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Superior - Twin Oaks Metal/Non-Metal

Superior Ready Mix Concrete L.P. · Surface

Controlled by Vulcan Materials Company

San Marcos, San Diego County, CA · Active

MSHA Mine ID: 0405514

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Email me when a new MSHA incident is filed at Superior - Twin Oaks.

Fatalities: 0
Total incidents: 8
Years on record: 2005–2025
Latest incident: Apr 2025

Compliance record

MSHA citations since 2002

194

citations

significant & substantial

$65,552

proposed penalties

$45,269

paid to date

Source: MSHA violations data, updated weekly.

Quarterly safety rates

Citations per million employee-hours, as reported to MSHA

Quarter	Hours worked	Citations	S&S	Per 1M hrs
2025 Q4	3,604	0	0	0.0
2025 Q3	4,976	0	0	0.0
2025 Q2	6,576	5	1	760.3
2025 Q1	6,020	1	0	166.1
2024 Q4	6,639	0	0	0.0
2024 Q3	6,209	0	0	0.0
2024 Q2	6,572	0	0	0.0
2024 Q1	6,360	0	0	0.0

Quarters under 100,000 reported hours are greyed: too few hours for a stable rate.

No fatalities recorded at this mine.

Reportable incidents

8 on file

2025 · 1 incident

April 25, 2025 CA · Metal/Non-Metal maintenance man, mechanic, repair/serviceman, boilermaker, fueler, tire tech, field service tech HANDLING OF MATERIALS

Superior Ready Mix Concrete L.P. · Over-exertion in lifting objects

On 6/17/25 employee provided a modified duty work status report from their personal doctor dated 6/12/25. On 4/25/25 employee reported a first aid from pain to their right arm while placing a wear liner into position. Employee self procured medical treatment, was diagnosed with a ruptured bicep, and restricted duty is being accommodated.

2024 · 1 incident

November 21, 2024 CA · Metal/Non-Metal front-end loader, scraper-loader operator, pan operator, payloader, scraper rig operator SLIP OR FALL OF PERSON

Superior Ready Mix Concrete L.P. · Fall from machine

Employee was getting on the loader and missed a step, falling backwards on their right arm/wrist.

2022 · 1 incident

July 1, 2022 CA · Metal/Non-Metal laborer, blacksmith, bull gang, parts runner, roustabout, pick-up man, pitman SLIP OR FALL OF PERSON

Superior Ready Mix Concrete L.P. · Fall from ladders

Employee fell off ladder and injured finger

2021 · 1 incident

December 30, 2021 CA · Metal/Non-Metal laborer, blacksmith, bull gang, parts runner, roustabout, pick-up man, pitman SLIP OR FALL OF PERSON

Superior Ready Mix Concrete L.P. · Fall from machine

Employee slipped and fell climbing from ladder to the cone crusher, injuring lower back.

2009 · 1 incident

August 18, 2009 CA · Metal/Non-Metal warehouseman, bagger, palletizer/stacker, store keeper, packager, fabricator, cleaning plant operator SLIP OR FALL OF PERSON

Wyroc Inc · Over-exertion (Not Elsewhere Classified)

Employee was standing and stepped to the side and twisted his knee

2007 · 1 incident

February 6, 2007 CA · Metal/Non-Metal front-end loader, scraper-loader operator, pan operator, payloader, scraper rig operator POWERED HAULAGE

Wyroc Inc · Over-exertion (Not Elsewhere Classified)

sprain of hip and thigh due to normal activity, repetitive application of break on loader.

2006 · 1 incident

July 20, 2006 CA · Metal/Non-Metal maintenance man, mechanic, repair/serviceman, boilermaker, fueler, tire tech, field service tech SLIP OR FALL OF PERSON

Wyroc Inc · Over-exertion (Not Elsewhere Classified)

Uneven ground at base of ladder, employee stepped into a pothole.

2005 · 1 incident

May 17, 2005 CA · Metal/Non-Metal laborer, blacksmith, bull gang, parts runner, roustabout, pick-up man, pitman HANDTOOLS (NONPOWERED)

Wyroc Inc · Struck by... (Not Elsewhere Classified)

Employee was operating plant. A rock became lodged in a conveyor belt. Employee used a pry bar and hammer to dislodge rock. Hammer struck pry bar, pry bar struck employee's finger.