Page 111 - Updated SuDS Design & Evaluation Guide-Newham V3 Spreads

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Detailed Design 9.7.4 Dealing with spillage ■ ■ spillage is contained at or near the surface 9.7.5 Water quality design checklist Information presented for Detailed Design

SuDS components are very effective at
so that it is visible and accessible.
dealing with ‘day to day’ pollution. When a
Item
What is being checked
spillage occurs this can overload the
assessment
slow travel time through a SuDS
treatment processes which occur within
management train allows time for reaction
Method of
Design statement to specify method of
Sensitivity of receptor and level of
SuDS components. Where the spillage is an
and initial clean up to take place
discharge and sensitivity of receptor.
treatment required
discharge
organic based pollutant a spill kit is used to
■
mechanical mechanisms such as shut off
take up the excess and the residual pollutants
site biodiversity and amenity assets and
left in situ to breakdown naturally.
components and management train.
valves should be avoided due to the
the wider environment.
inherent risk of the essential keys not be Treatment Sufficient treatment in place protecting Layout drawing clearly indicating SuDS
Details of Indices approach and
Designing for spillage should demonstrate:
locatable at the time of spillage. An Evidence of source control, subcatchments infiltration screening assessment (as
awareness of outlet locations which are and management train. appropriate).
visible and can be easily sealed off will Infiltration Presence of SPZ’s, contaminated land, Coordinated constraints plan. Evidence
provide simple and robust containment. depth to seasonal high groundwater table. of discussion with EA where appropriate
Construction Demonstration of how site runoff could be Section of the drainage design
phase managed during construction to minimise statement outlining a potential approach
the risk of pollution to the wider for construction runoff management.
environment due to silty construction Contractors will be responsible for
runoff. uptake.
Milk spillages will bypass conventional drainage methods of spill containment Operation and Operation and maintenance should be Concise operation and maintenance
https://naturalresources.wales/about-us/news-and-events/news/nrw- maintenance simple to understand and easy to plan. Description of tasks and detailing
respond-to-milk-spillage-in-llantrisant/?lang=en. plan implement. Where available, SuDS design of where personnel are required to visit
105 should deploy natural treatment process site to remove hydrocarbon based 106
to breakdown organic pollutants passively. pollutants (i.e. organic pollutants have
Contingency measures in the event of a not been fully broken down passively as
minor / major spillage part of SuDS treatment process).
Plan indicating potential for containment
and positioning of spill kits (as
appropriate)

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