Mining Incidents

Portable 45: 1 MSHA citation Metal/Non-Metal

Cornerstone Crushing LLC · Surface
Corvallis, Ravalli County, MT  ·  Temporarily Idled
MSHA Mine ID: 2402800

Portable 45 has $147 in proposed MSHA penalties and $0 outstanding across 0 contested dockets, plus health sampling and the full incident record.

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Fatalities
0
Total incidents
0
Years on record
Latest incident
Compliance record
MSHA citations since 2024
1
citations
0
significant & substantial
$147
proposed penalties
$147
paid to date
100% of proposed penalties paid to date, a $0 gap.
Source: MSHA violations data, updated weekly.
Inspection activity
MSHA inspections since 2024
1
inspections on record
7
inspection hours
n/a
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.
Rate withheld: 7 inspection hours is too few for a stable rate. A minimum of 1,000 inspection hours is required.
Source: MSHA inspections data, updated weekly.

Portable 45 has $147 in proposed MSHA penalties and $0 outstanding across 0 contested dockets.

Penalty disposition
Differences between proposed and paid penalties reflect both settlements and conference reductions and amounts still owed. Outstanding is the balance currently owed.
$147
proposed penalties
$147
current assessed
$147
paid to date
$0
outstanding
1 assessments are final orders; 0 contested dockets.
As of the most recent assessment on 2024-05-23.
Source: MSHA assessed-violations and conference/litigation data, updated weekly.
Violation severity profile
Shares are computed over citations that carry the MSHA gravity and negligence coding; a small share of records are uncoded.
0.0%
significant & substantial
0.0%
high negligence or reckless
0.0%
reasonably likely or greater
0.0%
permanently disabling or fatal if injury occurs
Negligence coding: 0.0% none, 100.0% low, 0.0% moderate, 0.0% high, 0.0% reckless.
Source: MSHA violations gravity and negligence coding, updated weekly.
Ownership history
  1. Rock It Crushing LLC 2024 to 2025
  2. Cornerstone Crushing LLC 2025 to present
Source: MSHA controller and operator history, updated weekly.
Workforce and production
Year Employees
2025 1
2024 2
Source: MSHA quarterly employment and production, updated weekly.

Portable 45 sits in Ravalli County, Montana, where the Census mining category is 1.2% of county employment.

Local economic context
County figures come from the US Census Bureau's American Community Survey, 5-year pooled estimates, so the 2023 vintage covers 2019 through 2023. The Census category is 'mining, quarrying, and oil and gas extraction', which is broader than MSHA jurisdiction and includes oil and gas workers no mine employs. These figures describe the surrounding county, not this mine, and are not a factor in any specific incident.
Ravalli County, Montana · Population 45,807
1.2%
Mining share of county employment
$71,323
Median household income
Source: US Census Bureau, American Community Survey 2023 5-year estimates.
Quarterly safety rates
Citations per million reported employee-hours. Rates begin in 2000, when MSHA's quarterly employment data starts; earlier incidents are counted but cannot be rate-adjusted. Quarters under 100,000 reported hours are greyed: too few hours for a stable rate.
Citations per million employee-hours, as reported to MSHA
Quarter Hours worked Citations S&S Per 1M hrs
2025 Q4 0 0 0
2025 Q3 62 0 0 0.0
2025 Q2 174 0 0 0.0
2024 Q4 228 0 0 0.0
2024 Q3 428 0 0 0.0
2024 Q2 194 1 0 5154.6
2024 Q1 5 0 0 0.0

No reportable incidents on file.

MSHA has no recorded reportable accidents for this mine in the current dataset. New reports appear here within a week of being filed.