Key Takeaway

Heidelberg Materials High Rock Quarry is a active surface mine producing Stone, located in Monroe, Snohomish County, WA. It has 258 violations on record (33 S&S) and $57K in proposed penalties. Operated by HM Pacific Northwest, Inc..

Heidelberg Materials High Rock Quarry

Active Surface Stone

Operator: HM Pacific Northwest, Inc.

Controller: Heidelberg Materials AG

Location: Monroe, Snohomish County, WA

Employees: 32

258
Violations
33
S&S Violations
38
Accidents
$57K
Penalties

Recent Violations

View all 258 →
Date Section S&S Negligence Penalty
01/15/2026 56.12004 Non-S&S ModNegligence $0
01/15/2026 56.12018 Non-S&S ModNegligence $0
01/15/2026 56.12002 Non-S&S LowNegligence $0
01/15/2026 56.11001 Non-S&S LowNegligence $0
01/14/2026 56.23003(b) Non-S&S ModNegligence $0
01/14/2026 46.5(a) S&S LowNegligence $0
01/13/2026 56.4402 Non-S&S ModNegligence $0
01/13/2026 56.12004 Non-S&S ModNegligence $0
01/13/2026 56.11001 S&S ModNegligence $0
10/30/2025 56.6306(e) S&S HighNegligence $1,968
07/10/2025 56.3200 S&S ModNegligence $3,184
07/10/2025 56.20003(a) S&S ModNegligence $959
07/10/2025 56.12018 Non-S&S ModNegligence $193
07/10/2025 56.12018 Non-S&S ModNegligence $193
07/09/2025 56.11002 Non-S&S ModNegligence $193
07/09/2025 56.11027 Non-S&S ModNegligence $193
07/09/2025 56.11027 Non-S&S ModNegligence $193
07/09/2025 56.14112(a)(1) Non-S&S ModNegligence $288
07/09/2025 56.14132(a) Non-S&S ModNegligence $642
07/09/2025 56.11027 Non-S&S ModNegligence $193

Accidents & Injuries

View all 38 →
Date Classification Injury Days Lost
11/07/2025 MACHINERY NO DYS AWY FRM WRK,NO RSTR ACT None
05/03/2021 MACHINERY DAYS AWAY FROM WORK ONLY 284d lost
02/04/2021 HANDTOOLS (NONPOWERED) NO DYS AWY FRM WRK,NO RSTR ACT None
04/02/2019 HANDLING OF MATERIALS NO DYS AWY FRM WRK,NO RSTR ACT None
03/22/2019 HANDLING OF MATERIALS DAYS RESTRICTED ACTIVITY ONLY 10d restricted
04/23/2018 HANDLING OF MATERIALS PERM TOT OR PERM PRTL DISABLTY None
10/27/2017 HANDTOOLS (NONPOWERED) DAYS RESTRICTED ACTIVITY ONLY 2d restricted
08/26/2016 SLIP OR FALL OF PERSON NO DYS AWY FRM WRK,NO RSTR ACT None
06/16/2015 SLIP OR FALL OF PERSON NO DYS AWY FRM WRK,NO RSTR ACT None
04/24/2015 POWERED HAULAGE NO DYS AWY FRM WRK,NO RSTR ACT None

Inspections

View all 68 →
Begin End Hours Inspectors
01/26/2026 01/26/2026 6.50 1
01/12/2026 01/16/2026 39.00 1
10/28/2025 11/04/2025 17.00 1
09/02/2025 09/03/2025 16.00 1
07/08/2025 07/15/2025 46.75 1
12/13/2024 12/16/2024 13.00 1
11/14/2024 11/26/2024 58.00 1
05/28/2024 05/30/2024 23.00 1
03/07/2024 03/13/2024 24.50 1
08/09/2023 08/09/2023 0.75 1

Mine Details

MSHA Mine ID4501999
Mine TypeSurface
StatusActive
CommodityStone
SIC DescriptionCrushed, Broken Traprock
Employees32
Days/Week6.0
Hours/Shift8.0
Coordinates47.8158330, -121.9747220
Nearest TownMonroe

Frequently Asked Questions

How many MSHA violations does Heidelberg Materials High Rock Quarry have?

Heidelberg Materials High Rock Quarry has 258 MSHA violations on record, of which 33 are classified as Significant & Substantial (S&S). Total proposed penalties amount to $57K.

What type of mine is Heidelberg Materials High Rock Quarry?

Heidelberg Materials High Rock Quarry is a Surface mine producing Stone, located in Monroe, Snohomish County, WA. It currently has 32 employees.

Has anyone been injured or killed at Heidelberg Materials High Rock Quarry?

According to MSHA records, Heidelberg Materials High Rock Quarry has 38 reported accident/injury records and 0 fatalities on file.

Who operates Heidelberg Materials High Rock Quarry?

Heidelberg Materials High Rock Quarry is operated by HM Pacific Northwest, Inc. and controlled by Heidelberg Materials AG. MSHA Mine ID: 4501999.