ACTIVE / OPERATOR PORTFOLIO

Sisecam Wyoming, LLC

Membership and operating status are from the latest MSHA Mines snapshot. Open a mine for its ownership history.

MSHA OPERATOR IDL14409

MINE PORTFOLIO

1 of 1 mines and facilities

2025-01-01 – 2026-10-18. Active records; production reporting is not required.

MineLocation / typeCoal · short tonsHours workedViolationsAccident recordsOn-site inspection hours
Big Island Mine & Refinery4800154 · Active6/8 quarters reportedSweetwater, WYUnderground · MSHA: Trona01,271,63213951,580.3

LOCATION

Mine location

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

Mine coordinates

2025-01-01 – 2026-10-18Applies to production, safety and portfolio metrics. Silica samples have separate filters.

Violations

139

8 significant & substantial (S&S)

  1. 2025 Q112
  2. 2025 Q222
  3. 2025 Q330
  4. 2025 Q428
  5. 2026 Q112
  6. 2026 Q223
  7. 2026 Q312
  8. 2026 Q4 *0

Accident records

5

0 records classified as fatality

  1. 2025 Q10
  2. 2025 Q23
  3. 2025 Q30
  4. 2025 Q40
  5. 2026 Q10
  6. 2026 Q21
  7. 2026 Q31
  8. 2026 Q4 *0

Proposed penalties · USD

33,968.00

131 of 139 violations with amounts

  1. 2025 Q12,099
  2. 2025 Q24,883
  3. 2025 Q37,058
  4. 2025 Q49,354
  5. 2026 Q11,882
  6. 2026 Q24,422
  7. 2026 Q34,270
  8. 2026 Q4 *—

On-site inspection hours

1,580.25

81 inspections · 81 with hours

  1. 2025 Q1179.75
  2. 2025 Q2271.75
  3. 2025 Q3165.00
  4. 2025 Q4252.25
  5. 2026 Q1250.75
  6. 2026 Q2281.50
  7. 2026 Q3174.75
  8. 2026 Q4 *4.50
Quarterly safety data
QuarterViolationsS&SProposed USDAccident recordsFatality recordsInspectionsOn-site hours
2025-Q11202,099.000010179.8
2025-Q22224,883.003013271.8
2025-Q33007,058.000011165.0
2025-Q42829,354.000012252.3
2026-Q11201,882.000012250.8
2026-Q22334,422.001011281.5
2026-Q31214,270.001011174.8
2026-Q4 *00—0014.5

Most cited CFR sections

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

Safety activity

  1. inspectionF03CC81
    Big Island Mine & Refinery · 4800154

    103(i) Spot Inspections · 3.3 on-site hours

  2. inspectionF02FE9C
    Big Island Mine & Refinery · 4800154

    103(i) Spot Inspections · 5.0 on-site hours

  3. inspectionF01741F
    Big Island Mine & Refinery · 4800154

    103(i) Spot Inspections · 3.0 on-site hours

  4. inspectionF014CF8
    Big Island Mine & Refinery · 4800154

    103(i) Spot Inspections · 3.5 on-site hours

  5. inspectionF02FE92
    Big Island Mine & Refinery · 4800154

    103(i) Spot Inspections · 5.0 on-site hours

  6. accident220261470009
    Big Island Mine & Refinery · 4800154

    MACHINERY · ACCIDENT ONLY

    Accident narrative

    Lost incoming power from Rocky Mountain Power. Mine fans were lost and mine was evacuated. Notified MSHA. Power was restored at 7:00pm and miners returned to the mine by 10:30pm.

  7. inspectionF014CF5
    Big Island Mine & Refinery · 4800154

    103(i) Spot Inspections · 4.0 on-site hours

  8. inspectionF017416
    Big Island Mine & Refinery · 4800154

    103(i) Spot Inspections · 3.5 on-site hours

  9. inspectionF027091
    Big Island Mine & Refinery · 4800154

    103(i) Spot Inspections · 1.5 on-site hours

  10. violation9905264
    Big Island Mine & Refinery · 4800154

    57.14207 · $151.00 proposed

  11. inspectionF0276A2
    Big Island Mine & Refinery · 4800154

    Impoundment Spot Inspection · 5.8 on-site hours

  12. violation5057447
    Big Island Mine & Refinery · 4800154

    57.11001 · S&S

  13. violation5057446
    Big Island Mine & Refinery · 4800154

    57.11001 · S&S

  14. violation5057445
    Big Island Mine & Refinery · 4800154

    57.11003

  15. violation5057966
    Big Island Mine & Refinery · 4800154

    57.14100(d) · $151.00 proposed

  16. violation5057965
    Big Island Mine & Refinery · 4800154

    57.4201(a)(2) · $267.00 proposed

  17. violation5057964
    Big Island Mine & Refinery · 4800154

    57.12004 · $267.00 proposed

  18. violation5057963
    Big Island Mine & Refinery · 4800154

    57.4201(a)(1) · $151.00 proposed

  19. violation5051641
    Big Island Mine & Refinery · 4800154

    57.12004 · $432.00 proposed

  20. violation5051640
    Big Island Mine & Refinery · 4800154

    57.4102 · $151.00 proposed

  21. violation5051639
    Big Island Mine & Refinery · 4800154

    57.14107(a) · $193.00 proposed

  22. violation5051638
    Big Island Mine & Refinery · 4800154

    57.12004 · $151.00 proposed

  23. violation5057962
    Big Island Mine & Refinery · 4800154

    57.20003(a) · S&S · $432.00 proposed

  24. violation5057961
    Big Island Mine & Refinery · 4800154

    57.14100(b) · $151.00 proposed

  25. violation5057959
    Big Island Mine & Refinery · 4800154

    57.12023 · $288.00 proposed

Safety sources and definitions

MSHA Violations (issue date), Accidents (accident date), and Inspections (begin date). Snapshot 2026-10-18.

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.

SELECTED PORTFOLIO

1 linked controller.

Relationships reflect the selected mine status and current MSHA controller/operator fields.