Used oil is only a problem if mismanaged. Because it is insoluble, persistent and may contain toxic chemicals and heavy metals, used oil that is spilled on the ground, poured down storm drains or disposed of with trash, can pollute surface water or groundwater. Oil spilled or dumped on land reduces soil productivity and may contaminate well water. Used oil can foul sewage treatment processes. Oil films on surface water block sunlight, impair photosynthesis and prevent the replenishment of dissolved oxygen, which can lead to fish kills.
Used oil is a regulated waste in Connecticut.
However, it may be classified hazardous if mixed with a hazardous waste such as a chlorinated solvent. Contract with a permitted waste oil transporter to haul oil to a permitted recycling or disposal facility. Heaters must meet design specifications including, have a maximum design capacity of not more than 0.5 million BTU's per hour and vent the combustion gases outside the building. Used oil can be re-refined into lubricating oil, treated and used as feedstock in the manufacture of other products or reprocessed as fuel oil. As there is no substitute for motor oil in internal combustion engines, pollution prevention strategies for used oil focus on proper handling to minimize environmental risks.