The Indiana Department of Environmental Management has canceled a public hearing on a revision to a plan related to a variance issued for a BP Whiting refinery air permit.

"The hearing was canceled because we saw there is a potential that folks would think it was on the air permit application for the refinery's expansion project," IDEM spokeswoman Amy Hartsock said Wednesday. "That permit application is under review and this meeting is not about that."

BP is seeking a modification to its air permit for its proposed $3.8 billion expansion. However, the draft air permit for the expansion project has not been published, therefore no public hearing date for it has been scheduled.

IDEM will provide a 30-day notice for that public hearing, Hartsock said.

The public hearing for changes to the State Implementation Plan had been set for 1 p.m. Aug. 9 at IDEM's Merrillville office. It has not been rescheduled.

BP required the variance to the refinery's air permit because there have been updates in federal regulations since BP received the permit in 1998.

"The changes have to do with the method to calculate their emissions that are not reflected in its air permits," Hartsock said. "BP asked for variance so their updates could be incorporated into their requirements."

The order enforcing BP's one-year air permit variance was issued by IDEM Commissioner Thomas Easterly on July 5.

"IDEM reviewed the modeling analysis for the revised emission limits, including the emission units that are shut down or decreasing the emission limit as part of the requested SIP revision," Easterly states in his written decision to approve the permit.

"IDEM has determined that the requested limits will still demonstrate attainment of the PM10 (particulate matter) NAAQS (National Ambient Air Quality Standards) and the variance will not result in environmental harm to air quality in Lake County," he says.