Best Tank Sweep
We get asked all the time what is the best tank sweep?
The answer is always the same, you get what you pay for. Metal detectors cost between $700 and $1,200 to purchase so that $200 metal detector inspection is not replying on expensive equipment to find a tank. In fact if you rely on a metal detector you are also hoping that a tank is the only metal on the property. You are hoping that concrete doesn't have any wire mesh, that no metal fences exist. The soils won't have any naturally occurring metal and that all buried metal utilities (sewer, water, gas) are not made of metal.
Metal detectors are non discriminatory so any metal found gives a signal and can fool the user. We have dug up numerous supposed tanks that a metal detector found which were in fact not tanks.
Commercial sites have used geophysical equipment to scan for buried anomalies, the most versatile is Ground Penetrating Radar (GPR). GPR units cost tens of thousands of dollars and have different antennas with different frequencies depending on what you are scanning. The advantage of GPR is you get an image on the unit screen so you can see what is below ground. You see the radar will reflect off a tank and bounce back to the cart. Don't get me wrong the image is not something you will see on a TV crime show, but to the trained user. That mountain image below, well that is a tank, the image is distinct. We can also verify with a metal detector, but would not use a metal detector as the sole technology, just too unreliable.
This rather long tank was not found by a metal detector, because of the depth of the tank and because pavers were on top of the ground which diminished the signal.
The best tank sweep, uses the best technology, which includes multiple technologies, hence why a GPR located image can be verified that its metal with a magnetometer. The photo below, well we were told it was a tank found by a metal detector, we were hired to remove it, got a permit and when the inspector came out he said with a straight face "you don't need a permit to remove a rock".
Here is a photo series of a tank sweep, Curren located a tank in the front yard for a buyer. The property owner was there and was surprised a tank was found in the front yard. We asked him how many tanks he has removed, "not many" was the response. We explained that there was no standard for where tanks were buried, could be on any side of the house (front, backyard, side yard). In this case tank was between the driveway and front yard. Since we were working for the buyer we couldn't paint the location of the tank so we marked it out with orange cones. Note the tank is under the sidewalk.
The next photo shows the tank being excavated and no it is not buried that shallow.
You see in this photo that the top of the tank is several feet deep.
Aside from using a multitude of technology to perform a tank sweep, you want the technician to have experience with removing tanks, so the company doing the sweep should also remove tanks. Why?
How can you be good at finding tanks if you haven't removed tanks? There really is no rhyme or reason as to tank placement, so working with a company that does tanks tweeps and removes tanks lends the experience you need.
Case in point, the other photo series shows you a tank next to a house. Well you can't even see the house in this photo!
What happens if you find a tank? I know everyone doesn't was us to find a tank, but we get hired to look for them. So when we find a tank, we provide costs to remove the tank with the report. We are licensed for tank work in NJ, PA & DE, so we can provide costs for the work. 60% of the time the owner hires us, the other 40%, well the owner is upset that we found a tank.
In realty, it does not matter if Curren gets hired to remove the tank or not. The important thing is a tank was found, the property owner is aware and has costs to address the tank. You just want the tank removed and tested, don't walk away from the property after we find a tank, because the next property could have a tank. Unless of course the owner refuses to remove the tank, then consider ending the contract, nobody needs a $100,000 cleanup.
We locate tanks, remove tanks, test tanks and remediate and have been doing it for over 20 years. Call the experts.