Presentation on theme: "GRUINARD ISLAND CEM AKER – ALI OZGOREN. The Location and Geographic Features Located on the northwest coast of Scotland, in Gruinard Bay. Total area of."— Presentation transcript:
The Location and Geographic Features Located on the northwest coast of Scotland, in Gruinard Bay. Total area of 1.5 square miles and two miles from the main land. Vegetation on the island consisting of moss, heather and some braken. Soil Properties: Torridonian sandstone overlaid by 0.3 to 0.5 meters of blanket peat bog.
The History The situation of the 2nd World War led the British Military to test biological weapons to use against the Germans. At the end of 1941, British Ministry of Defence declared the island a prohibited area, to test the chemical Anthrax.
The Test On July 5th, 1942, eight sheep were transported to the island. A bomb containing Anthrax was dropped on the island and exploded 4 feet above ground. The sheep were dying by the third day. Sheep carcasses were thrown over a designated cliff and buried under rocks. On September 26th, 1942, another 30 pound bomb was dropped, exploding in soft peat. This did not contaminate the animals, but contaminated the soil.
The Contamination Caused by Anthrax Anthrax is a bacteria which lives as spores in the soil. Spores are very robust. The life expectancy of the bacteria is unknown. These spores are not the cause of death for humans. The cause are the particles who enter the lung’s or the gastrointestinal system and germinate here.
Decontamination In year 1943, very little was known about anthrax or how to remove it. Scientists suggested that the solution would be to burn of all the surface vegetation. This method failed. No attempt of decontamination was made till 1978, only existing soil was tested positive for anthrax.
Decontamination Between the years 1978 and 1986 different approaches were suggested: Topsoil of the island being stripped and thrown to the Atlantic ocean. Covering the island with cement The neutralization of anthrax spores by steam, chemicals or radiation The usage of island for nuclear waste
Decontamination Options Using concentrated doses of disinfectants like formaldehyde or bleach. These are toxic to people and environment. Quite expensive as well
Bacteriophage Methods This is done by infecting the bacteria which is already present, so that it repreduces. This will help to get the host bacterias walls to be broken and therefore the bacterium will explode. This study was done in Porton Down Defence Science Labrotoary. The soil was infected by bacteriophage virus, helping the reduce the overall number of bacteria in soil.
Formaldehyde, H 2 CO Used for inactivating proteins, killing most of the bacteria. The solution of H 2 CO in water has the same characteristics as a disinfectant. Formalin is a stronger solution which contains: 38-50% formaldehyde and 6-15% alcohol stabilizers.
The Final Solution In 1986, constant sampling of soil showed that contaminated area was 3.7 hectares. 5% solution of formaldehyde was put on the soil using irrigation channels. This solution helped to disinfect and kill all of the bacteria. 50 lt of solution was used per meter of soil. Another solution formalin which is 38% formaldehyde was injected on the explosion point at the soil. In total 280 tonnes of Formaldehyde and 200 tonnes of seawater were used.
The Final Solution Soil samples were taken again, discovering that dangerous amounts of anthrax spores still existed. The treatment of formalin was re-done for these areas resulting in complete success. Anthrax levels were in safe limits towards the end of 1987.
What Would Change Today? The solution for Gruinard Island was done in 1987. If the same event would happen today, new developments in Anthrax Decontamination such as Bacteriophage can be used. This will reduce the environmental impacts and also costs.