Land Contamination: Technical Guidance on Special Sites: Acid Tar ...

White Oil• Acid tar lagoons from white oil production generally follow the distribution of oilrefineries in the UK which have typically been sited at coastal locations;• figures for acid tar production from white oil refineries are often not available as thefigures were generally incorporated into the overall figures for desulphurisation;• estimates suggest that between 8,000 and 12,000 tonnes of acid tar were producedannually per refinery at the height of production in the 1950s at an estimated ten totwelve sites in the UK (annual total of around 100,000 tonnes of acid tar);• over the period 1930 –1980, there could have been as much as 2 million tonnes of acidtar produced in total;• in 1980 there were six refineries producing acid tars but by 1986 there was only one.Box 2.3 Scenario: What quantity of acid tars might be found at a white oilrefinery?If we assume, based on the above, an average of 10,000 tonnes of acid tarsproduced per refinery per year, then a refinery operating over 40 years wouldhave produced some 400,000 tonnes of acid tars.A plant at Lviv in the Ukraine reportedly has 300,000 tonnes of acid tars thatwere disposed of over several decades (International Conference on Analysis &Utilisation of Oily Wastes, AUZO ’96, 1996).The former Sand Springs refinery in Texas, which operated from 1870-1940and was classed as a Superfund site, was found to have 100,000 cubic yards(around 90,000 tonnes) of acid tar out of a total of 135,000 cubic yards ofpetroleum wastes in several earthen pits. Sulphuric acid had been used to treatraw crude oil to polymerise unstable compounds. (Grajczak, PE. Remediationof acid tar sludge at a Superfund site, Texas, 1995.)Re-refining• Information relating to historical re-refining sites in the UK is very limited;• during the Second World War there were an estimated 30-40, mainly small, rerefiningplants set up to supply lubricating oils to the military. As governmentsubsidies were withdrawn and pollution control legislation was tightened, many rerefiningworks closed. By the mid-1980s only one re-refining plant remained inoperation, producing 500 tonnes of acid tar per year;R&D <strong>Technical</strong> Report P5-042/TR/04 11