# Red Canyon Quarry

- **MSHA mine ID:** 0504136
- **Status:** Active
- **Type / commodity:** Surface / Crushed, Broken Stone NEC
- **Location:** Fremont, CO
- **Operator:** Martin Marietta Materials Inc.
- **Controller:** Martin Marietta Materials Inc
- **Public source rows linked:** 2,068
- **Source coverage:** 15 / 20
- **Generated:** 2026-10-13T11:26:59.401Z

## Current entity hierarchy

**Martin Marietta Materials Inc (M00174) → Martin Marietta Materials Inc. (L16197) → Red Canyon Quarry (0504136)**

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

## Controller and operator valid-time history

- **Clinton A  Williams → C & C Sand Company Inc:** 1986-02-01 through 1991-12-06; derived from co-tenure at mine 0504136; source `msha-controller-operator-history`.
- **Stephen  Schnurr → Rocky Mountain Materials & Asphalt Inc:** 1991-12-07 through 2016-03-17; derived from co-tenure at mine 0504136; source `msha-controller-operator-history`.
- **Martin Marietta Materials Inc → Martin Marietta Materials Inc.:** 2016-03-18 through current/open; derived from co-tenure at mine 0504136; source `msha-controller-operator-history`.

- History rows: 3
- Typed edges: 9
- 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 — 0 since 2021:** Accidents and injuries 2 historical accident/injury rows; 0 coded fatalities and 0 lost days across the published record.
2. **COMPLIANCE — 29 since 2021:** Violations and penalties 141 violation rows across the full record; 24 carry an S&S flag and $50,127 appears in current assessed amounts.
3. **HEALTH — 37 samples:** Occupational health samples 37 personal. 2 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 8K employee hours and 13 summed average employees across reported subunits in the latest published quarter.
5. **LEGAL — 20 linked rows:** Contests, conferences and decisions 5 contested-violation rows, 7 civil-penalty docket/decision rows, and 8 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 — 14 since 2021:** Inspections 63 inspection events and 1K 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 56.4201 — Inspection.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-K/part-56/subpart-C/section-56.4201
- **30 CFR 56.14205 — Machinery, equipment, and tools.** (2 retained recent rows) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-K/part-56/subpart-M/section-56.14205
- **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 56.4101 — Warning signs.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-K/part-56/subpart-C/section-56.4101
- **30 CFR 56.9300 — Berms or guardrails.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-K/part-56/subpart-H/section-56.9300
- **30 CFR 56.16005 — Securing gas cylinders.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-K/part-56/subpart-O/section-56.16005
- **30 CFR 56.14132 — Horns and backup alarms.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-K/part-56/subpart-M/section-56.14132
- **30 CFR 56.12023 — Guarding electrical connections and resistor grids.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-K/part-56/subpart-K/section-56.12023
- **30 CFR 56.15005 — Safety belts and lines.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-K/part-56/subpart-N/section-56.15005
- **30 CFR 56.12004 — Electrical conductors.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-K/part-56/subpart-K/section-56.12004

## Source coverage

- **Accident, Injuries, and Illnesses:** 2 rows; 2002-11-20 through 2016-12-29; source ID `msha-accidents`
- **Addresses of Record:** 1 rows; 2013-11-19 through 2013-11-19; source ID `msha-addresses`
- **Assessed Violations:** 138 rows; 2000-04-26 through 2026-06-09; source ID `msha-assessed-violations`
- **Civil Penalty Dockets and Decisions:** 7 rows; 2004-05-06 through 2024-08-27; source ID `msha-civil-penalty-dockets-decisions`
- **Conferences:** 8 rows; 2006-01-09 through 2006-01-09; source ID `msha-conferences`
- **Contested Violations:** 5 rows; 2016-07-20 through 2023-11-07; source ID `msha-contested-violations`
- **Contractor Employment and Production — Quarterly:** 1,117 rows; unknown through unknown; source ID `msha-contractor-production-quarterly`
- **Contractor Employment and Production — Yearly:** 294 rows; unknown through unknown; source ID `msha-contractor-production-yearly`
- **Controller and Operator History:** 3 rows; 1986-02-01 through 2016-03-18; source ID `msha-controller-operator-history`
- **Inspections:** 63 rows; 2000-04-26 through 2026-06-08; source ID `msha-inspections`
- **Mine Employment and Production — Quarterly:** 201 rows; unknown through unknown; source ID `msha-mine-production-quarterly`
- **Mine Employment and Production — Yearly:** 50 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:** 37 rows; 2006-12-06 through 2024-05-01; source ID `msha-personal-health-samples`
- **Violations:** 141 rows; 2000-04-26 through 2026-06-09; 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/red-canyon-quarry-0504136`
- JSON: `/api/v1/mines/red-canyon-quarry-0504136`
- Silica records, units, sample status and quarterly means: `/api/v1/mines/0504136/silica` (snapshot year by default; `?year=all` for history; `&format=csv` for all matching rows)
- Relationship JSON: `/api/v1/mines/0504136/relationships`
- MCP resource: `mine://0504136/assessment`
- Complete Title 30 corpus: `/data/title30-sections.json`