Last Updated: 29.03.2022

Used gasoline poses some environmental threats when not disposed of properly. Gas does go bad with time, and leaving some gasoline stored in the garage all winter long can result in it becoming contaminated or degraded.

Degraded old gasoline can damage some crucial internal engine components. In fact, it can form some gum that can end up causing blockages when used. If it has ethanol, it can draw water vapor into the vehicle’s fuel line resulting in internal corrosion. 

Simply pouring it into the storm drain or land can be detrimental to the ecosystem, and you could also incur fines. 

So, if you want to know how to dispose of old gas properly, please read on…

Discarding Old Gasoline

gasoline precautionary reminder

As mentioned earlier, gas poses a considerable threat if not disposed of properly. Pouring old gas in the toilet, storm drains, or on land can kill animals, damage the landscape or even contaminate water sources. Plus, it is illegal, so you need to learn how to handle old gas. 

Old gasoline poses a severe fire risk, so you should dispose of it properly.

Step 1: Inspect Whether the Gas Is Contaminated or Just Old

The first thing you should do is confirm the smell and appearance of the gas to determine if it is OK. Pour some fresh gasoline in a glass container and the old gas in another container for comparison. 

If the old gasoline smells sour or darker than the fresh one, it has lost its efficacy. Luckily, most gas suppliers add ethanol to their products to increase their shelf life. But after a while, it loses its effectiveness and degrades its combustibility. This will lower its ability to crank your engine.

So, instead of pouring it into your car’s gas tank, you can dispose of old gasoline. You can also reuse the old gas after diluting it with fresh gasoline. But if it has a few particles of discoloration, dirt, or rust, then it is contaminated.

old gasoline in a container

Contaminated gasoline can damage your engine, so you should never mix it with fresh gas and reuse it.

Step 2: Use the Old Gasoline

Generally, gasoline loses its potency and may not be able to start your car’s engine. But if it is not contaminated, then you can dilute it with fresh gasoline and use it to power your car or power tools. 

If you use the right proportion when diluting, then the old petrol will have a negligible effect on the gas in the tank. And it can still power the engine without damaging it.

If the lawn mower’s gas tank is half full, then filing it with fresh gas may get the engine firing in no time. Since you will burn it quickly while mowing the lawn, you can top it up midway and continue working.

If you have a large volume of gas, then you should dilute it in the car’s gas tank. So, the first thing you should do is find out your car’s tank capacity. 

For a 10 gallons tank that is 75% full, you can add half a gallon of gasoline. Measure half a gallon using a jerry can and then pour it into the gas tank. You can add a gallon of old gas to 16-gallon tanks or ¾ of a gallon to 12-gallon tanks.

When pouring it into the gas tank, you should ensure the gasoline doesn’t exceed the tank’s safety flap. The metal flap is normally pushed into the gas tank’s mouth when closed. This prevents the gasoline from spilling into the region between the gas cap and the tank’s mouth.

pouring fuel additive to old gasoline

Make sure you find out which fuel additive can help increase the fresh to old gasoline ratio that can be added to the fuel tank. A fuel injector cleaner can also help you reuse the old engine, but this will depend on fuel and engine type. So you can talk to the employees at the local automotive shop for advice.

But if the fuel has a dark coloration like milk chocolate or rust-brown, you shouldn’t reuse it because will leave some impurities and deposits in the engine.

Step 3: Look for the Nearest Old or Contaminated Disposal Centers in Your Area

Since you can’t pour the old gasoline just anywhere, you’ll need to find the designated place where you can dispose of it. The first thing you should do is search for hazardous waste sites in your home state or city. 

If you don’t find a place for disposing of old gas online, you can call the city or county waste management agency. Ask the waste management agency where old gas goes.

Given that gasoline is flammable, you should contact the local fire department and ask them how old gas should be discarded. The fire department is also known for frequently giving lots of methods for disposing of gasoline. 

The fire department can also help dispose of the gas or suggest how to transport and safely store the gas.

containers with old gasoline

If you don’t have any other options, you can ask the local auto repair shops for assistance. Unfortunately, most shops won’t accept it, but a few auto shops can accept the old gasoline. So, if you have an exceptional relationship with any auto repair shop, you can talk to them.

Step 4: Transfer the Old Gasoline to Government-Certified Containers

After finding out where you can take the old gasoline, you should find out how to transport it. The best solution for transporting old gasoline is by using a government-certified container. Most government fire codes require the container to store below 5 gallons. So, you can get the government-certified containers from the gas station or the automotive centers.

Pour the gasoline slowly to avoid spillage, static, or splashing and fill it up to 95%, leaving enough space for the fumes. Keep your face away from the container’s spout while pouring the gasoline to minimize the quantity of gas you inhale. After pouring the gas, seal the container to prevent spillage.

Place the gasoline container in another receptacle like a bin or rubber cooler. Make sure it’s upright to prevent it from toppling over and leaking when driving. In case of spillage, you should wash your hands thoroughly.

Step 5: Get Rid of the Gasoline Spills

If the gasoline left any stain on your clothing, you should address it immediately. Start by blotting the excess gasoline off using a white piece of cloth. Apply some baking soda on the affected region to help absorb whatever is left by the white piece of cloth. Let the baking soda sit for a few minutes before brushing it clean.

You can treat the stain for five minutes using liquid dish soap before laundering your clothes using hot water. Line dry the cloth after removing all the gasoline stains; otherwise, it can become combustible.

If the old gasoline spilled on your driveway, you can soak up most of the fuel using an absorbent product. An absorbent product like the kitty litter can take a few hours to absorb the fuel. Finally, you can sweep the kitty litter and dispose of the gasoline from the driveway.

Step 6: Transport the Old Gas to the Disposal Center

Drive the truck while transporting the old gasoline, and don’t smoke while driving. After all, some gasoline may have spilled on your truck or clothes. Remember, it takes a small amount of gas to be combustible when exposed to open flames.

When you arrive at the disposal center, make sure you empty the old gasoline in the storage vessels. Then, take some empty 5-gallon containers home for the next time you will be disposing of some old gasoline.

Safety Tips When Disposing of Old Gasoline

Gasoline is a flammable and highly toxic liquid that should be handled carefully. Thus, it is important to follow these unique requirements when disposing of gasoline. 

  • It’s dangerous to inhale a huge amount of gasoline; therefore, you should work outside. If you feel a burning sensation in your lungs, you should go outside and breathe in some fresh air.
  • If you get some gas in your eyes or skin, you should flush the gasoline out using a lot of water for 15 minutes. If the burning sensation continues after washing it off using cool water, you should contact a medical professional.

Also find out: What does sugar in a gas tank do?


Gasoline tends to degrade with time and lose its ability to start the engine. But if it is not contaminated, you can mix it with some fresh gas and reuse it. If it has dark coloration or smells, it is contaminated and can damage your car’s engine. So make sure you dispose of the contaminated gasoline properly; after all, it is hazardous and can affect the environment.