Hazardous waste like gasoline needs special handling for disposal
If you store your gas-powered mower or other lawn equipment for the winter, any gas still left in it will be too old to use when it comes time for the first mow of spring. Old gas must be carefully disposed of since it’s considered hazardous waste. Improper disposal can cause fires, serious environmental consequences, and fines or citations.
Learn how to dispose of old gas safely and responsibly.
Safety note: Because old gasoline is considered hazardous waste, it’s important to be careful when handling it and that you dispose of it properly. We’ve included safety precautions throughout, but generally, you should always take your time when working with gasoline, keep it away from any heat source, and wear protective equipment like safety glasses and gloves. If you’re not confident you can safely dispose of old gasoline yourself, it’s best to call in a pro.
Wondering whether the gasoline you have is considered “old”? Old gas is typically gas that is two months or older. Depending on the situation, it may be possible to recondition it and reuse it. If not, you need to dispose of it. Old gas smells a little stale or spoiled, so if you’re getting a weird odor, there's a good chance it's old. Another way to test it is to pour a small amount into a clear container and compare it to new gas. If the old gas looks darker than the new gas, you’ll know that it’s not usable as-is.
Many local hazardous waste disposal programs are free for households. In some areas, there are limits to the amount of hazardous waste you can dispose of for free, ranging from around 15 to 35 gallons. If you're disposing of old gasoline for a business-related reason, you may incur a cost for hazardous waste disposal.
Although the disposal programs are free, you may have to buy a government-certified container to transport the old gas if you don’t already have one. These cost around $20 to $40.
On the other hand, you may opt to hire a local hazardous waste disposal company to do the work for you, especially if you’re nervous about safety or have a lot of old gas. Hazardous waste disposal services start at $50.
Refer to this table when disposing of old gas, making sure not to take any unnecessary risks.
| Do | Don't |
|---|---|
| Wear gloves and safety glasses | Pour gas down storm drains or septic systems |
| Clean up spills with cat litter | Pour gas on the ground |
| Keep gas in an approved container | Throw gas in with trash or recycling |
| Keep gas away from sparks and flames | Mix gas with other liquids |
Before working with gasoline, it’s important to remember that it is highly flammable and toxic. When handling it, it's a good idea to wear disposable gloves and safety glasses to avoid any gas splashing into your eyes or onto your skin. And to be extra safe, have some cat litter on hand to sop up any spills.
Make sure you keep the old gas in the right container until you're ready to throw it away: This can be a UL-approved metal safety can that meets OSHA standards or a plastic gas container.
Additionally, store the old gas away from kids, pets, heat sources, and ideally, away from the house. Heat sources include the sun, water heaters in the garage, furnaces, and space heaters. Keep any gas at least 50 feet away from anything that could cause a spark, like pilot lights on propane appliances.
If you've accidentally spilled gas onto your clothes, you should change as soon as possible. Blot the spill with a rag, and then put baking soda on it. Use a liberal amount and make sure that the stain is completely covered. Soak the clothing in a tub with a 1:1 mixture of vinegar and water, and finally, wash it in your washer and let it air dry.
If you accidentally get gas onto your skin or into your eyes, take quick action. Rinse your eyes with lukewarm, gentle water for five minutes with your eyes open. If gas gets onto your skin, wash it off thoroughly. If irritation persists or gets worse, seek medical attention.
Since old gas is hazardous waste, you need to dispose of it through a local hazardous waste program. Doing so properly is important: According to the Utah Farmstead Assessment for Groundwater and Surface Water Protection, one gallon of gasoline can contaminate up to a million gallons of water.
In addition to contaminating the groundwater, spilled gasoline can damage the landscape, kill animals, and increase the risk of fires. In many places, it’s illegal to throw away gasoline anywhere except for hazardous waste facilities.
"Illegal dumping poses significant environmental hazards. Hazardous materials can contaminate soil, waterways, and ecosystems, leading to pollution, habitat destruction, and harm to wildlife. Additionally, improperly disposed of waste can contribute to air and water pollution, posing health risks to humans and animals. "
— Sean Foley, President of redbox+ Dumpsters
Below are some steps you can take to dispose of gasoline safely.
Find your local hazardous waste disposal program by searching the internet or by calling 1-800-RECYCLE (1-800-732-9253). Your local program can inform you of specific guidelines they have for gasoline disposal.
