Nearly all land near small runways and airports that fly planes using AvGas will have lead contamination. That’s because lead is still used in most aviation fuels a consumer plane would use. Runways are also required to have and use PFAS in firefighting foam for emergencies. Training and system tests will dump that stuff in the surrounding area.
Unless these fine folks have A380s they’re paying a hefty premium for lead exposure and PFAS in their water and soil.