MSHA DATABASEMSHA records · 15 contributing sources · snapshot Oct 13, 2026

MINE DETAILS

Pacific Plant

ActiveSurfaceQuartz, Ground
MSHA MINE ID2300544
LOCATIONSt Louis, MO
PUBLIC RECORD2,318 linked rows

LOCATION

Mine location

1 of 1 mine with usable MSHA coordinates. Select a marker to open a mine.

Mine coordinates

2025-01-01 – 2026-10-13Applies to production, safety and portfolio metrics. Silica samples have separate filters.

Violations

11

3 significant & substantial (S&S)

  1. 2025 Q10
  2. 2025 Q24
  3. 2025 Q30
  4. 2025 Q42
  5. 2026 Q10
  6. 2026 Q25
  7. 2026 Q30
  8. 2026 Q4 *0

Accident records

1

0 records classified as fatality

  1. 2025 Q10
  2. 2025 Q20
  3. 2025 Q30
  4. 2025 Q40
  5. 2026 Q11
  6. 2026 Q20
  7. 2026 Q30
  8. 2026 Q4 *0

Proposed penalties · USD

4,371.00

11 of 11 violations with amounts

  1. 2025 Q1—
  2. 2025 Q22,998
  3. 2025 Q3—
  4. 2025 Q4302
  5. 2026 Q1—
  6. 2026 Q21,071
  7. 2026 Q3—
  8. 2026 Q4 *—

On-site inspection hours

86.25

4 inspections · 4 with hours

  1. 2025 Q1—
  2. 2025 Q242.25
  3. 2025 Q3—
  4. 2025 Q425.50
  5. 2026 Q1—
  6. 2026 Q218.50
  7. 2026 Q3—
  8. 2026 Q4 *—
Quarterly safety data
QuarterViolationsS&SProposed USDAccident recordsFatality recordsInspectionsOn-site hours
2025-Q100—000—
2025-Q2412,998.0000142.3
2025-Q300—000—
2025-Q420302.0000125.5
2026-Q100—100—
2026-Q2521,071.0000218.5
2026-Q300—000—
2026-Q4 *00—000—

Most cited CFR sections

All violations issued in the selected period. Counts combine subsections.

Safety activity

  1. inspectionF03861D

    Spot Inspection · 2.0 on-site hours

  2. violation5042354

    56.13011 · $151.00 proposed

  3. inspectionF03861C

    Regular Safety and Health Inspection · 16.5 on-site hours

  4. violation5042353

    56.11001 · $193.00 proposed

  5. violation5042352

    56.17001 · $151.00 proposed

  6. violation5042351

    56.9300(b) · S&S · $288.00 proposed

  7. violation5042350

    56.9300(b) · S&S · $288.00 proposed

  8. accident220260930013

    HANDLING OF MATERIALS · DAYS RESTRICTED ACTIVITY ONLY

    Accident narrative

    Employee was helping free a frozen switch when they lost grip and stumbled backwards. Right knee injury occurred and employee was able to continue work activities until surgery restrictions put into place on 3/26/2026

  9. violation9788850

    56.14112(b) · $151.00 proposed

  10. violation9788849

    56.11001 · $151.00 proposed

  11. inspectionF023A65

    Regular Safety and Health Inspection · 25.5 on-site hours

  12. violation9788361

    56.11001 · $151.00 proposed

  13. violation9788360

    56.14107(a) · $193.00 proposed

  14. violation9781980

    56.17001 · $151.00 proposed

  15. inspectionF011869

    Regular Safety and Health Inspection · 42.3 on-site hours

  16. violation9781977

    56.12030 · S&S · $2,503.00 proposed

Safety sources and definitions

MSHA Violations (issue date), Accidents (accident date), and Inspections (begin date). Snapshot 2026-10-13.

Counts describe published rows, including contractor records; accident records are not distinct incidents or numbers of people injured.

Zero means no matching records in the imported sources, not proof of no events. Historical coverage differs by source; absence before a source begins reporting is not a zero incident rate. Invalid or absent dates and records after the snapshot are excluded.

S&S means SIG_SUB=Y. Fatality records use DEGREE_INJURY_CD=01. Proposed penalties are not final assessed or paid amounts; missing dollar values are omitted.

