# Colowyo Mine

- **MSHA mine ID:** 0502962
- **Status:** NonProducing
- **Type / commodity:** Surface / Coal (Bituminous)
- **Location:** Moffat, CO
- **Operator:** Kiewit Mining Group Inc
- **Controller:** Kiewit Peter Sons' Inc
- **Public source rows linked:** 9,564
- **Source coverage:** 17 / 20
- **Generated:** 2026-10-13T11:26:59.401Z

## Current entity hierarchy

**Kiewit Peter Sons' Inc (C02111) → Kiewit Mining Group Inc (0053919) → Colowyo Mine (0502962)**

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

## Controller and operator valid-time history

- **W R Grace & Company → Colowyo Coal Company L P:** 1976-10-01 through 1994-12-05; derived from co-tenure at mine 0502962; source `msha-controller-operator-history`.
- **RTZ-CRA Group → Colowyo Coal Company L P:** 1994-12-06 through 2011-11-30; derived from co-tenure at mine 0502962; source `msha-controller-operator-history`.
- **Tri-State Generation & Transmission Assn Inc et al → Colowyo Coal Company L P:** 2011-12-01 through 2016-05-10; derived from co-tenure at mine 0502962; source `msha-controller-operator-history`.
- **Western Fuels Assoc Inc et al → Colowyo Coal Company L P:** 2011-12-01 through 2016-05-10; derived from co-tenure at mine 0502962; source `msha-controller-operator-history`.
- **Tri-State Generation and Transmission Assn Inc → Colowyo Coal Company L P:** 2016-05-11 through 2026-01-04; derived from co-tenure at mine 0502962; source `msha-controller-operator-history`.
- **Kiewit Peter Sons' Inc → Kiewit Mining Group Inc:** 2026-01-05 through current/open; derived from co-tenure at mine 0502962; source `msha-controller-operator-history`.

- History rows: 6
- Typed edges: 14
- 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 — 28 since 2021:** Accidents and injuries 114 historical accident/injury rows; 1 coded fatalities and 2,580 lost days across the published record.
2. **COMPLIANCE — 30 since 2021:** Violations and penalties 671 violation rows across the full record; 130 carry an S&S flag and $448,768 appears in current assessed amounts.
3. **HEALTH — 920 samples:** Occupational health samples 623 coal dust; 60 coal quartz; 237 noise. 0 personal-sample rows have a published C/E ratio above 1; 8 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 79K employee hours and 152 summed average employees across reported subunits in the latest published quarter.
5. **LEGAL — 93 linked rows:** Contests, conferences and decisions 41 contested-violation rows, 42 civil-penalty docket/decision rows, and 10 conference records linked by issuance number.
6. **CONTRACTORS — 22 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 — 24 since 2021:** Inspections 147 inspection events and 12K published inspection hours across the historical record.

## EIA annual operating context

- **Reporting year:** 2024
- **Production:** 1,713,919 short tons
- **Labor hours:** 305,379
- **Average employees:** 184
- **Coal supply region:** Uinta Region
- **Union code:** Not published
- **Published rows under this MSHA ID:** 1

## Recent Title 30 crosswalk

Snapshot current through 2026-08-19.

- **30 CFR 77.1102 — Warning signs; smoking and open flame.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-O/part-77/subpart-L/section-77.1102
- **30 CFR 77.404 — Machinery and equipment; operation and maintenance.** (2 retained recent rows) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-O/part-77/subpart-E/section-77.404
- **30 CFR 77.1110 — Examination and maintenance of firefighting equipment.** (7 retained recent rows) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-O/part-77/subpart-L/section-77.1110
- **30 CFR 77.502 — Electric equipment; examination, testing, and maintenance.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-O/part-77/subpart-F/section-77.502
- **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

## Source coverage

- **Accident, Injuries, and Illnesses:** 114 rows; 2000-05-15 through 2026-09-12; source ID `msha-accidents`
- **Addresses of Record:** 1 rows; 2026-07-20 through 2026-07-20; source ID `msha-addresses`
- **Assessed Violations:** 664 rows; 2000-05-10 through 2026-08-05; source ID `msha-assessed-violations`
- **Civil Penalty Dockets and Decisions:** 42 rows; 2002-05-01 through 2022-01-14; source ID `msha-civil-penalty-dockets-decisions`
- **Coal Dust Samples:** 623 rows; 2000-01-05 through 2026-09-23; source ID `msha-coal-dust-samples`
- **Conferences:** 10 rows; 2001-05-15 through 2013-01-11; source ID `msha-conferences`
- **Contested Violations:** 41 rows; 2007-12-19 through 2021-06-03; source ID `msha-contested-violations`
- **Contractor Employment and Production — Quarterly:** 5,428 rows; unknown through unknown; source ID `msha-contractor-production-quarterly`
- **Contractor Employment and Production — Yearly:** 1,078 rows; unknown through unknown; source ID `msha-contractor-production-yearly`
- **Controller and Operator History:** 6 rows; 1976-10-01 through 2026-01-05; source ID `msha-controller-operator-history`
- **Inspections:** 147 rows; 2000-03-20 through 2026-10-08; source ID `msha-inspections`
- **Mine Employment and Production — Quarterly:** 360 rows; unknown through unknown; source ID `msha-mine-production-quarterly`
- **Mine Employment and Production — Yearly:** 81 rows; unknown through unknown; source ID `msha-mine-production-yearly`
- **Mines:** 1 rows; unknown through unknown; source ID `msha-mines`
- **Noise Samples:** 237 rows; 2000-04-03 through 2026-07-22; source ID `msha-noise-samples`
- **Quartz Samples — Coal:** 60 rows; 2000-03-21 through 2026-03-05; source ID `msha-quartz-samples`
- **Violations:** 671 rows; 2000-05-10 through 2026-08-05; 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/colowyo-mine-0502962`
- JSON: `/api/v1/mines/colowyo-mine-0502962`
- Silica records, units, sample status and quarterly means: `/api/v1/mines/0502962/silica` (snapshot year by default; `?year=all` for history; `&format=csv` for all matching rows)
- Relationship JSON: `/api/v1/mines/0502962/relationships`
- MCP resource: `mine://0502962/assessment`
- Complete Title 30 corpus: `/data/title30-sections.json`