DON'T DUMP PROPANE TANKS

One of the biggest and most hazardous items that ends up in the waste stream at U.S. National Parks are the propane tanks used by campers and hikers for cooking and heating. Difficult to recycle, and often containing leftover flammable gas, these canisters are thrown in National Park Service landfills by the hundreds of thousands. To help reduce this bulky and dangerous source of solid waste in the parks, carry your large, 20- to 50-lb propane tanks out of the park and either refill them or swap them for new tanks at a retailer in your area. The smaller, more ubiquitous 1-lb (actually 16.4 ounce) propane bottles are a bigger problem: there's still no easy way to recycle these containers. However, users can still make them safer to dispose by ensuring that the gas is entirely burned off before discarding. Another option is to purchase refillable propane bottles, or a kit that allows you to refill 16.4-ounce propane bottles from a 20- to 50-lb propane canister. (However, be aware that federal law prohibits propane bottles refilled in this manner from being resold or transported across state lines.) The iso-butane fuel canisters commonly used by backpackers might be recyclable as "mixed metal" in your community if fully emptied of gas and punctured. All fuel should be fully burned off before puncturing the thin steel wall of the canister with a common "church key" style can opener. Note that these canisters cannot be safely refilled.