Accidents will happen, and when cleaning oil spills the right solution depends very much on the size of the spill and its location. Spill Control Centre guides you through the types of product available and where they can, and can’t, be used.
Anyone watching motorsport on television will be familiar with the sight of marshals in brightly-coloured suits dashing onto the circuit with sand or cement to cover oil spilled from cars or motorbikes.
What they’re doing is making the circuit safe by covering the spilled oil to keep it off tyres, and therefore preventing skids, crashes and injury. Crucially, they’re not actually cleaning oil spills on concrete or Tarmac; they’re just making them safer.
It’s a niche spill control method, developed for fast action, but because it doesn’t involve a cleanup after a spill, could be said to have done only half the job.
Doing the whole job requires consideration of how the oil can be picked up and disposed of so it’s kept from harming the environment. What’s more, although the application of cement is good on racing circuits, there are other places where it would be entirely inappropriate.
Oil spill products described
Although there are many effective oil spill cleanup products on the market, they fall into these categories:
1. Mechanical: Useful for large volumes of oil, allowing significant recovery. Containment booms or bunds prevent oil spread, and they can be deployed as a barrier to protect unpolluted areas. Think of the way drain covers work.
2. Sorbents: These can be oil absorbents or oil adsorbents – note the subtle difference in spelling. Both draw off oil using mechanical or chemical means, and allow the oil to be taken away. Some will allow recovery of the oil from them. Absorbents change the physical or chemical properties of the spill they’re cleaning; adsorbents don’t.
3. Bioremediation: These are spores of micro-organisms in a liquid or powder, and ‘digest’ oil spills to leave water and carbon dioxide. Sounds like a miracle cure? Beware; oil contains other additives which won’t be digested, but will be left behind as pollutants. Also, effectiveness of the organisms is governed by acidity, temperature, oxygen levels and the kind of oil spilled.
4. Dispersants: For use when oil is on water. They break it into droplets which disperse further through the water, allowing natural breakdown to happen faster.
5. Surface cleaners: Cleaners break down the oil to make it easier to lift away, and are applied as a powder or liquid. The resulting mixture of cleaner and oil is still a pollutant, so mustn’t be washed down a drain.
6. Miscellaneous: This category covers thinks like sinking agents (which move pollution from the surface of a body of water to the bottom, where it remains a pollutant) and polymerisation products, which transform oil into a rubbery compound – but have potentially detrimental effects on surface or groundwater.
Oil spill cleanup methods and situations
Prevention is always better than cure, which is why we offer a range of measures to prevent spills happening in the first place, like these oil drum storage solutions.
Sadly, spills will happen, for whatever reason so it’s a well to be prepared, by having spill kits appropriate to your particular hazard always to hand. The following five points show what can – and can’t – be used where.
1. Sea, estuaries and tidal waters: Go for mechanical recovery, dispersants, sorbents and bioremediation. Containment booms should be used, where possible, to hold the pollution in one place Products must have approval from the Marine Management Organisation.
2. Beaches and rocky shores: Sorbents and mechanical removal are appropriate here, but be careful to pick those with Marine Management Organisation approval. In the case of protected habitats, you’ll need to consult Natural England (in England, naturally) of Commission Wales certainly before using anything, and also about the nature of what’s being protected.
3. Inland waterways: Mechanical recovery and sorbents can be used, but disposal of the sorbents must be done in line with your Duty of Care and the Hazardous Waste Regulations. Bioremediation may be an option, but it’s one you’d have to talk through with the Environment Officer, who would advise on possible effects on the environment. You may not use dispersants, and the use of surface cleaners is unlikely to be acceptable.
4. Impermeable surfaces like yards, forecourts or roads: Use sorbents and then sweep away the residue. Surface cleaners can be used, but you must be certain that any effluent will be washed into a foul water sewer. Bioremediation can be used, but only if it is subsequently swept up and not washed into drains. Dispersants are no good in this situation. There is nowhere for the oil to be dispersed to.
5. Bare ground: Free oil on the surface can be removed with sorbents, after which you’ll need to removed the contaminated soil. Neither surface cleaners nor dispersants have any value in this situation.
Disposal of oil spill products
This is a complex area, and the Environment Agency has produced a detailed advice document to help. It includes guidance not only about emergency spills but also ‘workday’ spills like ships’ bilges, harbour walls and motor vehicles, and we have included it in our advice centre, where much more information is to be found.