 Complete the following phrase:  On July 2, 2008, the NHRA shortened Top Fuel and Funny Car races to in response to the ongoing investigation, and extra safety measures were placed at all tracks, including padded retaining walls at the end of sand traps, replacing the polymer nets held up by concrete posts. Although unpopular with the fans, the 1,000-foot distance is still in use for the Top Fuel and Funny Car categories. The FIA shortened the Mantorp Park, Alastaro Circuit, and Tierp Arena rounds of the European Drag Racing Championship because of track concerns, but drag races at Hockenheimring and Santa Pod remained at the distance because of its length until the end of the 2011 season. The 2012 FIA drag racing championships for Top Fuel will only be held at the 1,000-foot distance although the Hockenheimring dragster round was cancelled following track treatment controversy as a result of Formula One officials scraping the entire drag strip in an effort to prevent drivers from using the drag strip launch pad for additional grip in the Südkurve during the 