In 1958, a large Swedish army depot exploded, with 14 million litres of fuel leaking into the surrounding environment. Since 2011, RGS Nordic has been working to clean up a 25,000 m2 area of inaccessible forest and fields heavily polluted by the spill.

The massive spill had spread from the military bunker across fields, through woodland and into a nearby lake through the area's sewage system. After the accident, the clean-up involved burning the fuel floating on the lake or gathered in pools in nature.

The large amount of fuel that had soaked into the ground was allowed to remain for decades. In 2011, a thorough remediation of the area was planned, and RGS Nordic was chosen to perform this demanding task.

A solution tailored to the location 

The first step was to remove approx. 5,000 tonnes of contaminated soil, which was easily accessible. Then we started a series of pilot studies to investigate how we could best clean up the large forest and field area that had to be cleaned in situ.

Working in the hilly moraine landscape with dense vegetation and great variation in depth on the rocky ground was a challenge. But by combining various methods, we developed an integrated solution that gave very satisfactory results in pilot tests.

The first step was to remove about

5,000 tonnes of

contaminated soil,

which was easily accessible.

From pilot to full-scale clean-up

The experiments included the direct injection of a bio-stimulating agent (ORC Advanced), and a chemical oxidising agent (REGENOX). After the trials, measurements showed a reduction in contaminants of 50-99% in the test area, and based on the good results, we decided to go ahead and clean up the whole area.

Part of the area also underwent treatment with multi-phase extraction and in situ soil remediation in places where the contamination was particularly intense.

When the clean-up was complete, control measurements showed that 85% of the area now complied with the defined target values. A second injection of REGENOX and possibly ORC has been planned for the remainder. Then the whole area is expected to be clean.

The finance made sense too 

This case shows that the in-situ treatment of contaminated areas can be executed cost-effectively and with great results when the solution is developed on site and local conditions are taken into account.

Combining different techniques meant that the cost of the project was significantly lower than if we had chosen to use a single method to complete the whole task. Calculations showed that the integrated solution cost between 25% and 55% of a conventional solution.

What can we help you with?

At RGS Nordic, we specialise in complex pollution tasks. Contact us for an informal chat about your challenge.