ACTIVE / CONTROLLER PORTFOLIO

Natural Resource Partners LP; Ciner Resources LP

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

MSHA CONTROLLER ID0107927

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. inspectionF019AD0
    Big Island Mine & Refinery · 4800154

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

  2. inspectionF027679
    Big Island Mine & Refinery · 4800154

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

  3. violation5051558
    Big Island Mine & Refinery · 4800154

    49.6(b)(1) · $959.00 proposed

  4. inspectionF012575
    Big Island Mine & Refinery · 4800154

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

  5. inspectionF01B357
    Big Island Mine & Refinery · 4800154

    Impoundment Spot Inspection · 4.5 on-site hours

  6. inspectionF019AC9
    Big Island Mine & Refinery · 4800154

    103(i) Spot Inspections · 2.0 on-site hours

  7. violation5051552
    Big Island Mine & Refinery · 4800154

    57.14207 · $288.00 proposed

  8. violation5050575
    Big Island Mine & Refinery · 4800154

    57.4601 · $151.00 proposed

  9. violation5050574
    Big Island Mine & Refinery · 4800154

    57.4601 · $151.00 proposed

  10. violation5050573
    Big Island Mine & Refinery · 4800154

    57.12028 · $226.00 proposed

  11. violation5050572
    Big Island Mine & Refinery · 4800154

    57.14107(a) · $193.00 proposed

  12. violation5050571
    Big Island Mine & Refinery · 4800154

    57.12018 · $151.00 proposed

  13. violation5050570
    Big Island Mine & Refinery · 4800154

    57.12002 · $288.00 proposed

  14. violation5050569
    Big Island Mine & Refinery · 4800154

    57.12032 · $151.00 proposed

  15. violation5050568
    Big Island Mine & Refinery · 4800154

    57.12028 · $226.00 proposed

  16. violation9905423
    Big Island Mine & Refinery · 4800154

    57.14107(a) · $193.00 proposed

  17. violation9905236
    Big Island Mine & Refinery · 4800154

    57.12032 · $151.00 proposed

  18. violation5050567
    Big Island Mine & Refinery · 4800154

    57.4602 · $151.00 proposed

  19. violation5050566
    Big Island Mine & Refinery · 4800154

    57.4101 · $151.00 proposed

  20. violation5050565
    Big Island Mine & Refinery · 4800154

    57.14207 · $151.00 proposed

  21. violation5050564
    Big Island Mine & Refinery · 4800154

    57.12004 · $151.00 proposed

  22. violation5050563
    Big Island Mine & Refinery · 4800154

    57.4603(b) · $151.00 proposed

  23. violation5050562
    Big Island Mine & Refinery · 4800154

    57.12004 · $151.00 proposed

  24. violation5050561
    Big Island Mine & Refinery · 4800154

    57.12028 · $226.00 proposed

  25. violation5050560
    Big Island Mine & Refinery · 4800154

    57.12028 · $226.00 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 operator.

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