Inspection hours are SUM_TOTAL_ON_SITE_HOURS attributed to the inspection start date, without supervisor/trainee hours. Missing hours are omitted; a started inspection may still be open.

Portfolio totals use current mine membership, including events before the current owner or operator's tenure.

CFR headings link to the current Title 30 index; they are not historical legal determinations.

OWNERSHIP

Operator and controller history

Current ownership comes from MSHA Mines. Historical start and end dates come from MSHA Controller and Operator History.

CURRENT HIERARCHYUSS Holdings Inc → U.S. Silica Company, LLC → Pacific Plant
HISTORY RECORDS39 relationships
INTERVAL CHECKPASScontroller/operator overlap
—

USS Holdings InccontrolsU.S. Silica Company, LLCoperatesPacific Plant

msha-controller-operator-history · controller/operator co-tenure derived on mine 2300544
—

Rio Tinto GroupcontrolsU S Silica CompanyoperatesPacific Plant

msha-controller-operator-history · controller/operator co-tenure derived on mine 2300544
—

ITT CorpcontrolsPennsylvania Glass Sand CorpoperatesPacific Plant

msha-controller-operator-history · controller/operator co-tenure derived on mine 2300544
Other historical summaries · source-specific periods

RECORD SUMMARY

Production, safety and enforcement

These summaries use the periods stated on each card, independently of the reporting period above.

01 / SAFETYwatch

Accidents and injuries

44 historical accident/injury rows; 0 coded fatalities and 974 lost days across the published record.

ACCIDENT + INJURY RECORD5 since 2021
accidentsmine-production-quarterly
02 / COMPLIANCEwatch

Violations and penalties

233 violation rows across the full record; 42 carry an S&S flag and $70,769 appears in current assessed amounts.

ENFORCEMENT ACTIVITY118 since 2021
inspectionsviolationsassessed-violationsorders-107a
03 / HEALTHwatch

Occupational health samples

147 personal. 14 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.

OCCUPATIONAL EXPOSURE147 samples
personal-health-samples
04 / PRODUCTIONcontext

Quarterly production and employment

30K employee hours and 54 summed average employees across reported subunits in the latest published quarter.

2026-Q20 tons
mine-production-quarterlymine-production-yearly
05 / LEGALwatch

Contests, conferences and decisions

58 contested-violation rows, 58 civil-penalty docket/decision rows, and 14 conference records linked by issuance number.

POST-ISSUANCE LIFECYCLE130 linked rows
conferencescontested-violationscivil-penalty-dockets-decisions
06 / CONTRACTORScontext

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.

ENTITY-LEVEL CONTEXT11 linked entities
contractor-production-quarterlycontractor-production-yearlyaccidentsviolations
07 / INSPECTIONScontext

Inspections

118 inspection events and 3K published inspection hours across the historical record.

OVERSIGHT COVERAGE33 since 2021
inspectionsviolations

HEALTH SAMPLING

Silica and quartz

Matching records00 coal · 0 personal · 0 area
Sample status0 not voided0 voided · 0 status not reported
Personal samples with C/E > 1—0 published ratios · not a citation count
2026 · No reported dates in this selection
Date / sampleDataset / analyteOccupation / areaMeasurementSample statusPublished action
No silica records match these filters. Missing samples do not establish safe conditions.
Sources and interpretation
  • Coal means use numeric concentrations from samples marked not voided, excluding control/invalid sample types and dates after the snapshot. Missing values remain null; reported zeroes remain zero.
  • Quarterly means describe available samples, not mine-wide or worker-average exposure. Quarters with no eligible measurements remain empty; the current quarter is partial.
  • Personal C/E is MSHA's published concentration-to-limit ratio. A value above 1 is not by itself a citation or a determination under the 2024 silica rule. Personal and area files do not publish a void-status field.
  • Area records include bulk-dust analyses and are kept separate from personal exposure results. Their concentration units are not specified in the source dictionary.
  • Missing samples do not establish safe conditions. Coal quartz percentage and concentration are separate measures. No compliance threshold is inferred for coal samples.

