Having changed my petrol tank I thought I'd be a good citizen and find out how to make it safe before taking it to the tip. The council's answer was that they will not take petrol tanks, made safe or not, and they wouldn't tell me how to make it safe. So I now have not only an unsightly petrol tank in the front garden, but a highly flammable unsightly petrol tank.
Apart from the traditional method of fitting to a vehicle, parking in a ditch or lay-by, and applying a match, how does one go about making a tank safe, and where do you get rid of them?