CHICAGO | BP violated a host of Clean Air Act violations when it modified a unit at its Whiting refinery without obtaining the proper permits, the U.S. Environmental Protection Agency alleged Friday.

EPA alleged that the BP Whiting refinery, located at 2815 Indianapolis Blvd., failed to obtain a permit when it made major modifications to its fluidized catalytic cracking unit. The unpermitted modification caused significant increases of nitrogen oxide, sulfur dioxide, particulate matter and carbon monoxide emissions, according to the EPA.

The refinery also allegedly violated new source performance standards by modifying flares without complying with requirements, exceeding sulfur dioxide emission limits and failing to monitor emissions from several sources. The standards are national emission standards for new and modified industrial facilities that contribute significantly to air pollution.

BP is also accused of failing to conduct timely performance tests of hydrogen chloride emissions from its catalytic reforming units.

The company has 10 days to request a conference to discuss the violations.

Repeated attempts to contact BP spokesmen for comment were unsuccessful early Friday morning.