Noise Level Assessment in Geothermal Projects - a Case Study of Menengai Geothermal Project

Abstract

Noise emission is a challenging environmental issue in the implementation of development projects as it constitutes an environmental impact if the area is inhabited by humans or wildlife. In Menengai geothermal project potential noise emission sources include generators supplying power to the rig, discharging wells, electric motors, air compressors, mobile machinery, mud pumps, drilling operation, all of which operate on a 24 hour basis. This study scientifically will assess noise emission and potential pollution through analysis of parameters such as day and night levels (Ldn).The analysis considers two temporal ranges, namely day time (6AM-9PM - 15hours)and night time (9PM-6AM - 9 hours) in the year 2013 at 9 monitoring sites namely Pump House, Lay down Area, Camp Site, Menengai Well 12 and Menengai Well 13. The residential areas monitored were AIC Tulimoi Primary, Marigo community, Rigogo community and Kipng’ococh. Results from noise emission in the residential areas which were monitored at night time indicate that they were within the recommended standards of WHO and occupational exposure limits and community noise of 85 and 50 dB(A) respectively. The levels also complied with the maximum allowable limits of World Bank of 55dB (A) for residential areas. Noise emission levels at Laydown area, Pump house and Campsite which have several operations were all within the recommended World Bank for industrial installations and WHO threshold limit value of 70 and 85 dB(A) respectively.