How long does gasoline stay in soil?

If you’re wondering how long does gasoline stay in the soil, know that you’re not alone. It is one of the most frequently asked questions concerning gasoline. However, there seems to be little to zero answers on the topic out there. Needless to say, it’s time for a change.

Look at us, being all mighty with emotionally-charged sentences. Know that you’re not alone. It’s time for a change. It’s as if we’re writing a protest hymn or something. Anyway, let’s roll back towards today’s main subject. In the article below, you’ll find out how long does gasoline stay in the soil.

If it’s a minor spill we’re talking about, gasoline will go away quickly. Forget about planting anything (especially edibles) on the spot where the spill was. If it’s a bigger spill (5 gallons or more), there’s a chance it’ll take years for gasoline to dissipate. 

Wondering if there’s more to the subject? If that’s so, feel free to keep on scrollin’!

Table of Contents

Gasoline spills 101

Let’s talk about gasoline spills first. There’s a good chance you’re reading this text because of one. Anyway, you’ll want to know that gasoline spills aren’t to be taken lightly. In other words: one must tackle the issue immediately. Why’s there such a hurry, you might ask?

Is gasoline toxic?

As you may have heard, gasoline releases toxic fumes when exposed to air. Gasoline evaporates at temperatures above -40°F (-40°C). A quick note: that wasn’t a mistake, -40°F is -40°C, there’s no difference. Great, now you’re equipped with some unusable-unless-you’re-in-a-quiz knowledge. Anyway, gasoline fumes are a serious safety risk!

Do you ever see anyone smoking at a petrol station? We reckon your answer’s: nope, never. That’s because even a spark from a cigarette can cause mayhem. Gasoline is pretty darn flammable, accidental fires caused by it aren’t so rare.

Do gasoline spills float on water?

In simplest words: yes, it does. Gasoline naturally tends to float on top of the water surface. Also, it’s quite harmful to the animals inhabiting the water it contaminated. That one goes without saying. It’s damaging enough to destroy sensitive ecosystems.

Does spilled gasoline evaporate?

Well, this ain’t a yes or no type of answer. The thing is: spilled gasoline will eventually evaporate, of course. Still, how fast it’ll happen depends on the surface it’s spilled onto. In other words: whether we’re talking about pervious or impervious surfaces:

  • Case #1: You’ve spilled some gasoline onto asphalt or concrete. Result: it will probably evaporate quickly and go away, in a sense. After being cleansed first, of course.
  • Case #2: You’ve spilled some gasoline onto bare ground. Result: It depends on a few factors. We’d have to consider the nature of the surface (sand, clay, etc.) and the amount spilled. Additionally, it depends on the level of the underlying water.

Keep in mind we’re talking about smaller spills (5 of fewer gallons) in Case #2. Minor spills will evaporate pretty quickly and go away. This happens due to the processes such as:

  • evaporation.
  • dispersion in the soil matrix. 
  • dilution by soil water (rhizic water).
  • degradation by soil microbes (bacteria and fungi). 

However, larger spills are a big issue since the mentioned processes can take forever. For instance, imagine a spill worth a couple of hundred gallons. It would take decades before it goes below undetectable levels.

All in all: we’ll talk a bit more about this in the main section of this article. Check what’s under the photo!

A gasoline spill on the concrete ground.

How long does gasoline stay in soil?

Imagine you’ve tried to kill some weeds using gasoline. That’s a common mistake that should be avoided by all means. Yes, it will remove the weeds. However, it will leave behind poisonous soil.

There are more eco-friendly weed-killing options you’ve got. For instance, you can make a homemade vinegar solution. You’ll find it in the article we’ve linked on the top. Anyway, let’s dig deeper into the gasoline-stained soil.

The factors

Previously in the text, we’ve mentioned that how much will gasoline stay in the soil depends on a few factors:

  • the type of the surface (pervious or impervious).
  • the amount of gasoline that’s spilled. 
  • the level of the underlying water. 

That being said, we can note that soil is definitely a pervious surface. That means that it will soak in the spilled gasoline. Okay, so we’re left with the question: how much did you spill?

