# Superior - Twin Oaks

- **MSHA mine ID:** 0405514
- **Status:** Active
- **Type / commodity:** Surface / Crushed, Broken Stone NEC
- **Location:** San Diego, CA
- **Operator:** Superior Ready Mix Concrete L.P.
- **Controller:** Vulcan Materials Company
- **Public source rows linked:** 767
- **Source coverage:** 14 / 20
- **Generated:** 2026-10-13T11:26:59.401Z

## Current entity hierarchy

**Vulcan Materials Company (0071891) → Superior Ready Mix Concrete L.P. (L10579) → Superior - Twin Oaks (0405514)**

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

## Controller and operator valid-time history

- **Jeff C  Halloran → Wyroc Inc:** 2002-02-14 through 2011-03-08; derived from co-tenure at mine 0405514; source `msha-controller-operator-history`.
- **J Brouwer Investments Inc Et Al → Superior Ready Mix Concrete L.P.:** 2011-03-09 through 2025-04-27; derived from co-tenure at mine 0405514; source `msha-controller-operator-history`.
- **Vulcan Materials Company → Superior Ready Mix Concrete L.P.:** 2025-04-28 through current/open; derived from co-tenure at mine 0405514; source `msha-controller-operator-history`.

- History rows: 3
- Typed edges: 8
- 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 — 4 since 2021:** Accidents and injuries 8 historical accident/injury rows; 0 coded fatalities and 303 lost days across the published record.
2. **COMPLIANCE — 31 since 2021:** Violations and penalties 194 violation rows across the full record; 59 carry an S&S flag and $65,552 appears in current assessed amounts.
3. **HEALTH — 27 samples:** Occupational health samples 27 personal. 3 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 7K employee hours and 16 summed average employees across reported subunits in the latest published quarter.
5. **LEGAL — 12 linked rows:** Contests, conferences and decisions 6 contested-violation rows, 6 civil-penalty docket/decision rows, and 0 conference records linked by issuance number.
6. **CONTRACTORS — 1 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 — 12 since 2021:** Inspections 69 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 56.12032 — Inspection and cover plates.** (2 retained recent rows) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-K/part-56/subpart-K/section-56.12032
- **30 CFR 56.12018 — Identification of power switches.** (2 retained recent rows) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-K/part-56/subpart-K/section-56.12018
- **30 CFR 56.20011 — Barricades and warning signs.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-K/part-56/subpart-S/section-56.20011
- **30 CFR 56.14112 — Construction and maintenance of guards.** (2 retained recent rows) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-K/part-56/subpart-M/section-56.14112
- **30 CFR 46.7 — New task training.** (2 retained recent rows) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-H/part-46/section-46.7
- **30 CFR 56.13015 — Inspection of compressed-air receivers and other unfired pressure vessels.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-K/part-56/subpart-L/section-56.13015
- **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 56.14110 — Flying or falling materials.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-K/part-56/subpart-M/section-56.14110

## Source coverage

- **Accident, Injuries, and Illnesses:** 8 rows; 2005-05-17 through 2025-04-25; source ID `msha-accidents`
- **Addresses of Record:** 1 rows; 2002-03-14 through 2002-03-14; source ID `msha-addresses`
- **Assessed Violations:** 190 rows; 2002-05-14 through 2025-06-25; source ID `msha-assessed-violations`
- **Civil Penalty Dockets and Decisions:** 6 rows; 2010-01-06 through 2011-04-12; source ID `msha-civil-penalty-dockets-decisions`
- **Contested Violations:** 6 rows; 2008-11-18 through 2008-11-18; source ID `msha-contested-violations`
- **Contractor Employment and Production — Quarterly:** 13 rows; unknown through unknown; source ID `msha-contractor-production-quarterly`
- **Contractor Employment and Production — Yearly:** 5 rows; unknown through unknown; source ID `msha-contractor-production-yearly`
- **Controller and Operator History:** 3 rows; 2002-02-14 through 2011-03-09; source ID `msha-controller-operator-history`
- **Inspections:** 69 rows; 2002-05-14 through 2026-05-18; source ID `msha-inspections`
- **Mine Employment and Production — Quarterly:** 194 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:** 27 rows; 2003-11-25 through 2025-01-23; source ID `msha-personal-health-samples`
- **Violations:** 194 rows; 2002-05-14 through 2025-06-25; 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/superior-twin-oaks-0405514`
- JSON: `/api/v1/mines/superior-twin-oaks-0405514`
- Silica records, units, sample status and quarterly means: `/api/v1/mines/0405514/silica` (snapshot year by default; `?year=all` for history; `&format=csv` for all matching rows)
- Relationship JSON: `/api/v1/mines/0405514/relationships`
- MCP resource: `mine://0405514/assessment`
- Complete Title 30 corpus: `/data/title30-sections.json`