# North Austin Quarry

- **MSHA mine ID:** 4104380
- **Status:** Active
- **Type / commodity:** Surface / Construction Sand and Gravel
- **Location:** Williamson, TX
- **Operator:** Martin Marietta Materials Southwest LLC
- **Controller:** Martin Marietta Materials Inc
- **Public source rows linked:** 1,077
- **Source coverage:** 15 / 20
- **Generated:** 2026-10-13T11:26:59.401Z

## Current entity hierarchy

**Martin Marietta Materials Inc (M00174) → Martin Marietta Materials Southwest LLC (0084984) → North Austin Quarry (4104380)**

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

## Controller and operator valid-time history

- **Blake A  Kuhlman → American Aggregates:** 2002-08-13 through 2013-04-01; derived from co-tenure at mine 4104380; source `msha-controller-operator-history`.
- **Group Investment Holdings Inc → Texas Limestone Materials, LLC:** 2013-04-02 through 2015-08-16; derived from co-tenure at mine 4104380; source `msha-controller-operator-history`.
- **Curtis L  Griffin → CC Aggregates LLC:** 2015-08-17 through 2021-10-21; derived from co-tenure at mine 4104380; source `msha-controller-operator-history`.
- **Martin Marietta Materials Inc → Martin Marietta Materials Southwest LLC:** 2021-10-22 through current/open; derived from co-tenure at mine 4104380; source `msha-controller-operator-history`.

- History rows: 4
- Typed edges: 12
- 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 — 1 since 2021:** Accidents and injuries 2 historical accident/injury rows; 0 coded fatalities and 206 lost days across the published record.
2. **COMPLIANCE — 20 since 2021:** Violations and penalties 205 violation rows across the full record; 48 carry an S&S flag and $60,192 appears in current assessed amounts.
3. **HEALTH — 18 samples:** Occupational health samples 18 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 608 employee hours and 2 summed average employees across reported subunits in the latest published quarter.
5. **LEGAL — 15 linked rows:** Contests, conferences and decisions 7 contested-violation rows, 7 civil-penalty docket/decision rows, and 1 conference records linked by issuance number.
6. **CONTRACTORS — 6 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 — 15 since 2021:** Inspections 70 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 56.13012 — Compressor air intakes.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-K/part-56/subpart-L/section-56.13012
- **30 CFR 50.20 — Preparation and submission of MSHA Report Form 7000-1—Mine Accident, Injury, and Illness Report.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-I/part-50/subpart-C/section-50.20
- **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 56.4402 — Safety can use.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-K/part-56/subpart-C/section-56.4402
- **30 CFR 56.4230 — Self-propelled equipment.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-K/part-56/subpart-C/section-56.4230
- **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 56.14132 — 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 56.12018 — Identification of power switches.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-K/part-56/subpart-K/section-56.12018
- **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
- **30 CFR 56.12020 — Protection of persons at switchgear.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-K/part-56/subpart-K/section-56.12020
- **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
- **30 CFR 50.30 — Preparation and submission of MSHA Form 7000-2—Quarterly Employment and Coal Production Report.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-I/part-50/subpart-D/section-50.30

## Source coverage

- **Accident, Injuries, and Illnesses:** 2 rows; 2017-08-30 through 2024-05-28; source ID `msha-accidents`
- **Addresses of Record:** 1 rows; 2014-04-01 through 2014-04-01; source ID `msha-addresses`
- **Assessed Violations:** 204 rows; 2004-01-14 through 2025-04-25; source ID `msha-assessed-violations`
- **Civil Penalty Dockets and Decisions:** 7 rows; 2015-08-20 through 2022-02-15; source ID `msha-civil-penalty-dockets-decisions`
- **Conferences:** 1 rows; 2026-09-29 through 2026-09-29; source ID `msha-conferences`
- **Contested Violations:** 7 rows; 2015-02-03 through 2021-05-04; source ID `msha-contested-violations`
- **Contractor Employment and Production — Quarterly:** 266 rows; unknown through unknown; source ID `msha-contractor-production-quarterly`
- **Contractor Employment and Production — Yearly:** 71 rows; unknown through unknown; source ID `msha-contractor-production-yearly`
- **Controller and Operator History:** 4 rows; 2002-08-13 through 2021-10-22; source ID `msha-controller-operator-history`
- **Inspections:** 70 rows; 2003-03-05 through 2026-04-14; source ID `msha-inspections`
- **Mine Employment and Production — Quarterly:** 176 rows; unknown through unknown; source ID `msha-mine-production-quarterly`
- **Mine Employment and Production — Yearly:** 44 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:** 18 rows; 2005-10-27 through 2022-06-02; source ID `msha-personal-health-samples`
- **Violations:** 205 rows; 2004-01-14 through 2026-04-14; 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/north-austin-quarry-4104380`
- JSON: `/api/v1/mines/north-austin-quarry-4104380`
- Silica records, units, sample status and quarterly means: `/api/v1/mines/4104380/silica` (snapshot year by default; `?year=all` for history; `&format=csv` for all matching rows)
- Relationship JSON: `/api/v1/mines/4104380/relationships`
- MCP resource: `mine://4104380/assessment`
- Complete Title 30 corpus: `/data/title30-sections.json`