# G3 Enterprises Byron Plant

- **MSHA mine ID:** 0401949
- **Status:** Active
- **Type / commodity:** Surface / Construction Sand and Gravel
- **Location:** Contra Costa, CA
- **Operator:** G3 Enterprises, Inc.
- **Controller:** Tom  Cook
- **Public source rows linked:** 1,195
- **Source coverage:** 15 / 20
- **Generated:** 2026-10-17T06:17:15.228Z

## Current entity hierarchy

**Tom  Cook (0101351) → G3 Enterprises, Inc. (0119333) → G3 Enterprises Byron Plant (0401949)**

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

## Controller and operator valid-time history

- **Sherman County - KS → Wedron Silica Division:** 1950-01-01 through 1979-04-30; derived from co-tenure at mine 0401949; source `msha-controller-operator-history`.
- **Twentieth Century Fox → Wedron Silica Company:** 1979-05-01 through 1979-09-11; derived from co-tenure at mine 0401949; source `msha-controller-operator-history`.
- **Martin Marietta Materials Inc → Martin Marietta Aggregates:** 1979-09-12 through 1983-10-13; derived from co-tenure at mine 0401949; source `msha-controller-operator-history`.
- **S C R-Sibelco Nv et al → Unimin Corporation:** 1983-10-14 through 2011-08-25; derived from co-tenure at mine 0401949; source `msha-controller-operator-history`.
- **Tom  Cook et al → G3 Enterprises, Inc.:** 2011-08-26 through current/open; derived from co-tenure at mine 0401949; source `msha-controller-operator-history`.
- **Covia Holdings LLC → Unimin Corporation:** 2021-01-01 through 2011-08-25; derived from co-tenure at mine 0401949; source `msha-controller-operator-history`.

- History rows: 6
- Typed edges: 17
- 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 — 5 since 2021:** Accidents and injuries 17 historical accident/injury rows; 0 coded fatalities and 695 lost days across the published record.
2. **COMPLIANCE — 55 since 2021:** Violations and penalties 261 violation rows across the full record; 60 carry an S&S flag and $90,364 appears in current assessed amounts.
3. **HEALTH — 34 samples:** Occupational health samples 34 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 10K employee hours and 18 summed average employees across reported subunits in the latest published quarter.
5. **LEGAL — 26 linked rows:** Contests, conferences and decisions 8 contested-violation rows, 8 civil-penalty docket/decision rows, and 10 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 — 23 since 2021:** Inspections 81 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 56.14112 — Construction and maintenance of guards.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-K/part-56/subpart-M/section-56.14112
- **30 CFR 56.20003 — Housekeeping.** (2 retained recent rows) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-K/part-56/subpart-S/section-56.20003
- **30 CFR 46.7 — New task training.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-H/part-46/section-46.7
- **30 CFR 56.15001 — First-aid materials.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-K/part-56/subpart-N/section-56.15001
- **30 CFR 56.11002 — Handrails and toeboards.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-K/part-56/subpart-J/section-56.11002
- **30 CFR 56.12032 — Inspection and cover plates.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-K/part-56/subpart-K/section-56.12032
- **30 CFR 56.14109 — Unguarded conveyors with adjacent travelways.** (2 retained recent rows) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-K/part-56/subpart-M/section-56.14109
- **30 CFR 56.11001 — Safe access.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-K/part-56/subpart-J/section-56.11001
- **30 CFR 56.14107 — Moving machine parts.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-K/part-56/subpart-M/section-56.14107
- **30 CFR 56.14101 — Brakes.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-K/part-56/subpart-M/section-56.14101

## Source coverage

- **Accident, Injuries, and Illnesses:** 17 rows; 2002-04-05 through 2026-02-27; source ID `msha-accidents`
- **Addresses of Record:** 1 rows; 1974-09-17 through 1974-09-17; source ID `msha-addresses`
- **Assessed Violations:** 259 rows; 2000-07-18 through 2026-08-20; source ID `msha-assessed-violations`
- **Civil Penalty Dockets and Decisions:** 8 rows; 2011-06-07 through 2017-12-13; source ID `msha-civil-penalty-dockets-decisions`
- **Conferences:** 10 rows; 2003-12-29 through 2012-06-15; source ID `msha-conferences`
- **Contested Violations:** 8 rows; 2009-06-17 through 2017-05-25; source ID `msha-contested-violations`
- **Contractor Employment and Production — Quarterly:** 368 rows; unknown through unknown; source ID `msha-contractor-production-quarterly`
- **Contractor Employment and Production — Yearly:** 67 rows; unknown through unknown; source ID `msha-contractor-production-yearly`
- **Controller and Operator History:** 6 rows; 1950-01-01 through 2011-08-26; source ID `msha-controller-operator-history`
- **Inspections:** 81 rows; 2000-07-18 through 2026-08-20; 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:** 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:** 34 rows; 2001-03-14 through 2025-10-21; source ID `msha-personal-health-samples`
- **Violations:** 261 rows; 2000-07-18 through 2026-08-20; 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/g3-enterprises-byron-plant-0401949`
- JSON: `/api/v1/mines/g3-enterprises-byron-plant-0401949`
- Silica records, units, sample status and quarterly means: `/api/v1/mines/0401949/silica` (snapshot year by default; `?year=all` for history; `&format=csv` for all matching rows)
- Relationship JSON: `/api/v1/mines/0401949/relationships`
- MCP resource: `mine://0401949/assessment`
- Complete Title 30 corpus: `/data/title30-sections.json`