Coorstek

• Plant closing notice effective OCT 13, 2019 · 268 employees · filed AUG 20, 2019 · Closure Permanent — this notice is why the plant is listed as reported closed

Notices filed with the state under the federal WARN Act, as the state publishes them, collected by the WARN Act notices feed (CC BY 4.0). A notice records what the employer told the state; it is not by itself proof that the plant closed.

What they make

Where it is

Other plants nearby

Every listed plant in Ventura County

Also at this address

No other federal record shares this street address.

Where this record comes from

2 sources hold this plant, and 7 fields on this page come from them. Each line is one agency’s own record of it: the identifier it is filed under, whether that record shows the plant operating or only that it exists, and when the register first and last saw it there.

EPA cross-references this facility in BR, CA-CERS, CA-ENVIROVIEW, HWTS-DATAMART, NPDES, OSHA-OIS, RCRAINFO, TRIS · EPA site type STATIONARY.

• State WARN plant-closing and layoff noticesCLOSURE
  first seen OCT 2019 · last seen OCT 2019
• EPA Facility Registry ServiceEXISTENCE
  Record 110041968920 · first seen DEC 2015 · last seen DEC 2015

IN VENTURA COUNTY2 other plants share this one’s industry (Clay Product and Refractory Manufacturing, NAICS 3271); 0 of them have a size band on record.

What each source says

Every field below, as each source filed it. The value this page shows is marked; where the sources disagree, the field says so. Status is computed from independent sources; nothing here is self-reported unless marked Claimed.

Name

EPA: COORSTEK · NOV 2026

Street address

EPA: 4544 MCGRATH ST · NOV 2026

City

EPA: VENTURA · NOV 2026

State

EPA: CA · NOV 2026

County (FIPS code)

EPA: 06111 · NOV 2026

Coordinates

EPA: 34.25449,-119.23094 · NOV 2026

Hazardous waste generator (RCRA)

EPA ECHO: SQG · NOV 2026