| Topic: | Brentford Great West Quarter - Where does the air come from? | |
| Posted by: | Tim Henderson | |
| Date/Time: | 05/12/14 15:03:00 |
| The Highways Agency recently announced that it was investigating proposals to make M4 Junctions 3 to 12 into a "smart motorway" by using the hard shoulder. I asked for the Preliminary Environmental Report that covers the scheme and browsing through it I came across the paragraph : "Local operational effects (Opening Year, 2022) 6.14.22 The magnitude of change in NO2 concentrations at sensitive receptors at junctions 3 to 1 of the M4 is predicted to be small at one receptor (X617) which is predicted to be above the annual mean objective value with the Scheme in place. However, this location is unlikely to have Openable windows, as an apartment block and may therefore already be mitigated against poor air quality. This increase is due to the proximity of this receptor to the A4 and M4 at junction 2 and an anticipated increase of approximately 4,900 vehicles on the M4. The predictions at X617 have been considered as part of the overall evaluation of significance for operational air quality. However, further work will be undertaken to consider how this location is assessed and whether this location is included in the evaluation of significance for the final ES. The magnitude of change in NO2 concentrations at all other receptors is predicted to be imperceptible resulting in a negligible change in air quality. 203 receptors are predicted to be above (160) or just below (43) the annual mean objective value with the Scheme in place. It is also anticipated that exceedances of the 1-hour mean objective are unlikely in this part of the study area as annual mean concentrations at all receptors are less than 60 μg/m3." The maps showed that X617 was a single point ("receptor") representing the whole of the Great West Quarter while on the other side of the road each terraced house was an individual receptor! Do windows open in the Great West Quarter ? If not, where does the air come from ? |