First things first, regardless of the size of the spill – don’t grow any edibles on the spoilt soil. You might want to dig out the spot where the spill “happened”. Dig until you notice the specific odor’s gone and replace old soil with fresh soil. Dispose of the poisoned ground you’ve dug up in the correct manner. That means you should probably consult your local laws on hazardous waste disposal.

Also, we’ve got your back on the last one. If you’re wondering how to dispose of gasoline safely, follow this link.

So, how much did you spill?

If you’ve spilled a lot (more than 5 gallons) – it’s gonna be tough. We’re talking months or even years before the gasoline goes under undetectable levels. Minor spills will, of course, evaporate quicker. Although you should still avoid planting anything in that soil.

Now, here’s a catastrophic scenario. Imagine your spilled gasoline reached groundwater. That’s something you don’t want to happen. Of course, there are a lot of factors to consider to calculate when exactly will it go away. For instance, geological composition and/or hydrological conditions. Anyway, the process can last hundreds, quite possibly even thousands of years. 

How to prevent these accidental and sometimes intentional spills?

First, let’s see how you’ll prevent some intentional spills. In other words: what should you avoid doing.

Avoid using gasoline as weed-killer

We know, we know… Weeds are nothing but a pain to deal with. Once you think you’re done with ’em, here they are again. Unfortunately, some irritated gardeners turn to gasoline when dealing with this issue. Needless to say, it will ruin the soil you’re working on. Also, many folks succeeded in polluting their own drinking water by using this “method”. 

As we’ve said a hundred times, gasoline is highly flammable. You really don’t want your lawn to go up in flames. Luckily, there’s an alternative weed-killing method. It’s very simple: just make the vinegar solution we’ve talked about upstairs.

Avoid using gasoline as ant-killer

If you’re irritated by ants in your backyard – that’s one thing. If you’re planning to kill ’em all (as Metallica once said) using gasoline – that’s another thing. You’ll put your family at a serious health risk. There are much better ways to get rid of ants:

  • hire an exterminator. 
  • keep a tidier kitchen. 

Both options are more obvious than using gasoline. You won’t have to worry about whether you’ll blow your yard into nothingness.

Okay, now let’s talk about the so-called unintentional spills.

Avoid using gasoline as a fire-starter

Of course, it might seem like a good idea, but only at first sight. You might want to use a bit of gas to “improve” your bonfire. Not only can you spill some but your action might cause an explosion. It’s not the liquid that burns, it’s the vapors. Did you know that one gallon of gasoline can cause a 14-dynamite-sticks kind of explosion?

All of the things above are reasons why you shouldn’t use gasoline near an open flame. What’s wrong make a fire in the traditional manner?

Avoid storing your gasoline in unapproved containers

Did you know that gasoline can easily dissolve most kinds of plastic? Forget about storing your petrol inside milk jugs or somethin’. It’s like you’re buying a ticket for disaster. There’s a reason why EPA-approved containers are made from HDPE.

If you’ve read at least one or two articles on this blog, you’ve seen the acronym HDPE appearing a lot. It stands for a high-quality form of plastic called high-density polyethylene. The components of this type of plastic make it strong enough to withstand gasoline.

If this topic interests you more, we recommend you pay a visit to this page. Now we’ll show you how to store gasoline safely (besides using HDPE containers):

  • keep it stored out of children’s reach. Playing with gasoline is a no-no.
  • keep in a room that has no heating sources. Also, store it away from the path of direct sunlight.
  • don’t keep it in this same house you sleep in. An outdoor shed/garage will do just fine.
  • check your local/state regulations on gasoline storage. Also, don’t forget to check your homeowner’s insurance policy.

As you might already know, proper storage of gasoline is basically a must. Keep that in mind just so you avoid provoking unnecessary mishaps. For more tips on safe gasoline storage, read this text.

Parting thoughts

That’s about it on the whole how-long-does-gasoline-stay-in-soil thing! We hope you’ve had fun reading our take on the subject! Until next time, make sure you keep your gasoline safely stored! Lastly, avoid spilling it onto the soil, or any other permeable surface!