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Rio Medina: 159 MSHA citations Metal/Non-Metal

San Antonio, Medina County, TX  ·  Active
MSHA Mine ID: 4103594

Rio Medina has $51K in proposed MSHA penalties and $0 outstanding across 5 contested dockets, plus health sampling and the full incident record.

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Fatalities
0
Total incidents
7
Years on record
1992–2024
Latest incident
Apr 2024
Compliance record
MSHA citations since 2000
159
citations
38
significant & substantial
$50,872
proposed penalties
$50,501
paid to date
99% of proposed penalties paid to date, a $371 gap.
Source: MSHA violations data, updated weekly.
See Martin Marietta Materials Southwest LLC's full MSHA compliance history →
Inspection activity
MSHA inspections since 2000
67
inspections on record
869
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: 869 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: 2015-05-18.
On record since 2015.
Source: MSHA imminent-danger order records, updated weekly.

Rio Medina has $51K 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.
$51K
proposed penalties
$51K
current assessed
$51K
paid to date
$0
outstanding
156 assessments are final orders; 5 contested dockets.
Of $14K in penalties contested before the Commission, $14K was upheld in final decisions.
As of the most recent assessment on 2026-05-18.
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.
24.4%
significant & substantial
8.3%
high negligence or reckless
25.0%
reasonably likely or greater
44.9%
permanently disabling or fatal if injury occurs
Negligence coding: 0.0% none, 4.5% low, 87.2% moderate, 8.3% high, 0.0% reckless.
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.
15 citations taken to the federal commission · 9% of citations on record
  • Settled 1 · 7%
  • Stood as issued 12 · 80%
  • Vacated or withdrawn 2 · 13%
100%
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 5 decided S&S contests · industry: 79%
3%
Penalty reduction in decided contests
$14K proposed, $14K 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 2017-07-30.
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.
Docket Decision Judge Year Proposed / upheld
CENT 2010-1206M Dismissal Rae 2015 $11K → $11K
CENT 2010-1205M Dismissal Rae 2015 $3K → $3K
CENT 2012-893M Settlement Lesnick 2013 $262 → $100
CENT 2017-0440 Withdrawal Lesnick 2017 $116 → $0
CENT 2012-551M Dismissal Lesnick 2012 $100 → $0
Source: FMSHRC civil penalty dockets and decisions (public record), 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: 2023-07-10, 3 years ago
0%
of limit-tested samples over the exposure limit
17
samples
10
limit-tested
Most sampled contaminants
  • Nuisance dust, respirable, <1% Qtz8
  • Respirable dust, <.1mg7
  • Quartz, respirable, >1% Qtz2
Show the individual readings (17)
Date Contaminant Concentration Limit Conc / limit Occupation
2023-07-10 Nuisance dust, respirable, <1% Qtz 0.41 10 0.04 Laborer, Bullgang
2023-07-10 Nuisance dust, respirable, <1% Qtz 0.15 10 0.02 Laborer, Bullgang
2018-06-05 Nuisance dust, respirable, <1% Qtz 0.28 10 0.03 Dry Screen Plant Operator
2018-06-05 Respirable dust, <.1mg 0 Truck Driver
2018-06-05 Nuisance dust, respirable, <1% Qtz 0.67 10 0.07 Laborer, Bullgang
2018-06-05 Respirable dust, <.1mg 0 Front-end Loader Operator
2012-11-20 Nuisance dust, respirable, <1% Qtz 0.21 10 0.02 Crusher Oper/Worker
2012-11-20 Nuisance dust, respirable, <1% Qtz 0.19 10 0.02 Truck Driver
2012-11-20 Respirable dust, <.1mg 0 Crusher Oper/Worker
2009-09-09 Respirable dust, <.1mg 0 Front-end Loader Operator
2009-09-09 Respirable dust, <.1mg 0 Cleanup Man
2009-09-09 Respirable dust, <.1mg 0 Front-end Loader Operator
2003-10-30 Respirable dust, <.1mg 0 Front-end Loader Operator
2003-10-30 Quartz, respirable, >1% Qtz 0.45 2.56 0.18 Front-end Loader Operator
2003-10-30 Nuisance dust, respirable, <1% Qtz 0.25 10 0.03 Dry Screen Plant Operator
2003-10-30 Quartz, respirable, >1% Qtz 0.41 2.63 0.16 Crusher Oper/Worker
2003-10-30 Nuisance dust, respirable, <1% Qtz 0.44 10 0.04 Truck Driver
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.

