Page 18 - Swale AQMA Feasibility Study April 2020_

AQMA Feasibility Assessment
A2 – Keycol Hill and Key Street, Swale

R13 Keycol Hill 49.5

R14 Keycol Hill 44.1

R15 Key Street 33.9

R16 Key Street 27.9

R17 Key Street 31.2

R18 Key Street 24.9

R19 Key Street 30.9

R20 Key Street 27.6

R21 London Road 36.1

R22 London Road 31.3

R23 London Road 29.8

Note: Bold denotes exceedance of the annual mean AQS. Underline denotes indicative
exceedance of the 24 hour AQS.
4.3 The data in Table 4.1 show that annual mean concentrations of NO2 are
predicted to exceed the AQS at four modelled receptors on Keycol Hill, and
none on Key Street. The highest concentration was 78.6μg.m , 96.5% above
-3
the AQS. This receptor (R8) is located adjacent to the newly included diffusion
tube SW124 (31/33 Keycol Hill).

-3
4.4 For the hourly AQS for NO2 (200µg.m not to be exceeded more than 18 times
-3
a year), LAQM.TG(16) states that if the annual mean is below 60µg.m , this AQS
should be met. The data in Table 4.1 show that modelled annual mean NO2
concentrations exceed this threshold at receptor R8.

4.5 All concentrations modelled to be above the AQS in 2018 were situated on
Keycol Hill. As such, there is scope for considering implementing an Air Quality
Management Area along this road, for both the short-term and long-term
exceedances of the AQS for NO2. A potential AQMA boundary based on the
2018 modelling results has been indicated in Figure 4.

Particulate Matter (PM10)

4.6 Modelled results for PM10 in (2018) are presented in Table 4.2.

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