PERU, Ind. (AP)  A new study found that noise pollution near Grissom Air Reserve Base in northern Indiana has fallen over the past two decades and suggests that more residential development could be allowed nearby.

The study by military officials found Grissom's overall noise impact has dropped by 20 percent since 1994, when it was downgraded from full Air Force base status to a reserve base, the Kokomo Tribune reported.

Grissom commander Col. Doug Schwartz said the number of military flights decreased during that time and the KC-135R Stratotanker refueling planes stationed at the base between South Bend and Indianapolis have quieter engines than they once did.

The noise pollution drop has occurred even though civilian air traffic has increased with a jet-painting company and other businesses using the Grissom runway, which is more than 2 miles long.

The report recommends new planning and zoning guidelines for nearby communities to ensure future compatibility with the base's operations.

Schwartz said he hopes local officials will use the study as a tool to determine what type of development is appropriate around Grissom.

“We all know this area will be developed,” he said. “What will it look like in 15 or 20 years? There's a lot of exciting things happening, but without these kinds of studies to do proper development, we could get in each others way.”

Jim Tidd, executive director of the Miami County Economic Development Authority, said county officials will incorporate the study's findings into a new comprehensive plan being developed this year, but must remain cautious about allowing construction too close to Grissom.

“Even though there's been a reduction, we continually need to coordinate with the base and people looking to develop around it to make sure we don't do anything to jeopardize our aviation potential,” he said.