The EPA will be flying a plane on Tuesday to collect background levels of various airborne chemicals - and possibly radiation - as federal, state and city emergency departments get ready for this summer's World Cup, 250th-anniversary and Tall Ships events.

The city says the EPA is working with it and State Police on collecting the data as part of the EPA's Airborne Spectral Photometric Environmental Collection Technology program, which can create a series of "baseline" reports that could be used to determine if anything out of the ordinary happens during those events.  The Energy Department does a similar annual background-radiation survey along the Marathon route, only with a helicopter.

The EPA plane will fly in a grid pattern over the Harbor, Charlestown, Beacon Hill, Downtown, the Seaport, South Boston and Dorchester. It's a white single-engine plane with large blue stripes and says ASPECT on the side.