Yosemite Slate Quarry Metal/Non-Metal

Mariposa Yosemite Slate Quarry · Surface

Controlled by David R Butler

mariposa, Mariposa County, CA · Intermittent

MSHA Mine ID: 0400357

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Compliance record

MSHA citations since 2001

citations

significant & substantial

$2,552

proposed penalties

$2,199

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	Per 1M hrs
2025 Q4	4	0	0.0
2025 Q3	12	0	0.0
2025 Q2	16	0	0.0
2025 Q1	16	0	0.0
2024 Q4	11	0	0.0
2024 Q3	13	0	0.0
2024 Q2	26	4	153846.2
2024 Q1	0	0

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

No fatalities recorded at this mine.

1 on file

January 20, 2006 CA · Metal/Non-Metal laborer, blacksmith, bull gang, parts runner, roustabout, pick-up man, pitman HANDLING OF MATERIALS

Mariposa Flagstone Company · Caught in, under or between (Not Elsewhere Classified)

At 11 am EE rolled a rock on his right finger rt smashed the tip. Did not lose nail went to dr. and put in finger split.