Lakeside toxic cloud was no isolated incident
The toxic cloud released over Colnbrook on 5 September was not a blip but the third time this year that PM10 levels reached astronomical levels, analysis has shown.
Levels of PM10 recorded were 989 µg/m3, 20 times where they should have been. The figures were deleted from two monitoring sites 6 days after we broke the news, without explanation.
But analysis of the remaining data from all monitoring stations going back to the launch of the Grundon super-incinerator in January 2010 shows the incident was not an isolated occurrence. And the worst three breaches – by far – have all occurred THIS year.
While the figures for the 5th September were 20 times target levels, in May and january this year they reached over 30 and 40 times respectively.
And there have been regular occurrences since the incinerator opened, frequently coinciding with peaks seen in other pollutants at the same time. The top six PM10 levels seen since the plant was opened are highlighted in the chart below.
Nitrogen Dioxide (NO2), the only other pollutant for which target levels have been set, has also seen “blips” where recorded levels have been an order of magnitude above where they should be. The four worst are shown in the chart above.
The Air Quality Objective is set at 40 µg/m3 for both pollutants as a yearly average but an “exceedence” is only counted if levels over 50 µg/m3 PM10 are recorded for over 35 days or for 18 continuous hours of NO2 breach at 200 µg/m3 levels.
So Grundon is allowed to emit frightening levels of PM10 or N02 so long as they do not do it for very long.
And, as we revealed following the deletion of the data for the spike on the 5th, as much as 5% of the data is missing so far in 2013. In previous years up to 25% has been missing, making the statistics of dubious value.
The highly erratic figures suggest little consistency and bring into question the use of mean readings without prescribed upper limits.
While there has been no comment yet regarding why the data was deleted for the Slough Lakeside 2 monitoring station at Grundon’s Energy from Waste facility, 4 other monitoring stations further away also recorded levels of particulates way in excess of normal levels – suggesting that an isolated sensor malfunction cannot be blamed.
Similar interrelated sets of readings were seen during the other peaks this year.
Grundon failed last month to convince the Scottish Parliament to approve a second incinerator. Planners were not convinced that the company has effective noise and pollution controls in place.
Until Grundon explains itself, the experience in Colnbrook will no doubt frame any future attempts by the company to persuade residents in other parts of the country otherwise.
Grundon has so far ignored requests to comment.