In 2005, regional councils were required to outline urban areas which either were, or were likely to exceed, the national environmental standards (NES) for PM10. These areas were termed airsheds.
In Marlborough, Blenheim is currently the only designated airshed.
Each airshed is required to show compliance with the NES by 2013. In addition, each council is required to establish a straight line path (SLiP) which is used to track progress towards compliance with the NES by 2013. The straight line path is based on the worst recorded air pollution day and assumes a linear decrease in emissions from 2005 to 2013.
See the Ministry for the Environment website for details of the straight line path for Blenheim.
In order to ensure compliance with the NES by 2013, a number of management options are required to be implemented to reduce total emissions to the Blenheim airshed by 25%.
Although currently PM10 is the only criteria air contaminant of concern in Marlborough, further monitoring of other contaminants may be necessary should further information on their concentrations and/or impacts come to light.