From the OXFORD MAIL   A new report shows that Horsefair  in Chipping Norton has the highest levels of nitrogen dioxide in West Oxfordshire. Horsefair along with Bridge Street and Mill Street, in Witney  remain above the Government target levels.  The figures are in a report to the June 12th  meeting of West Oxfordshire District Council's environment scrutiny committee.  Last year all three sites were above the pollution target level of 21 parts per billion (ppb), and remained so this year. The measurement at Horsefair was 35ppb, with Mill Street 33ppb, and Bridge Street 29ppb. Thirty-two sites have been monitored. The only other places above the target level were in Burford High Street (23ppb), and West Street  in Chipping Norton (24ppb). Selected sites in Charlbury, Carterton and Eynsham remained well below the level, while others at Woodstock and Bladon were just below. Martin Rowland, head of the environmental health department, said the council would have to declare the sites Air Quality Management Areas if it did not think the target level would be met. He said: "As the prime source of nitrogen dioxide affecting residents is traffic, the action plan would have to involve traffic management."     (READ THE REPORT)   Chipping Norton Town Council has joined calls for measures to control heavy lorries using the A44.