Originally Posted by
RacerT
Noise is an interesting issue. We chose the Hampton Downs site after looking at a lot of other areas, such as Helensville, Kaukaupakaupa and the Meremere coal mine quary. Noise was one of the major concerns at every proposed site and it quickly became apparent that the 10 acre block 'Paradise Seekers' were never going to be happy with a nearby circuit - NIMBY's!
The Northern Waikato is sparcely populated and the HD site at the benefit of 1200 acres of Tainui land to the west, 526 acres of Corrections facility to the south, 80 acres of Transit wetland to the north and 530 acres of sheep farm to the east.
Hampton Downs has a noise boundary that extends far from its own boundaries. This is based on the contours of the land surrounding the circuit. All the neighbours within the noise boundary signed of on this noise plan. This took considerable consultation, with many cups of tea and chocolate biscuits! The key to the noise plan is that it is based on the MSNZ 95 decibal rule, 30 metres from the track edge. To add to this, Hampton Downs has a range of days that it can run with varying noise levels. Our noise plan also has quite a degree of contingency in it, so if we have differing weather conditions, we can still comply at the boundary.
Even the 30 metres from the track edge is not definitive enough. I would think that a distance from the middle of the track would be more accurate, because if you take a 12 metre wide track, the cars position on the track can alter the distance to the noise meter by up to 20%.
It doesn't seem to be an exact science! When I was at a Goodwood club meeting in 2001, they were measuring in a static manner with a noise meter behind the exhaust pipe. This obviously takes no account of induction or aerodynamic noise.
A good noise plan with the neighbours buy in is imperative for any circuit to survive. We have many neighbours around Hampton Downs that were consulted and most of these people are supplied with Gold Cards for free access to events as part of our long term strategy.