Sierra Ready Mix Quarry has $84K in proposed MSHA penalties and $0 outstanding across 5 contested dockets, plus health sampling and the full incident record.
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Fatalities
1
Total incidents
2
Years on record
2021–2023
Latest incident
Sep 2023
Compliance record
MSHA citations since 2007
180
citations
40
significant & substantial
$84,099
proposed penalties
$72,862
paid to date
87% of proposed penalties paid to date, a $11,237 gap.
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.
180 citations across 1,159 inspection hours.
Source: MSHA inspections data, updated weekly.
Sierra Ready Mix Quarry has $84K in proposed MSHA penalties and $0 outstanding across 5 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.
$84K
proposed penalties
$73K
current assessed
$73K
paid to date
$0
outstanding
168 assessments are final orders; 5 contested dockets.
Of $33K in penalties contested before the Commission, $21K was upheld in final decisions.
As of the most recent assessment on 2026-06-23.
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.
Source: MSHA violations gravity and negligence coding, updated weekly.
When citations were contested
ⓘContesting a citation before the Federal Mine Safety and Health Review Commission is a lawful right. These figures state the public outcomes of that process, from MSHA's Contested Violations file.
26citations taken to the federal commission · 14% of citations on record
Settled
25 · 96%
Vacated or withdrawn
1 · 4%
88%
S&S designation survived the contest
ⓘCounts a Significant & Substantial citation as surviving when a settlement or judge's decision kept the designation, or the contest was dismissed or defaulted so the citation stands as issued. Vacated and withdrawn citations, and settlements that removed the designation, count against.
of 8 decided S&S contests · industry: 79%
36%
Penalty reduction in decided contests
$33K proposed, $21K after decisions · industry: 39%
Source: MSHA Contested Violations file (public record), updated weekly. A dismissed or defaulted contest leaves the citation standing as issued; a vacated or withdrawn citation is removed from the violation record. Latest contest filed 2023-11-20.
Contested penalties
ⓘA reduction or dismissal at the Commission is a lawful outcome of contesting a proposed penalty. Figures are the proposed amount and the amount upheld in the docket's decision.
Largest penalties this mine contested before the Federal Mine Safety and Health Review Commission, with the outcome on record.
Health sampling
ⓘA sample is a point in time compliance measurement, not an individual exposure history. These figures describe MSHA sampling records and do not establish causation or personal dose.
Metal and nonmetal contaminants (personal samples)
ⓘMany samples are screening measurements of substances with no applicable exposure limit; they are counted as samples but excluded from every over-limit figure. Over-limit shares use only limit-tested samples.
Last sampled: 2026-06-24
0%
of limit-tested samples over the exposure limit
17
samples
2
limit-tested
Most sampled contaminants
Quartz, respirable, >1% Qtz8
Respirable dust, <.1mg7
Unlisted Particulate, total, <1% Qtz1
Unlisted Particulate, respirable, <1% Qtz1
Show the individual readings (17)
Date
Contaminant
Concentration
Limit
Conc / limit
Occupation
2026-06-24
Quartz, respirable, >1% Qtz
0.15
Lab Technician
2026-06-24
Quartz, respirable, >1% Qtz
0.15
Front-end Loader Operator
2025-05-01
Quartz, respirable, >1% Qtz
0.34
1.49
0.23
Laborer, Bullgang
2025-05-01
Quartz, respirable, >1% Qtz
0.19
Laborer, Bullgang
2023-01-05
Quartz, respirable, >1% Qtz
0.29
Mechanic
2023-01-05
Respirable dust, <.1mg
0
Front-end Loader Operator
2019-09-09
Unlisted Particulate, total, <1% Qtz
2.97
Laborer, Bullgang
2019-09-09
Respirable dust, <.1mg