Rio Medina 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 Texas, metal and nonmetal mining averaged 1.17 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 * 4.07 0.00 0.000
2023 * 6.26 0.00 0.000
2022 * 3.28 0.00 0.000
2021 * 0.00 0.00 0.000
2020 * 0.00 0.00 0.000
2019 * 3.36 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.
Ownership history
  1. Medina Crushed Stone Inc. 1990 to 2011
  2. Martin Marietta Materials Southwest LLC 2011 to present
Source: MSHA controller and operator history, updated weekly.
Workforce and production
Year Employees
2026 21
2025 20
2024 21
2023 24
2022 23
2021 23
2020 22
2019 23
2018 21
2017 23
2016 22
2015 21
2014 20
2013 17
2012 8
2011 10
2010 36
2009 36
2008 41
2007 40
2006 34
2005 26
2004 24
2003 22
2002 17
2001 16
2000 19
Source: MSHA quarterly employment and production, updated weekly.

Rio Medina sits in Medina County, Texas, where the Census mining category is 3.1% 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.
Medina County, Texas · Population 52,419
3.1%
Mining share of county employment
$73,462
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 11,382 1 0 87.9
2026 Q1 11,865 0 0 0.0
2025 Q4 9,867 5 0 506.7
2025 Q3 9,992 0 0 0.0
2025 Q2 12,920 0 0 0.0
2025 Q1 11,238 0 0 0.0
2024 Q4 11,278 2 0 177.3
2024 Q3 11,193 1 0 89.3
Show 96 earlier quarters
Quarter Hours worked Citations S&S Per 1M hrs
2024 Q2 13,482 0 0 0.0
2024 Q1 13,131 0 0 0.0
2023 Q4 14,993 0 0 0.0
2023 Q3 16,840 5 2 296.9
2023 Q2 16,122 0 0 0.0
2023 Q1 15,956 0 0 0.0
2022 Q4 14,945 0 0 0.0
2022 Q3 15,975 2 1 125.2
2022 Q2 15,052 0 0 0.0
2022 Q1 14,957 0 0 0.0
2021 Q4 16,511 0 0 0.0
2021 Q3 15,726 1 0 63.6
2021 Q2 12,892 0 0 0.0
2021 Q1 11,507 1 1 86.9
2020 Q4 14,091 0 0 0.0
2020 Q3 13,088 0 0 0.0
2020 Q2 13,822 1 0 72.3
2020 Q1 16,051 0 0 0.0
2019 Q4 15,973 1 0 62.6
2019 Q3 15,334 1 0 65.2
2019 Q2 13,703 0 0 0.0
2019 Q1 14,567 1 0 68.6
2018 Q4 14,700 0 0 0.0
2018 Q3 14,157 0 0 0.0
2018 Q2 14,753 4 1 271.1
2018 Q1 14,724 1 0 67.9
2017 Q4 14,820 0 0 0.0
2017 Q3 16,901 0 0 0.0
2017 Q2 15,984 3 0 187.7
2017 Q1 15,919 0 0 0.0
2016 Q4 17,352 0 0 0.0
2016 Q3 17,961 0 0 0.0
2016 Q2 17,003 2 0 117.6
2016 Q1 14,590 0 0 0.0
2015 Q4 18,373 1 0 54.4
2015 Q3 17,008 0 0 0.0
2015 Q2 17,323 1 0 57.7
2015 Q1 16,094 0 0 0.0
2014 Q4 14,705 2 2 136.0
2014 Q3 14,915 5 1 335.2
2014 Q2 15,731 0 0 0.0
2014 Q1 12,876 2 0 155.3
2013 Q4 15,083 0 0 0.0
2013 Q3 15,077 0 0 0.0
2013 Q2 12,888 0 0 0.0
2013 Q1 12,661 0 0 0.0
2012 Q4 13,191 5 1 379.0
2012 Q3 14,332 0 0 0.0
2012 Q2 6,252 3 0 479.8
2012 Q1 5,238 0 0 0.0
2011 Q4 4,616 0 0 0.0
2011 Q3 2,583 0 0 0.0
2011 Q2 9 0 0 0.0
2011 Q1 16,005 2 0 125.0
2010 Q4 16,890 0 0 0.0
2010 Q3 15,911 0 0 0.0
2010 Q2 14,577 4 2 274.4
2010 Q1 13,754 7 2 508.9
2009 Q4 18,964 0 0 0.0
2009 Q3 18,305 0 0 0.0
2009 Q2 19,452 6 4 308.5
2009 Q1 15,471 10 2 646.4
2008 Q4 21,107 0 0 0.0
2008 Q3 20,537 0 0 0.0
2008 Q2 23,489 13 3 553.5
2008 Q1 21,881 4 1 182.8
2007 Q4 22,283 0 0 0.0
2007 Q3 20,773 0 0 0.0
2007 Q2 18,017 7 0 388.5
2007 Q1 27,484 0 0 0.0
2006 Q4 19,851 0 0 0.0
2006 Q3 19,317 3 0 155.3
2006 Q2 16,796 0 0 0.0
2006 Q1 16,940 5 1 295.2
2005 Q4 15,657 0 0 0.0
2005 Q3 15,712 0 0 0.0
2005 Q2 14,661 2 0 136.4
2005 Q1 13,201 0 0 0.0
2004 Q4 15,573 0 0 0.0
2004 Q3 13,522 0 0 0.0
2004 Q2 15,016 1 1 66.6
2004 Q1 10,784 4 2 370.9
2003 Q4 15,025 6 4 399.3
2003 Q3 11,809 0 0 0.0
2003 Q2 10,825 0 0 0.0
2003 Q1 9,609 0 0 0.0
2002 Q4 9,256 0 0 0.0
2002 Q3 9,937 1 0 100.6
2002 Q2 10,821 0 0 0.0
2002 Q1 9,946 1 1 100.5
2001 Q4 10,977 0 0 0.0
2001 Q3 10,049 2 0 199.0
2001 Q2 8,009 12 1 1498.3
2001 Q1 7,109 0 0 0.0
2000 Q3 8,860 0 0 0.0
2000 Q1 10,104 0 0 0.0
No fatalities recorded at this mine.

