Key Takeaway

El Cajon Quarry is a active surface mine producing Stone, located in San Diego, San Diego County, CA. It has 131 violations on record (43 S&S) and $68K in proposed penalties. Operated by Robertson's Ready Mix Ltd.

El Cajon Quarry

Active Surface Stone

Operator: Robertson's Ready Mix Ltd

Controller: RRM Development Corporation; Mitsubishi Corp

Location: San Diego, San Diego County, CA

Employees: 5

131
Violations
43
S&S Violations
18
Accidents
$68K
Penalties

Recent Violations

View all 131 →
Date Section S&S Negligence Penalty
02/10/2026 47.41(a) Non-S&S ModNegligence $0
02/10/2026 56.15004 S&S ModNegligence $0
04/03/2025 46.7(a) Non-S&S LowNegligence $168
03/06/2025 56.12004 Non-S&S LowNegligence $151
03/06/2025 56.11012 S&S ModNegligence $226
03/06/2025 56.12032 Non-S&S ModNegligence $151
03/06/2025 56.14207 Non-S&S LowNegligence $151
03/06/2025 56.14100(a) S&S LowNegligence $336
03/06/2025 56.12002 Non-S&S ModNegligence $151
03/06/2025 56.14112(b) Non-S&S LowNegligence $151
05/01/2024 56.20003(a) Non-S&S ModNegligence $147
01/31/2024 56.20003(a) S&S ModNegligence $1,287
01/31/2024 56.20014 Non-S&S LowNegligence $147
07/19/2023 56.12008 Non-S&S LowNegligence $155
07/19/2023 56.18002(a) Non-S&S HighNegligence $12,684
07/18/2023 56.12004 Non-S&S LowNegligence $155
07/18/2023 56.11001 S&S LowNegligence $518
03/14/2023 56.12004 Non-S&S LowNegligence $143
03/14/2023 56.14112(a)(1) S&S LowNegligence $143
03/14/2023 56.14112(b) S&S LowNegligence $295

Accidents & Injuries

View all 18 →
Date Classification Injury Days Lost
05/14/2024 HANDLING OF MATERIALS DYS AWY FRM WRK & RESTRCTD ACT 1d lost, 8d restricted
01/20/2024 HANDTOOLS (NONPOWERED) NO DYS AWY FRM WRK,NO RSTR ACT None
02/16/2023 DISORDERS (REPEATED TRAUMA) OCCUPATNAL ILLNESS NOT DEG 1-6 None
04/18/2022 MACHINERY DAYS AWAY FROM WORK ONLY 1d lost
02/14/2022 STEPPING OR KNEELING ON OBJECT DAYS RESTRICTED ACTIVITY ONLY 6d restricted
12/07/2021 SLIP OR FALL OF PERSON DAYS AWAY FROM WORK ONLY 5d lost
09/24/2021 HANDTOOLS (NONPOWERED) DAYS AWAY FROM WORK ONLY None
07/31/2021 HANDTOOLS (NONPOWERED) DYS AWY FRM WRK & RESTRCTD ACT 2d lost, 9d restricted
03/11/2021 HANDLING OF MATERIALS DYS AWY FRM WRK & RESTRCTD ACT 50d lost, 93d restricted
12/28/2020 SLIP OR FALL OF PERSON NO DYS AWY FRM WRK,NO RSTR ACT None

Inspections

View all 80 →
Begin End Hours Inspectors
02/09/2026 02/10/2026 17.75 1
04/03/2025 04/03/2025 10.50 1
03/05/2025 03/07/2025 41.50 1
04/30/2024 05/02/2024 27.50 1
01/31/2024 02/01/2024 17.00 1
07/19/2023 07/19/2023 0.75 1
07/17/2023 07/19/2023 26.25 1
03/13/2023 03/15/2023 20.50 1
09/13/2022 09/14/2022 15.75 1
08/09/2022 08/10/2022 13.25 1

Mine Details

MSHA Mine ID0400133
Mine TypeSurface
StatusActive
CommodityStone
SIC DescriptionCrushed, Broken Granite
Employees5
Days/Week5.0
Hours/Shift10.0
Coordinates32.7647220, -116.8900000
Nearest TownSan Diego

Frequently Asked Questions

How many MSHA violations does El Cajon Quarry have?

El Cajon Quarry has 131 MSHA violations on record, of which 43 are classified as Significant & Substantial (S&S). Total proposed penalties amount to $68K.

What type of mine is El Cajon Quarry?

El Cajon Quarry is a Surface mine producing Stone, located in San Diego, San Diego County, CA. It currently has 5 employees.

Has anyone been injured or killed at El Cajon Quarry?

According to MSHA records, El Cajon Quarry has 18 reported accident/injury records and 0 fatalities on file.

Who operates El Cajon Quarry?

El Cajon Quarry is operated by Robertson's Ready Mix Ltd and controlled by RRM Development Corporation; Mitsubishi Corp. MSHA Mine ID: 0400133.