Retrofit/Rebuild Requirements for 1993 and Earlier Model Year Urban Buses; Public Review of a Notification of Intent To Certify Equipment

Résumé

The Agency has received a request to amend a notification of intent to certify urban bus retrofit/rebuild equipment pursuant to 40 CFR part 85, subpart O from the Engelhard Corporation (Engelhard). On March 20, 1998 (63 FR 13660) EPA certified a Engelhard retrofit catalytic muffler which demonstrated a 25% reduction in particulate matter (PM) for 1992-1993 Cummins L-10 electronically-controlled (EC) petroleum-fueled diesel engines (that are not originally equipped with aftertreatment devices). In the original notification dated October 18, 1996, Engelhard requested approval for all Cummins L-10 engines manufactured prior to and including 1993. However, EPA noted in the March Federal Register document that, based on the test engine, certification could only apply to 1992-1993 L-10 EC (electronically controlled) models. EPA stated that should Engelhard provide additional information requesting to extend this certification to additional models, EPA would provide the opportunity for public comment. EPA has since received such information from Engelhard, and Engelhard is requesting that certification be extended to include all pre-1994 Cummins L-10 engines and all other 4-stroke urban b