Examination of Witnesses (Questions 12020
- 12039)
12020. We turn on to page 17.[17]
I think there is the score for route window C1, is it?
(Mr Denington) Yes, it is.
12021. We know that if it goes over 200,000
it goes to high risk. What was the score they worked out for route
window C1?
(Mr Denington) This score is to be very high
indeed. It is 926,064, so far in excess of the 200,000 which is
the threshold for high risk.
12022. This is a potential cause for dust risk
and nuisance arising from dust risk. Can we get a feel for how
that score compares with other sites? If we go on to page 18 one
can read the diagram, there is a comparison.[18]
I think you have got a helpful note, because it is rather difficult
to see what the sites are, which indicates that the second R from
the left shows the impact on the Royal Oak Portal and that is
route window C1, I think.
(Mr Denington) That is correct.
It shows potentially all the sites likely to be affected and,
as you will see, the left-hand of the diagram, the second bar,
the left is route window C1 which we are very concerned about.
12023. On Crossrail's own assessment, it is
the second highest risk still?
(Mr Denington) That is correct.
12024. Then we turn on to W1 on page 19.[19]
What was the score for W1?
(Mr Denington) The score for W1
is 20,783. This puts it at a level which is twice the threshold
for medium risk, the medium risk threshold being 10,000.
12025. You produced it with W1, you have not
produced the score for W2?
(Mr Denington) No, we have not.
12026. Are you less concerned about W2 than
about W1?
(Mr Denington) Relatively, yes, we are less
concerned.
12027. The following pages are extracts from
the Environmental Statement, volume 6(a). You produced extracts
which show the measures that Crossrail propose to take in relation
to the three tiers offsite, is that right?
(Mr Denington) That is correct. In fact, we
would regard these as fairly typical measures, but certainly represent
good practice in trying to minimise the impact of dust.
12028. Just so the Committee have a full understanding
of this, page 20, 4.2.2 begins: "The standard dust controlled
procedures, Tier 1, will include, as appropriate, site controls
to:—" and there is a list.[20]
If a site is in a particular tier, does it necessarily benefit
from all these measures?
(Mr Denington) No, we understand
that they will be applied at the discretion of the nominated undertaker
as the undertaker saw fit, given the conditions that they were
presented with.
12029. Is there any guarantee that all these
measures will be taken?
(Mr Denington) We do not think there is any
guarantee that these measures will be deployed.
12030. Turning around, we can see Tier 1 and
then a long list under Tier 1. If you go to page 24, on 4.2.4,
those are the two procedures, the same words used, "—will
include, as appropriate, site controls to—:" and then
a list.[21]
That is in addition to Tier 1, is it not?
(Mr Denington) That is correct.
12031. Then on page 26, we get onto Tier 3.[22]
On Tier 3, which is a high risk site, what are the additional
measures that are to be taken or considered?
(Mr Denington) These are chiefly
to deploy all the techniques that have been set out in Tiers 1
and 2, but also additional measures, which I do not think are
stipulated, were giving an example that these might include having
on site personnel monitoring and managing the dust emissions or
other techniques, such as total enclosure of certain operations
to protect vulnerable receptors.
12032. In 4.2.5, does Crossrail contemplate
some form of monitoring?
(Mr Denington) We would have imagined that
would be almost essential, that they would have to have as a minimum
some kind of handheld monitoring device.
12033. Just so we can put this in perspective
and that is the risk approach, can I ask you to go back in your
exhibits to page 18, please.[23]
You produced page 18 which is, in my copy, very difficult to read,
the sites are listed at the bottom, but one site has a higher
dust risk score. Can you help us as to what that is? You may not
be able to read it.
(Mr Denington) I am not quite
sure how to answer the question. Is this the high risk site?
12034. Yes, the one site which gets a higher
risk score than C1, is that Pedley Street?
(Mr Denington) Yes, I believe it is.
12035. The Committee will have heard about the
changes to the scheme in that area of Mile End and Whitechapel.
Whether that Pedley Street score stills holds good following the
changes or not, what we do know is route window C1 is at the higher
end of the risk scores. Have I understood that correctly?
