ACTIVE / OPERATOR PORTFOLIO

HI-GRADE MATERIALS CO.

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

MSHA OPERATOR IDL08509

MINE PORTFOLIO

4 of 4 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
HJ HOVE0401854 · Active6/8 quarters reportedRiverside, CASurface · MSHA: Construction Sand and Gravel054,81510033.0
Littlerock Quarry0404802 · Active6/8 quarters reportedLos Angeles, CASurface · MSHA: Construction Sand and Gravel089,32612076.5
Lucerne Valley Pit0403178 · Active6/8 quarters reportedSan Bernardino, CASurface · MSHA: Construction Sand and Gravel028,4274123.5
ROBERT E HOVE PIT0401807 · Active6/8 quarters reportedSan Bernardino, CASurface · MSHA: Construction Sand and Gravel026,18822340.5

LOCATION

Portfolio map

4 of 4 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

48

12 significant & substantial (S&S)

  1. 2025 Q112
  2. 2025 Q28
  3. 2025 Q30
  4. 2025 Q40
  5. 2026 Q115
  6. 2026 Q212
  7. 2026 Q31
  8. 2026 Q4 *0

Accident records

4

0 records classified as fatality

  1. 2025 Q11
  2. 2025 Q20
  3. 2025 Q31
  4. 2025 Q40
  5. 2026 Q11
  6. 2026 Q20
  7. 2026 Q31
  8. 2026 Q4 *0

Proposed penalties · USD

20,606.00

48 of 48 violations with amounts

  1. 2025 Q12,330
  2. 2025 Q26,979
  3. 2025 Q3—
  4. 2025 Q4—
  5. 2026 Q14,246
  6. 2026 Q26,900
  7. 2026 Q3151
  8. 2026 Q4 *—

On-site inspection hours

173.50

28 inspections · 28 with hours

  1. 2025 Q128.50
  2. 2025 Q224.50
  3. 2025 Q319.50
  4. 2025 Q41.50
  5. 2026 Q144.00
  6. 2026 Q240.00
  7. 2026 Q315.50
  8. 2026 Q4 *—
Quarterly safety data
QuarterViolationsS&SProposed USDAccident recordsFatality recordsInspectionsOn-site hours
2025-Q11202,330.0010328.5
2025-Q2846,979.0000524.5
2025-Q300—10419.5
2025-Q400—0011.5
2026-Q11534,246.0010644.0
2026-Q21256,900.0000540.0
2026-Q310151.0010415.5
2026-Q4 *00—000—

Most cited CFR sections

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

Safety activity

  1. violation9890420
    Littlerock Quarry · 0404802

    56.16006 · $151.00 proposed

  2. violation9890419
    Littlerock Quarry · 0404802

    56.14205 · $151.00 proposed

  3. violation9890418
    Littlerock Quarry · 0404802

    56.16006 · $151.00 proposed

  4. violation9890417
    Littlerock Quarry · 0404802

    56.12018 · $151.00 proposed

  5. inspectionF01D81F
    Littlerock Quarry · 0404802

    Regular Safety and Health Inspection · 21.0 on-site hours

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.