O-N Minerals (Michigan) Company safety activity
MSHA violations, accident reports and inspections across the current mine portfolio.
Safety activity
Regular Safety and Health Inspection
O-N Minerals, Cedarville Operation · 200006119.0 on-site hours reported
Housekeeping.
Carmeuse - Port Inland Operation · 200098530 CFR 56.20003(a) · $151.00 proposed penalty
Handling of materials
O-N Minerals - Calcite Operation · 2000062No dys awy frm wrk,no rstr act
Accident narrative
ee was removing idlers from conveyor for a belt change. when they went to move the idler to the floor, their finger got pinched/rolled in between the cans causing a laceration / split to right pinky finger.
Closure of valves.
Carmeuse - Port Inland Operation · 200098530 CFR 56.4603(b) · $151.00 proposed penalty
Horns and backup alarms.
Carmeuse - Port Inland Operation · 200098530 CFR 56.14132(a) · $151.00 proposed penalty
Regular Safety and Health Inspection
Carmeuse - Port Inland Operation · 200098541.0 on-site hours reported
Horns and backup alarms.
Carmeuse - Port Inland Operation · 200098530 CFR 56.14132(a) · $151.00 proposed penalty
Impoundment Spot Inspection
O-N Minerals - Calcite Operation · 20000621.8 on-site hours reported
Housekeeping.
Carmeuse - Port Inland Operation · 200098530 CFR 56.20003(a) · Significant and substantial (S&S) · $177.00 proposed penalty
Housekeeping.
Carmeuse - Port Inland Operation · 200098530 CFR 56.20003(a) · Significant and substantial (S&S) · $398.00 proposed penalty
Combustible waste.
Carmeuse - Port Inland Operation · 200098530 CFR 56.4104(b) · Significant and substantial (S&S) · $504.00 proposed penalty
Regular Safety and Health Inspection
Carmeuse - Port Inland Operation · 200098532.3 on-site hours reported
Handling of materials
O-N Minerals, Cedarville Operation · 2000061Dys awy frm wrk & restrctd act
Accident narrative
ee was pulling the slack out of a wash hose when they felt a pop in their back. Incident occurred on 8/15/2025 - ee was evaluated by medical professional and released to work without restrictions. Pain was not getting better so went back to the doctor and was put off work on 9/8/2025.
Handling of materials
O-N Minerals - Calcite Operation · 2000062Dys awy frm wrk & restrctd act
Accident narrative
ee was throwing scrap steel into the skip when EE reaggravated a strain in EE's shoulder that occurred the day before.
Nonpowered haulage
O-N Minerals - Calcite Operation · 2000062Days restricted activity only
Accident narrative
employee was pushing a welding cart across the shop. one of the wheels fell into a low spot/crack in the concrete causing the cart to tilt. Employee reactively reached out with EE's arm to try to catch it in case it fell and felt a strain in EE's shoulder. cart is appx 100 lbs.
Housekeeping.
O-N Minerals, Cedarville Operation · 200006130 CFR 56.20003(b) · $151.00 proposed penalty
Protection of persons at switchgear.
O-N Minerals, Cedarville Operation · 200006130 CFR 56.12020 · Significant and substantial (S&S) · $1,320.00 proposed penalty
Horns and backup alarms.
O-N Minerals, Cedarville Operation · 200006130 CFR 56.14132(a) · $151.00 proposed penalty
Parking procedures for unattended equipment.
O-N Minerals, Cedarville Operation · 200006130 CFR 56.14207 · $151.00 proposed penalty
Parking procedures for unattended equipment.
O-N Minerals, Cedarville Operation · 200006130 CFR 56.14207 · $151.00 proposed penalty
Safety defects; examination, correction and records.
O-N Minerals, Cedarville Operation · 200006130 CFR 56.14100(a) · $151.00 proposed penalty
Temporary, portable containers.
O-N Minerals, Cedarville Operation · 200006130 CFR 47.44(b) · $151.00 proposed penalty
Moving machine parts.
O-N Minerals, Cedarville Operation · 200006130 CFR 56.14107(a) · Significant and substantial (S&S) · $336.00 proposed penalty
Regular Safety and Health Inspection
O-N Minerals, Cedarville Operation · 200006149.0 on-site hours reported
Insulation and fittings for power wires and cables.
O-N Minerals, Cedarville Operation · 200006130 CFR 56.12008 · $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.