We NEVER get rid of old/used candles, I then go to my woodshop cyclone trashcan and pack paper dixie cups with wood shavings. I then melt down the old candles on a hot plate and fill the cup with melted wax. Waterproof and pretty windproof too !
New Pig also carries containment pallets
https://www.newpig.com/pig-economy-2-drum-poly-spill-containment-pallet/p/PAK605
link is for a two drum unit for $226