Noise monitoring and population surveys were conducted by a subconsultant, MateriaLab Ltd under the guidance of ERM within the period from December 1998 to February 1999. The subconsultant's Monitoring Data Compilation is presented in Appendix B(1) where the monitoring locations, methodology, monitoring results and estimated population exposure pattern are included in detail.

The monitoring schedule is attached in Table 4.1 in Appendix B. The monitoring was conducted with the following considerations:

noise measurements were taken twice for the same monitoring station under the same monitoring session on different days to acquire more data for statistical purpose;

• noise monitoring was conducted in daytime (0700 to 1900), evening (1900 to 2300) and night-time (2300 to 0700) hours for the following activities:
• Cargo Handling Areas and Midstream Operations (except for Kennedy Town Praya where the daytime monitoring was omitted because of the heavy traffic noise interference)
• Industrial Estates
• Existing Industrial / Residential Interfaces
• Container Terminal
• noise monitoring for Open Storage Area and Container Trucks Parking and Repair were undertaken during daytime (0700 to 1900) and evening session (1900 to 2300) hours only to tie in with the operation mode of these activities;
• Leq 30min and L90 measurements at each location were conducted. For evening and night-time monitoring sessions, 3 consecutive Leq 5min were taken instead of Leq 30min on some occasions where constant low noise levels were the prevailing characteristics. L90 measurements were taken to indicate the background noise level other than that attributable to the noise source. However, the focus of this monitoring exercise is the Leq; and
• Population densities of an area within a 300m radius of the monitored activities and sources at each survey location were established (Table 6.2a-f in Appendix B). The number of noise sensitive premises corresponding to each noise level band were estimated and a benchmark of 4 people per residential dwelling is to be applied to arrive at an indicative population figure.

Territory wide baseline studies of the current nature are useful tools in providing policy makers and planners a macro perspective of the noise environment. Exercise of this nature, however, while providing useful bird's eye views may over-generalised the relevant situations. This particular limitation however would not limit the usefulness of the study at the strategic level.