(Mr Denington) That is correct.
12036. Sorry to interrupt you there. Can we
go back to page 27, please, and this is where you highlight your
council's concerns.[24]
Can I ask you to tell the Committee what your concerns are?
(Mr Denington) We have a two-fold
concern. The council is concerned that dust from the proposed
works may exacerbate adverse health effects, for example asthma,
or become a dust nuisance to nearby sensitive receptors. Furthermore,
we are also concerned that the Promoter does not propose to monitor
dust levels prior to the commencement of any works. We are contending
that a baseline study should be undertaken, otherwise it will
be more difficult to assess the significance of dust levels arising
during the work and then subsequently to manage them. We accept
that Crossrail have drawn up a comprehensive set of dust control
procedures, which have just been displayed, and those are to be
applied according to the risk of dust generation, but the dust
monitoring during the construction phase is missing, in our view.
We request that this should be carried out in route window C1
and W1 during the construction phase where the risk of dust nuisance
has been classified as "high" or "medium"
respectively.
12037. I would like to ask you a question about
point 1 on page 27, the extent of your concerns. What is it that
gives rise to the concern that those works may exacerbate adverse
health effects or become a dust nuisance?
(Mr Denington) Dust is something of a catch-all
term, and we are aware that it can have a number of different
components. It will certainly have very fine particles as well
as the courser kind of materials, the very course material being
bricks. As far as the finer particles, these are the ones which
we found to have adverse health effects, not only for those suffering
from asthma but on anyone who suffers from any kind of respiratory
condition. There is a dual concern about the effects of dust.
12038. Turning on to page 28, can I ask you
to outline the adverse consequence which you consider may happen
if this monitoring does not take place?[25]
(Mr Denington) We believe that
without monitoring it will be very difficult to evaluate the effects
that construction works will have on air quality. Baseline monitoring
provides an objective means of establishing conditions prior to
the works starting, and on site monitoring during the construction
phase will give on objective means of determining whether the
works are having an impact. This should give the contractor clear
criteria to work to and enables the local authority to work proactively
so that the dust levels should not give residents reason to complain.
The data will also be used to alert both the contractor and the
local authority to when levels require impacts to be mitigated
further and help keep residents informed about the steps that
are to be taken to mitigate the impacts of dust.
12039. I am going to ask you in a moment about
what the practical benefits of this monitoring will be. Before
doing so, you produced some correspondence. I am not going to
ask you to read it all out. The essential question is has Kensington
and Chelsea asked Crossrail to undertake to do this monitoring?
(Mr Denington) Yes, I believe the correspondence
shows that on a number of occasions we have put the possibility
of monitoring to Crossrail and they have consistently declined
to carry out any monitoring at all.
17 Committee Ref: A132, Impacts on air quality and
proposed dust mitigation measures-Extract from technical reports
(KENSRB-31405-018). Back
18
Committee Ref: A132, Impacts on air quality and proposed dust
mitigation measures-Significance of works at C1 (KENSRB-31405-019). Back
19
Committee Ref: A132, Impacts on air quality and proposed dust
mitigation measures-Extracts from technical reports W1 (KENSRB-31405-020). Back
20
Committee Ref: A132, Impacts on air quality and proposed dust
mitigation measures-Dust mitigation measures Tier 1 measures (low
risk sites) (KENSRB-31405-021). Back
21
Committee Ref: A132, Impacts on air quality and proposed dust
mitigation measures-Dust mitigation measures Tier 2 measures (medium
or high risk sites) (KENSRB-31405-025). Back
22
Committee Ref: A132, Impacts on air quality and proposed dust
mitigation measures-Dust mitigation measures Tier 3 measures (high
risk sites) (KENSRB-31405-027). Back
23
Committee Ref: A132, Impacts on air quality and proposed dust
mitigation measures-Significance of works at C1 (KENSRB-31405-019). Back
24
Committee Ref: A132, Royal Borough of Kensington & Chelsea's
concerns (KENSRB-31405-028). Back
25
Committee Ref: A132, Royal Borough of Kensington & Chelsea's
concerns (KENSRB-31405-029). Back
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