Supplemental Environmental Projects (SEP) Back To All Programs Supplemental Environmental Projects (SEP)AboutNewsResources Policy & AuditApplicantsLists & ReportsInformación en Español Subscribe Primary Contact Supplemental Environmental Project (SEP) Email sep@arb.ca.gov Phone (279) 216-0965 Categories Topics Enforcement Division Enforcement Division News Sep 9, 2020 CARB targets heavy-duty diesel vehicle noncompliance in the Imperial Valley