MSHA DATABASEMSHA records · 12 contributing sources · snapshot Oct 13, 2026

MINE DETAILS

Big Seam mine

ActiveUndergroundGold Ore
MSHA MINE ID0404468
LOCATIONPlacer, CA
PUBLIC RECORD349 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

2

0 significant & substantial (S&S)

  1. 2025 Q10
  2. 2025 Q20
  3. 2025 Q31
  4. 2025 Q40
  5. 2026 Q10
  6. 2026 Q21
  7. 2026 Q30
  8. 2026 Q4 *0

Accident records

0

0 records classified as fatality

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

Proposed penalties · USD

302.00

2 of 2 violations with amounts

  1. 2025 Q1—
  2. 2025 Q2—
  3. 2025 Q3151
  4. 2025 Q4—
  5. 2026 Q1—
  6. 2026 Q2151
  7. 2026 Q3—
  8. 2026 Q4 *—

On-site inspection hours

101.00

11 inspections · 11 with hours

  1. 2025 Q111.50
  2. 2025 Q236.25
  3. 2025 Q313.00
  4. 2025 Q47.00
  5. 2026 Q15.75
  6. 2026 Q222.75
  7. 2026 Q34.75
  8. 2026 Q4 *—
Quarterly safety data
QuarterViolationsS&SProposed USDAccident recordsFatality recordsInspectionsOn-site hours
2025-Q100—00111.5
2025-Q200—00436.3
2025-Q310151.0000113.0
2025-Q400—0017.0
2026-Q100—0015.8
2026-Q210151.0000222.8
2026-Q300—0014.8
2026-Q4 *00—000—

Most cited CFR sections

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

Safety activity

  1. inspectionF034D6D

    Regular Safety and Health Inspection · 4.8 on-site hours

  2. inspectionF022F4E

    Regular Safety and Health Inspection · 6.5 on-site hours

  3. violation5105207

    57.8520 · $151.00 proposed

  4. inspectionF00E45C

    Ventilation Technical Investigation · 16.3 on-site hours

  5. inspectionF025DB6

    Regular Safety and Health Inspection · 5.8 on-site hours

  6. inspectionF022F40

    Regular Safety and Health Inspection · 7.0 on-site hours

  7. inspectionF022F2D

    Regular Safety and Health Inspection · 13.0 on-site hours

  8. violation9890802

    57.11051(a) · $151.00 proposed

  9. inspection6880756

    Health Technical Investigation · 2.5 on-site hours

  10. inspectionF022F2B

    Ventilation Technical Investigation · 9.8 on-site hours

  11. inspectionF016570

    Special Emphasis Programs · 12.0 on-site hours

  12. inspectionF013F2F

    Regular Safety and Health Inspection · 12.0 on-site hours

  13. inspection6963971

    Regular Safety and Health Inspection · 11.5 on-site hours

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 HIERARCHYFocused Mining Enterprises LLC → Eagle's Nest Mining LLC → Big Seam mine
HISTORY RECORDS39 relationships
INTERVAL CHECKPASScontroller/operator overlap
—

Focused Mining Enterprises LLCcontrolsEagle's Nest Mining LLCoperatesBig Seam mine

msha-controller-operator-history · controller/operator co-tenure derived on mine 0404468
—

Richard R SykoracontrolsWildcat Mining LLCoperatesBig Seam mine

msha-controller-operator-history · controller/operator co-tenure derived on mine 0404468
—

John R De Maria SrcontrolsJohn R De MariaoperatesBig Seam mine

msha-controller-operator-history · controller/operator co-tenure derived on mine 0404468
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

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

ACCIDENT + INJURY RECORD1 since 2021
accidentsmine-production-quarterly
02 / COMPLIANCEwatch

Violations and penalties

42 violation rows across the full record; 3 carry an S&S flag and $5,898 appears in current assessed amounts.

ENFORCEMENT ACTIVITY29 since 2021
inspectionsviolationsassessed-violationsorders-107a
03 / HEALTHcontext

Occupational health samples

2 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.

OCCUPATIONAL EXPOSURE2 samples
personal-health-samples
04 / PRODUCTIONcontext

Quarterly production and employment

4K employee hours and 7 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

0 contested-violation rows, 1 civil-penalty docket/decision rows, and 6 conference records linked by issuance number.

POST-ISSUANCE LIFECYCLE7 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 CONTEXT0 linked entities
contractor-production-quarterlycontractor-production-yearlyaccidentsviolations
07 / INSPECTIONScontext

Inspections

65 inspection events and 879 published inspection hours across the historical record.

OVERSIGHT COVERAGE36 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
510520757.8520Citation
989080257.11051(a)Citation
999982750.30(a)Citation
961176249.3(c)Citation
950790657.12023Citation
950787547.51Citation
961915456.18013Citation
961915357.12032Citation
OTHER HEALTH SAMPLES1 latest shown

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

Respirable dust, <.1mgScaling (hand)
C/E: 00.00Concentration: 0000.00 · limit: 0000.00Source unit unspecified

SOURCE COVERAGE

Reporting dates and coverage

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

DATASETROWSWINDOWSTATUS
Accident, Injuries, and Illnessessafety · contractors1Mar 1, 2022—Mar 1, 2022mine-keyed
Addresses of Recordidentity · logistics1Jan 18, 2023—Jan 18, 2023mine-keyed
Assessed Violationscompliance · legal40Nov 28, 2000—Apr 7, 2026mine-keyed
Civil Penalty Dockets and Decisionscompliance · legal1Jul 18, 2023—Jul 18, 2023mine-keyed
Coal Dust Sampleshealth · safety—No published rowsabsent / not applicable
Conferencescompliance · legal6May 10, 2010—Sep 6, 2022mine-keyed
Contested Violationscompliance · legal—No published rowsabsent / not applicable
Contractor Employment and Production — Quarterlycontractors · production · safety—No published rowsabsent / not applicable
Contractor Employment and Production — Yearlycontractors · production · safety—No published rowsabsent / not applicable
Controller and Operator Historyidentity · compliance3Oct 1, 1980—Apr 22, 2020mine-keyed
Mine Employment and Production — Quarterlyproduction · safety · compliance143Not published—Not publishedmine-keyed
Mine Employment and Production — Yearlyproduction · safety · compliance44Not published—Not publishedmine-keyed
Inspectionssafety · compliance65Jan 20, 2000—Aug 3, 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 · safety2Jan 13, 2021—Apr 13, 2022mine-keyed
Noise Sampleshealth · safety · equipment—No published rowsabsent / not applicable
Quartz Samples — Coalhealth · safety—No published rowsabsent / not applicable
Violationscompliance · safety · legal42Nov 28, 2000—Apr 7, 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.