- Conclusions
- The data show a strong influence of benzene emissions during refilling of vehicles on levels at both the petrol pumps and at the forecourt perimeter. On average road traffic emissions were estimated to contribute approximately 44% to benzene levels measured at the front of the forecourt perimeter adjacent to the road.
- The exceedances of the AQS which were estimated to occur at the petrol pumps are of only small concern with respect to public health as exposure will only occur over a very short time period during refuelling.
- Exceedances of the AQS which were estimated to occur at forecourt perimeter sites are of greater concern, as two of these sites were situated directly adjacent to residential housing where longer term exposure of the public is likely. Such results may suggest that exceedances of the AQS are likely at other locations where petrol stations are located directly next to residential housing.
- The results show that Stage I controls are effective at reducing benzene concentrations at the forecourt perimeter by up to 60%. However, Stage I controls do not ensure compliance with the AQS, as at some stations fitted with Stage I levels remained above the AQS. The results from the one station used in this study which was fitted with Stage II controls suggest that Stage I in combination with Stage II controls may be necessary to guarantee compliance with the AQS as Stage II controls provide significant additional abatement.
- Benzene levels recorded at all the roadside sites were estimated to be below the AQS.
Report prepared by Stanger Science and Environment
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