EPDM is a tough material, similar to tire tube. I have used it for solar applications and walked on it on roofs. It is degraded by bitumen or oils, so it must be kept from oil-based materials. If the traffic is not frequent it should last. I have some tank bladder sheet material from 20 years ago as good as when purchased. Any piercings, such as nails or screws through the material should be done through a piece of patch with silicone caulking between to prevent leaks, then silicone drop over the fastener head.