Reportable incidents

7 on file

2024 · 1 incident

April 12, 2024 TX · Metal/Non-Metal maintenance man, mechanic, repair/serviceman, boilermaker, fueler, tire tech, field service tech HANDLING OF MATERIALS
Martin Marietta Materials Southwest LLC · Caught in, under or between a moving and a stationary object

EE was moving a large rock, rock slipped, EE moved to grab it and EE's thumb was smashed between the rock and loader frame. EE received a fracture to tip of right thumb and received 7 stitches.

2023 · 2 incidents

July 10, 2023 TX · Metal/Non-Metal warehouseman, bagger, palletizer/stacker, store keeper, packager, fabricator, cleaning plant operator HANDLING OF MATERIALS
Martin Marietta Materials Southwest LLC · Over-exertion in lifting objects

EE was moving rock from choked crusher. Rock was in front of EE and EE tried to adjust it. EE heard shoulder pop and then felt intense pain.

February 9, 2023 TX · Metal/Non-Metal maintenance man, mechanic, repair/serviceman, boilermaker, fueler, tire tech, field service tech MACHINERY
Martin Marietta Materials Southwest LLC · Struck by... (Not Elsewhere Classified)

EE was holding counter sunk bolt up in position while using impact to loosen nut, impact caused bolt to turn cutting palm of EE left hand.

2022 · 1 incident

2019 · 1 incident

October 11, 2019 TX · Metal/Non-Metal miner, prospector, nec HANDLING OF MATERIALS
Martin Marietta Materials Southwest LLC · Caught in, under or between a moving and a stationary object

EE1 opened clogged crusher, entered and began removing larger rocks through the crusher door. EE2 was on the platform outside moving rocks from the door over the edge of the platform to the ground. A rock shifted and pinched EE2 finger against the steel crusher door.

2005 · 1 incident

November 10, 2005 TX · Metal/Non-Metal maintenance man, mechanic, repair/serviceman, boilermaker, fueler, tire tech, field service tech HANDTOOLS (NONPOWERED)
Medina Crushed Stone Inc. · Struck by... (Not Elsewhere Classified)

Employee was holding a hammer pin when another employee was driving the pin in with a sledge hammer. The co-worker missed the pin and struck injured on the hand with hammer.

1992 · 1 incident

September 22, 1992 TX · Metal/Non-Metal mine manager, mine foreman, mine owner EXPLOSIVES AND BREAKING AGENTS
Medina Crushed Stone Inc. · Struck by falling object

I WAS SEEKING PROTECTION FROM THE FLY ROCKS BEHIND A ROCK LEDGE,I SET OFF THE BLAST THE VIBRATION CRACKED THE LEDGE ABOVE ME AND A PIECE OF THE LEDGE FELL,FROM ABOUT A FOOT ABOVE AND FELL ON T HE LEFT SIDE OF MY BACK AND SLID OFF GRAISING MYBACK.INJURIES RECEIVED FRACTURED PELVIS,4 FRACTURED RIBS,TORN BLADDER.THERE IS NOT PERMANENT INJURY OR DISABILITIES.