Page 21 - Swale AQMA Feasibility Study April 2020_
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AQMA Feasibility Assessment
               A2 – Keycol Hill and Key Street, Swale




                              R14         Keycol Hill         13.1

                              R15         Key Street          12.9

                              R16         Key Street          12.9


                              R17         Key Street          13.4


                              R18         Key Street          12.7

                              R19         Key Street          13.4

                              R20         Key Street          13.1


                              R21        London Road          11.1


                              R22        London Road          12.3

                              R23        London Road          12.5

                        Note: Bold denotes exceedance of the annual mean AQS. Underline denotes indicative
                        exceedance of the 24 hour AQS.
                 4.9    The  data  in  Table  4.3  show  that  annual  mean  concentrations  of  PM2.5  are
                        consistently  below  the  25μg.m   target  value  in  all  modelled  scenarios.  The
                                                         -3
                        highest modelled concentration of 16.1μg.m  was at Receptor R8, 35.6% below
                                                                      -3
                        the target value.


                        Summary of results


                 4.10   The  air  quality  modelling  results  based  on  the  2018  ratified  data,  show  that
                        there are likely exceedances of the long term and short-term AQSs for nitrogen
                        dioxide (NO2) on Keycol Hill, but not Key Street.

                 4.11   Figure 2 and Figure 3 identify the predicted annual average NO2 concentrations
                        in the year in 2018.  These data show likely exceedances on Keycol Hill only and
                        therefore an AQMA could potentially encompass these locations, as suggested
                        in Figure 4.

                 4.12   There were no PM10 AQS exceedances within the model domain and modelling
                        results for PM2.5 also showed annual mean concentrations are likely to be well
                        below the AQS target value.















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