# Columbus Limestone

- **MSHA mine ID:** 3304657
- **Status:** Active
- **Type / commodity:** Surface / Crushed, Broken Limestone NEC
- **Location:** Franklin, OH
- **Operator:** Shelly Materials Inc
- **Controller:** CRH PLC
- **Public source rows linked:** 5,439
- **Source coverage:** 16 / 20
- **Generated:** 2026-10-13T11:26:59.401Z

## Current entity hierarchy

**CRH PLC (M06183) → Shelly Materials Inc (L17597) → Columbus Limestone (3304657)**

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

## Controller and operator valid-time history

- **CRH PLC → Shelly Materials Inc:** 2010-09-30 through current/open; derived from co-tenure at mine 3304657; source `msha-controller-operator-history`.

- History rows: 1
- Typed edges: 3
- 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 — 10 since 2021:** Accidents and injuries 24 historical accident/injury rows; 0 coded fatalities and 466 lost days across the published record.
2. **COMPLIANCE — 121 since 2021:** Violations and penalties 272 violation rows across the full record; 75 carry an S&S flag and $84,509 appears in current assessed amounts.
3. **HEALTH — 140 samples:** Occupational health samples 134 personal; 6 area. 7 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 37K employee hours and 75 summed average employees across reported subunits in the latest published quarter.
5. **LEGAL — 27 linked rows:** Contests, conferences and decisions 11 contested-violation rows, 11 civil-penalty docket/decision rows, and 5 conference records linked by issuance number.
6. **CONTRACTORS — 20 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 — 41 since 2021:** Inspections 114 inspection events and 3K 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 56.11001 — 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 48.26 — Experienced miner training.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-H/part-48/subpart-B/section-48.26
- **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 56.11009 — Walkways along conveyors.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-K/part-56/subpart-J/section-56.11009
- **30 CFR 56.4203 — Extinguisher recharging or replacement.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-K/part-56/subpart-C/section-56.4203
- **30 CFR 56.14100 — Safety defects; examination, correction and records.** (4 retained recent rows) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-K/part-56/subpart-M/section-56.14100
- **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.** (1 retained recent row) — https://www.ecfr.gov/current/title-30/chapter-I/subchapter-K/part-56/subpart-S/section-56.20003

## Source coverage

- **Accident, Injuries, and Illnesses:** 24 rows; 2011-12-13 through 2026-07-20; source ID `msha-accidents`
- **Addresses of Record:** 1 rows; 2011-10-03 through 2011-10-03; source ID `msha-addresses`
- **Metal and Nonmetal Area Samples:** 6 rows; 2013-06-19 through 2015-06-02; source ID `msha-area-samples`
- **Assessed Violations:** 268 rows; 2011-01-24 through 2026-08-25; source ID `msha-assessed-violations`
- **Civil Penalty Dockets and Decisions:** 11 rows; 2016-11-10 through 2026-08-03; source ID `msha-civil-penalty-dockets-decisions`
- **Conferences:** 5 rows; 2013-06-04 through 2025-04-28; source ID `msha-conferences`
- **Contested Violations:** 11 rows; 2016-05-09 through 2025-12-10; source ID `msha-contested-violations`
- **Contractor Employment and Production — Quarterly:** 3,534 rows; unknown through unknown; source ID `msha-contractor-production-quarterly`
- **Contractor Employment and Production — Yearly:** 781 rows; unknown through unknown; source ID `msha-contractor-production-yearly`
- **Controller and Operator History:** 1 rows; 2010-09-30 through 2010-09-30; source ID `msha-controller-operator-history`
- **Inspections:** 114 rows; 2010-11-03 through 2026-08-10; source ID `msha-inspections`
- **Mine Employment and Production — Quarterly:** 217 rows; unknown through unknown; source ID `msha-mine-production-quarterly`
- **Mine Employment and Production — Yearly:** 59 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:** 134 rows; 2011-12-07 through 2025-12-09; source ID `msha-personal-health-samples`
- **Violations:** 272 rows; 2011-01-24 through 2026-08-25; 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/columbus-limestone-3304657`
- JSON: `/api/v1/mines/columbus-limestone-3304657`
- Silica records, units, sample status and quarterly means: `/api/v1/mines/3304657/silica` (snapshot year by default; `?year=all` for history; `&format=csv` for all matching rows)
- Relationship JSON: `/api/v1/mines/3304657/relationships`
- MCP resource: `mine://3304657/assessment`
- Complete Title 30 corpus: `/data/title30-sections.json`