It is a great need for approved disposal of alum shale – a rock that can sleep peacefully for several hundred million years, but it can be both acidic, toxic and cost-driving if its dug up or disturbed in other ways.
Alum Shale and the related black shales are generally naturally occurring rocks. Most of the rocks can be dug up and blown to pieces and pieces without changing the properties, but the alum shale can react in a way that makes the rock passive to an active source of pollution. Alum Shale also contains a variety of toxic heavy metals such as cadmium, copper, nickel and zinc, as well as arsenic, uranium and mercury. Sulfur acid causes the heavy metals in alum shale to be released and end up in runoff water, which can destroy local groundwater resources or kill fish, animals and plants if the water comes out of a river.
Today there is only one approved landfill for alum shale in Norway, namely the Langøya outside Holmestrand. The need for a new landfill is enhanced by the Norwegian Radiation Protection Authority and they have issued new regulations which means that the alum shale with a high level of radiation should be treated as hazardous waste.
Kim Rudolph-Lund from Norwegian Geotechnical Institute recommends that the County seeks a license as soon as possible to establish a new landfill, in cooperation with the affected municipalities.
Alum Shale is a rock with, to say the least, strange properties. When the seven-kilometer railway line from Jaren to Gjøvik was built in the laste 1800’s, it was used crushed alum shale as filler in parts of the trail. The result was that the stretch was snow-free in the winter in many years, because the fill mass developed so much heat that the snow melted.
After the millenium in 2000, the landowner had no problems, until a local environmental activist discovered that the stream from the landfill had become red and poisonous. The reason was that the deposited masses containing alum shale. Landfills with alum shale has also recently caused more pollution in other parts of Akershus and the southern coast.
The Norwegian Geotechnical Institute and a building company went together to start a project called “Black Shale” and their objective is, as quoted from their website;
“The objective of BLACK SHALE is to improve and further develop in a coordinated fashion sustainable geo-solutions for design in black shales, first for Norway and Sweden, and later for the international market. This ambitious objective requires multi-disciplinary research and development and new and improved approaches.”
So maybe this rock can be used to different purposes and help us to solve some of the problems that we face on this planet, it will be interesting to see.