(AP) - Delaware officials are reviewing their options after the Environmental Protection Agency said it won't act to force power plants in other states to reduce emissions blamed for Delaware air pollution.

The EPA late last week denied four petitions submitted by Delaware and one from Maryland. The petitions requested reductions in emissions of ozone-forming nitrogen dioxide from specific power plants in upwind states including Pennsylvania and West Virginia.

The EPA concluded that existing programs can address the concerns of Delaware and Maryland.

State officials say more than 90 percent of the ozone in Delaware originates from emissions in upwind states. They say the EPA may not be interpreting available data properly and is not implementing the Clean Air Act's Good Neighbor provisions as they were intended.