London Wider Waste Strategy - London - Greater London Authority

Recommendation 44: It is recommended that the GLA make it clear that the arisings
of ‘hard’ and excavated’ construction and demolition wastes in London may be
considerably different to the figure of 6.05 million tonnes that is often quoted
from the Symonds’ surveys of 2001 and 2002 and subsequently used as the
basis for further analysis. Such analyses should recognise that the Symonds’
survey data should be used as a range (3.70-8.40 million tonnes), with the
associated confidence level, and acknowledge the potential for significant
uncertainty in the modelling results. An appropriate contingency should be
included within any strategy measures based on the data modelling to allow
for a significantly greater, or indeed lesser, quantity.
5.10. In addition, the Symonds surveys exclude the other waste streams from construction
and demolition activity that do not fall under the category of ‘hard’ or ‘excavation’
wastes (refer definition in paragraph 5.5). These could be termed ‘soft’ C&D wastes and
include a wide range of wastes such as timber, plastics, metals, other packaging, plaster
and certain forms of hazardous wastes (excluding soils classified as ‘contaminated’
which are included under ‘excavation’ wastes). Discussions with the Environment
Agency confirmed that these ‘soft’ wastes are also not captured through their surveys
on commercial and industrial waste arisings. Therefore, these ‘soft’ wastes are
essentially a hidden waste stream since they are not included within either survey. This
is because the ‘soft’ construction and demolition wastes fall in-between the data
reported by DEFRA (formerly DETR)/ODPM and the Environment Agency as the former
surveys at the point of receipt for ‘hard’ and ‘excavation’ wastes whilst the latter surveys
at the point of arising (i.e. at commercial and industrial premises).
5.11. There is perhaps some ambiguity at present regarding whether these ‘soft’ wastes
should have been reported as a construction and demolition waste or classified as
industrial or perhaps commercial waste. Nevertheless, in the future, all wastes arising
from construction and demolition sites will need to be classified as ‘construction and
demolition waste’ with respect to the European Waste Catalogue (i.e. code 17 in the
catalogue) since this is a source based description. Therefore, with respect to the
definition in the European Waste Catalogue, it is apparent that the Symonds survey data
is likely to represent an underestimate of total construction and demolition wastes.
Since ‘soft’ C&D waste is excluded from any current surveys and very little composition
data is available on C&D wastes (refer to para. 5.17), it is not possible to predict the size
of this hidden waste stream with any confidence.
Recommendation 45: It should be made clear that ‘soft’ C&D wastes (eg. timber,
plastics, metals, packaging, plaster) are excluded from the Symonds’ survey
data estimates, and future planning / modelling should take steps to (a) allow
for this in any future waste modelling analyses, e.g. to inform the development
of the London Plan, and (b) obtain data on the size and composition of this
waste stream.
5.12. At present, a further Symonds study is underway, with publication anticipated in
September 2004 (funded by the Office of the Deputy Prime Minister). As part of this
study we contacted the authors, but unfortunately the current study is not sufficiently
advanced for them to be able to make any data available to us.
Strategic Waste Management Assessment: London
5.13. With regard to construction and demolition waste, the SWMA for London (SWMAL)
uses the data from Symonds as discussed above.
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