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O-N Minerals (Chemstone Company) operator

Controlled by Carmeuse Holding SA
MSHA operator ID: L16758
Fatalities
2
Total incidents
196
Mines on record
9
Years on record
1998–2026
Compliance record
MSHA citations since 2000
1,193
citations
271
significant & substantial
$585,268
proposed penalties
$456,404
paid to date
78% of proposed penalties paid to date, a $128,864 gap.
Source: MSHA violations data, updated weekly.
Inspection activity
MSHA inspections since 2000
650
inspections on record
18,522
inspection hours
6.4
citations per 100 inspection hours
ⓘ This rate is recorded citations divided by MSHA inspection hours, per 100 hours. It reflects inspection effort, not mine size or production.
1,193 citations across 18,522 inspection hours.
Source: MSHA inspections data, updated weekly.
Penalty disposition
ⓘ Differences between proposed and paid penalties reflect both settlements and conference reductions and amounts still owed. Outstanding is the balance currently owed.
$581K
proposed penalties
$454K
current assessed
$453K
paid to date
$517
outstanding
1,176 assessments are final orders; 18 contested dockets.
As of the most recent assessment on 2026-03-25.
Source: MSHA assessed-violations and conference/litigation data, updated weekly.

Top causes

Incident timeline

2026
1
2025
1
2024
2
2023
4
2022
3
2021
8
2020
7 (1f)
2019
6
2018
7
2017
6
2016
15
2015
10
2014
10
2013
3
2012
9
2011
6
2010
4
2009
7
2008
4
2007
11
2006
10
2005
10
2004
12
2003
6
2002
8
2001
1
2000
10 (1f)
1999
13
1998
2

Mines on record

Fatalities under this operator

2 recorded
July 24, 2020 GA · Metal/Non-Metal miner, nec Fatality · MACHINERY
Carmeuse L&S · Caught in, under or between a moving and a stationary object

While loading a face on level 3, NW2, the man basket of the powder truck raised up into the roof of the mine causing a fatal incident. The accident is still under investigation by the operator and the Mine Safety and Health Administration.

January 26, 2000 VA · Metal/Non-Metal laborer, blacksmith, bull gang, parts runner, roustabout, pick-up man, pitman Fatality · POWERED HAULAGE
O-N Minerals (Chemstone Company) · Caught in, under or between a moving and a stationary object

EMPLOYEE WAS ATTEMPTING TO REMOVE STONE BUILDUP FROM UNDER SHAFT KILN CARRIAGE COUNTER WEIGHT. HE CLIMBED OVER A GUARD INTO RESTRICTED AREA WHERE THE WEIGHT WAS LOCATED ONLY INCHES OVER HIS HE AD. THE WEIGHT MADE ITS SCHEDULED DESCENT AND EE WAS TRAPPED UNDER IT.

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