June 2018, Vol. 245, No. 6

Features

Detecting Vandalism, Theft During Normal Operations

By Rene Landstorfer, Operations Manager, Gottsberg Leak Detection GmbH & Co. KG, Oststeinbek, Germany

Pipelines have always been subject to vandalism and theft. In recent decades, political conflicts have sometimes led to acts of sabotage and terrorism in which pipelines were damaged and catastrophic consequences occurred.

Currently, though, pipeline theft has become a greater issue. Fuel theft in Mexico, for example, has evolved from a small-time criminal activity carried out by robbery rings and corrupt distributors to a sophisticated operation linked to Mexico’s main criminal groups: the drug cartels.

Thieves drilled about 2,500 illegal taps in the first nine months of 2014 and stole more than $1 billion in fuel. In an interview, one gang member said he chose oil theft as a safer alternative to armed criminal activity, adding that stealing 10,000 liters of crude from one pipe represented a profit of about $4,600, and that tapping the pipeline took about half an hour.

Additionally, such an endeavor is seen as safer from a prosecution standpoint than smuggling drugs. A Mexican law enforcement official said if you manage to hold a suspect, it is still complicated because it is almost impossible to determine the owner of stolen oil.  “Who does it belong to?” he asked.

This is not just a problem unique to Mexico. Hot tapping and thievery at pipelines is a growing concern worldwide. In China, it is estimated to be the cause for 40% of all pipeline leaks.

In England thieves stole 1.4 million gallons of fuel from a pipeline that crosses the Liberal Democrat Deputy Prime Minister’s land. This was an $11.27 million (£8 million) oil heist; almost 300,000 liters a day of oil was stolen from the pipe, which runs under Clegg’s Chevening House estate, in Sevenoaks, Kent.

Similar crimes have become more common in Germany, as well. The first major incident there occurred in 2013, when a 12-inch product line was tapped, resulting not only in the theft of product, but also the pollution of 5,000 square meters of land.

The thieves in these cases are often well-equipped and adept at evading detection. They may, for example, vary their methods by implementing intermittent taps, graduated taps or smaller-volume taps. In many cases the thieves gain information on product shipments through their contacts within operator organizations, enabling them to pinpoint when and where to begin siphoning.

The thieves drill such small holes that many online leak detection systems cannot expose them. Even the amount of product removed is often not large enough to be detected by flow measurement from the input to the output of the pipeline.

Defects from hot-tap drilling along the pipeline that aren’t detected with metal loss or crack detection pigs can lead to leaks that may not be recognized through permanent monitoring technologies. This is because they account for a leak rate of only a few hundred liters per hour during the operation.

In most cases, thieves simply attach a valve and a hose – sometimes kilometers in length – to transport the product from a hot-tapping location.  The product may be loaded into vans equipped with tanks. Sometimes, underground storage facilities have even been used.

Solutions for Detection

In worst cases, the criminals leave without shutting off the generated leak, resulting in environmental damage, product loss and injury to the operator’s reputation, even though the operator was not at fault. 

Technology is available to find hot-tapping spots when they are created. Optical fibers, for example, can be installed along a pipeline to detect the vibrations that occur when thieves drill into the pipe wall.  This solution is limited to new pipelines, however, due to the prohibitive cost of adding optical fibers to existing underground lines. An additional drawback is it is relatively easy to disable such systems by cutting the fiber.

Gottsberg Leak Detection (GLD) is developing sophisticated leak detection pigs capable of detecting smallest leaks or siphons down to a leak rate of less than 10 liters per hour. This is well below the amount that would be lucrative for oil theft. The tool is only effective when the leak is open, however, because it is designed to recognize the noise that arises from cavitation, which occurs when a pressurized liquid expands to a vicinity with lower pressure.

GLD has done testing to evaluate the potential for detecting hot-tapping into a long hose attached to the actual leak. As sound travels well in liquids, the pressure difference producing the cavitation can also be far away from the actual hole in the pipe wall and therefore be detected reliably with the GLD tool.

There are other ways to solve this problem. One option is to is to do runs frequently, particularly when the thefts are anticipated to be most likely. Another approach is to place the tool on standby into the launching trap, then start the run when a theft is taking place. This can be done when the operator knows tapping occurs at a certain time of the day, and when the SCADA system recognizes discrepancies in flow or pressure. P&GJ

Editor’s note: The original version of this paper was presented to at the Pipeline Technology Conference 2016, in Berlin.

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