Carmeuse Holding SA safety activity
MSHA violations, accident reports and inspections across the current mine portfolio.
Safety activity
Housekeeping.
LONGVIEW OPERATION · 010039430 CFR 56.20003(a) · Significant and substantial (S&S) · $366.00 proposed penalty
Non-Injury Accident Investigation
Maysville Mine · 15071018.5 on-site hours reported
Spot Inspection
O-N Minerals, Cedarville Operation · 20000616.3 on-site hours reported
Impoundment Spot Inspection
O-N Minerals, Cedarville Operation · 20000613.0 on-site hours reported
Regular Safety and Health Inspection
Middletown Quarry · 440004918.0 on-site hours reported
Records of training.
O-N Minerals, Cedarville Operation · 200006130 CFR 46.9(b)(5) · $151.00 proposed penalty
Examination of working places.
O-N Minerals, Cedarville Operation · 200006130 CFR 56.18002(b) · Significant and substantial (S&S) · $4,047.00 proposed penalty
Fire
Maysville Mine · 1507101Accident only
Accident narrative
On 3/10/2026 6:30 p.m. management was made aware that the surface trash compactor storage container had material inside on fire. This metal container measures eight feet by 22 feet and is used to transport trash from the mine property to an offsite dump. MSHA was notified and the fire was extinguished. There was no damage to property or injury due to this incident.
Inspection and cover plates.
LONGVIEW OPERATION · 010039430 CFR 56.12032 · $151.00 proposed penalty
Housekeeping.
LONGVIEW OPERATION · 010039430 CFR 56.20003(a) · $151.00 proposed penalty
Construction and maintenance of guards.
LONGVIEW OPERATION · 010039430 CFR 56.14112(b) · Significant and substantial (S&S) · $1,818.00 proposed penalty
Inspection and cover plates.
LONGVIEW OPERATION · 010039430 CFR 56.12032 · $151.00 proposed penalty
Regular Safety and Health Inspection
LONGVIEW OPERATION · 010039469.0 on-site hours reported
Impoundment Spot Inspection
O-N Minerals - Calcite Operation · 20000622.8 on-site hours reported
Examination of working places.
O-N Minerals, Cedarville Operation · 200006130 CFR 56.18002(a) · Significant and substantial (S&S) · $29,904.00 proposed penalty
New task training.
O-N Minerals, Cedarville Operation · 200006130 CFR 46.7(a) · Significant and substantial (S&S) · $29,904.00 proposed penalty
Slip or fall of person
Buffington Plant · 1200426Days restricted activity only
Accident narrative
Employee was coming in to begin the shift when they slipped (no fall) in water on the men's locker room floor. They reported the incident to their supervisor but did not seek medical attention until 4/6/2026 and was given work restrictions.
Hoisting
Maysville Mine · 1507101Accident only
Accident narrative
On 3/6/2026 3:20 a.m. management was made aware power had been lost to the slope hoist. This being the secondary escapeway, all mine personnel were evacuated using the primary escapeway. MSHA was notified when power restored at 4:02 a.m. No miners were injured due to this incident.
Inspection and cover plates.
Chesney Underground · 400211330 CFR 57.12032 · $151.00 proposed penalty
Safety belts and lines.
O-N Minerals, Cedarville Operation · 200006130 CFR 56.15005 · Significant and substantial (S&S) · $11,450.00 proposed penalty
Protection for openings around travelways.
O-N Minerals, Cedarville Operation · 200006130 CFR 56.11012 · Significant and substantial (S&S) · $38,016.00 proposed penalty
First-aid materials.
O-N Minerals, Cedarville Operation · 200006130 CFR 56.15001 · $465.00 proposed penalty
Compliance Follow-up Inspection
Buffington Plant · 12004262.5 on-site hours reported
103 (g) Written Notification Hazard Complaint Inspectio
O-N Minerals, Cedarville Operation · 20000616.0 on-site hours reported
Safe access.
Chesney Underground · 400211330 CFR 57.11001 · $151.00 proposed penalty
Sources and definitions
MSHA Violations (issue date), Accidents (accident date) and Inspections (begin date).
Violation titles use current CFR headings to identify the cited rule; they are not the inspector’s account of what happened.
Status is from the current MSHA Mines snapshot, not the selected reporting period. Closed records can retain their last reported controller/operator.
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.