Key Takeaway

Hidden Canyon Quarry is a active surface mine producing SandAndGravel, located in Greenfield, Monterey County, CA. It has 240 violations on record (69 S&S) and $253K in proposed penalties. Operated by San Benito Supply.

Hidden Canyon Quarry

Active Surface SandAndGravel

Operator: San Benito Supply

Controller: Mark Schipper; Peter Schipper

Location: Greenfield, Monterey County, CA

Employees: 5

240
Violations
69
S&S Violations
13
Accidents
$253K
Penalties

Recent Violations

View all 240 →
Date Section S&S Negligence Penalty
01/13/2026 56.14112(a)(1) Non-S&S LowNegligence $151
01/12/2026 56.14100(b) Non-S&S LowNegligence $151
06/05/2025 56.20003(b) S&S ModNegligence $1,219
06/04/2025 56.11027 Non-S&S ModNegligence $2,312
06/04/2025 56.14107(a) Non-S&S ModNegligence $7,676
06/04/2025 56.20003(a) Non-S&S ModNegligence $209
06/04/2025 56.11012 Non-S&S ModNegligence $209
06/04/2025 56.14101(a)(2) Non-S&S ModNegligence $209
06/04/2025 56.14100(b) Non-S&S ModNegligence $209
06/04/2025 56.5001(a)/.5005 S&S ModNegligence $1,550
11/13/2024 56.11001 Non-S&S ModNegligence $147
11/13/2024 56.4201 Non-S&S ModNegligence $147
07/16/2024 56.12004 Non-S&S ModNegligence $147
07/16/2024 56.14107(a) Non-S&S ModNegligence $147
07/16/2024 56.14107(a) S&S ModNegligence $204
07/16/2024 56.14107(a) Non-S&S ModNegligence $147
07/16/2024 56.4201(a)(2) Non-S&S ModNegligence $147
07/16/2024 56.14100(b) S&S ModNegligence $453
07/16/2024 56.14132(a) S&S HighNegligence $1,511
07/16/2024 56.12041 Non-S&S ModNegligence $147

Accidents & Injuries

View all 13 →
Date Classification Injury Days Lost
10/16/2025 SLIP OR FALL OF PERSON DAYS RESTRICTED ACTIVITY ONLY 26d restricted
10/05/2023 MACHINERY DAYS AWAY FROM WORK ONLY 15d lost
03/10/2023 SLIP OR FALL OF PERSON DAYS RESTRICTED ACTIVITY ONLY 10d restricted
01/18/2023 MACHINERY NO DYS AWY FRM WRK,NO RSTR ACT None
02/23/2022 HANDLING OF MATERIALS DAYS RESTRICTED ACTIVITY ONLY 13d restricted
02/18/2022 HANDLING OF MATERIALS NO DYS AWY FRM WRK,NO RSTR ACT None
08/17/2020 HANDLING OF MATERIALS DYS AWY FRM WRK & RESTRCTD ACT None
04/30/2019 MACHINERY NO DYS AWY FRM WRK,NO RSTR ACT None
04/18/2019 SLIP OR FALL OF PERSON DYS AWY FRM WRK & RESTRCTD ACT 60d lost, 215d restricted
04/05/2019 DISORDERS (REPEATED TRAUMA) OCCUPATNAL ILLNESS NOT DEG 1-6 None

Inspections

View all 55 →
Begin End Hours Inspectors
01/12/2026 01/13/2026 23.50 1
09/02/2025 09/03/2025 20.00 1
08/05/2025 08/06/2025 12.25 1
06/23/2025 06/23/2025 6.50 1
06/09/2025 06/11/2025 5.00 1
06/04/2025 06/05/2025 25.75 1
11/14/2024 11/14/2024 8.25 1
11/13/2024 11/14/2024 13.25 1
08/05/2024 08/07/2024 2.00 1
07/15/2024 07/16/2024 15.25 1

Mine Details

MSHA Mine ID0405653
Mine TypeSurface
StatusActive
CommoditySandAndGravel
SIC DescriptionConstruction Sand and Gravel
Employees5
Days/Week5.0
Hours/Shift10.0
Coordinates36.3541670, -121.2269440
Nearest TownGreenfield

Frequently Asked Questions

How many MSHA violations does Hidden Canyon Quarry have?

Hidden Canyon Quarry has 240 MSHA violations on record, of which 69 are classified as Significant & Substantial (S&S). Total proposed penalties amount to $253K.

What type of mine is Hidden Canyon Quarry?

Hidden Canyon Quarry is a Surface mine producing SandAndGravel, located in Greenfield, Monterey County, CA. It currently has 5 employees.

Has anyone been injured or killed at Hidden Canyon Quarry?

According to MSHA records, Hidden Canyon Quarry has 13 reported accident/injury records and 0 fatalities on file.

Who operates Hidden Canyon Quarry?

Hidden Canyon Quarry is operated by San Benito Supply and controlled by Mark Schipper; Peter Schipper. MSHA Mine ID: 0405653.