AWS who carried out the noise monitoring decided to change the planning condition from measuring LAeq to LA 90 - now I will get too technical but this means they have decide to try and hide the level of noise to suit their needs using a noise description of L90 rather than LAeq as set out in the planning condition
Dear Planning enforcement
Dear Planning enforcement
We wish to lodge a Section 160 potential breach of planning against the Grouselodge Wind farm planning application number 08/58.
We live at XXXX, Ardagh, Co.Limerick and having studied the EIS (environmental impact statement) submitted by the developer along with the planning conditions set by ABP we believe that this wind farm is failing to operate within its compliance limits and as such given the wording of the ABP Order should be "stopped until written agreement is reached with the planning authority on design or operational alterations intended to reside the noise accordingly. "
We have read the AWS noise compliance report and note that they have change the planning conditions as set down by ABP to suit their needs. This is a violation of the PDA (2000) as amended. Rather than using the noise description “LAeq (5min)” as set out in the planning condition they have used “LA90 (10 min)” and then added 2db to compensate for the fact they are using LA90. This is completely unacceptable because the L90 relies upon using only 10% of the quietest time in the 10 minute period for noise measurement whereas the LAeq uses noise data from the entire period.
This use of LA90 masks the variation of the noise generated by the wind farm. For example it would remove any amplitude modulation which is typical with these wind turbines where it can be observed that a 10db variation in the noise levels over a 1 second interval can occur. (i.e at blade pass frequency). Below is a measurement from a Nordex turbine displaying these phenomena.
We also note that no measurement of tonality was taken. The Nordex turbines are well known for creating a drone around the 168Hz Frequency range. Here is a noise recording taking from a Nordex turbine showing the very high tonal component. This is indicated by the massive ridge in the 168Hz range.
We ask that
a) with immediate effect you issue an order to stop these turbines until such time as they can produce a noise compliance report which is measured to the requirements of the ABP planning condition.
b) You ask for a noise report which includes
a. The use of the correct noise description of LAeq (5min) as specified in the ABP Order.
b. When plotting the noise data that only the down wind noise measurements are used as using any others will lead to erroneous data plots
c. A set of tonal measurements to the Institute of Acoustics approved methodology to ensure that there is no penalty to apply for tonal components.
I look forward to your immediate action on this.
Yours
XXXX
XXXX
Ardagh
Co. Limerick
