Digging deep to cleanse the soil

LEVERKUSEN, Germany — Much of the things we did in the past were done with little regard for their long-term effects on people and environment. It was not until the recent past that humanity finally realized the folly of its past actions and began to consider the environmental factor in most of its important decisions.

Indeed, we have today a voluminous set of laws defining what we should and should not do to make sure that the generations that will come after us will not inherit a benevolent environment, one that will not itself be a hazard but one that will be able to support itself and the people who live in it.

But things we did in the past have a way of catching up with us as they have done in many occasions. Wastes that have been dumped and almost forgotten have a rude way of reminding us about their existence.

This is exactly what happened to Bayer AG, a giant of a diversified international health care and chemicals group of companies. In fact, Bayer has gone through the experience of cleaning up two dumpsites — one in Japan and the other in Germany — to eliminate any danger to humans and the environment. And the exercise is costing Bayer a lot.

Of the two clean-up projects, the one in Tokyo is relatively more simple and straightforward. In fact it had been completed in early 2001 after 29 months of round-the-clock operations at a cost of 75 million euros.

The more complicated and the more expensive undertaking is the Dhuennaue Remediation Project which started in 1995 and which is scheduled for completion next year, after which the area will be transformed into a garden in time for an ambitious garden show coinciding with the 75th anniversary of the town of Leverkusen, the site of the project. Together, the remediation project and the garden show project will cost Bayer well over 100 million euros even with help from the municipal government of Leverkusen.

But cost is of little consequence to Bayer which, according to Dr. Udo Oels, member of the board of management of Bayer AG, has invested more than 12.5 billion euros in various places all over the world for the construction and operation of waste management facilities at the company’s production sites over the past 10 years.

Dr. Manfred Schneider, chairman of the board of management of Bayer AG, said: "Economic, ecological and social responsibility is a matter of course to us because we are aware that everything that we do as a company entails a responsibility to future generations."

In keeping with that responsibility, Bayer has spared no expense in extracting toxic wastes and cleaning up the soil in areas that had been used to dump and store waste spewed out by the group’s factories not only in Germany but in other parts of the world as well.

Two excellent examples of how seriously Bayer takes on such responsibility are the remediation projects in Japan and right next door to Bayer’s headquarters in Leverkusen, Germany.

The remediation project in Japan involves a former production site of Nihon Bayer Agrochem (NBA), a Bayer subsidiary. The site is located in Hachioji, a city of more than 500,000 inhabitants, which lies some 40 kilometers west of Tokyo.

The site was set up in 1942 in what was then a rural area. Today, only a single street separates people’s homes from the site where, until 1992, NBA manufactured crop protection agents.

The site was subsequently closed as the company moved all its production activities at another site. Bayer’s plan was to sell the property. But before going around to look for prospective buyers, Bayer conducted some tests and found out that part of the site was contaminated with inorganic mercury. Fortunately, extensive tests showed that no mercury had leached from the soil into the groundwater.

What Bayer did was to excavate the soil, extract the mercury from it and fill it back. A total of 66,000 cubic meters of soil was excavated and thermally treated on-site. The process was completed in early 2001 at a cost of 75 million euros.

The Leverkusen Dhuennaue rehabilitation project was a bit more complicated. Authorized by a contract with the City of Leverkusen, Bayer dumped some 6.5 million metric tons of waste on a former Rhine flood plain between 1923 and 1960 to protect the village of Wiesdor, now part of Leverkusen, from flooding. Ten percent of this waste consisted of production residues from Bayer’s nearby production site. Once the landfill site was complete, part of it was used for farming.

In the 1950s, the Leverkusen Council built 250 rental apartments and an old people’s home on another part of the site. Motorways were subsequently built over the area.

In the mid-1980s, however, Bayer began to receive complaints about certain gasses seeping out from cracks on the floors of houses built over the area. Investigations were made and once the potential for damage became known at the end of the 1980s, the municipal and state authorities joined forces with Bayer to devise a comprehensive rehabilitation plan.

According to Gunter Hesse, project manager of the remediation engineering division of Bayer, one thing was obvious: digging up the site as they did in Japan was not an option. Following consultations with experts, it was decided that a massive retaining wall about four kilometers long and up to 38 meters deep would have to be built to separate the entire contaminated site from its surroundings and to seal the surface effectively. Hesse said this was to prevent surface water from penetrating the site and stop contaminated groundwater already in the site from leaching out.

According to Hesse, all the homes in the contaminated zone were torn down and their inhabitants were given new homes elsewhere.

The remediation work started in 1995 and since then the ground water barrier which used a special material consisting of cement bentonite mixture of high concentration has been put up. Construction work is schedule to end in June next year after which a team of landscape artists will take over and transform a boomerang-shaped portion into a special park that will feature some of the rarest and most exotic ornamental plants in the world.

Stefan Kurl of the Coordination Office for State Garden Show, Leverkusen Municipality, said the project will cost an estimated 22 million euros and will be underwritten by the Municipality of Leverkusen, the Ministry of Traffic, Ministry of Town Planning and Ministry of Environment.

Kurl said they hope to complete the park — to be called Boomerang "Parc of movement" based on a winning design submitted by architect Brosk of Essen — in 2005 for a State Garden Show marking the 75th anniversary of the town.

By then, this former waste dump should have become the jewel in Leverkusen’s crown.