0
Front-end Loader Operator
2019-09-09
Quartz, respirable, >1% Qtz
0.18
Crusher Oper/Worker
2019-09-09
Quartz, respirable, >1% Qtz
0.3
Bulldozer Operator
2016-01-13
Quartz, respirable, >1% Qtz
0.2
1.79
0.11
Supervisor, Co. Official
2016-01-13
Respirable dust, <.1mg
0
Front-end Loader Operator
2013-08-27
Respirable dust, <.1mg
0
Front-end Loader Operator
2013-08-27
Unlisted Particulate, respirable, <1% Qtz
0.21
Washer Operator
2013-08-27
Respirable dust, <.1mg
0
Bulldozer Operator
2010-03-04
Respirable dust, <.1mg
0
Front-end Loader Operator
2010-03-04
Respirable dust, <.1mg
0
Washer Operator
Area samples (mill and shop air)
Last sampled: 2017-07-11, 9 years ago
2
samples
Show the individual readings (2)
Date
Contaminant
Concentration
Limit
Conc / limit
Area sampled
2017-07-11
Fibers, >5um
0
SF ORE TRANSFER
2016-01-12
Fibers, >5um
0
SF ORE TRANSFER
Source: MSHA respirable dust, quartz, and noise sampling records, updated weekly. Metal/nonmetal contaminant figures come from MSHA's Personal Health Samples and Area Samples files (public record), updated weekly.
Sierra Ready Mix Quarry recorded 0.00 reportable injury cases per 100 full-time workers in 2025.
Injury rate, 2025
ⓘThis rate is reportable injury cases per 100 full-time-equivalent workers per year, computed as 200,000 times cases divided by MSHA operator-reported employee-hours. Cases are injuries MSHA graded degree 01 through 07; accident-only events that hurt no one are excluded, and so are contractor injuries, whose hours do not attach to a single mine. Rates begin in 2000, when quarterly employment reporting starts, and are withheld below 20,000 hours in a year.
0.00
total case rate
0.00
days-away rate
0.000
fatality rate
Below average. The US metal and nonmetal mining average was 1.65 and the all-US-mining average was 1.97 cases per 100 workers.
In Nevada, metal and nonmetal mining averaged 1.25 cases per 100 workers that year.
Under 100,000 employee-hours were reported that year, so a single case moves the rate by two or more. Read the figure as approximate.
Year
total case rate
days-away
fatal
2025 *
0.00
0.00
0.000
2024 *
0.00
0.00
0.000
2023 *
7.84
0.00
0.000
2022 *
0.00
0.00
0.000
2020 *
0.00
0.00
0.000
2019 *
0.00
0.00
0.000
2018 *
0.00
0.00
0.000
* Fewer than 100,000 employee-hours that year; the rate is less stable.
Source: injury cases from MSHA accident and injury records; employee-hours from MSHA quarterly employment reports. Rate is cases per 100 full-time-equivalent workers, operator employees only.
Source: MSHA controller and operator history, updated weekly.
Workforce and production
Year
Employees
2026
15
2025
14
2024
18
2023
6
2022
7
2021
6
2020
7
2019
9
2018
9
2017
7
2016
5
2015
6
2014
6
2013
5
2012
5
2011
5
2010
4
2009
5
2008
5
2007
5
2006
4
Source: MSHA quarterly employment and production, updated weekly.
Sierra Ready Mix Quarry sits in Clark County, Nevada, where the Census mining category is 0.2% 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.
Clark County, Nevada · Population 2,293,764
0.2%
Mining share of county employment
$73,845
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
The employee was last seen on top of the tower and determined to be missing. The employee was found in a pipe traveling from the cyclone discharge box to the thickener tank. Investigation has revealed that the employee traveled outside the provided safe access to the cyclone discharge box. It is not yet determined how the employee entered the pipe.
Sierra Ready Mix · Fall to lower level, (Not Elsewhere Classified)
EE was using marking paint to create a new berm that runs along the high wall. As the employee was marking the area along the high wall, this is when the EE fell from the high wall approximately 14 feet from the top of the high wall to the point where the EE laid at rest at the bottom of the high wall.