Councillor Brenda Johnson is repeating calls for a “paper trail” about farming in contaminated lands around the airport.

The Binbrook councillor reiterated her request at Wednesday night’s council meeting for documentation that proves the farmer who leases the airport farmland knew the risks relating to the perfluorooctane sulfonate (PFOS) pollution. She also asked city staff to look into where the soybeans grown in the area ended up.

The province’s environment ministry has asked airport manager Tradeport to create a no-farming “buffer zone” around ditches leading away from the contaminated site after local biologist Joe Minor raised concerns about crops grown on the property. Airport officials have said soybeans and winter wheat grown on its property are sold to commodity purchasers.

Firefighting foam laced with the chemical was used in training at the airport 30 years ago.

City council and the federal government, which owned the airport until 1996, are wrangling over responsibility for the cleanup, which could cost up to $4 million. The federal government has denied responsibility, pointing to a 1996 land transfer agreement.