TfL Ref: 2410-2425

Thank you for your request received by Transport for London (TfL) on 28 October 2024 asking for information about the Northern line.

Your request has been considered in accordance with the requirements of the Environmental Information Regulations and our information access policy.  I can confirm that we hold the information you require.  Your questions and our replies are as follows:

Hi, I am particularly concerned about the section of the northern line adjacent to Archer Academy East Finchley ( Secondary school situated along the Northern line)  According to one of your own "summary of known/suspected Hazardous Materials" for the above section of tracks, updated on Oct 2020 - presence of asbestos has been confirmed along the tracks (both debris and Cable sheaths)

The items include debris of asbestos known and potential on the following roads:

N072-N-RD23 - Finchley Central - East Finchley Road 23- R190429 (woven cable sheath + potential debris)
N072-N-RD23 - Finchley Central - East Finchley Road 25- R190430 ((woven cable sheath + potential debris)
N072-N-SBFA -Finchley Central - East finchley road 35 - R190431 - KNOWN => "Removal/debris pick of asbestos throughing was carried out on section. Some still remains and there is always the possibility that asbestos cement troughing debris may be uncovered"

N072-N-NBFA - East Finchley - Finchley central Northbound

Question: Please inform if remediation was properly done to remove all debris or cap them, plus recorded evidence.  There is also several woven cable sheaths along these roads. 

The asbestos debris pick was undertaken by one of our Hazardous Materials Framework Contractors who are licenced by the Health and Safety Executive to undertake asbestos remedial work.  When the work is finished, we receive completion certificates and waste consignment notes as evidence that the work has been completed satisfactorily and the waste has been disposed of correctly.  An example completion certificate for asbestos remedial work in the location of interest to you is attached.

Any asbestos debris was removed back in 2010 and completion paperwork for this is attached as per above. Further debris picks were carried out on various sections of the Northern line in 2023 including the High Barnet branch, where asbestos debris was identified following a scheduled re-inspection in 2022.  However, no further debris was identified in the section between Finchley Central and East Finchley. 

With regard to the fact that our records state that some debris still remains, this is because even though all visible debris was removed, there is always the possibility that more could be buried within the ballast so the surveyor could not state with certainty that all debris had been removed even if none was visible.  We can reassure the public that any asbestos containing materials (ACMs) that may be present in this location would not present a risk of elevated airborne fibre levels.  It has been stated before but it is worth repeating that airborne fibre monitoring is routinely carried out during asbestos remedial work and results are well below HSE applicable limits.  In open sections background airborne fibre levels would be even lower so any ACM’s located on or near the track would not present a risk of exposure to occupants of the Archer Academy or any other location in the vicinity.

Question: since that section of the Northern line is outdoor, can you confirm if these cables are insulated/encapsulated with rubber etc or is the asbestos sheaths exposed? Pls provide pictures as example

Asbestos sheathed cables may be encapsulated but there is no requirement for this so there will be unencapsulated cables present.  The attached photo shows an example of an asbestos sheathed cable.

Ballasts and tracks were completely replaced in 2016, was a remediation put in place for potential debris ( ie textile cap under tracks etc)

Where ballast and track is replaced, a membrane is installed.

Please provide the following surveys:
-demolition survey ref R559180 - Attached
-asbestos survey ref R559176 - Attached
-asbestos survey ref R480481 - Attached 
-asbestos survey ref R190433R – Attached - please note that this is archived information i.e. not current.  

Please note that in accordance with TfL’s obligations under the Data Protection legislation some personal data has been removed, as required by Regulation 13 of the Environmental Information Regulations. This is because disclosure of this personal data would be a breach of the legislation, specifically the first principle of the legislation, which requires all processing of personal data to be fair and lawful. It would not be fair to disclose this personal information when the individuals have no expectation it would be disclosed and TfL has not satisfied one of the conditions of Schedule 2 which would make the processing ‘fair’.

Question: what are the measures put in place by TFL to ensure no pupils attending this school which is along a tube track are not exposed on a daily basis to asbestos while attending school - there is an average of 250 trains per day on this section which could disturb any debris or exposes asbestos.

TfL have a specialist team who are responsible for the management of all ACMs in accordance with the Control of Asbestos Regulations (2012).  This asbestos management includes arranging re-inspection of known ACMs in order to ensure they remain in good condition.  If any such re-inspections identify any ACMs in poor condition, remedial action is taken.  Although asbestos braided cables are present along the track section between Finchley Central and East Finchley, these would be included within the re-inspection programme.  The fact that asbestos braided cables are present does not mean that they will release asbestos fibres.  This is known to be true because extensive investigations have been undertaken on the potential for fibre release from various ACMs, including asbestos braided cables, during disturbance, in order to assess the risk.  The disturbance used in the investigation was to blast air at the ACM to simulate disturbance that may occur during train movements.  The findings were that the risk of fibre release from ACMs of this type was very low, even within the confines of a tube tunnel.  Airborne fibre monitoring is routinely carried out during asbestos remedial work and results are well below HSE applicable limits.  In open sections background airborne fibre levels would be even lower so any ACMs located on or near the track would not present a risk of exposure to occupants of the Archer Acadamy or any other location in the vicinity.

If this is not the information you are looking for, or if you are unable to access it for any reason, please do not hesitate to contact me.

Please see the attached information sheet for details of your right to appeal as well as information on copyright and what to do if you would like to re-use any of the information we have disclosed. 

Yours sincerely

Sara Thomas

FOI Case Management Team

General Counsel

Transport for London