Examination of Witnesses (Questions 7740
- 7759)
7740. That the rails of the new railway will
be ground smooth prior to the opening of the railway—D10,
2.11.
7741. That the gradual deterioration in rail
and wheel condition will be limited to control any consequent
worsening of groundborne noise and vibration—D10 paragraphs
2.10 and 2.11.
7742. That the key input assumption of the combined
condition (or "roughness") of the wheels and rails will
not exceed that which has been, and will continue to be, assumed
in the modelling, by way of imposing a specification on the operator
of the railway—D10, 2.10.
7743. To include recognition that the local
authorities apply different policies to those proposed by the
Promoter—D10, 2.13.
7744. That the nominated undertaker will use
"reasonable endeavours" to adopt mitigation measures
that will further reduce any adverse environmental impacts caused
by Crossrail insofar as these mitigation measures do not add unreasonable
costs to the project or unreasonable delays to the construction
programme—D10, 2.14.
7745. On completion of the track design, where
the nominated undertaker predicts that it would exceed the local
authorities' preferred standard of 35dB LAmax, S at any dwelling,
then the nominated undertaker will provide additional information
to the local authorities explaining its position, and will take
into account the local authorities' comments—D10, 2.13 and
4.2.
7746. The definition of an adverse groundborne
noise impact is specific in the context of this project. According
to the Promoter's assessment criteria an adverse impact will not
occur if the groundborne noise levels are below 35dB LAmax, S.
The Promoter has declared that following the incorporation of
the additional mitigation as instructed by the House of Commons
Select Committee, there are no adverse groundborne noise impacts
expected at residential dwellings across the tunnelled section
of the route.
7747. The contents of the Environmental Minimum
Requirements: General Principles paper, which have been agreed
by the Promoter and the Local Planning Authorities, has assisted
us greatly in achieving agreement to IP D10 Version 3. The relevant
passage from the EMRs General Principles paper can be found at
paragraph 1.5 and requires the nominated undertaker to use reasonable
endeavours to adopt mitigation measures that will further reduce
any adverse environmental impacts caused by Crossrail, insofar
as these mitigation measures do not add unreasonable costs to
the project or unreasonable delays to the construction programme.
7748. Of note is that the commitment in paragraph
1.5 stands "apart" from the controls and obligations
in the EMRs that specifically require that impacts which have
been assessed in the 2005 Environmental Statement will not be
exceeded. In our view the provisions of paragraph 1.5 should be
seen in the context of the most recent predictions undertaken
by the Promoter (i.e. post-Environmental Statement), the results
of which conclude the existence of no adverse impacts. By this
the Petitioners seek to put on public record that with no adverse
impacts currently envisaged by the Promoter the local authorities
are expecting that the application of reasonable endeavours would
ensure that groundborne noise levels inside dwellings fall below
35dB LAmax, S.
7749. This series of commitments and observations
has enabled agreement on the principles of IP D10 Version 3, but
as explained previously not to the maximum permissible limit for
residential dwellings which remains presented in Table 1 of that
document, and which the Promoter does not alter despite no cost
burden apparent to the project in doing so. This is a fundamental
point for local authorities to put on record as it should not
be regarded as any precedent for future railway schemes or other
development where groundborne noise is a concern and where local
authority policies need to remain intact to prevent challenge
to their saved policies on groundborne noise.
7750. I hope that your Lordships can appreciate
the major obstacles around which Camden has had to negotiate in
reaching an agreement on this matter.
7751. CHAIRMAN: Do the Promoters have
anything to say on this?
7752. MR TAYLOR: My Lords, I do have
a statement to make in response.
7753. CHAIRMAN: Have you circulated it?
7754. MR TAYLOR: I have not, I am afraid;
I only have a handwritten note in front of me.
7755. CHAIRMAN: Doubtless you will.
7756. MR TAYLOR: I doubt if anybody else
could read my writing; in fact I suspect I might have trouble
myself.
7757. We had understood that an agreed position
in relation to groundborne noise and vibration had been reached
with the London Borough of Camden and it was not until yesterday
that we found that Camden would be continuing to make points to
you this morning regarding the appropriateness of 35dB LAmax,
S as a design noise criteria, and it is only right that I make
clear the Promoter's position in relation to that issue.
7758. This statement is to make it clear for
the record that the Promoter continues to consider that a design
noise criterion of 40dB LAmax, S affords an appropriate level
of protection to the amenity within residential properties from
noise from underground railways. Nothing in Information Paper
D10 should be taken as indicating that the Promoter has changed
its position in relation to that matter. IPD10 retains 40dB LAmax,
S as the design noise criterion for the protection of residential
properties in the design of the Crossrail project. The Promoter
relies upon the fact that 40dB LAmax, S has been successfully
used in the past as a design noise criterion in relation to a
large number of underground railway schemes, including, for example,
the Jubilee Line Extension. The Promoter is not aware of any complaints
regarding groundborne noise associated with the Jubilee Line Extension
from those occupying residential properties above it. The use,
therefore, of 40dB as a design criterion has in fact protected
the amenity of residential occupiers in that particular case.
7759. The Promoter believes that the use of
a 40dB LAmax, S criterion corresponds to a level of noise that
is lower than the relevant thresholds in the guidelines for community
noise published by the WHO. The Promoter does not believe that
there is any published scientific evidence to suggest that the
adoption of a 35dB LAmax, S criterion would produce any material
improvement to the amenity of residential occupiers compared to
the adoption of a 40dB LAmax, S criterion, and that is a point
that was accepted by Mr Methold, who is the noise expert for the
London Borough of Camden, in cross-examination before the House
of Commons Select Committee, and you can see that in volume 2
of the Special Report at page EV302, paragraph 3061. The adoption
of a design criterion of 35dB LAmax, S would, therefore, potentially
impose additional cost on an underground railway project whilst
not bringing about any material benefit to the living conditions
of those living above it. In short, the Promoter considers that
40dB LAmax, S provides a design noise criterion that works and
a design noise criterion that is cost-effective.
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