MSHA record for Three Sisters (mine ID 2200848). Fatalities, non-fatal incidents grouped by year, current operator and controller, and mine context.
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Fatalities
0
Total incidents
1
Years on record
2025
Latest incident
Oct 2025
Inspection activity
MSHA inspections since 2023
7
inspections on record
60
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: 60 inspection hours is too few for a stable rate. A minimum of 1,000 inspection hours is required.
Source: MSHA inspections data, updated weekly.
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: 2023-12-12
1
samples
0
limit-tested
Most sampled contaminants
Respirable dust, <.1mg1
Show the individual readings (1)
Date
Contaminant
Concentration
Limit
Conc / limit
Occupation
2023-12-12
Respirable dust, <.1mg
0
Utility Man
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.
Source: MSHA controller and operator history, updated weekly.
Workforce and production
Year
Employees
2026
10
2025
7
2024
8
2023
8
Source: MSHA quarterly employment and production, updated weekly.
Three Sisters sits in DeSoto County, Mississippi, 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.
DeSoto County, Mississippi · Population 188,598
0.2%
Mining share of county employment
$82,980
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
2026 Q2
4,801
0
0
0.0
2026 Q1
3,710
0
0
0.0
2025 Q4
4,194
0
0
0.0
2025 Q3
4,271
0
0
0.0
2025 Q2
3,615
0
0
0.0
2025 Q1
3,183
0
0
0.0
2024 Q4
3,507
0
0
0.0
2024 Q3
3,529
0
0
0.0
Show 4 earlier quartersHide earlier quarters
Quarter
Hours worked
Citations
S&S
Per 1M hrs
2024 Q2
4,940
0
0
0.0
2024 Q1
4,848
0
0
0.0
2023 Q4
3,880
0
0
0.0
2023 Q3
3,205
0
0
0.0
No fatalities recorded at this mine.
Reportable incidents
1 on file
2025 · 1 incident
October 10, 2025MS · Metal/Non-Metallaborer, blacksmith, bull gang, parts runner, roustabout, pick-up man, pitmanHANDTOOLS (NONPOWERED)
Employee was standing on a piece of metal that was being bend so it wouldn't move and with hands on the frame of the conveyor above. An employee struck the metal with a hammer causing employee # 1 to lose balance. Hand was holding on the conveyor frame which put weight on wrist (left) injuring it.
Related mines
Other mines operated by Standard Construction Company