# Arcosa Boulder Plant #1604

- **MSHA mine ID:** 0504415
- **Status:** Intermittent
- **Type / commodity:** Surface / Common Shale
- **Location:** Jefferson, CO
- **Operator:** ARCOSA LWB, LLC
- **Controller:** Arcosa, Inc
- **Public source rows linked:** 1,925
- **Source coverage:** 15 / 20
- **Generated:** 2026-10-17T06:17:15.228Z

## Current entity hierarchy

**Arcosa, Inc (0144281) → ARCOSA LWB, LLC (0134299) → Arcosa Boulder Plant #1604 (0504415)**

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

## Controller and operator valid-time history

- **Inco Ltd → Western Aggregates:** 1989-12-01 through 1997-11-24; derived from co-tenure at mine 0504415; source `msha-controller-operator-history`.
- **Texas Industries Inc → Texas Industries:** 1997-11-25 through 2005-03-14; derived from co-tenure at mine 0504415; source `msha-controller-operator-history`.
- **Texas Industries Inc → TXI Operations LP:** 2005-03-15 through 2013-03-22; derived from co-tenure at mine 0504415; source `msha-controller-operator-history`.
- **Trinity Industries Inc → ARCOSA LWB, LLC:** 2013-03-23 through 2018-10-31; derived from co-tenure at mine 0504415; source `msha-controller-operator-history`.
- **Martin Marietta Materials Inc → TXI Operations LP:** 2014-07-02 through 2013-03-22; derived from co-tenure at mine 0504415; source `msha-controller-operator-history`.
- **Arcosa, Inc → ARCOSA LWB, LLC:** 2018-11-01 through current/open; derived from co-tenure at mine 0504415; source `msha-controller-operator-history`.

- History rows: 6
- Typed edges: 16
- Interval anomalies: 1
- 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 — 11 since 2021:** Accidents and injuries 38 historical accident/injury rows; 0 coded fatalities and 590 lost days across the published record.
2. **COMPLIANCE — 222 since 2021:** Violations and penalties 400 violation rows across the full record; 82 carry an S&S flag and $275,121 appears in current assessed amounts.
3. **HEALTH — 55 samples:** Occupational health samples 55 personal. 4 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 22K employee hours and 42 summed average employees across reported subunits in the latest published quarter.
5. **LEGAL — 37 linked rows:** Contests, conferences and decisions 18 contested-violation rows, 18 civil-penalty docket/decision rows, and 1 conference records linked by issuance number.
6. **CONTRACTORS — 7 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 — 27 since 2021:** Inspections 82 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 46.9 — Records of training.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-H/part-46/section-46.9
- **30 CFR 56.14100 — Safety defects; examination, correction and records.** (2 retained recent rows) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-K/part-56/subpart-M/section-56.14100
- **30 CFR 56.13011 — Air receiver tanks.** (2 retained recent rows) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-K/part-56/subpart-L/section-56.13011
- **30 CFR 56.4130 — Electric substations and liquid storage facilities.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-K/part-56/subpart-C/section-56.4130
- **30 CFR 56.20003 — Housekeeping.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-K/part-56/subpart-S/section-56.20003
- **30 CFR 56.12025 — Grounding circuit enclosures.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-K/part-56/subpart-K/section-56.12025
- **30 CFR 56.14107 — Moving machine parts.** (2 retained recent rows) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-K/part-56/subpart-M/section-56.14107
- **30 CFR 56.12030 — Correction of dangerous conditions.** (2 retained recent rows) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-K/part-56/subpart-K/section-56.12030

## Source coverage

- **Accident, Injuries, and Illnesses:** 38 rows; 2001-04-12 through 2025-02-16; source ID `msha-accidents`
- **Addresses of Record:** 1 rows; 2026-07-22 through 2026-07-22; source ID `msha-addresses`
- **Assessed Violations:** 398 rows; 2000-03-07 through 2025-10-30; source ID `msha-assessed-violations`
- **Civil Penalty Dockets and Decisions:** 18 rows; 2010-05-20 through 2026-07-10; source ID `msha-civil-penalty-dockets-decisions`
- **Conferences:** 1 rows; 2022-09-06 through 2022-09-06; source ID `msha-conferences`
- **Contested Violations:** 18 rows; 2009-04-08 through 2025-06-23; source ID `msha-contested-violations`
- **Contractor Employment and Production — Quarterly:** 662 rows; unknown through unknown; source ID `msha-contractor-production-quarterly`
- **Contractor Employment and Production — Yearly:** 167 rows; unknown through unknown; source ID `msha-contractor-production-yearly`
- **Controller and Operator History:** 6 rows; 1989-12-01 through 2013-03-23; source ID `msha-controller-operator-history`
- **Inspections:** 82 rows; 2000-03-06 through 2025-10-27; source ID `msha-inspections`
- **Mine Employment and Production — Quarterly:** 24 rows; unknown through unknown; source ID `msha-mine-production-quarterly`
- **Mine Employment and Production — Yearly:** 54 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:** 55 rows; 2000-08-01 through 2025-10-29; source ID `msha-personal-health-samples`
- **Violations:** 400 rows; 2000-03-07 through 2025-10-30; 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/arcosa-boulder-plant-1604-0504415`
- JSON: `/api/v1/mines/arcosa-boulder-plant-1604-0504415`
- Silica records, units, sample status and quarterly means: `/api/v1/mines/0504415/silica` (snapshot year by default; `?year=all` for history; `&format=csv` for all matching rows)
- Relationship JSON: `/api/v1/mines/0504415/relationships`
- MCP resource: `mine://0504415/assessment`
- Complete Title 30 corpus: `/data/title30-sections.json`