ACTIVE / OPERATOR PORTFOLIO

Knife River - South Dakota

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

MSHA OPERATOR IDL15666

MINE PORTFOLIO

3 of 3 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
Corson Sand Plant / Quarry3901478 · Active6/8 quarters reportedMinnehaha, SDSurface · MSHA: Quartz, Ground035,28312345.8
Knife River Portable Plant SD-13900292 · Active6/8 quarters reportedMinnehaha, SDSurface · MSHA: Construction Sand and Gravel014,0090012.3
Sioux Falls Quarry3900008 · Active6/8 quarters reportedMinnehaha, SDSurface · MSHA: Crushed, Broken Quartzite0128,66623292.3

LOCATION

Portfolio map

3 of 3 mines 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

35

6 significant & substantial (S&S)

  1. 2025 Q10
  2. 2025 Q27
  3. 2025 Q30
  4. 2025 Q45
  5. 2026 Q11
  6. 2026 Q219
  7. 2026 Q30
  8. 2026 Q4 *3

Accident records

5

0 records classified as fatality

  1. 2025 Q10
  2. 2025 Q20
  3. 2025 Q32
  4. 2025 Q40
  5. 2026 Q11
  6. 2026 Q20
  7. 2026 Q32
  8. 2026 Q4 *0

Proposed penalties · USD

5,383.00

32 of 35 violations with amounts

  1. 2025 Q1—
  2. 2025 Q21,251
  3. 2025 Q3—
  4. 2025 Q4755
  5. 2026 Q1151
  6. 2026 Q23,226
  7. 2026 Q3—
  8. 2026 Q4 *—

On-site inspection hours

150.25

11 inspections · 11 with hours

  1. 2025 Q1—
  2. 2025 Q237.25
  3. 2025 Q33.75
  4. 2025 Q410.75
  5. 2026 Q119.50
  6. 2026 Q261.00
  7. 2026 Q318.00
  8. 2026 Q4 *—
Quarterly safety data
QuarterViolationsS&SProposed USDAccident recordsFatality recordsInspectionsOn-site hours
2025-Q100—000—
2025-Q2711,251.0000237.3
2025-Q300—2013.8
2025-Q450755.0000110.8
2026-Q110151.0010219.5
2026-Q21923,226.0000361.0
2026-Q300—20218.0
2026-Q4 *33—000—

Most cited CFR sections

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

Safety activity

  1. inspectionF0376A5
    Corson Sand Plant / Quarry · 3901478

    Regular Safety and Health Inspection · 19.5 on-site hours

  2. violation5113556
    Corson Sand Plant / Quarry · 3901478

    56.4201(a)(2) · $151.00 proposed

  3. violation5113555
    Corson Sand Plant / Quarry · 3901478

    56.14100(c) · $151.00 proposed

  4. violation5113554
    Corson Sand Plant / Quarry · 3901478

    56.4201(a)(2) · $151.00 proposed

  5. accident220260200053
    Sioux Falls Quarry · 3900008

    HANDTOOLS (NONPOWERED) · NO DYS AWY FRM WRK,NO RSTR ACT

    Accident narrative

    Employee was assisting with the replacement of a head-drum shaft bearing on the #1 screen conveyor on the Portable Plant. The chain that was used to support the head-drum and shaft assembly snapped, striking Tyler Whipple middle finger on left hand, fracturing the 3rd digit / tip of finger.

  6. inspectionF0231E6
    Knife River Portable Plant SD-1 · 3900292

    Regular Safety and Health Inspection · 3.3 on-site hours

  7. violation5113504
    Sioux Falls Quarry · 3900008

    56.12004 · $151.00 proposed

  8. inspectionF0231E5
    Sioux Falls Quarry · 3900008

    Regular Safety and Health Inspection · 16.3 on-site hours

  9. violation5113499
    Corson Sand Plant / Quarry · 3901478

    50.30(a) · $151.00 proposed

  10. violation5113498
    Corson Sand Plant / Quarry · 3901478

    50.30(a) · $151.00 proposed

  11. inspectionF0231E0
    Corson Sand Plant / Quarry · 3901478

    Regular Safety and Health Inspection · 10.8 on-site hours

  12. violation5113497
    Corson Sand Plant / Quarry · 3901478

    56.14211(c) · $151.00 proposed

  13. violation5113496
    Corson Sand Plant / Quarry · 3901478

    56.14206(b) · $151.00 proposed

  14. violation5113495
    Corson Sand Plant / Quarry · 3901478

    56.14206(b) · $151.00 proposed

  15. inspectionF028A81
    Knife River Portable Plant SD-1 · 3900292

    Regular Safety and Health Inspection · 3.8 on-site hours

  16. accident220252460029
    Sioux Falls Quarry · 3900008

    HANDLING OF MATERIALS · DAYS RESTRICTED ACTIVITY ONLY

    Accident narrative

    Team members replacing return roller, shaft began to slip, team member grabbed the shaft, causing pain to the right wrist.

  17. accident220252230017
    Corson Sand Plant / Quarry · 3901478

    HANDLING OF MATERIALS · NO DYS AWY FRM WRK,NO RSTR ACT

    Accident narrative

    Team member installing new exhaust gaskets, bolting up the flanges when debris fell onto and behind safety glasses, into right eye. Flushed eyes at the shop, debris remained behind eyelid.

  18. inspectionF02FADE
    Corson Sand Plant / Quarry · 3901478

    Regular Safety and Health Inspection · 13.5 on-site hours

  19. violation9699758
    Sioux Falls Quarry · 3900008

    56.12028 · $177.00 proposed

  20. violation9699756
    Sioux Falls Quarry · 3900008

    56.12018 · $151.00 proposed

  21. inspectionF0174F3
    Sioux Falls Quarry · 3900008

    Regular Safety and Health Inspection · 23.8 on-site hours

  22. violation9699755
    Sioux Falls Quarry · 3900008

    56.14207 · $151.00 proposed

  23. violation9699754
    Sioux Falls Quarry · 3900008

    56.9301 · S&S · $267.00 proposed

  24. violation9699753
    Sioux Falls Quarry · 3900008

    56.14207 · $177.00 proposed

  25. violation9699752
    Sioux Falls Quarry · 3900008

    56.12004 · $151.00 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.