# DeSilva Gates Aggregates

- **MSHA mine ID:** 0402098
- **Status:** Active
- **Type / commodity:** Surface / Construction Sand and Gravel
- **Location:** Alameda, CA
- **Operator:** DeSilva Gates Construction LLC
- **Controller:** De Silva Holding Company Inc; Richard B Gates
- **Public source rows linked:** 1,950
- **Source coverage:** 15 / 20
- **Generated:** 2026-10-13T11:26:59.401Z

## Current entity hierarchy

**De Silva Holding Company Inc; Richard B Gates (0170120) → DeSilva Gates Construction LLC (0065363) → DeSilva Gates Aggregates (0402098)**

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

## Controller and operator valid-time history

- **R K  Humphries → Santa Clara Sand & Gravel Company Inc:** 1950-01-01 through 1985-10-31; derived from co-tenure at mine 0402098; source `msha-controller-operator-history`.
- **Lone Star Industries Inc → Lone Star Industries Inc:** 1985-11-01 through 1987-12-31; derived from co-tenure at mine 0402098; source `msha-controller-operator-history`.
- **RMC Group PLC → CEMEX:** 1988-01-01 through 2005-02-28; derived from co-tenure at mine 0402098; source `msha-controller-operator-history`.
- **Cemex S A → CEMEX:** 2005-03-01 through 2006-11-30; derived from co-tenure at mine 0402098; source `msha-controller-operator-history`.
- **Cemex S A → Cemex Construction Materials LP:** 2006-12-01 through 2011-11-29; derived from co-tenure at mine 0402098; source `msha-controller-operator-history`.
- **DeSilva Holding Co → Sunol Aggregates:** 2011-11-30 through 2015-08-20; derived from co-tenure at mine 0402098; source `msha-controller-operator-history`.
- **Edwin O  DeSilva et al → DeSilva Gates Construction LLC:** 2015-08-21 through 2022-05-04; derived from co-tenure at mine 0402098; source `msha-controller-operator-history`.
- **Richard B  Gates et al → DeSilva Gates Construction LLC:** 2015-08-21 through 2022-05-04; derived from co-tenure at mine 0402098; source `msha-controller-operator-history`.
- **De Silva Holding Company Inc et al → DeSilva Gates Construction LLC:** 2022-05-05 through 2025-04-10; derived from co-tenure at mine 0402098; source `msha-controller-operator-history`.
- **Richard B Gates et al → DeSilva Gates Construction LLC:** 2022-05-05 through 2025-04-10; derived from co-tenure at mine 0402098; source `msha-controller-operator-history`.
- **El Portal Real Estate Co et al → DeSilva Gates Construction LLC:** 2025-04-11 through 2025-12-18; derived from co-tenure at mine 0402098; source `msha-controller-operator-history`.
- **Oliver DeSilva Inc et al → DeSilva Gates Construction LLC:** 2025-04-11 through 2025-12-18; derived from co-tenure at mine 0402098; source `msha-controller-operator-history`.
- **Richard B Gates et al → DeSilva Gates Construction LLC:** 2025-12-19 through current/open; derived from co-tenure at mine 0402098; source `msha-controller-operator-history`.
- **De Silva Holding Company Inc et al → DeSilva Gates Construction LLC:** 2025-12-19 through current/open; derived from co-tenure at mine 0402098; source `msha-controller-operator-history`.

- History rows: 14
- Typed edges: 30
- 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 — 2 since 2021:** Accidents and injuries 13 historical accident/injury rows; 0 coded fatalities and 195 lost days across the published record.
2. **COMPLIANCE — 19 since 2021:** Violations and penalties 244 violation rows across the full record; 58 carry an S&S flag and $43,511 appears in current assessed amounts.
3. **HEALTH — 29 samples:** Occupational health samples 29 personal. 1 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 9K employee hours and 17 summed average employees across reported subunits in the latest published quarter.
5. **LEGAL — 49 linked rows:** Contests, conferences and decisions 18 contested-violation rows, 18 civil-penalty docket/decision rows, and 13 conference records linked by issuance number.
6. **CONTRACTORS — 8 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 — 31 since 2021:** Inspections 97 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 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 56.20003 — 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 56.20010 — Retaining dams.** (3 retained recent rows) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-K/part-56/subpart-S/section-56.20010
- **30 CFR 56.11017 — Inclined fixed ladders.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-K/part-56/subpart-J/section-56.11017
- **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 56.11001 — Safe access.** (2 retained recent rows) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-K/part-56/subpart-J/section-56.11001
- **30 CFR 56.4601 — Oxygen cylinder storage.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-K/part-56/subpart-C/section-56.4601
- **30 CFR 56.14207 — Parking procedures for unattended equipment.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-K/part-56/subpart-M/section-56.14207

## Source coverage

- **Accident, Injuries, and Illnesses:** 13 rows; 2001-01-15 through 2026-06-02; source ID `msha-accidents`
- **Addresses of Record:** 1 rows; 1972-09-21 through 1972-09-21; source ID `msha-addresses`
- **Assessed Violations:** 242 rows; 2000-03-21 through 2026-07-28; source ID `msha-assessed-violations`
- **Civil Penalty Dockets and Decisions:** 18 rows; 2012-07-18 through 2023-07-28; source ID `msha-civil-penalty-dockets-decisions`
- **Conferences:** 13 rows; 2011-03-21 through 2026-09-23; source ID `msha-conferences`
- **Contested Violations:** 18 rows; 2011-06-02 through 2023-01-12; source ID `msha-contested-violations`
- **Contractor Employment and Production — Quarterly:** 812 rows; unknown through unknown; source ID `msha-contractor-production-quarterly`
- **Contractor Employment and Production — Yearly:** 184 rows; unknown through unknown; source ID `msha-contractor-production-yearly`
- **Controller and Operator History:** 14 rows; 1950-01-01 through 2015-08-21; source ID `msha-controller-operator-history`
- **Inspections:** 97 rows; 2000-03-21 through 2026-07-28; source ID `msha-inspections`
- **Mine Employment and Production — Quarterly:** 210 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:** 29 rows; 2000-10-12 through 2025-05-21; source ID `msha-personal-health-samples`
- **Violations:** 244 rows; 2000-03-21 through 2026-07-28; 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/desilva-gates-aggregates-0402098`
- JSON: `/api/v1/mines/desilva-gates-aggregates-0402098`
- Silica records, units, sample status and quarterly means: `/api/v1/mines/0402098/silica` (snapshot year by default; `?year=all` for history; `&format=csv` for all matching rows)
- Relationship JSON: `/api/v1/mines/0402098/relationships`
- MCP resource: `mine://0402098/assessment`
- Complete Title 30 corpus: `/data/title30-sections.json`