal:** 17 rows; 2000-06-22 through 2011-09-01; source ID `msha-quartz-samples`
- **Violations:** 106 rows; 2000-03-22 through 2014-10-29; 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/seminoe-ii-mine-4800828`
- JSON: `/api/v1/mines/seminoe-ii-mine-4800828`
- Silica records, units, sample status and quarterly means: `/api/v1/mines/4800828/silica` (snapshot year by default; `?year=all` for history; `&format=csv` for all matching rows)
- Relationship JSON: `/api/v1/mines/4800828/relationships`
- MCP resource: `mine://4800828/assessment`
- Complete Title 30 corpus: `/data/title30-sections.json`