Mojave Rock Mine has $35K in proposed MSHA penalties and $2K outstanding across 3 contested dockets, plus health sampling and the full incident record.
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Fatalities
0
Total incidents
1
Years on record
2024
Latest incident
Aug 2024
Compliance record
MSHA citations since 2019
53
citations
21
significant & substantial
$35,343
proposed penalties
$16,138
paid to date
46% of proposed penalties paid to date, a $19,205 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.
Rate withheld: 417 inspection hours is too few for a stable rate. A minimum of 1,000 inspection hours is required.
Source: MSHA inspections data, updated weekly.
Imminent-danger orders
ⓘA Section 107(a) order removes miners from an area when an inspector finds an imminent danger. Each order is lifted once the condition is corrected, so this counts orders issued, not orders now in effect.
1
Section 107(a) orders
Most recent order: 2023-10-12.
On record since 2023.
Source: MSHA imminent-danger order records, updated weekly.
Mojave Rock Mine has $35K in proposed MSHA penalties and $2K outstanding across 3 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.
$35K
proposed penalties
$18K
current assessed
$16K
paid to date
$2K
outstanding
52 assessments are final orders; 3 contested dockets.
Of $24K in penalties contested before the Commission, $7K was upheld in final decisions.
As of the most recent assessment on 2026-04-21.
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.
21citations taken to the federal commission · 40% of citations on record
Settled
21 · 100%
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%
69%
Penalty reduction in decided contests
$24K proposed, $7K 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 2026-04-01.
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: 2026-01-07
0%
of limit-tested samples over the exposure limit
7
samples
3
limit-tested
Most sampled contaminants
Respirable dust, <.1mg4
Quartz, respirable, >1% Qtz3
Show the individual readings (7)
Date
Contaminant
Concentration
Limit
Conc / limit
Occupation
2026-01-07
Respirable dust, <.1mg
0
Rotary Bucket Ex. Operator
2025-04-17
Quartz, respirable, >1% Qtz
0.18
0.87
0.21
Dry Screen Plant Operator
2023-10-11
Respirable dust, <.1mg
0
Truck Driver
2022-10-05
Quartz, respirable, >1% Qtz
0.25
0.81
0.31
Laborer, Bullgang
2021-04-23
Quartz, respirable, >1% Qtz
0.49
0.67
0.73
Laborer, Bullgang
2019-10-02
Respirable dust, <.1mg
0
Crusher Oper/Worker
2017-11-29
Respirable dust, <.1mg
0
Backhoe Operator
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.
Mojave Rock Mine 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
No reportable injury cases in any year shown. Employee-hours were reported in each of those years, so these are true zeros rather than missing data. Citations, listed in the compliance record above, are inspector-found violations and are counted separately from worker injuries.
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 California, metal and nonmetal mining averaged 1.43 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 *
0.00
0.00
0.000
2022 *
0.00
0.00
0.000
2021 *
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
11
2025
10
2024
10
2023
10
2022
9
2021
12
2020
5
2019
4
2018
2
2017
2
Source: MSHA quarterly employment and production, updated weekly.
Mojave Rock Mine sits in Kern County, California, where the Census mining category is 2.3% 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.
Kern County, California · Population 910,433
2.3%
Mining share of county employment
$67,660
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
A truck driver, that is not an employee of MRC Rock & Sand LLC, was found unresponsive after getting loaded with rock. It is determined that the driver lost consciousness due to a medical emergency. Driver was transported to the hospital and survived the event.