Follow these steps to safely dispose of your gas at a hazardous waste facility:
Pour or siphon the gas into an approved container if it isn’t already in one.
Place the container in a sturdy box in the trunk of your vehicle to keep it stable.
Drive to the facility and follow instructions for disposing of the gas.
Reconditioning gas is only possible if it’s uncontaminated. It’s a great way to recycle and reduce your environmental impact. But before using reconditioned gas, consult your owner’s manual for the item you’ll power with the reconditioned gas. Be aware that there’s no guarantee that reconditioned gas will work effectively, and it may damage engines when used.
You’ll also want to practice extreme caution here, take your time, and only recondition gas if you’re confident you can do so safely. If in doubt, it’s best to dispose of the old gas and get fresh gas.
If your gas is uncontaminated, remove any particles that have settled in the gas. First, find a suitable container to pour the gas into, and place a coffee filter in it. You can secure the filter onto the container with an extra-large rubber band. Next, use a funnel to siphon the old gas through the filter. You should do this outdoors on top of a tarp for easy clean-up in case you accidentally spill any gas. Take your time and wear gloves and eye goggles as a safety precaution.
Be careful with the coffee filter after using it because it will be highly flammable. After you’re done, place the filter into a metal container with a lid, and then fill the container with water. You’ll then need to call your trash service and see if they can do a special pickup for the container, take it to your local hazardous waste facility, or call a hazardous waste pickup service.
Once you have filtered your old gas, add five parts of the new gas for one part of the old gas to the container.
Fire departments may offer drop-off service for old gas. The gas is collected at the station and brought to the appropriate disposal facility. Not all fire departments offer this service, so contact your local station first to find out if they participate and what steps you need to take.
Some municipalities sponsor community hazardous waste removal events to make disposal easy and encourage community members to dispose of these materials responsibly. Check your local government or sanitation department’s events calendar to see if they offer these events and learn any applicable guidelines.
Local auto repair shops and garages may accept old gas for free or a small fee. Because these businesses regularly work with hazardous materials, they can sometimes take your old gas and dispose of it along with waste from the shop. Call around to inquire if any local shops offer this service.
Because disposing of old gas can be an involved process, it’s better to try to use up any gas you have on hand before it goes bad rather than having to dispose of it later on. Don’t keep more gas on hand than you’ll need in a season—it’s less complicated to fill up a gas can if you run out than it is to dispose of anything left over.
If you’re approaching the end of the mowing season and you still have gas to use, consider using your mower to mulch leaves. If the gas is fresh, stored in an approved container, and the same octane you use in your car, you can also add it to your vehicle’s gas tank to use it up.
If handling gasoline seems like a task that you don’t want to deal with, hire a waste removal company in your area. Just be sure to tell them that you have hazardous waste, not regular residential waste.
When you hire a pro, you can be sure they’ll dispose of the old gas safely, and you won’t have to give it another thought.
Mizuki Hisaka contributed to this article.
Most likely, if your gas is two years old, you’ll need to either recondition it for reuse or simply dispose of it. Over time, the gas degrades and becomes less volatile. There could be contaminants in the old gas that can enter your lawn mower or car engine, which can cause damage. If you use gas that’s older than a year, you might notice engine knocking or clogged injectors.
Although gas will technically evaporate over time, it can be dangerous to leave gas out in the open for an extended period. So, no, it’s not recommended that you allow gas to evaporate. The gas is highly flammable, so you could accidentally start a fire, and it’s also dangerous because it emits toxic fumes.
It depends on how you store the gas. If it was sitting in a machine like a lawn mower, and if it’s been longer than a couple of months, it’s best to recondition the gas for reuse or dispose of it. On the other hand, if the gas is in an approved gas container, it can stay fresh for up to six months.
Oxidation, evaporation, and contaminants can all cause gasoline to degrade. Over time, exposure to the air will cause the chemical components in gas to evaporate at different rates and degrade the remaining components. Old gas becomes less combustible and can damage engines or make them work less effectively.
Storing gas properly in an airtight container in a cool, dark place and adding fuel stabilizer may extend its life. Fuel stabilizers are sold commercially and may keep your gas usable for longer. Gas that’s left in a mower or other equipment will begin to degrade quickly, so try to use up gas by the end of the season.