Coal quartz field definitions ↗Metal/nonmetal personal field definitions ↗Metal/nonmetal area field definitions ↗

EIA + TITLE 30

EIA production and cited regulations

EIA annual figures are reported separately from MSHA. Regulation links use the current eCFR snapshot.

RECENT PUBLIC RECORDS

Recent violations and samples

Latest records retained for inspection; aggregates above use the full source history.

VIOLATIONS12 latest shown
504235456.13011Citation
504235356.11001Citation
504235256.17001Citation
504235156.9300(b)S&S
504235056.9300(b)S&S
978885056.14112(b)Citation
978884956.11001Citation
978836156.11001Citation
OTHER HEALTH SAMPLES8 latest shown

Coal dust, noise and other contaminants. Silica records above ↑

Respirable dust, <.1mgKiln/Dryer Operator
C/E: 00.00Concentration: 0000.00 · limit: 0000.00Source unit unspecified
Respirable dust, <.1mgKiln/Dryer Operator
C/E: 00.00Concentration: 0000.00 · limit: 0000.00Source unit unspecified
Respirable dust, <.1mgBagging Operator
C/E: 00.00Concentration: 0000.00 · limit: 0000.00Source unit unspecified
Respirable dust, <.1mgLaborer, Bullgang
C/E: 00.00Concentration: 0000.00 · limit: 0000.00Source unit unspecified
Respirable dust, <.1mgBagging Operator
C/E: 00.00Concentration: 0000.00 · limit: 0000.00Source unit unspecified
Respirable dust, <.1mgRotary Bucket Ex. Operator
C/E: 00.00Concentration: 0000.00 · limit: 0000.00Source unit unspecified
Respirable dust, <.1mgBall Mill Operator
C/E: 00.00Concentration: 0000.00 · limit: 0000.00Source unit unspecified
Respirable dust, <.1mgPackaging Operations Worker
C/E: 00.00Concentration: 0000.00 · limit: 0000.00Source unit unspecified

SOURCE COVERAGE

Reporting dates and coverage

15 datasets contain linked records. Missing datasets are listed below.

DATASETROWSWINDOWSTATUS
Accident, Injuries, and Illnessessafety · contractors44May 8, 2000—Jan 31, 2026mine-keyed
Addresses of Recordidentity · logistics1Sep 9, 1975—Sep 9, 1975mine-keyed
Assessed Violationscompliance · legal230Feb 29, 2000—Jun 3, 2026mine-keyed
Civil Penalty Dockets and Decisionscompliance · legal58Nov 19, 2009—Jun 15, 2026mine-keyed
Coal Dust Sampleshealth · safety—No published rowsabsent / not applicable
Conferencescompliance · legal14May 5, 2000—Nov 26, 2025mine-keyed
Contested Violationscompliance · legal58Nov 25, 2008—Nov 24, 2025mine-keyed
Contractor Employment and Production — Quarterlycontractors · production · safety848Not published—Not publishedentity-linked
Contractor Employment and Production — Yearlycontractors · production · safety164Not published—Not publishedentity-linked
Controller and Operator Historyidentity · compliance3Jan 1, 1950—Mar 9, 1996mine-keyed
Mine Employment and Production — Quarterlyproduction · safety · compliance318Not published—Not publishedmine-keyed
Mine Employment and Production — Yearlyproduction · safety · compliance81Not published—Not publishedmine-keyed
Inspectionssafety · compliance118Feb 28, 2000—Jun 10, 2026mine-keyed
Minesidentity · production · logistics1Not published—Not publishedmine-keyed
Metal and Nonmetal Area Sampleshealth · safety—No published rowsabsent / not applicable
Metal and Nonmetal Personal Health Sampleshealth · safety147Aug 25, 2000—Jun 26, 2025mine-keyed
Noise Sampleshealth · safety · equipment—No published rowsabsent / not applicable
Quartz Samples — Coalhealth · safety—No published rowsabsent / not applicable
Violationscompliance · safety · legal233Feb 29, 2000—Jun 3, 2026mine-keyed
107(a) Orders Issuedsafety · compliance—No published rowsabsent / not applicable

NOTES

Limitations

  • Contractor production is entity-level and is never represented as mine-attributable.
  • Missing rows can mean no event, publication delay, identity mismatch, or inapplicability.