What the peak levels of odours monitored at the Dalmuir waste water treatment works have been in each of the last 12 months.

I have asked Dr Jon Hargreaves, Chief Executive of Scottish Water to respond. His response is as follows: Hydrogen sulphide levels are monitored at the emission stack of the odour treatment plant. The plant started its commissioning process last year but experienced faults in the instrumentation and control systems. These have been addressed, and over the last six months the plant has been operating more reliably. Monthly peak levels of hydrogen sulphide were 90ppb, measured on a 15 minute sampling cycle, with monthly averages from 4ppb to 22ppb. Intensive monitoring of boundary odours will be carried out during the contractual six month odour investigations.