By VICKI URBANIK

The hot, muggy conditions in the past week in Northwest Indiana resulted in exceedances of the federal ozone standard, but it remains to be seen how the readings might affect Indiana’s current petition to redesignate this area as an “attainment” region.

On Friday, three monitors exceeded the ozone standard of 85 parts per million over an eight-hour period: The Whiting monitor showed a reading of 95 ppb, and Ogden Dunes and Gary both had readings of 89 ppb.

On Sunday, Whiting, Ogden Dunes, Gary and LaPorte all showed eight-hour exceedances, with the highest readings that day in Whiting at 91 and Ogden Dunes at 90.

Scott Deloney of the Plan and Policy Section of the Indiana Department of Environmental Management’s Air Quality division said IDEM will re-validate the readings.

Until IDEM conducts that quality assurance, it can’t say how, or if, the exceedances might jeopardize the state’s current petition to redesignate this region.

Lake and Porter counties have long been designated a non-attainment region for ozone, which has led to certain industry restrictions and the requirement that motorists get their vehicles emission tested.

Last year, after three consecutive years in which the monitors showed no ozone exceedances, Indiana formally petitioned the U.S. Environmental Protection Agency to reclassify this area as “attainment.”

And last month, the EPA announced that it has proposed approving that redesignation.

Deloney said IDEM has already been in discussions with the EPA about the exceedances and what impact they might have on the current petition.

He also said the EPA likely won’t make its final determination for redesignation for at least several months, and so it will have time to study the air quality, and any other exceedances that might occur, during the rest of this summer.

If the area is redesignated attainment, industries would no longer have to offset their ozone-forming emissions as they currently do. Motorists, however, would still have to get their vehicles emission tested.

The state had previously planned to seek a redesignation in 2002, but those plans came to a sudden halt after monitors in Michigan City showed violations after a bout of hot, muggy summer weather.

Ozone, commonly called smog, is formed when a mixture of pollutants react on warm, sunny days. The pollution comes from vehicle emissions, factories and other sources.

IDEM has so far issued about five ozone “Action Days” for Northwest Indiana, which alert the public for the potential for poor air quality.

On those days, residents are urged to carpool or take mass transportation and not to refuel their vehicles or mow their lawns except in the early morning hours and evenings.

People with respiratory problems, the young and the elderly are also urged to limit their physical activity when the air quality is expected to be dangerous.

Posted 6/20/2007