Update on the Disposal of Hazardous Waste from Highway Works






By: P. Croft

Directorate: Development & Environment


Item 6.2, Strategic Planning and Economic Development Policy and Scrutiny Panel, 20th September 2010







Over the last few years the classification of waste arising from road planing has been categorised as hazardous where the presence of tar has been identified. All producers of waste are required to identify the type and nature of the waste produced and we are bound to test arisings from our work for the presence of contaminants. Clearly most roads constructed more than 25 30 years ago do contain tar based material, this includes most roads in North Somerset and across the country.


The disposal of hazardous waste is difficult and expensive and proving to be a burden on the budgets for highway maintenance.


Current Situation


Nationally the issue with contaminated road planings is being discussed jointly with Environment Agency, the Road Construction industry and Local Government to find an acceptable proposal within the existing guidelines. Tests are being carried out on reprocessing the planings and reusing them in roads.


With this information Engineers from North Somerset have engaged in dialogue with the local Environment Agency office with regard to our waste handling. We are required to test for the presence of tar and the associated poly-aromatic hydrocarbons (PAH) and this is done for each resurfacing scheme we undertake.


The following advice has been received from the Environment Agency and describes an interim solution pending the result of the national review.


The conclusion was that there was no issue reusing the bitumen road planings as long as they were treated in line with the aggregate protocol to produce aggregate to the highways standard and are therefore not a waste when they are re used.  But bear in mind that the processing of the road planings would need a permit/exemption depending on the scale. What I wasn't clear about was whether if they took the planings straight to the batching process would they need a waste permit as well as a local authority authorisation. The permitting aspects are being reviewed nationally so we will get an answer eventually.


For coal tar planings the QP doesn't and shouldn't apply as they are hazardous.  Under no circumstances should they go through a hot process as that will allow the uncontrolled release of the PAHs etc.  The Agency/industry are reviewing whether coating the planings would immobilise the contaminants and allow their reuse.  This would have to be a cold coating process.  They are looking at coating them with cold bitumen foam mix although some have suggested concrete.  If they can prove that there is no harm to the environment (via leaching tests) when these are put back into the road then we may deem them not to be waste and as such can be reused in the road without a permit.  Apparently some areas have required each bit of road to have an exemption while other areas have simply turned a blind eye.


So how does that help North Somerset.  Whilst we are waiting a national answer we should look at each proposal on a case by case basis.  Provided that the following points are applied to the coal tar planings we could take a risk based decision and agree a local enforcement position until the national people put something in writing: Tar bound road planings -


The Claire protocol can't be applied because we don't know the risk of the reuse at this stage and anyway it would be easier to use the aggregate protocol.




Engineers will maintain a watching brief on the national situation and ensure the procedures within North Somerset are within the current guidelines and directions.


Temporary storage capacity is limited and additional area for storage need to be identified, a private site has been found at Avonmouth but there is a cost involved in the use of this which officers are trying to reduce. If this is a viable and cost effective option approval will be sought when a detailed proposal if developed. In the short term some planings will need to be sent for disposal and the costs incurred until the national resolution is identified. Engineers will continue to design out the need for tar removal from all resurfacing schemes but this cannot be eliminated altogether.


A further report will be presented when there is any change in the guidelines and advice.