Used Tire Retaining Wall Safety and Toxicity Concerns

Stacking tires for slope leveling: tires shift without reinforcement. Steel belts degrade, leaching zinc, PAHs, and heavy metals into soil—questionable for planting areas.

Better: timber, block, or stone walls. If using tires: pin with rebar, fill with gravel, cap with soil. But toxicity remains concern for edibles.

Need: wall location (above/below plants), stack height, drainage plan. Tires not recommended for structural walls near living spaces.